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1 | // SPDX-License-Identifier: GPL-2.0+ |
2 | /* | |
3 | * Maple Tree implementation | |
4 | * Copyright (c) 2018-2022 Oracle Corporation | |
5 | * Authors: Liam R. Howlett <Liam.Howlett@oracle.com> | |
6 | * Matthew Wilcox <willy@infradead.org> | |
fd32e4e9 PZ |
7 | * Copyright (c) 2023 ByteDance |
8 | * Author: Peng Zhang <zhangpeng.00@bytedance.com> | |
54a611b6 LH |
9 | */ |
10 | ||
11 | /* | |
12 | * DOC: Interesting implementation details of the Maple Tree | |
13 | * | |
14 | * Each node type has a number of slots for entries and a number of slots for | |
15 | * pivots. In the case of dense nodes, the pivots are implied by the position | |
16 | * and are simply the slot index + the minimum of the node. | |
17 | * | |
18 | * In regular B-Tree terms, pivots are called keys. The term pivot is used to | |
d5f6057c RD |
19 | * indicate that the tree is specifying ranges. Pivots may appear in the |
20 | * subtree with an entry attached to the value whereas keys are unique to a | |
54a611b6 LH |
21 | * specific position of a B-tree. Pivot values are inclusive of the slot with |
22 | * the same index. | |
23 | * | |
24 | * | |
25 | * The following illustrates the layout of a range64 nodes slots and pivots. | |
26 | * | |
27 | * | |
28 | * Slots -> | 0 | 1 | 2 | ... | 12 | 13 | 14 | 15 | | |
29 | * ┬ ┬ ┬ ┬ ┬ ┬ ┬ ┬ ┬ | |
30 | * │ │ │ │ │ │ │ │ └─ Implied maximum | |
31 | * │ │ │ │ │ │ │ └─ Pivot 14 | |
32 | * │ │ │ │ │ │ └─ Pivot 13 | |
33 | * │ │ │ │ │ └─ Pivot 12 | |
34 | * │ │ │ │ └─ Pivot 11 | |
35 | * │ │ │ └─ Pivot 2 | |
36 | * │ │ └─ Pivot 1 | |
37 | * │ └─ Pivot 0 | |
38 | * └─ Implied minimum | |
39 | * | |
40 | * Slot contents: | |
41 | * Internal (non-leaf) nodes contain pointers to other nodes. | |
42 | * Leaf nodes contain entries. | |
43 | * | |
44 | * The location of interest is often referred to as an offset. All offsets have | |
45 | * a slot, but the last offset has an implied pivot from the node above (or | |
46 | * UINT_MAX for the root node. | |
47 | * | |
48 | * Ranges complicate certain write activities. When modifying any of | |
49 | * the B-tree variants, it is known that one entry will either be added or | |
50 | * deleted. When modifying the Maple Tree, one store operation may overwrite | |
51 | * the entire data set, or one half of the tree, or the middle half of the tree. | |
52 | * | |
53 | */ | |
54 | ||
55 | ||
56 | #include <linux/maple_tree.h> | |
57 | #include <linux/xarray.h> | |
58 | #include <linux/types.h> | |
59 | #include <linux/export.h> | |
60 | #include <linux/slab.h> | |
61 | #include <linux/limits.h> | |
62 | #include <asm/barrier.h> | |
63 | ||
64 | #define CREATE_TRACE_POINTS | |
65 | #include <trace/events/maple_tree.h> | |
66 | ||
67 | #define MA_ROOT_PARENT 1 | |
68 | ||
69 | /* | |
70 | * Maple state flags | |
71 | * * MA_STATE_BULK - Bulk insert mode | |
72 | * * MA_STATE_REBALANCE - Indicate a rebalance during bulk insert | |
73 | * * MA_STATE_PREALLOC - Preallocated nodes, WARN_ON allocation | |
74 | */ | |
75 | #define MA_STATE_BULK 1 | |
76 | #define MA_STATE_REBALANCE 2 | |
77 | #define MA_STATE_PREALLOC 4 | |
78 | ||
79 | #define ma_parent_ptr(x) ((struct maple_pnode *)(x)) | |
4ffc2ee2 | 80 | #define mas_tree_parent(x) ((unsigned long)(x->tree) | MA_ROOT_PARENT) |
54a611b6 LH |
81 | #define ma_mnode_ptr(x) ((struct maple_node *)(x)) |
82 | #define ma_enode_ptr(x) ((struct maple_enode *)(x)) | |
83 | static struct kmem_cache *maple_node_cache; | |
84 | ||
85 | #ifdef CONFIG_DEBUG_MAPLE_TREE | |
86 | static const unsigned long mt_max[] = { | |
87 | [maple_dense] = MAPLE_NODE_SLOTS, | |
88 | [maple_leaf_64] = ULONG_MAX, | |
89 | [maple_range_64] = ULONG_MAX, | |
90 | [maple_arange_64] = ULONG_MAX, | |
91 | }; | |
92 | #define mt_node_max(x) mt_max[mte_node_type(x)] | |
93 | #endif | |
94 | ||
95 | static const unsigned char mt_slots[] = { | |
96 | [maple_dense] = MAPLE_NODE_SLOTS, | |
97 | [maple_leaf_64] = MAPLE_RANGE64_SLOTS, | |
98 | [maple_range_64] = MAPLE_RANGE64_SLOTS, | |
99 | [maple_arange_64] = MAPLE_ARANGE64_SLOTS, | |
100 | }; | |
101 | #define mt_slot_count(x) mt_slots[mte_node_type(x)] | |
102 | ||
103 | static const unsigned char mt_pivots[] = { | |
104 | [maple_dense] = 0, | |
105 | [maple_leaf_64] = MAPLE_RANGE64_SLOTS - 1, | |
106 | [maple_range_64] = MAPLE_RANGE64_SLOTS - 1, | |
107 | [maple_arange_64] = MAPLE_ARANGE64_SLOTS - 1, | |
108 | }; | |
109 | #define mt_pivot_count(x) mt_pivots[mte_node_type(x)] | |
110 | ||
111 | static const unsigned char mt_min_slots[] = { | |
112 | [maple_dense] = MAPLE_NODE_SLOTS / 2, | |
113 | [maple_leaf_64] = (MAPLE_RANGE64_SLOTS / 2) - 2, | |
114 | [maple_range_64] = (MAPLE_RANGE64_SLOTS / 2) - 2, | |
115 | [maple_arange_64] = (MAPLE_ARANGE64_SLOTS / 2) - 1, | |
116 | }; | |
117 | #define mt_min_slot_count(x) mt_min_slots[mte_node_type(x)] | |
118 | ||
119 | #define MAPLE_BIG_NODE_SLOTS (MAPLE_RANGE64_SLOTS * 2 + 2) | |
120 | #define MAPLE_BIG_NODE_GAPS (MAPLE_ARANGE64_SLOTS * 2 + 1) | |
121 | ||
122 | struct maple_big_node { | |
123 | struct maple_pnode *parent; | |
124 | unsigned long pivot[MAPLE_BIG_NODE_SLOTS - 1]; | |
125 | union { | |
126 | struct maple_enode *slot[MAPLE_BIG_NODE_SLOTS]; | |
127 | struct { | |
128 | unsigned long padding[MAPLE_BIG_NODE_GAPS]; | |
129 | unsigned long gap[MAPLE_BIG_NODE_GAPS]; | |
130 | }; | |
131 | }; | |
132 | unsigned char b_end; | |
133 | enum maple_type type; | |
134 | }; | |
135 | ||
136 | /* | |
137 | * The maple_subtree_state is used to build a tree to replace a segment of an | |
138 | * existing tree in a more atomic way. Any walkers of the older tree will hit a | |
139 | * dead node and restart on updates. | |
140 | */ | |
141 | struct maple_subtree_state { | |
142 | struct ma_state *orig_l; /* Original left side of subtree */ | |
143 | struct ma_state *orig_r; /* Original right side of subtree */ | |
144 | struct ma_state *l; /* New left side of subtree */ | |
145 | struct ma_state *m; /* New middle of subtree (rare) */ | |
146 | struct ma_state *r; /* New right side of subtree */ | |
147 | struct ma_topiary *free; /* nodes to be freed */ | |
148 | struct ma_topiary *destroy; /* Nodes to be destroyed (walked and freed) */ | |
149 | struct maple_big_node *bn; | |
150 | }; | |
151 | ||
44081c77 AB |
152 | #ifdef CONFIG_KASAN_STACK |
153 | /* Prevent mas_wr_bnode() from exceeding the stack frame limit */ | |
154 | #define noinline_for_kasan noinline_for_stack | |
155 | #else | |
156 | #define noinline_for_kasan inline | |
157 | #endif | |
158 | ||
54a611b6 LH |
159 | /* Functions */ |
160 | static inline struct maple_node *mt_alloc_one(gfp_t gfp) | |
161 | { | |
541e06b7 | 162 | return kmem_cache_alloc(maple_node_cache, gfp); |
54a611b6 LH |
163 | } |
164 | ||
165 | static inline int mt_alloc_bulk(gfp_t gfp, size_t size, void **nodes) | |
166 | { | |
541e06b7 | 167 | return kmem_cache_alloc_bulk(maple_node_cache, gfp, size, nodes); |
54a611b6 LH |
168 | } |
169 | ||
4f2267b5 PZ |
170 | static inline void mt_free_one(struct maple_node *node) |
171 | { | |
172 | kmem_cache_free(maple_node_cache, node); | |
173 | } | |
174 | ||
54a611b6 LH |
175 | static inline void mt_free_bulk(size_t size, void __rcu **nodes) |
176 | { | |
177 | kmem_cache_free_bulk(maple_node_cache, size, (void **)nodes); | |
178 | } | |
179 | ||
180 | static void mt_free_rcu(struct rcu_head *head) | |
181 | { | |
182 | struct maple_node *node = container_of(head, struct maple_node, rcu); | |
183 | ||
184 | kmem_cache_free(maple_node_cache, node); | |
185 | } | |
186 | ||
187 | /* | |
188 | * ma_free_rcu() - Use rcu callback to free a maple node | |
189 | * @node: The node to free | |
190 | * | |
191 | * The maple tree uses the parent pointer to indicate this node is no longer in | |
192 | * use and will be freed. | |
193 | */ | |
194 | static void ma_free_rcu(struct maple_node *node) | |
195 | { | |
c13af03d | 196 | WARN_ON(node->parent != ma_parent_ptr(node)); |
54a611b6 LH |
197 | call_rcu(&node->rcu, mt_free_rcu); |
198 | } | |
199 | ||
54a611b6 LH |
200 | static void mas_set_height(struct ma_state *mas) |
201 | { | |
202 | unsigned int new_flags = mas->tree->ma_flags; | |
203 | ||
204 | new_flags &= ~MT_FLAGS_HEIGHT_MASK; | |
5950ada9 | 205 | MAS_BUG_ON(mas, mas->depth > MAPLE_HEIGHT_MAX); |
54a611b6 LH |
206 | new_flags |= mas->depth << MT_FLAGS_HEIGHT_OFFSET; |
207 | mas->tree->ma_flags = new_flags; | |
208 | } | |
209 | ||
210 | static unsigned int mas_mt_height(struct ma_state *mas) | |
211 | { | |
212 | return mt_height(mas->tree); | |
213 | } | |
214 | ||
4f2267b5 PZ |
215 | static inline unsigned int mt_attr(struct maple_tree *mt) |
216 | { | |
217 | return mt->ma_flags & ~MT_FLAGS_HEIGHT_MASK; | |
218 | } | |
219 | ||
271f61a8 LH |
220 | static __always_inline enum maple_type mte_node_type( |
221 | const struct maple_enode *entry) | |
54a611b6 LH |
222 | { |
223 | return ((unsigned long)entry >> MAPLE_NODE_TYPE_SHIFT) & | |
224 | MAPLE_NODE_TYPE_MASK; | |
225 | } | |
226 | ||
271f61a8 | 227 | static __always_inline bool ma_is_dense(const enum maple_type type) |
54a611b6 LH |
228 | { |
229 | return type < maple_leaf_64; | |
230 | } | |
231 | ||
271f61a8 | 232 | static __always_inline bool ma_is_leaf(const enum maple_type type) |
54a611b6 LH |
233 | { |
234 | return type < maple_range_64; | |
235 | } | |
236 | ||
271f61a8 | 237 | static __always_inline bool mte_is_leaf(const struct maple_enode *entry) |
54a611b6 LH |
238 | { |
239 | return ma_is_leaf(mte_node_type(entry)); | |
240 | } | |
241 | ||
242 | /* | |
243 | * We also reserve values with the bottom two bits set to '10' which are | |
244 | * below 4096 | |
245 | */ | |
271f61a8 | 246 | static __always_inline bool mt_is_reserved(const void *entry) |
54a611b6 LH |
247 | { |
248 | return ((unsigned long)entry < MAPLE_RESERVED_RANGE) && | |
249 | xa_is_internal(entry); | |
250 | } | |
251 | ||
067311d3 | 252 | static __always_inline void mas_set_err(struct ma_state *mas, long err) |
54a611b6 LH |
253 | { |
254 | mas->node = MA_ERROR(err); | |
067311d3 | 255 | mas->status = ma_error; |
54a611b6 LH |
256 | } |
257 | ||
067311d3 | 258 | static __always_inline bool mas_is_ptr(const struct ma_state *mas) |
54a611b6 | 259 | { |
067311d3 | 260 | return mas->status == ma_root; |
54a611b6 LH |
261 | } |
262 | ||
067311d3 | 263 | static __always_inline bool mas_is_start(const struct ma_state *mas) |
54a611b6 | 264 | { |
067311d3 | 265 | return mas->status == ma_start; |
54a611b6 LH |
266 | } |
267 | ||
067311d3 | 268 | static __always_inline bool mas_is_none(const struct ma_state *mas) |
54a611b6 | 269 | { |
067311d3 | 270 | return mas->status == ma_none; |
54a611b6 LH |
271 | } |
272 | ||
067311d3 | 273 | static __always_inline bool mas_is_paused(const struct ma_state *mas) |
a8091f03 | 274 | { |
067311d3 | 275 | return mas->status == ma_pause; |
a8091f03 LH |
276 | } |
277 | ||
067311d3 | 278 | static __always_inline bool mas_is_overflow(struct ma_state *mas) |
a8091f03 | 279 | { |
067311d3 LH |
280 | return mas->status == ma_overflow; |
281 | } | |
a8091f03 | 282 | |
067311d3 LH |
283 | static inline bool mas_is_underflow(struct ma_state *mas) |
284 | { | |
285 | return mas->status == ma_underflow; | |
a8091f03 LH |
286 | } |
287 | ||
271f61a8 LH |
288 | static __always_inline struct maple_node *mte_to_node( |
289 | const struct maple_enode *entry) | |
54a611b6 LH |
290 | { |
291 | return (struct maple_node *)((unsigned long)entry & ~MAPLE_NODE_MASK); | |
292 | } | |
293 | ||
294 | /* | |
295 | * mte_to_mat() - Convert a maple encoded node to a maple topiary node. | |
296 | * @entry: The maple encoded node | |
297 | * | |
298 | * Return: a maple topiary pointer | |
299 | */ | |
300 | static inline struct maple_topiary *mte_to_mat(const struct maple_enode *entry) | |
301 | { | |
302 | return (struct maple_topiary *) | |
303 | ((unsigned long)entry & ~MAPLE_NODE_MASK); | |
304 | } | |
305 | ||
306 | /* | |
307 | * mas_mn() - Get the maple state node. | |
308 | * @mas: The maple state | |
309 | * | |
310 | * Return: the maple node (not encoded - bare pointer). | |
311 | */ | |
312 | static inline struct maple_node *mas_mn(const struct ma_state *mas) | |
313 | { | |
314 | return mte_to_node(mas->node); | |
315 | } | |
316 | ||
317 | /* | |
318 | * mte_set_node_dead() - Set a maple encoded node as dead. | |
319 | * @mn: The maple encoded node. | |
320 | */ | |
321 | static inline void mte_set_node_dead(struct maple_enode *mn) | |
322 | { | |
323 | mte_to_node(mn)->parent = ma_parent_ptr(mte_to_node(mn)); | |
324 | smp_wmb(); /* Needed for RCU */ | |
325 | } | |
326 | ||
327 | /* Bit 1 indicates the root is a node */ | |
328 | #define MAPLE_ROOT_NODE 0x02 | |
329 | /* maple_type stored bit 3-6 */ | |
330 | #define MAPLE_ENODE_TYPE_SHIFT 0x03 | |
331 | /* Bit 2 means a NULL somewhere below */ | |
332 | #define MAPLE_ENODE_NULL 0x04 | |
333 | ||
334 | static inline struct maple_enode *mt_mk_node(const struct maple_node *node, | |
335 | enum maple_type type) | |
336 | { | |
337 | return (void *)((unsigned long)node | | |
338 | (type << MAPLE_ENODE_TYPE_SHIFT) | MAPLE_ENODE_NULL); | |
339 | } | |
340 | ||
341 | static inline void *mte_mk_root(const struct maple_enode *node) | |
342 | { | |
343 | return (void *)((unsigned long)node | MAPLE_ROOT_NODE); | |
344 | } | |
345 | ||
346 | static inline void *mte_safe_root(const struct maple_enode *node) | |
347 | { | |
348 | return (void *)((unsigned long)node & ~MAPLE_ROOT_NODE); | |
349 | } | |
350 | ||
6e7ba8b5 | 351 | static inline void *mte_set_full(const struct maple_enode *node) |
54a611b6 | 352 | { |
6e7ba8b5 | 353 | return (void *)((unsigned long)node & ~MAPLE_ENODE_NULL); |
54a611b6 LH |
354 | } |
355 | ||
6e7ba8b5 | 356 | static inline void *mte_clear_full(const struct maple_enode *node) |
54a611b6 | 357 | { |
6e7ba8b5 LH |
358 | return (void *)((unsigned long)node | MAPLE_ENODE_NULL); |
359 | } | |
360 | ||
361 | static inline bool mte_has_null(const struct maple_enode *node) | |
362 | { | |
363 | return (unsigned long)node & MAPLE_ENODE_NULL; | |
54a611b6 LH |
364 | } |
365 | ||
271f61a8 | 366 | static __always_inline bool ma_is_root(struct maple_node *node) |
54a611b6 LH |
367 | { |
368 | return ((unsigned long)node->parent & MA_ROOT_PARENT); | |
369 | } | |
370 | ||
271f61a8 | 371 | static __always_inline bool mte_is_root(const struct maple_enode *node) |
54a611b6 LH |
372 | { |
373 | return ma_is_root(mte_to_node(node)); | |
374 | } | |
375 | ||
376 | static inline bool mas_is_root_limits(const struct ma_state *mas) | |
377 | { | |
378 | return !mas->min && mas->max == ULONG_MAX; | |
379 | } | |
380 | ||
271f61a8 | 381 | static __always_inline bool mt_is_alloc(struct maple_tree *mt) |
54a611b6 LH |
382 | { |
383 | return (mt->ma_flags & MT_FLAGS_ALLOC_RANGE); | |
384 | } | |
385 | ||
386 | /* | |
387 | * The Parent Pointer | |
388 | * Excluding root, the parent pointer is 256B aligned like all other tree nodes. | |
389 | * When storing a 32 or 64 bit values, the offset can fit into 5 bits. The 16 | |
390 | * bit values need an extra bit to store the offset. This extra bit comes from | |
391 | * a reuse of the last bit in the node type. This is possible by using bit 1 to | |
392 | * indicate if bit 2 is part of the type or the slot. | |
393 | * | |
394 | * Note types: | |
395 | * 0x??1 = Root | |
396 | * 0x?00 = 16 bit nodes | |
397 | * 0x010 = 32 bit nodes | |
398 | * 0x110 = 64 bit nodes | |
399 | * | |
400 | * Slot size and alignment | |
401 | * 0b??1 : Root | |
402 | * 0b?00 : 16 bit values, type in 0-1, slot in 2-7 | |
403 | * 0b010 : 32 bit values, type in 0-2, slot in 3-7 | |
404 | * 0b110 : 64 bit values, type in 0-2, slot in 3-7 | |
405 | */ | |
406 | ||
407 | #define MAPLE_PARENT_ROOT 0x01 | |
408 | ||
409 | #define MAPLE_PARENT_SLOT_SHIFT 0x03 | |
410 | #define MAPLE_PARENT_SLOT_MASK 0xF8 | |
411 | ||
412 | #define MAPLE_PARENT_16B_SLOT_SHIFT 0x02 | |
413 | #define MAPLE_PARENT_16B_SLOT_MASK 0xFC | |
414 | ||
415 | #define MAPLE_PARENT_RANGE64 0x06 | |
416 | #define MAPLE_PARENT_RANGE32 0x04 | |
417 | #define MAPLE_PARENT_NOT_RANGE16 0x02 | |
418 | ||
419 | /* | |
420 | * mte_parent_shift() - Get the parent shift for the slot storage. | |
421 | * @parent: The parent pointer cast as an unsigned long | |
422 | * Return: The shift into that pointer to the star to of the slot | |
423 | */ | |
424 | static inline unsigned long mte_parent_shift(unsigned long parent) | |
425 | { | |
426 | /* Note bit 1 == 0 means 16B */ | |
427 | if (likely(parent & MAPLE_PARENT_NOT_RANGE16)) | |
428 | return MAPLE_PARENT_SLOT_SHIFT; | |
429 | ||
430 | return MAPLE_PARENT_16B_SLOT_SHIFT; | |
431 | } | |
432 | ||
433 | /* | |
434 | * mte_parent_slot_mask() - Get the slot mask for the parent. | |
435 | * @parent: The parent pointer cast as an unsigned long. | |
436 | * Return: The slot mask for that parent. | |
437 | */ | |
438 | static inline unsigned long mte_parent_slot_mask(unsigned long parent) | |
439 | { | |
440 | /* Note bit 1 == 0 means 16B */ | |
441 | if (likely(parent & MAPLE_PARENT_NOT_RANGE16)) | |
442 | return MAPLE_PARENT_SLOT_MASK; | |
443 | ||
444 | return MAPLE_PARENT_16B_SLOT_MASK; | |
445 | } | |
446 | ||
447 | /* | |
afc754c6 | 448 | * mas_parent_type() - Return the maple_type of the parent from the stored |
54a611b6 LH |
449 | * parent type. |
450 | * @mas: The maple state | |
afc754c6 | 451 | * @enode: The maple_enode to extract the parent's enum |
54a611b6 LH |
452 | * Return: The node->parent maple_type |
453 | */ | |
454 | static inline | |
afc754c6 | 455 | enum maple_type mas_parent_type(struct ma_state *mas, struct maple_enode *enode) |
54a611b6 LH |
456 | { |
457 | unsigned long p_type; | |
458 | ||
afc754c6 LH |
459 | p_type = (unsigned long)mte_to_node(enode)->parent; |
460 | if (WARN_ON(p_type & MAPLE_PARENT_ROOT)) | |
461 | return 0; | |
54a611b6 LH |
462 | |
463 | p_type &= MAPLE_NODE_MASK; | |
afc754c6 | 464 | p_type &= ~mte_parent_slot_mask(p_type); |
54a611b6 LH |
465 | switch (p_type) { |
466 | case MAPLE_PARENT_RANGE64: /* or MAPLE_PARENT_ARANGE64 */ | |
afc754c6 | 467 | if (mt_is_alloc(mas->tree)) |
54a611b6 LH |
468 | return maple_arange_64; |
469 | return maple_range_64; | |
470 | } | |
471 | ||
472 | return 0; | |
473 | } | |
474 | ||
54a611b6 | 475 | /* |
bf96715e | 476 | * mas_set_parent() - Set the parent node and encode the slot |
54a611b6 LH |
477 | * @enode: The encoded maple node. |
478 | * @parent: The encoded maple node that is the parent of @enode. | |
479 | * @slot: The slot that @enode resides in @parent. | |
480 | * | |
481 | * Slot number is encoded in the enode->parent bit 3-6 or 2-6, depending on the | |
482 | * parent type. | |
483 | */ | |
484 | static inline | |
bf96715e LH |
485 | void mas_set_parent(struct ma_state *mas, struct maple_enode *enode, |
486 | const struct maple_enode *parent, unsigned char slot) | |
54a611b6 | 487 | { |
831978e3 | 488 | unsigned long val = (unsigned long)parent; |
54a611b6 LH |
489 | unsigned long shift; |
490 | unsigned long type; | |
491 | enum maple_type p_type = mte_node_type(parent); | |
492 | ||
bf96715e LH |
493 | MAS_BUG_ON(mas, p_type == maple_dense); |
494 | MAS_BUG_ON(mas, p_type == maple_leaf_64); | |
54a611b6 LH |
495 | |
496 | switch (p_type) { | |
497 | case maple_range_64: | |
498 | case maple_arange_64: | |
499 | shift = MAPLE_PARENT_SLOT_SHIFT; | |
500 | type = MAPLE_PARENT_RANGE64; | |
501 | break; | |
502 | default: | |
503 | case maple_dense: | |
504 | case maple_leaf_64: | |
505 | shift = type = 0; | |
506 | break; | |
507 | } | |
508 | ||
509 | val &= ~MAPLE_NODE_MASK; /* Clear all node metadata in parent */ | |
510 | val |= (slot << shift) | type; | |
511 | mte_to_node(enode)->parent = ma_parent_ptr(val); | |
512 | } | |
513 | ||
514 | /* | |
515 | * mte_parent_slot() - get the parent slot of @enode. | |
516 | * @enode: The encoded maple node. | |
517 | * | |
518 | * Return: The slot in the parent node where @enode resides. | |
519 | */ | |
271f61a8 LH |
520 | static __always_inline |
521 | unsigned int mte_parent_slot(const struct maple_enode *enode) | |
54a611b6 | 522 | { |
831978e3 | 523 | unsigned long val = (unsigned long)mte_to_node(enode)->parent; |
54a611b6 | 524 | |
271f61a8 | 525 | if (unlikely(val & MA_ROOT_PARENT)) |
54a611b6 LH |
526 | return 0; |
527 | ||
528 | /* | |
529 | * Okay to use MAPLE_PARENT_16B_SLOT_MASK as the last bit will be lost | |
530 | * by shift if the parent shift is MAPLE_PARENT_SLOT_SHIFT | |
531 | */ | |
532 | return (val & MAPLE_PARENT_16B_SLOT_MASK) >> mte_parent_shift(val); | |
533 | } | |
534 | ||
535 | /* | |
536 | * mte_parent() - Get the parent of @node. | |
537 | * @node: The encoded maple node. | |
538 | * | |
539 | * Return: The parent maple node. | |
540 | */ | |
271f61a8 LH |
541 | static __always_inline |
542 | struct maple_node *mte_parent(const struct maple_enode *enode) | |
54a611b6 LH |
543 | { |
544 | return (void *)((unsigned long) | |
545 | (mte_to_node(enode)->parent) & ~MAPLE_NODE_MASK); | |
546 | } | |
547 | ||
548 | /* | |
549 | * ma_dead_node() - check if the @enode is dead. | |
550 | * @enode: The encoded maple node | |
551 | * | |
552 | * Return: true if dead, false otherwise. | |
553 | */ | |
271f61a8 | 554 | static __always_inline bool ma_dead_node(const struct maple_node *node) |
54a611b6 | 555 | { |
0a2b18d9 | 556 | struct maple_node *parent; |
54a611b6 | 557 | |
0a2b18d9 LH |
558 | /* Do not reorder reads from the node prior to the parent check */ |
559 | smp_rmb(); | |
560 | parent = (void *)((unsigned long) node->parent & ~MAPLE_NODE_MASK); | |
54a611b6 LH |
561 | return (parent == node); |
562 | } | |
39d0bd86 | 563 | |
54a611b6 LH |
564 | /* |
565 | * mte_dead_node() - check if the @enode is dead. | |
566 | * @enode: The encoded maple node | |
567 | * | |
568 | * Return: true if dead, false otherwise. | |
569 | */ | |
271f61a8 | 570 | static __always_inline bool mte_dead_node(const struct maple_enode *enode) |
54a611b6 LH |
571 | { |
572 | struct maple_node *parent, *node; | |
573 | ||
574 | node = mte_to_node(enode); | |
0a2b18d9 LH |
575 | /* Do not reorder reads from the node prior to the parent check */ |
576 | smp_rmb(); | |
54a611b6 LH |
577 | parent = mte_parent(enode); |
578 | return (parent == node); | |
579 | } | |
580 | ||
581 | /* | |
582 | * mas_allocated() - Get the number of nodes allocated in a maple state. | |
583 | * @mas: The maple state | |
584 | * | |
585 | * The ma_state alloc member is overloaded to hold a pointer to the first | |
586 | * allocated node or to the number of requested nodes to allocate. If bit 0 is | |
587 | * set, then the alloc contains the number of requested nodes. If there is an | |
588 | * allocated node, then the total allocated nodes is in that node. | |
589 | * | |
590 | * Return: The total number of nodes allocated | |
591 | */ | |
592 | static inline unsigned long mas_allocated(const struct ma_state *mas) | |
593 | { | |
594 | if (!mas->alloc || ((unsigned long)mas->alloc & 0x1)) | |
595 | return 0; | |
596 | ||
597 | return mas->alloc->total; | |
598 | } | |
599 | ||
600 | /* | |
601 | * mas_set_alloc_req() - Set the requested number of allocations. | |
602 | * @mas: the maple state | |
603 | * @count: the number of allocations. | |
604 | * | |
605 | * The requested number of allocations is either in the first allocated node, | |
606 | * located in @mas->alloc->request_count, or directly in @mas->alloc if there is | |
607 | * no allocated node. Set the request either in the node or do the necessary | |
608 | * encoding to store in @mas->alloc directly. | |
609 | */ | |
610 | static inline void mas_set_alloc_req(struct ma_state *mas, unsigned long count) | |
611 | { | |
612 | if (!mas->alloc || ((unsigned long)mas->alloc & 0x1)) { | |
613 | if (!count) | |
614 | mas->alloc = NULL; | |
615 | else | |
616 | mas->alloc = (struct maple_alloc *)(((count) << 1U) | 1U); | |
617 | return; | |
618 | } | |
619 | ||
620 | mas->alloc->request_count = count; | |
621 | } | |
622 | ||
623 | /* | |
624 | * mas_alloc_req() - get the requested number of allocations. | |
625 | * @mas: The maple state | |
626 | * | |
627 | * The alloc count is either stored directly in @mas, or in | |
628 | * @mas->alloc->request_count if there is at least one node allocated. Decode | |
629 | * the request count if it's stored directly in @mas->alloc. | |
630 | * | |
631 | * Return: The allocation request count. | |
632 | */ | |
633 | static inline unsigned int mas_alloc_req(const struct ma_state *mas) | |
634 | { | |
635 | if ((unsigned long)mas->alloc & 0x1) | |
636 | return (unsigned long)(mas->alloc) >> 1; | |
637 | else if (mas->alloc) | |
638 | return mas->alloc->request_count; | |
639 | return 0; | |
640 | } | |
641 | ||
642 | /* | |
643 | * ma_pivots() - Get a pointer to the maple node pivots. | |
644 | * @node - the maple node | |
645 | * @type - the node type | |
646 | * | |
39d0bd86 LH |
647 | * In the event of a dead node, this array may be %NULL |
648 | * | |
54a611b6 LH |
649 | * Return: A pointer to the maple node pivots |
650 | */ | |
651 | static inline unsigned long *ma_pivots(struct maple_node *node, | |
652 | enum maple_type type) | |
653 | { | |
654 | switch (type) { | |
655 | case maple_arange_64: | |
656 | return node->ma64.pivot; | |
657 | case maple_range_64: | |
658 | case maple_leaf_64: | |
659 | return node->mr64.pivot; | |
660 | case maple_dense: | |
661 | return NULL; | |
662 | } | |
663 | return NULL; | |
664 | } | |
665 | ||
666 | /* | |
667 | * ma_gaps() - Get a pointer to the maple node gaps. | |
668 | * @node - the maple node | |
669 | * @type - the node type | |
670 | * | |
671 | * Return: A pointer to the maple node gaps | |
672 | */ | |
673 | static inline unsigned long *ma_gaps(struct maple_node *node, | |
674 | enum maple_type type) | |
675 | { | |
676 | switch (type) { | |
677 | case maple_arange_64: | |
678 | return node->ma64.gap; | |
679 | case maple_range_64: | |
680 | case maple_leaf_64: | |
681 | case maple_dense: | |
682 | return NULL; | |
683 | } | |
684 | return NULL; | |
685 | } | |
686 | ||
54a611b6 LH |
687 | /* |
688 | * mas_safe_pivot() - get the pivot at @piv or mas->max. | |
689 | * @mas: The maple state | |
690 | * @pivots: The pointer to the maple node pivots | |
691 | * @piv: The pivot to fetch | |
692 | * @type: The maple node type | |
693 | * | |
694 | * Return: The pivot at @piv within the limit of the @pivots array, @mas->max | |
695 | * otherwise. | |
696 | */ | |
271f61a8 | 697 | static __always_inline unsigned long |
54a611b6 LH |
698 | mas_safe_pivot(const struct ma_state *mas, unsigned long *pivots, |
699 | unsigned char piv, enum maple_type type) | |
700 | { | |
701 | if (piv >= mt_pivots[type]) | |
702 | return mas->max; | |
703 | ||
704 | return pivots[piv]; | |
705 | } | |
706 | ||
707 | /* | |
708 | * mas_safe_min() - Return the minimum for a given offset. | |
709 | * @mas: The maple state | |
710 | * @pivots: The pointer to the maple node pivots | |
711 | * @offset: The offset into the pivot array | |
712 | * | |
713 | * Return: The minimum range value that is contained in @offset. | |
714 | */ | |
715 | static inline unsigned long | |
716 | mas_safe_min(struct ma_state *mas, unsigned long *pivots, unsigned char offset) | |
717 | { | |
718 | if (likely(offset)) | |
719 | return pivots[offset - 1] + 1; | |
720 | ||
721 | return mas->min; | |
722 | } | |
723 | ||
54a611b6 LH |
724 | /* |
725 | * mte_set_pivot() - Set a pivot to a value in an encoded maple node. | |
726 | * @mn: The encoded maple node | |
727 | * @piv: The pivot offset | |
728 | * @val: The value of the pivot | |
729 | */ | |
730 | static inline void mte_set_pivot(struct maple_enode *mn, unsigned char piv, | |
731 | unsigned long val) | |
732 | { | |
733 | struct maple_node *node = mte_to_node(mn); | |
734 | enum maple_type type = mte_node_type(mn); | |
735 | ||
736 | BUG_ON(piv >= mt_pivots[type]); | |
737 | switch (type) { | |
54a611b6 LH |
738 | case maple_range_64: |
739 | case maple_leaf_64: | |
740 | node->mr64.pivot[piv] = val; | |
741 | break; | |
742 | case maple_arange_64: | |
743 | node->ma64.pivot[piv] = val; | |
744 | break; | |
745 | case maple_dense: | |
746 | break; | |
747 | } | |
748 | ||
749 | } | |
750 | ||
751 | /* | |
752 | * ma_slots() - Get a pointer to the maple node slots. | |
753 | * @mn: The maple node | |
754 | * @mt: The maple node type | |
755 | * | |
756 | * Return: A pointer to the maple node slots | |
757 | */ | |
758 | static inline void __rcu **ma_slots(struct maple_node *mn, enum maple_type mt) | |
759 | { | |
760 | switch (mt) { | |
54a611b6 LH |
761 | case maple_arange_64: |
762 | return mn->ma64.slot; | |
763 | case maple_range_64: | |
764 | case maple_leaf_64: | |
765 | return mn->mr64.slot; | |
766 | case maple_dense: | |
767 | return mn->slot; | |
768 | } | |
37a8ab24 LH |
769 | |
770 | return NULL; | |
54a611b6 LH |
771 | } |
772 | ||
19a462f0 LH |
773 | static inline bool mt_write_locked(const struct maple_tree *mt) |
774 | { | |
775 | return mt_external_lock(mt) ? mt_write_lock_is_held(mt) : | |
776 | lockdep_is_held(&mt->ma_lock); | |
777 | } | |
778 | ||
271f61a8 | 779 | static __always_inline bool mt_locked(const struct maple_tree *mt) |
54a611b6 LH |
780 | { |
781 | return mt_external_lock(mt) ? mt_lock_is_held(mt) : | |
782 | lockdep_is_held(&mt->ma_lock); | |
783 | } | |
784 | ||
271f61a8 | 785 | static __always_inline void *mt_slot(const struct maple_tree *mt, |
54a611b6 LH |
786 | void __rcu **slots, unsigned char offset) |
787 | { | |
788 | return rcu_dereference_check(slots[offset], mt_locked(mt)); | |
789 | } | |
790 | ||
271f61a8 LH |
791 | static __always_inline void *mt_slot_locked(struct maple_tree *mt, |
792 | void __rcu **slots, unsigned char offset) | |
790e1fa8 | 793 | { |
19a462f0 | 794 | return rcu_dereference_protected(slots[offset], mt_write_locked(mt)); |
790e1fa8 | 795 | } |
54a611b6 LH |
796 | /* |
797 | * mas_slot_locked() - Get the slot value when holding the maple tree lock. | |
798 | * @mas: The maple state | |
799 | * @slots: The pointer to the slots | |
800 | * @offset: The offset into the slots array to fetch | |
801 | * | |
802 | * Return: The entry stored in @slots at the @offset. | |
803 | */ | |
271f61a8 LH |
804 | static __always_inline void *mas_slot_locked(struct ma_state *mas, |
805 | void __rcu **slots, unsigned char offset) | |
54a611b6 | 806 | { |
790e1fa8 | 807 | return mt_slot_locked(mas->tree, slots, offset); |
54a611b6 LH |
808 | } |
809 | ||
810 | /* | |
811 | * mas_slot() - Get the slot value when not holding the maple tree lock. | |
812 | * @mas: The maple state | |
813 | * @slots: The pointer to the slots | |
814 | * @offset: The offset into the slots array to fetch | |
815 | * | |
816 | * Return: The entry stored in @slots at the @offset | |
817 | */ | |
271f61a8 LH |
818 | static __always_inline void *mas_slot(struct ma_state *mas, void __rcu **slots, |
819 | unsigned char offset) | |
54a611b6 LH |
820 | { |
821 | return mt_slot(mas->tree, slots, offset); | |
822 | } | |
823 | ||
824 | /* | |
825 | * mas_root() - Get the maple tree root. | |
826 | * @mas: The maple state. | |
827 | * | |
828 | * Return: The pointer to the root of the tree | |
829 | */ | |
271f61a8 | 830 | static __always_inline void *mas_root(struct ma_state *mas) |
54a611b6 LH |
831 | { |
832 | return rcu_dereference_check(mas->tree->ma_root, mt_locked(mas->tree)); | |
833 | } | |
834 | ||
835 | static inline void *mt_root_locked(struct maple_tree *mt) | |
836 | { | |
19a462f0 | 837 | return rcu_dereference_protected(mt->ma_root, mt_write_locked(mt)); |
54a611b6 LH |
838 | } |
839 | ||
840 | /* | |
841 | * mas_root_locked() - Get the maple tree root when holding the maple tree lock. | |
842 | * @mas: The maple state. | |
843 | * | |
844 | * Return: The pointer to the root of the tree | |
845 | */ | |
846 | static inline void *mas_root_locked(struct ma_state *mas) | |
847 | { | |
848 | return mt_root_locked(mas->tree); | |
849 | } | |
850 | ||
851 | static inline struct maple_metadata *ma_meta(struct maple_node *mn, | |
852 | enum maple_type mt) | |
853 | { | |
854 | switch (mt) { | |
855 | case maple_arange_64: | |
856 | return &mn->ma64.meta; | |
857 | default: | |
858 | return &mn->mr64.meta; | |
859 | } | |
860 | } | |
861 | ||
862 | /* | |
863 | * ma_set_meta() - Set the metadata information of a node. | |
864 | * @mn: The maple node | |
865 | * @mt: The maple node type | |
866 | * @offset: The offset of the highest sub-gap in this node. | |
867 | * @end: The end of the data in this node. | |
868 | */ | |
869 | static inline void ma_set_meta(struct maple_node *mn, enum maple_type mt, | |
870 | unsigned char offset, unsigned char end) | |
871 | { | |
872 | struct maple_metadata *meta = ma_meta(mn, mt); | |
873 | ||
874 | meta->gap = offset; | |
875 | meta->end = end; | |
876 | } | |
877 | ||
2e5b4921 | 878 | /* |
790e1fa8 LH |
879 | * mt_clear_meta() - clear the metadata information of a node, if it exists |
880 | * @mt: The maple tree | |
2e5b4921 | 881 | * @mn: The maple node |
790e1fa8 | 882 | * @type: The maple node type |
2e5b4921 LH |
883 | * @offset: The offset of the highest sub-gap in this node. |
884 | * @end: The end of the data in this node. | |
885 | */ | |
790e1fa8 LH |
886 | static inline void mt_clear_meta(struct maple_tree *mt, struct maple_node *mn, |
887 | enum maple_type type) | |
2e5b4921 LH |
888 | { |
889 | struct maple_metadata *meta; | |
890 | unsigned long *pivots; | |
891 | void __rcu **slots; | |
892 | void *next; | |
893 | ||
790e1fa8 | 894 | switch (type) { |
2e5b4921 LH |
895 | case maple_range_64: |
896 | pivots = mn->mr64.pivot; | |
897 | if (unlikely(pivots[MAPLE_RANGE64_SLOTS - 2])) { | |
898 | slots = mn->mr64.slot; | |
790e1fa8 LH |
899 | next = mt_slot_locked(mt, slots, |
900 | MAPLE_RANGE64_SLOTS - 1); | |
901 | if (unlikely((mte_to_node(next) && | |
902 | mte_node_type(next)))) | |
903 | return; /* no metadata, could be node */ | |
2e5b4921 LH |
904 | } |
905 | fallthrough; | |
906 | case maple_arange_64: | |
790e1fa8 | 907 | meta = ma_meta(mn, type); |
2e5b4921 LH |
908 | break; |
909 | default: | |
910 | return; | |
911 | } | |
912 | ||
913 | meta->gap = 0; | |
914 | meta->end = 0; | |
915 | } | |
916 | ||
54a611b6 LH |
917 | /* |
918 | * ma_meta_end() - Get the data end of a node from the metadata | |
919 | * @mn: The maple node | |
920 | * @mt: The maple node type | |
921 | */ | |
922 | static inline unsigned char ma_meta_end(struct maple_node *mn, | |
923 | enum maple_type mt) | |
924 | { | |
925 | struct maple_metadata *meta = ma_meta(mn, mt); | |
926 | ||
927 | return meta->end; | |
928 | } | |
929 | ||
930 | /* | |
931 | * ma_meta_gap() - Get the largest gap location of a node from the metadata | |
932 | * @mn: The maple node | |
54a611b6 | 933 | */ |
c5e94121 | 934 | static inline unsigned char ma_meta_gap(struct maple_node *mn) |
54a611b6 | 935 | { |
54a611b6 LH |
936 | return mn->ma64.meta.gap; |
937 | } | |
938 | ||
939 | /* | |
940 | * ma_set_meta_gap() - Set the largest gap location in a nodes metadata | |
941 | * @mn: The maple node | |
942 | * @mn: The maple node type | |
943 | * @offset: The location of the largest gap. | |
944 | */ | |
945 | static inline void ma_set_meta_gap(struct maple_node *mn, enum maple_type mt, | |
946 | unsigned char offset) | |
947 | { | |
948 | ||
949 | struct maple_metadata *meta = ma_meta(mn, mt); | |
950 | ||
951 | meta->gap = offset; | |
952 | } | |
953 | ||
954 | /* | |
