Commit | Line | Data |
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de6cc651 | 1 | /* SPDX-License-Identifier: GPL-2.0-or-later */ |
1da177e4 LT |
2 | /* |
3 | * Copyright (C) 2001 Momchil Velikov | |
4 | * Portions Copyright (C) 2001 Christoph Hellwig | |
7cf9c2c7 | 5 | * Copyright (C) 2006 Nick Piggin |
78c1d784 | 6 | * Copyright (C) 2012 Konstantin Khlebnikov |
1da177e4 LT |
7 | */ |
8 | #ifndef _LINUX_RADIX_TREE_H | |
9 | #define _LINUX_RADIX_TREE_H | |
10 | ||
f67c07f0 | 11 | #include <linux/bitops.h> |
7cf9c2c7 | 12 | #include <linux/kernel.h> |
15f2e88d MW |
13 | #include <linux/list.h> |
14 | #include <linux/preempt.h> | |
7cf9c2c7 | 15 | #include <linux/rcupdate.h> |
15f2e88d MW |
16 | #include <linux/spinlock.h> |
17 | #include <linux/types.h> | |
3159f943 | 18 | #include <linux/xarray.h> |
7cf9c2c7 | 19 | |
f8d5d0cc MW |
20 | /* Keep unconverted code working */ |
21 | #define radix_tree_root xarray | |
01959dfe | 22 | #define radix_tree_node xa_node |
f8d5d0cc | 23 | |
7cf9c2c7 | 24 | /* |
3bcadd6f MW |
25 | * The bottom two bits of the slot determine how the remaining bits in the |
26 | * slot are interpreted: | |
7cf9c2c7 | 27 | * |
3bcadd6f | 28 | * 00 - data pointer |
3159f943 MW |
29 | * 10 - internal entry |
30 | * x1 - value entry | |
3bcadd6f MW |
31 | * |
32 | * The internal entry may be a pointer to the next level in the tree, a | |
33 | * sibling entry, or an indicator that the entry in this slot has been moved | |
34 | * to another location in the tree and the lookup should be restarted. While | |
35 | * NULL fits the 'data pointer' pattern, it means that there is no entry in | |
36 | * the tree for this index (no matter what level of the tree it is found at). | |
3159f943 MW |
37 | * This means that storing a NULL entry in the tree is the same as deleting |
38 | * the entry from the tree. | |
7cf9c2c7 | 39 | */ |
3bcadd6f | 40 | #define RADIX_TREE_ENTRY_MASK 3UL |
3159f943 | 41 | #define RADIX_TREE_INTERNAL_NODE 2UL |
7cf9c2c7 | 42 | |
3bcadd6f | 43 | static inline bool radix_tree_is_internal_node(void *ptr) |
7cf9c2c7 | 44 | { |
3bcadd6f MW |
45 | return ((unsigned long)ptr & RADIX_TREE_ENTRY_MASK) == |
46 | RADIX_TREE_INTERNAL_NODE; | |
7cf9c2c7 NP |
47 | } |
48 | ||
49 | /*** radix-tree API starts here ***/ | |
1da177e4 | 50 | |
02c02bf1 | 51 | #define RADIX_TREE_MAP_SHIFT XA_CHUNK_SHIFT |
139e5616 JW |
52 | #define RADIX_TREE_MAP_SIZE (1UL << RADIX_TREE_MAP_SHIFT) |
53 | #define RADIX_TREE_MAP_MASK (RADIX_TREE_MAP_SIZE-1) | |
54 | ||
01959dfe MW |
55 | #define RADIX_TREE_MAX_TAGS XA_MAX_MARKS |
56 | #define RADIX_TREE_TAG_LONGS XA_MARK_LONGS | |
139e5616 | 57 | |
449dd698 JW |
58 | #define RADIX_TREE_INDEX_BITS (8 /* CHAR_BIT */ * sizeof(unsigned long)) |
59 | #define RADIX_TREE_MAX_PATH (DIV_ROUND_UP(RADIX_TREE_INDEX_BITS, \ | |
60 | RADIX_TREE_MAP_SHIFT)) | |
61 | ||
f8d5d0cc | 62 | /* The IDR tag is stored in the low bits of xa_flags */ |
fa290cda | 63 | #define ROOT_IS_IDR ((__force gfp_t)4) |
f8d5d0cc | 64 | /* The top bits of xa_flags are used to store the root tags */ |
fa290cda | 65 | #define ROOT_TAG_SHIFT (__GFP_BITS_SHIFT) |
0a835c4f | 66 | |
f8d5d0cc | 67 | #define RADIX_TREE_INIT(name, mask) XARRAY_INIT(name, mask) |
1da177e4 LT |
68 | |
