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54a611b6 LH |
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> | |
7 | */ | |
8 | ||
9 | /* | |
10 | * DOC: Interesting implementation details of the Maple Tree | |
11 | * | |
12 | * Each node type has a number of slots for entries and a number of slots for | |
13 | * pivots. In the case of dense nodes, the pivots are implied by the position | |
14 | * and are simply the slot index + the minimum of the node. | |
15 | * | |
16 | * In regular B-Tree terms, pivots are called keys. The term pivot is used to | |
17 | * indicate that the tree is specifying ranges, Pivots may appear in the | |
18 | * subtree with an entry attached to the value where as keys are unique to a | |
19 | * specific position of a B-tree. Pivot values are inclusive of the slot with | |
20 | * the same index. | |
21 | * | |
22 | * | |
23 | * The following illustrates the layout of a range64 nodes slots and pivots. | |
24 | * | |
25 | * | |
26 | * Slots -> | 0 | 1 | 2 | ... | 12 | 13 | 14 | 15 | | |
27 | * ┬ ┬ ┬ ┬ ┬ ┬ ┬ ┬ ┬ | |
28 | * │ │ │ │ │ │ │ │ └─ Implied maximum | |
29 | * │ │ │ │ │ │ │ └─ Pivot 14 | |
30 | * │ │ │ │ │ │ └─ Pivot 13 | |
31 | * │ │ │ │ │ └─ Pivot 12 | |
32 | * │ │ │ │ └─ Pivot 11 | |
33 | * │ │ │ └─ Pivot 2 | |
34 | * │ │ └─ Pivot 1 | |
35 | * │ └─ Pivot 0 | |
36 | * └─ Implied minimum | |
37 | * | |
38 | * Slot contents: | |
39 | * Internal (non-leaf) nodes contain pointers to other nodes. | |
40 | * Leaf nodes contain entries. | |
41 | * | |
42 | * The location of interest is often referred to as an offset. All offsets have | |
43 | * a slot, but the last offset has an implied pivot from the node above (or | |
44 | * UINT_MAX for the root node. | |
45 | * | |
46 | * Ranges complicate certain write activities. When modifying any of | |
47 | * the B-tree variants, it is known that one entry will either be added or | |
48 | * deleted. When modifying the Maple Tree, one store operation may overwrite | |
49 | * the entire data set, or one half of the tree, or the middle half of the tree. | |
50 | * | |
51 | */ | |
52 | ||
53 | ||
54 | #include <linux/maple_tree.h> | |
55 | #include <linux/xarray.h> | |
56 | #include <linux/types.h> | |
57 | #include <linux/export.h> | |
58 | #include <linux/slab.h> | |
59 | #include <linux/limits.h> | |
60 | #include <asm/barrier.h> | |
61 | ||
62 | #define CREATE_TRACE_POINTS | |
63 | #include <trace/events/maple_tree.h> | |
64 | ||
65 | #define MA_ROOT_PARENT 1 | |
66 | ||
67 | /* | |
68 | * Maple state flags | |
69 | * * MA_STATE_BULK - Bulk insert mode | |
70 | * * MA_STATE_REBALANCE - Indicate a rebalance during bulk insert | |
71 | * * MA_STATE_PREALLOC - Preallocated nodes, WARN_ON allocation | |
72 | */ | |
73 | #define MA_STATE_BULK 1 | |
74 | #define MA_STATE_REBALANCE 2 | |
75 | #define MA_STATE_PREALLOC 4 | |
76 | ||
77 | #define ma_parent_ptr(x) ((struct maple_pnode *)(x)) | |
4ffc2ee2 | 78 | #define mas_tree_parent(x) ((unsigned long)(x->tree) | MA_ROOT_PARENT) |
54a611b6 LH |
79 | #define ma_mnode_ptr(x) ((struct maple_node *)(x)) |
80 | #define ma_enode_ptr(x) ((struct maple_enode *)(x)) | |
81 | static struct kmem_cache *maple_node_cache; | |
82 | ||
83 | #ifdef CONFIG_DEBUG_MAPLE_TREE | |
84 | static const unsigned long mt_max[] = { | |
85 | [maple_dense] = MAPLE_NODE_SLOTS, | |
86 | [maple_leaf_64] = ULONG_MAX, | |
87 | [maple_range_64] = ULONG_MAX, | |
88 | [maple_arange_64] = ULONG_MAX, | |
89 | }; | |
90 | #define mt_node_max(x) mt_max[mte_node_type(x)] | |
91 | #endif | |
92 | ||
93 | static const unsigned char mt_slots[] = { | |
94 | [maple_dense] = MAPLE_NODE_SLOTS, | |
95 | [maple_leaf_64] = MAPLE_RANGE64_SLOTS, | |
96 | [maple_range_64] = MAPLE_RANGE64_SLOTS, | |
97 | [maple_arange_64] = MAPLE_ARANGE64_SLOTS, | |
98 | }; | |
99 | #define mt_slot_count(x) mt_slots[mte_node_type(x)] | |
100 | ||
101 | static const unsigned char mt_pivots[] = { | |
102 | [maple_dense] = 0, | |
103 | [maple_leaf_64] = MAPLE_RANGE64_SLOTS - 1, | |
104 | [maple_range_64] = MAPLE_RANGE64_SLOTS - 1, | |
105 | [maple_arange_64] = MAPLE_ARANGE64_SLOTS - 1, | |
106 | }; | |
107 | #define mt_pivot_count(x) mt_pivots[mte_node_type(x)] | |
108 | ||
109 | static const unsigned char mt_min_slots[] = { | |
110 | [maple_dense] = MAPLE_NODE_SLOTS / 2, | |
111 | [maple_leaf_64] = (MAPLE_RANGE64_SLOTS / 2) - 2, | |
112 | [maple_range_64] = (MAPLE_RANGE64_SLOTS / 2) - 2, | |
113 | [maple_arange_64] = (MAPLE_ARANGE64_SLOTS / 2) - 1, | |
114 | }; | |
115 | #define mt_min_slot_count(x) mt_min_slots[mte_node_type(x)] | |
116 | ||
117 | #define MAPLE_BIG_NODE_SLOTS (MAPLE_RANGE64_SLOTS * 2 + 2) | |
118 | #define MAPLE_BIG_NODE_GAPS (MAPLE_ARANGE64_SLOTS * 2 + 1) | |
119 | ||
120 | struct maple_big_node { | |
121 | struct maple_pnode *parent; | |
122 | unsigned long pivot[MAPLE_BIG_NODE_SLOTS - 1]; | |
123 | union { | |
124 | struct maple_enode *slot[MAPLE_BIG_NODE_SLOTS]; | |
125 | struct { | |
126 | unsigned long padding[MAPLE_BIG_NODE_GAPS]; | |
127 | unsigned long gap[MAPLE_BIG_NODE_GAPS]; | |
128 | }; | |
129 | }; | |
130 | unsigned char b_end; | |
131 | enum maple_type type; | |
132 | }; | |
133 | ||
134 | /* | |
135 | * The maple_subtree_state is used to build a tree to replace a segment of an | |
136 | * existing tree in a more atomic way. Any walkers of the older tree will hit a | |
137 | * dead node and restart on updates. | |
138 | */ | |
139 | struct maple_subtree_state { | |
140 | struct ma_state *orig_l; /* Original left side of subtree */ | |
141 | struct ma_state *orig_r; /* Original right side of subtree */ | |
142 | struct ma_state *l; /* New left side of subtree */ | |
143 | struct ma_state *m; /* New middle of subtree (rare) */ | |
144 | struct ma_state *r; /* New right side of subtree */ | |
145 | struct ma_topiary *free; /* nodes to be freed */ | |
146 | struct ma_topiary *destroy; /* Nodes to be destroyed (walked and freed) */ | |
147 | struct maple_big_node *bn; | |
148 | }; | |
149 | ||
44081c77 AB |
150 | #ifdef CONFIG_KASAN_STACK |
151 | /* Prevent mas_wr_bnode() from exceeding the stack frame limit */ | |
152 | #define noinline_for_kasan noinline_for_stack | |
153 | #else | |
154 | #define noinline_for_kasan inline | |
155 | #endif | |
156 | ||
54a611b6 LH |
157 | /* Functions */ |
158 | static inline struct maple_node *mt_alloc_one(gfp_t gfp) | |
159 | { | |
541e06b7 | 160 | return kmem_cache_alloc(maple_node_cache, gfp); |
54a611b6 LH |
161 | } |
162 | ||
163 | static inline int mt_alloc_bulk(gfp_t gfp, size_t size, void **nodes) | |
164 | { | |
541e06b7 | 165 | return kmem_cache_alloc_bulk(maple_node_cache, gfp, size, nodes); |
54a611b6 LH |
166 | } |
167 | ||
168 | static inline void mt_free_bulk(size_t size, void __rcu **nodes) | |
169 | { | |
170 | kmem_cache_free_bulk(maple_node_cache, size, (void **)nodes); | |
171 | } | |
172 | ||
173 | static void mt_free_rcu(struct rcu_head *head) | |
174 | { | |
175 | struct maple_node *node = container_of(head, struct maple_node, rcu); | |
176 | ||
177 | kmem_cache_free(maple_node_cache, node); | |
178 | } | |
179 | ||
180 | /* | |
181 | * ma_free_rcu() - Use rcu callback to free a maple node | |
182 | * @node: The node to free | |
183 | * | |
184 | * The maple tree uses the parent pointer to indicate this node is no longer in | |
185 | * use and will be freed. | |
186 | */ | |
187 | static void ma_free_rcu(struct maple_node *node) | |
188 | { | |
c13af03d | 189 | WARN_ON(node->parent != ma_parent_ptr(node)); |
54a611b6 LH |
190 | call_rcu(&node->rcu, mt_free_rcu); |
191 | } | |
192 | ||
54a611b6 LH |
193 | static void mas_set_height(struct ma_state *mas) |
194 | { | |
195 | unsigned int new_flags = mas->tree->ma_flags; | |
196 | ||
197 | new_flags &= ~MT_FLAGS_HEIGHT_MASK; | |
5950ada9 | 198 | MAS_BUG_ON(mas, mas->depth > MAPLE_HEIGHT_MAX); |
54a611b6 LH |
199 | new_flags |= mas->depth << MT_FLAGS_HEIGHT_OFFSET; |
200 | mas->tree->ma_flags = new_flags; | |
201 | } | |
202 | ||
203 | static unsigned int mas_mt_height(struct ma_state *mas) | |
204 | { | |
205 | return mt_height(mas->tree); | |
206 | } | |
207 | ||
208 | static inline enum maple_type mte_node_type(const struct maple_enode *entry) | |
209 | { | |
210 | return ((unsigned long)entry >> MAPLE_NODE_TYPE_SHIFT) & | |
211 | MAPLE_NODE_TYPE_MASK; | |
212 | } | |
213 | ||
214 | static inline bool ma_is_dense(const enum maple_type type) | |
215 | { | |
216 | return type < maple_leaf_64; | |
217 | } | |
218 | ||
219 | static inline bool ma_is_leaf(const enum maple_type type) | |
220 | { | |
221 | return type < maple_range_64; | |
222 | } | |
223 | ||
224 | static inline bool mte_is_leaf(const struct maple_enode *entry) | |
225 | { | |
226 | return ma_is_leaf(mte_node_type(entry)); | |
227 | } | |
228 | ||
229 | /* | |
230 | * We also reserve values with the bottom two bits set to '10' which are | |
231 | * below 4096 | |
232 | */ | |
233 | static inline bool mt_is_reserved(const void *entry) | |
234 | { | |
235 | return ((unsigned long)entry < MAPLE_RESERVED_RANGE) && | |
236 | xa_is_internal(entry); | |
237 | } | |
238 | ||
239 | static inline void mas_set_err(struct ma_state *mas, long err) | |
240 | { | |
241 | mas->node = MA_ERROR(err); | |
242 | } | |
243 | ||
f0a1f866 | 244 | static inline bool mas_is_ptr(const struct ma_state *mas) |
54a611b6 LH |
245 | { |
246 | return mas->node == MAS_ROOT; | |
247 | } | |
248 | ||
f0a1f866 | 249 | static inline bool mas_is_start(const struct ma_state *mas) |
54a611b6 LH |
250 | { |
251 | return mas->node == MAS_START; | |
252 | } | |
253 | ||
254 | bool mas_is_err(struct ma_state *mas) | |
255 | { | |
256 | return xa_is_err(mas->node); | |
257 | } | |
258 | ||
a8091f03 LH |
259 | static __always_inline bool mas_is_overflow(struct ma_state *mas) |
260 | { | |
261 | if (unlikely(mas->node == MAS_OVERFLOW)) | |
262 | return true; | |
263 | ||
264 | return false; | |
265 | } | |
266 | ||
267 | static __always_inline bool mas_is_underflow(struct ma_state *mas) | |
268 | { | |
269 | if (unlikely(mas->node == MAS_UNDERFLOW)) | |
270 | return true; | |
271 | ||
272 | return false; | |
273 | } | |
274 | ||
54a611b6 LH |
275 | static inline bool mas_searchable(struct ma_state *mas) |
276 | { | |
277 | if (mas_is_none(mas)) | |
278 | return false; | |
279 | ||
280 | if (mas_is_ptr(mas)) | |
281 | return false; | |
282 | ||
283 | return true; | |
284 | } | |
285 | ||
286 | static inline struct maple_node *mte_to_node(const struct maple_enode *entry) | |
287 | { | |
288 | return (struct maple_node *)((unsigned long)entry & ~MAPLE_NODE_MASK); | |
289 | } | |
290 | ||
291 | /* | |
292 | * mte_to_mat() - Convert a maple encoded node to a maple topiary node. | |
293 | * @entry: The maple encoded node | |
294 | * | |
295 | * Return: a maple topiary pointer | |
296 | */ | |
297 | static inline struct maple_topiary *mte_to_mat(const struct maple_enode *entry) | |
298 | { | |
299 | return (struct maple_topiary *) | |
300 | ((unsigned long)entry & ~MAPLE_NODE_MASK); | |
301 | } | |
302 | ||
303 | /* | |
304 | * mas_mn() - Get the maple state node. | |
305 | * @mas: The maple state | |
306 | * | |
307 | * Return: the maple node (not encoded - bare pointer). | |
308 | */ | |
309 | static inline struct maple_node *mas_mn(const struct ma_state *mas) | |
310 | { | |
311 | return mte_to_node(mas->node); | |
312 | } | |
313 | ||
314 | /* | |
315 | * mte_set_node_dead() - Set a maple encoded node as dead. | |
316 | * @mn: The maple encoded node. | |
317 | */ | |
318 | static inline void mte_set_node_dead(struct maple_enode *mn) | |
319 | { | |
320 | mte_to_node(mn)->parent = ma_parent_ptr(mte_to_node(mn)); | |
321 | smp_wmb(); /* Needed for RCU */ | |
322 | } | |
323 | ||
324 | /* Bit 1 indicates the root is a node */ | |
325 | #define MAPLE_ROOT_NODE 0x02 | |
326 | /* maple_type stored bit 3-6 */ | |
327 | #define MAPLE_ENODE_TYPE_SHIFT 0x03 | |
328 | /* Bit 2 means a NULL somewhere below */ | |
329 | #define MAPLE_ENODE_NULL 0x04 | |
330 | ||
331 | static inline struct maple_enode *mt_mk_node(const struct maple_node *node, | |
332 | enum maple_type type) | |
333 | { | |
334 | return (void *)((unsigned long)node | | |
335 | (type << MAPLE_ENODE_TYPE_SHIFT) | MAPLE_ENODE_NULL); | |
336 | } | |
337 | ||
338 | static inline void *mte_mk_root(const struct maple_enode *node) | |
339 | { | |
340 | return (void *)((unsigned long)node | MAPLE_ROOT_NODE); | |
341 | } | |
342 | ||
343 | static inline void *mte_safe_root(const struct maple_enode *node) | |
344 | { | |
345 | return (void *)((unsigned long)node & ~MAPLE_ROOT_NODE); | |
346 | } | |
347 | ||
6e7ba8b5 | 348 | static inline void *mte_set_full(const struct maple_enode *node) |
54a611b6 | 349 | { |
6e7ba8b5 | 350 | return (void *)((unsigned long)node & ~MAPLE_ENODE_NULL); |
54a611b6 LH |
351 | } |
352 | ||
6e7ba8b5 | 353 | static inline void *mte_clear_full(const struct maple_enode *node) |
54a611b6 | 354 | { |
6e7ba8b5 LH |
355 | return (void *)((unsigned long)node | MAPLE_ENODE_NULL); |
356 | } | |
357 | ||
358 | static inline bool mte_has_null(const struct maple_enode *node) | |
359 | { | |
360 | return (unsigned long)node & MAPLE_ENODE_NULL; | |
54a611b6 LH |
361 | } |
362 | ||
363 | static inline bool ma_is_root(struct maple_node *node) | |
364 | { | |
365 | return ((unsigned long)node->parent & MA_ROOT_PARENT); | |
366 | } | |
367 | ||
368 | static inline bool mte_is_root(const struct maple_enode *node) | |
369 | { | |
370 | return ma_is_root(mte_to_node(node)); | |
371 | } | |
372 | ||
373 | static inline bool mas_is_root_limits(const struct ma_state *mas) | |
374 | { | |
375 | return !mas->min && mas->max == ULONG_MAX; | |
376 | } | |
377 | ||
378 | static inline bool mt_is_alloc(struct maple_tree *mt) | |
379 | { | |
380 | return (mt->ma_flags & MT_FLAGS_ALLOC_RANGE); | |
381 | } | |
382 | ||
383 | /* | |
384 | * The Parent Pointer | |
385 | * Excluding root, the parent pointer is 256B aligned like all other tree nodes. | |
386 | * When storing a 32 or 64 bit values, the offset can fit into 5 bits. The 16 | |
387 | * bit values need an extra bit to store the offset. This extra bit comes from | |
388 | * a reuse of the last bit in the node type. This is possible by using bit 1 to | |
389 | * indicate if bit 2 is part of the type or the slot. | |
390 | * | |
391 | * Note types: | |
392 | * 0x??1 = Root | |
393 | * 0x?00 = 16 bit nodes | |
394 | * 0x010 = 32 bit nodes | |
395 | * 0x110 = 64 bit nodes | |
396 | * | |
397 | * Slot size and alignment | |
398 | * 0b??1 : Root | |
399 | * 0b?00 : 16 bit values, type in 0-1, slot in 2-7 | |
400 | * 0b010 : 32 bit values, type in 0-2, slot in 3-7 | |
401 | * 0b110 : 64 bit values, type in 0-2, slot in 3-7 | |
402 | */ | |
403 | ||
404 | #define MAPLE_PARENT_ROOT 0x01 | |
405 | ||
406 | #define MAPLE_PARENT_SLOT_SHIFT 0x03 | |
407 | #define MAPLE_PARENT_SLOT_MASK 0xF8 | |
408 | ||
409 | #define MAPLE_PARENT_16B_SLOT_SHIFT 0x02 | |
410 | #define MAPLE_PARENT_16B_SLOT_MASK 0xFC | |
411 | ||
412 | #define MAPLE_PARENT_RANGE64 0x06 | |
413 | #define MAPLE_PARENT_RANGE32 0x04 | |
414 | #define MAPLE_PARENT_NOT_RANGE16 0x02 | |
415 | ||
416 | /* | |
417 | * mte_parent_shift() - Get the parent shift for the slot storage. | |
418 | * @parent: The parent pointer cast as an unsigned long | |
419 | * Return: The shift into that pointer to the star to of the slot | |
420 | */ | |
421 | static inline unsigned long mte_parent_shift(unsigned long parent) | |
422 | { | |
423 | /* Note bit 1 == 0 means 16B */ | |
424 | if (likely(parent & MAPLE_PARENT_NOT_RANGE16)) | |
425 | return MAPLE_PARENT_SLOT_SHIFT; | |
426 | ||
427 | return MAPLE_PARENT_16B_SLOT_SHIFT; | |
428 | } | |
429 | ||
430 | /* | |
431 | * mte_parent_slot_mask() - Get the slot mask for the parent. | |
432 | * @parent: The parent pointer cast as an unsigned long. | |
433 | * Return: The slot mask for that parent. | |
434 | */ | |
435 | static inline unsigned long mte_parent_slot_mask(unsigned long parent) | |
436 | { | |
437 | /* Note bit 1 == 0 means 16B */ | |
438 | if (likely(parent & MAPLE_PARENT_NOT_RANGE16)) | |
439 | return MAPLE_PARENT_SLOT_MASK; | |
440 | ||
441 | return MAPLE_PARENT_16B_SLOT_MASK; | |
442 | } | |
443 | ||
444 | /* | |
afc754c6 | 445 | * mas_parent_type() - Return the maple_type of the parent from the stored |
54a611b6 LH |
446 | * parent type. |
447 | * @mas: The maple state | |
afc754c6 | 448 | * @enode: The maple_enode to extract the parent's enum |
54a611b6 LH |
449 | * Return: The node->parent maple_type |
450 | */ | |
451 | static inline | |
afc754c6 | 452 | enum maple_type mas_parent_type(struct ma_state *mas, struct maple_enode *enode) |
54a611b6 LH |
453 | { |
454 | unsigned long p_type; | |
455 | ||
afc754c6 LH |
456 | p_type = (unsigned long)mte_to_node(enode)->parent; |
457 | if (WARN_ON(p_type & MAPLE_PARENT_ROOT)) | |
458 | return 0; | |
54a611b6 LH |
459 | |
460 | p_type &= MAPLE_NODE_MASK; | |
afc754c6 | 461 | p_type &= ~mte_parent_slot_mask(p_type); |
54a611b6 LH |
462 | switch (p_type) { |
463 | case MAPLE_PARENT_RANGE64: /* or MAPLE_PARENT_ARANGE64 */ | |
afc754c6 | 464 | if (mt_is_alloc(mas->tree)) |
54a611b6 LH |
465 | return maple_arange_64; |
466 | return maple_range_64; | |
467 | } | |
468 | ||
469 | return 0; | |
470 | } | |
471 | ||
54a611b6 | 472 | /* |
bf96715e | 473 | * mas_set_parent() - Set the parent node and encode the slot |
54a611b6 LH |
474 | * @enode: The encoded maple node. |
475 | * @parent: The encoded maple node that is the parent of @enode. | |
476 | * @slot: The slot that @enode resides in @parent. | |
477 | * | |
478 | * Slot number is encoded in the enode->parent bit 3-6 or 2-6, depending on the | |
479 | * parent type. | |
480 | */ | |
481 | static inline | |
bf96715e LH |
482 | void mas_set_parent(struct ma_state *mas, struct maple_enode *enode, |
483 | const struct maple_enode *parent, unsigned char slot) | |
54a611b6 | 484 | { |
831978e3 | 485 | unsigned long val = (unsigned long)parent; |
54a611b6 LH |
486 | unsigned long shift; |
487 | unsigned long type; | |
488 | enum maple_type p_type = mte_node_type(parent); | |
489 | ||
bf96715e LH |
490 | MAS_BUG_ON(mas, p_type == maple_dense); |
491 | MAS_BUG_ON(mas, p_type == maple_leaf_64); | |
54a611b6 LH |
492 | |
493 | switch (p_type) { | |
494 | case maple_range_64: | |
495 | case maple_arange_64: | |
496 | shift = MAPLE_PARENT_SLOT_SHIFT; | |
497 | type = MAPLE_PARENT_RANGE64; | |
498 | break; | |
499 | default: | |
500 | case maple_dense: | |
501 | case maple_leaf_64: | |
502 | shift = type = 0; | |
503 | break; | |
504 | } | |
505 | ||
506 | val &= ~MAPLE_NODE_MASK; /* Clear all node metadata in parent */ | |
507 | val |= (slot << shift) | type; | |
508 | mte_to_node(enode)->parent = ma_parent_ptr(val); | |
509 | } | |
510 | ||
511 | /* | |
512 | * mte_parent_slot() - get the parent slot of @enode. | |
513 | * @enode: The encoded maple node. | |
514 | * | |
515 | * Return: The slot in the parent node where @enode resides. | |
516 | */ | |
517 | static inline unsigned int mte_parent_slot(const struct maple_enode *enode) | |
518 | { | |
831978e3 | 519 | unsigned long val = (unsigned long)mte_to_node(enode)->parent; |
54a611b6 | 520 | |
84fd3e1e | 521 | if (val & MA_ROOT_PARENT) |
54a611b6 LH |
522 | return 0; |
523 | ||
524 | /* | |
525 | * Okay to use MAPLE_PARENT_16B_SLOT_MASK as the last bit will be lost | |
526 | * by shift if the parent shift is MAPLE_PARENT_SLOT_SHIFT | |
527 | */ | |
528 | return (val & MAPLE_PARENT_16B_SLOT_MASK) >> mte_parent_shift(val); | |
529 | } | |
530 | ||
531 | /* | |
532 | * mte_parent() - Get the parent of @node. | |
533 | * @node: The encoded maple node. | |
534 | * | |
535 | * Return: The parent maple node. | |
536 | */ | |
537 | static inline struct maple_node *mte_parent(const struct maple_enode *enode) | |
538 | { | |
539 | return (void *)((unsigned long) | |
540 | (mte_to_node(enode)->parent) & ~MAPLE_NODE_MASK); | |
541 | } | |
542 | ||
543 | /* | |
544 | * ma_dead_node() - check if the @enode is dead. | |
545 | * @enode: The encoded maple node | |
546 | * | |
547 | * Return: true if dead, false otherwise. | |
548 | */ | |
549 | static inline bool ma_dead_node(const struct maple_node *node) | |
550 | { | |
0a2b18d9 | 551 | struct maple_node *parent; |
54a611b6 | 552 | |
0a2b18d9 LH |
553 | /* Do not reorder reads from the node prior to the parent check */ |
554 | smp_rmb(); | |
555 | parent = (void *)((unsigned long) node->parent & ~MAPLE_NODE_MASK); | |
54a611b6 LH |
556 | return (parent == node); |
557 | } | |
39d0bd86 | 558 | |
54a611b6 LH |
559 | /* |
560 | * mte_dead_node() - check if the @enode is dead. | |
561 | * @enode: The encoded maple node | |
562 | * | |
563 | * Return: true if dead, false otherwise. | |
564 | */ | |
565 | static inline bool mte_dead_node(const struct maple_enode *enode) | |
566 | { | |
567 | struct maple_node *parent, *node; | |
568 | ||
569 | node = mte_to_node(enode); | |
0a2b18d9 LH |
570 | /* Do not reorder reads from the node prior to the parent check */ |
571 | smp_rmb(); | |
54a611b6 LH |
572 | parent = mte_parent(enode); |
573 | return (parent == node); | |
574 | } | |
575 | ||
576 | /* | |
577 | * mas_allocated() - Get the number of nodes allocated in a maple state. | |
578 | * @mas: The maple state | |
579 | * | |
580 | * The ma_state alloc member is overloaded to hold a pointer to the first | |
581 | * allocated node or to the number of requested nodes to allocate. If bit 0 is | |
582 | * set, then the alloc contains the number of requested nodes. If there is an | |
583 | * allocated node, then the total allocated nodes is in that node. | |
584 | * | |
585 | * Return: The total number of nodes allocated | |
586 | */ | |
587 | static inline unsigned long mas_allocated(const struct ma_state *mas) | |
588 | { | |
589 | if (!mas->alloc || ((unsigned long)mas->alloc & 0x1)) | |
590 | return 0; | |
591 | ||
592 | return mas->alloc->total; | |
593 | } | |
594 | ||
595 | /* | |
596 | * mas_set_alloc_req() - Set the requested number of allocations. | |
597 | * @mas: the maple state | |
598 | * @count: the number of allocations. | |
599 | * | |
600 | * The requested number of allocations is either in the first allocated node, | |
601 | * located in @mas->alloc->request_count, or directly in @mas->alloc if there is | |
602 | * no allocated node. Set the request either in the node or do the necessary | |
603 | * encoding to store in @mas->alloc directly. | |
604 | */ | |
605 | static inline void mas_set_alloc_req(struct ma_state *mas, unsigned long count) | |
606 | { | |
607 | if (!mas->alloc || ((unsigned long)mas->alloc & 0x1)) { | |
608 | if (!count) | |
609 | mas->alloc = NULL; | |
610 | else | |
611 | mas->alloc = (struct maple_alloc *)(((count) << 1U) | 1U); | |
612 | return; | |
613 | } | |
614 | ||
615 | mas->alloc->request_count = count; | |
616 | } | |
617 | ||
618 | /* | |
619 | * mas_alloc_req() - get the requested number of allocations. | |
620 | * @mas: The maple state | |
621 | * | |
622 | * The alloc count is either stored directly in @mas, or in | |
623 | * @mas->alloc->request_count if there is at least one node allocated. Decode | |
624 | * the request count if it's stored directly in @mas->alloc. | |
625 | * | |
626 | * Return: The allocation request count. | |
627 | */ | |
628 | static inline unsigned int mas_alloc_req(const struct ma_state *mas) | |
629 | { | |
630 | if ((unsigned long)mas->alloc & 0x1) | |
631 | return (unsigned long)(mas->alloc) >> 1; | |
632 | else if (mas->alloc) | |
633 | return mas->alloc->request_count; | |
634 | return 0; | |
635 | } | |
636 | ||
637 | /* | |
638 | * ma_pivots() - Get a pointer to the maple node pivots. | |
639 | * @node - the maple node | |
640 | * @type - the node type | |
641 | * | |
39d0bd86 LH |
642 | * In the event of a dead node, this array may be %NULL |
643 | * | |
54a611b6 LH |
644 | * Return: A pointer to the maple node pivots |
645 | */ | |
646 | static inline unsigned long *ma_pivots(struct maple_node *node, | |
647 | enum maple_type type) | |
648 | { | |
649 | switch (type) { | |
650 | case maple_arange_64: | |
651 | return node->ma64.pivot; | |
652 | case maple_range_64: | |
653 | case maple_leaf_64: | |
654 | return node->mr64.pivot; | |
655 | case maple_dense: | |
656 | return NULL; | |
657 | } | |
658 | return NULL; | |
659 | } | |
660 | ||
661 | /* | |
662 | * ma_gaps() - Get a pointer to the maple node gaps. | |
663 | * @node - the maple node | |
664 | * @type - the node type | |
665 | * | |
666 | * Return: A pointer to the maple node gaps | |
667 | */ | |
668 | static inline unsigned long *ma_gaps(struct maple_node *node, | |
669 | enum maple_type type) | |
670 | { | |
671 | switch (type) { | |
672 | case maple_arange_64: | |
673 | return node->ma64.gap; | |
674 | case maple_range_64: | |
675 | case maple_leaf_64: | |
676 | case maple_dense: | |
677 | return NULL; | |
678 | } | |
679 | return NULL; | |
680 | } | |
681 | ||
682 | /* | |
acd4de60 LH |
683 | * mas_pivot() - Get the pivot at @piv of the maple encoded node. |
684 | * @mas: The maple state. | |
54a611b6 LH |
685 | * @piv: The pivot. |
686 | * | |
687 | * Return: the pivot at @piv of @mn. | |
688 | */ | |
acd4de60 | 689 | static inline unsigned long mas_pivot(struct ma_state *mas, unsigned char piv) |
54a611b6 | 690 | { |
acd4de60 LH |
691 | struct maple_node *node = mas_mn(mas); |
692 | enum maple_type type = mte_node_type(mas->node); | |
54a611b6 | 693 | |
acd4de60 LH |
694 | if (MAS_WARN_ON(mas, piv >= mt_pivots[type])) { |
695 | mas_set_err(mas, -EIO); | |
54a611b6 LH |
696 | return 0; |
697 | } | |
acd4de60 | 698 | |
ab6ef70a | 699 | switch (type) { |
54a611b6 LH |
700 | case maple_arange_64: |
701 | return node->ma64.pivot[piv]; | |
702 | case maple_range_64: | |
703 | case maple_leaf_64: | |
704 | return node->mr64.pivot[piv]; | |
705 | case maple_dense: | |
706 | return 0; | |
707 | } | |
708 | return 0; | |
709 | } | |
710 | ||
711 | /* | |
712 | * mas_safe_pivot() - get the pivot at @piv or mas->max. | |
713 | * @mas: The maple state | |
714 | * @pivots: The pointer to the maple node pivots | |
715 | * @piv: The pivot to fetch | |
716 | * @type: The maple node type | |
717 | * | |
718 | * Return: The pivot at @piv within the limit of the @pivots array, @mas->max | |
719 | * otherwise. | |
720 | */ | |
721 | static inline unsigned long | |
722 | mas_safe_pivot(const struct ma_state *mas, unsigned long *pivots, | |
723 | unsigned char piv, enum maple_type type) | |
724 | { | |
725 | if (piv >= mt_pivots[type]) | |
726 | return mas->max; | |
727 | ||
728 | return pivots[piv]; | |
729 | } | |
730 | ||
731 | /* | |
732 | * mas_safe_min() - Return the minimum for a given offset. | |
733 | * @mas: The maple state | |
734 | * @pivots: The pointer to the maple node pivots | |
735 | * @offset: The offset into the pivot array | |
736 | * | |
737 | * Return: The minimum range value that is contained in @offset. | |
738 | */ | |
739 | static inline unsigned long | |
740 | mas_safe_min(struct ma_state *mas, unsigned long *pivots, unsigned char offset) | |
741 | { | |
742 | if (likely(offset)) | |
743 | return pivots[offset - 1] + 1; | |
744 | ||
745 | return mas->min; | |
746 | } | |
747 | ||
54a611b6 LH |
748 | /* |
749 | * mte_set_pivot() - Set a pivot to a value in an encoded maple node. | |
750 | * @mn: The encoded maple node | |
751 | * @piv: The pivot offset | |
752 | * @val: The value of the pivot | |
753 | */ | |
754 | static inline void mte_set_pivot(struct maple_enode *mn, unsigned char piv, | |
755 | unsigned long val) | |
756 | { | |
757 | struct maple_node *node = mte_to_node(mn); | |
758 | enum maple_type type = mte_node_type(mn); | |
759 | ||
760 | BUG_ON(piv >= mt_pivots[type]); | |
761 | switch (type) { | |
762 | default: | |
763 | case maple_range_64: | |
764 | case maple_leaf_64: | |
765 | node->mr64.pivot[piv] = val; | |
766 | break; | |
767 | case maple_arange_64: | |
768 | node->ma64.pivot[piv] = val; | |
769 | break; | |
770 | case maple_dense: | |
771 | break; | |
772 | } | |
773 | ||
774 | } | |
775 | ||
776 | /* | |
777 | * ma_slots() - Get a pointer to the maple node slots. | |
778 | * @mn: The maple node | |
779 | * @mt: The maple node type | |
780 | * | |
781 | * Return: A pointer to the maple node slots | |
782 | */ | |
783 | static inline void __rcu **ma_slots(struct maple_node *mn, enum maple_type mt) | |
784 | { | |
785 | switch (mt) { | |
786 | default: | |
787 | case maple_arange_64: | |
788 | return mn->ma64.slot; | |
789 | case maple_range_64: | |
790 | case maple_leaf_64: | |
791 | return mn->mr64.slot; | |
792 | case maple_dense: | |
793 | return mn->slot; | |
794 | } | |
795 | } | |
796 | ||
19a462f0 LH |
797 | static inline bool mt_write_locked(const struct maple_tree *mt) |
798 | { | |
799 | return mt_external_lock(mt) ? mt_write_lock_is_held(mt) : | |
800 | lockdep_is_held(&mt->ma_lock); | |
801 | } | |
802 | ||
54a611b6 LH |
803 | static inline bool mt_locked(const struct maple_tree *mt) |
804 | { | |
805 | return mt_external_lock(mt) ? mt_lock_is_held(mt) : | |
806 | lockdep_is_held(&mt->ma_lock); | |
807 | } | |
808 | ||
809 | static inline void *mt_slot(const struct maple_tree *mt, | |
810 | void __rcu **slots, unsigned char offset) | |
811 | { | |
812 | return rcu_dereference_check(slots[offset], mt_locked(mt)); | |
813 | } | |
814 | ||
790e1fa8 LH |
815 | static inline void *mt_slot_locked(struct maple_tree *mt, void __rcu **slots, |
816 | unsigned char offset) | |
817 | { | |
19a462f0 | 818 | return rcu_dereference_protected(slots[offset], mt_write_locked(mt)); |
790e1fa8 | 819 | } |
54a611b6 LH |
820 | /* |
821 | * mas_slot_locked() - Get the slot value when holding the maple tree lock. | |
822 | * @mas: The maple state | |
823 | * @slots: The pointer to the slots | |
824 | * @offset: The offset into the slots array to fetch | |
825 | * | |
826 | * Return: The entry stored in @slots at the @offset. | |
827 | */ | |
828 | static inline void *mas_slot_locked(struct ma_state *mas, void __rcu **slots, | |
829 | unsigned char offset) | |
830 | { | |
790e1fa8 | 831 | return mt_slot_locked(mas->tree, slots, offset); |
54a611b6 LH |
832 | } |
833 | ||
834 | /* | |
835 | * mas_slot() - Get the slot value when not holding the maple tree lock. | |
836 | * @mas: The maple state | |
837 | * @slots: The pointer to the slots | |
838 | * @offset: The offset into the slots array to fetch | |
839 | * | |
840 | * Return: The entry stored in @slots at the @offset | |
841 | */ | |
842 | static inline void *mas_slot(struct ma_state *mas, void __rcu **slots, | |
843 | unsigned char offset) | |
844 | { | |
845 | return mt_slot(mas->tree, slots, offset); | |
846 | } | |
847 | ||
848 | /* | |
849 | * mas_root() - Get the maple tree root. | |
850 | * @mas: The maple state. | |
851 | * | |
852 | * Return: The pointer to the root of the tree | |
853 | */ | |
854 | static inline void *mas_root(struct ma_state *mas) | |
855 | { | |
856 | return rcu_dereference_check(mas->tree->ma_root, mt_locked(mas->tree)); | |
857 | } | |
858 | ||
859 | static inline void *mt_root_locked(struct maple_tree *mt) | |
860 | { | |
19a462f0 | 861 | return rcu_dereference_protected(mt->ma_root, mt_write_locked(mt)); |
54a611b6 LH |
862 | } |
863 | ||
864 | /* | |
865 | * mas_root_locked() - Get the maple tree root when holding the maple tree lock. | |
866 | * @mas: The maple state. | |
867 | * | |
868 | * Return: The pointer to the root of the tree | |
869 | */ | |
870 | static inline void *mas_root_locked(struct ma_state *mas) | |
871 | { | |
872 | return mt_root_locked(mas->tree); | |
873 | } | |
874 | ||
875 | static inline struct maple_metadata *ma_meta(struct maple_node *mn, | |
876 | enum maple_type mt) | |
877 | { | |
878 | switch (mt) { | |
879 | case maple_arange_64: | |
880 | return &mn->ma64.meta; | |
881 | default: | |
882 | return &mn->mr64.meta; | |
883 | } | |
884 | } | |
885 | ||
886 | /* | |
887 | * ma_set_meta() - Set the metadata information of a node. | |
888 | * @mn: The maple node | |
889 | * @mt: The maple node type | |
890 | * @offset: The offset of the highest sub-gap in this node. | |
891 | * @end: The end of the data in this node. | |
892 | */ | |
893 | static inline void ma_set_meta(struct maple_node *mn, enum maple_type mt, | |
894 | unsigned char offset, unsigned char end) | |
895 | { | |
896 | struct maple_metadata *meta = ma_meta(mn, mt); | |
897 | ||
898 | meta->gap = offset; | |
899 | meta->end = end; | |
900 | } | |
901 | ||
2e5b4921 | 902 | /* |
790e1fa8 LH |
903 | * mt_clear_meta() - clear the metadata information of a node, if it exists |
904 | * @mt: The maple tree | |
2e5b4921 | 905 | * @mn: The maple node |
790e1fa8 | 906 | * @type: The maple node type |
2e5b4921 LH |
907 | * @offset: The offset of the highest sub-gap in this node. |
908 | * @end: The end of the data in this node. | |
909 | */ | |
790e1fa8 LH |
910 | static inline void mt_clear_meta(struct maple_tree *mt, struct maple_node *mn, |
911 | enum maple_type type) | |
2e5b4921 LH |
912 | { |
913 | struct maple_metadata *meta; | |
914 | unsigned long *pivots; | |
915 | void __rcu **slots; | |
916 | void *next; | |
917 | ||
790e1fa8 | 918 | switch (type) { |
2e5b4921 LH |
919 | case maple_range_64: |