955 | * mat_add() - Add a @dead_enode to the ma_topiary of a list of dead nodes. | |
956 | * @mat - the ma_topiary, a linked list of dead nodes. | |
957 | * @dead_enode - the node to be marked as dead and added to the tail of the list | |
958 | * | |
959 | * Add the @dead_enode to the linked list in @mat. | |
960 | */ | |
961 | static inline void mat_add(struct ma_topiary *mat, | |
962 | struct maple_enode *dead_enode) | |
963 | { | |
964 | mte_set_node_dead(dead_enode); | |
965 | mte_to_mat(dead_enode)->next = NULL; | |
966 | if (!mat->tail) { | |
967 | mat->tail = mat->head = dead_enode; | |
968 | return; | |
969 | } | |
970 | ||
971 | mte_to_mat(mat->tail)->next = dead_enode; | |
972 | mat->tail = dead_enode; | |
973 | } | |
974 | ||
530f745c LH |
975 | static void mt_free_walk(struct rcu_head *head); |
976 | static void mt_destroy_walk(struct maple_enode *enode, struct maple_tree *mt, | |
977 | bool free); | |
54a611b6 LH |
978 | /* |
979 | * mas_mat_destroy() - Free all nodes and subtrees in a dead list. | |
980 | * @mas - the maple state | |
981 | * @mat - the ma_topiary linked list of dead nodes to free. | |
982 | * | |
983 | * Destroy walk a dead list. | |
984 | */ | |
985 | static void mas_mat_destroy(struct ma_state *mas, struct ma_topiary *mat) | |
986 | { | |
987 | struct maple_enode *next; | |
530f745c LH |
988 | struct maple_node *node; |
989 | bool in_rcu = mt_in_rcu(mas->tree); | |
54a611b6 LH |
990 | |
991 | while (mat->head) { | |
992 | next = mte_to_mat(mat->head)->next; | |
530f745c LH |
993 | node = mte_to_node(mat->head); |
994 | mt_destroy_walk(mat->head, mas->tree, !in_rcu); | |
995 | if (in_rcu) | |
996 | call_rcu(&node->rcu, mt_free_walk); | |
54a611b6 LH |
997 | mat->head = next; |
998 | } | |
999 | } | |
1000 | /* | |
1001 | * mas_descend() - Descend into the slot stored in the ma_state. | |
1002 | * @mas - the maple state. | |
1003 | * | |
1004 | * Note: Not RCU safe, only use in write side or debug code. | |
1005 | */ | |
1006 | static inline void mas_descend(struct ma_state *mas) | |
1007 | { | |
1008 | enum maple_type type; | |
1009 | unsigned long *pivots; | |
1010 | struct maple_node *node; | |
1011 | void __rcu **slots; | |
1012 | ||
1013 | node = mas_mn(mas); | |
1014 | type = mte_node_type(mas->node); | |
1015 | pivots = ma_pivots(node, type); | |
1016 | slots = ma_slots(node, type); | |
1017 | ||
1018 | if (mas->offset) | |
1019 | mas->min = pivots[mas->offset - 1] + 1; | |
1020 | mas->max = mas_safe_pivot(mas, pivots, mas->offset, type); | |
1021 | mas->node = mas_slot(mas, slots, mas->offset); | |
1022 | } | |
1023 | ||
1024 | /* | |
1025 | * mte_set_gap() - Set a maple node gap. | |
1026 | * @mn: The encoded maple node | |
1027 | * @gap: The offset of the gap to set | |
1028 | * @val: The gap value | |
1029 | */ | |
1030 | static inline void mte_set_gap(const struct maple_enode *mn, | |
1031 | unsigned char gap, unsigned long val) | |
1032 | { | |
1033 | switch (mte_node_type(mn)) { | |
1034 | default: | |
1035 | break; | |
1036 | case maple_arange_64: | |
1037 | mte_to_node(mn)->ma64.gap[gap] = val; | |
1038 | break; | |
1039 | } | |
1040 | } | |
1041 | ||
1042 | /* | |
1043 | * mas_ascend() - Walk up a level of the tree. | |
1044 | * @mas: The maple state | |
1045 | * | |
1046 | * Sets the @mas->max and @mas->min to the correct values when walking up. This | |
1047 | * may cause several levels of walking up to find the correct min and max. | |
1048 | * May find a dead node which will cause a premature return. | |
1049 | * Return: 1 on dead node, 0 otherwise | |
1050 | */ | |
1051 | static int mas_ascend(struct ma_state *mas) | |
1052 | { | |
1053 | struct maple_enode *p_enode; /* parent enode. */ | |
1054 | struct maple_enode *a_enode; /* ancestor enode. */ | |
1055 | struct maple_node *a_node; /* ancestor node. */ | |
1056 | struct maple_node *p_node; /* parent node. */ | |
1057 | unsigned char a_slot; | |
1058 | enum maple_type a_type; | |
1059 | unsigned long min, max; | |
1060 | unsigned long *pivots; | |
54a611b6 LH |
1061 | bool set_max = false, set_min = false; |
1062 | ||
1063 | a_node = mas_mn(mas); | |
1064 | if (ma_is_root(a_node)) { | |
1065 | mas->offset = 0; | |
1066 | return 0; | |
1067 | } | |
1068 | ||
1069 | p_node = mte_parent(mas->node); | |
1070 | if (unlikely(a_node == p_node)) | |
1071 | return 1; | |
633769c9 | 1072 | |
afc754c6 | 1073 | a_type = mas_parent_type(mas, mas->node); |
633769c9 | 1074 | mas->offset = mte_parent_slot(mas->node); |
54a611b6 LH |
1075 | a_enode = mt_mk_node(p_node, a_type); |
1076 | ||
1077 | /* Check to make sure all parent information is still accurate */ | |
1078 | if (p_node != mte_parent(mas->node)) | |
1079 | return 1; | |
1080 | ||
1081 | mas->node = a_enode; | |
54a611b6 LH |
1082 | |
1083 | if (mte_is_root(a_enode)) { | |
1084 | mas->max = ULONG_MAX; | |
1085 | mas->min = 0; | |
1086 | return 0; | |
1087 | } | |
1088 | ||
3f05fcde PZ |
1089 | min = 0; |
1090 | max = ULONG_MAX; | |
1091 | if (!mas->offset) { | |
1092 | min = mas->min; | |
633769c9 | 1093 | set_min = true; |
3f05fcde | 1094 | } |
633769c9 LH |
1095 | |
1096 | if (mas->max == ULONG_MAX) | |
1097 | set_max = true; | |
1098 | ||
54a611b6 LH |
1099 | do { |
1100 | p_enode = a_enode; | |
afc754c6 | 1101 | a_type = mas_parent_type(mas, p_enode); |
54a611b6 LH |
1102 | a_node = mte_parent(p_enode); |
1103 | a_slot = mte_parent_slot(p_enode); | |
54a611b6 | 1104 | a_enode = mt_mk_node(a_node, a_type); |
39d0bd86 LH |
1105 | pivots = ma_pivots(a_node, a_type); |
1106 | ||
1107 | if (unlikely(ma_dead_node(a_node))) | |
1108 | return 1; | |
54a611b6 LH |
1109 | |
1110 | if (!set_min && a_slot) { | |
1111 | set_min = true; | |
1112 | min = pivots[a_slot - 1] + 1; | |
1113 | } | |
1114 | ||
1115 | if (!set_max && a_slot < mt_pivots[a_type]) { | |
1116 | set_max = true; | |
1117 | max = pivots[a_slot]; | |
1118 | } | |
1119 | ||
1120 | if (unlikely(ma_dead_node(a_node))) | |
1121 | return 1; | |
1122 | ||
1123 | if (unlikely(ma_is_root(a_node))) | |
1124 | break; | |
1125 | ||
1126 | } while (!set_min || !set_max); | |
1127 | ||
1128 | mas->max = max; | |
1129 | mas->min = min; | |
1130 | return 0; | |
1131 | } | |
1132 | ||
1133 | /* | |
1134 | * mas_pop_node() - Get a previously allocated maple node from the maple state. | |
1135 | * @mas: The maple state | |
1136 | * | |
1137 | * Return: A pointer to a maple node. | |
1138 | */ | |
1139 | static inline struct maple_node *mas_pop_node(struct ma_state *mas) | |
1140 | { | |
1141 | struct maple_alloc *ret, *node = mas->alloc; | |
1142 | unsigned long total = mas_allocated(mas); | |
541e06b7 | 1143 | unsigned int req = mas_alloc_req(mas); |
54a611b6 LH |
1144 | |
1145 | /* nothing or a request pending. */ | |
541e06b7 | 1146 | if (WARN_ON(!total)) |
54a611b6 LH |
1147 | return NULL; |
1148 | ||
1149 | if (total == 1) { | |
1150 | /* single allocation in this ma_state */ | |
1151 | mas->alloc = NULL; | |
1152 | ret = node; | |
1153 | goto single_node; | |
1154 | } | |
1155 | ||
541e06b7 | 1156 | if (node->node_count == 1) { |
54a611b6 LH |
1157 | /* Single allocation in this node. */ |
1158 | mas->alloc = node->slot[0]; | |
54a611b6 LH |
1159 | mas->alloc->total = node->total - 1; |
1160 | ret = node; | |
1161 | goto new_head; | |
1162 | } | |
54a611b6 | 1163 | node->total--; |
541e06b7 LH |
1164 | ret = node->slot[--node->node_count]; |
1165 | node->slot[node->node_count] = NULL; | |
54a611b6 LH |
1166 | |
1167 | single_node: | |
1168 | new_head: | |
541e06b7 LH |
1169 | if (req) { |
1170 | req++; | |
1171 | mas_set_alloc_req(mas, req); | |
54a611b6 | 1172 | } |
541e06b7 LH |
1173 | |
1174 | memset(ret, 0, sizeof(*ret)); | |
54a611b6 LH |
1175 | return (struct maple_node *)ret; |
1176 | } | |
1177 | ||
1178 | /* | |
1179 | * mas_push_node() - Push a node back on the maple state allocation. | |
1180 | * @mas: The maple state | |
1181 | * @used: The used maple node | |
1182 | * | |
1183 | * Stores the maple node back into @mas->alloc for reuse. Updates allocated and | |
1184 | * requested node count as necessary. | |
1185 | */ | |
1186 | static inline void mas_push_node(struct ma_state *mas, struct maple_node *used) | |
1187 | { | |
1188 | struct maple_alloc *reuse = (struct maple_alloc *)used; | |
1189 | struct maple_alloc *head = mas->alloc; | |
1190 | unsigned long count; | |
1191 | unsigned int requested = mas_alloc_req(mas); | |
1192 | ||
54a611b6 LH |
1193 | count = mas_allocated(mas); |
1194 | ||
541e06b7 LH |
1195 | reuse->request_count = 0; |
1196 | reuse->node_count = 0; | |
1197 | if (count && (head->node_count < MAPLE_ALLOC_SLOTS)) { | |
1198 | head->slot[head->node_count++] = reuse; | |
54a611b6 LH |
1199 | head->total++; |
1200 | goto done; | |
1201 | } | |
1202 | ||
1203 | reuse->total = 1; | |
1204 | if ((head) && !((unsigned long)head & 0x1)) { | |
54a611b6 | 1205 | reuse->slot[0] = head; |
541e06b7 | 1206 | reuse->node_count = 1; |
54a611b6 LH |
1207 | reuse->total += head->total; |
1208 | } | |
1209 | ||
1210 | mas->alloc = reuse; | |
1211 | done: | |
1212 | if (requested > 1) | |
1213 | mas_set_alloc_req(mas, requested - 1); | |
1214 | } | |
1215 | ||
1216 | /* | |
1217 | * mas_alloc_nodes() - Allocate nodes into a maple state | |
1218 | * @mas: The maple state | |
1219 | * @gfp: The GFP Flags | |
1220 | */ | |
1221 | static inline void mas_alloc_nodes(struct ma_state *mas, gfp_t gfp) | |
1222 | { | |
1223 | struct maple_alloc *node; | |
54a611b6 | 1224 | unsigned long allocated = mas_allocated(mas); |
54a611b6 LH |
1225 | unsigned int requested = mas_alloc_req(mas); |
1226 | unsigned int count; | |
1227 | void **slots = NULL; | |
1228 | unsigned int max_req = 0; | |
1229 | ||
1230 | if (!requested) | |
1231 | return; | |
1232 | ||
1233 | mas_set_alloc_req(mas, 0); | |
1234 | if (mas->mas_flags & MA_STATE_PREALLOC) { | |
1235 | if (allocated) | |
1236 | return; | |
067311d3 | 1237 | BUG_ON(!allocated); |
54a611b6 LH |
1238 | WARN_ON(!allocated); |
1239 | } | |
1240 | ||
541e06b7 | 1241 | if (!allocated || mas->alloc->node_count == MAPLE_ALLOC_SLOTS) { |
54a611b6 LH |
1242 | node = (struct maple_alloc *)mt_alloc_one(gfp); |
1243 | if (!node) | |
1244 | goto nomem_one; | |
1245 | ||
541e06b7 | 1246 | if (allocated) { |
54a611b6 | 1247 | node->slot[0] = mas->alloc; |
541e06b7 LH |
1248 | node->node_count = 1; |
1249 | } else { | |
1250 | node->node_count = 0; | |
1251 | } | |
54a611b6 | 1252 | |
54a611b6 | 1253 | mas->alloc = node; |
541e06b7 | 1254 | node->total = ++allocated; |
54a611b6 LH |
1255 | requested--; |
1256 | } | |
1257 | ||
1258 | node = mas->alloc; | |
541e06b7 | 1259 | node->request_count = 0; |
54a611b6 | 1260 | while (requested) { |
1f5f12ec PZ |
1261 | max_req = MAPLE_ALLOC_SLOTS - node->node_count; |
1262 | slots = (void **)&node->slot[node->node_count]; | |
54a611b6 LH |
1263 | max_req = min(requested, max_req); |
1264 | count = mt_alloc_bulk(gfp, max_req, slots); | |
1265 | if (!count) | |
1266 | goto nomem_bulk; | |
1267 | ||
1f5f12ec PZ |
1268 | if (node->node_count == 0) { |
1269 | node->slot[0]->node_count = 0; | |
1270 | node->slot[0]->request_count = 0; | |
1271 | } | |
1272 | ||
54a611b6 | 1273 | node->node_count += count; |
541e06b7 | 1274 | allocated += count; |
c61b3a2b | 1275 | node = node->slot[0]; |
54a611b6 LH |
1276 | requested -= count; |
1277 | } | |
541e06b7 | 1278 | mas->alloc->total = allocated; |
54a611b6 LH |
1279 | return; |
1280 | ||
1281 | nomem_bulk: | |
1282 | /* Clean up potential freed allocations on bulk failure */ | |
1283 | memset(slots, 0, max_req * sizeof(unsigned long)); | |
1284 | nomem_one: | |
1285 | mas_set_alloc_req(mas, requested); | |
1286 | if (mas->alloc && !(((unsigned long)mas->alloc & 0x1))) | |
541e06b7 | 1287 | mas->alloc->total = allocated; |
54a611b6 | 1288 | mas_set_err(mas, -ENOMEM); |
54a611b6 LH |
1289 | } |
1290 | ||
1291 | /* | |
1292 | * mas_free() - Free an encoded maple node | |
1293 | * @mas: The maple state | |
1294 | * @used: The encoded maple node to free. | |
1295 | * | |
1296 | * Uses rcu free if necessary, pushes @used back on the maple state allocations | |
1297 | * otherwise. | |
1298 | */ | |
1299 | static inline void mas_free(struct ma_state *mas, struct maple_enode *used) | |
1300 | { | |
1301 | struct maple_node *tmp = mte_to_node(used); | |
1302 | ||
1303 | if (mt_in_rcu(mas->tree)) | |
1304 | ma_free_rcu(tmp); | |
1305 | else | |
1306 | mas_push_node(mas, tmp); | |
1307 | } | |
1308 | ||
1309 | /* | |
e755c43e SK |
1310 | * mas_node_count_gfp() - Check if enough nodes are allocated and request more |
1311 | * if there is not enough nodes. | |
54a611b6 LH |
1312 | * @mas: The maple state |
1313 | * @count: The number of nodes needed | |
1314 | * @gfp: the gfp flags | |
1315 | */ | |
1316 | static void mas_node_count_gfp(struct ma_state *mas, int count, gfp_t gfp) | |
1317 | { | |
1318 | unsigned long allocated = mas_allocated(mas); | |
1319 | ||
1320 | if (allocated < count) { | |
1321 | mas_set_alloc_req(mas, count - allocated); | |
1322 | mas_alloc_nodes(mas, gfp); | |
1323 | } | |
1324 | } | |
1325 | ||
1326 | /* | |
1327 | * mas_node_count() - Check if enough nodes are allocated and request more if | |
1328 | * there is not enough nodes. | |
1329 | * @mas: The maple state | |
1330 | * @count: The number of nodes needed | |
1331 | * | |
1332 | * Note: Uses GFP_NOWAIT | __GFP_NOWARN for gfp flags. | |
1333 | */ | |
1334 | static void mas_node_count(struct ma_state *mas, int count) | |
1335 | { | |
1336 | return mas_node_count_gfp(mas, count, GFP_NOWAIT | __GFP_NOWARN); | |
1337 | } | |
1338 | ||
1339 | /* | |
1340 | * mas_start() - Sets up maple state for operations. | |
1341 | * @mas: The maple state. | |
1342 | * | |
067311d3 | 1343 | * If mas->status == mas_start, then set the min, max and depth to |
54a611b6 LH |
1344 | * defaults. |
1345 | * | |
1346 | * Return: | |
067311d3 LH |
1347 | * - If mas->node is an error or not mas_start, return NULL. |
1348 | * - If it's an empty tree: NULL & mas->status == ma_none | |
1349 | * - If it's a single entry: The entry & mas->status == mas_root | |
1350 | * - If it's a tree: NULL & mas->status == safe root node. | |
54a611b6 LH |
1351 | */ |
1352 | static inline struct maple_enode *mas_start(struct ma_state *mas) | |
1353 | { | |
1354 | if (likely(mas_is_start(mas))) { | |
1355 | struct maple_enode *root; | |
1356 | ||
54a611b6 LH |
1357 | mas->min = 0; |
1358 | mas->max = ULONG_MAX; | |
54a611b6 | 1359 | |
a7b92d59 | 1360 | retry: |
d0411860 | 1361 | mas->depth = 0; |
54a611b6 LH |
1362 | root = mas_root(mas); |
1363 | /* Tree with nodes */ | |
1364 | if (likely(xa_is_node(root))) { | |
9bbba563 | 1365 | mas->depth = 1; |
067311d3 | 1366 | mas->status = ma_active; |
54a611b6 | 1367 | mas->node = mte_safe_root(root); |
46b34584 | 1368 | mas->offset = 0; |
a7b92d59 LH |
1369 | if (mte_dead_node(mas->node)) |
1370 | goto retry; | |
1371 | ||
54a611b6 LH |
1372 | return NULL; |
1373 | } | |
1374 | ||
1375 | /* empty tree */ | |
1376 | if (unlikely(!root)) { | |
067311d3 LH |
1377 | mas->node = NULL; |
1378 | mas->status = ma_none; | |
54a611b6 LH |
1379 | mas->offset = MAPLE_NODE_SLOTS; |
1380 | return NULL; | |
1381 | } | |
1382 | ||
1383 | /* Single entry tree */ | |
067311d3 | 1384 | mas->status = ma_root; |
54a611b6 LH |
1385 | mas->offset = MAPLE_NODE_SLOTS; |
1386 | ||
1387 | /* Single entry tree. */ | |
1388 | if (mas->index > 0) | |
1389 | return NULL; | |
1390 | ||
1391 | return root; | |
1392 | } | |
1393 | ||
1394 | return NULL; | |
1395 | } | |
1396 | ||
1397 | /* | |
1398 | * ma_data_end() - Find the end of the data in a node. | |
1399 | * @node: The maple node | |
1400 | * @type: The maple node type | |
1401 | * @pivots: The array of pivots in the node | |
1402 | * @max: The maximum value in the node | |
1403 | * | |
1404 | * Uses metadata to find the end of the data when possible. | |
1405 | * Return: The zero indexed last slot with data (may be null). | |
1406 | */ | |
271f61a8 LH |
1407 | static __always_inline unsigned char ma_data_end(struct maple_node *node, |
1408 | enum maple_type type, unsigned long *pivots, unsigned long max) | |
54a611b6 LH |
1409 | { |
1410 | unsigned char offset; | |
1411 | ||
39d0bd86 LH |
1412 | if (!pivots) |
1413 | return 0; | |
1414 | ||
54a611b6 LH |
1415 | if (type == maple_arange_64) |
1416 | return ma_meta_end(node, type); | |
1417 | ||
1418 | offset = mt_pivots[type] - 1; | |
1419 | if (likely(!pivots[offset])) | |
1420 | return ma_meta_end(node, type); | |
1421 | ||
1422 | if (likely(pivots[offset] == max)) | |
1423 | return offset; | |
1424 | ||
1425 | return mt_pivots[type]; | |
1426 | } | |
1427 | ||
1428 | /* | |
1429 | * mas_data_end() - Find the end of the data (slot). | |
1430 | * @mas: the maple state | |
1431 | * | |
1432 | * This method is optimized to check the metadata of a node if the node type | |
1433 | * supports data end metadata. | |
1434 | * | |
1435 | * Return: The zero indexed last slot with data (may be null). | |
1436 | */ | |
1437 | static inline unsigned char mas_data_end(struct ma_state *mas) | |
1438 | { | |
1439 | enum maple_type type; | |
1440 | struct maple_node *node; | |
1441 | unsigned char offset; | |
1442 | unsigned long *pivots; | |
1443 | ||
1444 | type = mte_node_type(mas->node); | |
1445 | node = mas_mn(mas); | |
1446 | if (type == maple_arange_64) | |
1447 | return ma_meta_end(node, type); | |
1448 | ||
1449 | pivots = ma_pivots(node, type); | |
39d0bd86 LH |
1450 | if (unlikely(ma_dead_node(node))) |
1451 | return 0; | |
1452 | ||
54a611b6 LH |
1453 | offset = mt_pivots[type] - 1; |
1454 | if (likely(!pivots[offset])) | |
1455 | return ma_meta_end(node, type); | |
1456 | ||
1457 | if (likely(pivots[offset] == mas->max)) | |
1458 | return offset; | |
1459 | ||
1460 | return mt_pivots[type]; | |
1461 | } | |
1462 | ||
1463 | /* | |
1464 | * mas_leaf_max_gap() - Returns the largest gap in a leaf node | |
1465 | * @mas - the maple state | |
1466 | * | |
1467 | * Return: The maximum gap in the leaf. | |
1468 | */ | |
1469 | static unsigned long mas_leaf_max_gap(struct ma_state *mas) | |
1470 | { | |
1471 | enum maple_type mt; | |
1472 | unsigned long pstart, gap, max_gap; | |
1473 | struct maple_node *mn; | |
1474 | unsigned long *pivots; | |
1475 | void __rcu **slots; | |
1476 | unsigned char i; | |
1477 | unsigned char max_piv; | |
1478 | ||
1479 | mt = mte_node_type(mas->node); | |
1480 | mn = mas_mn(mas); | |
1481 | slots = ma_slots(mn, mt); | |
1482 | max_gap = 0; | |
1483 | if (unlikely(ma_is_dense(mt))) { | |
1484 | gap = 0; | |
1485 | for (i = 0; i < mt_slots[mt]; i++) { | |
1486 | if (slots[i]) { | |
1487 | if (gap > max_gap) | |
1488 | max_gap = gap; | |
1489 | gap = 0; | |
1490 | } else { | |
1491 | gap++; | |
1492 | } | |
1493 | } | |
1494 | if (gap > max_gap) | |
1495 | max_gap = gap; | |
1496 | return max_gap; | |
1497 | } | |
1498 | ||
1499 | /* | |
1500 | * Check the first implied pivot optimizes the loop below and slot 1 may | |
1501 | * be skipped if there is a gap in slot 0. | |
1502 | */ | |
1503 | pivots = ma_pivots(mn, mt); | |
1504 | if (likely(!slots[0])) { | |
1505 | max_gap = pivots[0] - mas->min + 1; | |
1506 | i = 2; | |
1507 | } else { | |
1508 | i = 1; | |
1509 | } | |
1510 | ||
1511 | /* reduce max_piv as the special case is checked before the loop */ | |
1512 | max_piv = ma_data_end(mn, mt, pivots, mas->max) - 1; | |
1513 | /* | |
1514 | * Check end implied pivot which can only be a gap on the right most | |
1515 | * node. | |
1516 | */ | |
1517 | if (unlikely(mas->max == ULONG_MAX) && !slots[max_piv + 1]) { | |
1518 | gap = ULONG_MAX - pivots[max_piv]; | |
1519 | if (gap > max_gap) | |
1520 | max_gap = gap; | |
7e552dcd PZ |
1521 | |
1522 | if (max_gap > pivots[max_piv] - mas->min) | |
1523 | return max_gap; | |
54a611b6 LH |
1524 | } |
1525 | ||
1526 | for (; i <= max_piv; i++) { | |
1527 | /* data == no gap. */ | |
1528 | if (likely(slots[i])) | |
1529 | continue; | |
1530 | ||
1531 | pstart = pivots[i - 1]; | |
1532 | gap = pivots[i] - pstart; | |
1533 | if (gap > max_gap) | |
1534 | max_gap = gap; | |
1535 | ||
1536 | /* There cannot be two gaps in a row. */ | |
1537 | i++; | |
1538 | } | |
1539 | return max_gap; | |
1540 | } | |
1541 | ||
1542 | /* | |
1543 | * ma_max_gap() - Get the maximum gap in a maple node (non-leaf) | |
1544 | * @node: The maple node | |
1545 | * @gaps: The pointer to the gaps | |
1546 | * @mt: The maple node type | |
1547 | * @*off: Pointer to store the offset location of the gap. | |
1548 | * | |
1549 | * Uses the metadata data end to scan backwards across set gaps. | |
1550 | * | |
1551 | * Return: The maximum gap value | |
1552 | */ | |
1553 | static inline unsigned long | |
1554 | ma_max_gap(struct maple_node *node, unsigned long *gaps, enum maple_type mt, | |
1555 | unsigned char *off) | |
1556 | { | |
1557 | unsigned char offset, i; | |
1558 | unsigned long max_gap = 0; | |
1559 | ||
1560 | i = offset = ma_meta_end(node, mt); | |
1561 | do { | |
1562 | if (gaps[i] > max_gap) { | |
1563 | max_gap = gaps[i]; | |
1564 | offset = i; | |
1565 | } | |
1566 | } while (i--); | |
1567 | ||
1568 | *off = offset; | |
1569 | return max_gap; | |
1570 | } | |
1571 | ||
1572 | /* | |
1573 | * mas_max_gap() - find the largest gap in a non-leaf node and set the slot. | |
1574 | * @mas: The maple state. | |
1575 | * | |
54a611b6 LH |
1576 | * Return: The gap value. |
1577 | */ | |
1578 | static inline unsigned long mas_max_gap(struct ma_state *mas) | |
1579 | { | |
1580 | unsigned long *gaps; | |
1581 | unsigned char offset; | |
1582 | enum maple_type mt; | |
1583 | struct maple_node *node; | |
1584 | ||
1585 | mt = mte_node_type(mas->node); | |
1586 | if (ma_is_leaf(mt)) | |
1587 | return mas_leaf_max_gap(mas); | |
1588 | ||
1589 | node = mas_mn(mas); | |
bec1b51e | 1590 | MAS_BUG_ON(mas, mt != maple_arange_64); |
c5e94121 | 1591 | offset = ma_meta_gap(node); |
54a611b6 LH |
1592 | gaps = ma_gaps(node, mt); |
1593 | return gaps[offset]; | |
1594 | } | |
1595 | ||
1596 | /* | |
1597 | * mas_parent_gap() - Set the parent gap and any gaps above, as needed | |
1598 | * @mas: The maple state | |
1599 | * @offset: The gap offset in the parent to set | |
1600 | * @new: The new gap value. | |
1601 | * | |
1602 | * Set the parent gap then continue to set the gap upwards, using the metadata | |
1603 | * of the parent to see if it is necessary to check the node above. | |
1604 | */ | |
1605 | static inline void mas_parent_gap(struct ma_state *mas, unsigned char offset, | |
1606 | unsigned long new) | |
1607 | { | |
1608 | unsigned long meta_gap = 0; | |
1609 | struct maple_node *pnode; | |
1610 | struct maple_enode *penode; | |
1611 | unsigned long *pgaps; | |
1612 | unsigned char meta_offset; | |
1613 | enum maple_type pmt; | |
1614 | ||
1615 | pnode = mte_parent(mas->node); | |
afc754c6 | 1616 | pmt = mas_parent_type(mas, mas->node); |
54a611b6 LH |
1617 | penode = mt_mk_node(pnode, pmt); |
1618 | pgaps = ma_gaps(pnode, pmt); | |
1619 | ||
1620 | ascend: | |
bec1b51e | 1621 | MAS_BUG_ON(mas, pmt != maple_arange_64); |
c5e94121 | 1622 | meta_offset = ma_meta_gap(pnode); |
d695c30a | 1623 | meta_gap = pgaps[meta_offset]; |
54a611b6 LH |
1624 | |
1625 | pgaps[offset] = new; | |
1626 | ||
1627 | if (meta_gap == new) | |
1628 | return; | |
1629 | ||
1630 | if (offset != meta_offset) { | |
1631 | if (meta_gap > new) | |
1632 | return; | |
1633 | ||
1634 | ma_set_meta_gap(pnode, pmt, offset); | |
1635 | } else if (new < meta_gap) { | |
54a611b6 LH |
1636 | new = ma_max_gap(pnode, pgaps, pmt, &meta_offset); |
1637 | ma_set_meta_gap(pnode, pmt, meta_offset); | |
1638 | } | |
1639 | ||
1640 | if (ma_is_root(pnode)) | |
1641 | return; | |
1642 | ||
1643 | /* Go to the parent node. */ | |
1644 | pnode = mte_parent(penode); | |
afc754c6 | 1645 | pmt = mas_parent_type(mas, penode); |
54a611b6 LH |
1646 | pgaps = ma_gaps(pnode, pmt); |
1647 | offset = mte_parent_slot(penode); | |
1648 | penode = mt_mk_node(pnode, pmt); | |
1649 | goto ascend; | |
1650 | } | |
1651 | ||
1652 | /* | |
1653 | * mas_update_gap() - Update a nodes gaps and propagate up if necessary. | |
1654 | * @mas - the maple state. | |
1655 | */ | |
1656 | static inline void mas_update_gap(struct ma_state *mas) | |
1657 | { | |
1658 | unsigned char pslot; | |
1659 | unsigned long p_gap; | |
1660 | unsigned long max_gap; | |
1661 | ||
1662 | if (!mt_is_alloc(mas->tree)) | |
1663 | return; | |
1664 | ||
1665 | if (mte_is_root(mas->node)) | |
1666 | return; | |
1667 | ||
1668 | max_gap = mas_max_gap(mas); | |
1669 | ||
1670 | pslot = mte_parent_slot(mas->node); | |
1671 | p_gap = ma_gaps(mte_parent(mas->node), | |
afc754c6 | 1672 | mas_parent_type(mas, mas->node))[pslot]; |
54a611b6 LH |
1673 | |
1674 | if (p_gap != max_gap) | |
1675 | mas_parent_gap(mas, pslot, max_gap); | |
1676 | } | |
1677 | ||
1678 | /* | |
1679 | * mas_adopt_children() - Set the parent pointer of all nodes in @parent to | |
1680 | * @parent with the slot encoded. | |
1681 | * @mas - the maple state (for the tree) | |
1682 | * @parent - the maple encoded node containing the children. | |
1683 | */ | |
1684 | static inline void mas_adopt_children(struct ma_state *mas, | |
1685 | struct maple_enode *parent) | |
1686 | { | |
1687 | enum maple_type type = mte_node_type(parent); | |
068bafca | 1688 | struct maple_node *node = mte_to_node(parent); |
54a611b6 LH |
1689 | void __rcu **slots = ma_slots(node, type); |
1690 | unsigned long *pivots = ma_pivots(node, type); | |
1691 | struct maple_enode *child; | |
1692 | unsigned char offset; | |
1693 | ||
1694 | offset = ma_data_end(node, type, pivots, mas->max); | |
1695 | do { | |
1696 | child = mas_slot_locked(mas, slots, offset); | |
bf96715e | 1697 | mas_set_parent(mas, child, parent, offset); |
54a611b6 LH |
1698 | } while (offset--); |
1699 | } | |
1700 | ||
1701 | /* | |
1238f6a2 LH |
1702 | * mas_put_in_tree() - Put a new node in the tree, smp_wmb(), and mark the old |
1703 | * node as dead. | |
1704 | * @mas - the maple state with the new node | |
1705 | * @old_enode - The old maple encoded node to replace. | |
54a611b6 | 1706 | */ |
1238f6a2 LH |
1707 | static inline void mas_put_in_tree(struct ma_state *mas, |
1708 | struct maple_enode *old_enode) | |
14c4b5ab | 1709 | __must_hold(mas->tree->ma_lock) |
54a611b6 | 1710 | { |
1238f6a2 LH |
1711 | unsigned char offset; |
1712 | void __rcu **slots; | |
54a611b6 LH |
1713 | |
1714 | if (mte_is_root(mas->node)) { | |
4ffc2ee2 | 1715 | mas_mn(mas)->parent = ma_parent_ptr(mas_tree_parent(mas)); |
54a611b6 LH |
1716 | rcu_assign_pointer(mas->tree->ma_root, mte_mk_root(mas->node)); |
1717 | mas_set_height(mas); | |
1718 | } else { | |
1238f6a2 LH |
1719 | |
1720 | offset = mte_parent_slot(mas->node); | |
1721 | slots = ma_slots(mte_parent(mas->node), | |
1722 | mas_parent_type(mas, mas->node)); | |
54a611b6 LH |
1723 | rcu_assign_pointer(slots[offset], mas->node); |
1724 | } | |
1725 | ||
1238f6a2 | 1726 | mte_set_node_dead(old_enode); |
54a611b6 LH |
1727 | } |
1728 | ||
72bcf4aa LH |
1729 | /* |
1730 | * mas_replace_node() - Replace a node by putting it in the tree, marking it | |
1731 | * dead, and freeing it. | |
1732 | * the parent encoding to locate the maple node in the tree. | |
1733 | * @mas - the ma_state with @mas->node pointing to the new node. | |
1734 | * @old_enode - The old maple encoded node. | |
1735 | */ | |
1736 | static inline void mas_replace_node(struct ma_state *mas, | |
1737 | struct maple_enode *old_enode) | |
1738 | __must_hold(mas->tree->ma_lock) | |
1739 | { | |
1238f6a2 | 1740 | mas_put_in_tree(mas, old_enode); |
72bcf4aa LH |
1741 | mas_free(mas, old_enode); |
1742 | } | |
1743 | ||
54a611b6 | 1744 | /* |
530f745c LH |
1745 | * mas_find_child() - Find a child who has the parent @mas->node. |
1746 | * @mas: the maple state with the parent. | |
54a611b6 LH |
1747 | * @child: the maple state to store the child. |
1748 | */ | |
530f745c | 1749 | static inline bool mas_find_child(struct ma_state *mas, struct ma_state *child) |
14c4b5ab | 1750 | __must_hold(mas->tree->ma_lock) |
54a611b6 LH |
1751 | { |
1752 | enum maple_type mt; | |
1753 | unsigned char offset; | |
1754 | unsigned char end; | |
1755 | unsigned long *pivots; | |
1756 | struct maple_enode *entry; | |
1757 | struct maple_node *node; | |
1758 | void __rcu **slots; | |
1759 | ||
1760 | mt = mte_node_type(mas->node); | |
1761 | node = mas_mn(mas); | |
1762 | slots = ma_slots(node, mt); | |
1763 | pivots = ma_pivots(node, mt); | |
1764 | end = ma_data_end(node, mt, pivots, mas->max); | |
1765 | for (offset = mas->offset; offset <= end; offset++) { | |
1766 | entry = mas_slot_locked(mas, slots, offset); | |
1767 | if (mte_parent(entry) == node) { | |
1768 | *child = *mas; | |
1769 | mas->offset = offset + 1; | |
1770 | child->offset = offset; | |
1771 | mas_descend(child); | |
1772 | child->offset = 0; | |
1773 | return true; | |
1774 | } | |
1775 | } | |
1776 | return false; | |
1777 | } | |
1778 | ||
1779 | /* | |
1780 | * mab_shift_right() - Shift the data in mab right. Note, does not clean out the | |
1781 | * old data or set b_node->b_end. | |
1782 | * @b_node: the maple_big_node | |
1783 | * @shift: the shift count | |
1784 | */ | |
1785 | static inline void mab_shift_right(struct maple_big_node *b_node, | |
1786 | unsigned char shift) | |
1787 | { | |
1788 | unsigned long size = b_node->b_end * sizeof(unsigned long); | |
1789 | ||
1790 | memmove(b_node->pivot + shift, b_node->pivot, size); | |
1791 | memmove(b_node->slot + shift, b_node->slot, size); | |
1792 | if (b_node->type == maple_arange_64) | |
1793 | memmove(b_node->gap + shift, b_node->gap, size); | |
1794 | } | |
1795 | ||
1796 | /* | |
1797 | * mab_middle_node() - Check if a middle node is needed (unlikely) | |
1798 | * @b_node: the maple_big_node that contains the data. | |
1799 | * @size: the amount of data in the b_node | |
1800 | * @split: the potential split location | |
1801 | * @slot_count: the size that can be stored in a single node being considered. | |
1802 | * | |
1803 | * Return: true if a middle node is required. | |
1804 | */ | |
1805 | static inline bool mab_middle_node(struct maple_big_node *b_node, int split, | |
1806 | unsigned char slot_count) | |
1807 | { | |
1808 | unsigned char size = b_node->b_end; | |
1809 | ||
1810 | if (size >= 2 * slot_count) | |
1811 | return true; | |
1812 | ||
1813 | if (!b_node->slot[split] && (size >= 2 * slot_count - 1)) | |
1814 | return true; | |
1815 | ||
1816 | return false; | |
1817 | } | |
1818 | ||
1819 | /* | |
1820 | * mab_no_null_split() - ensure the split doesn't fall on a NULL | |
1821 | * @b_node: the maple_big_node with the data | |
1822 | * @split: the suggested split location | |
1823 | * @slot_count: the number of slots in the node being considered. | |
1824 | * | |
1825 | * Return: the split location. | |
1826 | */ | |
1827 | static inline int mab_no_null_split(struct maple_big_node *b_node, | |
1828 | unsigned char split, unsigned char slot_count) | |
1829 | { | |
1830 | if (!b_node->slot[split]) { | |
1831 | /* | |
1832 | * If the split is less than the max slot && the right side will | |
1833 | * still be sufficient, then increment the split on NULL. | |
1834 | */ | |
1835 | if ((split < slot_count - 1) && | |
1836 | (b_node->b_end - split) > (mt_min_slots[b_node->type])) | |
1837 | split++; | |
1838 | else | |
1839 | split--; | |
1840 | } | |
1841 | return split; | |
1842 | } | |
1843 | ||
1844 | /* | |
1845 | * mab_calc_split() - Calculate the split location and if there needs to be two | |
1846 | * splits. | |
1847 | * @bn: The maple_big_node with the data | |
1848 | * @mid_split: The second split, if required. 0 otherwise. | |
1849 | * | |
1850 | * Return: The first split location. The middle split is set in @mid_split. | |
1851 | */ | |
1852 | static inline int mab_calc_split(struct ma_state *mas, | |
1853 | struct maple_big_node *bn, unsigned char *mid_split, unsigned long min) | |
1854 | { | |
1855 | unsigned char b_end = bn->b_end; | |
1856 | int split = b_end / 2; /* Assume equal split. */ | |
1857 | unsigned char slot_min, slot_count = mt_slots[bn->type]; | |
1858 | ||
1859 | /* | |
1860 | * To support gap tracking, all NULL entries are kept together and a node cannot | |
1861 | * end on a NULL entry, with the exception of the left-most leaf. The | |
1862 | * limitation means that the split of a node must be checked for this condition | |
1863 | * and be able to put more data in one direction or the other. | |
1864 | */ | |
1865 | if (unlikely((mas->mas_flags & MA_STATE_BULK))) { | |
1866 | *mid_split = 0; | |
1867 | split = b_end - mt_min_slots[bn->type]; | |
1868 | ||
1869 | if (!ma_is_leaf(bn->type)) | |
1870 | return split; | |
1871 | ||
1872 | mas->mas_flags |= MA_STATE_REBALANCE; | |
1873 | if (!bn->slot[split]) | |
1874 | split--; | |
1875 | return split; | |
1876 | } | |
1877 | ||
1878 | /* | |
1879 | * Although extremely rare, it is possible to enter what is known as the 3-way | |
1880 | * split scenario. The 3-way split comes about by means of a store of a range | |
1881 | * that overwrites the end and beginning of two full nodes. The result is a set | |
1882 | * of entries that cannot be stored in 2 nodes. Sometimes, these two nodes can | |
1883 | * also be located in different parent nodes which are also full. This can | |
1884 | * carry upwards all the way to the root in the worst case. | |
1885 | */ | |
1886 | if (unlikely(mab_middle_node(bn, split, slot_count))) { | |
1887 | split = b_end / 3; | |
1888 | *mid_split = split * 2; | |
1889 | } else { | |
1890 | slot_min = mt_min_slots[bn->type]; | |
1891 | ||
1892 | *mid_split = 0; | |
1893 | /* | |
1894 | * Avoid having a range less than the slot count unless it | |
1895 | * causes one node to be deficient. | |
1896 | * NOTE: mt_min_slots is 1 based, b_end and split are zero. | |
1897 | */ | |
5729e06c LH |
1898 | while ((split < slot_count - 1) && |
1899 | ((bn->pivot[split] - min) < slot_count - 1) && | |
1900 | (b_end - split > slot_min)) | |
54a611b6 LH |
1901 | split++; |
1902 | } | |
1903 | ||
1904 | /* Avoid ending a node on a NULL entry */ | |
1905 | split = mab_no_null_split(bn, split, slot_count); | |
54a611b6 | 1906 | |
e11cb683 VY |
1907 | if (unlikely(*mid_split)) |
1908 | *mid_split = mab_no_null_split(bn, *mid_split, slot_count); | |
54a611b6 LH |
1909 | |
1910 | return split; | |
1911 | } | |
1912 | ||
1913 | /* | |
1914 | * mas_mab_cp() - Copy data from a maple state inclusively to a maple_big_node | |
1915 | * and set @b_node->b_end to the next free slot. | |
1916 | * @mas: The maple state | |
1917 | * @mas_start: The starting slot to copy | |
1918 | * @mas_end: The end slot to copy (inclusively) | |
1919 | * @b_node: The maple_big_node to place the data | |
1920 | * @mab_start: The starting location in maple_big_node to store the data. | |
1921 | */ | |
1922 | static inline void mas_mab_cp(struct ma_state *mas, unsigned char mas_start, | |
1923 | unsigned char mas_end, struct maple_big_node *b_node, | |
1924 | unsigned char mab_start) | |
1925 | { | |
1926 | enum maple_type mt; | |
1927 | struct maple_node *node; | |
1928 | void __rcu **slots; | |
1929 | unsigned long *pivots, *gaps; | |
1930 | int i = mas_start, j = mab_start; | |
1931 | unsigned char piv_end; | |
1932 | ||
1933 | node = mas_mn(mas); | |
1934 | mt = mte_node_type(mas->node); | |
1935 | pivots = ma_pivots(node, mt); | |
1936 | if (!i) { | |
1937 | b_node->pivot[j] = pivots[i++]; | |
1938 | if (unlikely(i > mas_end)) | |
1939 | goto complete; | |
1940 | j++; | |