69 | #define RADIX_TREE(name, mask) \ | |
f6bb2a2c | 70 | struct radix_tree_root name = RADIX_TREE_INIT(name, mask) |
1da177e4 | 71 | |
f8d5d0cc | 72 | #define INIT_RADIX_TREE(root, mask) xa_init_flags(root, mask) |
1da177e4 | 73 | |
35534c86 | 74 | static inline bool radix_tree_empty(const struct radix_tree_root *root) |
e9256efc | 75 | { |
f8d5d0cc | 76 | return root->xa_head == NULL; |
e9256efc MW |
77 | } |
78 | ||
268f42de MW |
79 | /** |
80 | * struct radix_tree_iter - radix tree iterator state | |
81 | * | |
82 | * @index: index of current slot | |
83 | * @next_index: one beyond the last index for this chunk | |
84 | * @tags: bit-mask for tag-iterating | |
85 | * @node: node that contains current slot | |
268f42de MW |
86 | * |
87 | * This radix tree iterator works in terms of "chunks" of slots. A chunk is a | |
88 | * subinterval of slots contained within one radix tree leaf node. It is | |
89 | * described by a pointer to its first slot and a struct radix_tree_iter | |
90 | * which holds the chunk's position in the tree and its size. For tagged | |
91 | * iteration radix_tree_iter also holds the slots' bit-mask for one chosen | |
92 | * radix tree tag. | |
93 | */ | |
94 | struct radix_tree_iter { | |
95 | unsigned long index; | |
96 | unsigned long next_index; | |
97 | unsigned long tags; | |
98 | struct radix_tree_node *node; | |
268f42de MW |
99 | }; |
100 | ||
7cf9c2c7 NP |
101 | /** |
102 | * Radix-tree synchronization | |
103 | * | |
104 | * The radix-tree API requires that users provide all synchronisation (with | |
105 | * specific exceptions, noted below). | |
106 | * | |
107 | * Synchronization of access to the data items being stored in the tree, and | |
108 | * management of their lifetimes must be completely managed by API users. | |
109 | * | |
110 | * For API usage, in general, | |
59c51591 | 111 | * - any function _modifying_ the tree or tags (inserting or deleting |
eb8dc5e7 | 112 | * items, setting or clearing tags) must exclude other modifications, and |
7cf9c2c7 | 113 | * exclude any functions reading the tree. |
59c51591 | 114 | * - any function _reading_ the tree or tags (looking up items or tags, |
7cf9c2c7 NP |
115 | * gang lookups) must exclude modifications to the tree, but may occur |
116 | * concurrently with other readers. | |
117 | * | |
118 | * The notable exceptions to this rule are the following functions: | |
139e5616 | 119 | * __radix_tree_lookup |
7cf9c2c7 | 120 | * radix_tree_lookup |
47feff2c | 121 | * radix_tree_lookup_slot |
7cf9c2c7 NP |
122 | * radix_tree_tag_get |
123 | * radix_tree_gang_lookup | |
124 | * radix_tree_gang_lookup_tag | |
47feff2c | 125 | * radix_tree_gang_lookup_tag_slot |
7cf9c2c7 NP |
126 | * radix_tree_tagged |
127 | * | |
7b8d046f | 128 | * The first 7 functions are able to be called locklessly, using RCU. The |
7cf9c2c7 NP |
129 | * caller must ensure calls to these functions are made within rcu_read_lock() |
130 | * regions. Other readers (lock-free or otherwise) and modifications may be | |
131 | * running concurrently. | |
132 | * | |
133 | * It is still required that the caller manage the synchronization and lifetimes | |
134 | * of the items. So if RCU lock-free lookups are used, typically this would mean | |