920 | pivots = mn->mr64.pivot; | |
921 | if (unlikely(pivots[MAPLE_RANGE64_SLOTS - 2])) { | |
922 | slots = mn->mr64.slot; | |
790e1fa8 LH |
923 | next = mt_slot_locked(mt, slots, |
924 | MAPLE_RANGE64_SLOTS - 1); | |
925 | if (unlikely((mte_to_node(next) && | |
926 | mte_node_type(next)))) | |
927 | return; /* no metadata, could be node */ | |
2e5b4921 LH |
928 | } |
929 | fallthrough; | |
930 | case maple_arange_64: | |
790e1fa8 | 931 | meta = ma_meta(mn, type); |
2e5b4921 LH |
932 | break; |
933 | default: | |
934 | return; | |
935 | } | |
936 | ||
937 | meta->gap = 0; | |
938 | meta->end = 0; | |
939 | } | |
940 | ||
54a611b6 LH |
941 | /* |
942 | * ma_meta_end() - Get the data end of a node from the metadata | |
943 | * @mn: The maple node | |
944 | * @mt: The maple node type | |
945 | */ | |
946 | static inline unsigned char ma_meta_end(struct maple_node *mn, | |
947 | enum maple_type mt) | |
948 | { | |
949 | struct maple_metadata *meta = ma_meta(mn, mt); | |
950 | ||
951 | return meta->end; | |
952 | } | |
953 | ||
954 | /* | |
955 | * ma_meta_gap() - Get the largest gap location of a node from the metadata | |
956 | * @mn: The maple node | |
957 | * @mt: The maple node type | |
958 | */ | |
959 | static inline unsigned char ma_meta_gap(struct maple_node *mn, | |
960 | enum maple_type mt) | |
961 | { | |
54a611b6 LH |
962 | return mn->ma64.meta.gap; |
963 | } | |
964 | ||
965 | /* | |
966 | * ma_set_meta_gap() - Set the largest gap location in a nodes metadata | |
967 | * @mn: The maple node | |
968 | * @mn: The maple node type | |
969 | * @offset: The location of the largest gap. | |
970 | */ | |
971 | static inline void ma_set_meta_gap(struct maple_node *mn, enum maple_type mt, | |
972 | unsigned char offset) | |
973 | { | |
974 | ||
975 | struct maple_metadata *meta = ma_meta(mn, mt); | |
976 | ||
977 | meta->gap = offset; | |
978 | } | |
979 | ||
980 | /* | |
981 | * mat_add() - Add a @dead_enode to the ma_topiary of a list of dead nodes. | |
982 | * @mat - the ma_topiary, a linked list of dead nodes. | |
983 | * @dead_enode - the node to be marked as dead and added to the tail of the list | |
984 | * | |
985 | * Add the @dead_enode to the linked list in @mat. | |
986 | */ | |
987 | static inline void mat_add(struct ma_topiary *mat, | |
988 | struct maple_enode *dead_enode) | |
989 | { | |
990 | mte_set_node_dead(dead_enode); | |
991 | mte_to_mat(dead_enode)->next = NULL; | |
992 | if (!mat->tail) { | |
993 | mat->tail = mat->head = dead_enode; | |
994 | return; | |
995 | } | |
996 | ||
997 | mte_to_mat(mat->tail)->next = dead_enode; | |
998 | mat->tail = dead_enode; | |
999 | } | |
1000 | ||
530f745c LH |
1001 | static void mt_free_walk(struct rcu_head *head); |
1002 | static void mt_destroy_walk(struct maple_enode *enode, struct maple_tree *mt, | |
1003 | bool free); | |
54a611b6 LH |
1004 | /* |
1005 | * mas_mat_destroy() - Free all nodes and subtrees in a dead list. | |
1006 | * @mas - the maple state | |
1007 | * @mat - the ma_topiary linked list of dead nodes to free. | |
1008 | * | |
1009 | * Destroy walk a dead list. | |
1010 | */ | |
1011 | static void mas_mat_destroy(struct ma_state *mas, struct ma_topiary *mat) | |
1012 | { | |
1013 | struct maple_enode *next; | |
530f745c LH |
1014 | struct maple_node *node; |
1015 | bool in_rcu = mt_in_rcu(mas->tree); | |
54a611b6 LH |
1016 | |
1017 | while (mat->head) { | |
1018 | next = mte_to_mat(mat->head)->next; | |
530f745c LH |
1019 | node = mte_to_node(mat->head); |
1020 | mt_destroy_walk(mat->head, mas->tree, !in_rcu); | |
1021 | if (in_rcu) | |
1022 | call_rcu(&node->rcu, mt_free_walk); | |
54a611b6 LH |
1023 | mat->head = next; |
1024 | } | |
1025 | } | |
1026 | /* | |
1027 | * mas_descend() - Descend into the slot stored in the ma_state. | |
1028 | * @mas - the maple state. | |
1029 | * | |
1030 | * Note: Not RCU safe, only use in write side or debug code. | |
1031 | */ | |
1032 | static inline void mas_descend(struct ma_state *mas) | |
1033 | { | |
1034 | enum maple_type type; | |
1035 | unsigned long *pivots; | |
1036 | struct maple_node *node; | |
1037 | void __rcu **slots; | |
1038 | ||
1039 | node = mas_mn(mas); | |
1040 | type = mte_node_type(mas->node); | |
1041 | pivots = ma_pivots(node, type); | |
1042 | slots = ma_slots(node, type); | |
1043 | ||
1044 | if (mas->offset) | |
1045 | mas->min = pivots[mas->offset - 1] + 1; | |
1046 | mas->max = mas_safe_pivot(mas, pivots, mas->offset, type); | |
1047 | mas->node = mas_slot(mas, slots, mas->offset); | |
1048 | } | |
1049 | ||
1050 | /* | |
1051 | * mte_set_gap() - Set a maple node gap. | |
1052 | * @mn: The encoded maple node | |
1053 | * @gap: The offset of the gap to set | |
1054 | * @val: The gap value | |
1055 | */ | |
1056 | static inline void mte_set_gap(const struct maple_enode *mn, | |
1057 | unsigned char gap, unsigned long val) | |
1058 | { | |
1059 | switch (mte_node_type(mn)) { | |
1060 | default: | |
1061 | break; | |
1062 | case maple_arange_64: | |
1063 | mte_to_node(mn)->ma64.gap[gap] = val; | |
1064 | break; | |
1065 | } | |
1066 | } | |
1067 | ||
1068 | /* | |
1069 | * mas_ascend() - Walk up a level of the tree. | |
1070 | * @mas: The maple state | |
1071 | * | |
1072 | * Sets the @mas->max and @mas->min to the correct values when walking up. This | |
1073 | * may cause several levels of walking up to find the correct min and max. | |
1074 | * May find a dead node which will cause a premature return. | |
1075 | * Return: 1 on dead node, 0 otherwise | |
1076 | */ | |
1077 | static int mas_ascend(struct ma_state *mas) | |
1078 | { | |
1079 | struct maple_enode *p_enode; /* parent enode. */ | |
1080 | struct maple_enode *a_enode; /* ancestor enode. */ | |
1081 | struct maple_node *a_node; /* ancestor node. */ | |
1082 | struct maple_node *p_node; /* parent node. */ | |
1083 | unsigned char a_slot; | |
1084 | enum maple_type a_type; | |
1085 | unsigned long min, max; | |
1086 | unsigned long *pivots; | |
54a611b6 LH |
1087 | bool set_max = false, set_min = false; |
1088 | ||
1089 | a_node = mas_mn(mas); | |
1090 | if (ma_is_root(a_node)) { | |
1091 | mas->offset = 0; | |
1092 | return 0; | |
1093 | } | |
1094 | ||
1095 | p_node = mte_parent(mas->node); | |
1096 | if (unlikely(a_node == p_node)) | |
1097 | return 1; | |
633769c9 | 1098 | |
afc754c6 | 1099 | a_type = mas_parent_type(mas, mas->node); |
633769c9 | 1100 | mas->offset = mte_parent_slot(mas->node); |
54a611b6 LH |
1101 | a_enode = mt_mk_node(p_node, a_type); |
1102 | ||
1103 | /* Check to make sure all parent information is still accurate */ | |
1104 | if (p_node != mte_parent(mas->node)) | |
1105 | return 1; | |
1106 | ||
1107 | mas->node = a_enode; | |
54a611b6 LH |
1108 | |
1109 | if (mte_is_root(a_enode)) { | |
1110 | mas->max = ULONG_MAX; | |
1111 | mas->min = 0; | |
1112 | return 0; | |
1113 | } | |
1114 | ||
633769c9 LH |
1115 | if (!mas->min) |
1116 | set_min = true; | |
1117 | ||
1118 | if (mas->max == ULONG_MAX) | |
1119 | set_max = true; | |
1120 | ||
54a611b6 LH |
1121 | min = 0; |
1122 | max = ULONG_MAX; | |
1123 | do { | |
1124 | p_enode = a_enode; | |
afc754c6 | 1125 | a_type = mas_parent_type(mas, p_enode); |
54a611b6 LH |
1126 | a_node = mte_parent(p_enode); |
1127 | a_slot = mte_parent_slot(p_enode); | |
54a611b6 | 1128 | a_enode = mt_mk_node(a_node, a_type); |
39d0bd86 LH |
1129 | pivots = ma_pivots(a_node, a_type); |
1130 | ||
1131 | if (unlikely(ma_dead_node(a_node))) | |
1132 | return 1; | |
54a611b6 LH |
1133 | |
1134 | if (!set_min && a_slot) { | |
1135 | set_min = true; | |
1136 | min = pivots[a_slot - 1] + 1; | |
1137 | } | |
1138 | ||
1139 | if (!set_max && a_slot < mt_pivots[a_type]) { | |
1140 | set_max = true; | |
1141 | max = pivots[a_slot]; | |
1142 | } | |
1143 | ||
1144 | if (unlikely(ma_dead_node(a_node))) | |
1145 | return 1; | |
1146 | ||
1147 | if (unlikely(ma_is_root(a_node))) | |
1148 | break; | |
1149 | ||
1150 | } while (!set_min || !set_max); | |
1151 | ||
1152 | mas->max = max; | |
1153 | mas->min = min; | |
1154 | return 0; | |
1155 | } | |
1156 | ||
1157 | /* | |
1158 | * mas_pop_node() - Get a previously allocated maple node from the maple state. | |
1159 | * @mas: The maple state | |
1160 | * | |
1161 | * Return: A pointer to a maple node. | |
1162 | */ | |
1163 | static inline struct maple_node *mas_pop_node(struct ma_state *mas) | |
1164 | { | |
1165 | struct maple_alloc *ret, *node = mas->alloc; | |
1166 | unsigned long total = mas_allocated(mas); | |
541e06b7 | 1167 | unsigned int req = mas_alloc_req(mas); |
54a611b6 LH |
1168 | |
1169 | /* nothing or a request pending. */ | |
541e06b7 | 1170 | if (WARN_ON(!total)) |
54a611b6 LH |
1171 | return NULL; |
1172 | ||
1173 | if (total == 1) { | |
1174 | /* single allocation in this ma_state */ | |
1175 | mas->alloc = NULL; | |
1176 | ret = node; | |
1177 | goto single_node; | |
1178 | } | |
1179 | ||
541e06b7 | 1180 | if (node->node_count == 1) { |
54a611b6 LH |
1181 | /* Single allocation in this node. */ |
1182 | mas->alloc = node->slot[0]; | |
54a611b6 LH |
1183 | mas->alloc->total = node->total - 1; |
1184 | ret = node; | |
1185 | goto new_head; | |
1186 | } | |
54a611b6 | 1187 | node->total--; |
541e06b7 LH |
1188 | ret = node->slot[--node->node_count]; |
1189 | node->slot[node->node_count] = NULL; | |
54a611b6 LH |
1190 | |
1191 | single_node: | |
1192 | new_head: | |
541e06b7 LH |
1193 | if (req) { |
1194 | req++; | |
1195 | mas_set_alloc_req(mas, req); | |
54a611b6 | 1196 | } |
541e06b7 LH |
1197 | |
1198 | memset(ret, 0, sizeof(*ret)); | |
54a611b6 LH |
1199 | return (struct maple_node *)ret; |
1200 | } | |
1201 | ||
1202 | /* | |
1203 | * mas_push_node() - Push a node back on the maple state allocation. | |
1204 | * @mas: The maple state | |
1205 | * @used: The used maple node | |
1206 | * | |
1207 | * Stores the maple node back into @mas->alloc for reuse. Updates allocated and | |
1208 | * requested node count as necessary. | |
1209 | */ | |
1210 | static inline void mas_push_node(struct ma_state *mas, struct maple_node *used) | |
1211 | { | |
1212 | struct maple_alloc *reuse = (struct maple_alloc *)used; | |
1213 | struct maple_alloc *head = mas->alloc; | |
1214 | unsigned long count; | |
1215 | unsigned int requested = mas_alloc_req(mas); | |
1216 | ||
54a611b6 LH |
1217 | count = mas_allocated(mas); |
1218 | ||
541e06b7 LH |
1219 | reuse->request_count = 0; |
1220 | reuse->node_count = 0; | |
1221 | if (count && (head->node_count < MAPLE_ALLOC_SLOTS)) { | |
1222 | head->slot[head->node_count++] = reuse; | |
54a611b6 LH |
1223 | head->total++; |
1224 | goto done; | |
1225 | } | |
1226 | ||
1227 | reuse->total = 1; | |
1228 | if ((head) && !((unsigned long)head & 0x1)) { | |
54a611b6 | 1229 | reuse->slot[0] = head; |
541e06b7 | 1230 | reuse->node_count = 1; |
54a611b6 LH |
1231 | reuse->total += head->total; |
1232 | } | |
1233 | ||
1234 | mas->alloc = reuse; | |
1235 | done: | |
1236 | if (requested > 1) | |
1237 | mas_set_alloc_req(mas, requested - 1); | |
1238 | } | |
1239 | ||
1240 | /* | |
1241 | * mas_alloc_nodes() - Allocate nodes into a maple state | |
1242 | * @mas: The maple state | |
1243 | * @gfp: The GFP Flags | |
1244 | */ | |
1245 | static inline void mas_alloc_nodes(struct ma_state *mas, gfp_t gfp) | |
1246 | { | |
1247 | struct maple_alloc *node; | |
54a611b6 | 1248 | unsigned long allocated = mas_allocated(mas); |
54a611b6 LH |
1249 | unsigned int requested = mas_alloc_req(mas); |
1250 | unsigned int count; | |
1251 | void **slots = NULL; | |
1252 | unsigned int max_req = 0; | |
1253 | ||
1254 | if (!requested) | |
1255 | return; | |
1256 | ||
1257 | mas_set_alloc_req(mas, 0); | |
1258 | if (mas->mas_flags & MA_STATE_PREALLOC) { | |
1259 | if (allocated) | |
1260 | return; | |
1261 | WARN_ON(!allocated); | |
1262 | } | |
1263 | ||
541e06b7 | 1264 | if (!allocated || mas->alloc->node_count == MAPLE_ALLOC_SLOTS) { |
54a611b6 LH |
1265 | node = (struct maple_alloc *)mt_alloc_one(gfp); |
1266 | if (!node) | |
1267 | goto nomem_one; | |
1268 | ||
541e06b7 | 1269 | if (allocated) { |
54a611b6 | 1270 | node->slot[0] = mas->alloc; |
541e06b7 LH |
1271 | node->node_count = 1; |
1272 | } else { | |
1273 | node->node_count = 0; | |
1274 | } | |
54a611b6 | 1275 | |
54a611b6 | 1276 | mas->alloc = node; |
541e06b7 | 1277 | node->total = ++allocated; |
54a611b6 LH |
1278 | requested--; |
1279 | } | |
1280 | ||
1281 | node = mas->alloc; | |
541e06b7 | 1282 | node->request_count = 0; |
54a611b6 | 1283 | while (requested) { |
1f5f12ec PZ |
1284 | max_req = MAPLE_ALLOC_SLOTS - node->node_count; |
1285 | slots = (void **)&node->slot[node->node_count]; | |
54a611b6 LH |
1286 | max_req = min(requested, max_req); |
1287 | count = mt_alloc_bulk(gfp, max_req, slots); | |
1288 | if (!count) | |
1289 | goto nomem_bulk; | |
1290 | ||
1f5f12ec PZ |
1291 | if (node->node_count == 0) { |
1292 | node->slot[0]->node_count = 0; | |
1293 | node->slot[0]->request_count = 0; | |
1294 | } | |
1295 | ||
54a611b6 | 1296 | node->node_count += count; |
541e06b7 | 1297 | allocated += count; |
c61b3a2b | 1298 | node = node->slot[0]; |
54a611b6 LH |
1299 | requested -= count; |
1300 | } | |
541e06b7 | 1301 | mas->alloc->total = allocated; |
54a611b6 LH |
1302 | return; |
1303 | ||
1304 | nomem_bulk: | |
1305 | /* Clean up potential freed allocations on bulk failure */ | |
1306 | memset(slots, 0, max_req * sizeof(unsigned long)); | |
1307 | nomem_one: | |
1308 | mas_set_alloc_req(mas, requested); | |
1309 | if (mas->alloc && !(((unsigned long)mas->alloc & 0x1))) | |
541e06b7 | 1310 | mas->alloc->total = allocated; |
54a611b6 | 1311 | mas_set_err(mas, -ENOMEM); |
54a611b6 LH |
1312 | } |
1313 | ||
1314 | /* | |
1315 | * mas_free() - Free an encoded maple node | |
1316 | * @mas: The maple state | |
1317 | * @used: The encoded maple node to free. | |
1318 | * | |
1319 | * Uses rcu free if necessary, pushes @used back on the maple state allocations | |
1320 | * otherwise. | |
1321 | */ | |
1322 | static inline void mas_free(struct ma_state *mas, struct maple_enode *used) | |
1323 | { | |
1324 | struct maple_node *tmp = mte_to_node(used); | |
1325 | ||
1326 | if (mt_in_rcu(mas->tree)) | |
1327 | ma_free_rcu(tmp); | |
1328 | else | |
1329 | mas_push_node(mas, tmp); | |
1330 | } | |
1331 | ||
1332 | /* | |
1333 | * mas_node_count() - Check if enough nodes are allocated and request more if | |
1334 | * there is not enough nodes. | |
1335 | * @mas: The maple state | |
1336 | * @count: The number of nodes needed | |
1337 | * @gfp: the gfp flags | |
1338 | */ | |
1339 | static void mas_node_count_gfp(struct ma_state *mas, int count, gfp_t gfp) | |
1340 | { | |
1341 | unsigned long allocated = mas_allocated(mas); | |
1342 | ||
1343 | if (allocated < count) { | |
1344 | mas_set_alloc_req(mas, count - allocated); | |
1345 | mas_alloc_nodes(mas, gfp); | |
1346 | } | |
1347 | } | |
1348 | ||
1349 | /* | |
1350 | * mas_node_count() - Check if enough nodes are allocated and request more if | |
1351 | * there is not enough nodes. | |
1352 | * @mas: The maple state | |
1353 | * @count: The number of nodes needed | |
1354 | * | |
1355 | * Note: Uses GFP_NOWAIT | __GFP_NOWARN for gfp flags. | |
1356 | */ | |
1357 | static void mas_node_count(struct ma_state *mas, int count) | |
1358 | { | |
1359 | return mas_node_count_gfp(mas, count, GFP_NOWAIT | __GFP_NOWARN); | |
1360 | } | |
1361 | ||
1362 | /* | |
1363 | * mas_start() - Sets up maple state for operations. | |
1364 | * @mas: The maple state. | |
1365 | * | |
46b34584 | 1366 | * If mas->node == MAS_START, then set the min, max and depth to |
54a611b6 LH |
1367 | * defaults. |
1368 | * | |
1369 | * Return: | |
1370 | * - If mas->node is an error or not MAS_START, return NULL. | |
1371 | * - If it's an empty tree: NULL & mas->node == MAS_NONE | |
1372 | * - If it's a single entry: The entry & mas->node == MAS_ROOT | |
1373 | * - If it's a tree: NULL & mas->node == safe root node. | |
1374 | */ | |
1375 | static inline struct maple_enode *mas_start(struct ma_state *mas) | |
1376 | { | |
1377 | if (likely(mas_is_start(mas))) { | |
1378 | struct maple_enode *root; | |
1379 | ||
54a611b6 LH |
1380 | mas->min = 0; |
1381 | mas->max = ULONG_MAX; | |
54a611b6 | 1382 | |
a7b92d59 | 1383 | retry: |
d0411860 | 1384 | mas->depth = 0; |
54a611b6 LH |
1385 | root = mas_root(mas); |
1386 | /* Tree with nodes */ | |
1387 | if (likely(xa_is_node(root))) { | |
9bbba563 | 1388 | mas->depth = 1; |
54a611b6 | 1389 | mas->node = mte_safe_root(root); |
46b34584 | 1390 | mas->offset = 0; |
a7b92d59 LH |
1391 | if (mte_dead_node(mas->node)) |
1392 | goto retry; | |
1393 | ||
54a611b6 LH |
1394 | return NULL; |
1395 | } | |
1396 | ||
1397 | /* empty tree */ | |
1398 | if (unlikely(!root)) { | |
46b34584 | 1399 | mas->node = MAS_NONE; |
54a611b6 LH |
1400 | mas->offset = MAPLE_NODE_SLOTS; |
1401 | return NULL; | |
1402 | } | |
1403 | ||
1404 | /* Single entry tree */ | |
1405 | mas->node = MAS_ROOT; | |
1406 | mas->offset = MAPLE_NODE_SLOTS; | |
1407 | ||
1408 | /* Single entry tree. */ | |
1409 | if (mas->index > 0) | |
1410 | return NULL; | |
1411 | ||
1412 | return root; | |
1413 | } | |
1414 | ||
1415 | return NULL; | |
1416 | } | |
1417 | ||
1418 | /* | |
1419 | * ma_data_end() - Find the end of the data in a node. | |
1420 | * @node: The maple node | |
1421 | * @type: The maple node type | |
1422 | * @pivots: The array of pivots in the node | |
1423 | * @max: The maximum value in the node | |
1424 | * | |
1425 | * Uses metadata to find the end of the data when possible. | |
1426 | * Return: The zero indexed last slot with data (may be null). | |
1427 | */ | |
1428 | static inline unsigned char ma_data_end(struct maple_node *node, | |
1429 | enum maple_type type, | |
1430 | unsigned long *pivots, | |
1431 | unsigned long max) | |
1432 | { | |
1433 | unsigned char offset; | |
1434 | ||
39d0bd86 LH |
1435 | if (!pivots) |
1436 | return 0; | |
1437 | ||
54a611b6 LH |
1438 | if (type == maple_arange_64) |
1439 | return ma_meta_end(node, type); | |
1440 | ||
1441 | offset = mt_pivots[type] - 1; | |
1442 | if (likely(!pivots[offset])) | |
1443 | return ma_meta_end(node, type); | |
1444 | ||
1445 | if (likely(pivots[offset] == max)) | |
1446 | return offset; | |
1447 | ||
1448 | return mt_pivots[type]; | |
1449 | } | |
1450 | ||
1451 | /* | |
1452 | * mas_data_end() - Find the end of the data (slot). | |
1453 | * @mas: the maple state | |
1454 | * | |
1455 | * This method is optimized to check the metadata of a node if the node type | |
1456 | * supports data end metadata. | |
1457 | * | |
1458 | * Return: The zero indexed last slot with data (may be null). | |
1459 | */ | |
1460 | static inline unsigned char mas_data_end(struct ma_state *mas) | |
1461 | { | |
1462 | enum maple_type type; | |
1463 | struct maple_node *node; | |
1464 | unsigned char offset; | |
1465 | unsigned long *pivots; | |
1466 | ||
1467 | type = mte_node_type(mas->node); | |
1468 | node = mas_mn(mas); | |
1469 | if (type == maple_arange_64) | |
1470 | return ma_meta_end(node, type); | |
1471 | ||
1472 | pivots = ma_pivots(node, type); | |
39d0bd86 LH |
1473 | if (unlikely(ma_dead_node(node))) |
1474 | return 0; | |
1475 | ||
54a611b6 LH |
1476 | offset = mt_pivots[type] - 1; |
1477 | if (likely(!pivots[offset])) | |
1478 | return ma_meta_end(node, type); | |
1479 | ||
1480 | if (likely(pivots[offset] == mas->max)) | |
1481 | return offset; | |
1482 | ||
1483 | return mt_pivots[type]; | |
1484 | } | |
1485 | ||
1486 | /* | |
1487 | * mas_leaf_max_gap() - Returns the largest gap in a leaf node | |
1488 | * @mas - the maple state | |
1489 | * | |
1490 | * Return: The maximum gap in the leaf. | |
1491 | */ | |
1492 | static unsigned long mas_leaf_max_gap(struct ma_state *mas) | |
1493 | { | |
1494 | enum maple_type mt; | |
1495 | unsigned long pstart, gap, max_gap; | |
1496 | struct maple_node *mn; | |
1497 | unsigned long *pivots; | |
1498 | void __rcu **slots; | |
1499 | unsigned char i; | |
1500 | unsigned char max_piv; | |
1501 | ||
1502 | mt = mte_node_type(mas->node); | |
1503 | mn = mas_mn(mas); | |
1504 | slots = ma_slots(mn, mt); | |
1505 | max_gap = 0; | |
1506 | if (unlikely(ma_is_dense(mt))) { | |
1507 | gap = 0; | |
1508 | for (i = 0; i < mt_slots[mt]; i++) { | |
1509 | if (slots[i]) { | |
1510 | if (gap > max_gap) | |
1511 | max_gap = gap; | |
1512 | gap = 0; | |
1513 | } else { | |
1514 | gap++; | |
1515 | } | |
1516 | } | |
1517 | if (gap > max_gap) | |
1518 | max_gap = gap; | |
1519 | return max_gap; | |
1520 | } | |
1521 | ||
1522 | /* | |
1523 | * Check the first implied pivot optimizes the loop below and slot 1 may | |
1524 | * be skipped if there is a gap in slot 0. | |
1525 | */ | |
1526 | pivots = ma_pivots(mn, mt); | |
1527 | if (likely(!slots[0])) { | |
1528 | max_gap = pivots[0] - mas->min + 1; | |
1529 | i = 2; | |
1530 | } else { | |
1531 | i = 1; | |
1532 | } | |
1533 | ||
1534 | /* reduce max_piv as the special case is checked before the loop */ | |
1535 | max_piv = ma_data_end(mn, mt, pivots, mas->max) - 1; | |
1536 | /* | |
1537 | * Check end implied pivot which can only be a gap on the right most | |
1538 | * node. | |
1539 | */ | |
1540 | if (unlikely(mas->max == ULONG_MAX) && !slots[max_piv + 1]) { | |
1541 | gap = ULONG_MAX - pivots[max_piv]; | |
1542 | if (gap > max_gap) | |
1543 | max_gap = gap; | |
1544 | } | |
1545 | ||
1546 | for (; i <= max_piv; i++) { | |
1547 | /* data == no gap. */ | |
1548 | if (likely(slots[i])) | |
1549 | continue; | |
1550 | ||
1551 | pstart = pivots[i - 1]; | |
1552 | gap = pivots[i] - pstart; | |
1553 | if (gap > max_gap) | |
1554 | max_gap = gap; | |
1555 | ||
1556 | /* There cannot be two gaps in a row. */ | |
1557 | i++; | |
1558 | } | |
1559 | return max_gap; | |
1560 | } | |
1561 | ||
1562 | /* | |
1563 | * ma_max_gap() - Get the maximum gap in a maple node (non-leaf) | |
1564 | * @node: The maple node | |
1565 | * @gaps: The pointer to the gaps | |
1566 | * @mt: The maple node type | |
1567 | * @*off: Pointer to store the offset location of the gap. | |
1568 | * | |
1569 | * Uses the metadata data end to scan backwards across set gaps. | |
1570 | * | |
1571 | * Return: The maximum gap value | |
1572 | */ | |
1573 | static inline unsigned long | |
1574 | ma_max_gap(struct maple_node *node, unsigned long *gaps, enum maple_type mt, | |
1575 | unsigned char *off) | |
1576 | { | |
1577 | unsigned char offset, i; | |
1578 | unsigned long max_gap = 0; | |
1579 | ||
1580 | i = offset = ma_meta_end(node, mt); | |
1581 | do { | |
1582 | if (gaps[i] > max_gap) { | |
1583 | max_gap = gaps[i]; | |
1584 | offset = i; | |
1585 | } | |
1586 | } while (i--); | |
1587 | ||
1588 | *off = offset; | |
1589 | return max_gap; | |
1590 | } | |
1591 | ||
1592 | /* | |
1593 | * mas_max_gap() - find the largest gap in a non-leaf node and set the slot. | |
1594 | * @mas: The maple state. | |
1595 | * | |
54a611b6 LH |
1596 | * Return: The gap value. |
1597 | */ | |
1598 | static inline unsigned long mas_max_gap(struct ma_state *mas) | |
1599 | { | |
1600 | unsigned long *gaps; | |
1601 | unsigned char offset; | |
1602 | enum maple_type mt; | |
1603 | struct maple_node *node; | |
1604 | ||
1605 | mt = mte_node_type(mas->node); | |
1606 | if (ma_is_leaf(mt)) | |
1607 | return mas_leaf_max_gap(mas); | |
1608 | ||
1609 | node = mas_mn(mas); | |
bec1b51e | 1610 | MAS_BUG_ON(mas, mt != maple_arange_64); |
54a611b6 | 1611 | offset = ma_meta_gap(node, mt); |
54a611b6 LH |
1612 | gaps = ma_gaps(node, mt); |
1613 | return gaps[offset]; | |
1614 | } | |
1615 | ||
1616 | /* | |
1617 | * mas_parent_gap() - Set the parent gap and any gaps above, as needed | |
1618 | * @mas: The maple state | |
1619 | * @offset: The gap offset in the parent to set | |
1620 | * @new: The new gap value. | |
1621 | * | |
1622 | * Set the parent gap then continue to set the gap upwards, using the metadata | |
1623 | * of the parent to see if it is necessary to check the node above. | |
1624 | */ | |
1625 | static inline void mas_parent_gap(struct ma_state *mas, unsigned char offset, | |
1626 | unsigned long new) | |
1627 | { | |
1628 | unsigned long meta_gap = 0; | |
1629 | struct maple_node *pnode; | |
1630 | struct maple_enode *penode; | |
1631 | unsigned long *pgaps; | |
1632 | unsigned char meta_offset; | |
1633 | enum maple_type pmt; | |
1634 | ||
1635 | pnode = mte_parent(mas->node); | |
afc754c6 | 1636 | pmt = mas_parent_type(mas, mas->node); |
54a611b6 LH |
1637 | penode = mt_mk_node(pnode, pmt); |
1638 | pgaps = ma_gaps(pnode, pmt); | |
1639 | ||
1640 | ascend: | |
bec1b51e | 1641 | MAS_BUG_ON(mas, pmt != maple_arange_64); |
54a611b6 | 1642 | meta_offset = ma_meta_gap(pnode, pmt); |
d695c30a | 1643 | meta_gap = pgaps[meta_offset]; |
54a611b6 LH |
1644 | |
1645 | pgaps[offset] = new; | |
1646 | ||
1647 | if (meta_gap == new) | |
1648 | return; | |
1649 | ||
1650 | if (offset != meta_offset) { | |
1651 | if (meta_gap > new) | |
1652 | return; | |
1653 | ||
1654 | ma_set_meta_gap(pnode, pmt, offset); | |
1655 | } else if (new < meta_gap) { | |
54a611b6 LH |
1656 | new = ma_max_gap(pnode, pgaps, pmt, &meta_offset); |
1657 | ma_set_meta_gap(pnode, pmt, meta_offset); | |
1658 | } | |
1659 | ||
1660 | if (ma_is_root(pnode)) | |
1661 | return; | |
1662 | ||
1663 | /* Go to the parent node. */ | |
1664 | pnode = mte_parent(penode); | |
afc754c6 | 1665 | pmt = mas_parent_type(mas, penode); |
54a611b6 LH |
1666 | pgaps = ma_gaps(pnode, pmt); |
1667 | offset = mte_parent_slot(penode); | |
1668 | penode = mt_mk_node(pnode, pmt); | |
1669 | goto ascend; | |
1670 | } | |
1671 | ||
1672 | /* | |
1673 | * mas_update_gap() - Update a nodes gaps and propagate up if necessary. | |
1674 | * @mas - the maple state. | |
1675 | */ | |
1676 | static inline void mas_update_gap(struct ma_state *mas) | |
1677 | { | |
1678 | unsigned char pslot; | |
1679 | unsigned long p_gap; | |
1680 | unsigned long max_gap; | |
1681 | ||
1682 | if (!mt_is_alloc(mas->tree)) | |
1683 | return; | |
1684 | ||
1685 | if (mte_is_root(mas->node)) | |
1686 | return; | |
1687 | ||
1688 | max_gap = mas_max_gap(mas); | |
1689 | ||
1690 | pslot = mte_parent_slot(mas->node); | |
1691 | p_gap = ma_gaps(mte_parent(mas->node), | |
afc754c6 | 1692 | mas_parent_type(mas, mas->node))[pslot]; |
54a611b6 LH |
1693 | |
1694 | if (p_gap != max_gap) | |
1695 | mas_parent_gap(mas, pslot, max_gap); | |
1696 | } | |
1697 | ||
1698 | /* | |
1699 | * mas_adopt_children() - Set the parent pointer of all nodes in @parent to | |
1700 | * @parent with the slot encoded. | |
1701 | * @mas - the maple state (for the tree) | |
1702 | * @parent - the maple encoded node containing the children. | |
1703 | */ | |
1704 | static inline void mas_adopt_children(struct ma_state *mas, | |
1705 | struct maple_enode *parent) | |
1706 | { | |
1707 | enum maple_type type = mte_node_type(parent); | |
068bafca | 1708 | struct maple_node *node = mte_to_node(parent); |
54a611b6 LH |
1709 | void __rcu **slots = ma_slots(node, type); |
1710 | unsigned long *pivots = ma_pivots(node, type); | |
1711 | struct maple_enode *child; | |
1712 | unsigned char offset; | |
1713 | ||
1714 | offset = ma_data_end(node, type, pivots, mas->max); | |
1715 | do { | |
1716 | child = mas_slot_locked(mas, slots, offset); | |
bf96715e | 1717 | mas_set_parent(mas, child, parent, offset); |
54a611b6 LH |
1718 | } while (offset--); |
1719 | } | |
1720 | ||
1721 | /* | |
1238f6a2 LH |
1722 | * mas_put_in_tree() - Put a new node in the tree, smp_wmb(), and mark the old |
1723 | * node as dead. | |
1724 | * @mas - the maple state with the new node | |
1725 | * @old_enode - The old maple encoded node to replace. | |
54a611b6 | 1726 | */ |
1238f6a2 LH |
1727 | static inline void mas_put_in_tree(struct ma_state *mas, |
1728 | struct maple_enode *old_enode) | |
14c4b5ab | 1729 | __must_hold(mas->tree->ma_lock) |
54a611b6 | 1730 | { |
1238f6a2 LH |
1731 | unsigned char offset; |
1732 | void __rcu **slots; | |
54a611b6 LH |
1733 | |
1734 | if (mte_is_root(mas->node)) { | |
4ffc2ee2 | 1735 | mas_mn(mas)->parent = ma_parent_ptr(mas_tree_parent(mas)); |
54a611b6 LH |
1736 | rcu_assign_pointer(mas->tree->ma_root, mte_mk_root(mas->node)); |
1737 | mas_set_height(mas); | |
1738 | } else { | |
1238f6a2 LH |
1739 | |
1740 | offset = mte_parent_slot(mas->node); | |
1741 | slots = ma_slots(mte_parent(mas->node), | |
1742 | mas_parent_type(mas, mas->node)); | |
54a611b6 LH |
1743 | rcu_assign_pointer(slots[offset], mas->node); |
1744 | } | |
1745 | ||
1238f6a2 | 1746 | mte_set_node_dead(old_enode); |
54a611b6 LH |
1747 | } |
1748 | ||
72bcf4aa LH |
1749 | /* |
1750 | * mas_replace_node() - Replace a node by putting it in the tree, marking it | |
1751 | * dead, and freeing it. | |
1752 | * the parent encoding to locate the maple node in the tree. | |
1753 | * @mas - the ma_state with @mas->node pointing to the new node. | |
1754 | * @old_enode - The old maple encoded node. | |
1755 | */ | |
1756 | static inline void mas_replace_node(struct ma_state *mas, | |
1757 | struct maple_enode *old_enode) | |
1758 | __must_hold(mas->tree->ma_lock) | |
1759 | { | |
1238f6a2 | 1760 | mas_put_in_tree(mas, old_enode); |
72bcf4aa LH |
1761 | mas_free(mas, old_enode); |
1762 | } | |
1763 | ||
54a611b6 | 1764 | /* |
530f745c LH |
1765 | * mas_find_child() - Find a child who has the parent @mas->node. |
1766 | * @mas: the maple state with the parent. | |
54a611b6 LH |
1767 | * @child: the maple state to store the child. |
1768 | */ | |
530f745c | 1769 | static inline bool mas_find_child(struct ma_state *mas, struct ma_state *child) |
14c4b5ab | 1770 | __must_hold(mas->tree->ma_lock) |
54a611b6 LH |
1771 | { |
1772 | enum maple_type mt; | |
1773 | unsigned char offset; | |
1774 | unsigned char end; | |
1775 | unsigned long *pivots; | |
1776 | struct maple_enode *entry; | |
1777 | struct maple_node *node; | |
1778 | void __rcu **slots; | |
1779 | ||
1780 | mt = mte_node_type(mas->node); | |
1781 | node = mas_mn(mas); | |
1782 | slots = ma_slots(node, mt); | |
1783 | pivots = ma_pivots(node, mt); | |
1784 | end = ma_data_end(node, mt, pivots, mas->max); | |
1785 | for (offset = mas->offset; offset <= end; offset++) { | |
1786 | entry = mas_slot_locked(mas, slots, offset); | |
1787 | if (mte_parent(entry) == node) { | |
1788 | *child = *mas; | |
1789 | mas->offset = offset + 1; | |
1790 | child->offset = offset; | |
1791 | mas_descend(child); | |
1792 | child->offset = 0; | |
1793 | return true; | |
1794 | } | |
1795 | } | |
1796 | return false; | |
1797 | } | |
1798 | ||
1799 | /* | |
1800 | * mab_shift_right() - Shift the data in mab right. Note, does not clean out the | |
1801 | * old data or set b_node->b_end. | |
1802 | * @b_node: the maple_big_node | |
1803 | * @shift: the shift count | |
1804 | */ | |
1805 | static inline void mab_shift_right(struct maple_big_node *b_node, | |
1806 | unsigned char shift) | |
1807 | { | |
1808 | unsigned long size = b_node->b_end * sizeof(unsigned long); | |
1809 | ||
1810 | memmove(b_node->pivot + shift, b_node->pivot, size); | |
1811 | memmove(b_node->slot + shift, b_node->slot, size); | |
1812 | if (b_node->type == maple_arange_64) | |
1813 | memmove(b_node->gap + shift, b_node->gap, size); | |
1814 | } | |
1815 | ||
1816 | /* | |
1817 | * mab_middle_node() - Check if a middle node is needed (unlikely) | |
1818 | * @b_node: the maple_big_node that contains the data. | |
1819 | * @size: the amount of data in the b_node | |
1820 | * @split: the potential split location | |
1821 | * @slot_count: the size that can be stored in a single node being considered. | |
1822 | * | |
1823 | * Return: true if a middle node is required. | |
1824 | */ | |
1825 | static inline bool mab_middle_node(struct maple_big_node *b_node, int split, | |
1826 | unsigned char slot_count) | |
1827 | { | |
1828 | unsigned char size = b_node->b_end; | |
1829 | ||
1830 | if (size >= 2 * slot_count) | |
1831 | return true; | |
1832 | ||
1833 | if (!b_node->slot[split] && (size >= 2 * slot_count - 1)) | |
1834 | return true; | |
1835 | ||
1836 | return false; | |
1837 | } | |
1838 | ||
1839 | /* | |
1840 | * mab_no_null_split() - ensure the split doesn't fall on a NULL | |
1841 | * @b_node: the maple_big_node with the data | |
1842 | * @split: the suggested split location | |
1843 | * @slot_count: the number of slots in the node being considered. | |
1844 | * | |
1845 | * Return: the split location. | |
1846 | */ | |
1847 | static inline int mab_no_null_split(struct maple_big_node *b_node, | |
1848 | unsigned char split, unsigned char slot_count) | |
1849 | { | |
1850 | if (!b_node->slot[split]) { | |
1851 | /* | |
1852 | * If the split is less than the max slot && the right side will | |
1853 | * still be sufficient, then increment the split on NULL. | |
1854 | */ | |
1855 | if ((split < slot_count - 1) && | |
1856 | (b_node->b_end - split) > (mt_min_slots[b_node->type])) | |
1857 | split++; | |
1858 | else | |
1859 | split--; | |
1860 | } | |
1861 | return split; | |
1862 | } | |
1863 | ||
1864 | /* | |
1865 | * mab_calc_split() - Calculate the split location and if there needs to be two | |
1866 | * splits. | |
1867 | * @bn: The maple_big_node with the data | |
1868 | * @mid_split: The second split, if required. 0 otherwise. | |
1869 | * | |