1941 | } | |
1942 | ||
1943 | piv_end = min(mas_end, mt_pivots[mt]); | |
1944 | for (; i < piv_end; i++, j++) { | |
1945 | b_node->pivot[j] = pivots[i]; | |
1946 | if (unlikely(!b_node->pivot[j])) | |
1947 | break; | |
1948 | ||
1949 | if (unlikely(mas->max == b_node->pivot[j])) | |
1950 | goto complete; | |
1951 | } | |
1952 | ||
1953 | if (likely(i <= mas_end)) | |
1954 | b_node->pivot[j] = mas_safe_pivot(mas, pivots, i, mt); | |
1955 | ||
1956 | complete: | |
1957 | b_node->b_end = ++j; | |
1958 | j -= mab_start; | |
1959 | slots = ma_slots(node, mt); | |
1960 | memcpy(b_node->slot + mab_start, slots + mas_start, sizeof(void *) * j); | |
1961 | if (!ma_is_leaf(mt) && mt_is_alloc(mas->tree)) { | |
1962 | gaps = ma_gaps(node, mt); | |
1963 | memcpy(b_node->gap + mab_start, gaps + mas_start, | |
1964 | sizeof(unsigned long) * j); | |
1965 | } | |
1966 | } | |
1967 | ||
1968 | /* | |
1969 | * mas_leaf_set_meta() - Set the metadata of a leaf if possible. | |
54a611b6 | 1970 | * @node: The maple node |
54a611b6 | 1971 | * @mt: The maple type |
330018fe | 1972 | * @end: The node end |
54a611b6 | 1973 | */ |
330018fe | 1974 | static inline void mas_leaf_set_meta(struct maple_node *node, |
54a611b6 LH |
1975 | enum maple_type mt, unsigned char end) |
1976 | { | |
54a611b6 LH |
1977 | if (end < mt_slots[mt] - 1) |
1978 | ma_set_meta(node, mt, 0, end); | |
1979 | } | |
1980 | ||
1981 | /* | |
1982 | * mab_mas_cp() - Copy data from maple_big_node to a maple encoded node. | |
1983 | * @b_node: the maple_big_node that has the data | |
1984 | * @mab_start: the start location in @b_node. | |
1985 | * @mab_end: The end location in @b_node (inclusively) | |
1986 | * @mas: The maple state with the maple encoded node. | |
1987 | */ | |
1988 | static inline void mab_mas_cp(struct maple_big_node *b_node, | |
1989 | unsigned char mab_start, unsigned char mab_end, | |
1990 | struct ma_state *mas, bool new_max) | |
1991 | { | |
1992 | int i, j = 0; | |
1993 | enum maple_type mt = mte_node_type(mas->node); | |
1994 | struct maple_node *node = mte_to_node(mas->node); | |
1995 | void __rcu **slots = ma_slots(node, mt); | |
1996 | unsigned long *pivots = ma_pivots(node, mt); | |
1997 | unsigned long *gaps = NULL; | |
1998 | unsigned char end; | |
1999 | ||
2000 | if (mab_end - mab_start > mt_pivots[mt]) | |
2001 | mab_end--; | |
2002 | ||
2003 | if (!pivots[mt_pivots[mt] - 1]) | |
2004 | slots[mt_pivots[mt]] = NULL; | |
2005 | ||
2006 | i = mab_start; | |
2007 | do { | |
2008 | pivots[j++] = b_node->pivot[i++]; | |
2009 | } while (i <= mab_end && likely(b_node->pivot[i])); | |
2010 | ||
2011 | memcpy(slots, b_node->slot + mab_start, | |
2012 | sizeof(void *) * (i - mab_start)); | |
2013 | ||
2014 | if (new_max) | |
2015 | mas->max = b_node->pivot[i - 1]; | |
2016 | ||
2017 | end = j - 1; | |
2018 | if (likely(!ma_is_leaf(mt) && mt_is_alloc(mas->tree))) { | |
2019 | unsigned long max_gap = 0; | |
d695c30a | 2020 | unsigned char offset = 0; |
54a611b6 LH |
2021 | |
2022 | gaps = ma_gaps(node, mt); | |
2023 | do { | |
2024 | gaps[--j] = b_node->gap[--i]; | |
2025 | if (gaps[j] > max_gap) { | |
2026 | offset = j; | |
2027 | max_gap = gaps[j]; | |
2028 | } | |
2029 | } while (j); | |
2030 | ||
2031 | ma_set_meta(node, mt, offset, end); | |
2032 | } else { | |
330018fe | 2033 | mas_leaf_set_meta(node, mt, end); |
54a611b6 LH |
2034 | } |
2035 | } | |
2036 | ||
54a611b6 LH |
2037 | /* |
2038 | * mas_bulk_rebalance() - Rebalance the end of a tree after a bulk insert. | |
2039 | * @mas: The maple state | |
2040 | * @end: The maple node end | |
2041 | * @mt: The maple node type | |
2042 | */ | |
2043 | static inline void mas_bulk_rebalance(struct ma_state *mas, unsigned char end, | |
2044 | enum maple_type mt) | |
2045 | { | |
2046 | if (!(mas->mas_flags & MA_STATE_BULK)) | |
2047 | return; | |
2048 | ||
2049 | if (mte_is_root(mas->node)) | |
2050 | return; | |
2051 | ||
2052 | if (end > mt_min_slots[mt]) { | |
2053 | mas->mas_flags &= ~MA_STATE_REBALANCE; | |
2054 | return; | |
2055 | } | |
2056 | } | |
2057 | ||
2058 | /* | |
2059 | * mas_store_b_node() - Store an @entry into the b_node while also copying the | |
2060 | * data from a maple encoded node. | |
2061 | * @wr_mas: the maple write state | |
2062 | * @b_node: the maple_big_node to fill with data | |
2063 | * @offset_end: the offset to end copying | |
2064 | * | |
2065 | * Return: The actual end of the data stored in @b_node | |
2066 | */ | |
44081c77 | 2067 | static noinline_for_kasan void mas_store_b_node(struct ma_wr_state *wr_mas, |
54a611b6 LH |
2068 | struct maple_big_node *b_node, unsigned char offset_end) |
2069 | { | |
2070 | unsigned char slot; | |
2071 | unsigned char b_end; | |
2072 | /* Possible underflow of piv will wrap back to 0 before use. */ | |
2073 | unsigned long piv; | |
2074 | struct ma_state *mas = wr_mas->mas; | |
2075 | ||
2076 | b_node->type = wr_mas->type; | |
2077 | b_end = 0; | |
2078 | slot = mas->offset; | |
2079 | if (slot) { | |
2080 | /* Copy start data up to insert. */ | |
2081 | mas_mab_cp(mas, 0, slot - 1, b_node, 0); | |
2082 | b_end = b_node->b_end; | |
2083 | piv = b_node->pivot[b_end - 1]; | |
2084 | } else | |
2085 | piv = mas->min - 1; | |
2086 | ||
2087 | if (piv + 1 < mas->index) { | |
2088 | /* Handle range starting after old range */ | |
2089 | b_node->slot[b_end] = wr_mas->content; | |
2090 | if (!wr_mas->content) | |
2091 | b_node->gap[b_end] = mas->index - 1 - piv; | |
2092 | b_node->pivot[b_end++] = mas->index - 1; | |
2093 | } | |
2094 | ||
2095 | /* Store the new entry. */ | |
2096 | mas->offset = b_end; | |
2097 | b_node->slot[b_end] = wr_mas->entry; | |
2098 | b_node->pivot[b_end] = mas->last; | |
2099 | ||
2100 | /* Appended. */ | |
2101 | if (mas->last >= mas->max) | |
2102 | goto b_end; | |
2103 | ||
2104 | /* Handle new range ending before old range ends */ | |
29b2681f | 2105 | piv = mas_safe_pivot(mas, wr_mas->pivots, offset_end, wr_mas->type); |
54a611b6 LH |
2106 | if (piv > mas->last) { |
2107 | if (piv == ULONG_MAX) | |
2108 | mas_bulk_rebalance(mas, b_node->b_end, wr_mas->type); | |
2109 | ||
2110 | if (offset_end != slot) | |
2111 | wr_mas->content = mas_slot_locked(mas, wr_mas->slots, | |
2112 | offset_end); | |
2113 | ||
2114 | b_node->slot[++b_end] = wr_mas->content; | |
2115 | if (!wr_mas->content) | |
2116 | b_node->gap[b_end] = piv - mas->last + 1; | |
2117 | b_node->pivot[b_end] = piv; | |
2118 | } | |
2119 | ||
2120 | slot = offset_end + 1; | |
0de56e38 | 2121 | if (slot > mas->end) |
54a611b6 LH |
2122 | goto b_end; |
2123 | ||
2124 | /* Copy end data to the end of the node. */ | |
0de56e38 | 2125 | mas_mab_cp(mas, slot, mas->end + 1, b_node, ++b_end); |
54a611b6 LH |
2126 | b_node->b_end--; |
2127 | return; | |
2128 | ||
2129 | b_end: | |
2130 | b_node->b_end = b_end; | |
2131 | } | |
2132 | ||
2133 | /* | |
2134 | * mas_prev_sibling() - Find the previous node with the same parent. | |
2135 | * @mas: the maple state | |
2136 | * | |
2137 | * Return: True if there is a previous sibling, false otherwise. | |
2138 | */ | |
2139 | static inline bool mas_prev_sibling(struct ma_state *mas) | |
2140 | { | |
2141 | unsigned int p_slot = mte_parent_slot(mas->node); | |
2142 | ||
2143 | if (mte_is_root(mas->node)) | |
2144 | return false; | |
2145 | ||
2146 | if (!p_slot) | |
2147 | return false; | |
2148 | ||
2149 | mas_ascend(mas); | |
2150 | mas->offset = p_slot - 1; | |
2151 | mas_descend(mas); | |
2152 | return true; | |
2153 | } | |
2154 | ||
2155 | /* | |
2156 | * mas_next_sibling() - Find the next node with the same parent. | |
2157 | * @mas: the maple state | |
2158 | * | |
2159 | * Return: true if there is a next sibling, false otherwise. | |
2160 | */ | |
2161 | static inline bool mas_next_sibling(struct ma_state *mas) | |
2162 | { | |
2163 | MA_STATE(parent, mas->tree, mas->index, mas->last); | |
2164 | ||
2165 | if (mte_is_root(mas->node)) | |
2166 | return false; | |
2167 | ||
2168 | parent = *mas; | |
2169 | mas_ascend(&parent); | |
2170 | parent.offset = mte_parent_slot(mas->node) + 1; | |
2171 | if (parent.offset > mas_data_end(&parent)) | |
2172 | return false; | |
2173 | ||
2174 | *mas = parent; | |
2175 | mas_descend(mas); | |
2176 | return true; | |
2177 | } | |
2178 | ||
2179 | /* | |
067311d3 | 2180 | * mte_node_or_none() - Set the enode and state. |
54a611b6 LH |
2181 | * @enode: The encoded maple node. |
2182 | * | |
067311d3 | 2183 | * Set the node to the enode and the status. |
54a611b6 | 2184 | */ |
067311d3 LH |
2185 | static inline void mas_node_or_none(struct ma_state *mas, |
2186 | struct maple_enode *enode) | |
54a611b6 | 2187 | { |
067311d3 LH |
2188 | if (enode) { |
2189 | mas->node = enode; | |
2190 | mas->status = ma_active; | |
2191 | } else { | |
2192 | mas->node = NULL; | |
2193 | mas->status = ma_none; | |
2194 | } | |
54a611b6 LH |
2195 | } |
2196 | ||
2197 | /* | |
2198 | * mas_wr_node_walk() - Find the correct offset for the index in the @mas. | |
2199 | * @wr_mas: The maple write state | |
2200 | * | |
2201 | * Uses mas_slot_locked() and does not need to worry about dead nodes. | |
2202 | */ | |
2203 | static inline void mas_wr_node_walk(struct ma_wr_state *wr_mas) | |
2204 | { | |
2205 | struct ma_state *mas = wr_mas->mas; | |
97f7e094 | 2206 | unsigned char count, offset; |
54a611b6 LH |
2207 | |
2208 | if (unlikely(ma_is_dense(wr_mas->type))) { | |
2209 | wr_mas->r_max = wr_mas->r_min = mas->index; | |
2210 | mas->offset = mas->index = mas->min; | |
2211 | return; | |
2212 | } | |
2213 | ||
2214 | wr_mas->node = mas_mn(wr_mas->mas); | |
2215 | wr_mas->pivots = ma_pivots(wr_mas->node, wr_mas->type); | |
0de56e38 LH |
2216 | count = mas->end = ma_data_end(wr_mas->node, wr_mas->type, |
2217 | wr_mas->pivots, mas->max); | |
54a611b6 | 2218 | offset = mas->offset; |
54a611b6 | 2219 | |
97f7e094 PZ |
2220 | while (offset < count && mas->index > wr_mas->pivots[offset]) |
2221 | offset++; | |
54a611b6 | 2222 | |
97f7e094 PZ |
2223 | wr_mas->r_max = offset < count ? wr_mas->pivots[offset] : mas->max; |
2224 | wr_mas->r_min = mas_safe_min(mas, wr_mas->pivots, offset); | |
54a611b6 LH |
2225 | wr_mas->offset_end = mas->offset = offset; |
2226 | } | |
2227 | ||
54a611b6 LH |
2228 | /* |
2229 | * mast_rebalance_next() - Rebalance against the next node | |
2230 | * @mast: The maple subtree state | |
2231 | * @old_r: The encoded maple node to the right (next node). | |
2232 | */ | |
2233 | static inline void mast_rebalance_next(struct maple_subtree_state *mast) | |
2234 | { | |
2235 | unsigned char b_end = mast->bn->b_end; | |
2236 | ||
2237 | mas_mab_cp(mast->orig_r, 0, mt_slot_count(mast->orig_r->node), | |
2238 | mast->bn, b_end); | |
2239 | mast->orig_r->last = mast->orig_r->max; | |
2240 | } | |
2241 | ||
2242 | /* | |
2243 | * mast_rebalance_prev() - Rebalance against the previous node | |
2244 | * @mast: The maple subtree state | |
2245 | * @old_l: The encoded maple node to the left (previous node) | |
2246 | */ | |
2247 | static inline void mast_rebalance_prev(struct maple_subtree_state *mast) | |
2248 | { | |
2249 | unsigned char end = mas_data_end(mast->orig_l) + 1; | |
2250 | unsigned char b_end = mast->bn->b_end; | |
2251 | ||
2252 | mab_shift_right(mast->bn, end); | |
2253 | mas_mab_cp(mast->orig_l, 0, end - 1, mast->bn, 0); | |
2254 | mast->l->min = mast->orig_l->min; | |
2255 | mast->orig_l->index = mast->orig_l->min; | |
2256 | mast->bn->b_end = end + b_end; | |
2257 | mast->l->offset += end; | |
2258 | } | |
2259 | ||
2260 | /* | |
2261 | * mast_spanning_rebalance() - Rebalance nodes with nearest neighbour favouring | |
2262 | * the node to the right. Checking the nodes to the right then the left at each | |
530f745c | 2263 | * level upwards until root is reached. |
54a611b6 LH |
2264 | * Data is copied into the @mast->bn. |
2265 | * @mast: The maple_subtree_state. | |
2266 | */ | |
2267 | static inline | |
2268 | bool mast_spanning_rebalance(struct maple_subtree_state *mast) | |
2269 | { | |
2270 | struct ma_state r_tmp = *mast->orig_r; | |
2271 | struct ma_state l_tmp = *mast->orig_l; | |
54a611b6 LH |
2272 | unsigned char depth = 0; |
2273 | ||
54a611b6 LH |
2274 | do { |
2275 | mas_ascend(mast->orig_r); | |
2276 | mas_ascend(mast->orig_l); | |
2277 | depth++; | |
54a611b6 | 2278 | if (mast->orig_r->offset < mas_data_end(mast->orig_r)) { |
54a611b6 LH |
2279 | mast->orig_r->offset++; |
2280 | do { | |
2281 | mas_descend(mast->orig_r); | |
2282 | mast->orig_r->offset = 0; | |
530f745c | 2283 | } while (--depth); |
54a611b6 LH |
2284 | |
2285 | mast_rebalance_next(mast); | |
54a611b6 LH |
2286 | *mast->orig_l = l_tmp; |
2287 | return true; | |
54a611b6 | 2288 | } else if (mast->orig_l->offset != 0) { |
54a611b6 LH |
2289 | mast->orig_l->offset--; |
2290 | do { | |
2291 | mas_descend(mast->orig_l); | |
2292 | mast->orig_l->offset = | |
2293 | mas_data_end(mast->orig_l); | |
530f745c | 2294 | } while (--depth); |
54a611b6 LH |
2295 | |
2296 | mast_rebalance_prev(mast); | |
54a611b6 LH |
2297 | *mast->orig_r = r_tmp; |
2298 | return true; | |
2299 | } | |
2300 | } while (!mte_is_root(mast->orig_r->node)); | |
2301 | ||
2302 | *mast->orig_r = r_tmp; | |
2303 | *mast->orig_l = l_tmp; | |
2304 | return false; | |
2305 | } | |
2306 | ||
2307 | /* | |
530f745c | 2308 | * mast_ascend() - Ascend the original left and right maple states. |
54a611b6 LH |
2309 | * @mast: the maple subtree state. |
2310 | * | |
530f745c LH |
2311 | * Ascend the original left and right sides. Set the offsets to point to the |
2312 | * data already in the new tree (@mast->l and @mast->r). | |
54a611b6 | 2313 | */ |
530f745c | 2314 | static inline void mast_ascend(struct maple_subtree_state *mast) |
54a611b6 LH |
2315 | { |
2316 | MA_WR_STATE(wr_mas, mast->orig_r, NULL); | |
54a611b6 LH |
2317 | mas_ascend(mast->orig_l); |
2318 | mas_ascend(mast->orig_r); | |
54a611b6 LH |
2319 | |
2320 | mast->orig_r->offset = 0; | |
2321 | mast->orig_r->index = mast->r->max; | |
2322 | /* last should be larger than or equal to index */ | |
2323 | if (mast->orig_r->last < mast->orig_r->index) | |
2324 | mast->orig_r->last = mast->orig_r->index; | |
530f745c | 2325 | |
54a611b6 LH |
2326 | wr_mas.type = mte_node_type(mast->orig_r->node); |
2327 | mas_wr_node_walk(&wr_mas); | |
2328 | /* Set up the left side of things */ | |
2329 | mast->orig_l->offset = 0; | |
2330 | mast->orig_l->index = mast->l->min; | |
2331 | wr_mas.mas = mast->orig_l; | |
2332 | wr_mas.type = mte_node_type(mast->orig_l->node); | |
2333 | mas_wr_node_walk(&wr_mas); | |
2334 | ||
2335 | mast->bn->type = wr_mas.type; | |
2336 | } | |
2337 | ||
2338 | /* | |
2339 | * mas_new_ma_node() - Create and return a new maple node. Helper function. | |
2340 | * @mas: the maple state with the allocations. | |
2341 | * @b_node: the maple_big_node with the type encoding. | |
2342 | * | |
2343 | * Use the node type from the maple_big_node to allocate a new node from the | |
2344 | * ma_state. This function exists mainly for code readability. | |
2345 | * | |
2346 | * Return: A new maple encoded node | |
2347 | */ | |
2348 | static inline struct maple_enode | |
2349 | *mas_new_ma_node(struct ma_state *mas, struct maple_big_node *b_node) | |
2350 | { | |
2351 | return mt_mk_node(ma_mnode_ptr(mas_pop_node(mas)), b_node->type); | |
2352 | } | |
2353 | ||
2354 | /* | |
2355 | * mas_mab_to_node() - Set up right and middle nodes | |
2356 | * | |
2357 | * @mas: the maple state that contains the allocations. | |
2358 | * @b_node: the node which contains the data. | |
2359 | * @left: The pointer which will have the left node | |
2360 | * @right: The pointer which may have the right node | |
2361 | * @middle: the pointer which may have the middle node (rare) | |
2362 | * @mid_split: the split location for the middle node | |
2363 | * | |
2364 | * Return: the split of left. | |
2365 | */ | |
2366 | static inline unsigned char mas_mab_to_node(struct ma_state *mas, | |
2367 | struct maple_big_node *b_node, struct maple_enode **left, | |
2368 | struct maple_enode **right, struct maple_enode **middle, | |
2369 | unsigned char *mid_split, unsigned long min) | |
2370 | { | |
2371 | unsigned char split = 0; | |
2372 | unsigned char slot_count = mt_slots[b_node->type]; | |
2373 | ||
2374 | *left = mas_new_ma_node(mas, b_node); | |
2375 | *right = NULL; | |
2376 | *middle = NULL; | |
2377 | *mid_split = 0; | |
2378 | ||
2379 | if (b_node->b_end < slot_count) { | |
2380 | split = b_node->b_end; | |
2381 | } else { | |
2382 | split = mab_calc_split(mas, b_node, mid_split, min); | |
2383 | *right = mas_new_ma_node(mas, b_node); | |
2384 | } | |
2385 | ||
2386 | if (*mid_split) | |
2387 | *middle = mas_new_ma_node(mas, b_node); | |
2388 | ||
2389 | return split; | |
2390 | ||
2391 | } | |
2392 | ||
2393 | /* | |
2394 | * mab_set_b_end() - Add entry to b_node at b_node->b_end and increment the end | |
2395 | * pointer. | |
2396 | * @b_node - the big node to add the entry | |
2397 | * @mas - the maple state to get the pivot (mas->max) | |
2398 | * @entry - the entry to add, if NULL nothing happens. | |
2399 | */ | |
2400 | static inline void mab_set_b_end(struct maple_big_node *b_node, | |
2401 | struct ma_state *mas, | |
2402 | void *entry) | |
2403 | { | |
2404 | if (!entry) | |
2405 | return; | |
2406 | ||
2407 | b_node->slot[b_node->b_end] = entry; | |
2408 | if (mt_is_alloc(mas->tree)) | |
2409 | b_node->gap[b_node->b_end] = mas_max_gap(mas); | |
2410 | b_node->pivot[b_node->b_end++] = mas->max; | |
2411 | } | |
2412 | ||
2413 | /* | |
2414 | * mas_set_split_parent() - combine_then_separate helper function. Sets the parent | |
2415 | * of @mas->node to either @left or @right, depending on @slot and @split | |
2416 | * | |
2417 | * @mas - the maple state with the node that needs a parent | |
2418 | * @left - possible parent 1 | |
2419 | * @right - possible parent 2 | |
2420 | * @slot - the slot the mas->node was placed | |
2421 | * @split - the split location between @left and @right | |
2422 | */ | |
2423 | static inline void mas_set_split_parent(struct ma_state *mas, | |
2424 | struct maple_enode *left, | |
2425 | struct maple_enode *right, | |
2426 | unsigned char *slot, unsigned char split) | |
2427 | { | |
2428 | if (mas_is_none(mas)) | |
2429 | return; | |
2430 | ||
2431 | if ((*slot) <= split) | |
bf96715e | 2432 | mas_set_parent(mas, mas->node, left, *slot); |
54a611b6 | 2433 | else if (right) |
bf96715e | 2434 | mas_set_parent(mas, mas->node, right, (*slot) - split - 1); |
54a611b6 LH |
2435 | |
2436 | (*slot)++; | |
2437 | } | |
2438 | ||
2439 | /* | |
2440 | * mte_mid_split_check() - Check if the next node passes the mid-split | |
2441 | * @**l: Pointer to left encoded maple node. | |
2442 | * @**m: Pointer to middle encoded maple node. | |
2443 | * @**r: Pointer to right encoded maple node. | |
2444 | * @slot: The offset | |
2445 | * @*split: The split location. | |
2446 | * @mid_split: The middle split. | |
2447 | */ | |
2448 | static inline void mte_mid_split_check(struct maple_enode **l, | |
2449 | struct maple_enode **r, | |
2450 | struct maple_enode *right, | |
2451 | unsigned char slot, | |
2452 | unsigned char *split, | |
2453 | unsigned char mid_split) | |
2454 | { | |
2455 | if (*r == right) | |
2456 | return; | |
2457 | ||
2458 | if (slot < mid_split) | |
2459 | return; | |
2460 | ||
2461 | *l = *r; | |
2462 | *r = right; | |
2463 | *split = mid_split; | |
2464 | } | |
2465 | ||
2466 | /* | |
2467 | * mast_set_split_parents() - Helper function to set three nodes parents. Slot | |
2468 | * is taken from @mast->l. | |
2469 | * @mast - the maple subtree state | |
2470 | * @left - the left node | |
2471 | * @right - the right node | |
2472 | * @split - the split location. | |
2473 | */ | |
2474 | static inline void mast_set_split_parents(struct maple_subtree_state *mast, | |
2475 | struct maple_enode *left, | |
2476 | struct maple_enode *middle, | |
2477 | struct maple_enode *right, | |
2478 | unsigned char split, | |
2479 | unsigned char mid_split) | |
2480 | { | |
2481 | unsigned char slot; | |
2482 | struct maple_enode *l = left; | |
2483 | struct maple_enode *r = right; | |
2484 | ||
2485 | if (mas_is_none(mast->l)) | |
2486 | return; | |
2487 | ||
2488 | if (middle) | |
2489 | r = middle; | |
2490 | ||
2491 | slot = mast->l->offset; | |
2492 | ||
2493 | mte_mid_split_check(&l, &r, right, slot, &split, mid_split); | |
2494 | mas_set_split_parent(mast->l, l, r, &slot, split); | |
2495 | ||
2496 | mte_mid_split_check(&l, &r, right, slot, &split, mid_split); | |
2497 | mas_set_split_parent(mast->m, l, r, &slot, split); | |
2498 | ||
2499 | mte_mid_split_check(&l, &r, right, slot, &split, mid_split); | |
2500 | mas_set_split_parent(mast->r, l, r, &slot, split); | |
2501 | } | |
2502 | ||
2503 | /* | |
d5f6057c | 2504 | * mas_topiary_node() - Dispose of a single node |
530f745c LH |
2505 | * @mas: The maple state for pushing nodes |
2506 | * @enode: The encoded maple node | |
2507 | * @in_rcu: If the tree is in rcu mode | |
54a611b6 | 2508 | * |
530f745c | 2509 | * The node will either be RCU freed or pushed back on the maple state. |
54a611b6 | 2510 | */ |
530f745c | 2511 | static inline void mas_topiary_node(struct ma_state *mas, |
067311d3 | 2512 | struct ma_state *tmp_mas, bool in_rcu) |
54a611b6 | 2513 | { |
530f745c | 2514 | struct maple_node *tmp; |
067311d3 | 2515 | struct maple_enode *enode; |
1238f6a2 | 2516 | |
067311d3 | 2517 | if (mas_is_none(tmp_mas)) |
530f745c | 2518 | return; |
1238f6a2 | 2519 | |
067311d3 | 2520 | enode = tmp_mas->node; |
530f745c LH |
2521 | tmp = mte_to_node(enode); |
2522 | mte_set_node_dead(enode); | |
2523 | if (in_rcu) | |
2524 | ma_free_rcu(tmp); | |
2525 | else | |
2526 | mas_push_node(mas, tmp); | |
2527 | } | |
54a611b6 | 2528 | |
530f745c LH |
2529 | /* |
2530 | * mas_topiary_replace() - Replace the data with new data, then repair the | |
2531 | * parent links within the new tree. Iterate over the dead sub-tree and collect | |
2532 | * the dead subtrees and topiary the nodes that are no longer of use. | |
2533 | * | |
2534 | * The new tree will have up to three children with the correct parent. Keep | |
2535 | * track of the new entries as they need to be followed to find the next level | |
2536 | * of new entries. | |
2537 | * | |
2538 | * The old tree will have up to three children with the old parent. Keep track | |
2539 | * of the old entries as they may have more nodes below replaced. Nodes within | |
2540 | * [index, last] are dead subtrees, others need to be freed and followed. | |
2541 | * | |
2542 | * @mas: The maple state pointing at the new data | |
2543 | * @old_enode: The maple encoded node being replaced | |
2544 | * | |
2545 | */ | |
2546 | static inline void mas_topiary_replace(struct ma_state *mas, | |
2547 | struct maple_enode *old_enode) | |
2548 | { | |
2549 | struct ma_state tmp[3], tmp_next[3]; | |
2550 | MA_TOPIARY(subtrees, mas->tree); | |
2551 | bool in_rcu; | |
2552 | int i, n; | |
2553 | ||
2554 | /* Place data in tree & then mark node as old */ | |
1238f6a2 | 2555 | mas_put_in_tree(mas, old_enode); |
54a611b6 | 2556 | |
530f745c LH |
2557 | /* Update the parent pointers in the tree */ |
2558 | tmp[0] = *mas; | |
2559 | tmp[0].offset = 0; | |
067311d3 LH |
2560 | tmp[1].status = ma_none; |
2561 | tmp[2].status = ma_none; | |
530f745c LH |
2562 | while (!mte_is_leaf(tmp[0].node)) { |
2563 | n = 0; | |
2564 | for (i = 0; i < 3; i++) { | |
2565 | if (mas_is_none(&tmp[i])) | |
2566 | continue; | |
54a611b6 | 2567 | |
530f745c LH |
2568 | while (n < 3) { |
2569 | if (!mas_find_child(&tmp[i], &tmp_next[n])) | |
2570 | break; | |
2571 | n++; | |
2572 | } | |
54a611b6 | 2573 | |
530f745c LH |
2574 | mas_adopt_children(&tmp[i], tmp[i].node); |
2575 | } | |
54a611b6 | 2576 | |
530f745c LH |
2577 | if (MAS_WARN_ON(mas, n == 0)) |
2578 | break; | |
54a611b6 | 2579 | |
530f745c | 2580 | while (n < 3) |
067311d3 | 2581 | tmp_next[n++].status = ma_none; |
530f745c LH |
2582 | |
2583 | for (i = 0; i < 3; i++) | |
2584 | tmp[i] = tmp_next[i]; | |
2585 | } | |
2586 | ||
2587 | /* Collect the old nodes that need to be discarded */ | |
2588 | if (mte_is_leaf(old_enode)) | |
2589 | return mas_free(mas, old_enode); | |
2590 | ||
2591 | tmp[0] = *mas; | |
2592 | tmp[0].offset = 0; | |
2593 | tmp[0].node = old_enode; | |
067311d3 LH |
2594 | tmp[1].status = ma_none; |
2595 | tmp[2].status = ma_none; | |
530f745c LH |
2596 | in_rcu = mt_in_rcu(mas->tree); |
2597 | do { | |
2598 | n = 0; | |
2599 | for (i = 0; i < 3; i++) { | |
2600 | if (mas_is_none(&tmp[i])) | |
2601 | continue; | |
2602 | ||
2603 | while (n < 3) { | |
2604 | if (!mas_find_child(&tmp[i], &tmp_next[n])) | |
2605 | break; | |
2606 | ||
2607 | if ((tmp_next[n].min >= tmp_next->index) && | |
2608 | (tmp_next[n].max <= tmp_next->last)) { | |
2609 | mat_add(&subtrees, tmp_next[n].node); | |
067311d3 | 2610 | tmp_next[n].status = ma_none; |
530f745c LH |
2611 | } else { |
2612 | n++; | |
2613 | } | |
2614 | } | |
2615 | } | |
2616 | ||
2617 | if (MAS_WARN_ON(mas, n == 0)) | |
2618 | break; | |
2619 | ||
2620 | while (n < 3) | |
067311d3 | 2621 | tmp_next[n++].status = ma_none; |
530f745c LH |
2622 | |
2623 | for (i = 0; i < 3; i++) { | |
067311d3 | 2624 | mas_topiary_node(mas, &tmp[i], in_rcu); |
530f745c LH |
2625 | tmp[i] = tmp_next[i]; |
2626 | } | |
2627 | } while (!mte_is_leaf(tmp[0].node)); | |
2628 | ||
2629 | for (i = 0; i < 3; i++) | |
067311d3 | 2630 | mas_topiary_node(mas, &tmp[i], in_rcu); |
530f745c LH |
2631 | |
2632 | mas_mat_destroy(mas, &subtrees); | |
54a611b6 LH |
2633 | } |
2634 | ||
2635 | /* | |
530f745c | 2636 | * mas_wmb_replace() - Write memory barrier and replace |
54a611b6 | 2637 | * @mas: The maple state |
530f745c LH |
2638 | * @old: The old maple encoded node that is being replaced. |
2639 | * | |
2640 | * Updates gap as necessary. | |
54a611b6 | 2641 | */ |
530f745c LH |
2642 | static inline void mas_wmb_replace(struct ma_state *mas, |
2643 | struct maple_enode *old_enode) | |
54a611b6 | 2644 | { |
530f745c LH |
2645 | /* Insert the new data in the tree */ |
2646 | mas_topiary_replace(mas, old_enode); | |
2647 | ||
2648 | if (mte_is_leaf(mas->node)) | |
2649 | return; | |
2650 | ||
2651 | mas_update_gap(mas); | |
54a611b6 LH |
2652 | } |
2653 | ||
2654 | /* | |
2655 | * mast_cp_to_nodes() - Copy data out to nodes. | |
2656 | * @mast: The maple subtree state | |
2657 | * @left: The left encoded maple node | |
2658 | * @middle: The middle encoded maple node | |
2659 | * @right: The right encoded maple node | |
2660 | * @split: The location to split between left and (middle ? middle : right) | |
2661 | * @mid_split: The location to split between middle and right. | |
2662 | */ | |
2663 | static inline void mast_cp_to_nodes(struct maple_subtree_state *mast, | |
2664 | struct maple_enode *left, struct maple_enode *middle, | |
2665 | struct maple_enode *right, unsigned char split, unsigned char mid_split) | |
2666 | { | |
2667 | bool new_lmax = true; | |
2668 | ||
067311d3 LH |
2669 | mas_node_or_none(mast->l, left); |
2670 | mas_node_or_none(mast->m, middle); | |
2671 | mas_node_or_none(mast->r, right); | |
54a611b6 LH |
2672 | |
2673 | mast->l->min = mast->orig_l->min; | |
2674 | if (split == mast->bn->b_end) { | |
2675 | mast->l->max = mast->orig_r->max; | |
2676 | new_lmax = false; | |
2677 | } | |
2678 | ||
2679 | mab_mas_cp(mast->bn, 0, split, mast->l, new_lmax); | |
2680 | ||
2681 | if (middle) { | |
2682 | mab_mas_cp(mast->bn, 1 + split, mid_split, mast->m, true); | |
2683 | mast->m->min = mast->bn->pivot[split] + 1; | |
2684 | split = mid_split; | |
2685 | } | |
2686 | ||
2687 | mast->r->max = mast->orig_r->max; | |
2688 | if (right) { | |
2689 | mab_mas_cp(mast->bn, 1 + split, mast->bn->b_end, mast->r, false); | |
2690 | mast->r->min = mast->bn->pivot[split] + 1; | |
2691 | } | |
2692 | } | |
2693 | ||
2694 | /* | |
2695 | * mast_combine_cp_left - Copy in the original left side of the tree into the | |
2696 | * combined data set in the maple subtree state big node. | |
2697 | * @mast: The maple subtree state | |
2698 | */ | |
2699 | static inline void mast_combine_cp_left(struct maple_subtree_state *mast) | |
2700 | { | |
2701 | unsigned char l_slot = mast->orig_l->offset; | |
2702 | ||
2703 | if (!l_slot) | |
2704 | return; | |
2705 | ||
2706 | mas_mab_cp(mast->orig_l, 0, l_slot - 1, mast->bn, 0); | |
2707 | } | |
2708 | ||
2709 | /* | |
2710 | * mast_combine_cp_right: Copy in the original right side of the tree into the | |
2711 | * combined data set in the maple subtree state big node. | |
2712 | * @mast: The maple subtree state | |
2713 | */ | |
2714 | static inline void mast_combine_cp_right(struct maple_subtree_state *mast) | |
2715 | { | |
2716 | if (mast->bn->pivot[mast->bn->b_end - 1] >= mast->orig_r->max) | |
2717 | return; | |
2718 | ||
2719 | mas_mab_cp(mast->orig_r, mast->orig_r->offset + 1, | |
2720 | mt_slot_count(mast->orig_r->node), mast->bn, | |
2721 | mast->bn->b_end); | |
2722 | mast->orig_r->last = mast->orig_r->max; | |
2723 | } | |
2724 | ||
2725 | /* | |
2726 | * mast_sufficient: Check if the maple subtree state has enough data in the big | |
2727 | * node to create at least one sufficient node | |
2728 | * @mast: the maple subtree state | |
2729 | */ | |
2730 | static inline bool mast_sufficient(struct maple_subtree_state *mast) | |
2731 | { | |
2732 | if (mast->bn->b_end > mt_min_slot_count(mast->orig_l->node)) | |
2733 | return true; | |
2734 | ||
2735 | return false; | |
2736 | } | |
2737 | ||
2738 | /* | |
2739 | * mast_overflow: Check if there is too much data in the subtree state for a | |
2740 | * single node. | |
2741 | * @mast: The maple subtree state | |
2742 | */ | |
2743 | static inline bool mast_overflow(struct maple_subtree_state *mast) | |
2744 | { | |
2745 | if (mast->bn->b_end >= mt_slot_count(mast->orig_l->node)) | |
2746 | return true; | |
2747 | ||
2748 | return false; | |
2749 | } | |
2750 | ||
2751 | static inline void *mtree_range_walk(struct ma_state *mas) | |
2752 | { | |
2753 | unsigned long *pivots; | |
2754 | unsigned char offset; | |
2755 | struct maple_node *node; | |
2756 | struct maple_enode *next, *last; | |
2757 | enum maple_type type; | |
2758 | void __rcu **slots; | |
2759 | unsigned char end; | |
2760 | unsigned long max, min; | |
2761 | unsigned long prev_max, prev_min; | |
2762 | ||
1b9c9183 LB |
2763 | next = mas->node; |
2764 | min = mas->min; | |
54a611b6 LH |
2765 | max = mas->max; |
2766 | do { | |
54a611b6 LH |
2767 | last = next; |
2768 | node = mte_to_node(next); | |
2769 | type = mte_node_type(next); | |
2770 | pivots = ma_pivots(node, type); | |
2771 | end = ma_data_end(node, type, pivots, max); | |
a3c63c8c LH |
2772 | prev_min = min; |
2773 | prev_max = max; | |
2774 | if (pivots[0] >= mas->index) { | |
2775 | offset = 0; | |
2776 | max = pivots[0]; | |
54a611b6 LH |
2777 | goto next; |
2778 | } | |
2779 | ||
a3c63c8c LH |
2780 | offset = 1; |
2781 | while (offset < end) { | |
2782 | if (pivots[offset] >= mas->index) { | |
2783 | max = pivots[offset]; | |
2784 | break; | |
2785 | } | |
54a611b6 | 2786 | offset++; |
a3c63c8c | 2787 | } |
54a611b6 | 2788 | |
54a611b6 | 2789 | min = pivots[offset - 1] + 1; |
54a611b6 LH |
2790 | next: |
2791 | slots = ma_slots(node, type); | |
2792 | next = mt_slot(mas->tree, slots, offset); | |
2793 | if (unlikely(ma_dead_node(node))) | |
2794 | goto dead_node; | |
2795 | } while (!ma_is_leaf(type)); | |
2796 | ||
31c532a8 | 2797 | mas->end = end; |
54a611b6 LH |
2798 | mas->offset = offset; |
2799 | mas->index = min; | |
2800 | mas->last = max; | |
2801 | mas->min = prev_min; | |
2802 | mas->max = prev_max; | |
2803 | mas->node = last; | |
831978e3 | 2804 | return (void *)next; |
54a611b6 LH |
2805 | |
2806 | dead_node: | |
2807 | mas_reset(mas); | |
2808 | return NULL; | |
2809 | } | |
2810 | ||
2811 | /* | |
2812 | * mas_spanning_rebalance() - Rebalance across two nodes which may not be peers. | |
2813 | * @mas: The starting maple state | |
2814 | * @mast: The maple_subtree_state, keeps track of 4 maple states. | |
2815 | * @count: The estimated count of iterations needed. | |
2816 | * | |
2817 | * Follow the tree upwards from @l_mas and @r_mas for @count, or until the root | |
2818 | * is hit. First @b_node is split into two entries which are inserted into the | |
2819 | * next iteration of the loop. @b_node is returned populated with the final | |
2820 | * iteration. @mas is used to obtain allocations. orig_l_mas keeps track of the | |
2821 | * nodes that will remain active by using orig_l_mas->index and orig_l_mas->last | |
2822 | * to account of what has been copied into the new sub-tree. The update of | |
2823 | * orig_l_mas->last is used in mas_consume to find the slots that will need to | |
2824 | * be either freed or destroyed. orig_l_mas->depth keeps track of the height of | |
2825 | * the new sub-tree in case the sub-tree becomes the full tree. | |
2826 | * | |
2827 | * Return: the number of elements in b_node during the last loop. | |
2828 | */ | |
2829 | static int mas_spanning_rebalance(struct ma_state *mas, | |
2830 | struct maple_subtree_state *mast, unsigned char count) | |
2831 | { | |
2832 | unsigned char split, mid_split; | |
2833 | unsigned char slot = 0; | |
2834 | struct maple_enode *left = NULL, *middle = NULL, *right = NULL; | |
530f745c | 2835 | struct maple_enode *old_enode; |
54a611b6 LH |
2836 | |
2837 | MA_STATE(l_mas, mas->tree, mas->index, mas->index); | |
2838 | MA_STATE(r_mas, mas->tree, mas->index, mas->last); | |
2839 | MA_STATE(m_mas, mas->tree, mas->index, mas->index); | |
54a611b6 LH |
2840 | |
2841 | /* | |
2842 | * The tree needs to be rebalanced and leaves need to be kept at the same level. | |
2843 | * Rebalancing is done by use of the ``struct maple_topiary``. | |
2844 | */ | |
2845 | mast->l = &l_mas; | |
2846 | mast->m = &m_mas; | |
2847 | mast->r = &r_mas; | |
067311d3 | 2848 | l_mas.status = r_mas.status = m_mas.status = ma_none; |
0abb964a LH |
2849 | |
2850 | /* Check if this is not root and has sufficient data. */ | |
2851 | if (((mast->orig_l->min != 0) || (mast->orig_r->max != ULONG_MAX)) && | |
54a611b6 LH |
2852 | unlikely(mast->bn->b_end <= mt_min_slots[mast->bn->type])) |
2853 | mast_spanning_rebalance(mast); | |
2854 | ||
530f745c | 2855 | l_mas.depth = 0; |
54a611b6 LH |
2856 | |
2857 | /* | |
2858 | * Each level of the tree is examined and balanced, pushing data to the left or | |
2859 | * right, or rebalancing against left or right nodes is employed to avoid | |
2860 | * rippling up the tree to limit the amount of churn. Once a new sub-section of | |
2861 | * the tree is created, there may be a mix of new and old nodes. The old nodes | |
2862 | * will have the incorrect parent pointers and currently be in two trees: the | |
2863 | * original tree and the partially new tree. To remedy the parent pointers in | |
2864 | * the old tree, the new data is swapped into the active tree and a walk down | |
2865 | * the tree is performed and the parent pointers are updated. | |
530f745c | 2866 | * See mas_topiary_replace() for more information. |
54a611b6 LH |
2867 | */ |
2868 | while (count--) { | |
2869 | mast->bn->b_end--; | |
2870 | mast->bn->type = mte_node_type(mast->orig_l->node); | |
2871 | split = mas_mab_to_node(mas, mast->bn, &left, &right, &middle, | |
2872 | &mid_split, mast->orig_l->min); | |
2873 | mast_set_split_parents(mast, left, middle, right, split, | |
2874 | mid_split); | |
2875 | mast_cp_to_nodes(mast, left, middle, right, split, mid_split); | |
2876 | ||
2877 | /* | |