135 | * that the items have their own locks, or are amenable to lock-free access; and | |
136 | * that the items are freed by RCU (or only freed after having been deleted from | |
137 | * the radix tree *and* a synchronize_rcu() grace period). | |
138 | * | |
139 | * (Note, rcu_assign_pointer and rcu_dereference are not needed to control | |
140 | * access to data items when inserting into or looking up from the radix tree) | |
141 | * | |
ce82653d DH |
142 | * Note that the value returned by radix_tree_tag_get() may not be relied upon |
143 | * if only the RCU read lock is held. Functions to set/clear tags and to | |
144 | * delete nodes running concurrently with it may affect its result such that | |
145 | * two consecutive reads in the same locked section may return different | |
146 | * values. If reliability is required, modification functions must also be | |
147 | * excluded from concurrency. | |
148 | * | |
7cf9c2c7 NP |
149 | * radix_tree_tagged is able to be called without locking or RCU. |
150 | */ | |
151 | ||
152 | /** | |
d7b62727 MW |
153 | * radix_tree_deref_slot - dereference a slot |
154 | * @slot: slot pointer, returned by radix_tree_lookup_slot | |
7cf9c2c7 NP |
155 | * |
156 | * For use with radix_tree_lookup_slot(). Caller must hold tree at least read | |
27d20fdd NP |
157 | * locked across slot lookup and dereference. Not required if write lock is |
158 | * held (ie. items cannot be concurrently inserted). | |
159 | * | |
160 | * radix_tree_deref_retry must be used to confirm validity of the pointer if | |
161 | * only the read lock is held. | |
d7b62727 MW |
162 | * |
163 | * Return: entry stored in that slot. | |
7cf9c2c7 | 164 | */ |
d7b62727 | 165 | static inline void *radix_tree_deref_slot(void __rcu **slot) |
7cf9c2c7 | 166 | { |
d7b62727 | 167 | return rcu_dereference(*slot); |
7cf9c2c7 | 168 | } |
27d20fdd | 169 | |
29c1f677 | 170 | /** |
d7b62727 MW |
171 | * radix_tree_deref_slot_protected - dereference a slot with tree lock held |
172 | * @slot: slot pointer, returned by radix_tree_lookup_slot | |
173 | * | |
174 | * Similar to radix_tree_deref_slot. The caller does not hold the RCU read | |
175 | * lock but it must hold the tree lock to prevent parallel updates. | |
29c1f677 | 176 | * |
d7b62727 | 177 | * Return: entry stored in that slot. |
29c1f677 | 178 | */ |
d7b62727 | 179 | static inline void *radix_tree_deref_slot_protected(void __rcu **slot, |
29c1f677 MG |
180 | spinlock_t *treelock) |
181 | { | |
d7b62727 | 182 | return rcu_dereference_protected(*slot, lockdep_is_held(treelock)); |
29c1f677 MG |
183 | } |
184 | ||
27d20fdd NP |
185 | /** |
186 | * radix_tree_deref_retry - check radix_tree_deref_slot | |
187 | * @arg: pointer returned by radix_tree_deref_slot | |
188 | * Returns: 0 if retry is not required, otherwise retry is required | |
189 | * | |
190 | * radix_tree_deref_retry must be used with radix_tree_deref_slot. | |
191 | */ | |
192 | static inline int radix_tree_deref_retry(void *arg) | |
193 | { | |
b194d16c | 194 | return unlikely(radix_tree_is_internal_node(arg)); |
27d20fdd NP |
195 | } |
196 | ||
6328650b HD |
197 | /** |
198 | * radix_tree_exception - radix_tree_deref_slot returned either exception? | |