1870 | * Return: The first split location. The middle split is set in @mid_split. | |
1871 | */ | |
1872 | static inline int mab_calc_split(struct ma_state *mas, | |
1873 | struct maple_big_node *bn, unsigned char *mid_split, unsigned long min) | |
1874 | { | |
1875 | unsigned char b_end = bn->b_end; | |
1876 | int split = b_end / 2; /* Assume equal split. */ | |
1877 | unsigned char slot_min, slot_count = mt_slots[bn->type]; | |
1878 | ||
1879 | /* | |
1880 | * To support gap tracking, all NULL entries are kept together and a node cannot | |
1881 | * end on a NULL entry, with the exception of the left-most leaf. The | |
1882 | * limitation means that the split of a node must be checked for this condition | |
1883 | * and be able to put more data in one direction or the other. | |
1884 | */ | |
1885 | if (unlikely((mas->mas_flags & MA_STATE_BULK))) { | |
1886 | *mid_split = 0; | |
1887 | split = b_end - mt_min_slots[bn->type]; | |
1888 | ||
1889 | if (!ma_is_leaf(bn->type)) | |
1890 | return split; | |
1891 | ||
1892 | mas->mas_flags |= MA_STATE_REBALANCE; | |
1893 | if (!bn->slot[split]) | |
1894 | split--; | |
1895 | return split; | |
1896 | } | |
1897 | ||
1898 | /* | |
1899 | * Although extremely rare, it is possible to enter what is known as the 3-way | |
1900 | * split scenario. The 3-way split comes about by means of a store of a range | |
1901 | * that overwrites the end and beginning of two full nodes. The result is a set | |
1902 | * of entries that cannot be stored in 2 nodes. Sometimes, these two nodes can | |
1903 | * also be located in different parent nodes which are also full. This can | |
1904 | * carry upwards all the way to the root in the worst case. | |
1905 | */ | |
1906 | if (unlikely(mab_middle_node(bn, split, slot_count))) { | |
1907 | split = b_end / 3; | |
1908 | *mid_split = split * 2; | |
1909 | } else { | |
1910 | slot_min = mt_min_slots[bn->type]; | |
1911 | ||
1912 | *mid_split = 0; | |
1913 | /* | |
1914 | * Avoid having a range less than the slot count unless it | |
1915 | * causes one node to be deficient. | |
1916 | * NOTE: mt_min_slots is 1 based, b_end and split are zero. | |
1917 | */ | |
5729e06c LH |
1918 | while ((split < slot_count - 1) && |
1919 | ((bn->pivot[split] - min) < slot_count - 1) && | |
1920 | (b_end - split > slot_min)) | |
54a611b6 LH |
1921 | split++; |
1922 | } | |
1923 | ||
1924 | /* Avoid ending a node on a NULL entry */ | |
1925 | split = mab_no_null_split(bn, split, slot_count); | |
54a611b6 | 1926 | |
e11cb683 VY |
1927 | if (unlikely(*mid_split)) |
1928 | *mid_split = mab_no_null_split(bn, *mid_split, slot_count); | |
54a611b6 LH |
1929 | |
1930 | return split; | |
1931 | } | |
1932 | ||
1933 | /* | |
1934 | * mas_mab_cp() - Copy data from a maple state inclusively to a maple_big_node | |
1935 | * and set @b_node->b_end to the next free slot. | |
1936 | * @mas: The maple state | |
1937 | * @mas_start: The starting slot to copy | |
1938 | * @mas_end: The end slot to copy (inclusively) | |
1939 | * @b_node: The maple_big_node to place the data | |
1940 | * @mab_start: The starting location in maple_big_node to store the data. | |
1941 | */ | |
1942 | static inline void mas_mab_cp(struct ma_state *mas, unsigned char mas_start, | |
1943 | unsigned char mas_end, struct maple_big_node *b_node, | |
1944 | unsigned char mab_start) | |
1945 | { | |
1946 | enum maple_type mt; | |
1947 | struct maple_node *node; | |
1948 | void __rcu **slots; | |
1949 | unsigned long *pivots, *gaps; | |
1950 | int i = mas_start, j = mab_start; | |
1951 | unsigned char piv_end; | |
1952 | ||
1953 | node = mas_mn(mas); | |
1954 | mt = mte_node_type(mas->node); | |
1955 | pivots = ma_pivots(node, mt); | |
1956 | if (!i) { | |
1957 | b_node->pivot[j] = pivots[i++]; | |
1958 | if (unlikely(i > mas_end)) | |
1959 | goto complete; | |
1960 | j++; | |
1961 | } | |
1962 | ||
1963 | piv_end = min(mas_end, mt_pivots[mt]); | |
1964 | for (; i < piv_end; i++, j++) { | |
1965 | b_node->pivot[j] = pivots[i]; | |
1966 | if (unlikely(!b_node->pivot[j])) | |
1967 | break; | |
1968 | ||
1969 | if (unlikely(mas->max == b_node->pivot[j])) | |
1970 | goto complete; | |
1971 | } | |
1972 | ||
1973 | if (likely(i <= mas_end)) | |
1974 | b_node->pivot[j] = mas_safe_pivot(mas, pivots, i, mt); | |
1975 | ||
1976 | complete: | |
1977 | b_node->b_end = ++j; | |
1978 | j -= mab_start; | |
1979 | slots = ma_slots(node, mt); | |
1980 | memcpy(b_node->slot + mab_start, slots + mas_start, sizeof(void *) * j); | |
1981 | if (!ma_is_leaf(mt) && mt_is_alloc(mas->tree)) { | |
1982 | gaps = ma_gaps(node, mt); | |
1983 | memcpy(b_node->gap + mab_start, gaps + mas_start, | |
1984 | sizeof(unsigned long) * j); | |
1985 | } | |
1986 | } | |
1987 | ||
1988 | /* | |
1989 | * mas_leaf_set_meta() - Set the metadata of a leaf if possible. | |
1990 | * @mas: The maple state | |
1991 | * @node: The maple node | |
1992 | * @pivots: pointer to the maple node pivots | |
1993 | * @mt: The maple type | |
1994 | * @end: The assumed end | |
1995 | * | |
1996 | * Note, end may be incremented within this function but not modified at the | |
1997 | * source. This is fine since the metadata is the last thing to be stored in a | |
1998 | * node during a write. | |
1999 | */ | |
2000 | static inline void mas_leaf_set_meta(struct ma_state *mas, | |
2001 | struct maple_node *node, unsigned long *pivots, | |
2002 | enum maple_type mt, unsigned char end) | |
2003 | { | |
2004 | /* There is no room for metadata already */ | |
2005 | if (mt_pivots[mt] <= end) | |
2006 | return; | |
2007 | ||
2008 | if (pivots[end] && pivots[end] < mas->max) | |
2009 | end++; | |
2010 | ||
2011 | if (end < mt_slots[mt] - 1) | |
2012 | ma_set_meta(node, mt, 0, end); | |
2013 | } | |
2014 | ||
2015 | /* | |
2016 | * mab_mas_cp() - Copy data from maple_big_node to a maple encoded node. | |
2017 | * @b_node: the maple_big_node that has the data | |
2018 | * @mab_start: the start location in @b_node. | |
2019 | * @mab_end: The end location in @b_node (inclusively) | |
2020 | * @mas: The maple state with the maple encoded node. | |
2021 | */ | |
2022 | static inline void mab_mas_cp(struct maple_big_node *b_node, | |
2023 | unsigned char mab_start, unsigned char mab_end, | |
2024 | struct ma_state *mas, bool new_max) | |
2025 | { | |
2026 | int i, j = 0; | |
2027 | enum maple_type mt = mte_node_type(mas->node); | |
2028 | struct maple_node *node = mte_to_node(mas->node); | |
2029 | void __rcu **slots = ma_slots(node, mt); | |
2030 | unsigned long *pivots = ma_pivots(node, mt); | |
2031 | unsigned long *gaps = NULL; | |
2032 | unsigned char end; | |
2033 | ||
2034 | if (mab_end - mab_start > mt_pivots[mt]) | |
2035 | mab_end--; | |
2036 | ||
2037 | if (!pivots[mt_pivots[mt] - 1]) | |
2038 | slots[mt_pivots[mt]] = NULL; | |
2039 | ||
2040 | i = mab_start; | |
2041 | do { | |
2042 | pivots[j++] = b_node->pivot[i++]; | |
2043 | } while (i <= mab_end && likely(b_node->pivot[i])); | |
2044 | ||
2045 | memcpy(slots, b_node->slot + mab_start, | |
2046 | sizeof(void *) * (i - mab_start)); | |
2047 | ||
2048 | if (new_max) | |
2049 | mas->max = b_node->pivot[i - 1]; | |
2050 | ||
2051 | end = j - 1; | |
2052 | if (likely(!ma_is_leaf(mt) && mt_is_alloc(mas->tree))) { | |
2053 | unsigned long max_gap = 0; | |
d695c30a | 2054 | unsigned char offset = 0; |
54a611b6 LH |
2055 | |
2056 | gaps = ma_gaps(node, mt); | |
2057 | do { | |
2058 | gaps[--j] = b_node->gap[--i]; | |
2059 | if (gaps[j] > max_gap) { | |
2060 | offset = j; | |
2061 | max_gap = gaps[j]; | |
2062 | } | |
2063 | } while (j); | |
2064 | ||
2065 | ma_set_meta(node, mt, offset, end); | |
2066 | } else { | |
2067 | mas_leaf_set_meta(mas, node, pivots, mt, end); | |
2068 | } | |
2069 | } | |
2070 | ||
54a611b6 LH |
2071 | /* |
2072 | * mas_bulk_rebalance() - Rebalance the end of a tree after a bulk insert. | |
2073 | * @mas: The maple state | |
2074 | * @end: The maple node end | |
2075 | * @mt: The maple node type | |
2076 | */ | |
2077 | static inline void mas_bulk_rebalance(struct ma_state *mas, unsigned char end, | |
2078 | enum maple_type mt) | |
2079 | { | |
2080 | if (!(mas->mas_flags & MA_STATE_BULK)) | |
2081 | return; | |
2082 | ||
2083 | if (mte_is_root(mas->node)) | |
2084 | return; | |
2085 | ||
2086 | if (end > mt_min_slots[mt]) { | |
2087 | mas->mas_flags &= ~MA_STATE_REBALANCE; | |
2088 | return; | |
2089 | } | |
2090 | } | |
2091 | ||
2092 | /* | |
2093 | * mas_store_b_node() - Store an @entry into the b_node while also copying the | |
2094 | * data from a maple encoded node. | |
2095 | * @wr_mas: the maple write state | |
2096 | * @b_node: the maple_big_node to fill with data | |
2097 | * @offset_end: the offset to end copying | |
2098 | * | |
2099 | * Return: The actual end of the data stored in @b_node | |
2100 | */ | |
44081c77 | 2101 | static noinline_for_kasan void mas_store_b_node(struct ma_wr_state *wr_mas, |
54a611b6 LH |
2102 | struct maple_big_node *b_node, unsigned char offset_end) |
2103 | { | |
2104 | unsigned char slot; | |
2105 | unsigned char b_end; | |
2106 | /* Possible underflow of piv will wrap back to 0 before use. */ | |
2107 | unsigned long piv; | |
2108 | struct ma_state *mas = wr_mas->mas; | |
2109 | ||
2110 | b_node->type = wr_mas->type; | |
2111 | b_end = 0; | |
2112 | slot = mas->offset; | |
2113 | if (slot) { | |
2114 | /* Copy start data up to insert. */ | |
2115 | mas_mab_cp(mas, 0, slot - 1, b_node, 0); | |
2116 | b_end = b_node->b_end; | |
2117 | piv = b_node->pivot[b_end - 1]; | |
2118 | } else | |
2119 | piv = mas->min - 1; | |
2120 | ||
2121 | if (piv + 1 < mas->index) { | |
2122 | /* Handle range starting after old range */ | |
2123 | b_node->slot[b_end] = wr_mas->content; | |
2124 | if (!wr_mas->content) | |
2125 | b_node->gap[b_end] = mas->index - 1 - piv; | |
2126 | b_node->pivot[b_end++] = mas->index - 1; | |
2127 | } | |
2128 | ||
2129 | /* Store the new entry. */ | |
2130 | mas->offset = b_end; | |
2131 | b_node->slot[b_end] = wr_mas->entry; | |
2132 | b_node->pivot[b_end] = mas->last; | |
2133 | ||
2134 | /* Appended. */ | |
2135 | if (mas->last >= mas->max) | |
2136 | goto b_end; | |
2137 | ||
2138 | /* Handle new range ending before old range ends */ | |
29b2681f | 2139 | piv = mas_safe_pivot(mas, wr_mas->pivots, offset_end, wr_mas->type); |
54a611b6 LH |
2140 | if (piv > mas->last) { |
2141 | if (piv == ULONG_MAX) | |
2142 | mas_bulk_rebalance(mas, b_node->b_end, wr_mas->type); | |
2143 | ||
2144 | if (offset_end != slot) | |
2145 | wr_mas->content = mas_slot_locked(mas, wr_mas->slots, | |
2146 | offset_end); | |
2147 | ||
2148 | b_node->slot[++b_end] = wr_mas->content; | |
2149 | if (!wr_mas->content) | |
2150 | b_node->gap[b_end] = piv - mas->last + 1; | |
2151 | b_node->pivot[b_end] = piv; | |
2152 | } | |
2153 | ||
2154 | slot = offset_end + 1; | |
2155 | if (slot > wr_mas->node_end) | |
2156 | goto b_end; | |
2157 | ||
2158 | /* Copy end data to the end of the node. */ | |
2159 | mas_mab_cp(mas, slot, wr_mas->node_end + 1, b_node, ++b_end); | |
2160 | b_node->b_end--; | |
2161 | return; | |
2162 | ||
2163 | b_end: | |
2164 | b_node->b_end = b_end; | |
2165 | } | |
2166 | ||
2167 | /* | |
2168 | * mas_prev_sibling() - Find the previous node with the same parent. | |
2169 | * @mas: the maple state | |
2170 | * | |
2171 | * Return: True if there is a previous sibling, false otherwise. | |
2172 | */ | |
2173 | static inline bool mas_prev_sibling(struct ma_state *mas) | |
2174 | { | |
2175 | unsigned int p_slot = mte_parent_slot(mas->node); | |
2176 | ||
2177 | if (mte_is_root(mas->node)) | |
2178 | return false; | |
2179 | ||
2180 | if (!p_slot) | |
2181 | return false; | |
2182 | ||
2183 | mas_ascend(mas); | |
2184 | mas->offset = p_slot - 1; | |
2185 | mas_descend(mas); | |
2186 | return true; | |
2187 | } | |
2188 | ||
2189 | /* | |
2190 | * mas_next_sibling() - Find the next node with the same parent. | |
2191 | * @mas: the maple state | |
2192 | * | |
2193 | * Return: true if there is a next sibling, false otherwise. | |
2194 | */ | |
2195 | static inline bool mas_next_sibling(struct ma_state *mas) | |
2196 | { | |
2197 | MA_STATE(parent, mas->tree, mas->index, mas->last); | |
2198 | ||
2199 | if (mte_is_root(mas->node)) | |
2200 | return false; | |
2201 | ||
2202 | parent = *mas; | |
2203 | mas_ascend(&parent); | |
2204 | parent.offset = mte_parent_slot(mas->node) + 1; | |
2205 | if (parent.offset > mas_data_end(&parent)) | |
2206 | return false; | |
2207 | ||
2208 | *mas = parent; | |
2209 | mas_descend(mas); | |
2210 | return true; | |
2211 | } | |
2212 | ||
2213 | /* | |
2214 | * mte_node_or_node() - Return the encoded node or MAS_NONE. | |
2215 | * @enode: The encoded maple node. | |
2216 | * | |
2217 | * Shorthand to avoid setting %NULLs in the tree or maple_subtree_state. | |
2218 | * | |
2219 | * Return: @enode or MAS_NONE | |
2220 | */ | |
2221 | static inline struct maple_enode *mte_node_or_none(struct maple_enode *enode) | |
2222 | { | |
2223 | if (enode) | |
2224 | return enode; | |
2225 | ||
2226 | return ma_enode_ptr(MAS_NONE); | |
2227 | } | |
2228 | ||
2229 | /* | |
2230 | * mas_wr_node_walk() - Find the correct offset for the index in the @mas. | |
2231 | * @wr_mas: The maple write state | |
2232 | * | |
2233 | * Uses mas_slot_locked() and does not need to worry about dead nodes. | |
2234 | */ | |
2235 | static inline void mas_wr_node_walk(struct ma_wr_state *wr_mas) | |
2236 | { | |
2237 | struct ma_state *mas = wr_mas->mas; | |
97f7e094 | 2238 | unsigned char count, offset; |
54a611b6 LH |
2239 | |
2240 | if (unlikely(ma_is_dense(wr_mas->type))) { | |
2241 | wr_mas->r_max = wr_mas->r_min = mas->index; | |
2242 | mas->offset = mas->index = mas->min; | |
2243 | return; | |
2244 | } | |
2245 | ||
2246 | wr_mas->node = mas_mn(wr_mas->mas); | |
2247 | wr_mas->pivots = ma_pivots(wr_mas->node, wr_mas->type); | |
2248 | count = wr_mas->node_end = ma_data_end(wr_mas->node, wr_mas->type, | |
2249 | wr_mas->pivots, mas->max); | |
2250 | offset = mas->offset; | |
54a611b6 | 2251 | |
97f7e094 PZ |
2252 | while (offset < count && mas->index > wr_mas->pivots[offset]) |
2253 | offset++; | |
54a611b6 | 2254 | |
97f7e094 PZ |
2255 | wr_mas->r_max = offset < count ? wr_mas->pivots[offset] : mas->max; |
2256 | wr_mas->r_min = mas_safe_min(mas, wr_mas->pivots, offset); | |
54a611b6 LH |
2257 | wr_mas->offset_end = mas->offset = offset; |
2258 | } | |
2259 | ||
54a611b6 LH |
2260 | /* |
2261 | * mast_rebalance_next() - Rebalance against the next node | |
2262 | * @mast: The maple subtree state | |
2263 | * @old_r: The encoded maple node to the right (next node). | |
2264 | */ | |
2265 | static inline void mast_rebalance_next(struct maple_subtree_state *mast) | |
2266 | { | |
2267 | unsigned char b_end = mast->bn->b_end; | |
2268 | ||
2269 | mas_mab_cp(mast->orig_r, 0, mt_slot_count(mast->orig_r->node), | |
2270 | mast->bn, b_end); | |
2271 | mast->orig_r->last = mast->orig_r->max; | |
2272 | } | |
2273 | ||
2274 | /* | |
2275 | * mast_rebalance_prev() - Rebalance against the previous node | |
2276 | * @mast: The maple subtree state | |
2277 | * @old_l: The encoded maple node to the left (previous node) | |
2278 | */ | |
2279 | static inline void mast_rebalance_prev(struct maple_subtree_state *mast) | |
2280 | { | |
2281 | unsigned char end = mas_data_end(mast->orig_l) + 1; | |
2282 | unsigned char b_end = mast->bn->b_end; | |
2283 | ||
2284 | mab_shift_right(mast->bn, end); | |
2285 | mas_mab_cp(mast->orig_l, 0, end - 1, mast->bn, 0); | |
2286 | mast->l->min = mast->orig_l->min; | |
2287 | mast->orig_l->index = mast->orig_l->min; | |
2288 | mast->bn->b_end = end + b_end; | |
2289 | mast->l->offset += end; | |
2290 | } | |
2291 | ||
2292 | /* | |
2293 | * mast_spanning_rebalance() - Rebalance nodes with nearest neighbour favouring | |
2294 | * the node to the right. Checking the nodes to the right then the left at each | |
530f745c | 2295 | * level upwards until root is reached. |
54a611b6 LH |
2296 | * Data is copied into the @mast->bn. |
2297 | * @mast: The maple_subtree_state. | |
2298 | */ | |
2299 | static inline | |
2300 | bool mast_spanning_rebalance(struct maple_subtree_state *mast) | |
2301 | { | |
2302 | struct ma_state r_tmp = *mast->orig_r; | |
2303 | struct ma_state l_tmp = *mast->orig_l; | |
54a611b6 LH |
2304 | unsigned char depth = 0; |
2305 | ||
2306 | r_tmp = *mast->orig_r; | |
2307 | l_tmp = *mast->orig_l; | |
2308 | do { | |
2309 | mas_ascend(mast->orig_r); | |
2310 | mas_ascend(mast->orig_l); | |
2311 | depth++; | |
54a611b6 | 2312 | if (mast->orig_r->offset < mas_data_end(mast->orig_r)) { |
54a611b6 LH |
2313 | mast->orig_r->offset++; |
2314 | do { | |
2315 | mas_descend(mast->orig_r); | |
2316 | mast->orig_r->offset = 0; | |
530f745c | 2317 | } while (--depth); |
54a611b6 LH |
2318 | |
2319 | mast_rebalance_next(mast); | |
54a611b6 LH |
2320 | *mast->orig_l = l_tmp; |
2321 | return true; | |
54a611b6 | 2322 | } else if (mast->orig_l->offset != 0) { |
54a611b6 LH |
2323 | mast->orig_l->offset--; |
2324 | do { | |
2325 | mas_descend(mast->orig_l); | |
2326 | mast->orig_l->offset = | |
2327 | mas_data_end(mast->orig_l); | |
530f745c | 2328 | } while (--depth); |
54a611b6 LH |
2329 | |
2330 | mast_rebalance_prev(mast); | |
54a611b6 LH |
2331 | *mast->orig_r = r_tmp; |
2332 | return true; | |
2333 | } | |
2334 | } while (!mte_is_root(mast->orig_r->node)); | |
2335 | ||
2336 | *mast->orig_r = r_tmp; | |
2337 | *mast->orig_l = l_tmp; | |
2338 | return false; | |
2339 | } | |
2340 | ||
2341 | /* | |
530f745c | 2342 | * mast_ascend() - Ascend the original left and right maple states. |
54a611b6 LH |
2343 | * @mast: the maple subtree state. |
2344 | * | |
530f745c LH |
2345 | * Ascend the original left and right sides. Set the offsets to point to the |
2346 | * data already in the new tree (@mast->l and @mast->r). | |
54a611b6 | 2347 | */ |
530f745c | 2348 | static inline void mast_ascend(struct maple_subtree_state *mast) |
54a611b6 LH |
2349 | { |
2350 | MA_WR_STATE(wr_mas, mast->orig_r, NULL); | |
54a611b6 LH |
2351 | mas_ascend(mast->orig_l); |
2352 | mas_ascend(mast->orig_r); | |
54a611b6 LH |
2353 | |
2354 | mast->orig_r->offset = 0; | |
2355 | mast->orig_r->index = mast->r->max; | |
2356 | /* last should be larger than or equal to index */ | |
2357 | if (mast->orig_r->last < mast->orig_r->index) | |
2358 | mast->orig_r->last = mast->orig_r->index; | |
530f745c | 2359 | |
54a611b6 LH |
2360 | wr_mas.type = mte_node_type(mast->orig_r->node); |
2361 | mas_wr_node_walk(&wr_mas); | |
2362 | /* Set up the left side of things */ | |
2363 | mast->orig_l->offset = 0; | |
2364 | mast->orig_l->index = mast->l->min; | |
2365 | wr_mas.mas = mast->orig_l; | |
2366 | wr_mas.type = mte_node_type(mast->orig_l->node); | |
2367 | mas_wr_node_walk(&wr_mas); | |
2368 | ||
2369 | mast->bn->type = wr_mas.type; | |
2370 | } | |
2371 | ||
2372 | /* | |
2373 | * mas_new_ma_node() - Create and return a new maple node. Helper function. | |
2374 | * @mas: the maple state with the allocations. | |
2375 | * @b_node: the maple_big_node with the type encoding. | |
2376 | * | |
2377 | * Use the node type from the maple_big_node to allocate a new node from the | |
2378 | * ma_state. This function exists mainly for code readability. | |
2379 | * | |
2380 | * Return: A new maple encoded node | |
2381 | */ | |
2382 | static inline struct maple_enode | |
2383 | *mas_new_ma_node(struct ma_state *mas, struct maple_big_node *b_node) | |
2384 | { | |
2385 | return mt_mk_node(ma_mnode_ptr(mas_pop_node(mas)), b_node->type); | |
2386 | } | |
2387 | ||
2388 | /* | |
2389 | * mas_mab_to_node() - Set up right and middle nodes | |
2390 | * | |
2391 | * @mas: the maple state that contains the allocations. | |
2392 | * @b_node: the node which contains the data. | |
2393 | * @left: The pointer which will have the left node | |
2394 | * @right: The pointer which may have the right node | |
2395 | * @middle: the pointer which may have the middle node (rare) | |
2396 | * @mid_split: the split location for the middle node | |
2397 | * | |
2398 | * Return: the split of left. | |
2399 | */ | |
2400 | static inline unsigned char mas_mab_to_node(struct ma_state *mas, | |
2401 | struct maple_big_node *b_node, struct maple_enode **left, | |
2402 | struct maple_enode **right, struct maple_enode **middle, | |
2403 | unsigned char *mid_split, unsigned long min) | |
2404 | { | |
2405 | unsigned char split = 0; | |
2406 | unsigned char slot_count = mt_slots[b_node->type]; | |
2407 | ||
2408 | *left = mas_new_ma_node(mas, b_node); | |
2409 | *right = NULL; | |
2410 | *middle = NULL; | |
2411 | *mid_split = 0; | |
2412 | ||
2413 | if (b_node->b_end < slot_count) { | |
2414 | split = b_node->b_end; | |
2415 | } else { | |
2416 | split = mab_calc_split(mas, b_node, mid_split, min); | |
2417 | *right = mas_new_ma_node(mas, b_node); | |
2418 | } | |
2419 | ||
2420 | if (*mid_split) | |
2421 | *middle = mas_new_ma_node(mas, b_node); | |
2422 | ||
2423 | return split; | |
2424 | ||
2425 | } | |
2426 | ||
2427 | /* | |
2428 | * mab_set_b_end() - Add entry to b_node at b_node->b_end and increment the end | |
2429 | * pointer. | |
2430 | * @b_node - the big node to add the entry | |
2431 | * @mas - the maple state to get the pivot (mas->max) | |
2432 | * @entry - the entry to add, if NULL nothing happens. | |
2433 | */ | |
2434 | static inline void mab_set_b_end(struct maple_big_node *b_node, | |
2435 | struct ma_state *mas, | |
2436 | void *entry) | |
2437 | { | |
2438 | if (!entry) | |
2439 | return; | |
2440 | ||
2441 | b_node->slot[b_node->b_end] = entry; | |
2442 | if (mt_is_alloc(mas->tree)) | |
2443 | b_node->gap[b_node->b_end] = mas_max_gap(mas); | |
2444 | b_node->pivot[b_node->b_end++] = mas->max; | |
2445 | } | |
2446 | ||
2447 | /* | |
2448 | * mas_set_split_parent() - combine_then_separate helper function. Sets the parent | |
2449 | * of @mas->node to either @left or @right, depending on @slot and @split | |
2450 | * | |
2451 | * @mas - the maple state with the node that needs a parent | |
2452 | * @left - possible parent 1 | |
2453 | * @right - possible parent 2 | |
2454 | * @slot - the slot the mas->node was placed | |
2455 | * @split - the split location between @left and @right | |
2456 | */ | |
2457 | static inline void mas_set_split_parent(struct ma_state *mas, | |
2458 | struct maple_enode *left, | |
2459 | struct maple_enode *right, | |
2460 | unsigned char *slot, unsigned char split) | |
2461 | { | |
2462 | if (mas_is_none(mas)) | |
2463 | return; | |
2464 | ||
2465 | if ((*slot) <= split) | |
bf96715e | 2466 | mas_set_parent(mas, mas->node, left, *slot); |
54a611b6 | 2467 | else if (right) |
bf96715e | 2468 | mas_set_parent(mas, mas->node, right, (*slot) - split - 1); |
54a611b6 LH |
2469 | |
2470 | (*slot)++; | |
2471 | } | |
2472 | ||
2473 | /* | |
2474 | * mte_mid_split_check() - Check if the next node passes the mid-split | |
2475 | * @**l: Pointer to left encoded maple node. | |
2476 | * @**m: Pointer to middle encoded maple node. | |
2477 | * @**r: Pointer to right encoded maple node. | |
2478 | * @slot: The offset | |
2479 | * @*split: The split location. | |
2480 | * @mid_split: The middle split. | |
2481 | */ | |
2482 | static inline void mte_mid_split_check(struct maple_enode **l, | |
2483 | struct maple_enode **r, | |
2484 | struct maple_enode *right, | |
2485 | unsigned char slot, | |
2486 | unsigned char *split, | |
2487 | unsigned char mid_split) | |
2488 | { | |
2489 | if (*r == right) | |
2490 | return; | |
2491 | ||
2492 | if (slot < mid_split) | |
2493 | return; | |
2494 | ||
2495 | *l = *r; | |
2496 | *r = right; | |
2497 | *split = mid_split; | |
2498 | } | |
2499 | ||
2500 | /* | |
2501 | * mast_set_split_parents() - Helper function to set three nodes parents. Slot | |
2502 | * is taken from @mast->l. | |
2503 | * @mast - the maple subtree state | |
2504 | * @left - the left node | |
2505 | * @right - the right node | |
2506 | * @split - the split location. | |
2507 | */ | |
2508 | static inline void mast_set_split_parents(struct maple_subtree_state *mast, | |
2509 | struct maple_enode *left, | |
2510 | struct maple_enode *middle, | |
2511 | struct maple_enode *right, | |
2512 | unsigned char split, | |
2513 | unsigned char mid_split) | |
2514 | { | |
2515 | unsigned char slot; | |
2516 | struct maple_enode *l = left; | |
2517 | struct maple_enode *r = right; | |
2518 | ||
2519 | if (mas_is_none(mast->l)) | |
2520 | return; | |
2521 | ||
2522 | if (middle) | |
2523 | r = middle; | |
2524 | ||
2525 | slot = mast->l->offset; | |
2526 | ||
2527 | mte_mid_split_check(&l, &r, right, slot, &split, mid_split); | |
2528 | mas_set_split_parent(mast->l, l, r, &slot, split); | |
2529 | ||
2530 | mte_mid_split_check(&l, &r, right, slot, &split, mid_split); | |
2531 | mas_set_split_parent(mast->m, l, r, &slot, split); | |
2532 | ||
2533 | mte_mid_split_check(&l, &r, right, slot, &split, mid_split); | |
2534 | mas_set_split_parent(mast->r, l, r, &slot, split); | |
2535 | } | |
2536 | ||
2537 | /* | |
530f745c LH |
2538 | * mas_topiary_node() - Dispose of a singe node |
2539 | * @mas: The maple state for pushing nodes | |
2540 | * @enode: The encoded maple node | |
2541 | * @in_rcu: If the tree is in rcu mode | |
54a611b6 | 2542 | * |
530f745c | 2543 | * The node will either be RCU freed or pushed back on the maple state. |
54a611b6 | 2544 | */ |
530f745c LH |
2545 | static inline void mas_topiary_node(struct ma_state *mas, |
2546 | struct maple_enode *enode, bool in_rcu) | |
54a611b6 | 2547 | { |
530f745c | 2548 | struct maple_node *tmp; |
1238f6a2 | 2549 | |
530f745c LH |
2550 | if (enode == MAS_NONE) |
2551 | return; | |
1238f6a2 | 2552 | |
530f745c LH |
2553 | tmp = mte_to_node(enode); |
2554 | mte_set_node_dead(enode); | |
2555 | if (in_rcu) | |
2556 | ma_free_rcu(tmp); | |
2557 | else | |
2558 | mas_push_node(mas, tmp); | |
2559 | } | |
54a611b6 | 2560 | |
530f745c LH |
2561 | /* |
2562 | * mas_topiary_replace() - Replace the data with new data, then repair the | |
2563 | * parent links within the new tree. Iterate over the dead sub-tree and collect | |
2564 | * the dead subtrees and topiary the nodes that are no longer of use. | |
2565 | * | |
2566 | * The new tree will have up to three children with the correct parent. Keep | |
2567 | * track of the new entries as they need to be followed to find the next level | |
2568 | * of new entries. | |
2569 | * | |
2570 | * The old tree will have up to three children with the old parent. Keep track | |
2571 | * of the old entries as they may have more nodes below replaced. Nodes within | |
2572 | * [index, last] are dead subtrees, others need to be freed and followed. | |
2573 | * | |
2574 | * @mas: The maple state pointing at the new data | |
2575 | * @old_enode: The maple encoded node being replaced | |
2576 | * | |
2577 | */ | |
2578 | static inline void mas_topiary_replace(struct ma_state *mas, | |
2579 | struct maple_enode *old_enode) | |
2580 | { | |
2581 | struct ma_state tmp[3], tmp_next[3]; | |
2582 | MA_TOPIARY(subtrees, mas->tree); | |
2583 | bool in_rcu; | |
2584 | int i, n; | |
2585 | ||
2586 | /* Place data in tree & then mark node as old */ | |
1238f6a2 | 2587 | mas_put_in_tree(mas, old_enode); |
54a611b6 | 2588 | |
530f745c LH |
2589 | /* Update the parent pointers in the tree */ |
2590 | tmp[0] = *mas; | |
2591 | tmp[0].offset = 0; | |
2592 | tmp[1].node = MAS_NONE; | |
2593 | tmp[2].node = MAS_NONE; | |
2594 | while (!mte_is_leaf(tmp[0].node)) { | |
2595 | n = 0; | |
2596 | for (i = 0; i < 3; i++) { | |
2597 | if (mas_is_none(&tmp[i])) | |
2598 | continue; | |
54a611b6 | 2599 | |
530f745c LH |
2600 | while (n < 3) { |
2601 | if (!mas_find_child(&tmp[i], &tmp_next[n])) | |
2602 | break; | |
2603 | n++; | |
2604 | } | |
54a611b6 | 2605 | |
530f745c LH |
2606 | mas_adopt_children(&tmp[i], tmp[i].node); |
2607 | } | |
54a611b6 | 2608 | |
530f745c LH |
2609 | if (MAS_WARN_ON(mas, n == 0)) |
2610 | break; | |
54a611b6 | 2611 | |
530f745c LH |
2612 | while (n < 3) |
2613 | tmp_next[n++].node = MAS_NONE; | |
2614 | ||
2615 | for (i = 0; i < 3; i++) | |
2616 | tmp[i] = tmp_next[i]; | |
2617 | } | |
2618 | ||
2619 | /* Collect the old nodes that need to be discarded */ | |
2620 | if (mte_is_leaf(old_enode)) | |
2621 | return mas_free(mas, old_enode); | |
2622 | ||
2623 | tmp[0] = *mas; | |
2624 | tmp[0].offset = 0; | |
2625 | tmp[0].node = old_enode; | |
2626 | tmp[1].node = MAS_NONE; | |
2627 | tmp[2].node = MAS_NONE; | |
2628 | in_rcu = mt_in_rcu(mas->tree); | |
2629 | do { | |
2630 | n = 0; | |
2631 | for (i = 0; i < 3; i++) { | |
2632 | if (mas_is_none(&tmp[i])) | |
2633 | continue; | |
2634 | ||
2635 | while (n < 3) { | |
2636 | if (!mas_find_child(&tmp[i], &tmp_next[n])) | |
2637 | break; | |
2638 | ||
2639 | if ((tmp_next[n].min >= tmp_next->index) && | |
2640 | (tmp_next[n].max <= tmp_next->last)) { | |
2641 | mat_add(&subtrees, tmp_next[n].node); | |
2642 | tmp_next[n].node = MAS_NONE; | |
2643 | } else { | |
2644 | n++; | |
2645 | } | |
2646 | } | |
2647 | } | |
2648 | ||
2649 | if (MAS_WARN_ON(mas, n == 0)) | |
2650 | break; | |
2651 | ||
2652 | while (n < 3) | |
2653 | tmp_next[n++].node = MAS_NONE; | |
2654 | ||
2655 | for (i = 0; i < 3; i++) { | |
2656 | mas_topiary_node(mas, tmp[i].node, in_rcu); | |
2657 | tmp[i] = tmp_next[i]; | |
2658 | } | |
2659 | } while (!mte_is_leaf(tmp[0].node)); | |
2660 | ||
2661 | for (i = 0; i < 3; i++) | |
2662 | mas_topiary_node(mas, tmp[i].node, in_rcu); | |
2663 | ||
2664 | mas_mat_destroy(mas, &subtrees); | |
54a611b6 LH |
2665 | } |
2666 | ||
2667 | /* | |
530f745c | 2668 | * mas_wmb_replace() - Write memory barrier and replace |
54a611b6 | 2669 | * @mas: The maple state |
530f745c LH |
2670 | * @old: The old maple encoded node that is being replaced. |
2671 | * | |
2672 | * Updates gap as necessary. | |
54a611b6 | 2673 | */ |
530f745c LH |
2674 | static inline void mas_wmb_replace(struct ma_state *mas, |
2675 | struct maple_enode *old_enode) | |
54a611b6 | 2676 | { |
530f745c LH |
2677 | /* Insert the new data in the tree */ |
2678 | mas_topiary_replace(mas, old_enode); | |
2679 | ||
2680 | if (mte_is_leaf(mas->node)) | |
2681 | return; | |
2682 | ||
2683 | mas_update_gap(mas); | |
54a611b6 LH |
2684 | } |
2685 | ||
2686 | /* | |
2687 | * mast_cp_to_nodes() - Copy data out to nodes. | |
2688 | * @mast: The maple subtree state | |
2689 | * @left: The left encoded maple node | |
2690 | * @middle: The middle encoded maple node | |
2691 | * @right: The right encoded maple node | |
2692 | * @split: The location to split between left and (middle ? middle : right) | |
2693 | * @mid_split: The location to split between middle and right. | |
2694 | */ | |
2695 | static inline void mast_cp_to_nodes(struct maple_subtree_state *mast, | |
2696 | struct maple_enode *left, struct maple_enode *middle, | |
2697 | struct maple_enode *right, unsigned char split, unsigned char mid_split) | |
2698 | { | |
2699 | bool new_lmax = true; | |
2700 | ||
2701 | mast->l->node = mte_node_or_none(left); | |
2702 | mast->m->node = mte_node_or_none(middle); | |
2703 | mast->r->node = mte_node_or_none(right); | |
2704 | ||
2705 | mast->l->min = mast->orig_l->min; | |
2706 | if (split == mast->bn->b_end) { | |
2707 | mast->l->max = mast->orig_r->max; | |
2708 | new_lmax = false; | |
2709 | } | |
2710 | ||
2711 | mab_mas_cp(mast->bn, 0, split, mast->l, new_lmax); | |
2712 | ||
2713 | if (middle) { | |
2714 | mab_mas_cp(mast->bn, 1 + split, mid_split, mast->m, true); | |
2715 | mast->m->min = mast->bn->pivot[split] + 1; | |
2716 | split = mid_split; | |
2717 | } | |
2718 | ||
2719 | mast->r->max = mast->orig_r->max; | |
2720 | if (right) { | |
2721 | mab_mas_cp(mast->bn, 1 + split, mast->bn->b_end, mast->r, false); | |
2722 | mast->r->min = mast->bn->pivot[split] + 1; | |
2723 | } | |
2724 | } | |
2725 | ||
2726 | /* | |
2727 | * mast_combine_cp_left - Copy in the original left side of the tree into the | |
2728 | * combined data set in the maple subtree state big node. | |
2729 | * @mast: The maple subtree state | |
2730 | */ | |
2731 | static inline void mast_combine_cp_left(struct maple_subtree_state *mast) | |
2732 | { | |
2733 | unsigned char l_slot = mast->orig_l->offset; | |
2734 | ||
2735 | if (!l_slot) | |
2736 | return; | |
2737 | ||
2738 | mas_mab_cp(mast->orig_l, 0, l_slot - 1, mast->bn, 0); | |
2739 | } | |
2740 | ||
2741 | /* | |
2742 | * mast_combine_cp_right: Copy in the original right side of the tree into the | |
2743 | * combined data set in the maple subtree state big node. | |
2744 | * @mast: The maple subtree state | |
2745 | */ | |
2746 | static inline void mast_combine_cp_right(struct maple_subtree_state *mast) | |
2747 | { | |
2748 | if (mast->bn->pivot[mast->bn->b_end - 1] >= mast->orig_r->max) | |
2749 | return; | |
2750 | ||
2751 | mas_mab_cp(mast->orig_r, mast->orig_r->offset + 1, | |
2752 | mt_slot_count(mast->orig_r->node), mast->bn, | |
2753 | mast->bn->b_end); | |
2754 | mast->orig_r->last = mast->orig_r->max; | |
2755 | } | |
2756 | ||
2757 | /* | |
2758 | * mast_sufficient: Check if the maple subtree state has enough data in the big | |
2759 | * node to create at least one sufficient node | |
2760 | * @mast: the maple subtree state | |
2761 | */ | |