2878 | * Copy data from next level in the tree to mast->bn from next | |
2879 | * iteration | |
2880 | */ | |
2881 | memset(mast->bn, 0, sizeof(struct maple_big_node)); | |
2882 | mast->bn->type = mte_node_type(left); | |
530f745c | 2883 | l_mas.depth++; |
54a611b6 LH |
2884 | |
2885 | /* Root already stored in l->node. */ | |
2886 | if (mas_is_root_limits(mast->l)) | |
2887 | goto new_root; | |
2888 | ||
530f745c | 2889 | mast_ascend(mast); |
54a611b6 LH |
2890 | mast_combine_cp_left(mast); |
2891 | l_mas.offset = mast->bn->b_end; | |
2892 | mab_set_b_end(mast->bn, &l_mas, left); | |
2893 | mab_set_b_end(mast->bn, &m_mas, middle); | |
2894 | mab_set_b_end(mast->bn, &r_mas, right); | |
2895 | ||
2896 | /* Copy anything necessary out of the right node. */ | |
2897 | mast_combine_cp_right(mast); | |
54a611b6 LH |
2898 | mast->orig_l->last = mast->orig_l->max; |
2899 | ||
2900 | if (mast_sufficient(mast)) | |
2901 | continue; | |
2902 | ||
2903 | if (mast_overflow(mast)) | |
2904 | continue; | |
2905 | ||
2906 | /* May be a new root stored in mast->bn */ | |
2907 | if (mas_is_root_limits(mast->orig_l)) | |
2908 | break; | |
2909 | ||
2910 | mast_spanning_rebalance(mast); | |
2911 | ||
2912 | /* rebalancing from other nodes may require another loop. */ | |
2913 | if (!count) | |
2914 | count++; | |
2915 | } | |
2916 | ||
2917 | l_mas.node = mt_mk_node(ma_mnode_ptr(mas_pop_node(mas)), | |
2918 | mte_node_type(mast->orig_l->node)); | |
530f745c | 2919 | l_mas.depth++; |
54a611b6 | 2920 | mab_mas_cp(mast->bn, 0, mt_slots[mast->bn->type] - 1, &l_mas, true); |
bf96715e | 2921 | mas_set_parent(mas, left, l_mas.node, slot); |
54a611b6 | 2922 | if (middle) |
bf96715e | 2923 | mas_set_parent(mas, middle, l_mas.node, ++slot); |
54a611b6 LH |
2924 | |
2925 | if (right) | |
bf96715e | 2926 | mas_set_parent(mas, right, l_mas.node, ++slot); |
54a611b6 LH |
2927 | |
2928 | if (mas_is_root_limits(mast->l)) { | |
2929 | new_root: | |
530f745c LH |
2930 | mas_mn(mast->l)->parent = ma_parent_ptr(mas_tree_parent(mas)); |
2931 | while (!mte_is_root(mast->orig_l->node)) | |
2932 | mast_ascend(mast); | |
54a611b6 LH |
2933 | } else { |
2934 | mas_mn(&l_mas)->parent = mas_mn(mast->orig_l)->parent; | |
2935 | } | |
2936 | ||
530f745c LH |
2937 | old_enode = mast->orig_l->node; |
2938 | mas->depth = l_mas.depth; | |
2939 | mas->node = l_mas.node; | |
2940 | mas->min = l_mas.min; | |
2941 | mas->max = l_mas.max; | |
2942 | mas->offset = l_mas.offset; | |
2943 | mas_wmb_replace(mas, old_enode); | |
54a611b6 LH |
2944 | mtree_range_walk(mas); |
2945 | return mast->bn->b_end; | |
2946 | } | |
2947 | ||
2948 | /* | |
2949 | * mas_rebalance() - Rebalance a given node. | |
2950 | * @mas: The maple state | |
2951 | * @b_node: The big maple node. | |
2952 | * | |
2953 | * Rebalance two nodes into a single node or two new nodes that are sufficient. | |
2954 | * Continue upwards until tree is sufficient. | |
2955 | * | |
2956 | * Return: the number of elements in b_node during the last loop. | |
2957 | */ | |
2958 | static inline int mas_rebalance(struct ma_state *mas, | |
2959 | struct maple_big_node *b_node) | |
2960 | { | |
2961 | char empty_count = mas_mt_height(mas); | |
2962 | struct maple_subtree_state mast; | |
2963 | unsigned char shift, b_end = ++b_node->b_end; | |
2964 | ||
2965 | MA_STATE(l_mas, mas->tree, mas->index, mas->last); | |
2966 | MA_STATE(r_mas, mas->tree, mas->index, mas->last); | |
2967 | ||
2968 | trace_ma_op(__func__, mas); | |
2969 | ||
2970 | /* | |
2971 | * Rebalancing occurs if a node is insufficient. Data is rebalanced | |
2972 | * against the node to the right if it exists, otherwise the node to the | |
2973 | * left of this node is rebalanced against this node. If rebalancing | |
2974 | * causes just one node to be produced instead of two, then the parent | |
2975 | * is also examined and rebalanced if it is insufficient. Every level | |
2976 | * tries to combine the data in the same way. If one node contains the | |
2977 | * entire range of the tree, then that node is used as a new root node. | |
2978 | */ | |
c108df76 | 2979 | mas_node_count(mas, empty_count * 2 - 1); |
54a611b6 LH |
2980 | if (mas_is_err(mas)) |
2981 | return 0; | |
2982 | ||
2983 | mast.orig_l = &l_mas; | |
2984 | mast.orig_r = &r_mas; | |
2985 | mast.bn = b_node; | |
2986 | mast.bn->type = mte_node_type(mas->node); | |
2987 | ||
2988 | l_mas = r_mas = *mas; | |
2989 | ||
2990 | if (mas_next_sibling(&r_mas)) { | |
2991 | mas_mab_cp(&r_mas, 0, mt_slot_count(r_mas.node), b_node, b_end); | |
2992 | r_mas.last = r_mas.index = r_mas.max; | |
2993 | } else { | |
2994 | mas_prev_sibling(&l_mas); | |
2995 | shift = mas_data_end(&l_mas) + 1; | |
2996 | mab_shift_right(b_node, shift); | |
2997 | mas->offset += shift; | |
2998 | mas_mab_cp(&l_mas, 0, shift - 1, b_node, 0); | |
2999 | b_node->b_end = shift + b_end; | |
3000 | l_mas.index = l_mas.last = l_mas.min; | |
3001 | } | |
3002 | ||
3003 | return mas_spanning_rebalance(mas, &mast, empty_count); | |
3004 | } | |
3005 | ||
3006 | /* | |
3007 | * mas_destroy_rebalance() - Rebalance left-most node while destroying the maple | |
3008 | * state. | |
3009 | * @mas: The maple state | |
3010 | * @end: The end of the left-most node. | |
3011 | * | |
3012 | * During a mass-insert event (such as forking), it may be necessary to | |
3013 | * rebalance the left-most node when it is not sufficient. | |
3014 | */ | |
3015 | static inline void mas_destroy_rebalance(struct ma_state *mas, unsigned char end) | |
3016 | { | |
3017 | enum maple_type mt = mte_node_type(mas->node); | |
3018 | struct maple_node reuse, *newnode, *parent, *new_left, *left, *node; | |
72bcf4aa | 3019 | struct maple_enode *eparent, *old_eparent; |
54a611b6 LH |
3020 | unsigned char offset, tmp, split = mt_slots[mt] / 2; |
3021 | void __rcu **l_slots, **slots; | |
3022 | unsigned long *l_pivs, *pivs, gap; | |
3023 | bool in_rcu = mt_in_rcu(mas->tree); | |
3024 | ||
3025 | MA_STATE(l_mas, mas->tree, mas->index, mas->last); | |
3026 | ||
3027 | l_mas = *mas; | |
3028 | mas_prev_sibling(&l_mas); | |
3029 | ||
3030 | /* set up node. */ | |
3031 | if (in_rcu) { | |
3032 | /* Allocate for both left and right as well as parent. */ | |
3033 | mas_node_count(mas, 3); | |
3034 | if (mas_is_err(mas)) | |
3035 | return; | |
3036 | ||
3037 | newnode = mas_pop_node(mas); | |
3038 | } else { | |
3039 | newnode = &reuse; | |
3040 | } | |
3041 | ||
3042 | node = mas_mn(mas); | |
3043 | newnode->parent = node->parent; | |
3044 | slots = ma_slots(newnode, mt); | |
3045 | pivs = ma_pivots(newnode, mt); | |
3046 | left = mas_mn(&l_mas); | |
3047 | l_slots = ma_slots(left, mt); | |
3048 | l_pivs = ma_pivots(left, mt); | |
3049 | if (!l_slots[split]) | |
3050 | split++; | |
3051 | tmp = mas_data_end(&l_mas) - split; | |
3052 | ||
3053 | memcpy(slots, l_slots + split + 1, sizeof(void *) * tmp); | |
3054 | memcpy(pivs, l_pivs + split + 1, sizeof(unsigned long) * tmp); | |
3055 | pivs[tmp] = l_mas.max; | |
3056 | memcpy(slots + tmp, ma_slots(node, mt), sizeof(void *) * end); | |
3057 | memcpy(pivs + tmp, ma_pivots(node, mt), sizeof(unsigned long) * end); | |
3058 | ||
3059 | l_mas.max = l_pivs[split]; | |
3060 | mas->min = l_mas.max + 1; | |
72bcf4aa | 3061 | old_eparent = mt_mk_node(mte_parent(l_mas.node), |
afc754c6 | 3062 | mas_parent_type(&l_mas, l_mas.node)); |
54a611b6 LH |
3063 | tmp += end; |
3064 | if (!in_rcu) { | |
3065 | unsigned char max_p = mt_pivots[mt]; | |
3066 | unsigned char max_s = mt_slots[mt]; | |
3067 | ||
3068 | if (tmp < max_p) | |
3069 | memset(pivs + tmp, 0, | |
fb20e99a | 3070 | sizeof(unsigned long) * (max_p - tmp)); |
54a611b6 LH |
3071 | |
3072 | if (tmp < mt_slots[mt]) | |
3073 | memset(slots + tmp, 0, sizeof(void *) * (max_s - tmp)); | |
3074 | ||
3075 | memcpy(node, newnode, sizeof(struct maple_node)); | |
3076 | ma_set_meta(node, mt, 0, tmp - 1); | |
72bcf4aa | 3077 | mte_set_pivot(old_eparent, mte_parent_slot(l_mas.node), |
54a611b6 LH |
3078 | l_pivs[split]); |
3079 | ||
3080 | /* Remove data from l_pivs. */ | |
3081 | tmp = split + 1; | |
3082 | memset(l_pivs + tmp, 0, sizeof(unsigned long) * (max_p - tmp)); | |
3083 | memset(l_slots + tmp, 0, sizeof(void *) * (max_s - tmp)); | |
3084 | ma_set_meta(left, mt, 0, split); | |
72bcf4aa | 3085 | eparent = old_eparent; |
54a611b6 LH |
3086 | |
3087 | goto done; | |
3088 | } | |
3089 | ||
3090 | /* RCU requires replacing both l_mas, mas, and parent. */ | |
3091 | mas->node = mt_mk_node(newnode, mt); | |
3092 | ma_set_meta(newnode, mt, 0, tmp); | |
3093 | ||
3094 | new_left = mas_pop_node(mas); | |
3095 | new_left->parent = left->parent; | |
3096 | mt = mte_node_type(l_mas.node); | |
3097 | slots = ma_slots(new_left, mt); | |
3098 | pivs = ma_pivots(new_left, mt); | |
3099 | memcpy(slots, l_slots, sizeof(void *) * split); | |
3100 | memcpy(pivs, l_pivs, sizeof(unsigned long) * split); | |
3101 | ma_set_meta(new_left, mt, 0, split); | |
3102 | l_mas.node = mt_mk_node(new_left, mt); | |
3103 | ||
3104 | /* replace parent. */ | |
3105 | offset = mte_parent_slot(mas->node); | |
afc754c6 | 3106 | mt = mas_parent_type(&l_mas, l_mas.node); |
54a611b6 LH |
3107 | parent = mas_pop_node(mas); |
3108 | slots = ma_slots(parent, mt); | |
3109 | pivs = ma_pivots(parent, mt); | |
72bcf4aa | 3110 | memcpy(parent, mte_to_node(old_eparent), sizeof(struct maple_node)); |
54a611b6 LH |
3111 | rcu_assign_pointer(slots[offset], mas->node); |
3112 | rcu_assign_pointer(slots[offset - 1], l_mas.node); | |
3113 | pivs[offset - 1] = l_mas.max; | |
3114 | eparent = mt_mk_node(parent, mt); | |
3115 | done: | |
3116 | gap = mas_leaf_max_gap(mas); | |
3117 | mte_set_gap(eparent, mte_parent_slot(mas->node), gap); | |
3118 | gap = mas_leaf_max_gap(&l_mas); | |
3119 | mte_set_gap(eparent, mte_parent_slot(l_mas.node), gap); | |
3120 | mas_ascend(mas); | |
3121 | ||
72bcf4aa LH |
3122 | if (in_rcu) { |
3123 | mas_replace_node(mas, old_eparent); | |
3124 | mas_adopt_children(mas, mas->node); | |
3125 | } | |
54a611b6 LH |
3126 | |
3127 | mas_update_gap(mas); | |
3128 | } | |
3129 | ||
3130 | /* | |
3131 | * mas_split_final_node() - Split the final node in a subtree operation. | |
3132 | * @mast: the maple subtree state | |
3133 | * @mas: The maple state | |
3134 | * @height: The height of the tree in case it's a new root. | |
3135 | */ | |
d9d9bd97 | 3136 | static inline void mas_split_final_node(struct maple_subtree_state *mast, |
54a611b6 LH |
3137 | struct ma_state *mas, int height) |
3138 | { | |
3139 | struct maple_enode *ancestor; | |
3140 | ||
3141 | if (mte_is_root(mas->node)) { | |
3142 | if (mt_is_alloc(mas->tree)) | |
3143 | mast->bn->type = maple_arange_64; | |
3144 | else | |
3145 | mast->bn->type = maple_range_64; | |
3146 | mas->depth = height; | |
3147 | } | |
3148 | /* | |
3149 | * Only a single node is used here, could be root. | |
3150 | * The Big_node data should just fit in a single node. | |
3151 | */ | |
3152 | ancestor = mas_new_ma_node(mas, mast->bn); | |
bf96715e LH |
3153 | mas_set_parent(mas, mast->l->node, ancestor, mast->l->offset); |
3154 | mas_set_parent(mas, mast->r->node, ancestor, mast->r->offset); | |
54a611b6 LH |
3155 | mte_to_node(ancestor)->parent = mas_mn(mas)->parent; |
3156 | ||
3157 | mast->l->node = ancestor; | |
3158 | mab_mas_cp(mast->bn, 0, mt_slots[mast->bn->type] - 1, mast->l, true); | |
3159 | mas->offset = mast->bn->b_end - 1; | |
54a611b6 LH |
3160 | } |
3161 | ||
3162 | /* | |
3163 | * mast_fill_bnode() - Copy data into the big node in the subtree state | |
3164 | * @mast: The maple subtree state | |
3165 | * @mas: the maple state | |
3166 | * @skip: The number of entries to skip for new nodes insertion. | |
3167 | */ | |
3168 | static inline void mast_fill_bnode(struct maple_subtree_state *mast, | |
3169 | struct ma_state *mas, | |
3170 | unsigned char skip) | |
3171 | { | |
3172 | bool cp = true; | |
54a611b6 LH |
3173 | unsigned char split; |
3174 | ||
3175 | memset(mast->bn->gap, 0, sizeof(unsigned long) * ARRAY_SIZE(mast->bn->gap)); | |
3176 | memset(mast->bn->slot, 0, sizeof(unsigned long) * ARRAY_SIZE(mast->bn->slot)); | |
3177 | memset(mast->bn->pivot, 0, sizeof(unsigned long) * ARRAY_SIZE(mast->bn->pivot)); | |
3178 | mast->bn->b_end = 0; | |
3179 | ||
3180 | if (mte_is_root(mas->node)) { | |
3181 | cp = false; | |
3182 | } else { | |
3183 | mas_ascend(mas); | |
54a611b6 LH |
3184 | mas->offset = mte_parent_slot(mas->node); |
3185 | } | |
3186 | ||
3187 | if (cp && mast->l->offset) | |
3188 | mas_mab_cp(mas, 0, mast->l->offset - 1, mast->bn, 0); | |
3189 | ||
3190 | split = mast->bn->b_end; | |
3191 | mab_set_b_end(mast->bn, mast->l, mast->l->node); | |
3192 | mast->r->offset = mast->bn->b_end; | |
3193 | mab_set_b_end(mast->bn, mast->r, mast->r->node); | |
3194 | if (mast->bn->pivot[mast->bn->b_end - 1] == mas->max) | |
3195 | cp = false; | |
3196 | ||
3197 | if (cp) | |
3198 | mas_mab_cp(mas, split + skip, mt_slot_count(mas->node) - 1, | |
3199 | mast->bn, mast->bn->b_end); | |
3200 | ||
3201 | mast->bn->b_end--; | |
3202 | mast->bn->type = mte_node_type(mas->node); | |
3203 | } | |
3204 | ||
3205 | /* | |
3206 | * mast_split_data() - Split the data in the subtree state big node into regular | |
3207 | * nodes. | |
3208 | * @mast: The maple subtree state | |
3209 | * @mas: The maple state | |
3210 | * @split: The location to split the big node | |
3211 | */ | |
3212 | static inline void mast_split_data(struct maple_subtree_state *mast, | |
3213 | struct ma_state *mas, unsigned char split) | |
3214 | { | |
3215 | unsigned char p_slot; | |
3216 | ||
3217 | mab_mas_cp(mast->bn, 0, split, mast->l, true); | |
3218 | mte_set_pivot(mast->r->node, 0, mast->r->max); | |
3219 | mab_mas_cp(mast->bn, split + 1, mast->bn->b_end, mast->r, false); | |
3220 | mast->l->offset = mte_parent_slot(mas->node); | |
3221 | mast->l->max = mast->bn->pivot[split]; | |
3222 | mast->r->min = mast->l->max + 1; | |
3223 | if (mte_is_leaf(mas->node)) | |
3224 | return; | |
3225 | ||
3226 | p_slot = mast->orig_l->offset; | |
3227 | mas_set_split_parent(mast->orig_l, mast->l->node, mast->r->node, | |
3228 | &p_slot, split); | |
3229 | mas_set_split_parent(mast->orig_r, mast->l->node, mast->r->node, | |
3230 | &p_slot, split); | |
3231 | } | |
3232 | ||
3233 | /* | |
3234 | * mas_push_data() - Instead of splitting a node, it is beneficial to push the | |
3235 | * data to the right or left node if there is room. | |
3236 | * @mas: The maple state | |
3237 | * @height: The current height of the maple state | |
3238 | * @mast: The maple subtree state | |
3239 | * @left: Push left or not. | |
3240 | * | |
3241 | * Keeping the height of the tree low means faster lookups. | |
3242 | * | |
3243 | * Return: True if pushed, false otherwise. | |
3244 | */ | |
3245 | static inline bool mas_push_data(struct ma_state *mas, int height, | |
3246 | struct maple_subtree_state *mast, bool left) | |
3247 | { | |
3248 | unsigned char slot_total = mast->bn->b_end; | |
3249 | unsigned char end, space, split; | |
3250 | ||
3251 | MA_STATE(tmp_mas, mas->tree, mas->index, mas->last); | |
3252 | tmp_mas = *mas; | |
3253 | tmp_mas.depth = mast->l->depth; | |
3254 | ||
3255 | if (left && !mas_prev_sibling(&tmp_mas)) | |
3256 | return false; | |
3257 | else if (!left && !mas_next_sibling(&tmp_mas)) | |
3258 | return false; | |
3259 | ||
3260 | end = mas_data_end(&tmp_mas); | |
3261 | slot_total += end; | |
3262 | space = 2 * mt_slot_count(mas->node) - 2; | |
3263 | /* -2 instead of -1 to ensure there isn't a triple split */ | |
3264 | if (ma_is_leaf(mast->bn->type)) | |
3265 | space--; | |
3266 | ||
3267 | if (mas->max == ULONG_MAX) | |
3268 | space--; | |
3269 | ||
3270 | if (slot_total >= space) | |
3271 | return false; | |
3272 | ||
3273 | /* Get the data; Fill mast->bn */ | |
3274 | mast->bn->b_end++; | |
3275 | if (left) { | |
3276 | mab_shift_right(mast->bn, end + 1); | |
3277 | mas_mab_cp(&tmp_mas, 0, end, mast->bn, 0); | |
3278 | mast->bn->b_end = slot_total + 1; | |
3279 | } else { | |
3280 | mas_mab_cp(&tmp_mas, 0, end, mast->bn, mast->bn->b_end); | |
3281 | } | |
3282 | ||
3283 | /* Configure mast for splitting of mast->bn */ | |
3284 | split = mt_slots[mast->bn->type] - 2; | |
3285 | if (left) { | |
3286 | /* Switch mas to prev node */ | |
54a611b6 LH |
3287 | *mas = tmp_mas; |
3288 | /* Start using mast->l for the left side. */ | |
3289 | tmp_mas.node = mast->l->node; | |
3290 | *mast->l = tmp_mas; | |
3291 | } else { | |
54a611b6 LH |
3292 | tmp_mas.node = mast->r->node; |
3293 | *mast->r = tmp_mas; | |
3294 | split = slot_total - split; | |
3295 | } | |
3296 | split = mab_no_null_split(mast->bn, split, mt_slots[mast->bn->type]); | |
3297 | /* Update parent slot for split calculation. */ | |
3298 | if (left) | |
3299 | mast->orig_l->offset += end + 1; | |
3300 | ||
3301 | mast_split_data(mast, mas, split); | |
3302 | mast_fill_bnode(mast, mas, 2); | |
3303 | mas_split_final_node(mast, mas, height + 1); | |
3304 | return true; | |
3305 | } | |
3306 | ||
3307 | /* | |
3308 | * mas_split() - Split data that is too big for one node into two. | |
3309 | * @mas: The maple state | |
3310 | * @b_node: The maple big node | |
3311 | * Return: 1 on success, 0 on failure. | |
3312 | */ | |
3313 | static int mas_split(struct ma_state *mas, struct maple_big_node *b_node) | |
3314 | { | |
54a611b6 LH |
3315 | struct maple_subtree_state mast; |
3316 | int height = 0; | |
3317 | unsigned char mid_split, split = 0; | |
530f745c | 3318 | struct maple_enode *old; |
54a611b6 LH |
3319 | |
3320 | /* | |
3321 | * Splitting is handled differently from any other B-tree; the Maple | |
3322 | * Tree splits upwards. Splitting up means that the split operation | |
3323 | * occurs when the walk of the tree hits the leaves and not on the way | |
3324 | * down. The reason for splitting up is that it is impossible to know | |
3325 | * how much space will be needed until the leaf is (or leaves are) | |
3326 | * reached. Since overwriting data is allowed and a range could | |
3327 | * overwrite more than one range or result in changing one entry into 3 | |
3328 | * entries, it is impossible to know if a split is required until the | |
3329 | * data is examined. | |
3330 | * | |
3331 | * Splitting is a balancing act between keeping allocations to a minimum | |
3332 | * and avoiding a 'jitter' event where a tree is expanded to make room | |
3333 | * for an entry followed by a contraction when the entry is removed. To | |
3334 | * accomplish the balance, there are empty slots remaining in both left | |
3335 | * and right nodes after a split. | |
3336 | */ | |
3337 | MA_STATE(l_mas, mas->tree, mas->index, mas->last); | |
3338 | MA_STATE(r_mas, mas->tree, mas->index, mas->last); | |
3339 | MA_STATE(prev_l_mas, mas->tree, mas->index, mas->last); | |
3340 | MA_STATE(prev_r_mas, mas->tree, mas->index, mas->last); | |
54a611b6 LH |
3341 | |
3342 | trace_ma_op(__func__, mas); | |
3343 | mas->depth = mas_mt_height(mas); | |
3344 | /* Allocation failures will happen early. */ | |
3345 | mas_node_count(mas, 1 + mas->depth * 2); | |
3346 | if (mas_is_err(mas)) | |
3347 | return 0; | |
3348 | ||
3349 | mast.l = &l_mas; | |
3350 | mast.r = &r_mas; | |
3351 | mast.orig_l = &prev_l_mas; | |
3352 | mast.orig_r = &prev_r_mas; | |
54a611b6 LH |
3353 | mast.bn = b_node; |
3354 | ||
3355 | while (height++ <= mas->depth) { | |
3356 | if (mt_slots[b_node->type] > b_node->b_end) { | |
3357 | mas_split_final_node(&mast, mas, height); | |
3358 | break; | |
3359 | } | |
3360 | ||
3361 | l_mas = r_mas = *mas; | |
3362 | l_mas.node = mas_new_ma_node(mas, b_node); | |
3363 | r_mas.node = mas_new_ma_node(mas, b_node); | |
3364 | /* | |
3365 | * Another way that 'jitter' is avoided is to terminate a split up early if the | |
3366 | * left or right node has space to spare. This is referred to as "pushing left" | |
3367 | * or "pushing right" and is similar to the B* tree, except the nodes left or | |
3368 | * right can rarely be reused due to RCU, but the ripple upwards is halted which | |
3369 | * is a significant savings. | |
3370 | */ | |
3371 | /* Try to push left. */ | |
3372 | if (mas_push_data(mas, height, &mast, true)) | |
3373 | break; | |
54a611b6 LH |
3374 | /* Try to push right. */ |
3375 | if (mas_push_data(mas, height, &mast, false)) | |
3376 | break; | |
3377 | ||
3378 | split = mab_calc_split(mas, b_node, &mid_split, prev_l_mas.min); | |
3379 | mast_split_data(&mast, mas, split); | |
3380 | /* | |
3381 | * Usually correct, mab_mas_cp in the above call overwrites | |
3382 | * r->max. | |
3383 | */ | |
3384 | mast.r->max = mas->max; | |
3385 | mast_fill_bnode(&mast, mas, 1); | |
3386 | prev_l_mas = *mast.l; | |
3387 | prev_r_mas = *mast.r; | |
3388 | } | |
3389 | ||
3390 | /* Set the original node as dead */ | |
530f745c | 3391 | old = mas->node; |
54a611b6 | 3392 | mas->node = l_mas.node; |
530f745c | 3393 | mas_wmb_replace(mas, old); |
54a611b6 LH |
3394 | mtree_range_walk(mas); |
3395 | return 1; | |
3396 | } | |
3397 | ||
3398 | /* | |
3399 | * mas_reuse_node() - Reuse the node to store the data. | |
3400 | * @wr_mas: The maple write state | |
3401 | * @bn: The maple big node | |
3402 | * @end: The end of the data. | |
3403 | * | |
3404 | * Will always return false in RCU mode. | |
3405 | * | |
3406 | * Return: True if node was reused, false otherwise. | |
3407 | */ | |
3408 | static inline bool mas_reuse_node(struct ma_wr_state *wr_mas, | |
3409 | struct maple_big_node *bn, unsigned char end) | |
3410 | { | |
3411 | /* Need to be rcu safe. */ | |
3412 | if (mt_in_rcu(wr_mas->mas->tree)) | |
3413 | return false; | |
3414 | ||
3415 | if (end > bn->b_end) { | |
3416 | int clear = mt_slots[wr_mas->type] - bn->b_end; | |
3417 | ||
3418 | memset(wr_mas->slots + bn->b_end, 0, sizeof(void *) * clear--); | |
3419 | memset(wr_mas->pivots + bn->b_end, 0, sizeof(void *) * clear); | |
3420 | } | |
3421 | mab_mas_cp(bn, 0, bn->b_end, wr_mas->mas, false); | |
3422 | return true; | |
3423 | } | |
3424 | ||
3425 | /* | |
3426 | * mas_commit_b_node() - Commit the big node into the tree. | |
3427 | * @wr_mas: The maple write state | |
3428 | * @b_node: The maple big node | |
3429 | * @end: The end of the data. | |
3430 | */ | |
44081c77 | 3431 | static noinline_for_kasan int mas_commit_b_node(struct ma_wr_state *wr_mas, |
54a611b6 LH |
3432 | struct maple_big_node *b_node, unsigned char end) |
3433 | { | |
3434 | struct maple_node *node; | |
72bcf4aa | 3435 | struct maple_enode *old_enode; |
54a611b6 LH |
3436 | unsigned char b_end = b_node->b_end; |
3437 | enum maple_type b_type = b_node->type; | |
3438 | ||
72bcf4aa | 3439 | old_enode = wr_mas->mas->node; |
54a611b6 | 3440 | if ((b_end < mt_min_slots[b_type]) && |
72bcf4aa | 3441 | (!mte_is_root(old_enode)) && |
54a611b6 LH |
3442 | (mas_mt_height(wr_mas->mas) > 1)) |
3443 | return mas_rebalance(wr_mas->mas, b_node); | |
3444 | ||
3445 | if (b_end >= mt_slots[b_type]) | |
3446 | return mas_split(wr_mas->mas, b_node); | |
3447 | ||
3448 | if (mas_reuse_node(wr_mas, b_node, end)) | |
3449 | goto reuse_node; | |
3450 | ||
3451 | mas_node_count(wr_mas->mas, 1); | |
3452 | if (mas_is_err(wr_mas->mas)) | |
3453 | return 0; | |
3454 | ||
3455 | node = mas_pop_node(wr_mas->mas); | |
3456 | node->parent = mas_mn(wr_mas->mas)->parent; | |
3457 | wr_mas->mas->node = mt_mk_node(node, b_type); | |
7dc5ba62 | 3458 | mab_mas_cp(b_node, 0, b_end, wr_mas->mas, false); |
72bcf4aa | 3459 | mas_replace_node(wr_mas->mas, old_enode); |
54a611b6 LH |
3460 | reuse_node: |
3461 | mas_update_gap(wr_mas->mas); | |
31c532a8 | 3462 | wr_mas->mas->end = b_end; |
54a611b6 LH |
3463 | return 1; |
3464 | } | |
3465 | ||
3466 | /* | |
3467 | * mas_root_expand() - Expand a root to a node | |
3468 | * @mas: The maple state | |
3469 | * @entry: The entry to store into the tree | |
3470 | */ | |
3471 | static inline int mas_root_expand(struct ma_state *mas, void *entry) | |
3472 | { | |
3473 | void *contents = mas_root_locked(mas); | |
3474 | enum maple_type type = maple_leaf_64; | |
3475 | struct maple_node *node; | |
3476 | void __rcu **slots; | |
3477 | unsigned long *pivots; | |
3478 | int slot = 0; | |
3479 | ||
3480 | mas_node_count(mas, 1); | |
3481 | if (unlikely(mas_is_err(mas))) | |
3482 | return 0; | |
3483 | ||
3484 | node = mas_pop_node(mas); | |
3485 | pivots = ma_pivots(node, type); | |
3486 | slots = ma_slots(node, type); | |
4ffc2ee2 | 3487 | node->parent = ma_parent_ptr(mas_tree_parent(mas)); |
54a611b6 | 3488 | mas->node = mt_mk_node(node, type); |
067311d3 | 3489 | mas->status = ma_active; |
54a611b6 LH |
3490 | |
3491 | if (mas->index) { | |
3492 | if (contents) { | |
3493 | rcu_assign_pointer(slots[slot], contents); | |
3494 | if (likely(mas->index > 1)) | |
3495 | slot++; | |
3496 | } | |
3497 | pivots[slot++] = mas->index - 1; | |
3498 | } | |
3499 | ||
3500 | rcu_assign_pointer(slots[slot], entry); | |
3501 | mas->offset = slot; | |
3502 | pivots[slot] = mas->last; | |
3503 | if (mas->last != ULONG_MAX) | |
3c769fd8 PZ |
3504 | pivots[++slot] = ULONG_MAX; |
3505 | ||
54a611b6 LH |
3506 | mas->depth = 1; |
3507 | mas_set_height(mas); | |
c45ea315 | 3508 | ma_set_meta(node, maple_leaf_64, 0, slot); |
54a611b6 LH |
3509 | /* swap the new root into the tree */ |
3510 | rcu_assign_pointer(mas->tree->ma_root, mte_mk_root(mas->node)); | |
54a611b6 LH |
3511 | return slot; |
3512 | } | |
3513 | ||
3514 | static inline void mas_store_root(struct ma_state *mas, void *entry) | |
3515 | { | |
3516 | if (likely((mas->last != 0) || (mas->index != 0))) | |
3517 | mas_root_expand(mas, entry); | |
3518 | else if (((unsigned long) (entry) & 3) == 2) | |
3519 | mas_root_expand(mas, entry); | |
3520 | else { | |
3521 | rcu_assign_pointer(mas->tree->ma_root, entry); | |
067311d3 | 3522 | mas->status = ma_start; |
54a611b6 LH |
3523 | } |
3524 | } | |
3525 | ||
3526 | /* | |
3527 | * mas_is_span_wr() - Check if the write needs to be treated as a write that | |
3528 | * spans the node. | |
3529 | * @mas: The maple state | |
3530 | * @piv: The pivot value being written | |
3531 | * @type: The maple node type | |
3532 | * @entry: The data to write | |
3533 | * | |
3534 | * Spanning writes are writes that start in one node and end in another OR if | |
3535 | * the write of a %NULL will cause the node to end with a %NULL. | |
3536 | * | |
3537 | * Return: True if this is a spanning write, false otherwise. | |
3538 | */ | |
3539 | static bool mas_is_span_wr(struct ma_wr_state *wr_mas) | |
3540 | { | |
bc147f0f | 3541 | unsigned long max = wr_mas->r_max; |
54a611b6 | 3542 | unsigned long last = wr_mas->mas->last; |
54a611b6 LH |
3543 | enum maple_type type = wr_mas->type; |
3544 | void *entry = wr_mas->entry; | |
3545 | ||
bc147f0f PZ |
3546 | /* Contained in this pivot, fast path */ |
3547 | if (last < max) | |
54a611b6 LH |
3548 | return false; |
3549 | ||
bc147f0f PZ |
3550 | if (ma_is_leaf(type)) { |
3551 | max = wr_mas->mas->max; | |
54a611b6 LH |
3552 | if (last < max) |
3553 | return false; | |
bc147f0f | 3554 | } |
54a611b6 | 3555 | |
bc147f0f | 3556 | if (last == max) { |
54a611b6 | 3557 | /* |
bc147f0f PZ |
3558 | * The last entry of leaf node cannot be NULL unless it is the |
3559 | * rightmost node (writing ULONG_MAX), otherwise it spans slots. | |
54a611b6 | 3560 | */ |
bc147f0f | 3561 | if (entry || last == ULONG_MAX) |
54a611b6 LH |
3562 | return false; |
3563 | } | |
3564 | ||
bc147f0f | 3565 | trace_ma_write(__func__, wr_mas->mas, wr_mas->r_max, entry); |
54a611b6 LH |
3566 | return true; |
3567 | } | |
3568 | ||
3569 | static inline void mas_wr_walk_descend(struct ma_wr_state *wr_mas) | |
3570 | { | |
54a611b6 LH |
3571 | wr_mas->type = mte_node_type(wr_mas->mas->node); |
3572 | mas_wr_node_walk(wr_mas); | |
3573 | wr_mas->slots = ma_slots(wr_mas->node, wr_mas->type); | |
3574 | } | |
3575 | ||
3576 | static inline void mas_wr_walk_traverse(struct ma_wr_state *wr_mas) | |
3577 | { | |
3578 | wr_mas->mas->max = wr_mas->r_max; | |
3579 | wr_mas->mas->min = wr_mas->r_min; | |
3580 | wr_mas->mas->node = wr_mas->content; | |
3581 | wr_mas->mas->offset = 0; | |
9bbba563 | 3582 | wr_mas->mas->depth++; |
54a611b6 LH |
3583 | } |
3584 | /* | |
3585 | * mas_wr_walk() - Walk the tree for a write. | |
3586 | * @wr_mas: The maple write state | |
3587 | * | |
3588 | * Uses mas_slot_locked() and does not need to worry about dead nodes. | |
3589 | * | |
3590 | * Return: True if it's contained in a node, false on spanning write. | |
3591 | */ | |
3592 | static bool mas_wr_walk(struct ma_wr_state *wr_mas) | |
3593 | { | |
3594 | struct ma_state *mas = wr_mas->mas; | |
3595 | ||
3596 | while (true) { | |
3597 | mas_wr_walk_descend(wr_mas); | |
3598 | if (unlikely(mas_is_span_wr(wr_mas))) | |
3599 | return false; | |
3600 | ||
3601 | wr_mas->content = mas_slot_locked(mas, wr_mas->slots, | |
3602 | mas->offset); | |
3603 | if (ma_is_leaf(wr_mas->type)) | |
3604 | return true; | |
3605 | ||
3606 | mas_wr_walk_traverse(wr_mas); | |
3607 | } | |
3608 | ||
3609 | return true; | |
3610 | } | |
3611 | ||
3612 | static bool mas_wr_walk_index(struct ma_wr_state *wr_mas) | |
3613 | { | |
3614 | struct ma_state *mas = wr_mas->mas; | |
3615 | ||
3616 | while (true) { | |
3617 | mas_wr_walk_descend(wr_mas); | |
3618 | wr_mas->content = mas_slot_locked(mas, wr_mas->slots, | |
3619 | mas->offset); | |
3620 | if (ma_is_leaf(wr_mas->type)) | |
3621 | return true; | |
3622 | mas_wr_walk_traverse(wr_mas); | |
3623 | ||
3624 | } | |
3625 | return true; | |
3626 | } | |
3627 | /* | |
3628 | * mas_extend_spanning_null() - Extend a store of a %NULL to include surrounding %NULLs. | |
3629 | * @l_wr_mas: The left maple write state | |
3630 | * @r_wr_mas: The right maple write state | |
3631 | */ | |
3632 | static inline void mas_extend_spanning_null(struct ma_wr_state *l_wr_mas, | |
3633 | struct ma_wr_state *r_wr_mas) | |
3634 | { | |
3635 | struct ma_state *r_mas = r_wr_mas->mas; | |
3636 | struct ma_state *l_mas = l_wr_mas->mas; | |
3637 | unsigned char l_slot; | |
3638 | ||
3639 | l_slot = l_mas->offset; | |
3640 | if (!l_wr_mas->content) | |
3641 | l_mas->index = l_wr_mas->r_min; | |
3642 | ||
3643 | if ((l_mas->index == l_wr_mas->r_min) && | |
3644 | (l_slot && | |
3645 | !mas_slot_locked(l_mas, l_wr_mas->slots, l_slot - 1))) { | |
3646 | if (l_slot > 1) | |
3647 | l_mas->index = l_wr_mas->pivots[l_slot - 2] + 1; | |
3648 | else | |
3649 | l_mas->index = l_mas->min; | |
3650 | ||
3651 | l_mas->offset = l_slot - 1; | |
3652 | } | |
3653 | ||
3654 | if (!r_wr_mas->content) { | |
3655 | if (r_mas->last < r_wr_mas->r_max) | |
3656 | r_mas->last = r_wr_mas->r_max; | |
3657 | r_mas->offset++; | |
3658 | } else if ((r_mas->last == r_wr_mas->r_max) && | |
3659 | (r_mas->last < r_mas->max) && | |
3660 | !mas_slot_locked(r_mas, r_wr_mas->slots, r_mas->offset + 1)) { | |
3661 | r_mas->last = mas_safe_pivot(r_mas, r_wr_mas->pivots, | |
3662 | r_wr_mas->type, r_mas->offset + 1); | |
3663 | r_mas->offset++; | |
3664 | } | |
3665 | } | |
3666 | ||
3667 | static inline void *mas_state_walk(struct ma_state *mas) | |
3668 | { | |
3669 | void *entry; | |
3670 | ||
3671 | entry = mas_start(mas); | |
3672 | if (mas_is_none(mas)) | |
3673 | return NULL; | |
3674 | ||
3675 | if (mas_is_ptr(mas)) | |
3676 | return entry; | |
3677 | ||
3678 | return mtree_range_walk(mas); | |
3679 | } | |
3680 | ||
3681 | /* | |
3682 | * mtree_lookup_walk() - Internal quick lookup that does not keep maple state up | |
3683 | * to date. | |
3684 | * | |
3685 | * @mas: The maple state. | |
3686 | * | |
3687 | * Note: Leaves mas in undesirable state. | |
3688 | * Return: The entry for @mas->index or %NULL on dead node. | |
3689 | */ | |
3690 | static inline void *mtree_lookup_walk(struct ma_state *mas) | |
3691 | { | |
3692 | unsigned long *pivots; | |
3693 | unsigned char offset; | |
3694 | struct maple_node *node; | |
3695 | struct maple_enode *next; | |
3696 | enum maple_type type; | |
3697 | void __rcu **slots; | |
3698 | unsigned char end; | |
54a611b6 LH |
3699 | |
3700 | next = mas->node; | |
54a611b6 | 3701 | do { |
54a611b6 LH |
3702 | node = mte_to_node(next); |
3703 | type = mte_node_type(next); | |
3704 | pivots = ma_pivots(node, type); | |
24662dec LH |
3705 | end = mt_pivots[type]; |
3706 | offset = 0; | |
54a611b6 | 3707 | do { |
24662dec | 3708 | if (pivots[offset] >= mas->index) |
ec07967d | 3709 | break; |
ec07967d | 3710 | } while (++offset < end); |
54a611b6 | 3711 | |
54a611b6 LH |
3712 | slots = ma_slots(node, type); |
3713 | next = mt_slot(mas->tree, slots, offset); | |
3714 | if (unlikely(ma_dead_node(node))) | |
3715 | goto dead_node; | |
3716 | } while (!ma_is_leaf(type)); | |
3717 | ||
831978e3 | 3718 | return (void *)next; |
54a611b6 LH |
3719 | |
3720 | dead_node: | |
3721 | mas_reset(mas); | |
3722 | return NULL; | |
3723 | } | |
3724 | ||
530f745c | 3725 | static void mte_destroy_walk(struct maple_enode *, struct maple_tree *); |
54a611b6 LH |
3726 | /* |
3727 | * mas_new_root() - Create a new root node that only contains the entry passed | |
3728 | * in. | |
3729 | * @mas: The maple state | |
3730 | * @entry: The entry to store. | |
3731 | * | |
3732 | * Only valid when the index == 0 and the last == ULONG_MAX | |
3733 | * | |
3734 | * Return 0 on error, 1 on success. | |
3735 | */ | |
3736 | static inline int mas_new_root(struct ma_state *mas, void *entry) | |
3737 | { | |
3738 | struct maple_enode *root = mas_root_locked(mas); | |
3739 | enum maple_type type = maple_leaf_64; | |
3740 | struct maple_node *node; | |
3741 | void __rcu **slots; | |
3742 | unsigned long *pivots; | |
3743 | ||
3744 | if (!entry && !mas->index && mas->last == ULONG_MAX) { | |
3745 | mas->depth = 0; | |
3746 | mas_set_height(mas); | |
3747 | rcu_assign_pointer(mas->tree->ma_root, entry); | |
067311d3 | 3748 | mas->status = ma_start; |
54a611b6 LH |
3749 | goto done; |
3750 | } | |
3751 | ||
3752 | mas_node_count(mas, 1); | |
3753 | if (mas_is_err(mas)) | |
3754 | return 0; | |
3755 | ||
3756 | node = mas_pop_node(mas); | |
3757 | pivots = ma_pivots(node, type); | |
3758 | slots = ma_slots(node, type); | |
4ffc2ee2 | 3759 | node->parent = ma_parent_ptr(mas_tree_parent(mas)); |
54a611b6 | 3760 | mas->node = mt_mk_node(node, type); |
067311d3 | 3761 | mas->status = ma_active; |
54a611b6 LH |
3762 | rcu_assign_pointer(slots[0], entry); |
3763 | pivots[0] = mas->last; | |
3764 | mas->depth = 1; | |
3765 | mas_set_height(mas); | |
3766 | rcu_assign_pointer(mas->tree->ma_root, mte_mk_root(mas->node)); | |
3767 | ||
3768 | done: | |
3769 | if (xa_is_node(root)) | |
3770 | mte_destroy_walk(root, mas->tree); | |
3771 | ||
3772 | return 1; | |
3773 | } | |
3774 | /* | |
3775 | * mas_wr_spanning_store() - Create a subtree with the store operation completed | |
3776 | * and new nodes where necessary, then place the sub-tree in the actual tree. | |
3777 | * Note that mas is expected to point to the node which caused the store to | |
3778 | * span. | |
3779 | * @wr_mas: The maple write state | |
3780 | * | |
3781 | * Return: 0 on error, positive on success. | |
3782 | */ | |
3783 | static inline int mas_wr_spanning_store(struct ma_wr_state *wr_mas) | |
3784 | { | |
3785 | struct maple_subtree_state mast; | |
3786 | struct maple_big_node b_node; | |
3787 | struct ma_state *mas; | |
3788 | unsigned char height; | |
3789 | ||
3790 | /* Left and Right side of spanning store */ | |
3791 | MA_STATE(l_mas, NULL, 0, 0); | |
3792 | MA_STATE(r_mas, NULL, 0, 0); | |
54a611b6 LH |
3793 | MA_WR_STATE(r_wr_mas, &r_mas, wr_mas->entry); |
3794 | MA_WR_STATE(l_wr_mas, &l_mas, wr_mas->entry); | |