199 | * @arg: value returned by radix_tree_deref_slot | |
200 | * Returns: 0 if well-aligned pointer, non-0 if either kind of exception. | |
201 | */ | |
202 | static inline int radix_tree_exception(void *arg) | |
203 | { | |
3bcadd6f | 204 | return unlikely((unsigned long)arg & RADIX_TREE_ENTRY_MASK); |
6328650b HD |
205 | } |
206 | ||
3a08cd52 MW |
207 | int radix_tree_insert(struct radix_tree_root *, unsigned long index, |
208 | void *); | |
35534c86 | 209 | void *__radix_tree_lookup(const struct radix_tree_root *, unsigned long index, |
d7b62727 | 210 | struct radix_tree_node **nodep, void __rcu ***slotp); |
35534c86 | 211 | void *radix_tree_lookup(const struct radix_tree_root *, unsigned long); |
d7b62727 MW |
212 | void __rcu **radix_tree_lookup_slot(const struct radix_tree_root *, |
213 | unsigned long index); | |
d7b62727 | 214 | void __radix_tree_replace(struct radix_tree_root *, struct radix_tree_node *, |
1cf56f9d | 215 | void __rcu **slot, void *entry); |
e157b555 | 216 | void radix_tree_iter_replace(struct radix_tree_root *, |
d7b62727 MW |
217 | const struct radix_tree_iter *, void __rcu **slot, void *entry); |
218 | void radix_tree_replace_slot(struct radix_tree_root *, | |
219 | void __rcu **slot, void *entry); | |
0ac398ef | 220 | void radix_tree_iter_delete(struct radix_tree_root *, |
d7b62727 | 221 | struct radix_tree_iter *iter, void __rcu **slot); |
53c59f26 | 222 | void *radix_tree_delete_item(struct radix_tree_root *, unsigned long, void *); |
1da177e4 | 223 | void *radix_tree_delete(struct radix_tree_root *, unsigned long); |
35534c86 | 224 | unsigned int radix_tree_gang_lookup(const struct radix_tree_root *, |
d604c324 MW |
225 | void **results, unsigned long first_index, |
226 | unsigned int max_items); | |
dd0fc66f | 227 | int radix_tree_preload(gfp_t gfp_mask); |
5e4c0d97 | 228 | int radix_tree_maybe_preload(gfp_t gfp_mask); |
1da177e4 | 229 | void radix_tree_init(void); |
d7b62727 | 230 | void *radix_tree_tag_set(struct radix_tree_root *, |
daff89f3 | 231 | unsigned long index, unsigned int tag); |
d7b62727 | 232 | void *radix_tree_tag_clear(struct radix_tree_root *, |
daff89f3 | 233 | unsigned long index, unsigned int tag); |
35534c86 | 234 | int radix_tree_tag_get(const struct radix_tree_root *, |
daff89f3 | 235 | unsigned long index, unsigned int tag); |
30b888ba | 236 | void radix_tree_iter_tag_clear(struct radix_tree_root *, |
268f42de | 237 | const struct radix_tree_iter *iter, unsigned int tag); |
d7b62727 MW |
238 | unsigned int radix_tree_gang_lookup_tag(const struct radix_tree_root *, |
239 | void **results, unsigned long first_index, | |
240 | unsigned int max_items, unsigned int tag); | |
241 | unsigned int radix_tree_gang_lookup_tag_slot(const struct radix_tree_root *, | |
242 | void __rcu ***results, unsigned long first_index, | |
243 | unsigned int max_items, unsigned int tag); | |
244 | int radix_tree_tagged(const struct radix_tree_root *, unsigned int tag); | |
1da177e4 LT |
245 | |
246 | static inline void radix_tree_preload_end(void) | |
247 | { | |
248 | preempt_enable(); | |
249 | } | |
250 | ||
460488c5 | 251 | void __rcu **idr_get_free(struct radix_tree_root *root, |
388f79fd CM |
252 | struct radix_tree_iter *iter, gfp_t gfp, |
253 | unsigned long max); | |