2762 | static inline bool mast_sufficient(struct maple_subtree_state *mast) | |
2763 | { | |
2764 | if (mast->bn->b_end > mt_min_slot_count(mast->orig_l->node)) | |
2765 | return true; | |
2766 | ||
2767 | return false; | |
2768 | } | |
2769 | ||
2770 | /* | |
2771 | * mast_overflow: Check if there is too much data in the subtree state for a | |
2772 | * single node. | |
2773 | * @mast: The maple subtree state | |
2774 | */ | |
2775 | static inline bool mast_overflow(struct maple_subtree_state *mast) | |
2776 | { | |
2777 | if (mast->bn->b_end >= mt_slot_count(mast->orig_l->node)) | |
2778 | return true; | |
2779 | ||
2780 | return false; | |
2781 | } | |
2782 | ||
2783 | static inline void *mtree_range_walk(struct ma_state *mas) | |
2784 | { | |
2785 | unsigned long *pivots; | |
2786 | unsigned char offset; | |
2787 | struct maple_node *node; | |
2788 | struct maple_enode *next, *last; | |
2789 | enum maple_type type; | |
2790 | void __rcu **slots; | |
2791 | unsigned char end; | |
2792 | unsigned long max, min; | |
2793 | unsigned long prev_max, prev_min; | |
2794 | ||
1b9c9183 LB |
2795 | next = mas->node; |
2796 | min = mas->min; | |
54a611b6 LH |
2797 | max = mas->max; |
2798 | do { | |
2799 | offset = 0; | |
2800 | last = next; | |
2801 | node = mte_to_node(next); | |
2802 | type = mte_node_type(next); | |
2803 | pivots = ma_pivots(node, type); | |
2804 | end = ma_data_end(node, type, pivots, max); | |
2805 | if (unlikely(ma_dead_node(node))) | |
2806 | goto dead_node; | |
2807 | ||
2808 | if (pivots[offset] >= mas->index) { | |
2809 | prev_max = max; | |
2810 | prev_min = min; | |
2811 | max = pivots[offset]; | |
2812 | goto next; | |
2813 | } | |
2814 | ||
2815 | do { | |
2816 | offset++; | |
2817 | } while ((offset < end) && (pivots[offset] < mas->index)); | |
2818 | ||
2819 | prev_min = min; | |
2820 | min = pivots[offset - 1] + 1; | |
2821 | prev_max = max; | |
2822 | if (likely(offset < end && pivots[offset])) | |
2823 | max = pivots[offset]; | |
2824 | ||
2825 | next: | |
2826 | slots = ma_slots(node, type); | |
2827 | next = mt_slot(mas->tree, slots, offset); | |
2828 | if (unlikely(ma_dead_node(node))) | |
2829 | goto dead_node; | |
2830 | } while (!ma_is_leaf(type)); | |
2831 | ||
2832 | mas->offset = offset; | |
2833 | mas->index = min; | |
2834 | mas->last = max; | |
2835 | mas->min = prev_min; | |
2836 | mas->max = prev_max; | |
2837 | mas->node = last; | |
831978e3 | 2838 | return (void *)next; |
54a611b6 LH |
2839 | |
2840 | dead_node: | |
2841 | mas_reset(mas); | |
2842 | return NULL; | |
2843 | } | |
2844 | ||
2845 | /* | |
2846 | * mas_spanning_rebalance() - Rebalance across two nodes which may not be peers. | |
2847 | * @mas: The starting maple state | |
2848 | * @mast: The maple_subtree_state, keeps track of 4 maple states. | |
2849 | * @count: The estimated count of iterations needed. | |
2850 | * | |
2851 | * Follow the tree upwards from @l_mas and @r_mas for @count, or until the root | |
2852 | * is hit. First @b_node is split into two entries which are inserted into the | |
2853 | * next iteration of the loop. @b_node is returned populated with the final | |
2854 | * iteration. @mas is used to obtain allocations. orig_l_mas keeps track of the | |
2855 | * nodes that will remain active by using orig_l_mas->index and orig_l_mas->last | |
2856 | * to account of what has been copied into the new sub-tree. The update of | |
2857 | * orig_l_mas->last is used in mas_consume to find the slots that will need to | |
2858 | * be either freed or destroyed. orig_l_mas->depth keeps track of the height of | |
2859 | * the new sub-tree in case the sub-tree becomes the full tree. | |
2860 | * | |
2861 | * Return: the number of elements in b_node during the last loop. | |
2862 | */ | |
2863 | static int mas_spanning_rebalance(struct ma_state *mas, | |
2864 | struct maple_subtree_state *mast, unsigned char count) | |
2865 | { | |
2866 | unsigned char split, mid_split; | |
2867 | unsigned char slot = 0; | |
2868 | struct maple_enode *left = NULL, *middle = NULL, *right = NULL; | |
530f745c | 2869 | struct maple_enode *old_enode; |
54a611b6 LH |
2870 | |
2871 | MA_STATE(l_mas, mas->tree, mas->index, mas->index); | |
2872 | MA_STATE(r_mas, mas->tree, mas->index, mas->last); | |
2873 | MA_STATE(m_mas, mas->tree, mas->index, mas->index); | |
54a611b6 LH |
2874 | |
2875 | /* | |
2876 | * The tree needs to be rebalanced and leaves need to be kept at the same level. | |
2877 | * Rebalancing is done by use of the ``struct maple_topiary``. | |
2878 | */ | |
2879 | mast->l = &l_mas; | |
2880 | mast->m = &m_mas; | |
2881 | mast->r = &r_mas; | |
54a611b6 | 2882 | l_mas.node = r_mas.node = m_mas.node = MAS_NONE; |
0abb964a LH |
2883 | |
2884 | /* Check if this is not root and has sufficient data. */ | |
2885 | if (((mast->orig_l->min != 0) || (mast->orig_r->max != ULONG_MAX)) && | |
54a611b6 LH |
2886 | unlikely(mast->bn->b_end <= mt_min_slots[mast->bn->type])) |
2887 | mast_spanning_rebalance(mast); | |
2888 | ||
530f745c | 2889 | l_mas.depth = 0; |
54a611b6 LH |
2890 | |
2891 | /* | |
2892 | * Each level of the tree is examined and balanced, pushing data to the left or | |
2893 | * right, or rebalancing against left or right nodes is employed to avoid | |
2894 | * rippling up the tree to limit the amount of churn. Once a new sub-section of | |
2895 | * the tree is created, there may be a mix of new and old nodes. The old nodes | |
2896 | * will have the incorrect parent pointers and currently be in two trees: the | |
2897 | * original tree and the partially new tree. To remedy the parent pointers in | |
2898 | * the old tree, the new data is swapped into the active tree and a walk down | |
2899 | * the tree is performed and the parent pointers are updated. | |
530f745c | 2900 | * See mas_topiary_replace() for more information. |
54a611b6 LH |
2901 | */ |
2902 | while (count--) { | |
2903 | mast->bn->b_end--; | |
2904 | mast->bn->type = mte_node_type(mast->orig_l->node); | |
2905 | split = mas_mab_to_node(mas, mast->bn, &left, &right, &middle, | |
2906 | &mid_split, mast->orig_l->min); | |
2907 | mast_set_split_parents(mast, left, middle, right, split, | |
2908 | mid_split); | |
2909 | mast_cp_to_nodes(mast, left, middle, right, split, mid_split); | |
2910 | ||
2911 | /* | |
2912 | * Copy data from next level in the tree to mast->bn from next | |
2913 | * iteration | |
2914 | */ | |
2915 | memset(mast->bn, 0, sizeof(struct maple_big_node)); | |
2916 | mast->bn->type = mte_node_type(left); | |
530f745c | 2917 | l_mas.depth++; |
54a611b6 LH |
2918 | |
2919 | /* Root already stored in l->node. */ | |
2920 | if (mas_is_root_limits(mast->l)) | |
2921 | goto new_root; | |
2922 | ||
530f745c | 2923 | mast_ascend(mast); |
54a611b6 LH |
2924 | mast_combine_cp_left(mast); |
2925 | l_mas.offset = mast->bn->b_end; | |
2926 | mab_set_b_end(mast->bn, &l_mas, left); | |
2927 | mab_set_b_end(mast->bn, &m_mas, middle); | |
2928 | mab_set_b_end(mast->bn, &r_mas, right); | |
2929 | ||
2930 | /* Copy anything necessary out of the right node. */ | |
2931 | mast_combine_cp_right(mast); | |
54a611b6 LH |
2932 | mast->orig_l->last = mast->orig_l->max; |
2933 | ||
2934 | if (mast_sufficient(mast)) | |
2935 | continue; | |
2936 | ||
2937 | if (mast_overflow(mast)) | |
2938 | continue; | |
2939 | ||
2940 | /* May be a new root stored in mast->bn */ | |
2941 | if (mas_is_root_limits(mast->orig_l)) | |
2942 | break; | |
2943 | ||
2944 | mast_spanning_rebalance(mast); | |
2945 | ||
2946 | /* rebalancing from other nodes may require another loop. */ | |
2947 | if (!count) | |
2948 | count++; | |
2949 | } | |
2950 | ||
2951 | l_mas.node = mt_mk_node(ma_mnode_ptr(mas_pop_node(mas)), | |
2952 | mte_node_type(mast->orig_l->node)); | |
530f745c | 2953 | l_mas.depth++; |
54a611b6 | 2954 | mab_mas_cp(mast->bn, 0, mt_slots[mast->bn->type] - 1, &l_mas, true); |
bf96715e | 2955 | mas_set_parent(mas, left, l_mas.node, slot); |
54a611b6 | 2956 | if (middle) |
bf96715e | 2957 | mas_set_parent(mas, middle, l_mas.node, ++slot); |
54a611b6 LH |
2958 | |
2959 | if (right) | |
bf96715e | 2960 | mas_set_parent(mas, right, l_mas.node, ++slot); |
54a611b6 LH |
2961 | |
2962 | if (mas_is_root_limits(mast->l)) { | |
2963 | new_root: | |
530f745c LH |
2964 | mas_mn(mast->l)->parent = ma_parent_ptr(mas_tree_parent(mas)); |
2965 | while (!mte_is_root(mast->orig_l->node)) | |
2966 | mast_ascend(mast); | |
54a611b6 LH |
2967 | } else { |
2968 | mas_mn(&l_mas)->parent = mas_mn(mast->orig_l)->parent; | |
2969 | } | |
2970 | ||
530f745c LH |
2971 | old_enode = mast->orig_l->node; |
2972 | mas->depth = l_mas.depth; | |
2973 | mas->node = l_mas.node; | |
2974 | mas->min = l_mas.min; | |
2975 | mas->max = l_mas.max; | |
2976 | mas->offset = l_mas.offset; | |
2977 | mas_wmb_replace(mas, old_enode); | |
54a611b6 LH |
2978 | mtree_range_walk(mas); |
2979 | return mast->bn->b_end; | |
2980 | } | |
2981 | ||
2982 | /* | |
2983 | * mas_rebalance() - Rebalance a given node. | |
2984 | * @mas: The maple state | |
2985 | * @b_node: The big maple node. | |
2986 | * | |
2987 | * Rebalance two nodes into a single node or two new nodes that are sufficient. | |
2988 | * Continue upwards until tree is sufficient. | |
2989 | * | |
2990 | * Return: the number of elements in b_node during the last loop. | |
2991 | */ | |
2992 | static inline int mas_rebalance(struct ma_state *mas, | |
2993 | struct maple_big_node *b_node) | |
2994 | { | |
2995 | char empty_count = mas_mt_height(mas); | |
2996 | struct maple_subtree_state mast; | |
2997 | unsigned char shift, b_end = ++b_node->b_end; | |
2998 | ||
2999 | MA_STATE(l_mas, mas->tree, mas->index, mas->last); | |
3000 | MA_STATE(r_mas, mas->tree, mas->index, mas->last); | |
3001 | ||
3002 | trace_ma_op(__func__, mas); | |
3003 | ||
3004 | /* | |
3005 | * Rebalancing occurs if a node is insufficient. Data is rebalanced | |
3006 | * against the node to the right if it exists, otherwise the node to the | |
3007 | * left of this node is rebalanced against this node. If rebalancing | |
3008 | * causes just one node to be produced instead of two, then the parent | |
3009 | * is also examined and rebalanced if it is insufficient. Every level | |
3010 | * tries to combine the data in the same way. If one node contains the | |
3011 | * entire range of the tree, then that node is used as a new root node. | |
3012 | */ | |
c108df76 | 3013 | mas_node_count(mas, empty_count * 2 - 1); |
54a611b6 LH |
3014 | if (mas_is_err(mas)) |
3015 | return 0; | |
3016 | ||
3017 | mast.orig_l = &l_mas; | |
3018 | mast.orig_r = &r_mas; | |
3019 | mast.bn = b_node; | |
3020 | mast.bn->type = mte_node_type(mas->node); | |
3021 | ||
3022 | l_mas = r_mas = *mas; | |
3023 | ||
3024 | if (mas_next_sibling(&r_mas)) { | |
3025 | mas_mab_cp(&r_mas, 0, mt_slot_count(r_mas.node), b_node, b_end); | |
3026 | r_mas.last = r_mas.index = r_mas.max; | |
3027 | } else { | |
3028 | mas_prev_sibling(&l_mas); | |
3029 | shift = mas_data_end(&l_mas) + 1; | |
3030 | mab_shift_right(b_node, shift); | |
3031 | mas->offset += shift; | |
3032 | mas_mab_cp(&l_mas, 0, shift - 1, b_node, 0); | |
3033 | b_node->b_end = shift + b_end; | |
3034 | l_mas.index = l_mas.last = l_mas.min; | |
3035 | } | |
3036 | ||
3037 | return mas_spanning_rebalance(mas, &mast, empty_count); | |
3038 | } | |
3039 | ||
3040 | /* | |
3041 | * mas_destroy_rebalance() - Rebalance left-most node while destroying the maple | |
3042 | * state. | |
3043 | * @mas: The maple state | |
3044 | * @end: The end of the left-most node. | |
3045 | * | |
3046 | * During a mass-insert event (such as forking), it may be necessary to | |
3047 | * rebalance the left-most node when it is not sufficient. | |
3048 | */ | |
3049 | static inline void mas_destroy_rebalance(struct ma_state *mas, unsigned char end) | |
3050 | { | |
3051 | enum maple_type mt = mte_node_type(mas->node); | |
3052 | struct maple_node reuse, *newnode, *parent, *new_left, *left, *node; | |
72bcf4aa | 3053 | struct maple_enode *eparent, *old_eparent; |
54a611b6 LH |
3054 | unsigned char offset, tmp, split = mt_slots[mt] / 2; |
3055 | void __rcu **l_slots, **slots; | |
3056 | unsigned long *l_pivs, *pivs, gap; | |
3057 | bool in_rcu = mt_in_rcu(mas->tree); | |
3058 | ||
3059 | MA_STATE(l_mas, mas->tree, mas->index, mas->last); | |
3060 | ||
3061 | l_mas = *mas; | |
3062 | mas_prev_sibling(&l_mas); | |
3063 | ||
3064 | /* set up node. */ | |
3065 | if (in_rcu) { | |
3066 | /* Allocate for both left and right as well as parent. */ | |
3067 | mas_node_count(mas, 3); | |
3068 | if (mas_is_err(mas)) | |
3069 | return; | |
3070 | ||
3071 | newnode = mas_pop_node(mas); | |
3072 | } else { | |
3073 | newnode = &reuse; | |
3074 | } | |
3075 | ||
3076 | node = mas_mn(mas); | |
3077 | newnode->parent = node->parent; | |
3078 | slots = ma_slots(newnode, mt); | |
3079 | pivs = ma_pivots(newnode, mt); | |
3080 | left = mas_mn(&l_mas); | |
3081 | l_slots = ma_slots(left, mt); | |
3082 | l_pivs = ma_pivots(left, mt); | |
3083 | if (!l_slots[split]) | |
3084 | split++; | |
3085 | tmp = mas_data_end(&l_mas) - split; | |
3086 | ||
3087 | memcpy(slots, l_slots + split + 1, sizeof(void *) * tmp); | |
3088 | memcpy(pivs, l_pivs + split + 1, sizeof(unsigned long) * tmp); | |
3089 | pivs[tmp] = l_mas.max; | |
3090 | memcpy(slots + tmp, ma_slots(node, mt), sizeof(void *) * end); | |
3091 | memcpy(pivs + tmp, ma_pivots(node, mt), sizeof(unsigned long) * end); | |
3092 | ||
3093 | l_mas.max = l_pivs[split]; | |
3094 | mas->min = l_mas.max + 1; | |
72bcf4aa | 3095 | old_eparent = mt_mk_node(mte_parent(l_mas.node), |
afc754c6 | 3096 | mas_parent_type(&l_mas, l_mas.node)); |
54a611b6 LH |
3097 | tmp += end; |
3098 | if (!in_rcu) { | |
3099 | unsigned char max_p = mt_pivots[mt]; | |
3100 | unsigned char max_s = mt_slots[mt]; | |
3101 | ||
3102 | if (tmp < max_p) | |
3103 | memset(pivs + tmp, 0, | |
fb20e99a | 3104 | sizeof(unsigned long) * (max_p - tmp)); |
54a611b6 LH |
3105 | |
3106 | if (tmp < mt_slots[mt]) | |
3107 | memset(slots + tmp, 0, sizeof(void *) * (max_s - tmp)); | |
3108 | ||
3109 | memcpy(node, newnode, sizeof(struct maple_node)); | |
3110 | ma_set_meta(node, mt, 0, tmp - 1); | |
72bcf4aa | 3111 | mte_set_pivot(old_eparent, mte_parent_slot(l_mas.node), |
54a611b6 LH |
3112 | l_pivs[split]); |
3113 | ||
3114 | /* Remove data from l_pivs. */ | |
3115 | tmp = split + 1; | |
3116 | memset(l_pivs + tmp, 0, sizeof(unsigned long) * (max_p - tmp)); | |
3117 | memset(l_slots + tmp, 0, sizeof(void *) * (max_s - tmp)); | |
3118 | ma_set_meta(left, mt, 0, split); | |
72bcf4aa | 3119 | eparent = old_eparent; |
54a611b6 LH |
3120 | |
3121 | goto done; | |
3122 | } | |
3123 | ||
3124 | /* RCU requires replacing both l_mas, mas, and parent. */ | |
3125 | mas->node = mt_mk_node(newnode, mt); | |
3126 | ma_set_meta(newnode, mt, 0, tmp); | |
3127 | ||
3128 | new_left = mas_pop_node(mas); | |
3129 | new_left->parent = left->parent; | |
3130 | mt = mte_node_type(l_mas.node); | |
3131 | slots = ma_slots(new_left, mt); | |
3132 | pivs = ma_pivots(new_left, mt); | |
3133 | memcpy(slots, l_slots, sizeof(void *) * split); | |
3134 | memcpy(pivs, l_pivs, sizeof(unsigned long) * split); | |
3135 | ma_set_meta(new_left, mt, 0, split); | |
3136 | l_mas.node = mt_mk_node(new_left, mt); | |
3137 | ||
3138 | /* replace parent. */ | |
3139 | offset = mte_parent_slot(mas->node); | |
afc754c6 | 3140 | mt = mas_parent_type(&l_mas, l_mas.node); |
54a611b6 LH |
3141 | parent = mas_pop_node(mas); |
3142 | slots = ma_slots(parent, mt); | |
3143 | pivs = ma_pivots(parent, mt); | |
72bcf4aa | 3144 | memcpy(parent, mte_to_node(old_eparent), sizeof(struct maple_node)); |
54a611b6 LH |
3145 | rcu_assign_pointer(slots[offset], mas->node); |
3146 | rcu_assign_pointer(slots[offset - 1], l_mas.node); | |
3147 | pivs[offset - 1] = l_mas.max; | |
3148 | eparent = mt_mk_node(parent, mt); | |
3149 | done: | |
3150 | gap = mas_leaf_max_gap(mas); | |
3151 | mte_set_gap(eparent, mte_parent_slot(mas->node), gap); | |
3152 | gap = mas_leaf_max_gap(&l_mas); | |
3153 | mte_set_gap(eparent, mte_parent_slot(l_mas.node), gap); | |
3154 | mas_ascend(mas); | |
3155 | ||
72bcf4aa LH |
3156 | if (in_rcu) { |
3157 | mas_replace_node(mas, old_eparent); | |
3158 | mas_adopt_children(mas, mas->node); | |
3159 | } | |
54a611b6 LH |
3160 | |
3161 | mas_update_gap(mas); | |
3162 | } | |
3163 | ||
3164 | /* | |
3165 | * mas_split_final_node() - Split the final node in a subtree operation. | |
3166 | * @mast: the maple subtree state | |
3167 | * @mas: The maple state | |
3168 | * @height: The height of the tree in case it's a new root. | |
3169 | */ | |
3170 | static inline bool mas_split_final_node(struct maple_subtree_state *mast, | |
3171 | struct ma_state *mas, int height) | |
3172 | { | |
3173 | struct maple_enode *ancestor; | |
3174 | ||
3175 | if (mte_is_root(mas->node)) { | |
3176 | if (mt_is_alloc(mas->tree)) | |
3177 | mast->bn->type = maple_arange_64; | |
3178 | else | |
3179 | mast->bn->type = maple_range_64; | |
3180 | mas->depth = height; | |
3181 | } | |
3182 | /* | |
3183 | * Only a single node is used here, could be root. | |
3184 | * The Big_node data should just fit in a single node. | |
3185 | */ | |
3186 | ancestor = mas_new_ma_node(mas, mast->bn); | |
bf96715e LH |
3187 | mas_set_parent(mas, mast->l->node, ancestor, mast->l->offset); |
3188 | mas_set_parent(mas, mast->r->node, ancestor, mast->r->offset); | |
54a611b6 LH |
3189 | mte_to_node(ancestor)->parent = mas_mn(mas)->parent; |
3190 | ||
3191 | mast->l->node = ancestor; | |
3192 | mab_mas_cp(mast->bn, 0, mt_slots[mast->bn->type] - 1, mast->l, true); | |
3193 | mas->offset = mast->bn->b_end - 1; | |
3194 | return true; | |
3195 | } | |
3196 | ||
3197 | /* | |
3198 | * mast_fill_bnode() - Copy data into the big node in the subtree state | |
3199 | * @mast: The maple subtree state | |
3200 | * @mas: the maple state | |
3201 | * @skip: The number of entries to skip for new nodes insertion. | |
3202 | */ | |
3203 | static inline void mast_fill_bnode(struct maple_subtree_state *mast, | |
3204 | struct ma_state *mas, | |
3205 | unsigned char skip) | |
3206 | { | |
3207 | bool cp = true; | |
54a611b6 LH |
3208 | unsigned char split; |
3209 | ||
3210 | memset(mast->bn->gap, 0, sizeof(unsigned long) * ARRAY_SIZE(mast->bn->gap)); | |
3211 | memset(mast->bn->slot, 0, sizeof(unsigned long) * ARRAY_SIZE(mast->bn->slot)); | |
3212 | memset(mast->bn->pivot, 0, sizeof(unsigned long) * ARRAY_SIZE(mast->bn->pivot)); | |
3213 | mast->bn->b_end = 0; | |
3214 | ||
3215 | if (mte_is_root(mas->node)) { | |
3216 | cp = false; | |
3217 | } else { | |
3218 | mas_ascend(mas); | |
54a611b6 LH |
3219 | mas->offset = mte_parent_slot(mas->node); |
3220 | } | |
3221 | ||
3222 | if (cp && mast->l->offset) | |
3223 | mas_mab_cp(mas, 0, mast->l->offset - 1, mast->bn, 0); | |
3224 | ||
3225 | split = mast->bn->b_end; | |
3226 | mab_set_b_end(mast->bn, mast->l, mast->l->node); | |
3227 | mast->r->offset = mast->bn->b_end; | |
3228 | mab_set_b_end(mast->bn, mast->r, mast->r->node); | |
3229 | if (mast->bn->pivot[mast->bn->b_end - 1] == mas->max) | |
3230 | cp = false; | |
3231 | ||
3232 | if (cp) | |
3233 | mas_mab_cp(mas, split + skip, mt_slot_count(mas->node) - 1, | |
3234 | mast->bn, mast->bn->b_end); | |
3235 | ||
3236 | mast->bn->b_end--; | |
3237 | mast->bn->type = mte_node_type(mas->node); | |
3238 | } | |
3239 | ||
3240 | /* | |
3241 | * mast_split_data() - Split the data in the subtree state big node into regular | |
3242 | * nodes. | |
3243 | * @mast: The maple subtree state | |
3244 | * @mas: The maple state | |
3245 | * @split: The location to split the big node | |
3246 | */ | |
3247 | static inline void mast_split_data(struct maple_subtree_state *mast, | |
3248 | struct ma_state *mas, unsigned char split) | |
3249 | { | |
3250 | unsigned char p_slot; | |
3251 | ||
3252 | mab_mas_cp(mast->bn, 0, split, mast->l, true); | |
3253 | mte_set_pivot(mast->r->node, 0, mast->r->max); | |
3254 | mab_mas_cp(mast->bn, split + 1, mast->bn->b_end, mast->r, false); | |
3255 | mast->l->offset = mte_parent_slot(mas->node); | |
3256 | mast->l->max = mast->bn->pivot[split]; | |
3257 | mast->r->min = mast->l->max + 1; | |
3258 | if (mte_is_leaf(mas->node)) | |
3259 | return; | |
3260 | ||
3261 | p_slot = mast->orig_l->offset; | |
3262 | mas_set_split_parent(mast->orig_l, mast->l->node, mast->r->node, | |
3263 | &p_slot, split); | |
3264 | mas_set_split_parent(mast->orig_r, mast->l->node, mast->r->node, | |
3265 | &p_slot, split); | |
3266 | } | |
3267 | ||
3268 | /* | |
3269 | * mas_push_data() - Instead of splitting a node, it is beneficial to push the | |
3270 | * data to the right or left node if there is room. | |
3271 | * @mas: The maple state | |
3272 | * @height: The current height of the maple state | |
3273 | * @mast: The maple subtree state | |
3274 | * @left: Push left or not. | |
3275 | * | |
3276 | * Keeping the height of the tree low means faster lookups. | |
3277 | * | |
3278 | * Return: True if pushed, false otherwise. | |
3279 | */ | |
3280 | static inline bool mas_push_data(struct ma_state *mas, int height, | |
3281 | struct maple_subtree_state *mast, bool left) | |
3282 | { | |
3283 | unsigned char slot_total = mast->bn->b_end; | |
3284 | unsigned char end, space, split; | |
3285 | ||
3286 | MA_STATE(tmp_mas, mas->tree, mas->index, mas->last); | |
3287 | tmp_mas = *mas; | |
3288 | tmp_mas.depth = mast->l->depth; | |
3289 | ||
3290 | if (left && !mas_prev_sibling(&tmp_mas)) | |
3291 | return false; | |
3292 | else if (!left && !mas_next_sibling(&tmp_mas)) | |
3293 | return false; | |
3294 | ||
3295 | end = mas_data_end(&tmp_mas); | |
3296 | slot_total += end; | |
3297 | space = 2 * mt_slot_count(mas->node) - 2; | |
3298 | /* -2 instead of -1 to ensure there isn't a triple split */ | |
3299 | if (ma_is_leaf(mast->bn->type)) | |
3300 | space--; | |
3301 | ||
3302 | if (mas->max == ULONG_MAX) | |
3303 | space--; | |
3304 | ||
3305 | if (slot_total >= space) | |
3306 | return false; | |
3307 | ||
3308 | /* Get the data; Fill mast->bn */ | |
3309 | mast->bn->b_end++; | |
3310 | if (left) { | |
3311 | mab_shift_right(mast->bn, end + 1); | |
3312 | mas_mab_cp(&tmp_mas, 0, end, mast->bn, 0); | |
3313 | mast->bn->b_end = slot_total + 1; | |
3314 | } else { | |
3315 | mas_mab_cp(&tmp_mas, 0, end, mast->bn, mast->bn->b_end); | |
3316 | } | |
3317 | ||
3318 | /* Configure mast for splitting of mast->bn */ | |
3319 | split = mt_slots[mast->bn->type] - 2; | |
3320 | if (left) { | |
3321 | /* Switch mas to prev node */ | |
54a611b6 LH |
3322 | *mas = tmp_mas; |
3323 | /* Start using mast->l for the left side. */ | |
3324 | tmp_mas.node = mast->l->node; | |
3325 | *mast->l = tmp_mas; | |
3326 | } else { | |
54a611b6 LH |
3327 | tmp_mas.node = mast->r->node; |
3328 | *mast->r = tmp_mas; | |
3329 | split = slot_total - split; | |
3330 | } | |
3331 | split = mab_no_null_split(mast->bn, split, mt_slots[mast->bn->type]); | |
3332 | /* Update parent slot for split calculation. */ | |
3333 | if (left) | |
3334 | mast->orig_l->offset += end + 1; | |
3335 | ||
3336 | mast_split_data(mast, mas, split); | |
3337 | mast_fill_bnode(mast, mas, 2); | |
3338 | mas_split_final_node(mast, mas, height + 1); | |
3339 | return true; | |
3340 | } | |
3341 | ||
3342 | /* | |
3343 | * mas_split() - Split data that is too big for one node into two. | |
3344 | * @mas: The maple state | |
3345 | * @b_node: The maple big node | |
3346 | * Return: 1 on success, 0 on failure. | |
3347 | */ | |
3348 | static int mas_split(struct ma_state *mas, struct maple_big_node *b_node) | |
3349 | { | |
54a611b6 LH |
3350 | struct maple_subtree_state mast; |
3351 | int height = 0; | |
3352 | unsigned char mid_split, split = 0; | |
530f745c | 3353 | struct maple_enode *old; |
54a611b6 LH |
3354 | |
3355 | /* | |
3356 | * Splitting is handled differently from any other B-tree; the Maple | |
3357 | * Tree splits upwards. Splitting up means that the split operation | |
3358 | * occurs when the walk of the tree hits the leaves and not on the way | |
3359 | * down. The reason for splitting up is that it is impossible to know | |
3360 | * how much space will be needed until the leaf is (or leaves are) | |
3361 | * reached. Since overwriting data is allowed and a range could | |
3362 | * overwrite more than one range or result in changing one entry into 3 | |
3363 | * entries, it is impossible to know if a split is required until the | |
3364 | * data is examined. | |
3365 | * | |
3366 | * Splitting is a balancing act between keeping allocations to a minimum | |
3367 | * and avoiding a 'jitter' event where a tree is expanded to make room | |
3368 | * for an entry followed by a contraction when the entry is removed. To | |
3369 | * accomplish the balance, there are empty slots remaining in both left | |
3370 | * and right nodes after a split. | |
3371 | */ | |
3372 | MA_STATE(l_mas, mas->tree, mas->index, mas->last); | |
3373 | MA_STATE(r_mas, mas->tree, mas->index, mas->last); | |
3374 | MA_STATE(prev_l_mas, mas->tree, mas->index, mas->last); | |
3375 | MA_STATE(prev_r_mas, mas->tree, mas->index, mas->last); | |
54a611b6 LH |
3376 | |
3377 | trace_ma_op(__func__, mas); | |
3378 | mas->depth = mas_mt_height(mas); | |
3379 | /* Allocation failures will happen early. */ | |
3380 | mas_node_count(mas, 1 + mas->depth * 2); | |
3381 | if (mas_is_err(mas)) | |
3382 | return 0; | |
3383 | ||
3384 | mast.l = &l_mas; | |
3385 | mast.r = &r_mas; | |
3386 | mast.orig_l = &prev_l_mas; | |
3387 | mast.orig_r = &prev_r_mas; | |
54a611b6 LH |
3388 | mast.bn = b_node; |
3389 | ||
3390 | while (height++ <= mas->depth) { | |
3391 | if (mt_slots[b_node->type] > b_node->b_end) { | |
3392 | mas_split_final_node(&mast, mas, height); | |
3393 | break; | |
3394 | } | |
3395 | ||
3396 | l_mas = r_mas = *mas; | |
3397 | l_mas.node = mas_new_ma_node(mas, b_node); | |
3398 | r_mas.node = mas_new_ma_node(mas, b_node); | |
3399 | /* | |
3400 | * Another way that 'jitter' is avoided is to terminate a split up early if the | |
3401 | * left or right node has space to spare. This is referred to as "pushing left" | |
3402 | * or "pushing right" and is similar to the B* tree, except the nodes left or | |
3403 | * right can rarely be reused due to RCU, but the ripple upwards is halted which | |
3404 | * is a significant savings. | |
3405 | */ | |
3406 | /* Try to push left. */ | |
3407 | if (mas_push_data(mas, height, &mast, true)) | |
3408 | break; | |
3409 | ||
3410 | /* Try to push right. */ | |
3411 | if (mas_push_data(mas, height, &mast, false)) | |
3412 | break; | |
3413 | ||
3414 | split = mab_calc_split(mas, b_node, &mid_split, prev_l_mas.min); | |
3415 | mast_split_data(&mast, mas, split); | |
3416 | /* | |
3417 | * Usually correct, mab_mas_cp in the above call overwrites | |
3418 | * r->max. | |
3419 | */ | |
3420 | mast.r->max = mas->max; | |
3421 | mast_fill_bnode(&mast, mas, 1); | |
3422 | prev_l_mas = *mast.l; | |
3423 | prev_r_mas = *mast.r; | |
3424 | } | |
3425 | ||
3426 | /* Set the original node as dead */ | |
530f745c | 3427 | old = mas->node; |
54a611b6 | 3428 | mas->node = l_mas.node; |
530f745c | 3429 | mas_wmb_replace(mas, old); |
54a611b6 LH |
3430 | mtree_range_walk(mas); |
3431 | return 1; | |
3432 | } | |
3433 | ||
3434 | /* | |
3435 | * mas_reuse_node() - Reuse the node to store the data. | |
3436 | * @wr_mas: The maple write state | |
3437 | * @bn: The maple big node | |
3438 | * @end: The end of the data. | |
3439 | * | |
3440 | * Will always return false in RCU mode. | |
3441 | * | |
3442 | * Return: True if node was reused, false otherwise. | |
3443 | */ | |
3444 | static inline bool mas_reuse_node(struct ma_wr_state *wr_mas, | |
3445 | struct maple_big_node *bn, unsigned char end) | |
3446 | { | |
3447 | /* Need to be rcu safe. */ | |
3448 | if (mt_in_rcu(wr_mas->mas->tree)) | |
3449 | return false; | |
3450 | ||
3451 | if (end > bn->b_end) { | |
3452 | int clear = mt_slots[wr_mas->type] - bn->b_end; | |
3453 | ||
3454 | memset(wr_mas->slots + bn->b_end, 0, sizeof(void *) * clear--); | |
3455 | memset(wr_mas->pivots + bn->b_end, 0, sizeof(void *) * clear); | |
3456 | } | |
3457 | mab_mas_cp(bn, 0, bn->b_end, wr_mas->mas, false); | |
3458 | return true; | |
3459 | } | |
3460 | ||
3461 | /* | |
3462 | * mas_commit_b_node() - Commit the big node into the tree. | |
3463 | * @wr_mas: The maple write state | |
3464 | * @b_node: The maple big node | |
3465 | * @end: The end of the data. | |
3466 | */ | |
44081c77 | 3467 | static noinline_for_kasan int mas_commit_b_node(struct ma_wr_state *wr_mas, |
54a611b6 LH |
3468 | struct maple_big_node *b_node, unsigned char end) |
3469 | { | |
3470 | struct maple_node *node; | |
72bcf4aa | 3471 | struct maple_enode *old_enode; |
54a611b6 LH |
3472 | unsigned char b_end = b_node->b_end; |
3473 | enum maple_type b_type = b_node->type; | |
3474 | ||
72bcf4aa | 3475 | old_enode = wr_mas->mas->node; |
54a611b6 | 3476 | if ((b_end < mt_min_slots[b_type]) && |
72bcf4aa | 3477 | (!mte_is_root(old_enode)) && |
54a611b6 LH |
3478 | (mas_mt_height(wr_mas->mas) > 1)) |
3479 | return mas_rebalance(wr_mas->mas, b_node); | |
3480 | ||
3481 | if (b_end >= mt_slots[b_type]) | |
3482 | return mas_split(wr_mas->mas, b_node); | |
3483 | ||
3484 | if (mas_reuse_node(wr_mas, b_node, end)) | |
3485 | goto reuse_node; | |
3486 | ||
3487 | mas_node_count(wr_mas->mas, 1); | |
3488 | if (mas_is_err(wr_mas->mas)) | |
3489 | return 0; | |
3490 | ||
3491 | node = mas_pop_node(wr_mas->mas); | |
3492 | node->parent = mas_mn(wr_mas->mas)->parent; | |
3493 | wr_mas->mas->node = mt_mk_node(node, b_type); | |
7dc5ba62 | 3494 | mab_mas_cp(b_node, 0, b_end, wr_mas->mas, false); |
72bcf4aa | 3495 | mas_replace_node(wr_mas->mas, old_enode); |
54a611b6 LH |
3496 | reuse_node: |
3497 | mas_update_gap(wr_mas->mas); | |
3498 | return 1; | |
3499 | } | |
3500 | ||
3501 | /* | |
3502 | * mas_root_expand() - Expand a root to a node | |
3503 | * @mas: The maple state | |
3504 | * @entry: The entry to store into the tree | |
3505 | */ | |
3506 | static inline int mas_root_expand(struct ma_state *mas, void *entry) | |
3507 | { | |
3508 | void *contents = mas_root_locked(mas); | |
3509 | enum maple_type type = maple_leaf_64; | |
3510 | struct maple_node *node; | |
3511 | void __rcu **slots; | |
3512 | unsigned long *pivots; | |
3513 | int slot = 0; | |
3514 | ||
3515 | mas_node_count(mas, 1); | |
3516 | if (unlikely(mas_is_err(mas))) | |
3517 | return 0; | |
3518 | ||
3519 | node = mas_pop_node(mas); | |
3520 | pivots = ma_pivots(node, type); | |
3521 | slots = ma_slots(node, type); | |
4ffc2ee2 | 3522 | node->parent = ma_parent_ptr(mas_tree_parent(mas)); |
54a611b6 LH |
3523 | mas->node = mt_mk_node(node, type); |
3524 | ||
3525 | if (mas->index) { | |
3526 | if (contents) { | |
3527 | rcu_assign_pointer(slots[slot], contents); | |
3528 | if (likely(mas->index > 1)) | |
3529 | slot++; | |
3530 | } | |
3531 | pivots[slot++] = mas->index - 1; | |
3532 | } | |
3533 | ||
3534 | rcu_assign_pointer(slots[slot], entry); | |
3535 | mas->offset = slot; | |
3536 | pivots[slot] = mas->last; | |
3537 | if (mas->last != ULONG_MAX) | |
3c769fd8 PZ |
3538 | pivots[++slot] = ULONG_MAX; |
3539 | ||
54a611b6 LH |
3540 | mas->depth = 1; |
3541 | mas_set_height(mas); | |
c45ea315 | 3542 | ma_set_meta(node, maple_leaf_64, 0, slot); |
54a611b6 LH |
3543 | /* swap the new root into the tree */ |
3544 | rcu_assign_pointer(mas->tree->ma_root, mte_mk_root(mas->node)); | |
54a611b6 LH |
3545 | return slot; |
3546 | } | |
3547 | ||
3548 | static inline void mas_store_root(struct ma_state *mas, void *entry) | |
3549 | { | |
3550 | if (likely((mas->last != 0) || (mas->index != 0))) | |
3551 | mas_root_expand(mas, entry); | |
3552 | else if (((unsigned long) (entry) & 3) == 2) | |
3553 | mas_root_expand(mas, entry); | |
3554 | else { | |
3555 | rcu_assign_pointer(mas->tree->ma_root, entry); | |
3556 | mas->node = MAS_START; | |
3557 | } | |
3558 | } | |
3559 | ||
3560 | /* | |
3561 | * mas_is_span_wr() - Check if the write needs to be treated as a write that | |
3562 | * spans the node. | |
3563 | * @mas: The maple state | |
3564 | * @piv: The pivot value being written | |
3565 | * @type: The maple node type | |
3566 | * @entry: The data to write | |
3567 | * | |
3568 | * Spanning writes are writes that start in one node and end in another OR if | |
3569 | * the write of a %NULL will cause the node to end with a %NULL. | |
3570 | * | |
3571 | * Return: True if this is a spanning write, false otherwise. | |
3572 | */ | |
3573 | static bool mas_is_span_wr(struct ma_wr_state *wr_mas) | |
3574 | { | |
bc147f0f | 3575 | unsigned long max = wr_mas->r_max; |
54a611b6 | 3576 | unsigned long last = wr_mas->mas->last; |
54a611b6 LH |
3577 | enum maple_type type = wr_mas->type; |
3578 | void *entry = wr_mas->entry; | |
3579 | ||
bc147f0f PZ |
3580 | /* Contained in this pivot, fast path */ |
3581 | if (last < max) | |
54a611b6 LH |
3582 | return false; |
3583 | ||
bc147f0f PZ |
3584 | if (ma_is_leaf(type)) { |
3585 | max = wr_mas->mas->max; | |
54a611b6 LH |
3586 | if (last < max) |
3587 | return false; | |
bc147f0f | 3588 | } |
54a611b6 | 3589 | |
bc147f0f | 3590 | if (last == max) { |
54a611b6 | 3591 | /* |
bc147f0f PZ |
3592 | * The last entry of leaf node cannot be NULL unless it is the |