3795 | ||
3796 | /* | |
3797 | * A store operation that spans multiple nodes is called a spanning | |
3798 | * store and is handled early in the store call stack by the function | |
3799 | * mas_is_span_wr(). When a spanning store is identified, the maple | |
3800 | * state is duplicated. The first maple state walks the left tree path | |
3801 | * to ``index``, the duplicate walks the right tree path to ``last``. | |
3802 | * The data in the two nodes are combined into a single node, two nodes, | |
3803 | * or possibly three nodes (see the 3-way split above). A ``NULL`` | |
3804 | * written to the last entry of a node is considered a spanning store as | |
3805 | * a rebalance is required for the operation to complete and an overflow | |
3806 | * of data may happen. | |
3807 | */ | |
3808 | mas = wr_mas->mas; | |
3809 | trace_ma_op(__func__, mas); | |
3810 | ||
3811 | if (unlikely(!mas->index && mas->last == ULONG_MAX)) | |
3812 | return mas_new_root(mas, wr_mas->entry); | |
3813 | /* | |
3814 | * Node rebalancing may occur due to this store, so there may be three new | |
3815 | * entries per level plus a new root. | |
3816 | */ | |
3817 | height = mas_mt_height(mas); | |
3818 | mas_node_count(mas, 1 + height * 3); | |
3819 | if (mas_is_err(mas)) | |
3820 | return 0; | |
3821 | ||
3822 | /* | |
3823 | * Set up right side. Need to get to the next offset after the spanning | |
3824 | * store to ensure it's not NULL and to combine both the next node and | |
3825 | * the node with the start together. | |
3826 | */ | |
3827 | r_mas = *mas; | |
3828 | /* Avoid overflow, walk to next slot in the tree. */ | |
3829 | if (r_mas.last + 1) | |
3830 | r_mas.last++; | |
3831 | ||
3832 | r_mas.index = r_mas.last; | |
3833 | mas_wr_walk_index(&r_wr_mas); | |
3834 | r_mas.last = r_mas.index = mas->last; | |
3835 | ||
3836 | /* Set up left side. */ | |
3837 | l_mas = *mas; | |
3838 | mas_wr_walk_index(&l_wr_mas); | |
3839 | ||
3840 | if (!wr_mas->entry) { | |
3841 | mas_extend_spanning_null(&l_wr_mas, &r_wr_mas); | |
3842 | mas->offset = l_mas.offset; | |
3843 | mas->index = l_mas.index; | |
3844 | mas->last = l_mas.last = r_mas.last; | |
3845 | } | |
3846 | ||
3847 | /* expanding NULLs may make this cover the entire range */ | |
3848 | if (!l_mas.index && r_mas.last == ULONG_MAX) { | |
3849 | mas_set_range(mas, 0, ULONG_MAX); | |
3850 | return mas_new_root(mas, wr_mas->entry); | |
3851 | } | |
3852 | ||
3853 | memset(&b_node, 0, sizeof(struct maple_big_node)); | |
3854 | /* Copy l_mas and store the value in b_node. */ | |
0de56e38 | 3855 | mas_store_b_node(&l_wr_mas, &b_node, l_mas.end); |
54a611b6 | 3856 | /* Copy r_mas into b_node. */ |
0de56e38 LH |
3857 | if (r_mas.offset <= r_mas.end) |
3858 | mas_mab_cp(&r_mas, r_mas.offset, r_mas.end, | |
54a611b6 LH |
3859 | &b_node, b_node.b_end + 1); |
3860 | else | |
3861 | b_node.b_end++; | |
3862 | ||
3863 | /* Stop spanning searches by searching for just index. */ | |
3864 | l_mas.index = l_mas.last = mas->index; | |
3865 | ||
3866 | mast.bn = &b_node; | |
3867 | mast.orig_l = &l_mas; | |
3868 | mast.orig_r = &r_mas; | |
3869 | /* Combine l_mas and r_mas and split them up evenly again. */ | |
3870 | return mas_spanning_rebalance(mas, &mast, height + 1); | |
3871 | } | |
3872 | ||
3873 | /* | |
3874 | * mas_wr_node_store() - Attempt to store the value in a node | |
3875 | * @wr_mas: The maple write state | |
3876 | * | |
3877 | * Attempts to reuse the node, but may allocate. | |
3878 | * | |
3879 | * Return: True if stored, false otherwise | |
3880 | */ | |
7a03ae39 PZ |
3881 | static inline bool mas_wr_node_store(struct ma_wr_state *wr_mas, |
3882 | unsigned char new_end) | |
54a611b6 LH |
3883 | { |
3884 | struct ma_state *mas = wr_mas->mas; | |
3885 | void __rcu **dst_slots; | |
3886 | unsigned long *dst_pivots; | |
7a03ae39 | 3887 | unsigned char dst_offset, offset_end = wr_mas->offset_end; |
54a611b6 | 3888 | struct maple_node reuse, *newnode; |
7a03ae39 | 3889 | unsigned char copy_size, node_pivots = mt_pivots[wr_mas->type]; |
54a611b6 LH |
3890 | bool in_rcu = mt_in_rcu(mas->tree); |
3891 | ||
7a03ae39 | 3892 | /* Check if there is enough data. The room is enough. */ |
54a611b6 LH |
3893 | if (!mte_is_root(mas->node) && (new_end <= mt_min_slots[wr_mas->type]) && |
3894 | !(mas->mas_flags & MA_STATE_BULK)) | |
3895 | return false; | |
3896 | ||
7a03ae39 PZ |
3897 | if (mas->last == wr_mas->end_piv) |
3898 | offset_end++; /* don't copy this offset */ | |
3899 | else if (unlikely(wr_mas->r_max == ULONG_MAX)) | |
0de56e38 | 3900 | mas_bulk_rebalance(mas, mas->end, wr_mas->type); |
7a03ae39 | 3901 | |
54a611b6 LH |
3902 | /* set up node. */ |
3903 | if (in_rcu) { | |
3904 | mas_node_count(mas, 1); | |
3905 | if (mas_is_err(mas)) | |
3906 | return false; | |
3907 | ||
3908 | newnode = mas_pop_node(mas); | |
3909 | } else { | |
3910 | memset(&reuse, 0, sizeof(struct maple_node)); | |
3911 | newnode = &reuse; | |
3912 | } | |
3913 | ||
3914 | newnode->parent = mas_mn(mas)->parent; | |
3915 | dst_pivots = ma_pivots(newnode, wr_mas->type); | |
3916 | dst_slots = ma_slots(newnode, wr_mas->type); | |
3917 | /* Copy from start to insert point */ | |
7a03ae39 PZ |
3918 | memcpy(dst_pivots, wr_mas->pivots, sizeof(unsigned long) * mas->offset); |
3919 | memcpy(dst_slots, wr_mas->slots, sizeof(void *) * mas->offset); | |
54a611b6 LH |
3920 | |
3921 | /* Handle insert of new range starting after old range */ | |
3922 | if (wr_mas->r_min < mas->index) { | |
7a03ae39 PZ |
3923 | rcu_assign_pointer(dst_slots[mas->offset], wr_mas->content); |
3924 | dst_pivots[mas->offset++] = mas->index - 1; | |
54a611b6 LH |
3925 | } |
3926 | ||
3927 | /* Store the new entry and range end. */ | |
7a03ae39 PZ |
3928 | if (mas->offset < node_pivots) |
3929 | dst_pivots[mas->offset] = mas->last; | |
3930 | rcu_assign_pointer(dst_slots[mas->offset], wr_mas->entry); | |
54a611b6 LH |
3931 | |
3932 | /* | |
3933 | * this range wrote to the end of the node or it overwrote the rest of | |
3934 | * the data | |
3935 | */ | |
0de56e38 | 3936 | if (offset_end > mas->end) |
54a611b6 | 3937 | goto done; |
54a611b6 | 3938 | |
7a03ae39 | 3939 | dst_offset = mas->offset + 1; |
54a611b6 | 3940 | /* Copy to the end of node if necessary. */ |
0de56e38 | 3941 | copy_size = mas->end - offset_end + 1; |
7a03ae39 | 3942 | memcpy(dst_slots + dst_offset, wr_mas->slots + offset_end, |
54a611b6 | 3943 | sizeof(void *) * copy_size); |
7a03ae39 PZ |
3944 | memcpy(dst_pivots + dst_offset, wr_mas->pivots + offset_end, |
3945 | sizeof(unsigned long) * (copy_size - 1)); | |
54a611b6 | 3946 | |
7a03ae39 | 3947 | if (new_end < node_pivots) |
54a611b6 LH |
3948 | dst_pivots[new_end] = mas->max; |
3949 | ||
3950 | done: | |
330018fe | 3951 | mas_leaf_set_meta(newnode, maple_leaf_64, new_end); |
54a611b6 | 3952 | if (in_rcu) { |
72bcf4aa LH |
3953 | struct maple_enode *old_enode = mas->node; |
3954 | ||
54a611b6 | 3955 | mas->node = mt_mk_node(newnode, wr_mas->type); |
72bcf4aa | 3956 | mas_replace_node(mas, old_enode); |
54a611b6 LH |
3957 | } else { |
3958 | memcpy(wr_mas->node, newnode, sizeof(struct maple_node)); | |
3959 | } | |
3960 | trace_ma_write(__func__, mas, 0, wr_mas->entry); | |
3961 | mas_update_gap(mas); | |
31c532a8 | 3962 | mas->end = new_end; |
54a611b6 LH |
3963 | return true; |
3964 | } | |
3965 | ||
3966 | /* | |
3967 | * mas_wr_slot_store: Attempt to store a value in a slot. | |
3968 | * @wr_mas: the maple write state | |
3969 | * | |
3970 | * Return: True if stored, false otherwise | |
3971 | */ | |
3972 | static inline bool mas_wr_slot_store(struct ma_wr_state *wr_mas) | |
3973 | { | |
3974 | struct ma_state *mas = wr_mas->mas; | |
54a611b6 | 3975 | unsigned char offset = mas->offset; |
64891ba3 | 3976 | void __rcu **slots = wr_mas->slots; |
e6d1ffd6 | 3977 | bool gap = false; |
54a611b6 | 3978 | |
64891ba3 PZ |
3979 | gap |= !mt_slot_locked(mas->tree, slots, offset); |
3980 | gap |= !mt_slot_locked(mas->tree, slots, offset + 1); | |
54a611b6 | 3981 | |
64891ba3 PZ |
3982 | if (wr_mas->offset_end - offset == 1) { |
3983 | if (mas->index == wr_mas->r_min) { | |
3984 | /* Overwriting the range and a part of the next one */ | |
3985 | rcu_assign_pointer(slots[offset], wr_mas->entry); | |
3986 | wr_mas->pivots[offset] = mas->last; | |
3987 | } else { | |
3988 | /* Overwriting a part of the range and the next one */ | |
3989 | rcu_assign_pointer(slots[offset + 1], wr_mas->entry); | |
3990 | wr_mas->pivots[offset] = mas->index - 1; | |
3991 | mas->offset++; /* Keep mas accurate. */ | |
3992 | } | |
3993 | } else if (!mt_in_rcu(mas->tree)) { | |
3994 | /* | |
3995 | * Expand the range, only partially overwriting the previous and | |
3996 | * next ranges | |
3997 | */ | |
3998 | gap |= !mt_slot_locked(mas->tree, slots, offset + 2); | |
3999 | rcu_assign_pointer(slots[offset + 1], wr_mas->entry); | |
e6d1ffd6 | 4000 | wr_mas->pivots[offset] = mas->index - 1; |
64891ba3 | 4001 | wr_mas->pivots[offset + 1] = mas->last; |
e6d1ffd6 | 4002 | mas->offset++; /* Keep mas accurate. */ |
64891ba3 PZ |
4003 | } else { |
4004 | return false; | |
54a611b6 LH |
4005 | } |
4006 | ||
54a611b6 | 4007 | trace_ma_write(__func__, mas, 0, wr_mas->entry); |
e6d1ffd6 PZ |
4008 | /* |
4009 | * Only update gap when the new entry is empty or there is an empty | |
4010 | * entry in the original two ranges. | |
4011 | */ | |
4012 | if (!wr_mas->entry || gap) | |
4013 | mas_update_gap(mas); | |
4014 | ||
54a611b6 LH |
4015 | return true; |
4016 | } | |
4017 | ||
54a611b6 LH |
4018 | static inline void mas_wr_extend_null(struct ma_wr_state *wr_mas) |
4019 | { | |
4020 | struct ma_state *mas = wr_mas->mas; | |
4021 | ||
8c995a63 PZ |
4022 | if (!wr_mas->slots[wr_mas->offset_end]) { |
4023 | /* If this one is null, the next and prev are not */ | |
54a611b6 | 4024 | mas->last = wr_mas->end_piv; |
8c995a63 PZ |
4025 | } else { |
4026 | /* Check next slot(s) if we are overwriting the end */ | |
4027 | if ((mas->last == wr_mas->end_piv) && | |
0de56e38 | 4028 | (mas->end != wr_mas->offset_end) && |
8c995a63 PZ |
4029 | !wr_mas->slots[wr_mas->offset_end + 1]) { |
4030 | wr_mas->offset_end++; | |
0de56e38 | 4031 | if (wr_mas->offset_end == mas->end) |
8c995a63 PZ |
4032 | mas->last = mas->max; |
4033 | else | |
4034 | mas->last = wr_mas->pivots[wr_mas->offset_end]; | |
4035 | wr_mas->end_piv = mas->last; | |
4036 | } | |
54a611b6 LH |
4037 | } |
4038 | ||
4039 | if (!wr_mas->content) { | |
4040 | /* If this one is null, the next and prev are not */ | |
4041 | mas->index = wr_mas->r_min; | |
4042 | } else { | |
4043 | /* Check prev slot if we are overwriting the start */ | |
4044 | if (mas->index == wr_mas->r_min && mas->offset && | |
4045 | !wr_mas->slots[mas->offset - 1]) { | |
4046 | mas->offset--; | |
4047 | wr_mas->r_min = mas->index = | |
4048 | mas_safe_min(mas, wr_mas->pivots, mas->offset); | |
4049 | wr_mas->r_max = wr_mas->pivots[mas->offset]; | |
4050 | } | |
4051 | } | |
4052 | } | |
4053 | ||
a7496ad5 LH |
4054 | static inline void mas_wr_end_piv(struct ma_wr_state *wr_mas) |
4055 | { | |
0de56e38 | 4056 | while ((wr_mas->offset_end < wr_mas->mas->end) && |
a7496ad5 LH |
4057 | (wr_mas->mas->last > wr_mas->pivots[wr_mas->offset_end])) |
4058 | wr_mas->offset_end++; | |
4059 | ||
0de56e38 | 4060 | if (wr_mas->offset_end < wr_mas->mas->end) |
a7496ad5 LH |
4061 | wr_mas->end_piv = wr_mas->pivots[wr_mas->offset_end]; |
4062 | else | |
4063 | wr_mas->end_piv = wr_mas->mas->max; | |
4064 | ||
4065 | if (!wr_mas->entry) | |
4066 | mas_wr_extend_null(wr_mas); | |
4067 | } | |
4068 | ||
c6fc9e4a PZ |
4069 | static inline unsigned char mas_wr_new_end(struct ma_wr_state *wr_mas) |
4070 | { | |
4071 | struct ma_state *mas = wr_mas->mas; | |
0de56e38 | 4072 | unsigned char new_end = mas->end + 2; |
c6fc9e4a PZ |
4073 | |
4074 | new_end -= wr_mas->offset_end - mas->offset; | |
4075 | if (wr_mas->r_min == mas->index) | |
4076 | new_end--; | |
4077 | ||
4078 | if (wr_mas->end_piv == mas->last) | |
4079 | new_end--; | |
4080 | ||
4081 | return new_end; | |
4082 | } | |
4083 | ||
2e1da329 PZ |
4084 | /* |
4085 | * mas_wr_append: Attempt to append | |
4086 | * @wr_mas: the maple write state | |
432af5c9 | 4087 | * @new_end: The end of the node after the modification |
2e1da329 | 4088 | * |
cfeb6ae8 LH |
4089 | * This is currently unsafe in rcu mode since the end of the node may be cached |
4090 | * by readers while the node contents may be updated which could result in | |
4091 | * inaccurate information. | |
4092 | * | |
2e1da329 PZ |
4093 | * Return: True if appended, false otherwise |
4094 | */ | |
23e9dde0 | 4095 | static inline bool mas_wr_append(struct ma_wr_state *wr_mas, |
432af5c9 | 4096 | unsigned char new_end) |
54a611b6 | 4097 | { |
432af5c9 LH |
4098 | struct ma_state *mas; |
4099 | void __rcu **slots; | |
4100 | unsigned char end; | |
54a611b6 | 4101 | |
432af5c9 | 4102 | mas = wr_mas->mas; |
cfeb6ae8 LH |
4103 | if (mt_in_rcu(mas->tree)) |
4104 | return false; | |
4105 | ||
0de56e38 | 4106 | end = mas->end; |
432af5c9 LH |
4107 | if (mas->offset != end) |
4108 | return false; | |
4109 | ||
4110 | if (new_end < mt_pivots[wr_mas->type]) { | |
2e1da329 | 4111 | wr_mas->pivots[new_end] = wr_mas->pivots[end]; |
432af5c9 | 4112 | ma_set_meta(wr_mas->node, wr_mas->type, 0, new_end); |
2e1da329 | 4113 | } |
54a611b6 | 4114 | |
432af5c9 LH |
4115 | slots = wr_mas->slots; |
4116 | if (new_end == end + 1) { | |
23e9dde0 PZ |
4117 | if (mas->last == wr_mas->r_max) { |
4118 | /* Append to end of range */ | |
432af5c9 | 4119 | rcu_assign_pointer(slots[new_end], wr_mas->entry); |
23e9dde0 PZ |
4120 | wr_mas->pivots[end] = mas->index - 1; |
4121 | mas->offset = new_end; | |
4122 | } else { | |
4123 | /* Append to start of range */ | |
432af5c9 | 4124 | rcu_assign_pointer(slots[new_end], wr_mas->content); |
23e9dde0 | 4125 | wr_mas->pivots[end] = mas->last; |
432af5c9 | 4126 | rcu_assign_pointer(slots[end], wr_mas->entry); |
23e9dde0 | 4127 | } |
2e1da329 | 4128 | } else { |
23e9dde0 | 4129 | /* Append to the range without touching any boundaries. */ |
432af5c9 | 4130 | rcu_assign_pointer(slots[new_end], wr_mas->content); |
23e9dde0 | 4131 | wr_mas->pivots[end + 1] = mas->last; |
432af5c9 | 4132 | rcu_assign_pointer(slots[end + 1], wr_mas->entry); |
23e9dde0 PZ |
4133 | wr_mas->pivots[end] = mas->index - 1; |
4134 | mas->offset = end + 1; | |
54a611b6 LH |
4135 | } |
4136 | ||
2e1da329 PZ |
4137 | if (!wr_mas->content || !wr_mas->entry) |
4138 | mas_update_gap(mas); | |
4139 | ||
31c532a8 | 4140 | mas->end = new_end; |
432af5c9 | 4141 | trace_ma_write(__func__, mas, new_end, wr_mas->entry); |
2e1da329 | 4142 | return true; |
54a611b6 LH |
4143 | } |
4144 | ||
4145 | /* | |
4146 | * mas_wr_bnode() - Slow path for a modification. | |
4147 | * @wr_mas: The write maple state | |
4148 | * | |
4149 | * This is where split, rebalance end up. | |
4150 | */ | |
4151 | static void mas_wr_bnode(struct ma_wr_state *wr_mas) | |
4152 | { | |
4153 | struct maple_big_node b_node; | |
4154 | ||
4155 | trace_ma_write(__func__, wr_mas->mas, 0, wr_mas->entry); | |
4156 | memset(&b_node, 0, sizeof(struct maple_big_node)); | |
4157 | mas_store_b_node(wr_mas, &b_node, wr_mas->offset_end); | |
0de56e38 | 4158 | mas_commit_b_node(wr_mas, &b_node, wr_mas->mas->end); |
54a611b6 LH |
4159 | } |
4160 | ||
4161 | static inline void mas_wr_modify(struct ma_wr_state *wr_mas) | |
4162 | { | |
54a611b6 | 4163 | struct ma_state *mas = wr_mas->mas; |
c6fc9e4a | 4164 | unsigned char new_end; |
54a611b6 LH |
4165 | |
4166 | /* Direct replacement */ | |
4167 | if (wr_mas->r_min == mas->index && wr_mas->r_max == mas->last) { | |
4168 | rcu_assign_pointer(wr_mas->slots[mas->offset], wr_mas->entry); | |
4169 | if (!!wr_mas->entry ^ !!wr_mas->content) | |
4170 | mas_update_gap(mas); | |
4171 | return; | |
4172 | } | |
4173 | ||
c6fc9e4a PZ |
4174 | /* |
4175 | * new_end exceeds the size of the maple node and cannot enter the fast | |
4176 | * path. | |
4177 | */ | |
4178 | new_end = mas_wr_new_end(wr_mas); | |
4179 | if (new_end >= mt_slots[wr_mas->type]) | |
54a611b6 LH |
4180 | goto slow_path; |
4181 | ||
2e1da329 | 4182 | /* Attempt to append */ |
23e9dde0 | 4183 | if (mas_wr_append(wr_mas, new_end)) |
54a611b6 | 4184 | return; |
54a611b6 | 4185 | |
0de56e38 | 4186 | if (new_end == mas->end && mas_wr_slot_store(wr_mas)) |
54a611b6 | 4187 | return; |
7a03ae39 PZ |
4188 | |
4189 | if (mas_wr_node_store(wr_mas, new_end)) | |
54a611b6 LH |
4190 | return; |
4191 | ||
4192 | if (mas_is_err(mas)) | |
4193 | return; | |
4194 | ||
4195 | slow_path: | |
4196 | mas_wr_bnode(wr_mas); | |
4197 | } | |
4198 | ||
4199 | /* | |
4200 | * mas_wr_store_entry() - Internal call to store a value | |
4201 | * @mas: The maple state | |
4202 | * @entry: The entry to store. | |
4203 | * | |
4204 | * Return: The contents that was stored at the index. | |
4205 | */ | |
4206 | static inline void *mas_wr_store_entry(struct ma_wr_state *wr_mas) | |
4207 | { | |
4208 | struct ma_state *mas = wr_mas->mas; | |
4209 | ||
4210 | wr_mas->content = mas_start(mas); | |
4211 | if (mas_is_none(mas) || mas_is_ptr(mas)) { | |
4212 | mas_store_root(mas, wr_mas->entry); | |
4213 | return wr_mas->content; | |
4214 | } | |
4215 | ||
4216 | if (unlikely(!mas_wr_walk(wr_mas))) { | |
4217 | mas_wr_spanning_store(wr_mas); | |
4218 | return wr_mas->content; | |
4219 | } | |
4220 | ||
4221 | /* At this point, we are at the leaf node that needs to be altered. */ | |
54a611b6 | 4222 | mas_wr_end_piv(wr_mas); |
54a611b6 LH |
4223 | /* New root for a single pointer */ |
4224 | if (unlikely(!mas->index && mas->last == ULONG_MAX)) { | |
4225 | mas_new_root(mas, wr_mas->entry); | |
4226 | return wr_mas->content; | |
4227 | } | |
4228 | ||
4229 | mas_wr_modify(wr_mas); | |
4230 | return wr_mas->content; | |
4231 | } | |
4232 | ||
4233 | /** | |
4234 | * mas_insert() - Internal call to insert a value | |
4235 | * @mas: The maple state | |
4236 | * @entry: The entry to store | |
4237 | * | |
4238 | * Return: %NULL or the contents that already exists at the requested index | |
4239 | * otherwise. The maple state needs to be checked for error conditions. | |
4240 | */ | |
4241 | static inline void *mas_insert(struct ma_state *mas, void *entry) | |
4242 | { | |
4243 | MA_WR_STATE(wr_mas, mas, entry); | |
4244 | ||
4245 | /* | |
4246 | * Inserting a new range inserts either 0, 1, or 2 pivots within the | |
4247 | * tree. If the insert fits exactly into an existing gap with a value | |
4248 | * of NULL, then the slot only needs to be written with the new value. | |
4249 | * If the range being inserted is adjacent to another range, then only a | |
4250 | * single pivot needs to be inserted (as well as writing the entry). If | |
4251 | * the new range is within a gap but does not touch any other ranges, | |
4252 | * then two pivots need to be inserted: the start - 1, and the end. As | |
4253 | * usual, the entry must be written. Most operations require a new node | |
4254 | * to be allocated and replace an existing node to ensure RCU safety, | |
4255 | * when in RCU mode. The exception to requiring a newly allocated node | |
4256 | * is when inserting at the end of a node (appending). When done | |
4257 | * carefully, appending can reuse the node in place. | |
4258 | */ | |
4259 | wr_mas.content = mas_start(mas); | |
4260 | if (wr_mas.content) | |
4261 | goto exists; | |
4262 | ||
4263 | if (mas_is_none(mas) || mas_is_ptr(mas)) { | |
4264 | mas_store_root(mas, entry); | |
4265 | return NULL; | |
4266 | } | |
4267 | ||
4268 | /* spanning writes always overwrite something */ | |
4269 | if (!mas_wr_walk(&wr_mas)) | |
4270 | goto exists; | |
4271 | ||
4272 | /* At this point, we are at the leaf node that needs to be altered. */ | |
4273 | wr_mas.offset_end = mas->offset; | |
4274 | wr_mas.end_piv = wr_mas.r_max; | |
4275 | ||
4276 | if (wr_mas.content || (mas->last > wr_mas.r_max)) | |
4277 | goto exists; | |
4278 | ||
4279 | if (!entry) | |
4280 | return NULL; | |
4281 | ||
4282 | mas_wr_modify(&wr_mas); | |
4283 | return wr_mas.content; | |
4284 | ||
4285 | exists: | |
4286 | mas_set_err(mas, -EEXIST); | |
4287 | return wr_mas.content; | |
4288 | ||
4289 | } | |
4290 | ||
9b6713cc CL |
4291 | /** |
4292 | * mas_alloc_cyclic() - Internal call to find somewhere to store an entry | |
4293 | * @mas: The maple state. | |
4294 | * @startp: Pointer to ID. | |
4295 | * @range_lo: Lower bound of range to search. | |
4296 | * @range_hi: Upper bound of range to search. | |
4297 | * @entry: The entry to store. | |
4298 | * @next: Pointer to next ID to allocate. | |
4299 | * @gfp: The GFP_FLAGS to use for allocations. | |
4300 | * | |
4301 | * Return: 0 if the allocation succeeded without wrapping, 1 if the | |
4302 | * allocation succeeded after wrapping, or -EBUSY if there are no | |
4303 | * free entries. | |
4304 | */ | |
4305 | int mas_alloc_cyclic(struct ma_state *mas, unsigned long *startp, | |
4306 | void *entry, unsigned long range_lo, unsigned long range_hi, | |
4307 | unsigned long *next, gfp_t gfp) | |
4308 | { | |
4309 | unsigned long min = range_lo; | |
4310 | int ret = 0; | |
4311 | ||
4312 | range_lo = max(min, *next); | |
4313 | ret = mas_empty_area(mas, range_lo, range_hi, 1); | |
4314 | if ((mas->tree->ma_flags & MT_FLAGS_ALLOC_WRAPPED) && ret == 0) { | |
4315 | mas->tree->ma_flags &= ~MT_FLAGS_ALLOC_WRAPPED; | |
4316 | ret = 1; | |
4317 | } | |
4318 | if (ret < 0 && range_lo > min) { | |
4319 | ret = mas_empty_area(mas, min, range_hi, 1); | |
4320 | if (ret == 0) | |
4321 | ret = 1; | |
4322 | } | |
4323 | if (ret < 0) | |
4324 | return ret; | |
4325 | ||
4326 | do { | |
4327 | mas_insert(mas, entry); | |
4328 | } while (mas_nomem(mas, gfp)); | |
4329 | if (mas_is_err(mas)) | |
4330 | return xa_err(mas->node); | |
4331 | ||
4332 | *startp = mas->index; | |
4333 | *next = *startp + 1; | |
4334 | if (*next == 0) | |
4335 | mas->tree->ma_flags |= MT_FLAGS_ALLOC_WRAPPED; | |
4336 | ||
4337 | return ret; | |
4338 | } | |
4339 | EXPORT_SYMBOL(mas_alloc_cyclic); | |
4340 | ||
271f61a8 | 4341 | static __always_inline void mas_rewalk(struct ma_state *mas, unsigned long index) |
de6e386c LH |
4342 | { |
4343 | retry: | |
4344 | mas_set(mas, index); | |
4345 | mas_state_walk(mas); | |
4346 | if (mas_is_start(mas)) | |
4347 | goto retry; | |
4348 | } | |
4349 | ||
271f61a8 | 4350 | static __always_inline bool mas_rewalk_if_dead(struct ma_state *mas, |
de6e386c LH |
4351 | struct maple_node *node, const unsigned long index) |
4352 | { | |
4353 | if (unlikely(ma_dead_node(node))) { | |
4354 | mas_rewalk(mas, index); | |
4355 | return true; | |
4356 | } | |
4357 | return false; | |
4358 | } | |
4359 | ||
54a611b6 LH |
4360 | /* |
4361 | * mas_prev_node() - Find the prev non-null entry at the same level in the | |
067311d3 LH |
4362 | * tree. The prev value will be mas->node[mas->offset] or the status will be |
4363 | * ma_none. | |
54a611b6 LH |
4364 | * @mas: The maple state |
4365 | * @min: The lower limit to search | |
4366 | * | |
067311d3 LH |
4367 | * The prev node value will be mas->node[mas->offset] or the status will be |
4368 | * ma_none. | |
54a611b6 LH |
4369 | * Return: 1 if the node is dead, 0 otherwise. |
4370 | */ | |
271f61a8 | 4371 | static int mas_prev_node(struct ma_state *mas, unsigned long min) |
54a611b6 LH |
4372 | { |
4373 | enum maple_type mt; | |
4374 | int offset, level; | |
4375 | void __rcu **slots; | |
4376 | struct maple_node *node; | |
54a611b6 | 4377 | unsigned long *pivots; |
dd9a8513 | 4378 | unsigned long max; |
54a611b6 | 4379 | |
dd9a8513 LH |
4380 | node = mas_mn(mas); |
4381 | if (!mas->min) | |
4382 | goto no_entry; | |
4383 | ||
4384 | max = mas->min - 1; | |
4385 | if (max < min) | |
4386 | goto no_entry; | |
54a611b6 LH |
4387 | |
4388 | level = 0; | |
4389 | do { | |
54a611b6 LH |
4390 | if (ma_is_root(node)) |
4391 | goto no_entry; | |
4392 | ||
4393 | /* Walk up. */ | |
4394 | if (unlikely(mas_ascend(mas))) | |
4395 | return 1; | |
4396 | offset = mas->offset; | |
4397 | level++; | |
dd9a8513 | 4398 | node = mas_mn(mas); |
54a611b6 LH |
4399 | } while (!offset); |
4400 | ||
4401 | offset--; | |
4402 | mt = mte_node_type(mas->node); | |
54a611b6 LH |
4403 | while (level > 1) { |
4404 | level--; | |
dd9a8513 LH |
4405 | slots = ma_slots(node, mt); |
4406 | mas->node = mas_slot(mas, slots, offset); | |
54a611b6 LH |
4407 | if (unlikely(ma_dead_node(node))) |
4408 | return 1; | |
4409 | ||
54a611b6 LH |
4410 | mt = mte_node_type(mas->node); |
4411 | node = mas_mn(mas); | |
54a611b6 | 4412 | pivots = ma_pivots(node, mt); |
dd9a8513 | 4413 | offset = ma_data_end(node, mt, pivots, max); |
39d0bd86 LH |
4414 | if (unlikely(ma_dead_node(node))) |
4415 | return 1; | |
54a611b6 LH |
4416 | } |
4417 | ||
dd9a8513 | 4418 | slots = ma_slots(node, mt); |
54a611b6 | 4419 | mas->node = mas_slot(mas, slots, offset); |
dd9a8513 | 4420 | pivots = ma_pivots(node, mt); |
54a611b6 LH |
4421 | if (unlikely(ma_dead_node(node))) |
4422 | return 1; | |
4423 | ||
dd9a8513 LH |
4424 | if (likely(offset)) |
4425 | mas->min = pivots[offset - 1] + 1; | |
4426 | mas->max = max; | |
54a611b6 LH |
4427 | mas->offset = mas_data_end(mas); |
4428 | if (unlikely(mte_dead_node(mas->node))) | |
4429 | return 1; | |
4430 | ||
31c532a8 | 4431 | mas->end = mas->offset; |
54a611b6 LH |
4432 | return 0; |
4433 | ||
54a611b6 LH |
4434 | no_entry: |
4435 | if (unlikely(ma_dead_node(node))) | |
4436 | return 1; | |
4437 | ||
067311d3 | 4438 | mas->status = ma_underflow; |
54a611b6 LH |
4439 | return 0; |
4440 | } | |
4441 | ||
dd9a8513 LH |
4442 | /* |
4443 | * mas_prev_slot() - Get the entry in the previous slot | |
4444 | * | |
4445 | * @mas: The maple state | |
4446 | * @max: The minimum starting range | |
a8091f03 LH |
4447 | * @empty: Can be empty |
4448 | * @set_underflow: Set the @mas->node to underflow state on limit. | |
dd9a8513 LH |
4449 | * |
4450 | * Return: The entry in the previous slot which is possibly NULL | |
4451 | */ | |
067311d3 | 4452 | static void *mas_prev_slot(struct ma_state *mas, unsigned long min, bool empty) |
dd9a8513 LH |
4453 | { |
4454 | void *entry; | |
4455 | void __rcu **slots; | |
4456 | unsigned long pivot; | |
4457 | enum maple_type type; | |
4458 | unsigned long *pivots; | |
4459 | struct maple_node *node; | |
4460 | unsigned long save_point = mas->index; | |
4461 | ||
4462 | retry: | |
4463 | node = mas_mn(mas); | |
4464 | type = mte_node_type(mas->node); | |
4465 | pivots = ma_pivots(node, type); | |
4466 | if (unlikely(mas_rewalk_if_dead(mas, node, save_point))) | |
4467 | goto retry; | |
4468 | ||
dd9a8513 LH |
4469 | if (mas->min <= min) { |
4470 | pivot = mas_safe_min(mas, pivots, mas->offset); | |
4471 | ||
4472 | if (unlikely(mas_rewalk_if_dead(mas, node, save_point))) | |
4473 | goto retry; | |
4474 | ||
4475 | if (pivot <= min) | |
a8091f03 | 4476 | goto underflow; |
dd9a8513 LH |
4477 | } |
4478 | ||
a8091f03 | 4479 | again: |
dd9a8513 LH |
4480 | if (likely(mas->offset)) { |
4481 | mas->offset--; | |
4482 | mas->last = mas->index - 1; | |
4483 | mas->index = mas_safe_min(mas, pivots, mas->offset); | |
4484 | } else { | |
067311d3 LH |
4485 | if (mas->index <= min) |
4486 | goto underflow; | |
4487 | ||
dd9a8513 LH |
4488 | if (mas_prev_node(mas, min)) { |
4489 | mas_rewalk(mas, save_point); | |
4490 | goto retry; | |
4491 | } | |
4492 | ||
067311d3 LH |
4493 | if (WARN_ON_ONCE(mas_is_underflow(mas))) |
4494 | return NULL; | |
dd9a8513 LH |
4495 | |
4496 | mas->last = mas->max; | |
4497 | node = mas_mn(mas); | |
4498 | type = mte_node_type(mas->node); | |
4499 | pivots = ma_pivots(node, type); | |
4500 | mas->index = pivots[mas->offset - 1] + 1; | |
4501 | } | |
4502 | ||
4503 | slots = ma_slots(node, type); | |
4504 | entry = mas_slot(mas, slots, mas->offset); | |
4505 | if (unlikely(mas_rewalk_if_dead(mas, node, save_point))) | |
4506 | goto retry; | |
4507 | ||
067311d3 | 4508 | |
dd9a8513 LH |
4509 | if (likely(entry)) |
4510 | return entry; | |
4511 | ||
a8091f03 | 4512 | if (!empty) { |
067311d3 LH |
4513 | if (mas->index <= min) { |
4514 | mas->status = ma_underflow; | |
4515 | return NULL; | |
4516 | } | |
a8091f03 | 4517 | |
dd9a8513 | 4518 | goto again; |
a8091f03 | 4519 | } |
dd9a8513 LH |
4520 | |
4521 | return entry; | |
a8091f03 LH |
4522 | |
4523 | underflow: | |
067311d3 | 4524 | mas->status = ma_underflow; |
a8091f03 | 4525 | return NULL; |
dd9a8513 LH |
4526 | } |
4527 | ||
54a611b6 LH |
4528 | /* |
4529 | * mas_next_node() - Get the next node at the same level in the tree. | |
4530 | * @mas: The maple state | |
4531 | * @max: The maximum pivot value to check. | |
4532 | * | |
067311d3 LH |
4533 | * The next value will be mas->node[mas->offset] or the status will have |
4534 | * overflowed. | |
54a611b6 LH |
4535 | * Return: 1 on dead node, 0 otherwise. |
4536 | */ | |
271f61a8 LH |
4537 | static int mas_next_node(struct ma_state *mas, struct maple_node *node, |
4538 | unsigned long max) | |
54a611b6 | 4539 | { |
fff4a58c | 4540 | unsigned long min; |
54a611b6 LH |
4541 | unsigned long *pivots; |
4542 | struct maple_enode *enode; | |
e9c52d89 | 4543 | struct maple_node *tmp; |
54a611b6 | 4544 | int level = 0; |
39d0bd86 | 4545 | unsigned char node_end; |
54a611b6 LH |
4546 | enum maple_type mt; |
4547 | void __rcu **slots; | |
4548 | ||
4549 | if (mas->max >= max) | |
067311d3 | 4550 | goto overflow; |
54a611b6 | 4551 | |
fff4a58c | 4552 | min = mas->max + 1; |
54a611b6 LH |
4553 | level = 0; |
4554 | do { | |
4555 | if (ma_is_root(node)) | |
067311d3 | 4556 | goto overflow; |
54a611b6 | 4557 | |
fff4a58c | 4558 | /* Walk up. */ |
54a611b6 LH |
4559 | if (unlikely(mas_ascend(mas))) |
4560 | return 1; | |
4561 | ||
54a611b6 LH |
4562 | level++; |
4563 | node = mas_mn(mas); | |
4564 | mt = mte_node_type(mas->node); | |
4565 | pivots = ma_pivots(node, mt); | |
39d0bd86 LH |
4566 | node_end = ma_data_end(node, mt, pivots, mas->max); |
4567 | if (unlikely(ma_dead_node(node))) | |
4568 | return 1; | |
4569 | ||
fff4a58c | 4570 | } while (unlikely(mas->offset == node_end)); |
54a611b6 LH |
4571 | |
4572 | slots = ma_slots(node, mt); | |
fff4a58c LH |
4573 | mas->offset++; |
4574 | enode = mas_slot(mas, slots, mas->offset); | |
4575 | if (unlikely(ma_dead_node(node))) | |
4576 | return 1; | |
54a611b6 | 4577 | |
fff4a58c LH |
4578 | if (level > 1) |
4579 | mas->offset = 0; | |
4580 | ||
4581 | while (unlikely(level > 1)) { | |
54a611b6 | 4582 | level--; |
fff4a58c | 4583 | mas->node = enode; |
54a611b6 LH |
4584 | node = mas_mn(mas); |
4585 | mt = mte_node_type(mas->node); | |
4586 | slots = ma_slots(node, mt); | |
fff4a58c | 4587 | enode = mas_slot(mas, slots, 0); |
39d0bd86 LH |
4588 | if (unlikely(ma_dead_node(node))) |
4589 | return 1; | |
54a611b6 LH |
4590 | } |
4591 | ||
fff4a58c LH |
4592 | if (!mas->offset) |
4593 | pivots = ma_pivots(node, mt); | |
4594 | ||
4595 | mas->max = mas_safe_pivot(mas, pivots, mas->offset, mt); | |
e9c52d89 LH |
4596 | tmp = mte_to_node(enode); |
4597 | mt = mte_node_type(enode); | |
4598 | pivots = ma_pivots(tmp, mt); | |
4599 | mas->end = ma_data_end(tmp, mt, pivots, mas->max); | |
54a611b6 LH |
4600 | if (unlikely(ma_dead_node(node))) |
4601 | return 1; | |
4602 | ||
4603 | mas->node = enode; | |
4604 | mas->min = min; | |
54a611b6 LH |
4605 | return 0; |
4606 | ||
067311d3 | 4607 | overflow: |
54a611b6 LH |
4608 | if (unlikely(ma_dead_node(node))) |
4609 | return 1; | |
4610 | ||
067311d3 | 4611 | mas->status = ma_overflow; |
54a611b6 LH |
4612 | return 0; |
4613 | } | |
4614 | ||
4615 | /* | |
fff4a58c | 4616 | * mas_next_slot() - Get the entry in the next slot |
54a611b6 | 4617 | * |
fff4a58c LH |
4618 | * @mas: The maple state |
4619 | * @max: The maximum starting range | |
4620 | * @empty: Can be empty | |
a8091f03 LH |
4621 | * @set_overflow: Should @mas->node be set to overflow when the limit is |
4622 | * reached. | |
54a611b6 | 4623 | * |
fff4a58c | 4624 | * Return: The entry in the next slot which is possibly NULL |
54a611b6 | 4625 | */ |
067311d3 | 4626 | static void *mas_next_slot(struct ma_state *mas, unsigned long max, bool empty) |
54a611b6 | 4627 | { |
54a611b6 | 4628 | void __rcu **slots; |
fff4a58c LH |
4629 | unsigned long *pivots; |
4630 | unsigned long pivot; | |
4631 | enum maple_type type; | |
4632 | struct maple_node *node; | |
fff4a58c | 4633 | unsigned long save_point = mas->last; |
54a611b6 LH |
4634 | void *entry; |
4635 | ||
fff4a58c LH |
4636 | retry: |
4637 | node = mas_mn(mas); | |
4638 | type = mte_node_type(mas->node); | |
39d0bd86 | 4639 | pivots = ma_pivots(node, type); |
fff4a58c LH |
4640 | if (unlikely(mas_rewalk_if_dead(mas, node, save_point))) |
4641 | goto retry; | |
54a611b6 | 4642 | |
fff4a58c | 4643 | if (mas->max >= max) { |
e9c52d89 | 4644 | if (likely(mas->offset < mas->end)) |
fff4a58c LH |
4645 | pivot = pivots[mas->offset]; |
4646 | else | |
067311d3 | 4647 | pivot = mas->max; |
54a611b6 | 4648 | |
fff4a58c LH |
4649 | if (unlikely(mas_rewalk_if_dead(mas, node, save_point))) |
4650 | goto retry; | |
54a611b6 | 4651 | |
067311d3 LH |
4652 | if (pivot >= max) { /* Was at the limit, next will extend beyond */ |
4653 | mas->status = ma_overflow; | |
4654 | return NULL; | |
4655 | } | |
fff4a58c | 4656 | } |
54a611b6 | 4657 | |
e9c52d89 | 4658 | if (likely(mas->offset < mas->end)) { |
fff4a58c | 4659 | mas->index = pivots[mas->offset] + 1; |
a8091f03 | 4660 | again: |
fff4a58c | 4661 | mas->offset++; |
e9c52d89 | 4662 | if (likely(mas->offset < mas->end)) |
fff4a58c LH |
4663 | mas->last = pivots[mas->offset]; |
4664 | else | |
4665 | mas->last = mas->max; | |
4666 | } else { | |
067311d3 LH |
4667 | if (mas->last >= max) { |
4668 | mas->status = ma_overflow; | |
4669 | return NULL; | |
4670 | } | |
4671 | ||
fff4a58c LH |
4672 | if (mas_next_node(mas, node, max)) { |
4673 | mas_rewalk(mas, save_point); | |
4674 | goto retry; | |
4675 | } | |
4676 | ||
067311d3 | 4677 | if (WARN_ON_ONCE(mas_is_overflow(mas))) |
ca80f610 LH |
4678 | return NULL; |
4679 | ||
fff4a58c LH |
4680 | mas->offset = 0; |
4681 | mas->index = mas->min; | |
4682 | node = mas_mn(mas); | |
4683 | type = mte_node_type(mas->node); | |
4684 | pivots = ma_pivots(node, type); | |
4685 | mas->last = pivots[0]; | |
54a611b6 LH |
4686 | } |
4687 | ||
fff4a58c LH |
4688 | slots = ma_slots(node, type); |
4689 | entry = mt_slot(mas->tree, slots, mas->offset); | |
4690 | if (unlikely(mas_rewalk_if_dead(mas, node, save_point))) | |
4691 | goto retry; | |
54a611b6 | 4692 | |
fff4a58c LH |
4693 | if (entry) |
4694 | return entry; | |
54a611b6 | 4695 | |
067311d3 | 4696 | |
fff4a58c | 4697 | if (!empty) { |
067311d3 LH |
4698 | if (mas->last >= max) { |
4699 | mas->status = ma_overflow; | |
4700 | return NULL; | |
4701 | } | |
a8091f03 LH |
4702 | |
4703 | mas->index = mas->last + 1; | |
fff4a58c LH |
4704 | goto again; |
4705 | } | |
4706 | ||
4707 | return entry; | |
54a611b6 LH |
4708 | } |
4709 | ||
4710 | /* | |
4711 | * mas_next_entry() - Internal function to get the next entry. | |
4712 | * @mas: The maple state | |
4713 | * @limit: The maximum range start. | |
4714 | * | |
4715 | * Set the @mas->node to the next entry and the range_start to | |
4716 | * the beginning value for the entry. Does not check beyond @limit. | |
a8091f03 LH |
4717 | * Sets @mas->index and @mas->last to the range, Does not update @mas->index and |
4718 | * @mas->last on overflow. | |
54a611b6 LH |
4719 | * Restarts on dead nodes. |
4720 | * | |
4721 | * Return: the next entry or %NULL. | |
4722 | */ | |