175542f5 | 254 | |
0a835c4f MW |
255 | enum { |
256 | RADIX_TREE_ITER_TAG_MASK = 0x0f, /* tag index in lower nybble */ | |
257 | RADIX_TREE_ITER_TAGGED = 0x10, /* lookup tagged slots */ | |
258 | RADIX_TREE_ITER_CONTIG = 0x20, /* stop at first hole */ | |
259 | }; | |
78c1d784 KK |
260 | |
261 | /** | |
262 | * radix_tree_iter_init - initialize radix tree iterator | |
263 | * | |
264 | * @iter: pointer to iterator state | |
265 | * @start: iteration starting index | |
266 | * Returns: NULL | |
267 | */ | |
d7b62727 | 268 | static __always_inline void __rcu ** |
78c1d784 KK |
269 | radix_tree_iter_init(struct radix_tree_iter *iter, unsigned long start) |
270 | { | |
271 | /* | |
272 | * Leave iter->tags uninitialized. radix_tree_next_chunk() will fill it | |
273 | * in the case of a successful tagged chunk lookup. If the lookup was | |
274 | * unsuccessful or non-tagged then nobody cares about ->tags. | |
275 | * | |
276 | * Set index to zero to bypass next_index overflow protection. | |
277 | * See the comment in radix_tree_next_chunk() for details. | |
278 | */ | |
279 | iter->index = 0; | |
280 | iter->next_index = start; | |
281 | return NULL; | |
282 | } | |
283 | ||
284 | /** | |
285 | * radix_tree_next_chunk - find next chunk of slots for iteration | |
286 | * | |
287 | * @root: radix tree root | |
288 | * @iter: iterator state | |
289 | * @flags: RADIX_TREE_ITER_* flags and tag index | |
290 | * Returns: pointer to chunk first slot, or NULL if there no more left | |
291 | * | |
292 | * This function looks up the next chunk in the radix tree starting from | |
293 | * @iter->next_index. It returns a pointer to the chunk's first slot. | |
294 | * Also it fills @iter with data about chunk: position in the tree (index), | |
295 | * its end (next_index), and constructs a bit mask for tagged iterating (tags). | |
296 | */ | |
d7b62727 | 297 | void __rcu **radix_tree_next_chunk(const struct radix_tree_root *, |
78c1d784 KK |
298 | struct radix_tree_iter *iter, unsigned flags); |
299 | ||
0a835c4f MW |
300 | /** |
301 | * radix_tree_iter_lookup - look up an index in the radix tree | |
302 | * @root: radix tree root | |
303 | * @iter: iterator state | |
304 | * @index: key to look up | |
305 | * | |
306 | * If @index is present in the radix tree, this function returns the slot | |
307 | * containing it and updates @iter to describe the entry. If @index is not | |
308 | * present, it returns NULL. | |
309 | */ | |
d7b62727 MW |
310 | static inline void __rcu ** |
311 | radix_tree_iter_lookup(const struct radix_tree_root *root, | |
0a835c4f MW |
312 | struct radix_tree_iter *iter, unsigned long index) |
313 | { | |
314 | radix_tree_iter_init(iter, index); | |
315 | return radix_tree_next_chunk(root, iter, RADIX_TREE_ITER_CONTIG); | |
316 | } | |
317 | ||
318 | /** | |
319 | * radix_tree_iter_find - find a present entry | |
320 | * @root: radix tree root | |
321 | * @iter: iterator state | |
322 | * @index: start location | |
323 | * | |
324 | * This function returns the slot containing the entry with the lowest index | |
325 | * which is at least @index. If @index is larger than any present entry, this | |
326 | * function returns NULL. The @iter is updated to describe the entry found. | |