3593 | * rightmost node (writing ULONG_MAX), otherwise it spans slots. | |
54a611b6 | 3594 | */ |
bc147f0f | 3595 | if (entry || last == ULONG_MAX) |
54a611b6 LH |
3596 | return false; |
3597 | } | |
3598 | ||
bc147f0f | 3599 | trace_ma_write(__func__, wr_mas->mas, wr_mas->r_max, entry); |
54a611b6 LH |
3600 | return true; |
3601 | } | |
3602 | ||
3603 | static inline void mas_wr_walk_descend(struct ma_wr_state *wr_mas) | |
3604 | { | |
54a611b6 LH |
3605 | wr_mas->type = mte_node_type(wr_mas->mas->node); |
3606 | mas_wr_node_walk(wr_mas); | |
3607 | wr_mas->slots = ma_slots(wr_mas->node, wr_mas->type); | |
3608 | } | |
3609 | ||
3610 | static inline void mas_wr_walk_traverse(struct ma_wr_state *wr_mas) | |
3611 | { | |
3612 | wr_mas->mas->max = wr_mas->r_max; | |
3613 | wr_mas->mas->min = wr_mas->r_min; | |
3614 | wr_mas->mas->node = wr_mas->content; | |
3615 | wr_mas->mas->offset = 0; | |
9bbba563 | 3616 | wr_mas->mas->depth++; |
54a611b6 LH |
3617 | } |
3618 | /* | |
3619 | * mas_wr_walk() - Walk the tree for a write. | |
3620 | * @wr_mas: The maple write state | |
3621 | * | |
3622 | * Uses mas_slot_locked() and does not need to worry about dead nodes. | |
3623 | * | |
3624 | * Return: True if it's contained in a node, false on spanning write. | |
3625 | */ | |
3626 | static bool mas_wr_walk(struct ma_wr_state *wr_mas) | |
3627 | { | |
3628 | struct ma_state *mas = wr_mas->mas; | |
3629 | ||
3630 | while (true) { | |
3631 | mas_wr_walk_descend(wr_mas); | |
3632 | if (unlikely(mas_is_span_wr(wr_mas))) | |
3633 | return false; | |
3634 | ||
3635 | wr_mas->content = mas_slot_locked(mas, wr_mas->slots, | |
3636 | mas->offset); | |
3637 | if (ma_is_leaf(wr_mas->type)) | |
3638 | return true; | |
3639 | ||
3640 | mas_wr_walk_traverse(wr_mas); | |
3641 | } | |
3642 | ||
3643 | return true; | |
3644 | } | |
3645 | ||
3646 | static bool mas_wr_walk_index(struct ma_wr_state *wr_mas) | |
3647 | { | |
3648 | struct ma_state *mas = wr_mas->mas; | |
3649 | ||
3650 | while (true) { | |
3651 | mas_wr_walk_descend(wr_mas); | |
3652 | wr_mas->content = mas_slot_locked(mas, wr_mas->slots, | |
3653 | mas->offset); | |
3654 | if (ma_is_leaf(wr_mas->type)) | |
3655 | return true; | |
3656 | mas_wr_walk_traverse(wr_mas); | |
3657 | ||
3658 | } | |
3659 | return true; | |
3660 | } | |
3661 | /* | |
3662 | * mas_extend_spanning_null() - Extend a store of a %NULL to include surrounding %NULLs. | |
3663 | * @l_wr_mas: The left maple write state | |
3664 | * @r_wr_mas: The right maple write state | |
3665 | */ | |
3666 | static inline void mas_extend_spanning_null(struct ma_wr_state *l_wr_mas, | |
3667 | struct ma_wr_state *r_wr_mas) | |
3668 | { | |
3669 | struct ma_state *r_mas = r_wr_mas->mas; | |
3670 | struct ma_state *l_mas = l_wr_mas->mas; | |
3671 | unsigned char l_slot; | |
3672 | ||
3673 | l_slot = l_mas->offset; | |
3674 | if (!l_wr_mas->content) | |
3675 | l_mas->index = l_wr_mas->r_min; | |
3676 | ||
3677 | if ((l_mas->index == l_wr_mas->r_min) && | |
3678 | (l_slot && | |
3679 | !mas_slot_locked(l_mas, l_wr_mas->slots, l_slot - 1))) { | |
3680 | if (l_slot > 1) | |
3681 | l_mas->index = l_wr_mas->pivots[l_slot - 2] + 1; | |
3682 | else | |
3683 | l_mas->index = l_mas->min; | |
3684 | ||
3685 | l_mas->offset = l_slot - 1; | |
3686 | } | |
3687 | ||
3688 | if (!r_wr_mas->content) { | |
3689 | if (r_mas->last < r_wr_mas->r_max) | |
3690 | r_mas->last = r_wr_mas->r_max; | |
3691 | r_mas->offset++; | |
3692 | } else if ((r_mas->last == r_wr_mas->r_max) && | |
3693 | (r_mas->last < r_mas->max) && | |
3694 | !mas_slot_locked(r_mas, r_wr_mas->slots, r_mas->offset + 1)) { | |
3695 | r_mas->last = mas_safe_pivot(r_mas, r_wr_mas->pivots, | |
3696 | r_wr_mas->type, r_mas->offset + 1); | |
3697 | r_mas->offset++; | |
3698 | } | |
3699 | } | |
3700 | ||
3701 | static inline void *mas_state_walk(struct ma_state *mas) | |
3702 | { | |
3703 | void *entry; | |
3704 | ||
3705 | entry = mas_start(mas); | |
3706 | if (mas_is_none(mas)) | |
3707 | return NULL; | |
3708 | ||
3709 | if (mas_is_ptr(mas)) | |
3710 | return entry; | |
3711 | ||
3712 | return mtree_range_walk(mas); | |
3713 | } | |
3714 | ||
3715 | /* | |
3716 | * mtree_lookup_walk() - Internal quick lookup that does not keep maple state up | |
3717 | * to date. | |
3718 | * | |
3719 | * @mas: The maple state. | |
3720 | * | |
3721 | * Note: Leaves mas in undesirable state. | |
3722 | * Return: The entry for @mas->index or %NULL on dead node. | |
3723 | */ | |
3724 | static inline void *mtree_lookup_walk(struct ma_state *mas) | |
3725 | { | |
3726 | unsigned long *pivots; | |
3727 | unsigned char offset; | |
3728 | struct maple_node *node; | |
3729 | struct maple_enode *next; | |
3730 | enum maple_type type; | |
3731 | void __rcu **slots; | |
3732 | unsigned char end; | |
3733 | unsigned long max; | |
3734 | ||
3735 | next = mas->node; | |
3736 | max = ULONG_MAX; | |
3737 | do { | |
3738 | offset = 0; | |
3739 | node = mte_to_node(next); | |
3740 | type = mte_node_type(next); | |
3741 | pivots = ma_pivots(node, type); | |
3742 | end = ma_data_end(node, type, pivots, max); | |
3743 | if (unlikely(ma_dead_node(node))) | |
3744 | goto dead_node; | |
54a611b6 | 3745 | do { |
ec07967d PZ |
3746 | if (pivots[offset] >= mas->index) { |
3747 | max = pivots[offset]; | |
3748 | break; | |
3749 | } | |
3750 | } while (++offset < end); | |
54a611b6 | 3751 | |
54a611b6 LH |
3752 | slots = ma_slots(node, type); |
3753 | next = mt_slot(mas->tree, slots, offset); | |
3754 | if (unlikely(ma_dead_node(node))) | |
3755 | goto dead_node; | |
3756 | } while (!ma_is_leaf(type)); | |
3757 | ||
831978e3 | 3758 | return (void *)next; |
54a611b6 LH |
3759 | |
3760 | dead_node: | |
3761 | mas_reset(mas); | |
3762 | return NULL; | |
3763 | } | |
3764 | ||
530f745c | 3765 | static void mte_destroy_walk(struct maple_enode *, struct maple_tree *); |
54a611b6 LH |
3766 | /* |
3767 | * mas_new_root() - Create a new root node that only contains the entry passed | |
3768 | * in. | |
3769 | * @mas: The maple state | |
3770 | * @entry: The entry to store. | |
3771 | * | |
3772 | * Only valid when the index == 0 and the last == ULONG_MAX | |
3773 | * | |
3774 | * Return 0 on error, 1 on success. | |
3775 | */ | |
3776 | static inline int mas_new_root(struct ma_state *mas, void *entry) | |
3777 | { | |
3778 | struct maple_enode *root = mas_root_locked(mas); | |
3779 | enum maple_type type = maple_leaf_64; | |
3780 | struct maple_node *node; | |
3781 | void __rcu **slots; | |
3782 | unsigned long *pivots; | |
3783 | ||
3784 | if (!entry && !mas->index && mas->last == ULONG_MAX) { | |
3785 | mas->depth = 0; | |
3786 | mas_set_height(mas); | |
3787 | rcu_assign_pointer(mas->tree->ma_root, entry); | |
3788 | mas->node = MAS_START; | |
3789 | goto done; | |
3790 | } | |
3791 | ||
3792 | mas_node_count(mas, 1); | |
3793 | if (mas_is_err(mas)) | |
3794 | return 0; | |
3795 | ||
3796 | node = mas_pop_node(mas); | |
3797 | pivots = ma_pivots(node, type); | |
3798 | slots = ma_slots(node, type); | |
4ffc2ee2 | 3799 | node->parent = ma_parent_ptr(mas_tree_parent(mas)); |
54a611b6 LH |
3800 | mas->node = mt_mk_node(node, type); |
3801 | rcu_assign_pointer(slots[0], entry); | |
3802 | pivots[0] = mas->last; | |
3803 | mas->depth = 1; | |
3804 | mas_set_height(mas); | |
3805 | rcu_assign_pointer(mas->tree->ma_root, mte_mk_root(mas->node)); | |
3806 | ||
3807 | done: | |
3808 | if (xa_is_node(root)) | |
3809 | mte_destroy_walk(root, mas->tree); | |
3810 | ||
3811 | return 1; | |
3812 | } | |
3813 | /* | |
3814 | * mas_wr_spanning_store() - Create a subtree with the store operation completed | |
3815 | * and new nodes where necessary, then place the sub-tree in the actual tree. | |
3816 | * Note that mas is expected to point to the node which caused the store to | |
3817 | * span. | |
3818 | * @wr_mas: The maple write state | |
3819 | * | |
3820 | * Return: 0 on error, positive on success. | |
3821 | */ | |
3822 | static inline int mas_wr_spanning_store(struct ma_wr_state *wr_mas) | |
3823 | { | |
3824 | struct maple_subtree_state mast; | |
3825 | struct maple_big_node b_node; | |
3826 | struct ma_state *mas; | |
3827 | unsigned char height; | |
3828 | ||
3829 | /* Left and Right side of spanning store */ | |
3830 | MA_STATE(l_mas, NULL, 0, 0); | |
3831 | MA_STATE(r_mas, NULL, 0, 0); | |
54a611b6 LH |
3832 | MA_WR_STATE(r_wr_mas, &r_mas, wr_mas->entry); |
3833 | MA_WR_STATE(l_wr_mas, &l_mas, wr_mas->entry); | |
3834 | ||
3835 | /* | |
3836 | * A store operation that spans multiple nodes is called a spanning | |
3837 | * store and is handled early in the store call stack by the function | |
3838 | * mas_is_span_wr(). When a spanning store is identified, the maple | |
3839 | * state is duplicated. The first maple state walks the left tree path | |
3840 | * to ``index``, the duplicate walks the right tree path to ``last``. | |
3841 | * The data in the two nodes are combined into a single node, two nodes, | |
3842 | * or possibly three nodes (see the 3-way split above). A ``NULL`` | |
3843 | * written to the last entry of a node is considered a spanning store as | |
3844 | * a rebalance is required for the operation to complete and an overflow | |
3845 | * of data may happen. | |
3846 | */ | |
3847 | mas = wr_mas->mas; | |
3848 | trace_ma_op(__func__, mas); | |
3849 | ||
3850 | if (unlikely(!mas->index && mas->last == ULONG_MAX)) | |
3851 | return mas_new_root(mas, wr_mas->entry); | |
3852 | /* | |
3853 | * Node rebalancing may occur due to this store, so there may be three new | |
3854 | * entries per level plus a new root. | |
3855 | */ | |
3856 | height = mas_mt_height(mas); | |
3857 | mas_node_count(mas, 1 + height * 3); | |
3858 | if (mas_is_err(mas)) | |
3859 | return 0; | |
3860 | ||
3861 | /* | |
3862 | * Set up right side. Need to get to the next offset after the spanning | |
3863 | * store to ensure it's not NULL and to combine both the next node and | |
3864 | * the node with the start together. | |
3865 | */ | |
3866 | r_mas = *mas; | |
3867 | /* Avoid overflow, walk to next slot in the tree. */ | |
3868 | if (r_mas.last + 1) | |
3869 | r_mas.last++; | |
3870 | ||
3871 | r_mas.index = r_mas.last; | |
3872 | mas_wr_walk_index(&r_wr_mas); | |
3873 | r_mas.last = r_mas.index = mas->last; | |
3874 | ||
3875 | /* Set up left side. */ | |
3876 | l_mas = *mas; | |
3877 | mas_wr_walk_index(&l_wr_mas); | |
3878 | ||
3879 | if (!wr_mas->entry) { | |
3880 | mas_extend_spanning_null(&l_wr_mas, &r_wr_mas); | |
3881 | mas->offset = l_mas.offset; | |
3882 | mas->index = l_mas.index; | |
3883 | mas->last = l_mas.last = r_mas.last; | |
3884 | } | |
3885 | ||
3886 | /* expanding NULLs may make this cover the entire range */ | |
3887 | if (!l_mas.index && r_mas.last == ULONG_MAX) { | |
3888 | mas_set_range(mas, 0, ULONG_MAX); | |
3889 | return mas_new_root(mas, wr_mas->entry); | |
3890 | } | |
3891 | ||
3892 | memset(&b_node, 0, sizeof(struct maple_big_node)); | |
3893 | /* Copy l_mas and store the value in b_node. */ | |
3894 | mas_store_b_node(&l_wr_mas, &b_node, l_wr_mas.node_end); | |
3895 | /* Copy r_mas into b_node. */ | |
3896 | if (r_mas.offset <= r_wr_mas.node_end) | |
3897 | mas_mab_cp(&r_mas, r_mas.offset, r_wr_mas.node_end, | |
3898 | &b_node, b_node.b_end + 1); | |
3899 | else | |
3900 | b_node.b_end++; | |
3901 | ||
3902 | /* Stop spanning searches by searching for just index. */ | |
3903 | l_mas.index = l_mas.last = mas->index; | |
3904 | ||
3905 | mast.bn = &b_node; | |
3906 | mast.orig_l = &l_mas; | |
3907 | mast.orig_r = &r_mas; | |
3908 | /* Combine l_mas and r_mas and split them up evenly again. */ | |
3909 | return mas_spanning_rebalance(mas, &mast, height + 1); | |
3910 | } | |
3911 | ||
3912 | /* | |
3913 | * mas_wr_node_store() - Attempt to store the value in a node | |
3914 | * @wr_mas: The maple write state | |
3915 | * | |
3916 | * Attempts to reuse the node, but may allocate. | |
3917 | * | |
3918 | * Return: True if stored, false otherwise | |
3919 | */ | |
7a03ae39 PZ |
3920 | static inline bool mas_wr_node_store(struct ma_wr_state *wr_mas, |
3921 | unsigned char new_end) | |
54a611b6 LH |
3922 | { |
3923 | struct ma_state *mas = wr_mas->mas; | |
3924 | void __rcu **dst_slots; | |
3925 | unsigned long *dst_pivots; | |
7a03ae39 | 3926 | unsigned char dst_offset, offset_end = wr_mas->offset_end; |
54a611b6 | 3927 | struct maple_node reuse, *newnode; |
7a03ae39 | 3928 | unsigned char copy_size, node_pivots = mt_pivots[wr_mas->type]; |
54a611b6 LH |
3929 | bool in_rcu = mt_in_rcu(mas->tree); |
3930 | ||
7a03ae39 | 3931 | /* Check if there is enough data. The room is enough. */ |
54a611b6 LH |
3932 | if (!mte_is_root(mas->node) && (new_end <= mt_min_slots[wr_mas->type]) && |
3933 | !(mas->mas_flags & MA_STATE_BULK)) | |
3934 | return false; | |
3935 | ||
7a03ae39 PZ |
3936 | if (mas->last == wr_mas->end_piv) |
3937 | offset_end++; /* don't copy this offset */ | |
3938 | else if (unlikely(wr_mas->r_max == ULONG_MAX)) | |
3939 | mas_bulk_rebalance(mas, wr_mas->node_end, wr_mas->type); | |
3940 | ||
54a611b6 LH |
3941 | /* set up node. */ |
3942 | if (in_rcu) { | |
3943 | mas_node_count(mas, 1); | |
3944 | if (mas_is_err(mas)) | |
3945 | return false; | |
3946 | ||
3947 | newnode = mas_pop_node(mas); | |
3948 | } else { | |
3949 | memset(&reuse, 0, sizeof(struct maple_node)); | |
3950 | newnode = &reuse; | |
3951 | } | |
3952 | ||
3953 | newnode->parent = mas_mn(mas)->parent; | |
3954 | dst_pivots = ma_pivots(newnode, wr_mas->type); | |
3955 | dst_slots = ma_slots(newnode, wr_mas->type); | |
3956 | /* Copy from start to insert point */ | |
7a03ae39 PZ |
3957 | memcpy(dst_pivots, wr_mas->pivots, sizeof(unsigned long) * mas->offset); |
3958 | memcpy(dst_slots, wr_mas->slots, sizeof(void *) * mas->offset); | |
54a611b6 LH |
3959 | |
3960 | /* Handle insert of new range starting after old range */ | |
3961 | if (wr_mas->r_min < mas->index) { | |
7a03ae39 PZ |
3962 | rcu_assign_pointer(dst_slots[mas->offset], wr_mas->content); |
3963 | dst_pivots[mas->offset++] = mas->index - 1; | |
54a611b6 LH |
3964 | } |
3965 | ||
3966 | /* Store the new entry and range end. */ | |
7a03ae39 PZ |
3967 | if (mas->offset < node_pivots) |
3968 | dst_pivots[mas->offset] = mas->last; | |
3969 | rcu_assign_pointer(dst_slots[mas->offset], wr_mas->entry); | |
54a611b6 LH |
3970 | |
3971 | /* | |
3972 | * this range wrote to the end of the node or it overwrote the rest of | |
3973 | * the data | |
3974 | */ | |
7a03ae39 | 3975 | if (offset_end > wr_mas->node_end) |
54a611b6 | 3976 | goto done; |
54a611b6 | 3977 | |
7a03ae39 | 3978 | dst_offset = mas->offset + 1; |
54a611b6 | 3979 | /* Copy to the end of node if necessary. */ |
7a03ae39 PZ |
3980 | copy_size = wr_mas->node_end - offset_end + 1; |
3981 | memcpy(dst_slots + dst_offset, wr_mas->slots + offset_end, | |
54a611b6 | 3982 | sizeof(void *) * copy_size); |
7a03ae39 PZ |
3983 | memcpy(dst_pivots + dst_offset, wr_mas->pivots + offset_end, |
3984 | sizeof(unsigned long) * (copy_size - 1)); | |
54a611b6 | 3985 | |
7a03ae39 | 3986 | if (new_end < node_pivots) |
54a611b6 LH |
3987 | dst_pivots[new_end] = mas->max; |
3988 | ||
3989 | done: | |
3990 | mas_leaf_set_meta(mas, newnode, dst_pivots, maple_leaf_64, new_end); | |
3991 | if (in_rcu) { | |
72bcf4aa LH |
3992 | struct maple_enode *old_enode = mas->node; |
3993 | ||
54a611b6 | 3994 | mas->node = mt_mk_node(newnode, wr_mas->type); |
72bcf4aa | 3995 | mas_replace_node(mas, old_enode); |
54a611b6 LH |
3996 | } else { |
3997 | memcpy(wr_mas->node, newnode, sizeof(struct maple_node)); | |
3998 | } | |
3999 | trace_ma_write(__func__, mas, 0, wr_mas->entry); | |
4000 | mas_update_gap(mas); | |
4001 | return true; | |
4002 | } | |
4003 | ||
4004 | /* | |
4005 | * mas_wr_slot_store: Attempt to store a value in a slot. | |
4006 | * @wr_mas: the maple write state | |
4007 | * | |
4008 | * Return: True if stored, false otherwise | |
4009 | */ | |
4010 | static inline bool mas_wr_slot_store(struct ma_wr_state *wr_mas) | |
4011 | { | |
4012 | struct ma_state *mas = wr_mas->mas; | |
54a611b6 | 4013 | unsigned char offset = mas->offset; |
64891ba3 | 4014 | void __rcu **slots = wr_mas->slots; |
e6d1ffd6 | 4015 | bool gap = false; |
54a611b6 | 4016 | |
64891ba3 PZ |
4017 | gap |= !mt_slot_locked(mas->tree, slots, offset); |
4018 | gap |= !mt_slot_locked(mas->tree, slots, offset + 1); | |
54a611b6 | 4019 | |
64891ba3 PZ |
4020 | if (wr_mas->offset_end - offset == 1) { |
4021 | if (mas->index == wr_mas->r_min) { | |
4022 | /* Overwriting the range and a part of the next one */ | |
4023 | rcu_assign_pointer(slots[offset], wr_mas->entry); | |
4024 | wr_mas->pivots[offset] = mas->last; | |
4025 | } else { | |
4026 | /* Overwriting a part of the range and the next one */ | |
4027 | rcu_assign_pointer(slots[offset + 1], wr_mas->entry); | |
4028 | wr_mas->pivots[offset] = mas->index - 1; | |
4029 | mas->offset++; /* Keep mas accurate. */ | |
4030 | } | |
4031 | } else if (!mt_in_rcu(mas->tree)) { | |
4032 | /* | |
4033 | * Expand the range, only partially overwriting the previous and | |
4034 | * next ranges | |
4035 | */ | |
4036 | gap |= !mt_slot_locked(mas->tree, slots, offset + 2); | |
4037 | rcu_assign_pointer(slots[offset + 1], wr_mas->entry); | |
e6d1ffd6 | 4038 | wr_mas->pivots[offset] = mas->index - 1; |
64891ba3 | 4039 | wr_mas->pivots[offset + 1] = mas->last; |
e6d1ffd6 | 4040 | mas->offset++; /* Keep mas accurate. */ |
64891ba3 PZ |
4041 | } else { |
4042 | return false; | |
54a611b6 LH |
4043 | } |
4044 | ||
54a611b6 | 4045 | trace_ma_write(__func__, mas, 0, wr_mas->entry); |
e6d1ffd6 PZ |
4046 | /* |
4047 | * Only update gap when the new entry is empty or there is an empty | |
4048 | * entry in the original two ranges. | |
4049 | */ | |
4050 | if (!wr_mas->entry || gap) | |
4051 | mas_update_gap(mas); | |
4052 | ||
54a611b6 LH |
4053 | return true; |
4054 | } | |
4055 | ||
54a611b6 LH |
4056 | static inline void mas_wr_extend_null(struct ma_wr_state *wr_mas) |
4057 | { | |
4058 | struct ma_state *mas = wr_mas->mas; | |
4059 | ||
8c995a63 PZ |
4060 | if (!wr_mas->slots[wr_mas->offset_end]) { |
4061 | /* If this one is null, the next and prev are not */ | |
54a611b6 | 4062 | mas->last = wr_mas->end_piv; |
8c995a63 PZ |
4063 | } else { |
4064 | /* Check next slot(s) if we are overwriting the end */ | |
4065 | if ((mas->last == wr_mas->end_piv) && | |
4066 | (wr_mas->node_end != wr_mas->offset_end) && | |
4067 | !wr_mas->slots[wr_mas->offset_end + 1]) { | |
4068 | wr_mas->offset_end++; | |
4069 | if (wr_mas->offset_end == wr_mas->node_end) | |
4070 | mas->last = mas->max; | |
4071 | else | |
4072 | mas->last = wr_mas->pivots[wr_mas->offset_end]; | |
4073 | wr_mas->end_piv = mas->last; | |
4074 | } | |
54a611b6 LH |
4075 | } |
4076 | ||
4077 | if (!wr_mas->content) { | |
4078 | /* If this one is null, the next and prev are not */ | |
4079 | mas->index = wr_mas->r_min; | |
4080 | } else { | |
4081 | /* Check prev slot if we are overwriting the start */ | |
4082 | if (mas->index == wr_mas->r_min && mas->offset && | |
4083 | !wr_mas->slots[mas->offset - 1]) { | |
4084 | mas->offset--; | |
4085 | wr_mas->r_min = mas->index = | |
4086 | mas_safe_min(mas, wr_mas->pivots, mas->offset); | |
4087 | wr_mas->r_max = wr_mas->pivots[mas->offset]; | |
4088 | } | |
4089 | } | |
4090 | } | |
4091 | ||
a7496ad5 LH |
4092 | static inline void mas_wr_end_piv(struct ma_wr_state *wr_mas) |
4093 | { | |
4094 | while ((wr_mas->offset_end < wr_mas->node_end) && | |
4095 | (wr_mas->mas->last > wr_mas->pivots[wr_mas->offset_end])) | |
4096 | wr_mas->offset_end++; | |
4097 | ||
4098 | if (wr_mas->offset_end < wr_mas->node_end) | |
4099 | wr_mas->end_piv = wr_mas->pivots[wr_mas->offset_end]; | |
4100 | else | |
4101 | wr_mas->end_piv = wr_mas->mas->max; | |
4102 | ||
4103 | if (!wr_mas->entry) | |
4104 | mas_wr_extend_null(wr_mas); | |
4105 | } | |
4106 | ||
c6fc9e4a PZ |
4107 | static inline unsigned char mas_wr_new_end(struct ma_wr_state *wr_mas) |
4108 | { | |
4109 | struct ma_state *mas = wr_mas->mas; | |
4110 | unsigned char new_end = wr_mas->node_end + 2; | |
4111 | ||
4112 | new_end -= wr_mas->offset_end - mas->offset; | |
4113 | if (wr_mas->r_min == mas->index) | |
4114 | new_end--; | |
4115 | ||
4116 | if (wr_mas->end_piv == mas->last) | |
4117 | new_end--; | |
4118 | ||
4119 | return new_end; | |
4120 | } | |
4121 | ||
2e1da329 PZ |
4122 | /* |
4123 | * mas_wr_append: Attempt to append | |
4124 | * @wr_mas: the maple write state | |
432af5c9 | 4125 | * @new_end: The end of the node after the modification |
2e1da329 | 4126 | * |
cfeb6ae8 LH |
4127 | * This is currently unsafe in rcu mode since the end of the node may be cached |
4128 | * by readers while the node contents may be updated which could result in | |
4129 | * inaccurate information. | |
4130 | * | |
2e1da329 PZ |
4131 | * Return: True if appended, false otherwise |
4132 | */ | |
23e9dde0 | 4133 | static inline bool mas_wr_append(struct ma_wr_state *wr_mas, |
432af5c9 | 4134 | unsigned char new_end) |
54a611b6 | 4135 | { |
432af5c9 LH |
4136 | struct ma_state *mas; |
4137 | void __rcu **slots; | |
4138 | unsigned char end; | |
54a611b6 | 4139 | |
432af5c9 | 4140 | mas = wr_mas->mas; |
cfeb6ae8 LH |
4141 | if (mt_in_rcu(mas->tree)) |
4142 | return false; | |
4143 | ||
2e1da329 PZ |
4144 | if (mas->offset != wr_mas->node_end) |
4145 | return false; | |
54a611b6 | 4146 | |
432af5c9 LH |
4147 | end = wr_mas->node_end; |
4148 | if (mas->offset != end) | |
4149 | return false; | |
4150 | ||
4151 | if (new_end < mt_pivots[wr_mas->type]) { | |
2e1da329 | 4152 | wr_mas->pivots[new_end] = wr_mas->pivots[end]; |
432af5c9 | 4153 | ma_set_meta(wr_mas->node, wr_mas->type, 0, new_end); |
2e1da329 | 4154 | } |
54a611b6 | 4155 | |
432af5c9 LH |
4156 | slots = wr_mas->slots; |
4157 | if (new_end == end + 1) { | |
23e9dde0 PZ |
4158 | if (mas->last == wr_mas->r_max) { |
4159 | /* Append to end of range */ | |
432af5c9 | 4160 | rcu_assign_pointer(slots[new_end], wr_mas->entry); |
23e9dde0 PZ |
4161 | wr_mas->pivots[end] = mas->index - 1; |
4162 | mas->offset = new_end; | |
4163 | } else { | |
4164 | /* Append to start of range */ | |
432af5c9 | 4165 | rcu_assign_pointer(slots[new_end], wr_mas->content); |
23e9dde0 | 4166 | wr_mas->pivots[end] = mas->last; |
432af5c9 | 4167 | rcu_assign_pointer(slots[end], wr_mas->entry); |
23e9dde0 | 4168 | } |
2e1da329 | 4169 | } else { |
23e9dde0 | 4170 | /* Append to the range without touching any boundaries. */ |
432af5c9 | 4171 | rcu_assign_pointer(slots[new_end], wr_mas->content); |
23e9dde0 | 4172 | wr_mas->pivots[end + 1] = mas->last; |
432af5c9 | 4173 | rcu_assign_pointer(slots[end + 1], wr_mas->entry); |
23e9dde0 PZ |
4174 | wr_mas->pivots[end] = mas->index - 1; |
4175 | mas->offset = end + 1; | |
54a611b6 LH |
4176 | } |
4177 | ||
2e1da329 PZ |
4178 | if (!wr_mas->content || !wr_mas->entry) |
4179 | mas_update_gap(mas); | |
4180 | ||
432af5c9 | 4181 | trace_ma_write(__func__, mas, new_end, wr_mas->entry); |
2e1da329 | 4182 | return true; |
54a611b6 LH |
4183 | } |
4184 | ||
4185 | /* | |
4186 | * mas_wr_bnode() - Slow path for a modification. | |
4187 | * @wr_mas: The write maple state | |
4188 | * | |
4189 | * This is where split, rebalance end up. | |
4190 | */ | |
4191 | static void mas_wr_bnode(struct ma_wr_state *wr_mas) | |
4192 | { | |
4193 | struct maple_big_node b_node; | |
4194 | ||
4195 | trace_ma_write(__func__, wr_mas->mas, 0, wr_mas->entry); | |
4196 | memset(&b_node, 0, sizeof(struct maple_big_node)); | |
4197 | mas_store_b_node(wr_mas, &b_node, wr_mas->offset_end); | |
4198 | mas_commit_b_node(wr_mas, &b_node, wr_mas->node_end); | |
4199 | } | |
4200 | ||
4201 | static inline void mas_wr_modify(struct ma_wr_state *wr_mas) | |
4202 | { | |
54a611b6 | 4203 | struct ma_state *mas = wr_mas->mas; |
c6fc9e4a | 4204 | unsigned char new_end; |
54a611b6 LH |
4205 | |
4206 | /* Direct replacement */ | |
4207 | if (wr_mas->r_min == mas->index && wr_mas->r_max == mas->last) { | |
4208 | rcu_assign_pointer(wr_mas->slots[mas->offset], wr_mas->entry); | |
4209 | if (!!wr_mas->entry ^ !!wr_mas->content) | |
4210 | mas_update_gap(mas); | |
4211 | return; | |
4212 | } | |
4213 | ||
c6fc9e4a PZ |
4214 | /* |
4215 | * new_end exceeds the size of the maple node and cannot enter the fast | |
4216 | * path. | |
4217 | */ | |
4218 | new_end = mas_wr_new_end(wr_mas); | |
4219 | if (new_end >= mt_slots[wr_mas->type]) | |
54a611b6 LH |
4220 | goto slow_path; |
4221 | ||
2e1da329 | 4222 | /* Attempt to append */ |
23e9dde0 | 4223 | if (mas_wr_append(wr_mas, new_end)) |
54a611b6 | 4224 | return; |
54a611b6 | 4225 | |
e6d1ffd6 | 4226 | if (new_end == wr_mas->node_end && mas_wr_slot_store(wr_mas)) |
54a611b6 | 4227 | return; |
7a03ae39 PZ |
4228 | |
4229 | if (mas_wr_node_store(wr_mas, new_end)) | |
54a611b6 LH |
4230 | return; |
4231 | ||
4232 | if (mas_is_err(mas)) | |
4233 | return; | |
4234 | ||
4235 | slow_path: | |
4236 | mas_wr_bnode(wr_mas); | |
4237 | } | |
4238 | ||
4239 | /* | |
4240 | * mas_wr_store_entry() - Internal call to store a value | |
4241 | * @mas: The maple state | |
4242 | * @entry: The entry to store. | |
4243 | * | |
4244 | * Return: The contents that was stored at the index. | |
4245 | */ | |
4246 | static inline void *mas_wr_store_entry(struct ma_wr_state *wr_mas) | |
4247 | { | |
4248 | struct ma_state *mas = wr_mas->mas; | |
4249 | ||
4250 | wr_mas->content = mas_start(mas); | |
4251 | if (mas_is_none(mas) || mas_is_ptr(mas)) { | |
4252 | mas_store_root(mas, wr_mas->entry); | |
4253 | return wr_mas->content; | |
4254 | } | |
4255 | ||
4256 | if (unlikely(!mas_wr_walk(wr_mas))) { | |
4257 | mas_wr_spanning_store(wr_mas); | |
4258 | return wr_mas->content; | |
4259 | } | |
4260 | ||
4261 | /* At this point, we are at the leaf node that needs to be altered. */ | |
54a611b6 | 4262 | mas_wr_end_piv(wr_mas); |
54a611b6 LH |
4263 | /* New root for a single pointer */ |
4264 | if (unlikely(!mas->index && mas->last == ULONG_MAX)) { | |
4265 | mas_new_root(mas, wr_mas->entry); | |
4266 | return wr_mas->content; | |
4267 | } | |
4268 | ||
4269 | mas_wr_modify(wr_mas); | |
4270 | return wr_mas->content; | |
4271 | } | |
4272 | ||
4273 | /** | |
4274 | * mas_insert() - Internal call to insert a value | |
4275 | * @mas: The maple state | |
4276 | * @entry: The entry to store | |
4277 | * | |
4278 | * Return: %NULL or the contents that already exists at the requested index | |
4279 | * otherwise. The maple state needs to be checked for error conditions. | |
4280 | */ | |
4281 | static inline void *mas_insert(struct ma_state *mas, void *entry) | |
4282 | { | |
4283 | MA_WR_STATE(wr_mas, mas, entry); | |
4284 | ||
4285 | /* | |
4286 | * Inserting a new range inserts either 0, 1, or 2 pivots within the | |
4287 | * tree. If the insert fits exactly into an existing gap with a value | |
4288 | * of NULL, then the slot only needs to be written with the new value. | |
4289 | * If the range being inserted is adjacent to another range, then only a | |
4290 | * single pivot needs to be inserted (as well as writing the entry). If | |
4291 | * the new range is within a gap but does not touch any other ranges, | |
4292 | * then two pivots need to be inserted: the start - 1, and the end. As | |
4293 | * usual, the entry must be written. Most operations require a new node | |
4294 | * to be allocated and replace an existing node to ensure RCU safety, | |
4295 | * when in RCU mode. The exception to requiring a newly allocated node | |
4296 | * is when inserting at the end of a node (appending). When done | |
4297 | * carefully, appending can reuse the node in place. | |
4298 | */ | |
4299 | wr_mas.content = mas_start(mas); | |
4300 | if (wr_mas.content) | |
4301 | goto exists; | |
4302 | ||
4303 | if (mas_is_none(mas) || mas_is_ptr(mas)) { | |
4304 | mas_store_root(mas, entry); | |
4305 | return NULL; | |
4306 | } | |
4307 | ||
4308 | /* spanning writes always overwrite something */ | |
4309 | if (!mas_wr_walk(&wr_mas)) | |
4310 | goto exists; | |
4311 | ||
4312 | /* At this point, we are at the leaf node that needs to be altered. */ | |
4313 | wr_mas.offset_end = mas->offset; | |
4314 | wr_mas.end_piv = wr_mas.r_max; | |
4315 | ||
4316 | if (wr_mas.content || (mas->last > wr_mas.r_max)) | |
4317 | goto exists; | |
4318 | ||
4319 | if (!entry) | |
4320 | return NULL; | |
4321 | ||
4322 | mas_wr_modify(&wr_mas); | |
4323 | return wr_mas.content; | |
4324 | ||
4325 | exists: | |
4326 | mas_set_err(mas, -EEXIST); | |
4327 | return wr_mas.content; | |
4328 | ||
4329 | } | |
4330 | ||
de6e386c LH |
4331 | static inline void mas_rewalk(struct ma_state *mas, unsigned long index) |
4332 | { | |
4333 | retry: | |
4334 | mas_set(mas, index); | |
4335 | mas_state_walk(mas); | |
4336 | if (mas_is_start(mas)) | |
4337 | goto retry; | |
4338 | } | |
4339 | ||
4340 | static inline bool mas_rewalk_if_dead(struct ma_state *mas, | |
4341 | struct maple_node *node, const unsigned long index) | |
4342 | { | |
4343 | if (unlikely(ma_dead_node(node))) { | |
4344 | mas_rewalk(mas, index); | |
4345 | return true; | |
4346 | } | |
4347 | return false; | |
4348 | } | |
4349 | ||
54a611b6 LH |
4350 | /* |
4351 | * mas_prev_node() - Find the prev non-null entry at the same level in the | |
4352 | * tree. The prev value will be mas->node[mas->offset] or MAS_NONE. | |
4353 | * @mas: The maple state | |
4354 | * @min: The lower limit to search | |
4355 | * | |
4356 | * The prev node value will be mas->node[mas->offset] or MAS_NONE. | |
4357 | * Return: 1 if the node is dead, 0 otherwise. | |
4358 | */ | |
4359 | static inline int mas_prev_node(struct ma_state *mas, unsigned long min) | |
4360 | { | |
4361 | enum maple_type mt; | |
4362 | int offset, level; | |
4363 | void __rcu **slots; | |
4364 | struct maple_node *node; | |
54a611b6 | 4365 | unsigned long *pivots; |
dd9a8513 | 4366 | unsigned long max; |
54a611b6 | 4367 | |
dd9a8513 LH |
4368 | node = mas_mn(mas); |
4369 | if (!mas->min) | |
4370 | goto no_entry; | |
4371 | ||
4372 | max = mas->min - 1; | |
4373 | if (max < min) | |
4374 | goto no_entry; | |
54a611b6 LH |
4375 | |
4376 | level = 0; | |
4377 | do { | |
54a611b6 LH |
4378 | if (ma_is_root(node)) |
4379 | goto no_entry; | |
4380 | ||
4381 | /* Walk up. */ | |
4382 | if (unlikely(mas_ascend(mas))) | |
4383 | return 1; | |
4384 | offset = mas->offset; | |
4385 | level++; | |
dd9a8513 | 4386 | node = mas_mn(mas); |
54a611b6 LH |
4387 | } while (!offset); |
4388 | ||
4389 | offset--; | |
4390 | mt = mte_node_type(mas->node); | |
54a611b6 LH |
4391 | while (level > 1) { |
4392 | level--; | |
dd9a8513 LH |
4393 | slots = ma_slots(node, mt); |
4394 | mas->node = mas_slot(mas, slots, offset); | |
54a611b6 LH |
4395 | if (unlikely(ma_dead_node(node))) |
4396 | return 1; | |
4397 | ||
54a611b6 LH |
4398 | mt = mte_node_type(mas->node); |
4399 | node = mas_mn(mas); | |
54a611b6 | 4400 | pivots = ma_pivots(node, mt); |
dd9a8513 | 4401 | offset = ma_data_end(node, mt, pivots, max); |
39d0bd86 LH |
4402 | if (unlikely(ma_dead_node(node))) |
4403 | return 1; | |
54a611b6 LH |
4404 | } |
4405 | ||
dd9a8513 | 4406 | slots = ma_slots(node, mt); |
54a611b6 | 4407 | mas->node = mas_slot(mas, slots, offset); |
dd9a8513 | 4408 | pivots = ma_pivots(node, mt); |
54a611b6 LH |
4409 | if (unlikely(ma_dead_node(node))) |
4410 | return 1; | |
4411 | ||
dd9a8513 LH |
4412 | if (likely(offset)) |
4413 | mas->min = pivots[offset - 1] + 1; | |
4414 | mas->max = max; | |
54a611b6 LH |
4415 | mas->offset = mas_data_end(mas); |
4416 | if (unlikely(mte_dead_node(mas->node))) | |
4417 | return 1; | |
4418 | ||
4419 | return 0; | |
4420 | ||
54a611b6 LH |
4421 | no_entry: |
4422 | if (unlikely(ma_dead_node(node))) | |
4423 | return 1; | |
4424 | ||
4425 | mas->node = MAS_NONE; | |
4426 | return 0; | |
4427 | } | |
4428 | ||
dd9a8513 LH |
4429 | /* |
4430 | * mas_prev_slot() - Get the entry in the previous slot | |
4431 | * | |
4432 | * @mas: The maple state | |
4433 | * @max: The minimum starting range | |
a8091f03 LH |
4434 | * @empty: Can be empty |
4435 | * @set_underflow: Set the @mas->node to underflow state on limit. | |
dd9a8513 LH |
4436 | * |
4437 | * Return: The entry in the previous slot which is possibly NULL | |
4438 | */ | |
a8091f03 LH |
4439 | static void *mas_prev_slot(struct ma_state *mas, unsigned long min, bool empty, |
4440 | bool set_underflow) | |
dd9a8513 LH |
4441 | { |
4442 | void *entry; | |
4443 | void __rcu **slots; | |
4444 | unsigned long pivot; | |
4445 | enum maple_type type; | |
4446 | unsigned long *pivots; | |
4447 | struct maple_node *node; | |
4448 | unsigned long save_point = mas->index; | |
4449 | ||
4450 | retry: | |
4451 | node = mas_mn(mas); | |
4452 | type = mte_node_type(mas->node); | |
4453 | pivots = ma_pivots(node, type); | |
4454 | if (unlikely(mas_rewalk_if_dead(mas, node, save_point))) | |
4455 | goto retry; | |
4456 | ||
dd9a8513 LH |
4457 | if (mas->min <= min) { |
4458 | pivot = mas_safe_min(mas, pivots, mas->offset); | |
4459 | ||
4460 | if (unlikely(mas_rewalk_if_dead(mas, node, save_point))) | |
4461 | goto retry; | |
4462 | ||
4463 | if (pivot <= min) | |
a8091f03 | 4464 | goto underflow; |
dd9a8513 LH |
4465 | } |
4466 | ||
a8091f03 | 4467 | again: |