4723 | static inline void *mas_next_entry(struct ma_state *mas, unsigned long limit) | |
4724 | { | |
a8091f03 | 4725 | if (mas->last >= limit) { |
067311d3 | 4726 | mas->status = ma_overflow; |
50e81c82 | 4727 | return NULL; |
a8091f03 | 4728 | } |
ca80f610 | 4729 | |
067311d3 | 4730 | return mas_next_slot(mas, limit, false); |
54a611b6 LH |
4731 | } |
4732 | ||
54a611b6 LH |
4733 | /* |
4734 | * mas_rev_awalk() - Internal function. Reverse allocation walk. Find the | |
4735 | * highest gap address of a given size in a given node and descend. | |
4736 | * @mas: The maple state | |
4737 | * @size: The needed size. | |
4738 | * | |
4739 | * Return: True if found in a leaf, false otherwise. | |
4740 | * | |
4741 | */ | |
fad8e429 LH |
4742 | static bool mas_rev_awalk(struct ma_state *mas, unsigned long size, |
4743 | unsigned long *gap_min, unsigned long *gap_max) | |
54a611b6 LH |
4744 | { |
4745 | enum maple_type type = mte_node_type(mas->node); | |
4746 | struct maple_node *node = mas_mn(mas); | |
4747 | unsigned long *pivots, *gaps; | |
4748 | void __rcu **slots; | |
4749 | unsigned long gap = 0; | |
7327e811 | 4750 | unsigned long max, min; |
54a611b6 LH |
4751 | unsigned char offset; |
4752 | ||
4753 | if (unlikely(mas_is_err(mas))) | |
4754 | return true; | |
4755 | ||
4756 | if (ma_is_dense(type)) { | |
4757 | /* dense nodes. */ | |
4758 | mas->offset = (unsigned char)(mas->index - mas->min); | |
4759 | return true; | |
4760 | } | |
4761 | ||
4762 | pivots = ma_pivots(node, type); | |
4763 | slots = ma_slots(node, type); | |
4764 | gaps = ma_gaps(node, type); | |
4765 | offset = mas->offset; | |
4766 | min = mas_safe_min(mas, pivots, offset); | |
4767 | /* Skip out of bounds. */ | |
4768 | while (mas->last < min) | |
4769 | min = mas_safe_min(mas, pivots, --offset); | |
4770 | ||
4771 | max = mas_safe_pivot(mas, pivots, offset, type); | |
7327e811 | 4772 | while (mas->index <= max) { |
54a611b6 LH |
4773 | gap = 0; |
4774 | if (gaps) | |
4775 | gap = gaps[offset]; | |
4776 | else if (!mas_slot(mas, slots, offset)) | |
4777 | gap = max - min + 1; | |
4778 | ||
4779 | if (gap) { | |
4780 | if ((size <= gap) && (size <= mas->last - min + 1)) | |
4781 | break; | |
4782 | ||
4783 | if (!gaps) { | |
4784 | /* Skip the next slot, it cannot be a gap. */ | |
4785 | if (offset < 2) | |
4786 | goto ascend; | |
4787 | ||
4788 | offset -= 2; | |
4789 | max = pivots[offset]; | |
4790 | min = mas_safe_min(mas, pivots, offset); | |
4791 | continue; | |
4792 | } | |
4793 | } | |
4794 | ||
4795 | if (!offset) | |
4796 | goto ascend; | |
4797 | ||
4798 | offset--; | |
4799 | max = min - 1; | |
4800 | min = mas_safe_min(mas, pivots, offset); | |
4801 | } | |
4802 | ||
7327e811 LH |
4803 | if (unlikely((mas->index > max) || (size - 1 > max - mas->index))) |
4804 | goto no_space; | |
54a611b6 LH |
4805 | |
4806 | if (unlikely(ma_is_leaf(type))) { | |
4807 | mas->offset = offset; | |
fad8e429 LH |
4808 | *gap_min = min; |
4809 | *gap_max = min + gap - 1; | |
54a611b6 LH |
4810 | return true; |
4811 | } | |
4812 | ||
4813 | /* descend, only happens under lock. */ | |
4814 | mas->node = mas_slot(mas, slots, offset); | |
4815 | mas->min = min; | |
4816 | mas->max = max; | |
4817 | mas->offset = mas_data_end(mas); | |
4818 | return false; | |
4819 | ||
4820 | ascend: | |
7327e811 LH |
4821 | if (!mte_is_root(mas->node)) |
4822 | return false; | |
54a611b6 | 4823 | |
7327e811 LH |
4824 | no_space: |
4825 | mas_set_err(mas, -EBUSY); | |
54a611b6 LH |
4826 | return false; |
4827 | } | |
4828 | ||
4829 | static inline bool mas_anode_descend(struct ma_state *mas, unsigned long size) | |
4830 | { | |
4831 | enum maple_type type = mte_node_type(mas->node); | |
4832 | unsigned long pivot, min, gap = 0; | |
06e8fd99 LH |
4833 | unsigned char offset, data_end; |
4834 | unsigned long *gaps, *pivots; | |
4835 | void __rcu **slots; | |
4836 | struct maple_node *node; | |
54a611b6 LH |
4837 | bool found = false; |
4838 | ||
4839 | if (ma_is_dense(type)) { | |
4840 | mas->offset = (unsigned char)(mas->index - mas->min); | |
4841 | return true; | |
4842 | } | |
4843 | ||
06e8fd99 LH |
4844 | node = mas_mn(mas); |
4845 | pivots = ma_pivots(node, type); | |
4846 | slots = ma_slots(node, type); | |
4847 | gaps = ma_gaps(node, type); | |
54a611b6 | 4848 | offset = mas->offset; |
54a611b6 | 4849 | min = mas_safe_min(mas, pivots, offset); |
06e8fd99 LH |
4850 | data_end = ma_data_end(node, type, pivots, mas->max); |
4851 | for (; offset <= data_end; offset++) { | |
29b2681f | 4852 | pivot = mas_safe_pivot(mas, pivots, offset, type); |
54a611b6 LH |
4853 | |
4854 | /* Not within lower bounds */ | |
4855 | if (mas->index > pivot) | |
4856 | goto next_slot; | |
4857 | ||
4858 | if (gaps) | |
4859 | gap = gaps[offset]; | |
4860 | else if (!mas_slot(mas, slots, offset)) | |
4861 | gap = min(pivot, mas->last) - max(mas->index, min) + 1; | |
4862 | else | |
4863 | goto next_slot; | |
4864 | ||
4865 | if (gap >= size) { | |
4866 | if (ma_is_leaf(type)) { | |
4867 | found = true; | |
4868 | goto done; | |
4869 | } | |
4870 | if (mas->index <= pivot) { | |
4871 | mas->node = mas_slot(mas, slots, offset); | |
4872 | mas->min = min; | |
4873 | mas->max = pivot; | |
4874 | offset = 0; | |
54a611b6 LH |
4875 | break; |
4876 | } | |
4877 | } | |
4878 | next_slot: | |
4879 | min = pivot + 1; | |
4880 | if (mas->last <= pivot) { | |
4881 | mas_set_err(mas, -EBUSY); | |
4882 | return true; | |
4883 | } | |
4884 | } | |
4885 | ||
4886 | if (mte_is_root(mas->node)) | |
4887 | found = true; | |
4888 | done: | |
4889 | mas->offset = offset; | |
4890 | return found; | |
4891 | } | |
4892 | ||
4893 | /** | |
4894 | * mas_walk() - Search for @mas->index in the tree. | |
4895 | * @mas: The maple state. | |
4896 | * | |
4897 | * mas->index and mas->last will be set to the range if there is a value. If | |
067311d3 | 4898 | * mas->status is ma_none, reset to ma_start |
54a611b6 LH |
4899 | * |
4900 | * Return: the entry at the location or %NULL. | |
4901 | */ | |
4902 | void *mas_walk(struct ma_state *mas) | |
4903 | { | |
4904 | void *entry; | |
4905 | ||
a8091f03 | 4906 | if (!mas_is_active(mas) || !mas_is_start(mas)) |
067311d3 | 4907 | mas->status = ma_start; |
54a611b6 LH |
4908 | retry: |
4909 | entry = mas_state_walk(mas); | |
6b23a290 | 4910 | if (mas_is_start(mas)) { |
54a611b6 | 4911 | goto retry; |
6b23a290 LH |
4912 | } else if (mas_is_none(mas)) { |
4913 | mas->index = 0; | |
4914 | mas->last = ULONG_MAX; | |
4915 | } else if (mas_is_ptr(mas)) { | |
54a611b6 LH |
4916 | if (!mas->index) { |
4917 | mas->last = 0; | |
6b23a290 | 4918 | return entry; |
54a611b6 | 4919 | } |
54a611b6 | 4920 | |
6b23a290 | 4921 | mas->index = 1; |
54a611b6 | 4922 | mas->last = ULONG_MAX; |
067311d3 | 4923 | mas->status = ma_none; |
6b23a290 | 4924 | return NULL; |
54a611b6 LH |
4925 | } |
4926 | ||
4927 | return entry; | |
4928 | } | |
120b1162 | 4929 | EXPORT_SYMBOL_GPL(mas_walk); |
54a611b6 LH |
4930 | |
4931 | static inline bool mas_rewind_node(struct ma_state *mas) | |
4932 | { | |
4933 | unsigned char slot; | |
4934 | ||
4935 | do { | |
4936 | if (mte_is_root(mas->node)) { | |
4937 | slot = mas->offset; | |
4938 | if (!slot) | |
4939 | return false; | |
4940 | } else { | |
4941 | mas_ascend(mas); | |
4942 | slot = mas->offset; | |
4943 | } | |
4944 | } while (!slot); | |
4945 | ||
4946 | mas->offset = --slot; | |
4947 | return true; | |
4948 | } | |
4949 | ||
4950 | /* | |
4951 | * mas_skip_node() - Internal function. Skip over a node. | |
4952 | * @mas: The maple state. | |
4953 | * | |
4954 | * Return: true if there is another node, false otherwise. | |
4955 | */ | |
4956 | static inline bool mas_skip_node(struct ma_state *mas) | |
4957 | { | |
0fa99fdf LH |
4958 | if (mas_is_err(mas)) |
4959 | return false; | |
54a611b6 | 4960 | |
54a611b6 LH |
4961 | do { |
4962 | if (mte_is_root(mas->node)) { | |
0fa99fdf | 4963 | if (mas->offset >= mas_data_end(mas)) { |
54a611b6 LH |
4964 | mas_set_err(mas, -EBUSY); |
4965 | return false; | |
4966 | } | |
4967 | } else { | |
4968 | mas_ascend(mas); | |
54a611b6 | 4969 | } |
0fa99fdf | 4970 | } while (mas->offset >= mas_data_end(mas)); |
54a611b6 | 4971 | |
0fa99fdf | 4972 | mas->offset++; |
54a611b6 LH |
4973 | return true; |
4974 | } | |
4975 | ||
4976 | /* | |
4977 | * mas_awalk() - Allocation walk. Search from low address to high, for a gap of | |
4978 | * @size | |
4979 | * @mas: The maple state | |
4980 | * @size: The size of the gap required | |
4981 | * | |
4982 | * Search between @mas->index and @mas->last for a gap of @size. | |
4983 | */ | |
4984 | static inline void mas_awalk(struct ma_state *mas, unsigned long size) | |
4985 | { | |
4986 | struct maple_enode *last = NULL; | |
4987 | ||
4988 | /* | |
4989 | * There are 4 options: | |
4990 | * go to child (descend) | |
4991 | * go back to parent (ascend) | |
4992 | * no gap found. (return, slot == MAPLE_NODE_SLOTS) | |
4993 | * found the gap. (return, slot != MAPLE_NODE_SLOTS) | |
4994 | */ | |
4995 | while (!mas_is_err(mas) && !mas_anode_descend(mas, size)) { | |
4996 | if (last == mas->node) | |
4997 | mas_skip_node(mas); | |
4998 | else | |
4999 | last = mas->node; | |
5000 | } | |
5001 | } | |
5002 | ||
54a611b6 LH |
5003 | /* |
5004 | * mas_sparse_area() - Internal function. Return upper or lower limit when | |
5005 | * searching for a gap in an empty tree. | |
5006 | * @mas: The maple state | |
5007 | * @min: the minimum range | |
5008 | * @max: The maximum range | |
5009 | * @size: The size of the gap | |
5010 | * @fwd: Searching forward or back | |
5011 | */ | |
29ad6bb3 | 5012 | static inline int mas_sparse_area(struct ma_state *mas, unsigned long min, |
54a611b6 LH |
5013 | unsigned long max, unsigned long size, bool fwd) |
5014 | { | |
29ad6bb3 PZ |
5015 | if (!unlikely(mas_is_none(mas)) && min == 0) { |
5016 | min++; | |
5017 | /* | |
5018 | * At this time, min is increased, we need to recheck whether | |
5019 | * the size is satisfied. | |
5020 | */ | |
5021 | if (min > max || max - min + 1 < size) | |
5022 | return -EBUSY; | |
5023 | } | |
54a611b6 LH |
5024 | /* mas_is_ptr */ |
5025 | ||
54a611b6 | 5026 | if (fwd) { |
29ad6bb3 PZ |
5027 | mas->index = min; |
5028 | mas->last = min + size - 1; | |
5029 | } else { | |
5030 | mas->last = max; | |
5031 | mas->index = max - size + 1; | |
54a611b6 | 5032 | } |
29ad6bb3 | 5033 | return 0; |
54a611b6 LH |
5034 | } |
5035 | ||
5036 | /* | |
5037 | * mas_empty_area() - Get the lowest address within the range that is | |
5038 | * sufficient for the size requested. | |
5039 | * @mas: The maple state | |
5040 | * @min: The lowest value of the range | |
5041 | * @max: The highest value of the range | |
5042 | * @size: The size needed | |
5043 | */ | |
5044 | int mas_empty_area(struct ma_state *mas, unsigned long min, | |
5045 | unsigned long max, unsigned long size) | |
5046 | { | |
5047 | unsigned char offset; | |
5048 | unsigned long *pivots; | |
5049 | enum maple_type mt; | |
0de56e38 | 5050 | struct maple_node *node; |
54a611b6 | 5051 | |
ba997212 LH |
5052 | if (min > max) |
5053 | return -EINVAL; | |
5054 | ||
5055 | if (size == 0 || max - min < size - 1) | |
fad8e429 LH |
5056 | return -EINVAL; |
5057 | ||
54a611b6 LH |
5058 | if (mas_is_start(mas)) |
5059 | mas_start(mas); | |
5060 | else if (mas->offset >= 2) | |
5061 | mas->offset -= 2; | |
5062 | else if (!mas_skip_node(mas)) | |
5063 | return -EBUSY; | |
5064 | ||
5065 | /* Empty set */ | |
29ad6bb3 PZ |
5066 | if (mas_is_none(mas) || mas_is_ptr(mas)) |
5067 | return mas_sparse_area(mas, min, max, size, true); | |
54a611b6 LH |
5068 | |
5069 | /* The start of the window can only be within these values */ | |
5070 | mas->index = min; | |
5071 | mas->last = max; | |
5072 | mas_awalk(mas, size); | |
5073 | ||
5074 | if (unlikely(mas_is_err(mas))) | |
5075 | return xa_err(mas->node); | |
5076 | ||
5077 | offset = mas->offset; | |
5078 | if (unlikely(offset == MAPLE_NODE_SLOTS)) | |
5079 | return -EBUSY; | |
5080 | ||
0de56e38 | 5081 | node = mas_mn(mas); |
54a611b6 | 5082 | mt = mte_node_type(mas->node); |
0de56e38 | 5083 | pivots = ma_pivots(node, mt); |
0257d990 PZ |
5084 | min = mas_safe_min(mas, pivots, offset); |
5085 | if (mas->index < min) | |
5086 | mas->index = min; | |
54a611b6 | 5087 | mas->last = mas->index + size - 1; |
0de56e38 | 5088 | mas->end = ma_data_end(node, mt, pivots, mas->max); |
54a611b6 LH |
5089 | return 0; |
5090 | } | |
120b1162 | 5091 | EXPORT_SYMBOL_GPL(mas_empty_area); |
54a611b6 LH |
5092 | |
5093 | /* | |
5094 | * mas_empty_area_rev() - Get the highest address within the range that is | |
5095 | * sufficient for the size requested. | |
5096 | * @mas: The maple state | |
5097 | * @min: The lowest value of the range | |
5098 | * @max: The highest value of the range | |
5099 | * @size: The size needed | |
5100 | */ | |
5101 | int mas_empty_area_rev(struct ma_state *mas, unsigned long min, | |
5102 | unsigned long max, unsigned long size) | |
5103 | { | |
5104 | struct maple_enode *last = mas->node; | |
5105 | ||
ba997212 LH |
5106 | if (min > max) |
5107 | return -EINVAL; | |
5108 | ||
5109 | if (size == 0 || max - min < size - 1) | |
fad8e429 LH |
5110 | return -EINVAL; |
5111 | ||
54a611b6 LH |
5112 | if (mas_is_start(mas)) { |
5113 | mas_start(mas); | |
5114 | mas->offset = mas_data_end(mas); | |
5115 | } else if (mas->offset >= 2) { | |
5116 | mas->offset -= 2; | |
5117 | } else if (!mas_rewind_node(mas)) { | |
5118 | return -EBUSY; | |
5119 | } | |
5120 | ||
5121 | /* Empty set. */ | |
29ad6bb3 PZ |
5122 | if (mas_is_none(mas) || mas_is_ptr(mas)) |
5123 | return mas_sparse_area(mas, min, max, size, false); | |
54a611b6 LH |
5124 | |
5125 | /* The start of the window can only be within these values. */ | |
5126 | mas->index = min; | |
5127 | mas->last = max; | |
5128 | ||
fad8e429 | 5129 | while (!mas_rev_awalk(mas, size, &min, &max)) { |
54a611b6 LH |
5130 | if (last == mas->node) { |
5131 | if (!mas_rewind_node(mas)) | |
5132 | return -EBUSY; | |
5133 | } else { | |
5134 | last = mas->node; | |
5135 | } | |
5136 | } | |
5137 | ||
5138 | if (mas_is_err(mas)) | |
5139 | return xa_err(mas->node); | |
5140 | ||
5141 | if (unlikely(mas->offset == MAPLE_NODE_SLOTS)) | |
5142 | return -EBUSY; | |
5143 | ||
54a611b6 | 5144 | /* Trim the upper limit to the max. */ |
ba997212 | 5145 | if (max < mas->last) |
fad8e429 | 5146 | mas->last = max; |
54a611b6 LH |
5147 | |
5148 | mas->index = mas->last - size + 1; | |
31c532a8 | 5149 | mas->end = mas_data_end(mas); |
54a611b6 LH |
5150 | return 0; |
5151 | } | |
120b1162 | 5152 | EXPORT_SYMBOL_GPL(mas_empty_area_rev); |
54a611b6 | 5153 | |
54a611b6 | 5154 | /* |
790e1fa8 | 5155 | * mte_dead_leaves() - Mark all leaves of a node as dead. |
54a611b6 LH |
5156 | * @mas: The maple state |
5157 | * @slots: Pointer to the slot array | |
2e5b4921 | 5158 | * @type: The maple node type |
54a611b6 LH |
5159 | * |
5160 | * Must hold the write lock. | |
5161 | * | |
5162 | * Return: The number of leaves marked as dead. | |
5163 | */ | |
5164 | static inline | |
790e1fa8 LH |
5165 | unsigned char mte_dead_leaves(struct maple_enode *enode, struct maple_tree *mt, |
5166 | void __rcu **slots) | |
54a611b6 LH |
5167 | { |
5168 | struct maple_node *node; | |
5169 | enum maple_type type; | |
5170 | void *entry; | |
5171 | int offset; | |
5172 | ||
790e1fa8 LH |
5173 | for (offset = 0; offset < mt_slot_count(enode); offset++) { |
5174 | entry = mt_slot(mt, slots, offset); | |
54a611b6 LH |
5175 | type = mte_node_type(entry); |
5176 | node = mte_to_node(entry); | |
5177 | /* Use both node and type to catch LE & BE metadata */ | |
5178 | if (!node || !type) | |
5179 | break; | |
5180 | ||
5181 | mte_set_node_dead(entry); | |
54a611b6 LH |
5182 | node->type = type; |
5183 | rcu_assign_pointer(slots[offset], node); | |
5184 | } | |
5185 | ||
5186 | return offset; | |
5187 | } | |
5188 | ||
790e1fa8 LH |
5189 | /** |
5190 | * mte_dead_walk() - Walk down a dead tree to just before the leaves | |
5191 | * @enode: The maple encoded node | |
5192 | * @offset: The starting offset | |
5193 | * | |
5194 | * Note: This can only be used from the RCU callback context. | |
5195 | */ | |
5196 | static void __rcu **mte_dead_walk(struct maple_enode **enode, unsigned char offset) | |
54a611b6 LH |
5197 | { |
5198 | struct maple_node *node, *next; | |
5199 | void __rcu **slots = NULL; | |
5200 | ||
790e1fa8 | 5201 | next = mte_to_node(*enode); |
54a611b6 | 5202 | do { |
790e1fa8 LH |
5203 | *enode = ma_enode_ptr(next); |
5204 | node = mte_to_node(*enode); | |
54a611b6 | 5205 | slots = ma_slots(node, node->type); |
790e1fa8 LH |
5206 | next = rcu_dereference_protected(slots[offset], |
5207 | lock_is_held(&rcu_callback_map)); | |
54a611b6 LH |
5208 | offset = 0; |
5209 | } while (!ma_is_leaf(next->type)); | |
5210 | ||
5211 | return slots; | |
5212 | } | |
5213 | ||
790e1fa8 LH |
5214 | /** |
5215 | * mt_free_walk() - Walk & free a tree in the RCU callback context | |
5216 | * @head: The RCU head that's within the node. | |
5217 | * | |
5218 | * Note: This can only be used from the RCU callback context. | |
5219 | */ | |
54a611b6 LH |
5220 | static void mt_free_walk(struct rcu_head *head) |
5221 | { | |
5222 | void __rcu **slots; | |
5223 | struct maple_node *node, *start; | |
790e1fa8 | 5224 | struct maple_enode *enode; |
54a611b6 LH |
5225 | unsigned char offset; |
5226 | enum maple_type type; | |
54a611b6 LH |
5227 | |
5228 | node = container_of(head, struct maple_node, rcu); | |
5229 | ||
5230 | if (ma_is_leaf(node->type)) | |
5231 | goto free_leaf; | |
5232 | ||
54a611b6 | 5233 | start = node; |
790e1fa8 LH |
5234 | enode = mt_mk_node(node, node->type); |
5235 | slots = mte_dead_walk(&enode, 0); | |
5236 | node = mte_to_node(enode); | |
54a611b6 LH |
5237 | do { |
5238 | mt_free_bulk(node->slot_len, slots); | |
5239 | offset = node->parent_slot + 1; | |
790e1fa8 LH |
5240 | enode = node->piv_parent; |
5241 | if (mte_to_node(enode) == node) | |
5242 | goto free_leaf; | |
5243 | ||
5244 | type = mte_node_type(enode); | |
5245 | slots = ma_slots(mte_to_node(enode), type); | |
5246 | if ((offset < mt_slots[type]) && | |
5247 | rcu_dereference_protected(slots[offset], | |
5248 | lock_is_held(&rcu_callback_map))) | |
5249 | slots = mte_dead_walk(&enode, offset); | |
5250 | node = mte_to_node(enode); | |
54a611b6 LH |
5251 | } while ((node != start) || (node->slot_len < offset)); |
5252 | ||
5253 | slots = ma_slots(node, node->type); | |
5254 | mt_free_bulk(node->slot_len, slots); | |
5255 | ||
54a611b6 LH |
5256 | free_leaf: |
5257 | mt_free_rcu(&node->rcu); | |
5258 | } | |
5259 | ||
790e1fa8 LH |
5260 | static inline void __rcu **mte_destroy_descend(struct maple_enode **enode, |
5261 | struct maple_tree *mt, struct maple_enode *prev, unsigned char offset) | |
54a611b6 LH |
5262 | { |
5263 | struct maple_node *node; | |
790e1fa8 | 5264 | struct maple_enode *next = *enode; |
54a611b6 | 5265 | void __rcu **slots = NULL; |
790e1fa8 LH |
5266 | enum maple_type type; |
5267 | unsigned char next_offset = 0; | |
54a611b6 LH |
5268 | |
5269 | do { | |
790e1fa8 LH |
5270 | *enode = next; |
5271 | node = mte_to_node(*enode); | |
5272 | type = mte_node_type(*enode); | |
5273 | slots = ma_slots(node, type); | |
5274 | next = mt_slot_locked(mt, slots, next_offset); | |
54a611b6 | 5275 | if ((mte_dead_node(next))) |
790e1fa8 | 5276 | next = mt_slot_locked(mt, slots, ++next_offset); |
54a611b6 | 5277 | |
790e1fa8 LH |
5278 | mte_set_node_dead(*enode); |
5279 | node->type = type; | |
54a611b6 LH |
5280 | node->piv_parent = prev; |
5281 | node->parent_slot = offset; | |
790e1fa8 LH |
5282 | offset = next_offset; |
5283 | next_offset = 0; | |
5284 | prev = *enode; | |
54a611b6 LH |
5285 | } while (!mte_is_leaf(next)); |
5286 | ||
5287 | return slots; | |
5288 | } | |
5289 | ||
790e1fa8 | 5290 | static void mt_destroy_walk(struct maple_enode *enode, struct maple_tree *mt, |
54a611b6 LH |
5291 | bool free) |
5292 | { | |
5293 | void __rcu **slots; | |
5294 | struct maple_node *node = mte_to_node(enode); | |
5295 | struct maple_enode *start; | |
54a611b6 | 5296 | |
2e5b4921 LH |
5297 | if (mte_is_leaf(enode)) { |
5298 | node->type = mte_node_type(enode); | |
54a611b6 | 5299 | goto free_leaf; |
2e5b4921 | 5300 | } |
54a611b6 | 5301 | |
2e5b4921 | 5302 | start = enode; |
790e1fa8 LH |
5303 | slots = mte_destroy_descend(&enode, mt, start, 0); |
5304 | node = mte_to_node(enode); // Updated in the above call. | |
54a611b6 LH |
5305 | do { |
5306 | enum maple_type type; | |
5307 | unsigned char offset; | |
5308 | struct maple_enode *parent, *tmp; | |
5309 | ||
790e1fa8 | 5310 | node->slot_len = mte_dead_leaves(enode, mt, slots); |
54a611b6 LH |
5311 | if (free) |
5312 | mt_free_bulk(node->slot_len, slots); | |
5313 | offset = node->parent_slot + 1; | |
790e1fa8 LH |
5314 | enode = node->piv_parent; |
5315 | if (mte_to_node(enode) == node) | |
5316 | goto free_leaf; | |
54a611b6 | 5317 | |
790e1fa8 LH |
5318 | type = mte_node_type(enode); |
5319 | slots = ma_slots(mte_to_node(enode), type); | |
54a611b6 LH |
5320 | if (offset >= mt_slots[type]) |
5321 | goto next; | |
5322 | ||
790e1fa8 | 5323 | tmp = mt_slot_locked(mt, slots, offset); |
54a611b6 | 5324 | if (mte_node_type(tmp) && mte_to_node(tmp)) { |
790e1fa8 LH |
5325 | parent = enode; |
5326 | enode = tmp; | |
5327 | slots = mte_destroy_descend(&enode, mt, parent, offset); | |
54a611b6 LH |
5328 | } |
5329 | next: | |
790e1fa8 LH |
5330 | node = mte_to_node(enode); |
5331 | } while (start != enode); | |
54a611b6 | 5332 | |
790e1fa8 LH |
5333 | node = mte_to_node(enode); |
5334 | node->slot_len = mte_dead_leaves(enode, mt, slots); | |
54a611b6 LH |
5335 | if (free) |
5336 | mt_free_bulk(node->slot_len, slots); | |
5337 | ||
54a611b6 LH |
5338 | free_leaf: |
5339 | if (free) | |
5340 | mt_free_rcu(&node->rcu); | |
2e5b4921 | 5341 | else |
790e1fa8 | 5342 | mt_clear_meta(mt, node, node->type); |
54a611b6 LH |
5343 | } |
5344 | ||
5345 | /* | |
5346 | * mte_destroy_walk() - Free a tree or sub-tree. | |
f942b0f0 VY |
5347 | * @enode: the encoded maple node (maple_enode) to start |
5348 | * @mt: the tree to free - needed for node types. | |
54a611b6 LH |
5349 | * |
5350 | * Must hold the write lock. | |
5351 | */ | |
5352 | static inline void mte_destroy_walk(struct maple_enode *enode, | |
5353 | struct maple_tree *mt) | |
5354 | { | |
5355 | struct maple_node *node = mte_to_node(enode); | |
5356 | ||
5357 | if (mt_in_rcu(mt)) { | |
790e1fa8 | 5358 | mt_destroy_walk(enode, mt, false); |
54a611b6 LH |
5359 | call_rcu(&node->rcu, mt_free_walk); |
5360 | } else { | |
790e1fa8 | 5361 | mt_destroy_walk(enode, mt, true); |
54a611b6 LH |
5362 | } |
5363 | } | |
5364 | ||
5365 | static void mas_wr_store_setup(struct ma_wr_state *wr_mas) | |
5366 | { | |
a8091f03 LH |
5367 | if (!mas_is_active(wr_mas->mas)) { |
5368 | if (mas_is_start(wr_mas->mas)) | |
5369 | return; | |
fec29364 | 5370 | |
a8091f03 LH |
5371 | if (unlikely(mas_is_paused(wr_mas->mas))) |
5372 | goto reset; | |
1202700c | 5373 | |
a8091f03 LH |
5374 | if (unlikely(mas_is_none(wr_mas->mas))) |
5375 | goto reset; | |
5376 | ||
5377 | if (unlikely(mas_is_overflow(wr_mas->mas))) | |
5378 | goto reset; | |
5379 | ||
5380 | if (unlikely(mas_is_underflow(wr_mas->mas))) | |
5381 | goto reset; | |
5382 | } | |
fec29364 LH |
5383 | |
5384 | /* | |
5385 | * A less strict version of mas_is_span_wr() where we allow spanning | |
5386 | * writes within this node. This is to stop partial walks in | |
5387 | * mas_prealloc() from being reset. | |
5388 | */ | |
5389 | if (wr_mas->mas->last > wr_mas->mas->max) | |
5390 | goto reset; | |
5391 | ||
5392 | if (wr_mas->entry) | |
5393 | return; | |
5394 | ||
5395 | if (mte_is_leaf(wr_mas->mas->node) && | |
5396 | wr_mas->mas->last == wr_mas->mas->max) | |
5397 | goto reset; | |
5398 | ||
5399 | return; | |
5400 | ||
5401 | reset: | |
5402 | mas_reset(wr_mas->mas); | |
54a611b6 LH |
5403 | } |
5404 | ||
5405 | /* Interface */ | |
5406 | ||
5407 | /** | |
5408 | * mas_store() - Store an @entry. | |
5409 | * @mas: The maple state. | |
5410 | * @entry: The entry to store. | |
5411 | * | |
5412 | * The @mas->index and @mas->last is used to set the range for the @entry. | |
5413 | * Note: The @mas should have pre-allocated entries to ensure there is memory to | |
5414 | * store the entry. Please see mas_expected_entries()/mas_destroy() for more details. | |
5415 | * | |
5416 | * Return: the first entry between mas->index and mas->last or %NULL. | |
5417 | */ | |
5418 | void *mas_store(struct ma_state *mas, void *entry) | |
5419 | { | |
5420 | MA_WR_STATE(wr_mas, mas, entry); | |
5421 | ||
5422 | trace_ma_write(__func__, mas, 0, entry); | |
5423 | #ifdef CONFIG_DEBUG_MAPLE_TREE | |
e6d6792a | 5424 | if (MAS_WARN_ON(mas, mas->index > mas->last)) |
89f499f3 | 5425 | pr_err("Error %lX > %lX %p\n", mas->index, mas->last, entry); |
e6d6792a | 5426 | |
54a611b6 LH |
5427 | if (mas->index > mas->last) { |
5428 | mas_set_err(mas, -EINVAL); | |
5429 | return NULL; | |
5430 | } | |
5431 | ||
5432 | #endif | |
5433 | ||
5434 | /* | |
5435 | * Storing is the same operation as insert with the added caveat that it | |
5436 | * can overwrite entries. Although this seems simple enough, one may | |
5437 | * want to examine what happens if a single store operation was to | |
5438 | * overwrite multiple entries within a self-balancing B-Tree. | |
5439 | */ | |
5440 | mas_wr_store_setup(&wr_mas); | |
5441 | mas_wr_store_entry(&wr_mas); | |
5442 | return wr_mas.content; | |
5443 | } | |
120b1162 | 5444 | EXPORT_SYMBOL_GPL(mas_store); |
54a611b6 LH |
5445 | |
5446 | /** | |
5447 | * mas_store_gfp() - Store a value into the tree. | |
5448 | * @mas: The maple state | |
5449 | * @entry: The entry to store | |
5450 | * @gfp: The GFP_FLAGS to use for allocations if necessary. | |
5451 | * | |
5452 | * Return: 0 on success, -EINVAL on invalid request, -ENOMEM if memory could not | |
5453 | * be allocated. | |
5454 | */ | |
5455 | int mas_store_gfp(struct ma_state *mas, void *entry, gfp_t gfp) | |
5456 | { | |
5457 | MA_WR_STATE(wr_mas, mas, entry); | |
5458 | ||
5459 | mas_wr_store_setup(&wr_mas); | |
5460 | trace_ma_write(__func__, mas, 0, entry); | |
5461 | retry: | |
5462 | mas_wr_store_entry(&wr_mas); | |
5463 | if (unlikely(mas_nomem(mas, gfp))) | |
5464 | goto retry; | |
5465 | ||
5466 | if (unlikely(mas_is_err(mas))) | |
5467 | return xa_err(mas->node); | |
5468 | ||
5469 | return 0; | |
5470 | } | |
120b1162 | 5471 | EXPORT_SYMBOL_GPL(mas_store_gfp); |
54a611b6 LH |
5472 | |
5473 | /** | |
5474 | * mas_store_prealloc() - Store a value into the tree using memory | |
5475 | * preallocated in the maple state. | |
5476 | * @mas: The maple state | |
5477 | * @entry: The entry to store. | |
5478 | */ | |
5479 | void mas_store_prealloc(struct ma_state *mas, void *entry) | |
5480 | { | |
5481 | MA_WR_STATE(wr_mas, mas, entry); | |
5482 | ||
5483 | mas_wr_store_setup(&wr_mas); | |
5484 | trace_ma_write(__func__, mas, 0, entry); | |
5485 | mas_wr_store_entry(&wr_mas); | |
1c414c6a | 5486 | MAS_WR_BUG_ON(&wr_mas, mas_is_err(mas)); |
54a611b6 LH |
5487 | mas_destroy(mas); |
5488 | } | |
120b1162 | 5489 | EXPORT_SYMBOL_GPL(mas_store_prealloc); |
54a611b6 LH |
5490 | |
5491 | /** | |
5492 | * mas_preallocate() - Preallocate enough nodes for a store operation | |
5493 | * @mas: The maple state | |
da089254 | 5494 | * @entry: The entry that will be stored |
54a611b6 LH |
5495 | * @gfp: The GFP_FLAGS to use for allocations. |
5496 | * | |
5497 | * Return: 0 on success, -ENOMEM if memory could not be allocated. | |
5498 | */ | |
da089254 | 5499 | int mas_preallocate(struct ma_state *mas, void *entry, gfp_t gfp) |
54a611b6 | 5500 | { |
17983dc6 LH |
5501 | MA_WR_STATE(wr_mas, mas, entry); |
5502 | unsigned char node_size; | |
5503 | int request = 1; | |
54a611b6 LH |
5504 | int ret; |
5505 | ||
17983dc6 LH |
5506 | |
5507 | if (unlikely(!mas->index && mas->last == ULONG_MAX)) | |
5508 | goto ask_now; | |
5509 | ||
5510 | mas_wr_store_setup(&wr_mas); | |
5511 | wr_mas.content = mas_start(mas); | |
5512 | /* Root expand */ | |
5513 | if (unlikely(mas_is_none(mas) || mas_is_ptr(mas))) | |
5514 | goto ask_now; | |
5515 | ||
5516 | if (unlikely(!mas_wr_walk(&wr_mas))) { | |
5517 | /* Spanning store, use worst case for now */ | |
5518 | request = 1 + mas_mt_height(mas) * 3; | |
5519 | goto ask_now; | |
5520 | } | |
5521 | ||
5522 | /* At this point, we are at the leaf node that needs to be altered. */ | |
5523 | /* Exact fit, no nodes needed. */ | |
5524 | if (wr_mas.r_min == mas->index && wr_mas.r_max == mas->last) | |
5525 | return 0; | |
5526 | ||
5527 | mas_wr_end_piv(&wr_mas); | |
5528 | node_size = mas_wr_new_end(&wr_mas); | |
4249f13c SK |
5529 | |
5530 | /* Slot store, does not require additional nodes */ | |
5143eecd | 5531 | if (node_size == mas->end) { |
4249f13c SK |
5532 | /* reuse node */ |
5533 | if (!mt_in_rcu(mas->tree)) | |
5534 | return 0; | |
5535 | /* shifting boundary */ | |
5536 | if (wr_mas.offset_end - mas->offset == 1) | |
5537 | return 0; | |
5538 | } | |
5539 | ||
17983dc6 LH |
5540 | if (node_size >= mt_slots[wr_mas.type]) { |
5541 | /* Split, worst case for now. */ | |
5542 | request = 1 + mas_mt_height(mas) * 2; | |
5543 | goto ask_now; | |
5544 | } | |
5545 | ||
d5f6057c | 5546 | /* New root needs a single node */ |
17983dc6 LH |
5547 | if (unlikely(mte_is_root(mas->node))) |
5548 | goto ask_now; | |
5549 | ||
5550 | /* Potential spanning rebalance collapsing a node, use worst-case */ | |
5551 | if (node_size - 1 <= mt_min_slots[wr_mas.type]) | |
5552 | request = mas_mt_height(mas) * 2 - 1; | |
5553 | ||
5554 | /* node store, slot store needs one node */ | |
5555 | ask_now: | |
5556 | mas_node_count_gfp(mas, request, gfp); | |
54a611b6 LH |
5557 | mas->mas_flags |= MA_STATE_PREALLOC; |
5558 | if (likely(!mas_is_err(mas))) | |
5559 | return 0; | |
5560 | ||
5561 | mas_set_alloc_req(mas, 0); | |
5562 | ret = xa_err(mas->node); | |
5563 | mas_reset(mas); | |
5564 | mas_destroy(mas); | |
5565 | mas_reset(mas); | |
5566 | return ret; | |
5567 | } | |
5c63a7c3 | 5568 | EXPORT_SYMBOL_GPL(mas_preallocate); |
54a611b6 LH |
5569 | |
5570 | /* | |
5571 | * mas_destroy() - destroy a maple state. | |
5572 | * @mas: The maple state | |
5573 | * | |
5574 | * Upon completion, check the left-most node and rebalance against the node to | |
5575 | * the right if necessary. Frees any allocated nodes associated with this maple | |
5576 | * state. | |
5577 | */ | |
5578 | void mas_destroy(struct ma_state *mas) | |
5579 | { | |
5580 | struct maple_alloc *node; | |
541e06b7 | 5581 | unsigned long total; |
54a611b6 LH |
5582 | |
5583 | /* | |
5584 | * When using mas_for_each() to insert an expected number of elements, | |
5585 | * it is possible that the number inserted is less than the expected | |
5586 | * number. To fix an invalid final node, a check is performed here to | |
5587 | * rebalance the previous node with the final node. | |
5588 | */ | |
5589 | if (mas->mas_flags & MA_STATE_REBALANCE) { | |
5590 | unsigned char end; | |
5591 | ||
23e734ec | 5592 | mas_start(mas); |
54a611b6 | 5593 | mtree_range_walk(mas); |
1f41ef12 | 5594 | end = mas->end + 1; |
54a611b6 LH |
5595 | if (end < mt_min_slot_count(mas->node) - 1) |
5596 | mas_destroy_rebalance(mas, end); | |
5597 | ||
5598 | mas->mas_flags &= ~MA_STATE_REBALANCE; | |
5599 | } | |
5600 | mas->mas_flags &= ~(MA_STATE_BULK|MA_STATE_PREALLOC); | |
5601 | ||
541e06b7 LH |
5602 | total = mas_allocated(mas); |
5603 | while (total) { | |
54a611b6 LH |
5604 | node = mas->alloc; |
5605 | mas->alloc = node->slot[0]; | |
541e06b7 LH |
5606 | if (node->node_count > 1) { |
5607 | size_t count = node->node_count - 1; | |
5608 | ||
5609 | mt_free_bulk(count, (void __rcu **)&node->slot[1]); | |
5610 | total -= count; | |
5611 | } | |
4f2267b5 | 5612 | mt_free_one(ma_mnode_ptr(node)); |
541e06b7 | 5613 | total--; |
54a611b6 | 5614 | } |
541e06b7 | 5615 | |
54a611b6 LH |
5616 | mas->alloc = NULL; |
5617 | } | |
120b1162 | 5618 | EXPORT_SYMBOL_GPL(mas_destroy); |
54a611b6 LH |
5619 | |
5620 | /* | |
5621 | * mas_expected_entries() - Set the expected number of entries that will be inserted. | |
5622 | * @mas: The maple state | |
5623 | * @nr_entries: The number of expected entries. | |
5624 | * | |
5625 | * This will attempt to pre-allocate enough nodes to store the expected number | |
5626 | * of entries. The allocations will occur using the bulk allocator interface | |
5627 | * for speed. Please call mas_destroy() on the @mas after inserting the entries | |
5628 | * to ensure any unused nodes are freed. | |
5629 | * | |
5630 | * Return: 0 on success, -ENOMEM if memory could not be allocated. | |
5631 | */ | |
5632 | int mas_expected_entries(struct ma_state *mas, unsigned long nr_entries) | |
5633 | { | |
5634 | int nonleaf_cap = MAPLE_ARANGE64_SLOTS - 2; | |
5635 | struct maple_enode *enode = mas->node; | |
5636 | int nr_nodes; | |
5637 | int ret; | |
5638 | ||
5639 | /* | |
5640 | * Sometimes it is necessary to duplicate a tree to a new tree, such as | |
5641 | * forking a process and duplicating the VMAs from one tree to a new | |
5642 | * tree. When such a situation arises, it is known that the new tree is | |
5643 | * not going to be used until the entire tree is populated. For | |
5644 | * performance reasons, it is best to use a bulk load with RCU disabled. | |
5645 | * This allows for optimistic splitting that favours the left and reuse | |
5646 | * of nodes during the operation. | |
5647 | */ | |
5648 | ||
5649 | /* Optimize splitting for bulk insert in-order */ | |
5650 | mas->mas_flags |= MA_STATE_BULK; | |
5651 | ||
5652 | /* | |
5653 | * Avoid overflow, assume a gap between each entry and a trailing null. | |
5654 | * If this is wrong, it just means allocation can happen during | |
5655 | * insertion of entries. | |
5656 | */ | |
5657 | nr_nodes = max(nr_entries, nr_entries * 2 + 1); | |
5658 | if (!mt_is_alloc(mas->tree)) | |
5659 | nonleaf_cap = MAPLE_RANGE64_SLOTS - 2; | |
5660 | ||
5661 | /* Leaves; reduce slots to keep space for expansion */ | |
5662 | nr_nodes = DIV_ROUND_UP(nr_nodes, MAPLE_RANGE64_SLOTS - 2); | |
5663 | /* Internal nodes */ | |
5664 | nr_nodes += DIV_ROUND_UP(nr_nodes, nonleaf_cap); | |
5665 | /* Add working room for split (2 nodes) + new parents */ | |
099d7439 | 5666 | mas_node_count_gfp(mas, nr_nodes + 3, GFP_KERNEL); |
54a611b6 LH |
5667 | |
5668 | /* Detect if allocations run out */ | |
5669 | mas->mas_flags |= MA_STATE_PREALLOC; | |
5670 | ||
5671 | if (!mas_is_err(mas)) | |
5672 | return 0; | |
5673 | ||
5674 | ret = xa_err(mas->node); | |
5675 | mas->node = enode; | |
5676 | mas_destroy(mas); | |
5677 | return ret; | |
5678 | ||
5679 | } | |
120b1162 | 5680 | EXPORT_SYMBOL_GPL(mas_expected_entries); |
54a611b6 | 5681 | |
271f61a8 | 5682 | static bool mas_next_setup(struct ma_state *mas, unsigned long max, |
6169b553 | 5683 | void **entry) |
54a611b6 | 5684 | { |
ca80f610 LH |
5685 | bool was_none = mas_is_none(mas); |
5686 | ||
a8091f03 | 5687 | if (unlikely(mas->last >= max)) { |
067311d3 | 5688 | mas->status = ma_overflow; |
a8091f03 LH |
5689 | return true; |
5690 | } | |
5691 | ||
067311d3 LH |
5692 | switch (mas->status) { |
5693 | case ma_active: | |
a8091f03 | 5694 | return false; |
067311d3 LH |
5695 | case ma_none: |
5696 | fallthrough; | |
5697 | case ma_pause: | |
5698 | mas->status = ma_start; | |
5699 | fallthrough; | |
5700 | case ma_start: | |
5701 | mas_walk(mas); /* Retries on dead nodes handled by mas_walk */ | |
5702 | break; | |