327 | */ | |
d7b62727 MW |
328 | static inline void __rcu ** |
329 | radix_tree_iter_find(const struct radix_tree_root *root, | |
0a835c4f MW |
330 | struct radix_tree_iter *iter, unsigned long index) |
331 | { | |
332 | radix_tree_iter_init(iter, index); | |
333 | return radix_tree_next_chunk(root, iter, 0); | |
334 | } | |
335 | ||
46437f9a MW |
336 | /** |
337 | * radix_tree_iter_retry - retry this chunk of the iteration | |
338 | * @iter: iterator state | |
339 | * | |
340 | * If we iterate over a tree protected only by the RCU lock, a race | |
341 | * against deletion or creation may result in seeing a slot for which | |
342 | * radix_tree_deref_retry() returns true. If so, call this function | |
343 | * and continue the iteration. | |
344 | */ | |
345 | static inline __must_check | |
d7b62727 | 346 | void __rcu **radix_tree_iter_retry(struct radix_tree_iter *iter) |
46437f9a MW |
347 | { |
348 | iter->next_index = iter->index; | |
3cb9185c | 349 | iter->tags = 0; |
46437f9a MW |
350 | return NULL; |
351 | } | |
352 | ||
21ef5339 RZ |
353 | static inline unsigned long |
354 | __radix_tree_iter_add(struct radix_tree_iter *iter, unsigned long slots) | |
355 | { | |
3a08cd52 | 356 | return iter->index + slots; |
21ef5339 RZ |
357 | } |
358 | ||
7165092f | 359 | /** |
148deab2 MW |
360 | * radix_tree_iter_resume - resume iterating when the chunk may be invalid |
361 | * @slot: pointer to current slot | |
362 | * @iter: iterator state | |
363 | * Returns: New slot pointer | |
7165092f MW |
364 | * |
365 | * If the iterator needs to release then reacquire a lock, the chunk may | |
366 | * have been invalidated by an insertion or deletion. Call this function | |
148deab2 | 367 | * before releasing the lock to continue the iteration from the next index. |
7165092f | 368 | */ |
d7b62727 | 369 | void __rcu **__must_check radix_tree_iter_resume(void __rcu **slot, |
148deab2 | 370 | struct radix_tree_iter *iter); |
7165092f | 371 | |
78c1d784 KK |
372 | /** |
373 | * radix_tree_chunk_size - get current chunk size | |
374 | * | |
375 | * @iter: pointer to radix tree iterator | |
376 | * Returns: current chunk size | |
377 | */ | |
73204282 | 378 | static __always_inline long |
78c1d784 KK |
379 | radix_tree_chunk_size(struct radix_tree_iter *iter) |
380 | { | |
3a08cd52 | 381 | return iter->next_index - iter->index; |
78c1d784 KK |
382 | } |
383 | ||
384 | /** | |
385 | * radix_tree_next_slot - find next slot in chunk | |
386 | * | |
387 | * @slot: pointer to current slot | |
388 | * @iter: pointer to interator state | |
389 | * @flags: RADIX_TREE_ITER_*, should be constant | |
390 | * Returns: pointer to next slot, or NULL if there no more left | |
391 | * | |
392 | * This function updates @iter->index in the case of a successful lookup. | |
393 | * For tagged lookup it also eats @iter->tags. | |
915045fe RZ |
394 | * |
395 | * There are several cases where 'slot' can be passed in as NULL to this | |
148deab2 | 396 | * function. These cases result from the use of radix_tree_iter_resume() or |
915045fe RZ |
397 | * radix_tree_iter_retry(). In these cases we don't end up dereferencing |
398 | * 'slot' because either: | |
399 | * a) we are doing tagged iteration and iter->tags has been set to 0, or | |