dd9a8513 LH |
4468 | if (likely(mas->offset)) { |
4469 | mas->offset--; | |
4470 | mas->last = mas->index - 1; | |
4471 | mas->index = mas_safe_min(mas, pivots, mas->offset); | |
4472 | } else { | |
4473 | if (mas_prev_node(mas, min)) { | |
4474 | mas_rewalk(mas, save_point); | |
4475 | goto retry; | |
4476 | } | |
4477 | ||
4478 | if (mas_is_none(mas)) | |
a8091f03 | 4479 | goto underflow; |
dd9a8513 LH |
4480 | |
4481 | mas->last = mas->max; | |
4482 | node = mas_mn(mas); | |
4483 | type = mte_node_type(mas->node); | |
4484 | pivots = ma_pivots(node, type); | |
4485 | mas->index = pivots[mas->offset - 1] + 1; | |
4486 | } | |
4487 | ||
4488 | slots = ma_slots(node, type); | |
4489 | entry = mas_slot(mas, slots, mas->offset); | |
4490 | if (unlikely(mas_rewalk_if_dead(mas, node, save_point))) | |
4491 | goto retry; | |
4492 | ||
4493 | if (likely(entry)) | |
4494 | return entry; | |
4495 | ||
a8091f03 LH |
4496 | if (!empty) { |
4497 | if (mas->index <= min) | |
4498 | goto underflow; | |
4499 | ||
dd9a8513 | 4500 | goto again; |
a8091f03 | 4501 | } |
dd9a8513 LH |
4502 | |
4503 | return entry; | |
a8091f03 LH |
4504 | |
4505 | underflow: | |
4506 | if (set_underflow) | |
4507 | mas->node = MAS_UNDERFLOW; | |
4508 | return NULL; | |
dd9a8513 LH |
4509 | } |
4510 | ||
54a611b6 LH |
4511 | /* |
4512 | * mas_next_node() - Get the next node at the same level in the tree. | |
4513 | * @mas: The maple state | |
4514 | * @max: The maximum pivot value to check. | |
4515 | * | |
4516 | * The next value will be mas->node[mas->offset] or MAS_NONE. | |
4517 | * Return: 1 on dead node, 0 otherwise. | |
4518 | */ | |
4519 | static inline int mas_next_node(struct ma_state *mas, struct maple_node *node, | |
4520 | unsigned long max) | |
4521 | { | |
fff4a58c | 4522 | unsigned long min; |
54a611b6 LH |
4523 | unsigned long *pivots; |
4524 | struct maple_enode *enode; | |
4525 | int level = 0; | |
39d0bd86 | 4526 | unsigned char node_end; |
54a611b6 LH |
4527 | enum maple_type mt; |
4528 | void __rcu **slots; | |
4529 | ||
4530 | if (mas->max >= max) | |
4531 | goto no_entry; | |
4532 | ||
fff4a58c | 4533 | min = mas->max + 1; |
54a611b6 LH |
4534 | level = 0; |
4535 | do { | |
4536 | if (ma_is_root(node)) | |
4537 | goto no_entry; | |
4538 | ||
fff4a58c | 4539 | /* Walk up. */ |
54a611b6 LH |
4540 | if (unlikely(mas_ascend(mas))) |
4541 | return 1; | |
4542 | ||
54a611b6 LH |
4543 | level++; |
4544 | node = mas_mn(mas); | |
4545 | mt = mte_node_type(mas->node); | |
4546 | pivots = ma_pivots(node, mt); | |
39d0bd86 LH |
4547 | node_end = ma_data_end(node, mt, pivots, mas->max); |
4548 | if (unlikely(ma_dead_node(node))) | |
4549 | return 1; | |
4550 | ||
fff4a58c | 4551 | } while (unlikely(mas->offset == node_end)); |
54a611b6 LH |
4552 | |
4553 | slots = ma_slots(node, mt); | |
fff4a58c LH |
4554 | mas->offset++; |
4555 | enode = mas_slot(mas, slots, mas->offset); | |
4556 | if (unlikely(ma_dead_node(node))) | |
4557 | return 1; | |
54a611b6 | 4558 | |
fff4a58c LH |
4559 | if (level > 1) |
4560 | mas->offset = 0; | |
4561 | ||
4562 | while (unlikely(level > 1)) { | |
54a611b6 | 4563 | level--; |
fff4a58c | 4564 | mas->node = enode; |
54a611b6 LH |
4565 | node = mas_mn(mas); |
4566 | mt = mte_node_type(mas->node); | |
4567 | slots = ma_slots(node, mt); | |
fff4a58c | 4568 | enode = mas_slot(mas, slots, 0); |
39d0bd86 LH |
4569 | if (unlikely(ma_dead_node(node))) |
4570 | return 1; | |
54a611b6 LH |
4571 | } |
4572 | ||
fff4a58c LH |
4573 | if (!mas->offset) |
4574 | pivots = ma_pivots(node, mt); | |
4575 | ||
4576 | mas->max = mas_safe_pivot(mas, pivots, mas->offset, mt); | |
54a611b6 LH |
4577 | if (unlikely(ma_dead_node(node))) |
4578 | return 1; | |
4579 | ||
4580 | mas->node = enode; | |
4581 | mas->min = min; | |
54a611b6 LH |
4582 | return 0; |
4583 | ||
4584 | no_entry: | |
4585 | if (unlikely(ma_dead_node(node))) | |
4586 | return 1; | |
4587 | ||
4588 | mas->node = MAS_NONE; | |
4589 | return 0; | |
4590 | } | |
4591 | ||
4592 | /* | |
fff4a58c | 4593 | * mas_next_slot() - Get the entry in the next slot |
54a611b6 | 4594 | * |
fff4a58c LH |
4595 | * @mas: The maple state |
4596 | * @max: The maximum starting range | |
4597 | * @empty: Can be empty | |
a8091f03 LH |
4598 | * @set_overflow: Should @mas->node be set to overflow when the limit is |
4599 | * reached. | |
54a611b6 | 4600 | * |
fff4a58c | 4601 | * Return: The entry in the next slot which is possibly NULL |
54a611b6 | 4602 | */ |
a8091f03 LH |
4603 | static void *mas_next_slot(struct ma_state *mas, unsigned long max, bool empty, |
4604 | bool set_overflow) | |
54a611b6 | 4605 | { |
54a611b6 | 4606 | void __rcu **slots; |
fff4a58c LH |
4607 | unsigned long *pivots; |
4608 | unsigned long pivot; | |
4609 | enum maple_type type; | |
4610 | struct maple_node *node; | |
4611 | unsigned char data_end; | |
4612 | unsigned long save_point = mas->last; | |
54a611b6 LH |
4613 | void *entry; |
4614 | ||
fff4a58c LH |
4615 | retry: |
4616 | node = mas_mn(mas); | |
4617 | type = mte_node_type(mas->node); | |
39d0bd86 | 4618 | pivots = ma_pivots(node, type); |
fff4a58c LH |
4619 | data_end = ma_data_end(node, type, pivots, mas->max); |
4620 | if (unlikely(mas_rewalk_if_dead(mas, node, save_point))) | |
4621 | goto retry; | |
54a611b6 | 4622 | |
fff4a58c LH |
4623 | if (mas->max >= max) { |
4624 | if (likely(mas->offset < data_end)) | |
4625 | pivot = pivots[mas->offset]; | |
4626 | else | |
a8091f03 | 4627 | goto overflow; |
54a611b6 | 4628 | |
fff4a58c LH |
4629 | if (unlikely(mas_rewalk_if_dead(mas, node, save_point))) |
4630 | goto retry; | |
54a611b6 LH |
4631 | |
4632 | if (pivot >= max) | |
a8091f03 | 4633 | goto overflow; |
fff4a58c | 4634 | } |
54a611b6 | 4635 | |
fff4a58c LH |
4636 | if (likely(mas->offset < data_end)) { |
4637 | mas->index = pivots[mas->offset] + 1; | |
a8091f03 | 4638 | again: |
fff4a58c LH |
4639 | mas->offset++; |
4640 | if (likely(mas->offset < data_end)) | |
4641 | mas->last = pivots[mas->offset]; | |
4642 | else | |
4643 | mas->last = mas->max; | |
4644 | } else { | |
4645 | if (mas_next_node(mas, node, max)) { | |
4646 | mas_rewalk(mas, save_point); | |
4647 | goto retry; | |
4648 | } | |
4649 | ||
a8091f03 LH |
4650 | if (WARN_ON_ONCE(mas_is_none(mas))) { |
4651 | mas->node = MAS_OVERFLOW; | |
ca80f610 | 4652 | return NULL; |
a8091f03 LH |
4653 | goto overflow; |
4654 | } | |
ca80f610 | 4655 | |
fff4a58c LH |
4656 | mas->offset = 0; |
4657 | mas->index = mas->min; | |
4658 | node = mas_mn(mas); | |
4659 | type = mte_node_type(mas->node); | |
4660 | pivots = ma_pivots(node, type); | |
4661 | mas->last = pivots[0]; | |
54a611b6 LH |
4662 | } |
4663 | ||
fff4a58c LH |
4664 | slots = ma_slots(node, type); |
4665 | entry = mt_slot(mas->tree, slots, mas->offset); | |
4666 | if (unlikely(mas_rewalk_if_dead(mas, node, save_point))) | |
4667 | goto retry; | |
54a611b6 | 4668 | |
fff4a58c LH |
4669 | if (entry) |
4670 | return entry; | |
54a611b6 | 4671 | |
fff4a58c | 4672 | if (!empty) { |
a8091f03 LH |
4673 | if (mas->last >= max) |
4674 | goto overflow; | |
4675 | ||
4676 | mas->index = mas->last + 1; | |
4677 | /* Node cannot end on NULL, so it's safe to short-cut here */ | |
fff4a58c LH |
4678 | goto again; |
4679 | } | |
4680 | ||
4681 | return entry; | |
a8091f03 LH |
4682 | |
4683 | overflow: | |
4684 | if (set_overflow) | |
4685 | mas->node = MAS_OVERFLOW; | |
4686 | return NULL; | |
54a611b6 LH |
4687 | } |
4688 | ||
4689 | /* | |
4690 | * mas_next_entry() - Internal function to get the next entry. | |
4691 | * @mas: The maple state | |
4692 | * @limit: The maximum range start. | |
4693 | * | |
4694 | * Set the @mas->node to the next entry and the range_start to | |
4695 | * the beginning value for the entry. Does not check beyond @limit. | |
a8091f03 LH |
4696 | * Sets @mas->index and @mas->last to the range, Does not update @mas->index and |
4697 | * @mas->last on overflow. | |
54a611b6 LH |
4698 | * Restarts on dead nodes. |
4699 | * | |
4700 | * Return: the next entry or %NULL. | |
4701 | */ | |
4702 | static inline void *mas_next_entry(struct ma_state *mas, unsigned long limit) | |
4703 | { | |
a8091f03 LH |
4704 | if (mas->last >= limit) { |
4705 | mas->node = MAS_OVERFLOW; | |
50e81c82 | 4706 | return NULL; |
a8091f03 | 4707 | } |
ca80f610 | 4708 | |
a8091f03 | 4709 | return mas_next_slot(mas, limit, false, true); |
54a611b6 LH |
4710 | } |
4711 | ||
54a611b6 LH |
4712 | /* |
4713 | * mas_rev_awalk() - Internal function. Reverse allocation walk. Find the | |
4714 | * highest gap address of a given size in a given node and descend. | |
4715 | * @mas: The maple state | |
4716 | * @size: The needed size. | |
4717 | * | |
4718 | * Return: True if found in a leaf, false otherwise. | |
4719 | * | |
4720 | */ | |
fad8e429 LH |
4721 | static bool mas_rev_awalk(struct ma_state *mas, unsigned long size, |
4722 | unsigned long *gap_min, unsigned long *gap_max) | |
54a611b6 LH |
4723 | { |
4724 | enum maple_type type = mte_node_type(mas->node); | |
4725 | struct maple_node *node = mas_mn(mas); | |
4726 | unsigned long *pivots, *gaps; | |
4727 | void __rcu **slots; | |
4728 | unsigned long gap = 0; | |
7327e811 | 4729 | unsigned long max, min; |
54a611b6 LH |
4730 | unsigned char offset; |
4731 | ||
4732 | if (unlikely(mas_is_err(mas))) | |
4733 | return true; | |
4734 | ||
4735 | if (ma_is_dense(type)) { | |
4736 | /* dense nodes. */ | |
4737 | mas->offset = (unsigned char)(mas->index - mas->min); | |
4738 | return true; | |
4739 | } | |
4740 | ||
4741 | pivots = ma_pivots(node, type); | |
4742 | slots = ma_slots(node, type); | |
4743 | gaps = ma_gaps(node, type); | |
4744 | offset = mas->offset; | |
4745 | min = mas_safe_min(mas, pivots, offset); | |
4746 | /* Skip out of bounds. */ | |
4747 | while (mas->last < min) | |
4748 | min = mas_safe_min(mas, pivots, --offset); | |
4749 | ||
4750 | max = mas_safe_pivot(mas, pivots, offset, type); | |
7327e811 | 4751 | while (mas->index <= max) { |
54a611b6 LH |
4752 | gap = 0; |
4753 | if (gaps) | |
4754 | gap = gaps[offset]; | |
4755 | else if (!mas_slot(mas, slots, offset)) | |
4756 | gap = max - min + 1; | |
4757 | ||
4758 | if (gap) { | |
4759 | if ((size <= gap) && (size <= mas->last - min + 1)) | |
4760 | break; | |
4761 | ||
4762 | if (!gaps) { | |
4763 | /* Skip the next slot, it cannot be a gap. */ | |
4764 | if (offset < 2) | |
4765 | goto ascend; | |
4766 | ||
4767 | offset -= 2; | |
4768 | max = pivots[offset]; | |
4769 | min = mas_safe_min(mas, pivots, offset); | |
4770 | continue; | |
4771 | } | |
4772 | } | |
4773 | ||
4774 | if (!offset) | |
4775 | goto ascend; | |
4776 | ||
4777 | offset--; | |
4778 | max = min - 1; | |
4779 | min = mas_safe_min(mas, pivots, offset); | |
4780 | } | |
4781 | ||
7327e811 LH |
4782 | if (unlikely((mas->index > max) || (size - 1 > max - mas->index))) |
4783 | goto no_space; | |
54a611b6 LH |
4784 | |
4785 | if (unlikely(ma_is_leaf(type))) { | |
4786 | mas->offset = offset; | |
fad8e429 LH |
4787 | *gap_min = min; |
4788 | *gap_max = min + gap - 1; | |
54a611b6 LH |
4789 | return true; |
4790 | } | |
4791 | ||
4792 | /* descend, only happens under lock. */ | |
4793 | mas->node = mas_slot(mas, slots, offset); | |
4794 | mas->min = min; | |
4795 | mas->max = max; | |
4796 | mas->offset = mas_data_end(mas); | |
4797 | return false; | |
4798 | ||
4799 | ascend: | |
7327e811 LH |
4800 | if (!mte_is_root(mas->node)) |
4801 | return false; | |
54a611b6 | 4802 | |
7327e811 LH |
4803 | no_space: |
4804 | mas_set_err(mas, -EBUSY); | |
54a611b6 LH |
4805 | return false; |
4806 | } | |
4807 | ||
4808 | static inline bool mas_anode_descend(struct ma_state *mas, unsigned long size) | |
4809 | { | |
4810 | enum maple_type type = mte_node_type(mas->node); | |
4811 | unsigned long pivot, min, gap = 0; | |
06e8fd99 LH |
4812 | unsigned char offset, data_end; |
4813 | unsigned long *gaps, *pivots; | |
4814 | void __rcu **slots; | |
4815 | struct maple_node *node; | |
54a611b6 LH |
4816 | bool found = false; |
4817 | ||
4818 | if (ma_is_dense(type)) { | |
4819 | mas->offset = (unsigned char)(mas->index - mas->min); | |
4820 | return true; | |
4821 | } | |
4822 | ||
06e8fd99 LH |
4823 | node = mas_mn(mas); |
4824 | pivots = ma_pivots(node, type); | |
4825 | slots = ma_slots(node, type); | |
4826 | gaps = ma_gaps(node, type); | |
54a611b6 | 4827 | offset = mas->offset; |
54a611b6 | 4828 | min = mas_safe_min(mas, pivots, offset); |
06e8fd99 LH |
4829 | data_end = ma_data_end(node, type, pivots, mas->max); |
4830 | for (; offset <= data_end; offset++) { | |
29b2681f | 4831 | pivot = mas_safe_pivot(mas, pivots, offset, type); |
54a611b6 LH |
4832 | |
4833 | /* Not within lower bounds */ | |
4834 | if (mas->index > pivot) | |
4835 | goto next_slot; | |
4836 | ||
4837 | if (gaps) | |
4838 | gap = gaps[offset]; | |
4839 | else if (!mas_slot(mas, slots, offset)) | |
4840 | gap = min(pivot, mas->last) - max(mas->index, min) + 1; | |
4841 | else | |
4842 | goto next_slot; | |
4843 | ||
4844 | if (gap >= size) { | |
4845 | if (ma_is_leaf(type)) { | |
4846 | found = true; | |
4847 | goto done; | |
4848 | } | |
4849 | if (mas->index <= pivot) { | |
4850 | mas->node = mas_slot(mas, slots, offset); | |
4851 | mas->min = min; | |
4852 | mas->max = pivot; | |
4853 | offset = 0; | |
54a611b6 LH |
4854 | break; |
4855 | } | |
4856 | } | |
4857 | next_slot: | |
4858 | min = pivot + 1; | |
4859 | if (mas->last <= pivot) { | |
4860 | mas_set_err(mas, -EBUSY); | |
4861 | return true; | |
4862 | } | |
4863 | } | |
4864 | ||
4865 | if (mte_is_root(mas->node)) | |
4866 | found = true; | |
4867 | done: | |
4868 | mas->offset = offset; | |
4869 | return found; | |
4870 | } | |
4871 | ||
4872 | /** | |
4873 | * mas_walk() - Search for @mas->index in the tree. | |
4874 | * @mas: The maple state. | |
4875 | * | |
4876 | * mas->index and mas->last will be set to the range if there is a value. If | |
4877 | * mas->node is MAS_NONE, reset to MAS_START. | |
4878 | * | |
4879 | * Return: the entry at the location or %NULL. | |
4880 | */ | |
4881 | void *mas_walk(struct ma_state *mas) | |
4882 | { | |
4883 | void *entry; | |
4884 | ||
a8091f03 | 4885 | if (!mas_is_active(mas) || !mas_is_start(mas)) |
6b23a290 | 4886 | mas->node = MAS_START; |
54a611b6 LH |
4887 | retry: |
4888 | entry = mas_state_walk(mas); | |
6b23a290 | 4889 | if (mas_is_start(mas)) { |
54a611b6 | 4890 | goto retry; |
6b23a290 LH |
4891 | } else if (mas_is_none(mas)) { |
4892 | mas->index = 0; | |
4893 | mas->last = ULONG_MAX; | |
4894 | } else if (mas_is_ptr(mas)) { | |
54a611b6 LH |
4895 | if (!mas->index) { |
4896 | mas->last = 0; | |
6b23a290 | 4897 | return entry; |
54a611b6 | 4898 | } |
54a611b6 | 4899 | |
6b23a290 | 4900 | mas->index = 1; |
54a611b6 | 4901 | mas->last = ULONG_MAX; |
6b23a290 LH |
4902 | mas->node = MAS_NONE; |
4903 | return NULL; | |
54a611b6 LH |
4904 | } |
4905 | ||
4906 | return entry; | |
4907 | } | |
120b1162 | 4908 | EXPORT_SYMBOL_GPL(mas_walk); |
54a611b6 LH |
4909 | |
4910 | static inline bool mas_rewind_node(struct ma_state *mas) | |
4911 | { | |
4912 | unsigned char slot; | |
4913 | ||
4914 | do { | |
4915 | if (mte_is_root(mas->node)) { | |
4916 | slot = mas->offset; | |
4917 | if (!slot) | |
4918 | return false; | |
4919 | } else { | |
4920 | mas_ascend(mas); | |
4921 | slot = mas->offset; | |
4922 | } | |
4923 | } while (!slot); | |
4924 | ||
4925 | mas->offset = --slot; | |
4926 | return true; | |
4927 | } | |
4928 | ||
4929 | /* | |
4930 | * mas_skip_node() - Internal function. Skip over a node. | |
4931 | * @mas: The maple state. | |
4932 | * | |
4933 | * Return: true if there is another node, false otherwise. | |
4934 | */ | |
4935 | static inline bool mas_skip_node(struct ma_state *mas) | |
4936 | { | |
0fa99fdf LH |
4937 | if (mas_is_err(mas)) |
4938 | return false; | |
54a611b6 | 4939 | |
54a611b6 LH |
4940 | do { |
4941 | if (mte_is_root(mas->node)) { | |
0fa99fdf | 4942 | if (mas->offset >= mas_data_end(mas)) { |
54a611b6 LH |
4943 | mas_set_err(mas, -EBUSY); |
4944 | return false; | |
4945 | } | |
4946 | } else { | |
4947 | mas_ascend(mas); | |
54a611b6 | 4948 | } |
0fa99fdf | 4949 | } while (mas->offset >= mas_data_end(mas)); |
54a611b6 | 4950 | |
0fa99fdf | 4951 | mas->offset++; |
54a611b6 LH |
4952 | return true; |
4953 | } | |
4954 | ||
4955 | /* | |
4956 | * mas_awalk() - Allocation walk. Search from low address to high, for a gap of | |
4957 | * @size | |
4958 | * @mas: The maple state | |
4959 | * @size: The size of the gap required | |
4960 | * | |
4961 | * Search between @mas->index and @mas->last for a gap of @size. | |
4962 | */ | |
4963 | static inline void mas_awalk(struct ma_state *mas, unsigned long size) | |
4964 | { | |
4965 | struct maple_enode *last = NULL; | |
4966 | ||
4967 | /* | |
4968 | * There are 4 options: | |
4969 | * go to child (descend) | |
4970 | * go back to parent (ascend) | |
4971 | * no gap found. (return, slot == MAPLE_NODE_SLOTS) | |
4972 | * found the gap. (return, slot != MAPLE_NODE_SLOTS) | |
4973 | */ | |
4974 | while (!mas_is_err(mas) && !mas_anode_descend(mas, size)) { | |
4975 | if (last == mas->node) | |
4976 | mas_skip_node(mas); | |
4977 | else | |
4978 | last = mas->node; | |
4979 | } | |
4980 | } | |
4981 | ||
54a611b6 LH |
4982 | /* |
4983 | * mas_sparse_area() - Internal function. Return upper or lower limit when | |
4984 | * searching for a gap in an empty tree. | |
4985 | * @mas: The maple state | |
4986 | * @min: the minimum range | |
4987 | * @max: The maximum range | |
4988 | * @size: The size of the gap | |
4989 | * @fwd: Searching forward or back | |
4990 | */ | |
29ad6bb3 | 4991 | static inline int mas_sparse_area(struct ma_state *mas, unsigned long min, |
54a611b6 LH |
4992 | unsigned long max, unsigned long size, bool fwd) |
4993 | { | |
29ad6bb3 PZ |
4994 | if (!unlikely(mas_is_none(mas)) && min == 0) { |
4995 | min++; | |
4996 | /* | |
4997 | * At this time, min is increased, we need to recheck whether | |
4998 | * the size is satisfied. | |
4999 | */ | |
5000 | if (min > max || max - min + 1 < size) | |
5001 | return -EBUSY; | |
5002 | } | |
54a611b6 LH |
5003 | /* mas_is_ptr */ |
5004 | ||
54a611b6 | 5005 | if (fwd) { |
29ad6bb3 PZ |
5006 | mas->index = min; |
5007 | mas->last = min + size - 1; | |
5008 | } else { | |
5009 | mas->last = max; | |
5010 | mas->index = max - size + 1; | |
54a611b6 | 5011 | } |
29ad6bb3 | 5012 | return 0; |
54a611b6 LH |
5013 | } |
5014 | ||
5015 | /* | |
5016 | * mas_empty_area() - Get the lowest address within the range that is | |
5017 | * sufficient for the size requested. | |
5018 | * @mas: The maple state | |
5019 | * @min: The lowest value of the range | |
5020 | * @max: The highest value of the range | |
5021 | * @size: The size needed | |
5022 | */ | |
5023 | int mas_empty_area(struct ma_state *mas, unsigned long min, | |
5024 | unsigned long max, unsigned long size) | |
5025 | { | |
5026 | unsigned char offset; | |
5027 | unsigned long *pivots; | |
5028 | enum maple_type mt; | |
5029 | ||
ba997212 LH |
5030 | if (min > max) |
5031 | return -EINVAL; | |
5032 | ||
5033 | if (size == 0 || max - min < size - 1) | |
fad8e429 LH |
5034 | return -EINVAL; |
5035 | ||
54a611b6 LH |
5036 | if (mas_is_start(mas)) |
5037 | mas_start(mas); | |
5038 | else if (mas->offset >= 2) | |
5039 | mas->offset -= 2; | |
5040 | else if (!mas_skip_node(mas)) | |
5041 | return -EBUSY; | |
5042 | ||
5043 | /* Empty set */ | |
29ad6bb3 PZ |
5044 | if (mas_is_none(mas) || mas_is_ptr(mas)) |
5045 | return mas_sparse_area(mas, min, max, size, true); | |
54a611b6 LH |
5046 | |
5047 | /* The start of the window can only be within these values */ | |
5048 | mas->index = min; | |
5049 | mas->last = max; | |
5050 | mas_awalk(mas, size); | |
5051 | ||
5052 | if (unlikely(mas_is_err(mas))) | |
5053 | return xa_err(mas->node); | |
5054 | ||
5055 | offset = mas->offset; | |
5056 | if (unlikely(offset == MAPLE_NODE_SLOTS)) | |
5057 | return -EBUSY; | |
5058 | ||
5059 | mt = mte_node_type(mas->node); | |
5060 | pivots = ma_pivots(mas_mn(mas), mt); | |
0257d990 PZ |
5061 | min = mas_safe_min(mas, pivots, offset); |
5062 | if (mas->index < min) | |
5063 | mas->index = min; | |
54a611b6 LH |
5064 | mas->last = mas->index + size - 1; |
5065 | return 0; | |
5066 | } | |
120b1162 | 5067 | EXPORT_SYMBOL_GPL(mas_empty_area); |
54a611b6 LH |
5068 | |
5069 | /* | |
5070 | * mas_empty_area_rev() - Get the highest address within the range that is | |
5071 | * sufficient for the size requested. | |
5072 | * @mas: The maple state | |
5073 | * @min: The lowest value of the range | |
5074 | * @max: The highest value of the range | |
5075 | * @size: The size needed | |
5076 | */ | |
5077 | int mas_empty_area_rev(struct ma_state *mas, unsigned long min, | |
5078 | unsigned long max, unsigned long size) | |
5079 | { | |
5080 | struct maple_enode *last = mas->node; | |
5081 | ||
ba997212 LH |
5082 | if (min > max) |
5083 | return -EINVAL; | |
5084 | ||
5085 | if (size == 0 || max - min < size - 1) | |
fad8e429 LH |
5086 | return -EINVAL; |
5087 | ||
54a611b6 LH |
5088 | if (mas_is_start(mas)) { |
5089 | mas_start(mas); | |
5090 | mas->offset = mas_data_end(mas); | |
5091 | } else if (mas->offset >= 2) { | |
5092 | mas->offset -= 2; | |
5093 | } else if (!mas_rewind_node(mas)) { | |
5094 | return -EBUSY; | |
5095 | } | |
5096 | ||
5097 | /* Empty set. */ | |
29ad6bb3 PZ |
5098 | if (mas_is_none(mas) || mas_is_ptr(mas)) |
5099 | return mas_sparse_area(mas, min, max, size, false); | |
54a611b6 LH |
5100 | |
5101 | /* The start of the window can only be within these values. */ | |
5102 | mas->index = min; | |
5103 | mas->last = max; | |
5104 | ||
fad8e429 | 5105 | while (!mas_rev_awalk(mas, size, &min, &max)) { |
54a611b6 LH |
5106 | if (last == mas->node) { |
5107 | if (!mas_rewind_node(mas)) | |
5108 | return -EBUSY; | |
5109 | } else { | |
5110 | last = mas->node; | |
5111 | } | |
5112 | } | |
5113 | ||
5114 | if (mas_is_err(mas)) | |
5115 | return xa_err(mas->node); | |
5116 | ||
5117 | if (unlikely(mas->offset == MAPLE_NODE_SLOTS)) | |
5118 | return -EBUSY; | |
5119 | ||
54a611b6 | 5120 | /* Trim the upper limit to the max. */ |
ba997212 | 5121 | if (max < mas->last) |
fad8e429 | 5122 | mas->last = max; |
54a611b6 LH |
5123 | |
5124 | mas->index = mas->last - size + 1; | |
5125 | return 0; | |
5126 | } | |
120b1162 | 5127 | EXPORT_SYMBOL_GPL(mas_empty_area_rev); |
54a611b6 | 5128 | |
54a611b6 | 5129 | /* |
790e1fa8 | 5130 | * mte_dead_leaves() - Mark all leaves of a node as dead. |
54a611b6 LH |
5131 | * @mas: The maple state |
5132 | * @slots: Pointer to the slot array | |
2e5b4921 | 5133 | * @type: The maple node type |
54a611b6 LH |
5134 | * |
5135 | * Must hold the write lock. | |
5136 | * | |
5137 | * Return: The number of leaves marked as dead. | |
5138 | */ | |
5139 | static inline | |
790e1fa8 LH |
5140 | unsigned char mte_dead_leaves(struct maple_enode *enode, struct maple_tree *mt, |
5141 | void __rcu **slots) | |
54a611b6 LH |
5142 | { |
5143 | struct maple_node *node; | |
5144 | enum maple_type type; | |
5145 | void *entry; | |
5146 | int offset; | |
5147 | ||
790e1fa8 LH |
5148 | for (offset = 0; offset < mt_slot_count(enode); offset++) { |
5149 | entry = mt_slot(mt, slots, offset); | |
54a611b6 LH |
5150 | type = mte_node_type(entry); |
5151 | node = mte_to_node(entry); | |
5152 | /* Use both node and type to catch LE & BE metadata */ | |
5153 | if (!node || !type) | |
5154 | break; | |
5155 | ||
5156 | mte_set_node_dead(entry); | |
54a611b6 LH |
5157 | node->type = type; |
5158 | rcu_assign_pointer(slots[offset], node); | |
5159 | } | |
5160 | ||
5161 | return offset; | |
5162 | } | |
5163 | ||
790e1fa8 LH |
5164 | /** |
5165 | * mte_dead_walk() - Walk down a dead tree to just before the leaves | |
5166 | * @enode: The maple encoded node | |
5167 | * @offset: The starting offset | |
5168 | * | |
5169 | * Note: This can only be used from the RCU callback context. | |
5170 | */ | |
5171 | static void __rcu **mte_dead_walk(struct maple_enode **enode, unsigned char offset) | |
54a611b6 LH |
5172 | { |
5173 | struct maple_node *node, *next; | |
5174 | void __rcu **slots = NULL; | |
5175 | ||
790e1fa8 | 5176 | next = mte_to_node(*enode); |
54a611b6 | 5177 | do { |
790e1fa8 LH |
5178 | *enode = ma_enode_ptr(next); |
5179 | node = mte_to_node(*enode); | |
54a611b6 | 5180 | slots = ma_slots(node, node->type); |
790e1fa8 LH |
5181 | next = rcu_dereference_protected(slots[offset], |
5182 | lock_is_held(&rcu_callback_map)); | |
54a611b6 LH |
5183 | offset = 0; |
5184 | } while (!ma_is_leaf(next->type)); | |
5185 | ||
5186 | return slots; | |
5187 | } | |
5188 | ||
790e1fa8 LH |
5189 | /** |
5190 | * mt_free_walk() - Walk & free a tree in the RCU callback context | |
5191 | * @head: The RCU head that's within the node. | |
5192 | * | |
5193 | * Note: This can only be used from the RCU callback context. | |
5194 | */ | |
54a611b6 LH |
5195 | static void mt_free_walk(struct rcu_head *head) |
5196 | { | |
5197 | void __rcu **slots; | |
5198 | struct maple_node *node, *start; | |
790e1fa8 | 5199 | struct maple_enode *enode; |
54a611b6 LH |
5200 | unsigned char offset; |
5201 | enum maple_type type; | |
54a611b6 LH |
5202 | |
5203 | node = container_of(head, struct maple_node, rcu); | |
5204 | ||
5205 | if (ma_is_leaf(node->type)) | |
5206 | goto free_leaf; | |
5207 | ||
54a611b6 | 5208 | start = node; |
790e1fa8 LH |
5209 | enode = mt_mk_node(node, node->type); |
5210 | slots = mte_dead_walk(&enode, 0); | |
5211 | node = mte_to_node(enode); | |
54a611b6 LH |
5212 | do { |
5213 | mt_free_bulk(node->slot_len, slots); | |
5214 | offset = node->parent_slot + 1; | |
790e1fa8 LH |
5215 | enode = node->piv_parent; |
5216 | if (mte_to_node(enode) == node) | |
5217 | goto free_leaf; | |
5218 | ||
5219 | type = mte_node_type(enode); | |
5220 | slots = ma_slots(mte_to_node(enode), type); | |
5221 | if ((offset < mt_slots[type]) && | |
5222 | rcu_dereference_protected(slots[offset], | |
5223 | lock_is_held(&rcu_callback_map))) | |
5224 | slots = mte_dead_walk(&enode, offset); | |
5225 | node = mte_to_node(enode); | |
54a611b6 LH |
5226 | } while ((node != start) || (node->slot_len < offset)); |
5227 | ||
5228 | slots = ma_slots(node, node->type); | |
5229 | mt_free_bulk(node->slot_len, slots); | |
5230 | ||
54a611b6 LH |
5231 | free_leaf: |
5232 | mt_free_rcu(&node->rcu); | |
5233 | } | |
5234 | ||
790e1fa8 LH |
5235 | static inline void __rcu **mte_destroy_descend(struct maple_enode **enode, |
5236 | struct maple_tree *mt, struct maple_enode *prev, unsigned char offset) | |
54a611b6 LH |
5237 | { |
5238 | struct maple_node *node; | |
790e1fa8 | 5239 | struct maple_enode *next = *enode; |
54a611b6 | 5240 | void __rcu **slots = NULL; |
790e1fa8 LH |
5241 | enum maple_type type; |
5242 | unsigned char next_offset = 0; | |
54a611b6 LH |
5243 | |
5244 | do { | |
790e1fa8 LH |
5245 | *enode = next; |
5246 | node = mte_to_node(*enode); | |
5247 | type = mte_node_type(*enode); | |
5248 | slots = ma_slots(node, type); | |
5249 | next = mt_slot_locked(mt, slots, next_offset); | |
54a611b6 | 5250 | if ((mte_dead_node(next))) |
790e1fa8 | 5251 | next = mt_slot_locked(mt, slots, ++next_offset); |
54a611b6 | 5252 | |
790e1fa8 LH |
5253 | mte_set_node_dead(*enode); |
5254 | node->type = type; | |
54a611b6 LH |
5255 | node->piv_parent = prev; |
5256 | node->parent_slot = offset; | |
790e1fa8 LH |
5257 | offset = next_offset; |
5258 | next_offset = 0; | |
5259 | prev = *enode; | |
54a611b6 LH |
5260 | } while (!mte_is_leaf(next)); |
5261 | ||
5262 | return slots; | |
5263 | } | |
5264 | ||
790e1fa8 | 5265 | static void mt_destroy_walk(struct maple_enode *enode, struct maple_tree *mt, |
54a611b6 LH |
5266 | bool free) |
5267 | { | |
5268 | void __rcu **slots; | |
5269 | struct maple_node *node = mte_to_node(enode); | |
5270 | struct maple_enode *start; | |
54a611b6 | 5271 | |
2e5b4921 LH |
5272 | if (mte_is_leaf(enode)) { |
5273 | node->type = mte_node_type(enode); | |
54a611b6 | 5274 | goto free_leaf; |
2e5b4921 | 5275 | } |
54a611b6 | 5276 | |
2e5b4921 | 5277 | start = enode; |
790e1fa8 LH |
5278 | slots = mte_destroy_descend(&enode, mt, start, 0); |
5279 | node = mte_to_node(enode); // Updated in the above call. | |
54a611b6 LH |
5280 | do { |
5281 | enum maple_type type; | |
5282 | unsigned char offset; | |
5283 | struct maple_enode *parent, *tmp; | |
5284 | ||
790e1fa8 | 5285 | node->slot_len = mte_dead_leaves(enode, mt, slots); |
54a611b6 LH |
5286 | if (free) |
5287 | mt_free_bulk(node->slot_len, slots); | |
5288 | offset = node->parent_slot + 1; | |
790e1fa8 LH |
5289 | enode = node->piv_parent; |
5290 | if (mte_to_node(enode) == node) | |
5291 | goto free_leaf; | |
54a611b6 | 5292 | |
790e1fa8 LH |
5293 | type = mte_node_type(enode); |
5294 | slots = ma_slots(mte_to_node(enode), type); | |
54a611b6 LH |
5295 | if (offset >= mt_slots[type]) |
5296 | goto next; | |
5297 | ||
790e1fa8 | 5298 | tmp = mt_slot_locked(mt, slots, offset); |
54a611b6 | 5299 | if (mte_node_type(tmp) && mte_to_node(tmp)) { |
790e1fa8 LH |
5300 | parent = enode; |
5301 | enode = tmp; | |
5302 | slots = mte_destroy_descend(&enode, mt, parent, offset); | |
54a611b6 LH |
5303 | } |
5304 | next: | |
790e1fa8 LH |
5305 | node = mte_to_node(enode); |
5306 | } while (start != enode); | |
54a611b6 | 5307 | |
790e1fa8 LH |
5308 | node = mte_to_node(enode); |
5309 | node->slot_len = mte_dead_leaves(enode, mt, slots); | |
54a611b6 LH |
5310 | if (free) |
5311 | mt_free_bulk(node->slot_len, slots); | |
5312 | ||
54a611b6 LH |
5313 | free_leaf: |
5314 | if (free) | |
5315 | mt_free_rcu(&node->rcu); | |
2e5b4921 | 5316 | else |
790e1fa8 | 5317 | mt_clear_meta(mt, node, node->type); |
54a611b6 LH |
5318 | } |
5319 | ||
5320 | /* | |
5321 | * mte_destroy_walk() - Free a tree or sub-tree. | |
f942b0f0 VY |
5322 | * @enode: the encoded maple node (maple_enode) to start |
5323 | * @mt: the tree to free - needed for node types. | |
54a611b6 LH |
5324 | * |
5325 | * Must hold the write lock. | |
5326 | */ | |
5327 | static inline void mte_destroy_walk(struct maple_enode *enode, | |
5328 | struct maple_tree *mt) | |
5329 | { | |
5330 | struct maple_node *node = mte_to_node(enode); | |
5331 | ||
5332 | if (mt_in_rcu(mt)) { | |
790e1fa8 | 5333 | mt_destroy_walk(enode, mt, false); |
54a611b6 LH |
5334 | call_rcu(&node->rcu, mt_free_walk); |
5335 | } else { | |
790e1fa8 | 5336 | mt_destroy_walk(enode, mt, true); |
54a611b6 LH |
5337 | } |
5338 | } | |
5339 | ||
5340 | static void mas_wr_store_setup(struct ma_wr_state *wr_mas) | |
5341 | { | |
a8091f03 LH |
5342 | if (!mas_is_active(wr_mas->mas)) { |
5343 | if (mas_is_start(wr_mas->mas)) | |
5344 | return; | |
fec29364 | 5345 | |
a8091f03 LH |
5346 | if (unlikely(mas_is_paused(wr_mas->mas))) |
5347 | goto reset; | |
1202700c | 5348 | |
a8091f03 LH |
5349 | if (unlikely(mas_is_none(wr_mas->mas))) |
5350 | goto reset; | |
5351 | ||
5352 | if (unlikely(mas_is_overflow(wr_mas->mas))) | |
5353 | goto reset; | |
5354 | ||
5355 | if (unlikely(mas_is_underflow(wr_mas->mas))) | |
5356 | goto reset; | |
5357 | } | |
fec29364 LH |
5358 | |
5359 | /* | |
5360 | * A less strict version of mas_is_span_wr() where we allow spanning | |
5361 | * writes within this node. This is to stop partial walks in | |
5362 | * mas_prealloc() from being reset. | |
5363 | */ | |
5364 | if (wr_mas->mas->last > wr_mas->mas->max) | |
5365 | goto reset; | |
5366 | ||
5367 | if (wr_mas->entry) | |
5368 | return; | |
5369 | ||
5370 | if (mte_is_leaf(wr_mas->mas->node) && | |
5371 | wr_mas->mas->last == wr_mas->mas->max) | |
5372 | goto reset; | |
5373 | ||
5374 | return; | |
5375 | ||
5376 | reset: | |
5377 | mas_reset(wr_mas->mas); | |
54a611b6 LH |
5378 | } |
5379 | ||
5380 | /* Interface */ | |
5381 | ||
5382 | /** | |
5383 | * mas_store() - Store an @entry. | |
5384 | * @mas: The maple state. | |
5385 | * @entry: The entry to store. | |
5386 | * | |
5387 | * The @mas->index and @mas->last is used to set the range for the @entry. | |
5388 | * Note: The @mas should have pre-allocated entries to ensure there is memory to | |
5389 | * store the entry. Please see mas_expected_entries()/mas_destroy() for more details. | |
5390 | * | |
5391 | * Return: the first entry between mas->index and mas->last or %NULL. | |
5392 | */ | |
5393 | void *mas_store(struct ma_state *mas, void *entry) | |
5394 | { | |
5395 | MA_WR_STATE(wr_mas, mas, entry); | |
5396 | ||
5397 | trace_ma_write(__func__, mas, 0, entry); | |
5398 | #ifdef CONFIG_DEBUG_MAPLE_TREE | |
e6d6792a | 5399 | if (MAS_WARN_ON(mas, mas->index > mas->last)) |
89f499f3 | 5400 | pr_err("Error %lX > %lX %p\n", mas->index, mas->last, entry); |
e6d6792a | 5401 | |
54a611b6 LH |
5402 | if (mas->index > mas->last) { |
5403 | mas_set_err(mas, -EINVAL); | |
5404 | return NULL; | |
5405 | } | |
5406 | ||
5407 | #endif | |
5408 | ||
5409 | /* | |
5410 | * Storing is the same operation as insert with the added caveat that it | |
5411 | * can overwrite entries. Although this seems simple enough, one may | |
5412 | * want to examine what happens if a single store operation was to | |
5413 | * overwrite multiple entries within a self-balancing B-Tree. | |
5414 | */ | |
5415 | mas_wr_store_setup(&wr_mas); | |
5416 | mas_wr_store_entry(&wr_mas); | |