5703 | case ma_overflow: | |
a8091f03 | 5704 | /* Overflowed before, but the max changed */ |
067311d3 LH |
5705 | mas->status = ma_active; |
5706 | break; | |
5707 | case ma_underflow: | |
5708 | /* The user expects the mas to be one before where it is */ | |
5709 | mas->status = ma_active; | |
a8091f03 LH |
5710 | *entry = mas_walk(mas); |
5711 | if (*entry) | |
5712 | return true; | |
067311d3 LH |
5713 | break; |
5714 | case ma_root: | |
5715 | break; | |
5716 | case ma_error: | |
5717 | return true; | |
a8091f03 | 5718 | } |
54a611b6 | 5719 | |
067311d3 LH |
5720 | if (likely(mas_is_active(mas))) /* Fast path */ |
5721 | return false; | |
54a611b6 LH |
5722 | |
5723 | if (mas_is_ptr(mas)) { | |
6169b553 | 5724 | *entry = NULL; |
ca80f610 LH |
5725 | if (was_none && mas->index == 0) { |
5726 | mas->index = mas->last = 0; | |
6169b553 | 5727 | return true; |
54a611b6 | 5728 | } |
ca80f610 LH |
5729 | mas->index = 1; |
5730 | mas->last = ULONG_MAX; | |
067311d3 | 5731 | mas->status = ma_none; |
6169b553 | 5732 | return true; |
54a611b6 LH |
5733 | } |
5734 | ||
6169b553 LH |
5735 | if (mas_is_none(mas)) |
5736 | return true; | |
a8091f03 | 5737 | |
6169b553 LH |
5738 | return false; |
5739 | } | |
5740 | ||
5741 | /** | |
5742 | * mas_next() - Get the next entry. | |
5743 | * @mas: The maple state | |
5744 | * @max: The maximum index to check. | |
5745 | * | |
5746 | * Returns the next entry after @mas->index. | |
5747 | * Must hold rcu_read_lock or the write lock. | |
5748 | * Can return the zero entry. | |
5749 | * | |
5750 | * Return: The next entry or %NULL | |
5751 | */ | |
5752 | void *mas_next(struct ma_state *mas, unsigned long max) | |
5753 | { | |
5754 | void *entry = NULL; | |
5755 | ||
5756 | if (mas_next_setup(mas, max, &entry)) | |
5757 | return entry; | |
5758 | ||
5759 | /* Retries on dead nodes handled by mas_next_slot */ | |
067311d3 | 5760 | return mas_next_slot(mas, max, false); |
54a611b6 LH |
5761 | } |
5762 | EXPORT_SYMBOL_GPL(mas_next); | |
5763 | ||
6169b553 LH |
5764 | /** |
5765 | * mas_next_range() - Advance the maple state to the next range | |
5766 | * @mas: The maple state | |
5767 | * @max: The maximum index to check. | |
5768 | * | |
5769 | * Sets @mas->index and @mas->last to the range. | |
5770 | * Must hold rcu_read_lock or the write lock. | |
5771 | * Can return the zero entry. | |
5772 | * | |
5773 | * Return: The next entry or %NULL | |
5774 | */ | |
5775 | void *mas_next_range(struct ma_state *mas, unsigned long max) | |
5776 | { | |
5777 | void *entry = NULL; | |
5778 | ||
5779 | if (mas_next_setup(mas, max, &entry)) | |
5780 | return entry; | |
5781 | ||
5782 | /* Retries on dead nodes handled by mas_next_slot */ | |
067311d3 | 5783 | return mas_next_slot(mas, max, true); |
6169b553 LH |
5784 | } |
5785 | EXPORT_SYMBOL_GPL(mas_next_range); | |
5786 | ||
54a611b6 LH |
5787 | /** |
5788 | * mt_next() - get the next value in the maple tree | |
5789 | * @mt: The maple tree | |
5790 | * @index: The start index | |
5791 | * @max: The maximum index to check | |
5792 | * | |
fad9c80e TG |
5793 | * Takes RCU read lock internally to protect the search, which does not |
5794 | * protect the returned pointer after dropping RCU read lock. | |
5795 | * See also: Documentation/core-api/maple_tree.rst | |
5796 | * | |
5797 | * Return: The entry higher than @index or %NULL if nothing is found. | |
54a611b6 LH |
5798 | */ |
5799 | void *mt_next(struct maple_tree *mt, unsigned long index, unsigned long max) | |
5800 | { | |
5801 | void *entry = NULL; | |
5802 | MA_STATE(mas, mt, index, index); | |
5803 | ||
5804 | rcu_read_lock(); | |
5805 | entry = mas_next(&mas, max); | |
5806 | rcu_read_unlock(); | |
5807 | return entry; | |
5808 | } | |
5809 | EXPORT_SYMBOL_GPL(mt_next); | |
5810 | ||
271f61a8 | 5811 | static bool mas_prev_setup(struct ma_state *mas, unsigned long min, void **entry) |
54a611b6 | 5812 | { |
a8091f03 | 5813 | if (unlikely(mas->index <= min)) { |
067311d3 | 5814 | mas->status = ma_underflow; |
a8091f03 LH |
5815 | return true; |
5816 | } | |
54a611b6 | 5817 | |
067311d3 LH |
5818 | switch (mas->status) { |
5819 | case ma_active: | |
a8091f03 | 5820 | return false; |
067311d3 LH |
5821 | case ma_start: |
5822 | break; | |
5823 | case ma_none: | |
5824 | fallthrough; | |
5825 | case ma_pause: | |
5826 | mas->status = ma_start; | |
5827 | break; | |
5828 | case ma_underflow: | |
5829 | /* underflowed before but the min changed */ | |
5830 | mas->status = ma_active; | |
5831 | break; | |
5832 | case ma_overflow: | |
5833 | /* User expects mas to be one after where it is */ | |
5834 | mas->status = ma_active; | |
a8091f03 LH |
5835 | *entry = mas_walk(mas); |
5836 | if (*entry) | |
5837 | return true; | |
067311d3 LH |
5838 | break; |
5839 | case ma_root: | |
5840 | break; | |
5841 | case ma_error: | |
5842 | return true; | |
54a611b6 LH |
5843 | } |
5844 | ||
a8091f03 LH |
5845 | if (mas_is_start(mas)) |
5846 | mas_walk(mas); | |
5847 | ||
39193685 | 5848 | if (unlikely(mas_is_ptr(mas))) { |
067311d3 LH |
5849 | if (!mas->index) { |
5850 | mas->status = ma_none; | |
5851 | return true; | |
5852 | } | |
54a611b6 | 5853 | mas->index = mas->last = 0; |
6b9e93e0 LH |
5854 | *entry = mas_root(mas); |
5855 | return true; | |
39193685 LH |
5856 | } |
5857 | ||
5858 | if (mas_is_none(mas)) { | |
5859 | if (mas->index) { | |
5860 | /* Walked to out-of-range pointer? */ | |
5861 | mas->index = mas->last = 0; | |
067311d3 | 5862 | mas->status = ma_root; |
6b9e93e0 LH |
5863 | *entry = mas_root(mas); |
5864 | return true; | |
39193685 | 5865 | } |
6b9e93e0 | 5866 | return true; |
54a611b6 | 5867 | } |
6b9e93e0 LH |
5868 | |
5869 | return false; | |
6b9e93e0 LH |
5870 | } |
5871 | ||
5872 | /** | |
5873 | * mas_prev() - Get the previous entry | |
5874 | * @mas: The maple state | |
5875 | * @min: The minimum value to check. | |
5876 | * | |
5877 | * Must hold rcu_read_lock or the write lock. | |
067311d3 | 5878 | * Will reset mas to ma_start if the status is ma_none. Will stop on not |
6b9e93e0 LH |
5879 | * searchable nodes. |
5880 | * | |
5881 | * Return: the previous value or %NULL. | |
5882 | */ | |
5883 | void *mas_prev(struct ma_state *mas, unsigned long min) | |
5884 | { | |
5885 | void *entry = NULL; | |
5886 | ||
5887 | if (mas_prev_setup(mas, min, &entry)) | |
5888 | return entry; | |
5889 | ||
067311d3 | 5890 | return mas_prev_slot(mas, min, false); |
54a611b6 LH |
5891 | } |
5892 | EXPORT_SYMBOL_GPL(mas_prev); | |
5893 | ||
6b9e93e0 LH |
5894 | /** |
5895 | * mas_prev_range() - Advance to the previous range | |
5896 | * @mas: The maple state | |
5897 | * @min: The minimum value to check. | |
5898 | * | |
5899 | * Sets @mas->index and @mas->last to the range. | |
5900 | * Must hold rcu_read_lock or the write lock. | |
067311d3 | 5901 | * Will reset mas to ma_start if the node is ma_none. Will stop on not |
6b9e93e0 LH |
5902 | * searchable nodes. |
5903 | * | |
5904 | * Return: the previous value or %NULL. | |
5905 | */ | |
5906 | void *mas_prev_range(struct ma_state *mas, unsigned long min) | |
5907 | { | |
5908 | void *entry = NULL; | |
5909 | ||
5910 | if (mas_prev_setup(mas, min, &entry)) | |
5911 | return entry; | |
5912 | ||
067311d3 | 5913 | return mas_prev_slot(mas, min, true); |
6b9e93e0 LH |
5914 | } |
5915 | EXPORT_SYMBOL_GPL(mas_prev_range); | |
5916 | ||
54a611b6 LH |
5917 | /** |
5918 | * mt_prev() - get the previous value in the maple tree | |
5919 | * @mt: The maple tree | |
5920 | * @index: The start index | |
5921 | * @min: The minimum index to check | |
5922 | * | |
fad9c80e TG |
5923 | * Takes RCU read lock internally to protect the search, which does not |
5924 | * protect the returned pointer after dropping RCU read lock. | |
5925 | * See also: Documentation/core-api/maple_tree.rst | |
5926 | * | |
5927 | * Return: The entry before @index or %NULL if nothing is found. | |
54a611b6 LH |
5928 | */ |
5929 | void *mt_prev(struct maple_tree *mt, unsigned long index, unsigned long min) | |
5930 | { | |
5931 | void *entry = NULL; | |
5932 | MA_STATE(mas, mt, index, index); | |
5933 | ||
5934 | rcu_read_lock(); | |
5935 | entry = mas_prev(&mas, min); | |
5936 | rcu_read_unlock(); | |
5937 | return entry; | |
5938 | } | |
5939 | EXPORT_SYMBOL_GPL(mt_prev); | |
5940 | ||
5941 | /** | |
5942 | * mas_pause() - Pause a mas_find/mas_for_each to drop the lock. | |
5943 | * @mas: The maple state to pause | |
5944 | * | |
5945 | * Some users need to pause a walk and drop the lock they're holding in | |
5946 | * order to yield to a higher priority thread or carry out an operation | |
5947 | * on an entry. Those users should call this function before they drop | |
5948 | * the lock. It resets the @mas to be suitable for the next iteration | |
5949 | * of the loop after the user has reacquired the lock. If most entries | |
5950 | * found during a walk require you to call mas_pause(), the mt_for_each() | |
5951 | * iterator may be more appropriate. | |
5952 | * | |
5953 | */ | |
5954 | void mas_pause(struct ma_state *mas) | |
5955 | { | |
067311d3 LH |
5956 | mas->status = ma_pause; |
5957 | mas->node = NULL; | |
54a611b6 LH |
5958 | } |
5959 | EXPORT_SYMBOL_GPL(mas_pause); | |
5960 | ||
5961 | /** | |
6169b553 | 5962 | * mas_find_setup() - Internal function to set up mas_find*(). |
54a611b6 | 5963 | * @mas: The maple state |
6169b553 LH |
5964 | * @max: The maximum index |
5965 | * @entry: Pointer to the entry | |
54a611b6 | 5966 | * |
6169b553 | 5967 | * Returns: True if entry is the answer, false otherwise. |
54a611b6 | 5968 | */ |
271f61a8 | 5969 | static __always_inline bool mas_find_setup(struct ma_state *mas, unsigned long max, void **entry) |
54a611b6 | 5970 | { |
067311d3 LH |
5971 | switch (mas->status) { |
5972 | case ma_active: | |
a8091f03 LH |
5973 | if (mas->last < max) |
5974 | return false; | |
a8091f03 | 5975 | return true; |
067311d3 LH |
5976 | case ma_start: |
5977 | break; | |
5978 | case ma_pause: | |
ca80f610 | 5979 | if (unlikely(mas->last >= max)) |
6169b553 | 5980 | return true; |
ca80f610 | 5981 | |
a8091f03 | 5982 | mas->index = ++mas->last; |
067311d3 LH |
5983 | mas->status = ma_start; |
5984 | break; | |
5985 | case ma_none: | |
ca80f610 | 5986 | if (unlikely(mas->last >= max)) |
6169b553 | 5987 | return true; |
ca80f610 | 5988 | |
a8091f03 | 5989 | mas->index = mas->last; |
067311d3 LH |
5990 | mas->status = ma_start; |
5991 | break; | |
5992 | case ma_underflow: | |
5993 | /* mas is pointing at entry before unable to go lower */ | |
5994 | if (unlikely(mas->index >= max)) { | |
5995 | mas->status = ma_overflow; | |
a8091f03 LH |
5996 | return true; |
5997 | } | |
17dc622c | 5998 | |
067311d3 LH |
5999 | mas->status = ma_active; |
6000 | *entry = mas_walk(mas); | |
6001 | if (*entry) | |
6002 | return true; | |
6003 | break; | |
6004 | case ma_overflow: | |
6005 | if (unlikely(mas->last >= max)) | |
6006 | return true; | |
6007 | ||
6008 | mas->status = ma_active; | |
6009 | *entry = mas_walk(mas); | |
6010 | if (*entry) | |
6011 | return true; | |
6012 | break; | |
6013 | case ma_root: | |
6014 | break; | |
6015 | case ma_error: | |
6016 | return true; | |
a8091f03 LH |
6017 | } |
6018 | ||
6019 | if (mas_is_start(mas)) { | |
54a611b6 | 6020 | /* First run or continue */ |
54a611b6 | 6021 | if (mas->index > max) |
6169b553 | 6022 | return true; |
54a611b6 | 6023 | |
6169b553 LH |
6024 | *entry = mas_walk(mas); |
6025 | if (*entry) | |
6026 | return true; | |
ca80f610 | 6027 | |
54a611b6 LH |
6028 | } |
6029 | ||
9a40d45c LH |
6030 | if (unlikely(mas_is_ptr(mas))) |
6031 | goto ptr_out_of_range; | |
ca80f610 | 6032 | |
9a40d45c | 6033 | if (unlikely(mas_is_none(mas))) |
6169b553 | 6034 | return true; |
ca80f610 LH |
6035 | |
6036 | if (mas->index == max) | |
6169b553 | 6037 | return true; |
54a611b6 | 6038 | |
6169b553 | 6039 | return false; |
ca80f610 LH |
6040 | |
6041 | ptr_out_of_range: | |
067311d3 | 6042 | mas->status = ma_none; |
ca80f610 LH |
6043 | mas->index = 1; |
6044 | mas->last = ULONG_MAX; | |
6169b553 LH |
6045 | return true; |
6046 | } | |
6047 | ||
6048 | /** | |
6049 | * mas_find() - On the first call, find the entry at or after mas->index up to | |
6050 | * %max. Otherwise, find the entry after mas->index. | |
6051 | * @mas: The maple state | |
6052 | * @max: The maximum value to check. | |
6053 | * | |
6054 | * Must hold rcu_read_lock or the write lock. | |
6055 | * If an entry exists, last and index are updated accordingly. | |
067311d3 | 6056 | * May set @mas->status to ma_overflow. |
6169b553 LH |
6057 | * |
6058 | * Return: The entry or %NULL. | |
6059 | */ | |
6060 | void *mas_find(struct ma_state *mas, unsigned long max) | |
6061 | { | |
6062 | void *entry = NULL; | |
6063 | ||
6064 | if (mas_find_setup(mas, max, &entry)) | |
6065 | return entry; | |
6066 | ||
6067 | /* Retries on dead nodes handled by mas_next_slot */ | |
067311d3 LH |
6068 | entry = mas_next_slot(mas, max, false); |
6069 | /* Ignore overflow */ | |
6070 | mas->status = ma_active; | |
6071 | return entry; | |
54a611b6 | 6072 | } |
120b1162 | 6073 | EXPORT_SYMBOL_GPL(mas_find); |
54a611b6 | 6074 | |
6169b553 LH |
6075 | /** |
6076 | * mas_find_range() - On the first call, find the entry at or after | |
6077 | * mas->index up to %max. Otherwise, advance to the next slot mas->index. | |
6078 | * @mas: The maple state | |
6079 | * @max: The maximum value to check. | |
6080 | * | |
6081 | * Must hold rcu_read_lock or the write lock. | |
6082 | * If an entry exists, last and index are updated accordingly. | |
067311d3 | 6083 | * May set @mas->status to ma_overflow. |
6169b553 LH |
6084 | * |
6085 | * Return: The entry or %NULL. | |
6086 | */ | |
6087 | void *mas_find_range(struct ma_state *mas, unsigned long max) | |
6088 | { | |
a8091f03 | 6089 | void *entry = NULL; |
6169b553 LH |
6090 | |
6091 | if (mas_find_setup(mas, max, &entry)) | |
6092 | return entry; | |
6093 | ||
6094 | /* Retries on dead nodes handled by mas_next_slot */ | |
067311d3 | 6095 | return mas_next_slot(mas, max, true); |
6169b553 LH |
6096 | } |
6097 | EXPORT_SYMBOL_GPL(mas_find_range); | |
6098 | ||
54a611b6 | 6099 | /** |
6b9e93e0 | 6100 | * mas_find_rev_setup() - Internal function to set up mas_find_*_rev() |
54a611b6 | 6101 | * @mas: The maple state |
6b9e93e0 LH |
6102 | * @min: The minimum index |
6103 | * @entry: Pointer to the entry | |
54a611b6 | 6104 | * |
6b9e93e0 | 6105 | * Returns: True if entry is the answer, false otherwise. |
54a611b6 | 6106 | */ |
271f61a8 | 6107 | static bool mas_find_rev_setup(struct ma_state *mas, unsigned long min, |
6b9e93e0 | 6108 | void **entry) |
54a611b6 | 6109 | { |
39193685 | 6110 | |
067311d3 LH |
6111 | switch (mas->status) { |
6112 | case ma_active: | |
6113 | goto active; | |
6114 | case ma_start: | |
6115 | break; | |
6116 | case ma_pause: | |
39193685 | 6117 | if (unlikely(mas->index <= min)) { |
067311d3 | 6118 | mas->status = ma_underflow; |
6b9e93e0 | 6119 | return true; |
54a611b6 | 6120 | } |
54a611b6 | 6121 | mas->last = --mas->index; |
067311d3 LH |
6122 | mas->status = ma_start; |
6123 | break; | |
6124 | case ma_none: | |
a8091f03 LH |
6125 | if (mas->index <= min) |
6126 | goto none; | |
6127 | ||
6128 | mas->last = mas->index; | |
067311d3 LH |
6129 | mas->status = ma_start; |
6130 | break; | |
6131 | case ma_overflow: /* user expects the mas to be one after where it is */ | |
6132 | if (unlikely(mas->index <= min)) { | |
6133 | mas->status = ma_underflow; | |
a8091f03 LH |
6134 | return true; |
6135 | } | |
6136 | ||
067311d3 LH |
6137 | mas->status = ma_active; |
6138 | break; | |
6139 | case ma_underflow: /* user expects the mas to be one before where it is */ | |
6140 | if (unlikely(mas->index <= min)) | |
6141 | return true; | |
6142 | ||
6143 | mas->status = ma_active; | |
6144 | break; | |
6145 | case ma_root: | |
6146 | break; | |
6147 | case ma_error: | |
6148 | return true; | |
54a611b6 LH |
6149 | } |
6150 | ||
a8091f03 | 6151 | if (mas_is_start(mas)) { |
54a611b6 | 6152 | /* First run or continue */ |
54a611b6 | 6153 | if (mas->index < min) |
6b9e93e0 | 6154 | return true; |
54a611b6 | 6155 | |
6b9e93e0 LH |
6156 | *entry = mas_walk(mas); |
6157 | if (*entry) | |
6158 | return true; | |
54a611b6 LH |
6159 | } |
6160 | ||
9a40d45c LH |
6161 | if (unlikely(mas_is_ptr(mas))) |
6162 | goto none; | |
39193685 | 6163 | |
9a40d45c LH |
6164 | if (unlikely(mas_is_none(mas))) { |
6165 | /* | |
6166 | * Walked to the location, and there was nothing so the previous | |
6167 | * location is 0. | |
6168 | */ | |
6169 | mas->last = mas->index = 0; | |
6170 | mas->status = ma_root; | |
6171 | *entry = mas_root(mas); | |
6172 | return true; | |
39193685 | 6173 | } |
54a611b6 | 6174 | |
067311d3 | 6175 | active: |
54a611b6 | 6176 | if (mas->index < min) |
6b9e93e0 | 6177 | return true; |
54a611b6 | 6178 | |
6b9e93e0 | 6179 | return false; |
39193685 LH |
6180 | |
6181 | none: | |
067311d3 | 6182 | mas->status = ma_none; |
6b9e93e0 LH |
6183 | return true; |
6184 | } | |
6185 | ||
6186 | /** | |
6187 | * mas_find_rev: On the first call, find the first non-null entry at or below | |
6188 | * mas->index down to %min. Otherwise find the first non-null entry below | |
6189 | * mas->index down to %min. | |
6190 | * @mas: The maple state | |
6191 | * @min: The minimum value to check. | |
6192 | * | |
6193 | * Must hold rcu_read_lock or the write lock. | |
6194 | * If an entry exists, last and index are updated accordingly. | |
067311d3 | 6195 | * May set @mas->status to ma_underflow. |
6b9e93e0 LH |
6196 | * |
6197 | * Return: The entry or %NULL. | |
6198 | */ | |
6199 | void *mas_find_rev(struct ma_state *mas, unsigned long min) | |
6200 | { | |
a8091f03 | 6201 | void *entry = NULL; |
6b9e93e0 LH |
6202 | |
6203 | if (mas_find_rev_setup(mas, min, &entry)) | |
6204 | return entry; | |
6205 | ||
6206 | /* Retries on dead nodes handled by mas_prev_slot */ | |
067311d3 | 6207 | return mas_prev_slot(mas, min, false); |
6b9e93e0 | 6208 | |
54a611b6 | 6209 | } |
120b1162 | 6210 | EXPORT_SYMBOL_GPL(mas_find_rev); |
54a611b6 | 6211 | |
6b9e93e0 LH |
6212 | /** |
6213 | * mas_find_range_rev: On the first call, find the first non-null entry at or | |
6214 | * below mas->index down to %min. Otherwise advance to the previous slot after | |
6215 | * mas->index down to %min. | |
6216 | * @mas: The maple state | |
6217 | * @min: The minimum value to check. | |
6218 | * | |
6219 | * Must hold rcu_read_lock or the write lock. | |
6220 | * If an entry exists, last and index are updated accordingly. | |
067311d3 | 6221 | * May set @mas->status to ma_underflow. |
6b9e93e0 LH |
6222 | * |
6223 | * Return: The entry or %NULL. | |
6224 | */ | |
6225 | void *mas_find_range_rev(struct ma_state *mas, unsigned long min) | |
6226 | { | |
a8091f03 | 6227 | void *entry = NULL; |
6b9e93e0 LH |
6228 | |
6229 | if (mas_find_rev_setup(mas, min, &entry)) | |
6230 | return entry; | |
6231 | ||
6232 | /* Retries on dead nodes handled by mas_prev_slot */ | |
067311d3 | 6233 | return mas_prev_slot(mas, min, true); |
6b9e93e0 LH |
6234 | } |
6235 | EXPORT_SYMBOL_GPL(mas_find_range_rev); | |
6236 | ||
54a611b6 LH |
6237 | /** |
6238 | * mas_erase() - Find the range in which index resides and erase the entire | |
6239 | * range. | |
6240 | * @mas: The maple state | |
6241 | * | |
6242 | * Must hold the write lock. | |
6243 | * Searches for @mas->index, sets @mas->index and @mas->last to the range and | |
6244 | * erases that range. | |
6245 | * | |
6246 | * Return: the entry that was erased or %NULL, @mas->index and @mas->last are updated. | |
6247 | */ | |
6248 | void *mas_erase(struct ma_state *mas) | |
6249 | { | |
6250 | void *entry; | |
6251 | MA_WR_STATE(wr_mas, mas, NULL); | |
6252 | ||
f7a59018 | 6253 | if (!mas_is_active(mas) || !mas_is_start(mas)) |
067311d3 | 6254 | mas->status = ma_start; |
54a611b6 LH |
6255 | |
6256 | /* Retry unnecessary when holding the write lock. */ | |
6257 | entry = mas_state_walk(mas); | |
6258 | if (!entry) | |
6259 | return NULL; | |
6260 | ||
6261 | write_retry: | |
6262 | /* Must reset to ensure spanning writes of last slot are detected */ | |
6263 | mas_reset(mas); | |
6264 | mas_wr_store_setup(&wr_mas); | |
6265 | mas_wr_store_entry(&wr_mas); | |
6266 | if (mas_nomem(mas, GFP_KERNEL)) | |
6267 | goto write_retry; | |
6268 | ||
6269 | return entry; | |
6270 | } | |
6271 | EXPORT_SYMBOL_GPL(mas_erase); | |
6272 | ||
6273 | /** | |
6274 | * mas_nomem() - Check if there was an error allocating and do the allocation | |
6275 | * if necessary If there are allocations, then free them. | |
6276 | * @mas: The maple state | |
6277 | * @gfp: The GFP_FLAGS to use for allocations | |
6278 | * Return: true on allocation, false otherwise. | |
6279 | */ | |
6280 | bool mas_nomem(struct ma_state *mas, gfp_t gfp) | |
14c4b5ab | 6281 | __must_hold(mas->tree->ma_lock) |
54a611b6 LH |
6282 | { |
6283 | if (likely(mas->node != MA_ERROR(-ENOMEM))) { | |
6284 | mas_destroy(mas); | |
6285 | return false; | |
6286 | } | |
6287 | ||
6288 | if (gfpflags_allow_blocking(gfp) && !mt_external_lock(mas->tree)) { | |
6289 | mtree_unlock(mas->tree); | |
6290 | mas_alloc_nodes(mas, gfp); | |
6291 | mtree_lock(mas->tree); | |
6292 | } else { | |
6293 | mas_alloc_nodes(mas, gfp); | |
6294 | } | |
6295 | ||
6296 | if (!mas_allocated(mas)) | |
6297 | return false; | |
6298 | ||
067311d3 | 6299 | mas->status = ma_start; |
54a611b6 LH |
6300 | return true; |
6301 | } | |
6302 | ||
6303 | void __init maple_tree_init(void) | |
6304 | { | |
6305 | maple_node_cache = kmem_cache_create("maple_node", | |
6306 | sizeof(struct maple_node), sizeof(struct maple_node), | |
6307 | SLAB_PANIC, NULL); | |
6308 | } | |
6309 | ||
6310 | /** | |
6311 | * mtree_load() - Load a value stored in a maple tree | |
6312 | * @mt: The maple tree | |
6313 | * @index: The index to load | |
6314 | * | |
6315 | * Return: the entry or %NULL | |
6316 | */ | |
6317 | void *mtree_load(struct maple_tree *mt, unsigned long index) | |
6318 | { | |
6319 | MA_STATE(mas, mt, index, index); | |
6320 | void *entry; | |
6321 | ||
6322 | trace_ma_read(__func__, &mas); | |
6323 | rcu_read_lock(); | |
6324 | retry: | |
6325 | entry = mas_start(&mas); | |
6326 | if (unlikely(mas_is_none(&mas))) | |
6327 | goto unlock; | |
6328 | ||
6329 | if (unlikely(mas_is_ptr(&mas))) { | |
6330 | if (index) | |
6331 | entry = NULL; | |
6332 | ||
6333 | goto unlock; | |
6334 | } | |
6335 | ||
6336 | entry = mtree_lookup_walk(&mas); | |
6337 | if (!entry && unlikely(mas_is_start(&mas))) | |
6338 | goto retry; | |
6339 | unlock: | |
6340 | rcu_read_unlock(); | |
6341 | if (xa_is_zero(entry)) | |
6342 | return NULL; | |
6343 | ||
6344 | return entry; | |
6345 | } | |
6346 | EXPORT_SYMBOL(mtree_load); | |
6347 | ||
6348 | /** | |
6349 | * mtree_store_range() - Store an entry at a given range. | |
6350 | * @mt: The maple tree | |
6351 | * @index: The start of the range | |
6352 | * @last: The end of the range | |
6353 | * @entry: The entry to store | |
6354 | * @gfp: The GFP_FLAGS to use for allocations | |
6355 | * | |
6356 | * Return: 0 on success, -EINVAL on invalid request, -ENOMEM if memory could not | |
6357 | * be allocated. | |
6358 | */ | |
6359 | int mtree_store_range(struct maple_tree *mt, unsigned long index, | |
6360 | unsigned long last, void *entry, gfp_t gfp) | |
6361 | { | |
6362 | MA_STATE(mas, mt, index, last); | |
6363 | MA_WR_STATE(wr_mas, &mas, entry); | |
6364 | ||
6365 | trace_ma_write(__func__, &mas, 0, entry); | |
6366 | if (WARN_ON_ONCE(xa_is_advanced(entry))) | |
6367 | return -EINVAL; | |
6368 | ||
6369 | if (index > last) | |
6370 | return -EINVAL; | |
6371 | ||
6372 | mtree_lock(mt); | |
6373 | retry: | |
6374 | mas_wr_store_entry(&wr_mas); | |
6375 | if (mas_nomem(&mas, gfp)) | |
6376 | goto retry; | |
6377 | ||
6378 | mtree_unlock(mt); | |
6379 | if (mas_is_err(&mas)) | |
6380 | return xa_err(mas.node); | |
6381 | ||
6382 | return 0; | |
6383 | } | |
6384 | EXPORT_SYMBOL(mtree_store_range); | |
6385 | ||
6386 | /** | |
6387 | * mtree_store() - Store an entry at a given index. | |
6388 | * @mt: The maple tree | |
6389 | * @index: The index to store the value | |
6390 | * @entry: The entry to store | |
6391 | * @gfp: The GFP_FLAGS to use for allocations | |
6392 | * | |
6393 | * Return: 0 on success, -EINVAL on invalid request, -ENOMEM if memory could not | |
6394 | * be allocated. | |
6395 | */ | |
6396 | int mtree_store(struct maple_tree *mt, unsigned long index, void *entry, | |
6397 | gfp_t gfp) | |
6398 | { | |
6399 | return mtree_store_range(mt, index, index, entry, gfp); | |
6400 | } | |
6401 | EXPORT_SYMBOL(mtree_store); | |
6402 | ||
6403 | /** | |
4445e582 | 6404 | * mtree_insert_range() - Insert an entry at a given range if there is no value. |
54a611b6 LH |
6405 | * @mt: The maple tree |
6406 | * @first: The start of the range | |
6407 | * @last: The end of the range | |
6408 | * @entry: The entry to store | |
6409 | * @gfp: The GFP_FLAGS to use for allocations. | |
6410 | * | |
6411 | * Return: 0 on success, -EEXISTS if the range is occupied, -EINVAL on invalid | |
6412 | * request, -ENOMEM if memory could not be allocated. | |
6413 | */ | |
6414 | int mtree_insert_range(struct maple_tree *mt, unsigned long first, | |
6415 | unsigned long last, void *entry, gfp_t gfp) | |
6416 | { | |
6417 | MA_STATE(ms, mt, first, last); | |
6418 | ||
6419 | if (WARN_ON_ONCE(xa_is_advanced(entry))) | |
6420 | return -EINVAL; | |
6421 | ||
6422 | if (first > last) | |
6423 | return -EINVAL; | |
6424 | ||
6425 | mtree_lock(mt); | |
6426 | retry: | |
6427 | mas_insert(&ms, entry); | |
6428 | if (mas_nomem(&ms, gfp)) | |
6429 | goto retry; | |
6430 | ||
6431 | mtree_unlock(mt); | |
6432 | if (mas_is_err(&ms)) | |
6433 | return xa_err(ms.node); | |
6434 | ||
6435 | return 0; | |
6436 | } | |
6437 | EXPORT_SYMBOL(mtree_insert_range); | |
6438 | ||
6439 | /** | |
4445e582 | 6440 | * mtree_insert() - Insert an entry at a given index if there is no value. |
54a611b6 LH |
6441 | * @mt: The maple tree |
6442 | * @index : The index to store the value | |
6443 | * @entry: The entry to store | |
4ae6944d | 6444 | * @gfp: The GFP_FLAGS to use for allocations. |
54a611b6 LH |
6445 | * |
6446 | * Return: 0 on success, -EEXISTS if the range is occupied, -EINVAL on invalid | |
6447 | * request, -ENOMEM if memory could not be allocated. | |
6448 | */ | |
6449 | int mtree_insert(struct maple_tree *mt, unsigned long index, void *entry, | |
6450 | gfp_t gfp) | |
6451 | { | |
6452 | return mtree_insert_range(mt, index, index, entry, gfp); | |
6453 | } | |
6454 | EXPORT_SYMBOL(mtree_insert); | |
6455 | ||
6456 | int mtree_alloc_range(struct maple_tree *mt, unsigned long *startp, | |
6457 | void *entry, unsigned long size, unsigned long min, | |
6458 | unsigned long max, gfp_t gfp) | |
6459 | { | |
6460 | int ret = 0; | |
6461 | ||
52371677 | 6462 | MA_STATE(mas, mt, 0, 0); |
54a611b6 LH |
6463 | if (!mt_is_alloc(mt)) |
6464 | return -EINVAL; | |
6465 | ||
6466 | if (WARN_ON_ONCE(mt_is_reserved(entry))) | |
6467 | return -EINVAL; | |
6468 | ||
54a611b6 LH |
6469 | mtree_lock(mt); |
6470 | retry: | |
52371677 PZ |
6471 | ret = mas_empty_area(&mas, min, max, size); |
6472 | if (ret) | |
6473 | goto unlock; | |
6474 | ||
6475 | mas_insert(&mas, entry); | |
6476 | /* | |
6477 | * mas_nomem() may release the lock, causing the allocated area | |
6478 | * to be unavailable, so try to allocate a free area again. | |
6479 | */ | |
54a611b6 LH |
6480 | if (mas_nomem(&mas, gfp)) |
6481 | goto retry; | |
6482 | ||
52371677 PZ |
6483 | if (mas_is_err(&mas)) |
6484 | ret = xa_err(mas.node); | |
6485 | else | |
6486 | *startp = mas.index; | |
6487 | ||
6488 | unlock: | |
54a611b6 LH |
6489 | mtree_unlock(mt); |
6490 | return ret; | |
6491 | } | |
6492 | EXPORT_SYMBOL(mtree_alloc_range); | |
6493 | ||
9b6713cc CL |
6494 | /** |
6495 | * mtree_alloc_cyclic() - Find somewhere to store this entry in the tree. | |
6496 | * @mt: The maple tree. | |
6497 | * @startp: Pointer to ID. | |
6498 | * @range_lo: Lower bound of range to search. | |
6499 | * @range_hi: Upper bound of range to search. | |
6500 | * @entry: The entry to store. | |
6501 | * @next: Pointer to next ID to allocate. | |
6502 | * @gfp: The GFP_FLAGS to use for allocations. | |
6503 | * | |
6504 | * Finds an empty entry in @mt after @next, stores the new index into | |
6505 | * the @id pointer, stores the entry at that index, then updates @next. | |
6506 | * | |
6507 | * @mt must be initialized with the MT_FLAGS_ALLOC_RANGE flag. | |
6508 | * | |
6509 | * Context: Any context. Takes and releases the mt.lock. May sleep if | |
6510 | * the @gfp flags permit. | |
6511 | * | |
6512 | * Return: 0 if the allocation succeeded without wrapping, 1 if the | |
6513 | * allocation succeeded after wrapping, -ENOMEM if memory could not be | |
6514 | * allocated, -EINVAL if @mt cannot be used, or -EBUSY if there are no | |
6515 | * free entries. | |
6516 | */ | |
6517 | int mtree_alloc_cyclic(struct maple_tree *mt, unsigned long *startp, | |
6518 | void *entry, unsigned long range_lo, unsigned long range_hi, | |
6519 | unsigned long *next, gfp_t gfp) | |
6520 | { | |
6521 | int ret; | |
6522 | ||
6523 | MA_STATE(mas, mt, 0, 0); | |
6524 | ||
6525 | if (!mt_is_alloc(mt)) | |
6526 | return -EINVAL; | |
6527 | if (WARN_ON_ONCE(mt_is_reserved(entry))) | |
6528 | return -EINVAL; | |
6529 | mtree_lock(mt); | |
6530 | ret = mas_alloc_cyclic(&mas, startp, entry, range_lo, range_hi, | |
6531 | next, gfp); | |
6532 | mtree_unlock(mt); | |
6533 | return ret; | |
6534 | } | |
6535 | EXPORT_SYMBOL(mtree_alloc_cyclic); | |
6536 | ||
54a611b6 LH |
6537 | int mtree_alloc_rrange(struct maple_tree *mt, unsigned long *startp, |
6538 | void *entry, unsigned long size, unsigned long min, | |
6539 | unsigned long max, gfp_t gfp) | |
6540 | { | |
6541 | int ret = 0; | |
6542 | ||
52371677 | 6543 | MA_STATE(mas, mt, 0, 0); |
54a611b6 LH |
6544 | if (!mt_is_alloc(mt)) |
6545 | return -EINVAL; | |
6546 | ||
6547 | if (WARN_ON_ONCE(mt_is_reserved(entry))) | |
6548 | return -EINVAL; | |
6549 | ||
54a611b6 LH |
6550 | mtree_lock(mt); |
6551 | retry: | |
52371677 PZ |
6552 | ret = mas_empty_area_rev(&mas, min, max, size); |
6553 | if (ret) | |
6554 | goto unlock; | |
6555 | ||
6556 | mas_insert(&mas, entry); | |
6557 | /* | |
6558 | * mas_nomem() may release the lock, causing the allocated area | |
6559 | * to be unavailable, so try to allocate a free area again. | |
6560 | */ | |
54a611b6 LH |
6561 | if (mas_nomem(&mas, gfp)) |
6562 | goto retry; | |
6563 | ||
52371677 PZ |
6564 | if (mas_is_err(&mas)) |
6565 | ret = xa_err(mas.node); | |
6566 | else | |
6567 | *startp = mas.index; | |
6568 | ||
6569 | unlock: | |
54a611b6 LH |
6570 | mtree_unlock(mt); |
6571 | return ret; | |
6572 | } | |
6573 | EXPORT_SYMBOL(mtree_alloc_rrange); | |
6574 | ||
6575 | /** | |
6576 | * mtree_erase() - Find an index and erase the entire range. | |
6577 | * @mt: The maple tree | |
6578 | * @index: The index to erase | |
6579 | * | |
6580 | * Erasing is the same as a walk to an entry then a store of a NULL to that | |
6581 | * ENTIRE range. In fact, it is implemented as such using the advanced API. | |
6582 | * | |
6583 | * Return: The entry stored at the @index or %NULL | |
6584 | */ | |
6585 | void *mtree_erase(struct maple_tree *mt, unsigned long index) | |
6586 | { | |
6587 | void *entry = NULL; | |
6588 | ||
6589 | MA_STATE(mas, mt, index, index); | |
6590 | trace_ma_op(__func__, &mas); | |
6591 | ||
6592 | mtree_lock(mt); | |
6593 | entry = mas_erase(&mas); | |
6594 | mtree_unlock(mt); | |
6595 | ||
6596 | return entry; | |
6597 | } | |
6598 | EXPORT_SYMBOL(mtree_erase); | |
6599 | ||
fd32e4e9 PZ |
6600 | /* |
6601 | * mas_dup_free() - Free an incomplete duplication of a tree. | |
6602 | * @mas: The maple state of a incomplete tree. | |
6603 | * | |
6604 | * The parameter @mas->node passed in indicates that the allocation failed on | |
6605 | * this node. This function frees all nodes starting from @mas->node in the | |
6606 | * reverse order of mas_dup_build(). There is no need to hold the source tree | |
6607 | * lock at this time. | |
6608 | */ | |
6609 | static void mas_dup_free(struct ma_state *mas) | |
6610 | { | |
6611 | struct maple_node *node; | |
6612 | enum maple_type type; | |
6613 | void __rcu **slots; | |
6614 | unsigned char count, i; | |
6615 | ||
6616 | /* Maybe the first node allocation failed. */ | |
6617 | if (mas_is_none(mas)) | |
6618 | return; | |
6619 | ||
6620 | while (!mte_is_root(mas->node)) { | |
6621 | mas_ascend(mas); | |
6622 | if (mas->offset) { | |
6623 | mas->offset--; | |
6624 | do { | |
6625 | mas_descend(mas); | |
6626 | mas->offset = mas_data_end(mas); | |
6627 | } while (!mte_is_leaf(mas->node)); | |
6628 | ||
6629 | mas_ascend(mas); | |
6630 | } | |
6631 | ||
6632 | node = mte_to_node(mas->node); | |
6633 | type = mte_node_type(mas->node); | |
6634 | slots = ma_slots(node, type); | |
6635 | count = mas_data_end(mas) + 1; | |
6636 | for (i = 0; i < count; i++) | |
6637 | ((unsigned long *)slots)[i] &= ~MAPLE_NODE_MASK; | |
6638 | mt_free_bulk(count, slots); | |
6639 | } | |
6640 | ||
6641 | node = mte_to_node(mas->node); | |
6642 | mt_free_one(node); | |
6643 | } | |
6644 | ||
6645 | /* | |
6646 | * mas_copy_node() - Copy a maple node and replace the parent. | |
6647 | * @mas: The maple state of source tree. | |
6648 | * @new_mas: The maple state of new tree. | |
6649 | * @parent: The parent of the new node. | |
6650 | * | |
6651 | * Copy @mas->node to @new_mas->node, set @parent to be the parent of | |
6652 | * @new_mas->node. If memory allocation fails, @mas is set to -ENOMEM. | |
6653 | */ | |
6654 | static inline void mas_copy_node(struct ma_state *mas, struct ma_state *new_mas, | |
6655 | struct maple_pnode *parent) | |
6656 | { | |
6657 | struct maple_node *node = mte_to_node(mas->node); | |
6658 | struct maple_node *new_node = mte_to_node(new_mas->node); | |
6659 | unsigned long val; | |
6660 | ||
6661 | /* Copy the node completely. */ | |
6662 | memcpy(new_node, node, sizeof(struct maple_node)); | |
6663 | /* Update the parent node pointer. */ | |
6664 | val = (unsigned long)node->parent & MAPLE_NODE_MASK; | |
6665 | new_node->parent = ma_parent_ptr(val | (unsigned long)parent); | |
6666 | } | |
6667 | ||
6668 | /* | |
6669 | * mas_dup_alloc() - Allocate child nodes for a maple node. | |
6670 | * @mas: The maple state of source tree. | |
6671 | * @new_mas: The maple state of new tree. | |
6672 | * @gfp: The GFP_FLAGS to use for allocations. | |
6673 | * | |
6674 | * This function allocates child nodes for @new_mas->node during the duplication | |
6675 | * process. If memory allocation fails, @mas is set to -ENOMEM. | |
6676 | */ | |
6677 | static inline void mas_dup_alloc(struct ma_state *mas, struct ma_state *new_mas, | |
6678 | gfp_t gfp) | |
6679 | { | |
6680 | struct maple_node *node = mte_to_node(mas->node); | |
6681 | struct maple_node *new_node = mte_to_node(new_mas->node); | |
6682 | enum maple_type type; | |
6683 | unsigned char request, count, i; | |
6684 | void __rcu **slots; | |
6685 | void __rcu **new_slots; | |
6686 | unsigned long val; | |
6687 | ||
6688 | /* Allocate memory for child nodes. */ | |
6689 | type = mte_node_type(mas->node); | |
6690 | new_slots = ma_slots(new_node, type); | |
6691 | request = mas_data_end(mas) + 1; | |
6692 | count = mt_alloc_bulk(gfp, request, (void **)new_slots); | |
6693 | if (unlikely(count < request)) { | |
6694 | memset(new_slots, 0, request * sizeof(void *)); | |