400 | * b) we are doing non-tagged iteration, and iter->index and iter->next_index | |
401 | * have been set up so that radix_tree_chunk_size() returns 1 or 0. | |
78c1d784 | 402 | */ |
d7b62727 MW |
403 | static __always_inline void __rcu **radix_tree_next_slot(void __rcu **slot, |
404 | struct radix_tree_iter *iter, unsigned flags) | |
78c1d784 KK |
405 | { |
406 | if (flags & RADIX_TREE_ITER_TAGGED) { | |
407 | iter->tags >>= 1; | |
21ef5339 RZ |
408 | if (unlikely(!iter->tags)) |
409 | return NULL; | |
78c1d784 | 410 | if (likely(iter->tags & 1ul)) { |
21ef5339 | 411 | iter->index = __radix_tree_iter_add(iter, 1); |
148deab2 MW |
412 | slot++; |
413 | goto found; | |
78c1d784 | 414 | } |
21ef5339 | 415 | if (!(flags & RADIX_TREE_ITER_CONTIG)) { |
78c1d784 KK |
416 | unsigned offset = __ffs(iter->tags); |
417 | ||
148deab2 MW |
418 | iter->tags >>= offset++; |
419 | iter->index = __radix_tree_iter_add(iter, offset); | |
420 | slot += offset; | |
421 | goto found; | |
78c1d784 KK |
422 | } |
423 | } else { | |
21ef5339 | 424 | long count = radix_tree_chunk_size(iter); |
78c1d784 | 425 | |
21ef5339 | 426 | while (--count > 0) { |
78c1d784 | 427 | slot++; |
21ef5339 RZ |
428 | iter->index = __radix_tree_iter_add(iter, 1); |
429 | ||
78c1d784 | 430 | if (likely(*slot)) |
148deab2 | 431 | goto found; |
fffaee36 KK |
432 | if (flags & RADIX_TREE_ITER_CONTIG) { |
433 | /* forbid switching to the next chunk */ | |
434 | iter->next_index = 0; | |
78c1d784 | 435 | break; |
fffaee36 | 436 | } |
78c1d784 KK |
437 | } |
438 | } | |
439 | return NULL; | |
148deab2 MW |
440 | |
441 | found: | |
148deab2 | 442 | return slot; |
78c1d784 KK |
443 | } |
444 | ||
78c1d784 KK |
445 | /** |
446 | * radix_tree_for_each_slot - iterate over non-empty slots | |
447 | * | |
448 | * @slot: the void** variable for pointer to slot | |
449 | * @root: the struct radix_tree_root pointer | |
450 | * @iter: the struct radix_tree_iter pointer | |
451 | * @start: iteration starting index | |
452 | * | |
453 | * @slot points to radix tree slot, @iter->index contains its index. | |
454 | */ | |
455 | #define radix_tree_for_each_slot(slot, root, iter, start) \ | |
456 | for (slot = radix_tree_iter_init(iter, start) ; \ | |
457 | slot || (slot = radix_tree_next_chunk(root, iter, 0)) ; \ | |
458 | slot = radix_tree_next_slot(slot, iter, 0)) | |
459 | ||
78c1d784 KK |
460 | /** |
461 | * radix_tree_for_each_tagged - iterate over tagged slots | |
462 | * | |
463 | * @slot: the void** variable for pointer to slot | |
464 | * @root: the struct radix_tree_root pointer | |
465 | * @iter: the struct radix_tree_iter pointer | |
466 | * @start: iteration starting index | |
467 | * @tag: tag index | |
468 | * | |
469 | * @slot points to radix tree slot, @iter->index contains its index. | |
470 | */ | |
471 | #define radix_tree_for_each_tagged(slot, root, iter, start, tag) \ | |
472 | for (slot = radix_tree_iter_init(iter, start) ; \ | |
473 | slot || (slot = radix_tree_next_chunk(root, iter, \ | |
474 | RADIX_TREE_ITER_TAGGED | tag)) ; \ | |
475 | slot = radix_tree_next_slot(slot, iter, \ | |
148deab2 | 476 | RADIX_TREE_ITER_TAGGED | tag)) |
78c1d784 | 477 | |
1da177e4 | 478 | #endif /* _LINUX_RADIX_TREE_H */ |