5417 | return wr_mas.content; | |
5418 | } | |
120b1162 | 5419 | EXPORT_SYMBOL_GPL(mas_store); |
54a611b6 LH |
5420 | |
5421 | /** | |
5422 | * mas_store_gfp() - Store a value into the tree. | |
5423 | * @mas: The maple state | |
5424 | * @entry: The entry to store | |
5425 | * @gfp: The GFP_FLAGS to use for allocations if necessary. | |
5426 | * | |
5427 | * Return: 0 on success, -EINVAL on invalid request, -ENOMEM if memory could not | |
5428 | * be allocated. | |
5429 | */ | |
5430 | int mas_store_gfp(struct ma_state *mas, void *entry, gfp_t gfp) | |
5431 | { | |
5432 | MA_WR_STATE(wr_mas, mas, entry); | |
5433 | ||
5434 | mas_wr_store_setup(&wr_mas); | |
5435 | trace_ma_write(__func__, mas, 0, entry); | |
5436 | retry: | |
5437 | mas_wr_store_entry(&wr_mas); | |
5438 | if (unlikely(mas_nomem(mas, gfp))) | |
5439 | goto retry; | |
5440 | ||
5441 | if (unlikely(mas_is_err(mas))) | |
5442 | return xa_err(mas->node); | |
5443 | ||
5444 | return 0; | |
5445 | } | |
120b1162 | 5446 | EXPORT_SYMBOL_GPL(mas_store_gfp); |
54a611b6 LH |
5447 | |
5448 | /** | |
5449 | * mas_store_prealloc() - Store a value into the tree using memory | |
5450 | * preallocated in the maple state. | |
5451 | * @mas: The maple state | |
5452 | * @entry: The entry to store. | |
5453 | */ | |
5454 | void mas_store_prealloc(struct ma_state *mas, void *entry) | |
5455 | { | |
5456 | MA_WR_STATE(wr_mas, mas, entry); | |
5457 | ||
5458 | mas_wr_store_setup(&wr_mas); | |
5459 | trace_ma_write(__func__, mas, 0, entry); | |
5460 | mas_wr_store_entry(&wr_mas); | |
1c414c6a | 5461 | MAS_WR_BUG_ON(&wr_mas, mas_is_err(mas)); |
54a611b6 LH |
5462 | mas_destroy(mas); |
5463 | } | |
120b1162 | 5464 | EXPORT_SYMBOL_GPL(mas_store_prealloc); |
54a611b6 LH |
5465 | |
5466 | /** | |
5467 | * mas_preallocate() - Preallocate enough nodes for a store operation | |
5468 | * @mas: The maple state | |
da089254 | 5469 | * @entry: The entry that will be stored |
54a611b6 LH |
5470 | * @gfp: The GFP_FLAGS to use for allocations. |
5471 | * | |
5472 | * Return: 0 on success, -ENOMEM if memory could not be allocated. | |
5473 | */ | |
da089254 | 5474 | int mas_preallocate(struct ma_state *mas, void *entry, gfp_t gfp) |
54a611b6 | 5475 | { |
17983dc6 LH |
5476 | MA_WR_STATE(wr_mas, mas, entry); |
5477 | unsigned char node_size; | |
5478 | int request = 1; | |
54a611b6 LH |
5479 | int ret; |
5480 | ||
17983dc6 LH |
5481 | |
5482 | if (unlikely(!mas->index && mas->last == ULONG_MAX)) | |
5483 | goto ask_now; | |
5484 | ||
5485 | mas_wr_store_setup(&wr_mas); | |
5486 | wr_mas.content = mas_start(mas); | |
5487 | /* Root expand */ | |
5488 | if (unlikely(mas_is_none(mas) || mas_is_ptr(mas))) | |
5489 | goto ask_now; | |
5490 | ||
5491 | if (unlikely(!mas_wr_walk(&wr_mas))) { | |
5492 | /* Spanning store, use worst case for now */ | |
5493 | request = 1 + mas_mt_height(mas) * 3; | |
5494 | goto ask_now; | |
5495 | } | |
5496 | ||
5497 | /* At this point, we are at the leaf node that needs to be altered. */ | |
5498 | /* Exact fit, no nodes needed. */ | |
5499 | if (wr_mas.r_min == mas->index && wr_mas.r_max == mas->last) | |
5500 | return 0; | |
5501 | ||
5502 | mas_wr_end_piv(&wr_mas); | |
5503 | node_size = mas_wr_new_end(&wr_mas); | |
4249f13c SK |
5504 | |
5505 | /* Slot store, does not require additional nodes */ | |
5506 | if (node_size == wr_mas.node_end) { | |
5507 | /* reuse node */ | |
5508 | if (!mt_in_rcu(mas->tree)) | |
5509 | return 0; | |
5510 | /* shifting boundary */ | |
5511 | if (wr_mas.offset_end - mas->offset == 1) | |
5512 | return 0; | |
5513 | } | |
5514 | ||
17983dc6 LH |
5515 | if (node_size >= mt_slots[wr_mas.type]) { |
5516 | /* Split, worst case for now. */ | |
5517 | request = 1 + mas_mt_height(mas) * 2; | |
5518 | goto ask_now; | |
5519 | } | |
5520 | ||
5521 | /* New root needs a singe node */ | |
5522 | if (unlikely(mte_is_root(mas->node))) | |
5523 | goto ask_now; | |
5524 | ||
5525 | /* Potential spanning rebalance collapsing a node, use worst-case */ | |
5526 | if (node_size - 1 <= mt_min_slots[wr_mas.type]) | |
5527 | request = mas_mt_height(mas) * 2 - 1; | |
5528 | ||
5529 | /* node store, slot store needs one node */ | |
5530 | ask_now: | |
5531 | mas_node_count_gfp(mas, request, gfp); | |
54a611b6 LH |
5532 | mas->mas_flags |= MA_STATE_PREALLOC; |
5533 | if (likely(!mas_is_err(mas))) | |
5534 | return 0; | |
5535 | ||
5536 | mas_set_alloc_req(mas, 0); | |
5537 | ret = xa_err(mas->node); | |
5538 | mas_reset(mas); | |
5539 | mas_destroy(mas); | |
5540 | mas_reset(mas); | |
5541 | return ret; | |
5542 | } | |
5c63a7c3 | 5543 | EXPORT_SYMBOL_GPL(mas_preallocate); |
54a611b6 LH |
5544 | |
5545 | /* | |
5546 | * mas_destroy() - destroy a maple state. | |
5547 | * @mas: The maple state | |
5548 | * | |
5549 | * Upon completion, check the left-most node and rebalance against the node to | |
5550 | * the right if necessary. Frees any allocated nodes associated with this maple | |
5551 | * state. | |
5552 | */ | |
5553 | void mas_destroy(struct ma_state *mas) | |
5554 | { | |
5555 | struct maple_alloc *node; | |
541e06b7 | 5556 | unsigned long total; |
54a611b6 LH |
5557 | |
5558 | /* | |
5559 | * When using mas_for_each() to insert an expected number of elements, | |
5560 | * it is possible that the number inserted is less than the expected | |
5561 | * number. To fix an invalid final node, a check is performed here to | |
5562 | * rebalance the previous node with the final node. | |
5563 | */ | |
5564 | if (mas->mas_flags & MA_STATE_REBALANCE) { | |
5565 | unsigned char end; | |
5566 | ||
23e734ec | 5567 | mas_start(mas); |
54a611b6 LH |
5568 | mtree_range_walk(mas); |
5569 | end = mas_data_end(mas) + 1; | |
5570 | if (end < mt_min_slot_count(mas->node) - 1) | |
5571 | mas_destroy_rebalance(mas, end); | |
5572 | ||
5573 | mas->mas_flags &= ~MA_STATE_REBALANCE; | |
5574 | } | |
5575 | mas->mas_flags &= ~(MA_STATE_BULK|MA_STATE_PREALLOC); | |
5576 | ||
541e06b7 LH |
5577 | total = mas_allocated(mas); |
5578 | while (total) { | |
54a611b6 LH |
5579 | node = mas->alloc; |
5580 | mas->alloc = node->slot[0]; | |
541e06b7 LH |
5581 | if (node->node_count > 1) { |
5582 | size_t count = node->node_count - 1; | |
5583 | ||
5584 | mt_free_bulk(count, (void __rcu **)&node->slot[1]); | |
5585 | total -= count; | |
5586 | } | |
54a611b6 | 5587 | kmem_cache_free(maple_node_cache, node); |
541e06b7 | 5588 | total--; |
54a611b6 | 5589 | } |
541e06b7 | 5590 | |
54a611b6 LH |
5591 | mas->alloc = NULL; |
5592 | } | |
120b1162 | 5593 | EXPORT_SYMBOL_GPL(mas_destroy); |
54a611b6 LH |
5594 | |
5595 | /* | |
5596 | * mas_expected_entries() - Set the expected number of entries that will be inserted. | |
5597 | * @mas: The maple state | |
5598 | * @nr_entries: The number of expected entries. | |
5599 | * | |
5600 | * This will attempt to pre-allocate enough nodes to store the expected number | |
5601 | * of entries. The allocations will occur using the bulk allocator interface | |
5602 | * for speed. Please call mas_destroy() on the @mas after inserting the entries | |
5603 | * to ensure any unused nodes are freed. | |
5604 | * | |
5605 | * Return: 0 on success, -ENOMEM if memory could not be allocated. | |
5606 | */ | |
5607 | int mas_expected_entries(struct ma_state *mas, unsigned long nr_entries) | |
5608 | { | |
5609 | int nonleaf_cap = MAPLE_ARANGE64_SLOTS - 2; | |
5610 | struct maple_enode *enode = mas->node; | |
5611 | int nr_nodes; | |
5612 | int ret; | |
5613 | ||
5614 | /* | |
5615 | * Sometimes it is necessary to duplicate a tree to a new tree, such as | |
5616 | * forking a process and duplicating the VMAs from one tree to a new | |
5617 | * tree. When such a situation arises, it is known that the new tree is | |
5618 | * not going to be used until the entire tree is populated. For | |
5619 | * performance reasons, it is best to use a bulk load with RCU disabled. | |
5620 | * This allows for optimistic splitting that favours the left and reuse | |
5621 | * of nodes during the operation. | |
5622 | */ | |
5623 | ||
5624 | /* Optimize splitting for bulk insert in-order */ | |
5625 | mas->mas_flags |= MA_STATE_BULK; | |
5626 | ||
5627 | /* | |
5628 | * Avoid overflow, assume a gap between each entry and a trailing null. | |
5629 | * If this is wrong, it just means allocation can happen during | |
5630 | * insertion of entries. | |
5631 | */ | |
5632 | nr_nodes = max(nr_entries, nr_entries * 2 + 1); | |
5633 | if (!mt_is_alloc(mas->tree)) | |
5634 | nonleaf_cap = MAPLE_RANGE64_SLOTS - 2; | |
5635 | ||
5636 | /* Leaves; reduce slots to keep space for expansion */ | |
5637 | nr_nodes = DIV_ROUND_UP(nr_nodes, MAPLE_RANGE64_SLOTS - 2); | |
5638 | /* Internal nodes */ | |
5639 | nr_nodes += DIV_ROUND_UP(nr_nodes, nonleaf_cap); | |
5640 | /* Add working room for split (2 nodes) + new parents */ | |
099d7439 | 5641 | mas_node_count_gfp(mas, nr_nodes + 3, GFP_KERNEL); |
54a611b6 LH |
5642 | |
5643 | /* Detect if allocations run out */ | |
5644 | mas->mas_flags |= MA_STATE_PREALLOC; | |
5645 | ||
5646 | if (!mas_is_err(mas)) | |
5647 | return 0; | |
5648 | ||
5649 | ret = xa_err(mas->node); | |
5650 | mas->node = enode; | |
5651 | mas_destroy(mas); | |
5652 | return ret; | |
5653 | ||
5654 | } | |
120b1162 | 5655 | EXPORT_SYMBOL_GPL(mas_expected_entries); |
54a611b6 | 5656 | |
6169b553 LH |
5657 | static inline bool mas_next_setup(struct ma_state *mas, unsigned long max, |
5658 | void **entry) | |
54a611b6 | 5659 | { |
ca80f610 LH |
5660 | bool was_none = mas_is_none(mas); |
5661 | ||
a8091f03 LH |
5662 | if (unlikely(mas->last >= max)) { |
5663 | mas->node = MAS_OVERFLOW; | |
5664 | return true; | |
5665 | } | |
5666 | ||
5667 | if (mas_is_active(mas)) | |
5668 | return false; | |
5669 | ||
5670 | if (mas_is_none(mas) || mas_is_paused(mas)) { | |
5671 | mas->node = MAS_START; | |
5672 | } else if (mas_is_overflow(mas)) { | |
5673 | /* Overflowed before, but the max changed */ | |
54a611b6 | 5674 | mas->node = MAS_START; |
a8091f03 LH |
5675 | } else if (mas_is_underflow(mas)) { |
5676 | mas->node = MAS_START; | |
5677 | *entry = mas_walk(mas); | |
5678 | if (*entry) | |
5679 | return true; | |
5680 | } | |
54a611b6 LH |
5681 | |
5682 | if (mas_is_start(mas)) | |
6169b553 | 5683 | *entry = mas_walk(mas); /* Retries on dead nodes handled by mas_walk */ |
54a611b6 LH |
5684 | |
5685 | if (mas_is_ptr(mas)) { | |
6169b553 | 5686 | *entry = NULL; |
ca80f610 LH |
5687 | if (was_none && mas->index == 0) { |
5688 | mas->index = mas->last = 0; | |
6169b553 | 5689 | return true; |
54a611b6 | 5690 | } |
ca80f610 LH |
5691 | mas->index = 1; |
5692 | mas->last = ULONG_MAX; | |
5693 | mas->node = MAS_NONE; | |
6169b553 | 5694 | return true; |
54a611b6 LH |
5695 | } |
5696 | ||
6169b553 LH |
5697 | if (mas_is_none(mas)) |
5698 | return true; | |
a8091f03 | 5699 | |
6169b553 LH |
5700 | return false; |
5701 | } | |
5702 | ||
5703 | /** | |
5704 | * mas_next() - Get the next entry. | |
5705 | * @mas: The maple state | |
5706 | * @max: The maximum index to check. | |
5707 | * | |
5708 | * Returns the next entry after @mas->index. | |
5709 | * Must hold rcu_read_lock or the write lock. | |
5710 | * Can return the zero entry. | |
5711 | * | |
5712 | * Return: The next entry or %NULL | |
5713 | */ | |
5714 | void *mas_next(struct ma_state *mas, unsigned long max) | |
5715 | { | |
5716 | void *entry = NULL; | |
5717 | ||
5718 | if (mas_next_setup(mas, max, &entry)) | |
5719 | return entry; | |
5720 | ||
5721 | /* Retries on dead nodes handled by mas_next_slot */ | |
a8091f03 | 5722 | return mas_next_slot(mas, max, false, true); |
54a611b6 LH |
5723 | } |
5724 | EXPORT_SYMBOL_GPL(mas_next); | |
5725 | ||
6169b553 LH |
5726 | /** |
5727 | * mas_next_range() - Advance the maple state to the next range | |
5728 | * @mas: The maple state | |
5729 | * @max: The maximum index to check. | |
5730 | * | |
5731 | * Sets @mas->index and @mas->last to the range. | |
5732 | * Must hold rcu_read_lock or the write lock. | |
5733 | * Can return the zero entry. | |
5734 | * | |
5735 | * Return: The next entry or %NULL | |
5736 | */ | |
5737 | void *mas_next_range(struct ma_state *mas, unsigned long max) | |
5738 | { | |
5739 | void *entry = NULL; | |
5740 | ||
5741 | if (mas_next_setup(mas, max, &entry)) | |
5742 | return entry; | |
5743 | ||
5744 | /* Retries on dead nodes handled by mas_next_slot */ | |
a8091f03 | 5745 | return mas_next_slot(mas, max, true, true); |
6169b553 LH |
5746 | } |
5747 | EXPORT_SYMBOL_GPL(mas_next_range); | |
5748 | ||
54a611b6 LH |
5749 | /** |
5750 | * mt_next() - get the next value in the maple tree | |
5751 | * @mt: The maple tree | |
5752 | * @index: The start index | |
5753 | * @max: The maximum index to check | |
5754 | * | |
fad9c80e TG |
5755 | * Takes RCU read lock internally to protect the search, which does not |
5756 | * protect the returned pointer after dropping RCU read lock. | |
5757 | * See also: Documentation/core-api/maple_tree.rst | |
5758 | * | |
5759 | * Return: The entry higher than @index or %NULL if nothing is found. | |
54a611b6 LH |
5760 | */ |
5761 | void *mt_next(struct maple_tree *mt, unsigned long index, unsigned long max) | |
5762 | { | |
5763 | void *entry = NULL; | |
5764 | MA_STATE(mas, mt, index, index); | |
5765 | ||
5766 | rcu_read_lock(); | |
5767 | entry = mas_next(&mas, max); | |
5768 | rcu_read_unlock(); | |
5769 | return entry; | |
5770 | } | |
5771 | EXPORT_SYMBOL_GPL(mt_next); | |
5772 | ||
6b9e93e0 LH |
5773 | static inline bool mas_prev_setup(struct ma_state *mas, unsigned long min, |
5774 | void **entry) | |
54a611b6 | 5775 | { |
a8091f03 LH |
5776 | if (unlikely(mas->index <= min)) { |
5777 | mas->node = MAS_UNDERFLOW; | |
5778 | return true; | |
5779 | } | |
54a611b6 | 5780 | |
a8091f03 LH |
5781 | if (mas_is_active(mas)) |
5782 | return false; | |
5783 | ||
5784 | if (mas_is_overflow(mas)) { | |
54a611b6 | 5785 | mas->node = MAS_START; |
a8091f03 LH |
5786 | *entry = mas_walk(mas); |
5787 | if (*entry) | |
5788 | return true; | |
5789 | } | |
54a611b6 | 5790 | |
a8091f03 LH |
5791 | if (mas_is_none(mas) || mas_is_paused(mas)) { |
5792 | mas->node = MAS_START; | |
5793 | } else if (mas_is_underflow(mas)) { | |
5794 | /* underflowed before but the min changed */ | |
5795 | mas->node = MAS_START; | |
54a611b6 LH |
5796 | } |
5797 | ||
a8091f03 LH |
5798 | if (mas_is_start(mas)) |
5799 | mas_walk(mas); | |
5800 | ||
39193685 LH |
5801 | if (unlikely(mas_is_ptr(mas))) { |
5802 | if (!mas->index) | |
5803 | goto none; | |
54a611b6 | 5804 | mas->index = mas->last = 0; |
6b9e93e0 LH |
5805 | *entry = mas_root(mas); |
5806 | return true; | |
39193685 LH |
5807 | } |
5808 | ||
5809 | if (mas_is_none(mas)) { | |
5810 | if (mas->index) { | |
5811 | /* Walked to out-of-range pointer? */ | |
5812 | mas->index = mas->last = 0; | |
5813 | mas->node = MAS_ROOT; | |
6b9e93e0 LH |
5814 | *entry = mas_root(mas); |
5815 | return true; | |
39193685 | 5816 | } |
6b9e93e0 | 5817 | return true; |
54a611b6 | 5818 | } |
6b9e93e0 LH |
5819 | |
5820 | return false; | |
39193685 LH |
5821 | |
5822 | none: | |
5823 | mas->node = MAS_NONE; | |
6b9e93e0 LH |
5824 | return true; |
5825 | } | |
5826 | ||
5827 | /** | |
5828 | * mas_prev() - Get the previous entry | |
5829 | * @mas: The maple state | |
5830 | * @min: The minimum value to check. | |
5831 | * | |
5832 | * Must hold rcu_read_lock or the write lock. | |
5833 | * Will reset mas to MAS_START if the node is MAS_NONE. Will stop on not | |
5834 | * searchable nodes. | |
5835 | * | |
5836 | * Return: the previous value or %NULL. | |
5837 | */ | |
5838 | void *mas_prev(struct ma_state *mas, unsigned long min) | |
5839 | { | |
5840 | void *entry = NULL; | |
5841 | ||
5842 | if (mas_prev_setup(mas, min, &entry)) | |
5843 | return entry; | |
5844 | ||
a8091f03 | 5845 | return mas_prev_slot(mas, min, false, true); |
54a611b6 LH |
5846 | } |
5847 | EXPORT_SYMBOL_GPL(mas_prev); | |
5848 | ||
6b9e93e0 LH |
5849 | /** |
5850 | * mas_prev_range() - Advance to the previous range | |
5851 | * @mas: The maple state | |
5852 | * @min: The minimum value to check. | |
5853 | * | |
5854 | * Sets @mas->index and @mas->last to the range. | |
5855 | * Must hold rcu_read_lock or the write lock. | |
5856 | * Will reset mas to MAS_START if the node is MAS_NONE. Will stop on not | |
5857 | * searchable nodes. | |
5858 | * | |
5859 | * Return: the previous value or %NULL. | |
5860 | */ | |
5861 | void *mas_prev_range(struct ma_state *mas, unsigned long min) | |
5862 | { | |
5863 | void *entry = NULL; | |
5864 | ||
5865 | if (mas_prev_setup(mas, min, &entry)) | |
5866 | return entry; | |
5867 | ||
a8091f03 | 5868 | return mas_prev_slot(mas, min, true, true); |
6b9e93e0 LH |
5869 | } |
5870 | EXPORT_SYMBOL_GPL(mas_prev_range); | |
5871 | ||
54a611b6 LH |
5872 | /** |
5873 | * mt_prev() - get the previous value in the maple tree | |
5874 | * @mt: The maple tree | |
5875 | * @index: The start index | |
5876 | * @min: The minimum index to check | |
5877 | * | |
fad9c80e TG |
5878 | * Takes RCU read lock internally to protect the search, which does not |
5879 | * protect the returned pointer after dropping RCU read lock. | |
5880 | * See also: Documentation/core-api/maple_tree.rst | |
5881 | * | |
5882 | * Return: The entry before @index or %NULL if nothing is found. | |
54a611b6 LH |
5883 | */ |
5884 | void *mt_prev(struct maple_tree *mt, unsigned long index, unsigned long min) | |
5885 | { | |
5886 | void *entry = NULL; | |
5887 | MA_STATE(mas, mt, index, index); | |
5888 | ||
5889 | rcu_read_lock(); | |
5890 | entry = mas_prev(&mas, min); | |
5891 | rcu_read_unlock(); | |
5892 | return entry; | |
5893 | } | |
5894 | EXPORT_SYMBOL_GPL(mt_prev); | |
5895 | ||
5896 | /** | |
5897 | * mas_pause() - Pause a mas_find/mas_for_each to drop the lock. | |
5898 | * @mas: The maple state to pause | |
5899 | * | |
5900 | * Some users need to pause a walk and drop the lock they're holding in | |
5901 | * order to yield to a higher priority thread or carry out an operation | |
5902 | * on an entry. Those users should call this function before they drop | |
5903 | * the lock. It resets the @mas to be suitable for the next iteration | |
5904 | * of the loop after the user has reacquired the lock. If most entries | |
5905 | * found during a walk require you to call mas_pause(), the mt_for_each() | |
5906 | * iterator may be more appropriate. | |
5907 | * | |
5908 | */ | |
5909 | void mas_pause(struct ma_state *mas) | |
5910 | { | |
5911 | mas->node = MAS_PAUSE; | |
5912 | } | |
5913 | EXPORT_SYMBOL_GPL(mas_pause); | |
5914 | ||
5915 | /** | |
6169b553 | 5916 | * mas_find_setup() - Internal function to set up mas_find*(). |
54a611b6 | 5917 | * @mas: The maple state |
6169b553 LH |
5918 | * @max: The maximum index |
5919 | * @entry: Pointer to the entry | |
54a611b6 | 5920 | * |
6169b553 | 5921 | * Returns: True if entry is the answer, false otherwise. |
54a611b6 | 5922 | */ |
6169b553 LH |
5923 | static inline bool mas_find_setup(struct ma_state *mas, unsigned long max, |
5924 | void **entry) | |
54a611b6 | 5925 | { |
a8091f03 LH |
5926 | if (mas_is_active(mas)) { |
5927 | if (mas->last < max) | |
5928 | return false; | |
5929 | ||
5930 | return true; | |
5931 | } | |
6169b553 | 5932 | |
a8091f03 | 5933 | if (mas_is_paused(mas)) { |
ca80f610 | 5934 | if (unlikely(mas->last >= max)) |
6169b553 | 5935 | return true; |
ca80f610 | 5936 | |
a8091f03 | 5937 | mas->index = ++mas->last; |
ca80f610 | 5938 | mas->node = MAS_START; |
a8091f03 | 5939 | } else if (mas_is_none(mas)) { |
ca80f610 | 5940 | if (unlikely(mas->last >= max)) |
6169b553 | 5941 | return true; |
ca80f610 | 5942 | |
a8091f03 | 5943 | mas->index = mas->last; |
54a611b6 | 5944 | mas->node = MAS_START; |
a8091f03 LH |
5945 | } else if (mas_is_overflow(mas) || mas_is_underflow(mas)) { |
5946 | if (mas->index > max) { | |
5947 | mas->node = MAS_OVERFLOW; | |
5948 | return true; | |
5949 | } | |
17dc622c | 5950 | |
a8091f03 LH |
5951 | mas->node = MAS_START; |
5952 | } | |
5953 | ||
5954 | if (mas_is_start(mas)) { | |
54a611b6 | 5955 | /* First run or continue */ |
54a611b6 | 5956 | if (mas->index > max) |
6169b553 | 5957 | return true; |
54a611b6 | 5958 | |
6169b553 LH |
5959 | *entry = mas_walk(mas); |
5960 | if (*entry) | |
5961 | return true; | |
ca80f610 | 5962 | |
54a611b6 LH |
5963 | } |
5964 | ||
ca80f610 LH |
5965 | if (unlikely(!mas_searchable(mas))) { |
5966 | if (unlikely(mas_is_ptr(mas))) | |
5967 | goto ptr_out_of_range; | |
5968 | ||
6169b553 | 5969 | return true; |
ca80f610 LH |
5970 | } |
5971 | ||
5972 | if (mas->index == max) | |
6169b553 | 5973 | return true; |
54a611b6 | 5974 | |
6169b553 | 5975 | return false; |
ca80f610 LH |
5976 | |
5977 | ptr_out_of_range: | |
5978 | mas->node = MAS_NONE; | |
5979 | mas->index = 1; | |
5980 | mas->last = ULONG_MAX; | |
6169b553 LH |
5981 | return true; |
5982 | } | |
5983 | ||
5984 | /** | |
5985 | * mas_find() - On the first call, find the entry at or after mas->index up to | |
5986 | * %max. Otherwise, find the entry after mas->index. | |
5987 | * @mas: The maple state | |
5988 | * @max: The maximum value to check. | |
5989 | * | |
5990 | * Must hold rcu_read_lock or the write lock. | |
5991 | * If an entry exists, last and index are updated accordingly. | |
5992 | * May set @mas->node to MAS_NONE. | |
5993 | * | |
5994 | * Return: The entry or %NULL. | |
5995 | */ | |
5996 | void *mas_find(struct ma_state *mas, unsigned long max) | |
5997 | { | |
5998 | void *entry = NULL; | |
5999 | ||
6000 | if (mas_find_setup(mas, max, &entry)) | |
6001 | return entry; | |
6002 | ||
6003 | /* Retries on dead nodes handled by mas_next_slot */ | |
a8091f03 | 6004 | return mas_next_slot(mas, max, false, false); |
54a611b6 | 6005 | } |
120b1162 | 6006 | EXPORT_SYMBOL_GPL(mas_find); |
54a611b6 | 6007 | |
6169b553 LH |
6008 | /** |
6009 | * mas_find_range() - On the first call, find the entry at or after | |
6010 | * mas->index up to %max. Otherwise, advance to the next slot mas->index. | |
6011 | * @mas: The maple state | |
6012 | * @max: The maximum value to check. | |
6013 | * | |
6014 | * Must hold rcu_read_lock or the write lock. | |
6015 | * If an entry exists, last and index are updated accordingly. | |
6016 | * May set @mas->node to MAS_NONE. | |
6017 | * | |
6018 | * Return: The entry or %NULL. | |
6019 | */ | |
6020 | void *mas_find_range(struct ma_state *mas, unsigned long max) | |
6021 | { | |
a8091f03 | 6022 | void *entry = NULL; |
6169b553 LH |
6023 | |
6024 | if (mas_find_setup(mas, max, &entry)) | |
6025 | return entry; | |
6026 | ||
6027 | /* Retries on dead nodes handled by mas_next_slot */ | |
a8091f03 | 6028 | return mas_next_slot(mas, max, true, false); |
6169b553 LH |
6029 | } |
6030 | EXPORT_SYMBOL_GPL(mas_find_range); | |
6031 | ||
54a611b6 | 6032 | /** |
6b9e93e0 | 6033 | * mas_find_rev_setup() - Internal function to set up mas_find_*_rev() |
54a611b6 | 6034 | * @mas: The maple state |
6b9e93e0 LH |
6035 | * @min: The minimum index |
6036 | * @entry: Pointer to the entry | |
54a611b6 | 6037 | * |
6b9e93e0 | 6038 | * Returns: True if entry is the answer, false otherwise. |
54a611b6 | 6039 | */ |
6b9e93e0 LH |
6040 | static inline bool mas_find_rev_setup(struct ma_state *mas, unsigned long min, |
6041 | void **entry) | |
54a611b6 | 6042 | { |
a8091f03 LH |
6043 | if (mas_is_active(mas)) { |
6044 | if (mas->index > min) | |
6045 | return false; | |
39193685 | 6046 | |
a8091f03 | 6047 | return true; |
39193685 LH |
6048 | } |
6049 | ||
a8091f03 | 6050 | if (mas_is_paused(mas)) { |
39193685 | 6051 | if (unlikely(mas->index <= min)) { |
54a611b6 | 6052 | mas->node = MAS_NONE; |
6b9e93e0 | 6053 | return true; |
54a611b6 LH |
6054 | } |
6055 | mas->node = MAS_START; | |
6056 | mas->last = --mas->index; | |
a8091f03 LH |
6057 | } else if (mas_is_none(mas)) { |
6058 | if (mas->index <= min) | |
6059 | goto none; | |
6060 | ||
6061 | mas->last = mas->index; | |
6062 | mas->node = MAS_START; | |
6063 | } else if (mas_is_underflow(mas) || mas_is_overflow(mas)) { | |
6064 | if (mas->last <= min) { | |
6065 | mas->node = MAS_UNDERFLOW; | |
6066 | return true; | |
6067 | } | |
6068 | ||
6069 | mas->node = MAS_START; | |
54a611b6 LH |
6070 | } |
6071 | ||
a8091f03 | 6072 | if (mas_is_start(mas)) { |
54a611b6 | 6073 | /* First run or continue */ |
54a611b6 | 6074 | if (mas->index < min) |
6b9e93e0 | 6075 | return true; |
54a611b6 | 6076 | |
6b9e93e0 LH |
6077 | *entry = mas_walk(mas); |
6078 | if (*entry) | |
6079 | return true; | |
54a611b6 LH |
6080 | } |
6081 | ||
39193685 LH |
6082 | if (unlikely(!mas_searchable(mas))) { |
6083 | if (mas_is_ptr(mas)) | |
6084 | goto none; | |
6085 | ||
6086 | if (mas_is_none(mas)) { | |
6087 | /* | |
6088 | * Walked to the location, and there was nothing so the | |
6089 | * previous location is 0. | |
6090 | */ | |
6091 | mas->last = mas->index = 0; | |
6092 | mas->node = MAS_ROOT; | |
6b9e93e0 LH |
6093 | *entry = mas_root(mas); |
6094 | return true; | |
39193685 LH |
6095 | } |
6096 | } | |
54a611b6 LH |
6097 | |
6098 | if (mas->index < min) | |
6b9e93e0 | 6099 | return true; |
54a611b6 | 6100 | |
6b9e93e0 | 6101 | return false; |
39193685 LH |
6102 | |
6103 | none: | |
6104 | mas->node = MAS_NONE; | |
6b9e93e0 LH |
6105 | return true; |
6106 | } | |
6107 | ||
6108 | /** | |
6109 | * mas_find_rev: On the first call, find the first non-null entry at or below | |
6110 | * mas->index down to %min. Otherwise find the first non-null entry below | |
6111 | * mas->index down to %min. | |
6112 | * @mas: The maple state | |
6113 | * @min: The minimum value to check. | |
6114 | * | |
6115 | * Must hold rcu_read_lock or the write lock. | |
6116 | * If an entry exists, last and index are updated accordingly. | |
6117 | * May set @mas->node to MAS_NONE. | |
6118 | * | |
6119 | * Return: The entry or %NULL. | |
6120 | */ | |
6121 | void *mas_find_rev(struct ma_state *mas, unsigned long min) | |
6122 | { | |
a8091f03 | 6123 | void *entry = NULL; |
6b9e93e0 LH |
6124 | |
6125 | if (mas_find_rev_setup(mas, min, &entry)) | |
6126 | return entry; | |
6127 | ||
6128 | /* Retries on dead nodes handled by mas_prev_slot */ | |
a8091f03 | 6129 | return mas_prev_slot(mas, min, false, false); |
6b9e93e0 | 6130 | |
54a611b6 | 6131 | } |
120b1162 | 6132 | EXPORT_SYMBOL_GPL(mas_find_rev); |
54a611b6 | 6133 | |
6b9e93e0 LH |
6134 | /** |
6135 | * mas_find_range_rev: On the first call, find the first non-null entry at or | |
6136 | * below mas->index down to %min. Otherwise advance to the previous slot after | |
6137 | * mas->index down to %min. | |
6138 | * @mas: The maple state | |
6139 | * @min: The minimum value to check. | |
6140 | * | |
6141 | * Must hold rcu_read_lock or the write lock. | |
6142 | * If an entry exists, last and index are updated accordingly. | |
6143 | * May set @mas->node to MAS_NONE. | |
6144 | * | |
6145 | * Return: The entry or %NULL. | |
6146 | */ | |
6147 | void *mas_find_range_rev(struct ma_state *mas, unsigned long min) | |
6148 | { | |
a8091f03 | 6149 | void *entry = NULL; |
6b9e93e0 LH |
6150 | |
6151 | if (mas_find_rev_setup(mas, min, &entry)) | |
6152 | return entry; | |
6153 | ||
6154 | /* Retries on dead nodes handled by mas_prev_slot */ | |
a8091f03 | 6155 | return mas_prev_slot(mas, min, true, false); |
6b9e93e0 LH |
6156 | } |
6157 | EXPORT_SYMBOL_GPL(mas_find_range_rev); | |
6158 | ||
54a611b6 LH |
6159 | /** |
6160 | * mas_erase() - Find the range in which index resides and erase the entire | |
6161 | * range. | |
6162 | * @mas: The maple state | |
6163 | * | |
6164 | * Must hold the write lock. | |
6165 | * Searches for @mas->index, sets @mas->index and @mas->last to the range and | |
6166 | * erases that range. | |
6167 | * | |
6168 | * Return: the entry that was erased or %NULL, @mas->index and @mas->last are updated. | |
6169 | */ | |
6170 | void *mas_erase(struct ma_state *mas) | |
6171 | { | |
6172 | void *entry; | |
6173 | MA_WR_STATE(wr_mas, mas, NULL); | |
6174 | ||
6175 | if (mas_is_none(mas) || mas_is_paused(mas)) | |
6176 | mas->node = MAS_START; | |
6177 | ||
6178 | /* Retry unnecessary when holding the write lock. */ | |
6179 | entry = mas_state_walk(mas); | |
6180 | if (!entry) | |
6181 | return NULL; | |
6182 | ||
6183 | write_retry: | |
6184 | /* Must reset to ensure spanning writes of last slot are detected */ | |
6185 | mas_reset(mas); | |
6186 | mas_wr_store_setup(&wr_mas); | |
6187 | mas_wr_store_entry(&wr_mas); | |
6188 | if (mas_nomem(mas, GFP_KERNEL)) | |
6189 | goto write_retry; | |
6190 | ||
6191 | return entry; | |
6192 | } | |
6193 | EXPORT_SYMBOL_GPL(mas_erase); | |
6194 | ||
6195 | /** | |
6196 | * mas_nomem() - Check if there was an error allocating and do the allocation | |
6197 | * if necessary If there are allocations, then free them. | |
6198 | * @mas: The maple state | |
6199 | * @gfp: The GFP_FLAGS to use for allocations | |
6200 | * Return: true on allocation, false otherwise. | |
6201 | */ | |
6202 | bool mas_nomem(struct ma_state *mas, gfp_t gfp) | |
14c4b5ab | 6203 | __must_hold(mas->tree->ma_lock) |
54a611b6 LH |
6204 | { |
6205 | if (likely(mas->node != MA_ERROR(-ENOMEM))) { | |
6206 | mas_destroy(mas); | |
6207 | return false; | |
6208 | } | |
6209 | ||
6210 | if (gfpflags_allow_blocking(gfp) && !mt_external_lock(mas->tree)) { | |
6211 | mtree_unlock(mas->tree); | |
6212 | mas_alloc_nodes(mas, gfp); | |
6213 | mtree_lock(mas->tree); | |
6214 | } else { | |
6215 | mas_alloc_nodes(mas, gfp); | |
6216 | } | |
6217 | ||
6218 | if (!mas_allocated(mas)) | |
6219 | return false; | |
6220 | ||
6221 | mas->node = MAS_START; | |
6222 | return true; | |
6223 | } | |
6224 | ||
6225 | void __init maple_tree_init(void) | |
6226 | { | |
6227 | maple_node_cache = kmem_cache_create("maple_node", | |
6228 | sizeof(struct maple_node), sizeof(struct maple_node), | |
6229 | SLAB_PANIC, NULL); | |
6230 | } | |
6231 | ||
6232 | /** | |
6233 | * mtree_load() - Load a value stored in a maple tree | |
6234 | * @mt: The maple tree | |
6235 | * @index: The index to load | |
6236 | * | |
6237 | * Return: the entry or %NULL | |
6238 | */ | |
6239 | void *mtree_load(struct maple_tree *mt, unsigned long index) | |
6240 | { | |
6241 | MA_STATE(mas, mt, index, index); | |
6242 | void *entry; | |
6243 | ||
6244 | trace_ma_read(__func__, &mas); | |
6245 | rcu_read_lock(); | |
6246 | retry: | |
6247 | entry = mas_start(&mas); | |
6248 | if (unlikely(mas_is_none(&mas))) | |
6249 | goto unlock; | |
6250 | ||
6251 | if (unlikely(mas_is_ptr(&mas))) { | |
6252 | if (index) | |
6253 | entry = NULL; | |
6254 | ||
6255 | goto unlock; | |
6256 | } | |
6257 | ||
6258 | entry = mtree_lookup_walk(&mas); | |
6259 | if (!entry && unlikely(mas_is_start(&mas))) | |
6260 | goto retry; | |
6261 | unlock: | |
6262 | rcu_read_unlock(); | |
6263 | if (xa_is_zero(entry)) | |
6264 | return NULL; | |
6265 | ||
6266 | return entry; | |
6267 | } | |
6268 | EXPORT_SYMBOL(mtree_load); | |
6269 | ||
6270 | /** | |
6271 | * mtree_store_range() - Store an entry at a given range. | |
6272 | * @mt: The maple tree | |
6273 | * @index: The start of the range | |
6274 | * @last: The end of the range | |
6275 | * @entry: The entry to store | |
6276 | * @gfp: The GFP_FLAGS to use for allocations | |
6277 | * | |
6278 | * Return: 0 on success, -EINVAL on invalid request, -ENOMEM if memory could not | |
6279 | * be allocated. | |
6280 | */ | |
6281 | int mtree_store_range(struct maple_tree *mt, unsigned long index, | |
6282 | unsigned long last, void *entry, gfp_t gfp) | |
6283 | { | |
6284 | MA_STATE(mas, mt, index, last); | |
6285 | MA_WR_STATE(wr_mas, &mas, entry); | |
6286 | ||
6287 | trace_ma_write(__func__, &mas, 0, entry); | |
6288 | if (WARN_ON_ONCE(xa_is_advanced(entry))) | |
6289 | return -EINVAL; | |
6290 | ||
6291 | if (index > last) | |
6292 | return -EINVAL; | |
6293 | ||
6294 | mtree_lock(mt); | |
6295 | retry: | |
6296 | mas_wr_store_entry(&wr_mas); | |
6297 | if (mas_nomem(&mas, gfp)) | |
6298 | goto retry; | |
6299 | ||
6300 | mtree_unlock(mt); | |
6301 | if (mas_is_err(&mas)) | |
6302 | return xa_err(mas.node); | |
6303 | ||
6304 | return 0; | |
6305 | } | |
6306 | EXPORT_SYMBOL(mtree_store_range); | |
6307 | ||
6308 | /** | |
6309 | * mtree_store() - Store an entry at a given index. | |
6310 | * @mt: The maple tree | |
6311 | * @index: The index to store the value | |
6312 | * @entry: The entry to store | |
6313 | * @gfp: The GFP_FLAGS to use for allocations | |
6314 | * | |
6315 | * Return: 0 on success, -EINVAL on invalid request, -ENOMEM if memory could not | |
6316 | * be allocated. | |
6317 | */ | |
6318 | int mtree_store(struct maple_tree *mt, unsigned long index, void *entry, | |
6319 | gfp_t gfp) | |
6320 | { | |
6321 | return mtree_store_range(mt, index, index, entry, gfp); | |
6322 | } | |
6323 | EXPORT_SYMBOL(mtree_store); | |
6324 | ||
6325 | /** | |
4445e582 | 6326 | * mtree_insert_range() - Insert an entry at a given range if there is no value. |
54a611b6 LH |
6327 | * @mt: The maple tree |
6328 | * @first: The start of the range | |
6329 | * @last: The end of the range | |
6330 | * @entry: The entry to store | |
6331 | * @gfp: The GFP_FLAGS to use for allocations. | |
6332 | * | |
6333 | * Return: 0 on success, -EEXISTS if the range is occupied, -EINVAL on invalid | |