6695 | mas_set_err(mas, -ENOMEM); | |
6696 | return; | |
6697 | } | |
6698 | ||
6699 | /* Restore node type information in slots. */ | |
6700 | slots = ma_slots(node, type); | |
6701 | for (i = 0; i < count; i++) { | |
6702 | val = (unsigned long)mt_slot_locked(mas->tree, slots, i); | |
6703 | val &= MAPLE_NODE_MASK; | |
6704 | ((unsigned long *)new_slots)[i] |= val; | |
6705 | } | |
6706 | } | |
6707 | ||
6708 | /* | |
6709 | * mas_dup_build() - Build a new maple tree from a source tree | |
6710 | * @mas: The maple state of source tree, need to be in MAS_START state. | |
6711 | * @new_mas: The maple state of new tree, need to be in MAS_START state. | |
6712 | * @gfp: The GFP_FLAGS to use for allocations. | |
6713 | * | |
6714 | * This function builds a new tree in DFS preorder. If the memory allocation | |
6715 | * fails, the error code -ENOMEM will be set in @mas, and @new_mas points to the | |
6716 | * last node. mas_dup_free() will free the incomplete duplication of a tree. | |
6717 | * | |
6718 | * Note that the attributes of the two trees need to be exactly the same, and the | |
6719 | * new tree needs to be empty, otherwise -EINVAL will be set in @mas. | |
6720 | */ | |
6721 | static inline void mas_dup_build(struct ma_state *mas, struct ma_state *new_mas, | |
6722 | gfp_t gfp) | |
6723 | { | |
6724 | struct maple_node *node; | |
6725 | struct maple_pnode *parent = NULL; | |
6726 | struct maple_enode *root; | |
6727 | enum maple_type type; | |
6728 | ||
6729 | if (unlikely(mt_attr(mas->tree) != mt_attr(new_mas->tree)) || | |
6730 | unlikely(!mtree_empty(new_mas->tree))) { | |
6731 | mas_set_err(mas, -EINVAL); | |
6732 | return; | |
6733 | } | |
6734 | ||
6735 | root = mas_start(mas); | |
6736 | if (mas_is_ptr(mas) || mas_is_none(mas)) | |
6737 | goto set_new_tree; | |
6738 | ||
6739 | node = mt_alloc_one(gfp); | |
6740 | if (!node) { | |
067311d3 | 6741 | new_mas->status = ma_none; |
fd32e4e9 PZ |
6742 | mas_set_err(mas, -ENOMEM); |
6743 | return; | |
6744 | } | |
6745 | ||
6746 | type = mte_node_type(mas->node); | |
6747 | root = mt_mk_node(node, type); | |
6748 | new_mas->node = root; | |
6749 | new_mas->min = 0; | |
6750 | new_mas->max = ULONG_MAX; | |
6751 | root = mte_mk_root(root); | |
6752 | while (1) { | |
6753 | mas_copy_node(mas, new_mas, parent); | |
6754 | if (!mte_is_leaf(mas->node)) { | |
6755 | /* Only allocate child nodes for non-leaf nodes. */ | |
6756 | mas_dup_alloc(mas, new_mas, gfp); | |
6757 | if (unlikely(mas_is_err(mas))) | |
6758 | return; | |
6759 | } else { | |
6760 | /* | |
6761 | * This is the last leaf node and duplication is | |
6762 | * completed. | |
6763 | */ | |
6764 | if (mas->max == ULONG_MAX) | |
6765 | goto done; | |
6766 | ||
6767 | /* This is not the last leaf node and needs to go up. */ | |
6768 | do { | |
6769 | mas_ascend(mas); | |
6770 | mas_ascend(new_mas); | |
6771 | } while (mas->offset == mas_data_end(mas)); | |
6772 | ||
6773 | /* Move to the next subtree. */ | |
6774 | mas->offset++; | |
6775 | new_mas->offset++; | |
6776 | } | |
6777 | ||
6778 | mas_descend(mas); | |
6779 | parent = ma_parent_ptr(mte_to_node(new_mas->node)); | |
6780 | mas_descend(new_mas); | |
6781 | mas->offset = 0; | |
6782 | new_mas->offset = 0; | |
6783 | } | |
6784 | done: | |
6785 | /* Specially handle the parent of the root node. */ | |
6786 | mte_to_node(root)->parent = ma_parent_ptr(mas_tree_parent(new_mas)); | |
6787 | set_new_tree: | |
6788 | /* Make them the same height */ | |
6789 | new_mas->tree->ma_flags = mas->tree->ma_flags; | |
6790 | rcu_assign_pointer(new_mas->tree->ma_root, root); | |
6791 | } | |
6792 | ||
6793 | /** | |
6794 | * __mt_dup(): Duplicate an entire maple tree | |
6795 | * @mt: The source maple tree | |
6796 | * @new: The new maple tree | |
6797 | * @gfp: The GFP_FLAGS to use for allocations | |
6798 | * | |
6799 | * This function duplicates a maple tree in Depth-First Search (DFS) pre-order | |
6800 | * traversal. It uses memcpy() to copy nodes in the source tree and allocate | |
6801 | * new child nodes in non-leaf nodes. The new node is exactly the same as the | |
6802 | * source node except for all the addresses stored in it. It will be faster than | |
6803 | * traversing all elements in the source tree and inserting them one by one into | |
6804 | * the new tree. | |
6805 | * The user needs to ensure that the attributes of the source tree and the new | |
6806 | * tree are the same, and the new tree needs to be an empty tree, otherwise | |
6807 | * -EINVAL will be returned. | |
6808 | * Note that the user needs to manually lock the source tree and the new tree. | |
6809 | * | |
6810 | * Return: 0 on success, -ENOMEM if memory could not be allocated, -EINVAL If | |
6811 | * the attributes of the two trees are different or the new tree is not an empty | |
6812 | * tree. | |
6813 | */ | |
6814 | int __mt_dup(struct maple_tree *mt, struct maple_tree *new, gfp_t gfp) | |
6815 | { | |
6816 | int ret = 0; | |
6817 | MA_STATE(mas, mt, 0, 0); | |
6818 | MA_STATE(new_mas, new, 0, 0); | |
6819 | ||
6820 | mas_dup_build(&mas, &new_mas, gfp); | |
6821 | if (unlikely(mas_is_err(&mas))) { | |
6822 | ret = xa_err(mas.node); | |
6823 | if (ret == -ENOMEM) | |
6824 | mas_dup_free(&new_mas); | |
6825 | } | |
6826 | ||
6827 | return ret; | |
6828 | } | |
6829 | EXPORT_SYMBOL(__mt_dup); | |
6830 | ||
6831 | /** | |
6832 | * mtree_dup(): Duplicate an entire maple tree | |
6833 | * @mt: The source maple tree | |
6834 | * @new: The new maple tree | |
6835 | * @gfp: The GFP_FLAGS to use for allocations | |
6836 | * | |
6837 | * This function duplicates a maple tree in Depth-First Search (DFS) pre-order | |
6838 | * traversal. It uses memcpy() to copy nodes in the source tree and allocate | |
6839 | * new child nodes in non-leaf nodes. The new node is exactly the same as the | |
6840 | * source node except for all the addresses stored in it. It will be faster than | |
6841 | * traversing all elements in the source tree and inserting them one by one into | |
6842 | * the new tree. | |
6843 | * The user needs to ensure that the attributes of the source tree and the new | |
6844 | * tree are the same, and the new tree needs to be an empty tree, otherwise | |
6845 | * -EINVAL will be returned. | |
6846 | * | |
6847 | * Return: 0 on success, -ENOMEM if memory could not be allocated, -EINVAL If | |
6848 | * the attributes of the two trees are different or the new tree is not an empty | |
6849 | * tree. | |
6850 | */ | |
6851 | int mtree_dup(struct maple_tree *mt, struct maple_tree *new, gfp_t gfp) | |
6852 | { | |
6853 | int ret = 0; | |
6854 | MA_STATE(mas, mt, 0, 0); | |
6855 | MA_STATE(new_mas, new, 0, 0); | |
6856 | ||
6857 | mas_lock(&new_mas); | |
6858 | mas_lock_nested(&mas, SINGLE_DEPTH_NESTING); | |
6859 | mas_dup_build(&mas, &new_mas, gfp); | |
6860 | mas_unlock(&mas); | |
6861 | if (unlikely(mas_is_err(&mas))) { | |
6862 | ret = xa_err(mas.node); | |
6863 | if (ret == -ENOMEM) | |
6864 | mas_dup_free(&new_mas); | |
6865 | } | |
6866 | ||
6867 | mas_unlock(&new_mas); | |
6868 | return ret; | |
6869 | } | |
6870 | EXPORT_SYMBOL(mtree_dup); | |
6871 | ||
54a611b6 LH |
6872 | /** |
6873 | * __mt_destroy() - Walk and free all nodes of a locked maple tree. | |
6874 | * @mt: The maple tree | |
6875 | * | |
6876 | * Note: Does not handle locking. | |
6877 | */ | |
6878 | void __mt_destroy(struct maple_tree *mt) | |
6879 | { | |
6880 | void *root = mt_root_locked(mt); | |
6881 | ||
6882 | rcu_assign_pointer(mt->ma_root, NULL); | |
6883 | if (xa_is_node(root)) | |
6884 | mte_destroy_walk(root, mt); | |
6885 | ||
8e50d32c | 6886 | mt->ma_flags = mt_attr(mt); |
54a611b6 LH |
6887 | } |
6888 | EXPORT_SYMBOL_GPL(__mt_destroy); | |
6889 | ||
6890 | /** | |
6891 | * mtree_destroy() - Destroy a maple tree | |
6892 | * @mt: The maple tree | |
6893 | * | |
6894 | * Frees all resources used by the tree. Handles locking. | |
6895 | */ | |
6896 | void mtree_destroy(struct maple_tree *mt) | |
6897 | { | |
6898 | mtree_lock(mt); | |
6899 | __mt_destroy(mt); | |
6900 | mtree_unlock(mt); | |
6901 | } | |
6902 | EXPORT_SYMBOL(mtree_destroy); | |
6903 | ||
6904 | /** | |
6905 | * mt_find() - Search from the start up until an entry is found. | |
6906 | * @mt: The maple tree | |
6907 | * @index: Pointer which contains the start location of the search | |
fad9c80e TG |
6908 | * @max: The maximum value of the search range |
6909 | * | |
6910 | * Takes RCU read lock internally to protect the search, which does not | |
6911 | * protect the returned pointer after dropping RCU read lock. | |
6912 | * See also: Documentation/core-api/maple_tree.rst | |
54a611b6 | 6913 | * |
fad9c80e TG |
6914 | * In case that an entry is found @index is updated to point to the next |
6915 | * possible entry independent whether the found entry is occupying a | |
6916 | * single index or a range if indices. | |
54a611b6 LH |
6917 | * |
6918 | * Return: The entry at or after the @index or %NULL | |
6919 | */ | |
6920 | void *mt_find(struct maple_tree *mt, unsigned long *index, unsigned long max) | |
6921 | { | |
6922 | MA_STATE(mas, mt, *index, *index); | |
6923 | void *entry; | |
6924 | #ifdef CONFIG_DEBUG_MAPLE_TREE | |
6925 | unsigned long copy = *index; | |
6926 | #endif | |
6927 | ||
6928 | trace_ma_read(__func__, &mas); | |
6929 | ||
6930 | if ((*index) > max) | |
6931 | return NULL; | |
6932 | ||
6933 | rcu_read_lock(); | |
6934 | retry: | |
6935 | entry = mas_state_walk(&mas); | |
6936 | if (mas_is_start(&mas)) | |
6937 | goto retry; | |
6938 | ||
6939 | if (unlikely(xa_is_zero(entry))) | |
6940 | entry = NULL; | |
6941 | ||
6942 | if (entry) | |
6943 | goto unlock; | |
6944 | ||
9a40d45c | 6945 | while (mas_is_active(&mas) && (mas.last < max)) { |
54a611b6 LH |
6946 | entry = mas_next_entry(&mas, max); |
6947 | if (likely(entry && !xa_is_zero(entry))) | |
6948 | break; | |
6949 | } | |
6950 | ||
6951 | if (unlikely(xa_is_zero(entry))) | |
6952 | entry = NULL; | |
6953 | unlock: | |
6954 | rcu_read_unlock(); | |
6955 | if (likely(entry)) { | |
6956 | *index = mas.last + 1; | |
6957 | #ifdef CONFIG_DEBUG_MAPLE_TREE | |
e6d6792a | 6958 | if (MT_WARN_ON(mt, (*index) && ((*index) <= copy))) |
54a611b6 LH |
6959 | pr_err("index not increased! %lx <= %lx\n", |
6960 | *index, copy); | |
54a611b6 LH |
6961 | #endif |
6962 | } | |
6963 | ||
6964 | return entry; | |
6965 | } | |
6966 | EXPORT_SYMBOL(mt_find); | |
6967 | ||
6968 | /** | |
6969 | * mt_find_after() - Search from the start up until an entry is found. | |
6970 | * @mt: The maple tree | |
6971 | * @index: Pointer which contains the start location of the search | |
6972 | * @max: The maximum value to check | |
6973 | * | |
fad9c80e TG |
6974 | * Same as mt_find() except that it checks @index for 0 before |
6975 | * searching. If @index == 0, the search is aborted. This covers a wrap | |
6976 | * around of @index to 0 in an iterator loop. | |
54a611b6 LH |
6977 | * |
6978 | * Return: The entry at or after the @index or %NULL | |
6979 | */ | |
6980 | void *mt_find_after(struct maple_tree *mt, unsigned long *index, | |
6981 | unsigned long max) | |
6982 | { | |
6983 | if (!(*index)) | |
6984 | return NULL; | |
6985 | ||
6986 | return mt_find(mt, index, max); | |
6987 | } | |
6988 | EXPORT_SYMBOL(mt_find_after); | |
6989 | ||
6990 | #ifdef CONFIG_DEBUG_MAPLE_TREE | |
6991 | atomic_t maple_tree_tests_run; | |
6992 | EXPORT_SYMBOL_GPL(maple_tree_tests_run); | |
6993 | atomic_t maple_tree_tests_passed; | |
6994 | EXPORT_SYMBOL_GPL(maple_tree_tests_passed); | |
6995 | ||
6996 | #ifndef __KERNEL__ | |
6997 | extern void kmem_cache_set_non_kernel(struct kmem_cache *, unsigned int); | |
6998 | void mt_set_non_kernel(unsigned int val) | |
6999 | { | |
7000 | kmem_cache_set_non_kernel(maple_node_cache, val); | |
7001 | } | |
7002 | ||
7003 | extern unsigned long kmem_cache_get_alloc(struct kmem_cache *); | |
7004 | unsigned long mt_get_alloc_size(void) | |
7005 | { | |
7006 | return kmem_cache_get_alloc(maple_node_cache); | |
7007 | } | |
7008 | ||
7009 | extern void kmem_cache_zero_nr_tallocated(struct kmem_cache *); | |
7010 | void mt_zero_nr_tallocated(void) | |
7011 | { | |
7012 | kmem_cache_zero_nr_tallocated(maple_node_cache); | |
7013 | } | |
7014 | ||
7015 | extern unsigned int kmem_cache_nr_tallocated(struct kmem_cache *); | |
7016 | unsigned int mt_nr_tallocated(void) | |
7017 | { | |
7018 | return kmem_cache_nr_tallocated(maple_node_cache); | |
7019 | } | |
7020 | ||
7021 | extern unsigned int kmem_cache_nr_allocated(struct kmem_cache *); | |
7022 | unsigned int mt_nr_allocated(void) | |
7023 | { | |
7024 | return kmem_cache_nr_allocated(maple_node_cache); | |
7025 | } | |
7026 | ||
120b1162 LH |
7027 | void mt_cache_shrink(void) |
7028 | { | |
7029 | } | |
7030 | #else | |
7031 | /* | |
7032 | * mt_cache_shrink() - For testing, don't use this. | |
7033 | * | |
7034 | * Certain testcases can trigger an OOM when combined with other memory | |
7035 | * debugging configuration options. This function is used to reduce the | |
7036 | * possibility of an out of memory even due to kmem_cache objects remaining | |
7037 | * around for longer than usual. | |
7038 | */ | |
7039 | void mt_cache_shrink(void) | |
7040 | { | |
7041 | kmem_cache_shrink(maple_node_cache); | |
7042 | ||
7043 | } | |
7044 | EXPORT_SYMBOL_GPL(mt_cache_shrink); | |
7045 | ||
7046 | #endif /* not defined __KERNEL__ */ | |
54a611b6 LH |
7047 | /* |
7048 | * mas_get_slot() - Get the entry in the maple state node stored at @offset. | |
7049 | * @mas: The maple state | |
7050 | * @offset: The offset into the slot array to fetch. | |
7051 | * | |
7052 | * Return: The entry stored at @offset. | |
7053 | */ | |
7054 | static inline struct maple_enode *mas_get_slot(struct ma_state *mas, | |
7055 | unsigned char offset) | |
7056 | { | |
7057 | return mas_slot(mas, ma_slots(mas_mn(mas), mte_node_type(mas->node)), | |
7058 | offset); | |
7059 | } | |
7060 | ||
54a611b6 LH |
7061 | /* Depth first search, post-order */ |
7062 | static void mas_dfs_postorder(struct ma_state *mas, unsigned long max) | |
7063 | { | |
7064 | ||
067311d3 | 7065 | struct maple_enode *p, *mn = mas->node; |
54a611b6 LH |
7066 | unsigned long p_min, p_max; |
7067 | ||
7068 | mas_next_node(mas, mas_mn(mas), max); | |
067311d3 | 7069 | if (!mas_is_overflow(mas)) |
54a611b6 LH |
7070 | return; |
7071 | ||
7072 | if (mte_is_root(mn)) | |
7073 | return; | |
7074 | ||
7075 | mas->node = mn; | |
7076 | mas_ascend(mas); | |
c3eb787e | 7077 | do { |
54a611b6 LH |
7078 | p = mas->node; |
7079 | p_min = mas->min; | |
7080 | p_max = mas->max; | |
7081 | mas_prev_node(mas, 0); | |
067311d3 | 7082 | } while (!mas_is_underflow(mas)); |
54a611b6 LH |
7083 | |
7084 | mas->node = p; | |
7085 | mas->max = p_max; | |
7086 | mas->min = p_min; | |
7087 | } | |
7088 | ||
7089 | /* Tree validations */ | |
7090 | static void mt_dump_node(const struct maple_tree *mt, void *entry, | |
89f499f3 LH |
7091 | unsigned long min, unsigned long max, unsigned int depth, |
7092 | enum mt_dump_format format); | |
54a611b6 | 7093 | static void mt_dump_range(unsigned long min, unsigned long max, |
89f499f3 | 7094 | unsigned int depth, enum mt_dump_format format) |
54a611b6 LH |
7095 | { |
7096 | static const char spaces[] = " "; | |
7097 | ||
89f499f3 LH |
7098 | switch(format) { |
7099 | case mt_dump_hex: | |
7100 | if (min == max) | |
7101 | pr_info("%.*s%lx: ", depth * 2, spaces, min); | |
7102 | else | |
7103 | pr_info("%.*s%lx-%lx: ", depth * 2, spaces, min, max); | |
7104 | break; | |
89f499f3 LH |
7105 | case mt_dump_dec: |
7106 | if (min == max) | |
7107 | pr_info("%.*s%lu: ", depth * 2, spaces, min); | |
7108 | else | |
7109 | pr_info("%.*s%lu-%lu: ", depth * 2, spaces, min, max); | |
7110 | } | |
54a611b6 LH |
7111 | } |
7112 | ||
7113 | static void mt_dump_entry(void *entry, unsigned long min, unsigned long max, | |
89f499f3 | 7114 | unsigned int depth, enum mt_dump_format format) |
54a611b6 | 7115 | { |
89f499f3 | 7116 | mt_dump_range(min, max, depth, format); |
54a611b6 LH |
7117 | |
7118 | if (xa_is_value(entry)) | |
7119 | pr_cont("value %ld (0x%lx) [%p]\n", xa_to_value(entry), | |
7120 | xa_to_value(entry), entry); | |
7121 | else if (xa_is_zero(entry)) | |
7122 | pr_cont("zero (%ld)\n", xa_to_internal(entry)); | |
7123 | else if (mt_is_reserved(entry)) | |
7124 | pr_cont("UNKNOWN ENTRY (%p)\n", entry); | |
7125 | else | |
7126 | pr_cont("%p\n", entry); | |
7127 | } | |
7128 | ||
7129 | static void mt_dump_range64(const struct maple_tree *mt, void *entry, | |
89f499f3 LH |
7130 | unsigned long min, unsigned long max, unsigned int depth, |
7131 | enum mt_dump_format format) | |
54a611b6 LH |
7132 | { |
7133 | struct maple_range_64 *node = &mte_to_node(entry)->mr64; | |
7134 | bool leaf = mte_is_leaf(entry); | |
7135 | unsigned long first = min; | |
7136 | int i; | |
7137 | ||
7138 | pr_cont(" contents: "); | |
89f499f3 LH |
7139 | for (i = 0; i < MAPLE_RANGE64_SLOTS - 1; i++) { |
7140 | switch(format) { | |
7141 | case mt_dump_hex: | |
7142 | pr_cont("%p %lX ", node->slot[i], node->pivot[i]); | |
7143 | break; | |
89f499f3 LH |
7144 | case mt_dump_dec: |
7145 | pr_cont("%p %lu ", node->slot[i], node->pivot[i]); | |
7146 | } | |
7147 | } | |
54a611b6 LH |
7148 | pr_cont("%p\n", node->slot[i]); |
7149 | for (i = 0; i < MAPLE_RANGE64_SLOTS; i++) { | |
7150 | unsigned long last = max; | |
7151 | ||
7152 | if (i < (MAPLE_RANGE64_SLOTS - 1)) | |
7153 | last = node->pivot[i]; | |
bd592703 | 7154 | else if (!node->slot[i] && max != mt_node_max(entry)) |
54a611b6 LH |
7155 | break; |
7156 | if (last == 0 && i > 0) | |
7157 | break; | |
7158 | if (leaf) | |
7159 | mt_dump_entry(mt_slot(mt, node->slot, i), | |
89f499f3 | 7160 | first, last, depth + 1, format); |
54a611b6 LH |
7161 | else if (node->slot[i]) |
7162 | mt_dump_node(mt, mt_slot(mt, node->slot, i), | |
89f499f3 | 7163 | first, last, depth + 1, format); |
54a611b6 LH |
7164 | |
7165 | if (last == max) | |
7166 | break; | |
7167 | if (last > max) { | |
89f499f3 LH |
7168 | switch(format) { |
7169 | case mt_dump_hex: | |
7170 | pr_err("node %p last (%lx) > max (%lx) at pivot %d!\n", | |
54a611b6 | 7171 | node, last, max, i); |
89f499f3 | 7172 | break; |
89f499f3 LH |
7173 | case mt_dump_dec: |
7174 | pr_err("node %p last (%lu) > max (%lu) at pivot %d!\n", | |
7175 | node, last, max, i); | |
7176 | } | |
54a611b6 LH |
7177 | } |
7178 | first = last + 1; | |
7179 | } | |
7180 | } | |
7181 | ||
7182 | static void mt_dump_arange64(const struct maple_tree *mt, void *entry, | |
89f499f3 LH |
7183 | unsigned long min, unsigned long max, unsigned int depth, |
7184 | enum mt_dump_format format) | |
54a611b6 LH |
7185 | { |
7186 | struct maple_arange_64 *node = &mte_to_node(entry)->ma64; | |
7187 | bool leaf = mte_is_leaf(entry); | |
7188 | unsigned long first = min; | |
7189 | int i; | |
7190 | ||
7191 | pr_cont(" contents: "); | |
83d97f62 LH |
7192 | for (i = 0; i < MAPLE_ARANGE64_SLOTS; i++) { |
7193 | switch (format) { | |
7194 | case mt_dump_hex: | |
7195 | pr_cont("%lx ", node->gap[i]); | |
7196 | break; | |
83d97f62 LH |
7197 | case mt_dump_dec: |
7198 | pr_cont("%lu ", node->gap[i]); | |
7199 | } | |
7200 | } | |
54a611b6 | 7201 | pr_cont("| %02X %02X| ", node->meta.end, node->meta.gap); |
83d97f62 LH |
7202 | for (i = 0; i < MAPLE_ARANGE64_SLOTS - 1; i++) { |
7203 | switch (format) { | |
7204 | case mt_dump_hex: | |
7205 | pr_cont("%p %lX ", node->slot[i], node->pivot[i]); | |
7206 | break; | |
83d97f62 LH |
7207 | case mt_dump_dec: |
7208 | pr_cont("%p %lu ", node->slot[i], node->pivot[i]); | |
7209 | } | |
7210 | } | |
54a611b6 LH |
7211 | pr_cont("%p\n", node->slot[i]); |
7212 | for (i = 0; i < MAPLE_ARANGE64_SLOTS; i++) { | |
7213 | unsigned long last = max; | |
7214 | ||
7215 | if (i < (MAPLE_ARANGE64_SLOTS - 1)) | |
7216 | last = node->pivot[i]; | |
7217 | else if (!node->slot[i]) | |
7218 | break; | |
7219 | if (last == 0 && i > 0) | |
7220 | break; | |
7221 | if (leaf) | |
7222 | mt_dump_entry(mt_slot(mt, node->slot, i), | |
89f499f3 | 7223 | first, last, depth + 1, format); |
54a611b6 LH |
7224 | else if (node->slot[i]) |
7225 | mt_dump_node(mt, mt_slot(mt, node->slot, i), | |
89f499f3 | 7226 | first, last, depth + 1, format); |
54a611b6 LH |
7227 | |
7228 | if (last == max) | |
7229 | break; | |
7230 | if (last > max) { | |
7231 | pr_err("node %p last (%lu) > max (%lu) at pivot %d!\n", | |
7232 | node, last, max, i); | |
7233 | break; | |
7234 | } | |
7235 | first = last + 1; | |
7236 | } | |
7237 | } | |
7238 | ||
7239 | static void mt_dump_node(const struct maple_tree *mt, void *entry, | |
89f499f3 LH |
7240 | unsigned long min, unsigned long max, unsigned int depth, |
7241 | enum mt_dump_format format) | |
54a611b6 LH |
7242 | { |
7243 | struct maple_node *node = mte_to_node(entry); | |
7244 | unsigned int type = mte_node_type(entry); | |
7245 | unsigned int i; | |
7246 | ||
89f499f3 | 7247 | mt_dump_range(min, max, depth, format); |
54a611b6 LH |
7248 | |
7249 | pr_cont("node %p depth %d type %d parent %p", node, depth, type, | |
7250 | node ? node->parent : NULL); | |
7251 | switch (type) { | |
7252 | case maple_dense: | |
7253 | pr_cont("\n"); | |
7254 | for (i = 0; i < MAPLE_NODE_SLOTS; i++) { | |
7255 | if (min + i > max) | |
7256 | pr_cont("OUT OF RANGE: "); | |
7257 | mt_dump_entry(mt_slot(mt, node->slot, i), | |
89f499f3 | 7258 | min + i, min + i, depth, format); |
54a611b6 LH |
7259 | } |
7260 | break; | |
7261 | case maple_leaf_64: | |
7262 | case maple_range_64: | |
89f499f3 | 7263 | mt_dump_range64(mt, entry, min, max, depth, format); |
54a611b6 LH |
7264 | break; |
7265 | case maple_arange_64: | |
89f499f3 | 7266 | mt_dump_arange64(mt, entry, min, max, depth, format); |
54a611b6 LH |
7267 | break; |
7268 | ||
7269 | default: | |
7270 | pr_cont(" UNKNOWN TYPE\n"); | |
7271 | } | |
7272 | } | |
7273 | ||
89f499f3 | 7274 | void mt_dump(const struct maple_tree *mt, enum mt_dump_format format) |
54a611b6 LH |
7275 | { |
7276 | void *entry = rcu_dereference_check(mt->ma_root, mt_locked(mt)); | |
7277 | ||
7278 | pr_info("maple_tree(%p) flags %X, height %u root %p\n", | |
7279 | mt, mt->ma_flags, mt_height(mt), entry); | |
7280 | if (!xa_is_node(entry)) | |
89f499f3 | 7281 | mt_dump_entry(entry, 0, 0, 0, format); |
54a611b6 | 7282 | else if (entry) |
89f499f3 | 7283 | mt_dump_node(mt, entry, 0, mt_node_max(entry), 0, format); |
54a611b6 | 7284 | } |
120b1162 | 7285 | EXPORT_SYMBOL_GPL(mt_dump); |
54a611b6 LH |
7286 | |
7287 | /* | |
7288 | * Calculate the maximum gap in a node and check if that's what is reported in | |
7289 | * the parent (unless root). | |
7290 | */ | |
7291 | static void mas_validate_gaps(struct ma_state *mas) | |
7292 | { | |
7293 | struct maple_enode *mte = mas->node; | |
f8e5eac8 PZ |
7294 | struct maple_node *p_mn, *node = mte_to_node(mte); |
7295 | enum maple_type mt = mte_node_type(mas->node); | |
54a611b6 LH |
7296 | unsigned long gap = 0, max_gap = 0; |
7297 | unsigned long p_end, p_start = mas->min; | |
f8e5eac8 | 7298 | unsigned char p_slot, offset; |
54a611b6 | 7299 | unsigned long *gaps = NULL; |
f8e5eac8 PZ |
7300 | unsigned long *pivots = ma_pivots(node, mt); |
7301 | unsigned int i; | |
54a611b6 | 7302 | |
f8e5eac8 | 7303 | if (ma_is_dense(mt)) { |
54a611b6 LH |
7304 | for (i = 0; i < mt_slot_count(mte); i++) { |
7305 | if (mas_get_slot(mas, i)) { | |
7306 | if (gap > max_gap) | |
7307 | max_gap = gap; | |
7308 | gap = 0; | |
7309 | continue; | |
7310 | } | |
7311 | gap++; | |
7312 | } | |
7313 | goto counted; | |
7314 | } | |
7315 | ||
f8e5eac8 | 7316 | gaps = ma_gaps(node, mt); |
54a611b6 | 7317 | for (i = 0; i < mt_slot_count(mte); i++) { |
29b2681f | 7318 | p_end = mas_safe_pivot(mas, pivots, i, mt); |
54a611b6 LH |
7319 | |
7320 | if (!gaps) { | |
f8e5eac8 PZ |
7321 | if (!mas_get_slot(mas, i)) |
7322 | gap = p_end - p_start + 1; | |
54a611b6 LH |
7323 | } else { |
7324 | void *entry = mas_get_slot(mas, i); | |
7325 | ||
7326 | gap = gaps[i]; | |
f8e5eac8 PZ |
7327 | MT_BUG_ON(mas->tree, !entry); |
7328 | ||
7329 | if (gap > p_end - p_start + 1) { | |
7330 | pr_err("%p[%u] %lu >= %lu - %lu + 1 (%lu)\n", | |
7331 | mas_mn(mas), i, gap, p_end, p_start, | |
7332 | p_end - p_start + 1); | |
7333 | MT_BUG_ON(mas->tree, gap > p_end - p_start + 1); | |
54a611b6 LH |
7334 | } |
7335 | } | |
7336 | ||
7337 | if (gap > max_gap) | |
7338 | max_gap = gap; | |
f8e5eac8 | 7339 | |
54a611b6 LH |
7340 | p_start = p_end + 1; |
7341 | if (p_end >= mas->max) | |
7342 | break; | |
7343 | } | |
7344 | ||
7345 | counted: | |
f8e5eac8 | 7346 | if (mt == maple_arange_64) { |
2e783f0c | 7347 | MT_BUG_ON(mas->tree, !gaps); |
c5e94121 | 7348 | offset = ma_meta_gap(node); |
f8e5eac8 PZ |
7349 | if (offset > i) { |
7350 | pr_err("gap offset %p[%u] is invalid\n", node, offset); | |
7351 | MT_BUG_ON(mas->tree, 1); | |
7352 | } | |
7353 | ||
7354 | if (gaps[offset] != max_gap) { | |
7355 | pr_err("gap %p[%u] is not the largest gap %lu\n", | |
7356 | node, offset, max_gap); | |
7357 | MT_BUG_ON(mas->tree, 1); | |
7358 | } | |
7359 | ||
f8e5eac8 PZ |
7360 | for (i++ ; i < mt_slot_count(mte); i++) { |
7361 | if (gaps[i] != 0) { | |
7362 | pr_err("gap %p[%u] beyond node limit != 0\n", | |
7363 | node, i); | |
7364 | MT_BUG_ON(mas->tree, 1); | |
7365 | } | |
7366 | } | |
7367 | } | |
7368 | ||
54a611b6 LH |
7369 | if (mte_is_root(mte)) |
7370 | return; | |
7371 | ||
7372 | p_slot = mte_parent_slot(mas->node); | |
7373 | p_mn = mte_parent(mte); | |
7374 | MT_BUG_ON(mas->tree, max_gap > mas->max); | |
afc754c6 | 7375 | if (ma_gaps(p_mn, mas_parent_type(mas, mte))[p_slot] != max_gap) { |
54a611b6 | 7376 | pr_err("gap %p[%u] != %lu\n", p_mn, p_slot, max_gap); |
89f499f3 | 7377 | mt_dump(mas->tree, mt_dump_hex); |
f8e5eac8 | 7378 | MT_BUG_ON(mas->tree, 1); |
54a611b6 | 7379 | } |
54a611b6 LH |
7380 | } |
7381 | ||
7382 | static void mas_validate_parent_slot(struct ma_state *mas) | |
7383 | { | |
7384 | struct maple_node *parent; | |
7385 | struct maple_enode *node; | |
afc754c6 LH |
7386 | enum maple_type p_type; |
7387 | unsigned char p_slot; | |
54a611b6 LH |
7388 | void __rcu **slots; |
7389 | int i; | |
7390 | ||
7391 | if (mte_is_root(mas->node)) | |
7392 | return; | |
7393 | ||
afc754c6 LH |
7394 | p_slot = mte_parent_slot(mas->node); |
7395 | p_type = mas_parent_type(mas, mas->node); | |
54a611b6 LH |
7396 | parent = mte_parent(mas->node); |
7397 | slots = ma_slots(parent, p_type); | |
7398 | MT_BUG_ON(mas->tree, mas_mn(mas) == parent); | |
7399 | ||
7400 | /* Check prev/next parent slot for duplicate node entry */ | |
7401 | ||
7402 | for (i = 0; i < mt_slots[p_type]; i++) { | |
7403 | node = mas_slot(mas, slots, i); | |
7404 | if (i == p_slot) { | |
7405 | if (node != mas->node) | |
7406 | pr_err("parent %p[%u] does not have %p\n", | |
7407 | parent, i, mas_mn(mas)); | |
7408 | MT_BUG_ON(mas->tree, node != mas->node); | |
7409 | } else if (node == mas->node) { | |
7410 | pr_err("Invalid child %p at parent %p[%u] p_slot %u\n", | |
7411 | mas_mn(mas), parent, i, p_slot); | |
7412 | MT_BUG_ON(mas->tree, node == mas->node); | |
7413 | } | |
7414 | } | |
7415 | } | |
7416 | ||
7417 | static void mas_validate_child_slot(struct ma_state *mas) | |
7418 | { | |
7419 | enum maple_type type = mte_node_type(mas->node); | |
7420 | void __rcu **slots = ma_slots(mte_to_node(mas->node), type); | |
7421 | unsigned long *pivots = ma_pivots(mte_to_node(mas->node), type); | |
7422 | struct maple_enode *child; | |
7423 | unsigned char i; | |
7424 | ||
7425 | if (mte_is_leaf(mas->node)) | |
7426 | return; | |
7427 | ||
7428 | for (i = 0; i < mt_slots[type]; i++) { | |
7429 | child = mas_slot(mas, slots, i); | |
54a611b6 | 7430 | |
e93fda5a PZ |
7431 | if (!child) { |
7432 | pr_err("Non-leaf node lacks child at %p[%u]\n", | |
7433 | mas_mn(mas), i); | |
7434 | MT_BUG_ON(mas->tree, 1); | |
7435 | } | |
54a611b6 LH |
7436 | |
7437 | if (mte_parent_slot(child) != i) { | |
7438 | pr_err("Slot error at %p[%u]: child %p has pslot %u\n", | |
7439 | mas_mn(mas), i, mte_to_node(child), | |
7440 | mte_parent_slot(child)); | |
7441 | MT_BUG_ON(mas->tree, 1); | |
7442 | } | |
7443 | ||
7444 | if (mte_parent(child) != mte_to_node(mas->node)) { | |
7445 | pr_err("child %p has parent %p not %p\n", | |
7446 | mte_to_node(child), mte_parent(child), | |
7447 | mte_to_node(mas->node)); | |
7448 | MT_BUG_ON(mas->tree, 1); | |
7449 | } | |
e93fda5a PZ |
7450 | |
7451 | if (i < mt_pivots[type] && pivots[i] == mas->max) | |
7452 | break; | |
54a611b6 LH |
7453 | } |
7454 | } | |
7455 | ||
7456 | /* | |
33af39d0 PZ |
7457 | * Validate all pivots are within mas->min and mas->max, check metadata ends |
7458 | * where the maximum ends and ensure there is no slots or pivots set outside of | |
7459 | * the end of the data. | |
54a611b6 LH |
7460 | */ |
7461 | static void mas_validate_limits(struct ma_state *mas) | |
7462 | { | |
7463 | int i; | |
7464 | unsigned long prev_piv = 0; | |
7465 | enum maple_type type = mte_node_type(mas->node); | |
7466 | void __rcu **slots = ma_slots(mte_to_node(mas->node), type); | |
7467 | unsigned long *pivots = ma_pivots(mas_mn(mas), type); | |
7468 | ||
54a611b6 LH |
7469 | for (i = 0; i < mt_slots[type]; i++) { |
7470 | unsigned long piv; | |
7471 | ||
7472 | piv = mas_safe_pivot(mas, pivots, i, type); | |
7473 | ||
33af39d0 PZ |
7474 | if (!piv && (i != 0)) { |
7475 | pr_err("Missing node limit pivot at %p[%u]", | |
7476 | mas_mn(mas), i); | |
7477 | MAS_WARN_ON(mas, 1); | |
54a611b6 LH |
7478 | } |
7479 | ||
7480 | if (prev_piv > piv) { | |
7481 | pr_err("%p[%u] piv %lu < prev_piv %lu\n", | |
7482 | mas_mn(mas), i, piv, prev_piv); | |
e6d6792a | 7483 | MAS_WARN_ON(mas, piv < prev_piv); |
54a611b6 LH |
7484 | } |
7485 | ||
7486 | if (piv < mas->min) { | |
7487 | pr_err("%p[%u] %lu < %lu\n", mas_mn(mas), i, | |
7488 | piv, mas->min); | |
e6d6792a | 7489 | MAS_WARN_ON(mas, piv < mas->min); |
54a611b6 LH |
7490 | } |
7491 | if (piv > mas->max) { | |
7492 | pr_err("%p[%u] %lu > %lu\n", mas_mn(mas), i, | |
7493 | piv, mas->max); | |
e6d6792a | 7494 | MAS_WARN_ON(mas, piv > mas->max); |
54a611b6 LH |
7495 | } |
7496 | prev_piv = piv; | |
7497 | if (piv == mas->max) | |
7498 | break; | |
7499 | } | |
33af39d0 PZ |
7500 | |
7501 | if (mas_data_end(mas) != i) { | |
7502 | pr_err("node%p: data_end %u != the last slot offset %u\n", | |
7503 | mas_mn(mas), mas_data_end(mas), i); | |
7504 | MT_BUG_ON(mas->tree, 1); | |
7505 | } | |
7506 | ||
54a611b6 LH |
7507 | for (i += 1; i < mt_slots[type]; i++) { |
7508 | void *entry = mas_slot(mas, slots, i); | |
7509 | ||
7510 | if (entry && (i != mt_slots[type] - 1)) { | |
7511 | pr_err("%p[%u] should not have entry %p\n", mas_mn(mas), | |
7512 | i, entry); | |
7513 | MT_BUG_ON(mas->tree, entry != NULL); | |
7514 | } | |
7515 | ||
7516 | if (i < mt_pivots[type]) { | |
7517 | unsigned long piv = pivots[i]; | |
7518 | ||
7519 | if (!piv) | |
7520 | continue; | |
7521 | ||
7522 | pr_err("%p[%u] should not have piv %lu\n", | |
7523 | mas_mn(mas), i, piv); | |
e6d6792a | 7524 | MAS_WARN_ON(mas, i < mt_pivots[type] - 1); |
54a611b6 LH |
7525 | } |
7526 | } | |
7527 | } | |
7528 | ||
7529 | static void mt_validate_nulls(struct maple_tree *mt) | |
7530 | { | |
7531 | void *entry, *last = (void *)1; | |
7532 | unsigned char offset = 0; | |
7533 | void __rcu **slots; | |
7534 | MA_STATE(mas, mt, 0, 0); | |
7535 | ||
7536 | mas_start(&mas); | |
067311d3 | 7537 | if (mas_is_none(&mas) || (mas_is_ptr(&mas))) |
54a611b6 LH |
7538 | return; |
7539 | ||
7540 | while (!mte_is_leaf(mas.node)) | |
7541 | mas_descend(&mas); | |
7542 | ||
7543 | slots = ma_slots(mte_to_node(mas.node), mte_node_type(mas.node)); | |
7544 | do { | |
7545 | entry = mas_slot(&mas, slots, offset); | |
7546 | if (!last && !entry) { | |
7547 | pr_err("Sequential nulls end at %p[%u]\n", | |
7548 | mas_mn(&mas), offset); | |
7549 | } | |
7550 | MT_BUG_ON(mt, !last && !entry); | |
7551 | last = entry; | |
7552 | if (offset == mas_data_end(&mas)) { | |
7553 | mas_next_node(&mas, mas_mn(&mas), ULONG_MAX); | |
067311d3 | 7554 | if (mas_is_overflow(&mas)) |
54a611b6 LH |
7555 | return; |
7556 | offset = 0; | |
7557 | slots = ma_slots(mte_to_node(mas.node), | |
7558 | mte_node_type(mas.node)); | |
7559 | } else { | |
7560 | offset++; | |
7561 | } | |
7562 | ||
067311d3 | 7563 | } while (!mas_is_overflow(&mas)); |
54a611b6 LH |
7564 | } |
7565 | ||
7566 | /* | |
7567 | * validate a maple tree by checking: | |
7568 | * 1. The limits (pivots are within mas->min to mas->max) | |
7569 | * 2. The gap is correctly set in the parents | |
7570 | */ | |
7571 | void mt_validate(struct maple_tree *mt) | |
7572 | { | |
7573 | unsigned char end; | |
7574 | ||
7575 | MA_STATE(mas, mt, 0, 0); | |
7576 | rcu_read_lock(); | |
7577 | mas_start(&mas); | |
9a40d45c | 7578 | if (!mas_is_active(&mas)) |
54a611b6 LH |
7579 | goto done; |
7580 | ||
a489539e PZ |
7581 | while (!mte_is_leaf(mas.node)) |
7582 | mas_descend(&mas); | |
7583 | ||
067311d3 | 7584 | while (!mas_is_overflow(&mas)) { |
e6d6792a | 7585 | MAS_WARN_ON(&mas, mte_dead_node(mas.node)); |
a489539e PZ |
7586 | end = mas_data_end(&mas); |
7587 | if (MAS_WARN_ON(&mas, (end < mt_min_slot_count(mas.node)) && | |
7588 | (mas.max != ULONG_MAX))) { | |
7589 | pr_err("Invalid size %u of %p\n", end, mas_mn(&mas)); | |
54a611b6 | 7590 | } |
a489539e | 7591 | |
54a611b6 | 7592 | mas_validate_parent_slot(&mas); |
54a611b6 | 7593 | mas_validate_limits(&mas); |
a489539e | 7594 | mas_validate_child_slot(&mas); |
54a611b6 LH |
7595 | if (mt_is_alloc(mt)) |
7596 | mas_validate_gaps(&mas); | |
7597 | mas_dfs_postorder(&mas, ULONG_MAX); | |
7598 | } | |
7599 | mt_validate_nulls(mt); | |
7600 | done: | |
7601 | rcu_read_unlock(); | |
7602 | ||
7603 | } | |
120b1162 | 7604 | EXPORT_SYMBOL_GPL(mt_validate); |
54a611b6 | 7605 | |
f0a1f866 LH |
7606 | void mas_dump(const struct ma_state *mas) |
7607 | { | |
7608 | pr_err("MAS: tree=%p enode=%p ", mas->tree, mas->node); | |
067311d3 LH |
7609 | switch (mas->status) { |
7610 | case ma_active: | |
7611 | pr_err("(ma_active)"); | |
7612 | break; | |
7613 | case ma_none: | |
7614 | pr_err("(ma_none)"); | |
7615 | break; | |
7616 | case ma_root: | |
7617 | pr_err("(ma_root)"); | |
7618 | break; | |
7619 | case ma_start: | |
7620 | pr_err("(ma_start) "); | |
7621 | break; | |
7622 | case ma_pause: | |
7623 | pr_err("(ma_pause) "); | |
7624 | break; | |
7625 | case ma_overflow: | |
7626 | pr_err("(ma_overflow) "); | |
7627 | break; | |
7628 | case ma_underflow: | |
7629 | pr_err("(ma_underflow) "); | |
7630 | break; | |
7631 | case ma_error: | |
7632 | pr_err("(ma_error) "); | |
7633 | break; | |
7634 | } | |
7635 | ||
7636 | pr_err("[%u/%u] index=%lx last=%lx\n", mas->offset, mas->end, | |
7637 | mas->index, mas->last); | |
f0a1f866 LH |
7638 | pr_err(" min=%lx max=%lx alloc=%p, depth=%u, flags=%x\n", |
7639 | mas->min, mas->max, mas->alloc, mas->depth, mas->mas_flags); | |
7640 | if (mas->index > mas->last) | |
7641 | pr_err("Check index & last\n"); | |
7642 | } | |
7643 | EXPORT_SYMBOL_GPL(mas_dump); | |
7644 | ||
7645 | void mas_wr_dump(const struct ma_wr_state *wr_mas) | |
7646 | { | |
7647 | pr_err("WR_MAS: node=%p r_min=%lx r_max=%lx\n", | |
7648 | wr_mas->node, wr_mas->r_min, wr_mas->r_max); | |
7649 | pr_err(" type=%u off_end=%u, node_end=%u, end_piv=%lx\n", | |
0de56e38 | 7650 | wr_mas->type, wr_mas->offset_end, wr_mas->mas->end, |
f0a1f866 LH |
7651 | wr_mas->end_piv); |
7652 | } | |
7653 | EXPORT_SYMBOL_GPL(mas_wr_dump); | |
7654 | ||
54a611b6 | 7655 | #endif /* CONFIG_DEBUG_MAPLE_TREE */ |