6334 | * request, -ENOMEM if memory could not be allocated. | |
6335 | */ | |
6336 | int mtree_insert_range(struct maple_tree *mt, unsigned long first, | |
6337 | unsigned long last, void *entry, gfp_t gfp) | |
6338 | { | |
6339 | MA_STATE(ms, mt, first, last); | |
6340 | ||
6341 | if (WARN_ON_ONCE(xa_is_advanced(entry))) | |
6342 | return -EINVAL; | |
6343 | ||
6344 | if (first > last) | |
6345 | return -EINVAL; | |
6346 | ||
6347 | mtree_lock(mt); | |
6348 | retry: | |
6349 | mas_insert(&ms, entry); | |
6350 | if (mas_nomem(&ms, gfp)) | |
6351 | goto retry; | |
6352 | ||
6353 | mtree_unlock(mt); | |
6354 | if (mas_is_err(&ms)) | |
6355 | return xa_err(ms.node); | |
6356 | ||
6357 | return 0; | |
6358 | } | |
6359 | EXPORT_SYMBOL(mtree_insert_range); | |
6360 | ||
6361 | /** | |
4445e582 | 6362 | * mtree_insert() - Insert an entry at a given index if there is no value. |
54a611b6 LH |
6363 | * @mt: The maple tree |
6364 | * @index : The index to store the value | |
6365 | * @entry: The entry to store | |
4ae6944d | 6366 | * @gfp: The GFP_FLAGS to use for allocations. |
54a611b6 LH |
6367 | * |
6368 | * Return: 0 on success, -EEXISTS if the range is occupied, -EINVAL on invalid | |
6369 | * request, -ENOMEM if memory could not be allocated. | |
6370 | */ | |
6371 | int mtree_insert(struct maple_tree *mt, unsigned long index, void *entry, | |
6372 | gfp_t gfp) | |
6373 | { | |
6374 | return mtree_insert_range(mt, index, index, entry, gfp); | |
6375 | } | |
6376 | EXPORT_SYMBOL(mtree_insert); | |
6377 | ||
6378 | int mtree_alloc_range(struct maple_tree *mt, unsigned long *startp, | |
6379 | void *entry, unsigned long size, unsigned long min, | |
6380 | unsigned long max, gfp_t gfp) | |
6381 | { | |
6382 | int ret = 0; | |
6383 | ||
52371677 | 6384 | MA_STATE(mas, mt, 0, 0); |
54a611b6 LH |
6385 | if (!mt_is_alloc(mt)) |
6386 | return -EINVAL; | |
6387 | ||
6388 | if (WARN_ON_ONCE(mt_is_reserved(entry))) | |
6389 | return -EINVAL; | |
6390 | ||
54a611b6 LH |
6391 | mtree_lock(mt); |
6392 | retry: | |
52371677 PZ |
6393 | ret = mas_empty_area(&mas, min, max, size); |
6394 | if (ret) | |
6395 | goto unlock; | |
6396 | ||
6397 | mas_insert(&mas, entry); | |
6398 | /* | |
6399 | * mas_nomem() may release the lock, causing the allocated area | |
6400 | * to be unavailable, so try to allocate a free area again. | |
6401 | */ | |
54a611b6 LH |
6402 | if (mas_nomem(&mas, gfp)) |
6403 | goto retry; | |
6404 | ||
52371677 PZ |
6405 | if (mas_is_err(&mas)) |
6406 | ret = xa_err(mas.node); | |
6407 | else | |
6408 | *startp = mas.index; | |
6409 | ||
6410 | unlock: | |
54a611b6 LH |
6411 | mtree_unlock(mt); |
6412 | return ret; | |
6413 | } | |
6414 | EXPORT_SYMBOL(mtree_alloc_range); | |
6415 | ||
6416 | int mtree_alloc_rrange(struct maple_tree *mt, unsigned long *startp, | |
6417 | void *entry, unsigned long size, unsigned long min, | |
6418 | unsigned long max, gfp_t gfp) | |
6419 | { | |
6420 | int ret = 0; | |
6421 | ||
52371677 | 6422 | MA_STATE(mas, mt, 0, 0); |
54a611b6 LH |
6423 | if (!mt_is_alloc(mt)) |
6424 | return -EINVAL; | |
6425 | ||
6426 | if (WARN_ON_ONCE(mt_is_reserved(entry))) | |
6427 | return -EINVAL; | |
6428 | ||
54a611b6 LH |
6429 | mtree_lock(mt); |
6430 | retry: | |
52371677 PZ |
6431 | ret = mas_empty_area_rev(&mas, min, max, size); |
6432 | if (ret) | |
6433 | goto unlock; | |
6434 | ||
6435 | mas_insert(&mas, entry); | |
6436 | /* | |
6437 | * mas_nomem() may release the lock, causing the allocated area | |
6438 | * to be unavailable, so try to allocate a free area again. | |
6439 | */ | |
54a611b6 LH |
6440 | if (mas_nomem(&mas, gfp)) |
6441 | goto retry; | |
6442 | ||
52371677 PZ |
6443 | if (mas_is_err(&mas)) |
6444 | ret = xa_err(mas.node); | |
6445 | else | |
6446 | *startp = mas.index; | |
6447 | ||
6448 | unlock: | |
54a611b6 LH |
6449 | mtree_unlock(mt); |
6450 | return ret; | |
6451 | } | |
6452 | EXPORT_SYMBOL(mtree_alloc_rrange); | |
6453 | ||
6454 | /** | |
6455 | * mtree_erase() - Find an index and erase the entire range. | |
6456 | * @mt: The maple tree | |
6457 | * @index: The index to erase | |
6458 | * | |
6459 | * Erasing is the same as a walk to an entry then a store of a NULL to that | |
6460 | * ENTIRE range. In fact, it is implemented as such using the advanced API. | |
6461 | * | |
6462 | * Return: The entry stored at the @index or %NULL | |
6463 | */ | |
6464 | void *mtree_erase(struct maple_tree *mt, unsigned long index) | |
6465 | { | |
6466 | void *entry = NULL; | |
6467 | ||
6468 | MA_STATE(mas, mt, index, index); | |
6469 | trace_ma_op(__func__, &mas); | |
6470 | ||
6471 | mtree_lock(mt); | |
6472 | entry = mas_erase(&mas); | |
6473 | mtree_unlock(mt); | |
6474 | ||
6475 | return entry; | |
6476 | } | |
6477 | EXPORT_SYMBOL(mtree_erase); | |
6478 | ||
6479 | /** | |
6480 | * __mt_destroy() - Walk and free all nodes of a locked maple tree. | |
6481 | * @mt: The maple tree | |
6482 | * | |
6483 | * Note: Does not handle locking. | |
6484 | */ | |
6485 | void __mt_destroy(struct maple_tree *mt) | |
6486 | { | |
6487 | void *root = mt_root_locked(mt); | |
6488 | ||
6489 | rcu_assign_pointer(mt->ma_root, NULL); | |
6490 | if (xa_is_node(root)) | |
6491 | mte_destroy_walk(root, mt); | |
6492 | ||
6493 | mt->ma_flags = 0; | |
6494 | } | |
6495 | EXPORT_SYMBOL_GPL(__mt_destroy); | |
6496 | ||
6497 | /** | |
6498 | * mtree_destroy() - Destroy a maple tree | |
6499 | * @mt: The maple tree | |
6500 | * | |
6501 | * Frees all resources used by the tree. Handles locking. | |
6502 | */ | |
6503 | void mtree_destroy(struct maple_tree *mt) | |
6504 | { | |
6505 | mtree_lock(mt); | |
6506 | __mt_destroy(mt); | |
6507 | mtree_unlock(mt); | |
6508 | } | |
6509 | EXPORT_SYMBOL(mtree_destroy); | |
6510 | ||
6511 | /** | |
6512 | * mt_find() - Search from the start up until an entry is found. | |
6513 | * @mt: The maple tree | |
6514 | * @index: Pointer which contains the start location of the search | |
fad9c80e TG |
6515 | * @max: The maximum value of the search range |
6516 | * | |
6517 | * Takes RCU read lock internally to protect the search, which does not | |
6518 | * protect the returned pointer after dropping RCU read lock. | |
6519 | * See also: Documentation/core-api/maple_tree.rst | |
54a611b6 | 6520 | * |
fad9c80e TG |
6521 | * In case that an entry is found @index is updated to point to the next |
6522 | * possible entry independent whether the found entry is occupying a | |
6523 | * single index or a range if indices. | |
54a611b6 LH |
6524 | * |
6525 | * Return: The entry at or after the @index or %NULL | |
6526 | */ | |
6527 | void *mt_find(struct maple_tree *mt, unsigned long *index, unsigned long max) | |
6528 | { | |
6529 | MA_STATE(mas, mt, *index, *index); | |
6530 | void *entry; | |
6531 | #ifdef CONFIG_DEBUG_MAPLE_TREE | |
6532 | unsigned long copy = *index; | |
6533 | #endif | |
6534 | ||
6535 | trace_ma_read(__func__, &mas); | |
6536 | ||
6537 | if ((*index) > max) | |
6538 | return NULL; | |
6539 | ||
6540 | rcu_read_lock(); | |
6541 | retry: | |
6542 | entry = mas_state_walk(&mas); | |
6543 | if (mas_is_start(&mas)) | |
6544 | goto retry; | |
6545 | ||
6546 | if (unlikely(xa_is_zero(entry))) | |
6547 | entry = NULL; | |
6548 | ||
6549 | if (entry) | |
6550 | goto unlock; | |
6551 | ||
ca80f610 | 6552 | while (mas_searchable(&mas) && (mas.last < max)) { |
54a611b6 LH |
6553 | entry = mas_next_entry(&mas, max); |
6554 | if (likely(entry && !xa_is_zero(entry))) | |
6555 | break; | |
6556 | } | |
6557 | ||
6558 | if (unlikely(xa_is_zero(entry))) | |
6559 | entry = NULL; | |
6560 | unlock: | |
6561 | rcu_read_unlock(); | |
6562 | if (likely(entry)) { | |
6563 | *index = mas.last + 1; | |
6564 | #ifdef CONFIG_DEBUG_MAPLE_TREE | |
e6d6792a | 6565 | if (MT_WARN_ON(mt, (*index) && ((*index) <= copy))) |
54a611b6 LH |
6566 | pr_err("index not increased! %lx <= %lx\n", |
6567 | *index, copy); | |
54a611b6 LH |
6568 | #endif |
6569 | } | |
6570 | ||
6571 | return entry; | |
6572 | } | |
6573 | EXPORT_SYMBOL(mt_find); | |
6574 | ||
6575 | /** | |
6576 | * mt_find_after() - Search from the start up until an entry is found. | |
6577 | * @mt: The maple tree | |
6578 | * @index: Pointer which contains the start location of the search | |
6579 | * @max: The maximum value to check | |
6580 | * | |
fad9c80e TG |
6581 | * Same as mt_find() except that it checks @index for 0 before |
6582 | * searching. If @index == 0, the search is aborted. This covers a wrap | |
6583 | * around of @index to 0 in an iterator loop. | |
54a611b6 LH |
6584 | * |
6585 | * Return: The entry at or after the @index or %NULL | |
6586 | */ | |
6587 | void *mt_find_after(struct maple_tree *mt, unsigned long *index, | |
6588 | unsigned long max) | |
6589 | { | |
6590 | if (!(*index)) | |
6591 | return NULL; | |
6592 | ||
6593 | return mt_find(mt, index, max); | |
6594 | } | |
6595 | EXPORT_SYMBOL(mt_find_after); | |
6596 | ||
6597 | #ifdef CONFIG_DEBUG_MAPLE_TREE | |
6598 | atomic_t maple_tree_tests_run; | |
6599 | EXPORT_SYMBOL_GPL(maple_tree_tests_run); | |
6600 | atomic_t maple_tree_tests_passed; | |
6601 | EXPORT_SYMBOL_GPL(maple_tree_tests_passed); | |
6602 | ||
6603 | #ifndef __KERNEL__ | |
6604 | extern void kmem_cache_set_non_kernel(struct kmem_cache *, unsigned int); | |
6605 | void mt_set_non_kernel(unsigned int val) | |
6606 | { | |
6607 | kmem_cache_set_non_kernel(maple_node_cache, val); | |
6608 | } | |
6609 | ||
6610 | extern unsigned long kmem_cache_get_alloc(struct kmem_cache *); | |
6611 | unsigned long mt_get_alloc_size(void) | |
6612 | { | |
6613 | return kmem_cache_get_alloc(maple_node_cache); | |
6614 | } | |
6615 | ||
6616 | extern void kmem_cache_zero_nr_tallocated(struct kmem_cache *); | |
6617 | void mt_zero_nr_tallocated(void) | |
6618 | { | |
6619 | kmem_cache_zero_nr_tallocated(maple_node_cache); | |
6620 | } | |
6621 | ||
6622 | extern unsigned int kmem_cache_nr_tallocated(struct kmem_cache *); | |
6623 | unsigned int mt_nr_tallocated(void) | |
6624 | { | |
6625 | return kmem_cache_nr_tallocated(maple_node_cache); | |
6626 | } | |
6627 | ||
6628 | extern unsigned int kmem_cache_nr_allocated(struct kmem_cache *); | |
6629 | unsigned int mt_nr_allocated(void) | |
6630 | { | |
6631 | return kmem_cache_nr_allocated(maple_node_cache); | |
6632 | } | |
6633 | ||
6634 | /* | |
6635 | * mas_dead_node() - Check if the maple state is pointing to a dead node. | |
6636 | * @mas: The maple state | |
6637 | * @index: The index to restore in @mas. | |
6638 | * | |
6639 | * Used in test code. | |
6640 | * Return: 1 if @mas has been reset to MAS_START, 0 otherwise. | |
6641 | */ | |
6642 | static inline int mas_dead_node(struct ma_state *mas, unsigned long index) | |
6643 | { | |
6644 | if (unlikely(!mas_searchable(mas) || mas_is_start(mas))) | |
6645 | return 0; | |
6646 | ||
6647 | if (likely(!mte_dead_node(mas->node))) | |
6648 | return 0; | |
6649 | ||
6650 | mas_rewalk(mas, index); | |
6651 | return 1; | |
6652 | } | |
54a611b6 | 6653 | |
120b1162 LH |
6654 | void mt_cache_shrink(void) |
6655 | { | |
6656 | } | |
6657 | #else | |
6658 | /* | |
6659 | * mt_cache_shrink() - For testing, don't use this. | |
6660 | * | |
6661 | * Certain testcases can trigger an OOM when combined with other memory | |
6662 | * debugging configuration options. This function is used to reduce the | |
6663 | * possibility of an out of memory even due to kmem_cache objects remaining | |
6664 | * around for longer than usual. | |
6665 | */ | |
6666 | void mt_cache_shrink(void) | |
6667 | { | |
6668 | kmem_cache_shrink(maple_node_cache); | |
6669 | ||
6670 | } | |
6671 | EXPORT_SYMBOL_GPL(mt_cache_shrink); | |
6672 | ||
6673 | #endif /* not defined __KERNEL__ */ | |
54a611b6 LH |
6674 | /* |
6675 | * mas_get_slot() - Get the entry in the maple state node stored at @offset. | |
6676 | * @mas: The maple state | |
6677 | * @offset: The offset into the slot array to fetch. | |
6678 | * | |
6679 | * Return: The entry stored at @offset. | |
6680 | */ | |
6681 | static inline struct maple_enode *mas_get_slot(struct ma_state *mas, | |
6682 | unsigned char offset) | |
6683 | { | |
6684 | return mas_slot(mas, ma_slots(mas_mn(mas), mte_node_type(mas->node)), | |
6685 | offset); | |
6686 | } | |
6687 | ||
54a611b6 LH |
6688 | /* Depth first search, post-order */ |
6689 | static void mas_dfs_postorder(struct ma_state *mas, unsigned long max) | |
6690 | { | |
6691 | ||
6692 | struct maple_enode *p = MAS_NONE, *mn = mas->node; | |
6693 | unsigned long p_min, p_max; | |
6694 | ||
6695 | mas_next_node(mas, mas_mn(mas), max); | |
6696 | if (!mas_is_none(mas)) | |
6697 | return; | |
6698 | ||
6699 | if (mte_is_root(mn)) | |
6700 | return; | |
6701 | ||
6702 | mas->node = mn; | |
6703 | mas_ascend(mas); | |
c3eb787e | 6704 | do { |
54a611b6 LH |
6705 | p = mas->node; |
6706 | p_min = mas->min; | |
6707 | p_max = mas->max; | |
6708 | mas_prev_node(mas, 0); | |
c3eb787e | 6709 | } while (!mas_is_none(mas)); |
54a611b6 LH |
6710 | |
6711 | mas->node = p; | |
6712 | mas->max = p_max; | |
6713 | mas->min = p_min; | |
6714 | } | |
6715 | ||
6716 | /* Tree validations */ | |
6717 | static void mt_dump_node(const struct maple_tree *mt, void *entry, | |
89f499f3 LH |
6718 | unsigned long min, unsigned long max, unsigned int depth, |
6719 | enum mt_dump_format format); | |
54a611b6 | 6720 | static void mt_dump_range(unsigned long min, unsigned long max, |
89f499f3 | 6721 | unsigned int depth, enum mt_dump_format format) |
54a611b6 LH |
6722 | { |
6723 | static const char spaces[] = " "; | |
6724 | ||
89f499f3 LH |
6725 | switch(format) { |
6726 | case mt_dump_hex: | |
6727 | if (min == max) | |
6728 | pr_info("%.*s%lx: ", depth * 2, spaces, min); | |
6729 | else | |
6730 | pr_info("%.*s%lx-%lx: ", depth * 2, spaces, min, max); | |
6731 | break; | |
6732 | default: | |
6733 | case mt_dump_dec: | |
6734 | if (min == max) | |
6735 | pr_info("%.*s%lu: ", depth * 2, spaces, min); | |
6736 | else | |
6737 | pr_info("%.*s%lu-%lu: ", depth * 2, spaces, min, max); | |
6738 | } | |
54a611b6 LH |
6739 | } |
6740 | ||
6741 | static void mt_dump_entry(void *entry, unsigned long min, unsigned long max, | |
89f499f3 | 6742 | unsigned int depth, enum mt_dump_format format) |
54a611b6 | 6743 | { |
89f499f3 | 6744 | mt_dump_range(min, max, depth, format); |
54a611b6 LH |
6745 | |
6746 | if (xa_is_value(entry)) | |
6747 | pr_cont("value %ld (0x%lx) [%p]\n", xa_to_value(entry), | |
6748 | xa_to_value(entry), entry); | |
6749 | else if (xa_is_zero(entry)) | |
6750 | pr_cont("zero (%ld)\n", xa_to_internal(entry)); | |
6751 | else if (mt_is_reserved(entry)) | |
6752 | pr_cont("UNKNOWN ENTRY (%p)\n", entry); | |
6753 | else | |
6754 | pr_cont("%p\n", entry); | |
6755 | } | |
6756 | ||
6757 | static void mt_dump_range64(const struct maple_tree *mt, void *entry, | |
89f499f3 LH |
6758 | unsigned long min, unsigned long max, unsigned int depth, |
6759 | enum mt_dump_format format) | |
54a611b6 LH |
6760 | { |
6761 | struct maple_range_64 *node = &mte_to_node(entry)->mr64; | |
6762 | bool leaf = mte_is_leaf(entry); | |
6763 | unsigned long first = min; | |
6764 | int i; | |
6765 | ||
6766 | pr_cont(" contents: "); | |
89f499f3 LH |
6767 | for (i = 0; i < MAPLE_RANGE64_SLOTS - 1; i++) { |
6768 | switch(format) { | |
6769 | case mt_dump_hex: | |
6770 | pr_cont("%p %lX ", node->slot[i], node->pivot[i]); | |
6771 | break; | |
6772 | default: | |
6773 | case mt_dump_dec: | |
6774 | pr_cont("%p %lu ", node->slot[i], node->pivot[i]); | |
6775 | } | |
6776 | } | |
54a611b6 LH |
6777 | pr_cont("%p\n", node->slot[i]); |
6778 | for (i = 0; i < MAPLE_RANGE64_SLOTS; i++) { | |
6779 | unsigned long last = max; | |
6780 | ||
6781 | if (i < (MAPLE_RANGE64_SLOTS - 1)) | |
6782 | last = node->pivot[i]; | |
bd592703 | 6783 | else if (!node->slot[i] && max != mt_node_max(entry)) |
54a611b6 LH |
6784 | break; |
6785 | if (last == 0 && i > 0) | |
6786 | break; | |
6787 | if (leaf) | |
6788 | mt_dump_entry(mt_slot(mt, node->slot, i), | |
89f499f3 | 6789 | first, last, depth + 1, format); |
54a611b6 LH |
6790 | else if (node->slot[i]) |
6791 | mt_dump_node(mt, mt_slot(mt, node->slot, i), | |
89f499f3 | 6792 | first, last, depth + 1, format); |
54a611b6 LH |
6793 | |
6794 | if (last == max) | |
6795 | break; | |
6796 | if (last > max) { | |
89f499f3 LH |
6797 | switch(format) { |
6798 | case mt_dump_hex: | |
6799 | pr_err("node %p last (%lx) > max (%lx) at pivot %d!\n", | |
54a611b6 | 6800 | node, last, max, i); |
89f499f3 LH |
6801 | break; |
6802 | default: | |
6803 | case mt_dump_dec: | |
6804 | pr_err("node %p last (%lu) > max (%lu) at pivot %d!\n", | |
6805 | node, last, max, i); | |
6806 | } | |
54a611b6 LH |
6807 | } |
6808 | first = last + 1; | |
6809 | } | |
6810 | } | |
6811 | ||
6812 | static void mt_dump_arange64(const struct maple_tree *mt, void *entry, | |
89f499f3 LH |
6813 | unsigned long min, unsigned long max, unsigned int depth, |
6814 | enum mt_dump_format format) | |
54a611b6 LH |
6815 | { |
6816 | struct maple_arange_64 *node = &mte_to_node(entry)->ma64; | |
6817 | bool leaf = mte_is_leaf(entry); | |
6818 | unsigned long first = min; | |
6819 | int i; | |
6820 | ||
6821 | pr_cont(" contents: "); | |
83d97f62 LH |
6822 | for (i = 0; i < MAPLE_ARANGE64_SLOTS; i++) { |
6823 | switch (format) { | |
6824 | case mt_dump_hex: | |
6825 | pr_cont("%lx ", node->gap[i]); | |
6826 | break; | |
6827 | default: | |
6828 | case mt_dump_dec: | |
6829 | pr_cont("%lu ", node->gap[i]); | |
6830 | } | |
6831 | } | |
54a611b6 | 6832 | pr_cont("| %02X %02X| ", node->meta.end, node->meta.gap); |
83d97f62 LH |
6833 | for (i = 0; i < MAPLE_ARANGE64_SLOTS - 1; i++) { |
6834 | switch (format) { | |
6835 | case mt_dump_hex: | |
6836 | pr_cont("%p %lX ", node->slot[i], node->pivot[i]); | |
6837 | break; | |
6838 | default: | |
6839 | case mt_dump_dec: | |
6840 | pr_cont("%p %lu ", node->slot[i], node->pivot[i]); | |
6841 | } | |
6842 | } | |
54a611b6 LH |
6843 | pr_cont("%p\n", node->slot[i]); |
6844 | for (i = 0; i < MAPLE_ARANGE64_SLOTS; i++) { | |
6845 | unsigned long last = max; | |
6846 | ||
6847 | if (i < (MAPLE_ARANGE64_SLOTS - 1)) | |
6848 | last = node->pivot[i]; | |
6849 | else if (!node->slot[i]) | |
6850 | break; | |
6851 | if (last == 0 && i > 0) | |
6852 | break; | |
6853 | if (leaf) | |
6854 | mt_dump_entry(mt_slot(mt, node->slot, i), | |
89f499f3 | 6855 | first, last, depth + 1, format); |
54a611b6 LH |
6856 | else if (node->slot[i]) |
6857 | mt_dump_node(mt, mt_slot(mt, node->slot, i), | |
89f499f3 | 6858 | first, last, depth + 1, format); |
54a611b6 LH |
6859 | |
6860 | if (last == max) | |
6861 | break; | |
6862 | if (last > max) { | |
6863 | pr_err("node %p last (%lu) > max (%lu) at pivot %d!\n", | |
6864 | node, last, max, i); | |
6865 | break; | |
6866 | } | |
6867 | first = last + 1; | |
6868 | } | |
6869 | } | |
6870 | ||
6871 | static void mt_dump_node(const struct maple_tree *mt, void *entry, | |
89f499f3 LH |
6872 | unsigned long min, unsigned long max, unsigned int depth, |
6873 | enum mt_dump_format format) | |
54a611b6 LH |
6874 | { |
6875 | struct maple_node *node = mte_to_node(entry); | |
6876 | unsigned int type = mte_node_type(entry); | |
6877 | unsigned int i; | |
6878 | ||
89f499f3 | 6879 | mt_dump_range(min, max, depth, format); |
54a611b6 LH |
6880 | |
6881 | pr_cont("node %p depth %d type %d parent %p", node, depth, type, | |
6882 | node ? node->parent : NULL); | |
6883 | switch (type) { | |
6884 | case maple_dense: | |
6885 | pr_cont("\n"); | |
6886 | for (i = 0; i < MAPLE_NODE_SLOTS; i++) { | |
6887 | if (min + i > max) | |
6888 | pr_cont("OUT OF RANGE: "); | |
6889 | mt_dump_entry(mt_slot(mt, node->slot, i), | |
89f499f3 | 6890 | min + i, min + i, depth, format); |
54a611b6 LH |
6891 | } |
6892 | break; | |
6893 | case maple_leaf_64: | |
6894 | case maple_range_64: | |
89f499f3 | 6895 | mt_dump_range64(mt, entry, min, max, depth, format); |
54a611b6 LH |
6896 | break; |
6897 | case maple_arange_64: | |
89f499f3 | 6898 | mt_dump_arange64(mt, entry, min, max, depth, format); |
54a611b6 LH |
6899 | break; |
6900 | ||
6901 | default: | |
6902 | pr_cont(" UNKNOWN TYPE\n"); | |
6903 | } | |
6904 | } | |
6905 | ||
89f499f3 | 6906 | void mt_dump(const struct maple_tree *mt, enum mt_dump_format format) |
54a611b6 LH |
6907 | { |
6908 | void *entry = rcu_dereference_check(mt->ma_root, mt_locked(mt)); | |
6909 | ||
6910 | pr_info("maple_tree(%p) flags %X, height %u root %p\n", | |
6911 | mt, mt->ma_flags, mt_height(mt), entry); | |
6912 | if (!xa_is_node(entry)) | |
89f499f3 | 6913 | mt_dump_entry(entry, 0, 0, 0, format); |
54a611b6 | 6914 | else if (entry) |
89f499f3 | 6915 | mt_dump_node(mt, entry, 0, mt_node_max(entry), 0, format); |
54a611b6 | 6916 | } |
120b1162 | 6917 | EXPORT_SYMBOL_GPL(mt_dump); |
54a611b6 LH |
6918 | |
6919 | /* | |
6920 | * Calculate the maximum gap in a node and check if that's what is reported in | |
6921 | * the parent (unless root). | |
6922 | */ | |
6923 | static void mas_validate_gaps(struct ma_state *mas) | |
6924 | { | |
6925 | struct maple_enode *mte = mas->node; | |
f8e5eac8 PZ |
6926 | struct maple_node *p_mn, *node = mte_to_node(mte); |
6927 | enum maple_type mt = mte_node_type(mas->node); | |
54a611b6 LH |
6928 | unsigned long gap = 0, max_gap = 0; |
6929 | unsigned long p_end, p_start = mas->min; | |
f8e5eac8 | 6930 | unsigned char p_slot, offset; |
54a611b6 | 6931 | unsigned long *gaps = NULL; |
f8e5eac8 PZ |
6932 | unsigned long *pivots = ma_pivots(node, mt); |
6933 | unsigned int i; | |
54a611b6 | 6934 | |
f8e5eac8 | 6935 | if (ma_is_dense(mt)) { |
54a611b6 LH |
6936 | for (i = 0; i < mt_slot_count(mte); i++) { |
6937 | if (mas_get_slot(mas, i)) { | |
6938 | if (gap > max_gap) | |
6939 | max_gap = gap; | |
6940 | gap = 0; | |
6941 | continue; | |
6942 | } | |
6943 | gap++; | |
6944 | } | |
6945 | goto counted; | |
6946 | } | |
6947 | ||
f8e5eac8 | 6948 | gaps = ma_gaps(node, mt); |
54a611b6 | 6949 | for (i = 0; i < mt_slot_count(mte); i++) { |
29b2681f | 6950 | p_end = mas_safe_pivot(mas, pivots, i, mt); |
54a611b6 LH |
6951 | |
6952 | if (!gaps) { | |
f8e5eac8 PZ |
6953 | if (!mas_get_slot(mas, i)) |
6954 | gap = p_end - p_start + 1; | |
54a611b6 LH |
6955 | } else { |
6956 | void *entry = mas_get_slot(mas, i); | |
6957 | ||
6958 | gap = gaps[i]; | |
f8e5eac8 PZ |
6959 | MT_BUG_ON(mas->tree, !entry); |
6960 | ||
6961 | if (gap > p_end - p_start + 1) { | |
6962 | pr_err("%p[%u] %lu >= %lu - %lu + 1 (%lu)\n", | |
6963 | mas_mn(mas), i, gap, p_end, p_start, | |
6964 | p_end - p_start + 1); | |
6965 | MT_BUG_ON(mas->tree, gap > p_end - p_start + 1); | |
54a611b6 LH |
6966 | } |
6967 | } | |
6968 | ||
6969 | if (gap > max_gap) | |
6970 | max_gap = gap; | |
f8e5eac8 | 6971 | |
54a611b6 LH |
6972 | p_start = p_end + 1; |
6973 | if (p_end >= mas->max) | |
6974 | break; | |
6975 | } | |
6976 | ||
6977 | counted: | |
f8e5eac8 PZ |
6978 | if (mt == maple_arange_64) { |
6979 | offset = ma_meta_gap(node, mt); | |
6980 | if (offset > i) { | |
6981 | pr_err("gap offset %p[%u] is invalid\n", node, offset); | |
6982 | MT_BUG_ON(mas->tree, 1); | |
6983 | } | |
6984 | ||
6985 | if (gaps[offset] != max_gap) { | |
6986 | pr_err("gap %p[%u] is not the largest gap %lu\n", | |
6987 | node, offset, max_gap); | |
6988 | MT_BUG_ON(mas->tree, 1); | |
6989 | } | |
6990 | ||
6991 | MT_BUG_ON(mas->tree, !gaps); | |
6992 | for (i++ ; i < mt_slot_count(mte); i++) { | |
6993 | if (gaps[i] != 0) { | |
6994 | pr_err("gap %p[%u] beyond node limit != 0\n", | |
6995 | node, i); | |
6996 | MT_BUG_ON(mas->tree, 1); | |
6997 | } | |
6998 | } | |
6999 | } | |
7000 | ||
54a611b6 LH |
7001 | if (mte_is_root(mte)) |
7002 | return; | |
7003 | ||
7004 | p_slot = mte_parent_slot(mas->node); | |
7005 | p_mn = mte_parent(mte); | |
7006 | MT_BUG_ON(mas->tree, max_gap > mas->max); | |
afc754c6 | 7007 | if (ma_gaps(p_mn, mas_parent_type(mas, mte))[p_slot] != max_gap) { |
54a611b6 | 7008 | pr_err("gap %p[%u] != %lu\n", p_mn, p_slot, max_gap); |
89f499f3 | 7009 | mt_dump(mas->tree, mt_dump_hex); |
f8e5eac8 | 7010 | MT_BUG_ON(mas->tree, 1); |
54a611b6 | 7011 | } |
54a611b6 LH |
7012 | } |
7013 | ||
7014 | static void mas_validate_parent_slot(struct ma_state *mas) | |
7015 | { | |
7016 | struct maple_node *parent; | |
7017 | struct maple_enode *node; | |
afc754c6 LH |
7018 | enum maple_type p_type; |
7019 | unsigned char p_slot; | |
54a611b6 LH |
7020 | void __rcu **slots; |
7021 | int i; | |
7022 | ||
7023 | if (mte_is_root(mas->node)) | |
7024 | return; | |
7025 | ||
afc754c6 LH |
7026 | p_slot = mte_parent_slot(mas->node); |
7027 | p_type = mas_parent_type(mas, mas->node); | |
54a611b6 LH |
7028 | parent = mte_parent(mas->node); |
7029 | slots = ma_slots(parent, p_type); | |
7030 | MT_BUG_ON(mas->tree, mas_mn(mas) == parent); | |
7031 | ||
7032 | /* Check prev/next parent slot for duplicate node entry */ | |
7033 | ||
7034 | for (i = 0; i < mt_slots[p_type]; i++) { | |
7035 | node = mas_slot(mas, slots, i); | |
7036 | if (i == p_slot) { | |
7037 | if (node != mas->node) | |
7038 | pr_err("parent %p[%u] does not have %p\n", | |
7039 | parent, i, mas_mn(mas)); | |
7040 | MT_BUG_ON(mas->tree, node != mas->node); | |
7041 | } else if (node == mas->node) { | |
7042 | pr_err("Invalid child %p at parent %p[%u] p_slot %u\n", | |
7043 | mas_mn(mas), parent, i, p_slot); | |
7044 | MT_BUG_ON(mas->tree, node == mas->node); | |
7045 | } | |
7046 | } | |
7047 | } | |
7048 | ||
7049 | static void mas_validate_child_slot(struct ma_state *mas) | |
7050 | { | |
7051 | enum maple_type type = mte_node_type(mas->node); | |
7052 | void __rcu **slots = ma_slots(mte_to_node(mas->node), type); | |
7053 | unsigned long *pivots = ma_pivots(mte_to_node(mas->node), type); | |
7054 | struct maple_enode *child; | |
7055 | unsigned char i; | |
7056 | ||
7057 | if (mte_is_leaf(mas->node)) | |
7058 | return; | |
7059 | ||
7060 | for (i = 0; i < mt_slots[type]; i++) { | |
7061 | child = mas_slot(mas, slots, i); | |
54a611b6 | 7062 | |
e93fda5a PZ |
7063 | if (!child) { |
7064 | pr_err("Non-leaf node lacks child at %p[%u]\n", | |
7065 | mas_mn(mas), i); | |
7066 | MT_BUG_ON(mas->tree, 1); | |
7067 | } | |
54a611b6 LH |
7068 | |
7069 | if (mte_parent_slot(child) != i) { | |
7070 | pr_err("Slot error at %p[%u]: child %p has pslot %u\n", | |
7071 | mas_mn(mas), i, mte_to_node(child), | |
7072 | mte_parent_slot(child)); | |
7073 | MT_BUG_ON(mas->tree, 1); | |
7074 | } | |
7075 | ||
7076 | if (mte_parent(child) != mte_to_node(mas->node)) { | |
7077 | pr_err("child %p has parent %p not %p\n", | |
7078 | mte_to_node(child), mte_parent(child), | |
7079 | mte_to_node(mas->node)); | |
7080 | MT_BUG_ON(mas->tree, 1); | |
7081 | } | |
e93fda5a PZ |
7082 | |
7083 | if (i < mt_pivots[type] && pivots[i] == mas->max) | |
7084 | break; | |
54a611b6 LH |
7085 | } |
7086 | } | |
7087 | ||
7088 | /* | |
33af39d0 PZ |
7089 | * Validate all pivots are within mas->min and mas->max, check metadata ends |
7090 | * where the maximum ends and ensure there is no slots or pivots set outside of | |
7091 | * the end of the data. | |
54a611b6 LH |
7092 | */ |
7093 | static void mas_validate_limits(struct ma_state *mas) | |
7094 | { | |
7095 | int i; | |
7096 | unsigned long prev_piv = 0; | |
7097 | enum maple_type type = mte_node_type(mas->node); | |
7098 | void __rcu **slots = ma_slots(mte_to_node(mas->node), type); | |
7099 | unsigned long *pivots = ma_pivots(mas_mn(mas), type); | |
7100 | ||
54a611b6 LH |
7101 | for (i = 0; i < mt_slots[type]; i++) { |
7102 | unsigned long piv; | |
7103 | ||
7104 | piv = mas_safe_pivot(mas, pivots, i, type); | |
7105 | ||
33af39d0 PZ |
7106 | if (!piv && (i != 0)) { |
7107 | pr_err("Missing node limit pivot at %p[%u]", | |
7108 | mas_mn(mas), i); | |
7109 | MAS_WARN_ON(mas, 1); | |
54a611b6 LH |
7110 | } |
7111 | ||
7112 | if (prev_piv > piv) { | |
7113 | pr_err("%p[%u] piv %lu < prev_piv %lu\n", | |
7114 | mas_mn(mas), i, piv, prev_piv); | |
e6d6792a | 7115 | MAS_WARN_ON(mas, piv < prev_piv); |
54a611b6 LH |
7116 | } |
7117 | ||
7118 | if (piv < mas->min) { | |
7119 | pr_err("%p[%u] %lu < %lu\n", mas_mn(mas), i, | |
7120 | piv, mas->min); | |
e6d6792a | 7121 | MAS_WARN_ON(mas, piv < mas->min); |
54a611b6 LH |
7122 | } |
7123 | if (piv > mas->max) { | |
7124 | pr_err("%p[%u] %lu > %lu\n", mas_mn(mas), i, | |
7125 | piv, mas->max); | |
e6d6792a | 7126 | MAS_WARN_ON(mas, piv > mas->max); |
54a611b6 LH |
7127 | } |
7128 | prev_piv = piv; | |
7129 | if (piv == mas->max) | |
7130 | break; | |
7131 | } | |
33af39d0 PZ |
7132 | |
7133 | if (mas_data_end(mas) != i) { | |
7134 | pr_err("node%p: data_end %u != the last slot offset %u\n", | |
7135 | mas_mn(mas), mas_data_end(mas), i); | |
7136 | MT_BUG_ON(mas->tree, 1); | |
7137 | } | |
7138 | ||
54a611b6 LH |
7139 | for (i += 1; i < mt_slots[type]; i++) { |
7140 | void *entry = mas_slot(mas, slots, i); | |
7141 | ||
7142 | if (entry && (i != mt_slots[type] - 1)) { | |
7143 | pr_err("%p[%u] should not have entry %p\n", mas_mn(mas), | |
7144 | i, entry); | |
7145 | MT_BUG_ON(mas->tree, entry != NULL); | |
7146 | } | |
7147 | ||
7148 | if (i < mt_pivots[type]) { | |
7149 | unsigned long piv = pivots[i]; | |
7150 | ||
7151 | if (!piv) | |
7152 | continue; | |
7153 | ||
7154 | pr_err("%p[%u] should not have piv %lu\n", | |
7155 | mas_mn(mas), i, piv); | |
e6d6792a | 7156 | MAS_WARN_ON(mas, i < mt_pivots[type] - 1); |
54a611b6 LH |
7157 | } |
7158 | } | |
7159 | } | |
7160 | ||
7161 | static void mt_validate_nulls(struct maple_tree *mt) | |
7162 | { | |
7163 | void *entry, *last = (void *)1; | |
7164 | unsigned char offset = 0; | |
7165 | void __rcu **slots; | |
7166 | MA_STATE(mas, mt, 0, 0); | |
7167 | ||
7168 | mas_start(&mas); | |
7169 | if (mas_is_none(&mas) || (mas.node == MAS_ROOT)) | |
7170 | return; | |
7171 | ||
7172 | while (!mte_is_leaf(mas.node)) | |
7173 | mas_descend(&mas); | |
7174 | ||
7175 | slots = ma_slots(mte_to_node(mas.node), mte_node_type(mas.node)); | |
7176 | do { | |
7177 | entry = mas_slot(&mas, slots, offset); | |
7178 | if (!last && !entry) { | |
7179 | pr_err("Sequential nulls end at %p[%u]\n", | |
7180 | mas_mn(&mas), offset); | |
7181 | } | |
7182 | MT_BUG_ON(mt, !last && !entry); | |
7183 | last = entry; | |
7184 | if (offset == mas_data_end(&mas)) { | |
7185 | mas_next_node(&mas, mas_mn(&mas), ULONG_MAX); | |
7186 | if (mas_is_none(&mas)) | |
7187 | return; | |
7188 | offset = 0; | |
7189 | slots = ma_slots(mte_to_node(mas.node), | |
7190 | mte_node_type(mas.node)); | |
7191 | } else { | |
7192 | offset++; | |
7193 | } | |
7194 | ||
7195 | } while (!mas_is_none(&mas)); | |
7196 | } | |
7197 | ||
7198 | /* | |
7199 | * validate a maple tree by checking: | |
7200 | * 1. The limits (pivots are within mas->min to mas->max) | |
7201 | * 2. The gap is correctly set in the parents | |
7202 | */ | |
7203 | void mt_validate(struct maple_tree *mt) | |
7204 | { | |
7205 | unsigned char end; | |
7206 | ||
7207 | MA_STATE(mas, mt, 0, 0); | |
7208 | rcu_read_lock(); | |
7209 | mas_start(&mas); | |
7210 | if (!mas_searchable(&mas)) | |
7211 | goto done; | |
7212 | ||
a489539e PZ |
7213 | while (!mte_is_leaf(mas.node)) |
7214 | mas_descend(&mas); | |
7215 | ||
54a611b6 | 7216 | while (!mas_is_none(&mas)) { |
e6d6792a | 7217 | MAS_WARN_ON(&mas, mte_dead_node(mas.node)); |
a489539e PZ |
7218 | end = mas_data_end(&mas); |
7219 | if (MAS_WARN_ON(&mas, (end < mt_min_slot_count(mas.node)) && | |
7220 | (mas.max != ULONG_MAX))) { | |
7221 | pr_err("Invalid size %u of %p\n", end, mas_mn(&mas)); | |
54a611b6 | 7222 | } |
a489539e | 7223 | |
54a611b6 | 7224 | mas_validate_parent_slot(&mas); |
54a611b6 | 7225 | mas_validate_limits(&mas); |
a489539e | 7226 | mas_validate_child_slot(&mas); |
54a611b6 LH |
7227 | if (mt_is_alloc(mt)) |
7228 | mas_validate_gaps(&mas); | |
7229 | mas_dfs_postorder(&mas, ULONG_MAX); | |
7230 | } | |
7231 | mt_validate_nulls(mt); | |
7232 | done: | |
7233 | rcu_read_unlock(); | |
7234 | ||
7235 | } | |
120b1162 | 7236 | EXPORT_SYMBOL_GPL(mt_validate); |
54a611b6 | 7237 | |
f0a1f866 LH |
7238 | void mas_dump(const struct ma_state *mas) |
7239 | { | |
7240 | pr_err("MAS: tree=%p enode=%p ", mas->tree, mas->node); | |
7241 | if (mas_is_none(mas)) | |
7242 | pr_err("(MAS_NONE) "); | |
7243 | else if (mas_is_ptr(mas)) | |
7244 | pr_err("(MAS_ROOT) "); | |
7245 | else if (mas_is_start(mas)) | |
7246 | pr_err("(MAS_START) "); | |
7247 | else if (mas_is_paused(mas)) | |
7248 | pr_err("(MAS_PAUSED) "); | |
7249 | ||
7250 | pr_err("[%u] index=%lx last=%lx\n", mas->offset, mas->index, mas->last); | |
7251 | pr_err(" min=%lx max=%lx alloc=%p, depth=%u, flags=%x\n", | |
7252 | mas->min, mas->max, mas->alloc, mas->depth, mas->mas_flags); | |
7253 | if (mas->index > mas->last) | |
7254 | pr_err("Check index & last\n"); | |
7255 | } | |
7256 | EXPORT_SYMBOL_GPL(mas_dump); | |
7257 | ||
7258 | void mas_wr_dump(const struct ma_wr_state *wr_mas) | |
7259 | { | |
7260 | pr_err("WR_MAS: node=%p r_min=%lx r_max=%lx\n", | |
7261 | wr_mas->node, wr_mas->r_min, wr_mas->r_max); | |
7262 | pr_err(" type=%u off_end=%u, node_end=%u, end_piv=%lx\n", | |
7263 | wr_mas->type, wr_mas->offset_end, wr_mas->node_end, | |
7264 | wr_mas->end_piv); | |
7265 | } | |
7266 | EXPORT_SYMBOL_GPL(mas_wr_dump); | |
7267 | ||
54a611b6 | 7268 | #endif /* CONFIG_DEBUG_MAPLE_TREE */ |