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authorDavid S. Miller <davem@davemloft.net>2019-01-27 13:43:17 -0500
committerDavid S. Miller <davem@davemloft.net>2019-01-27 13:43:17 -0500
commit1d68101367a92336e633d0c3681bf8c86644e124 (patch)
tree8fdacef561481c25c71641b8fa91a5dfa0ba7f96 /include/linux/xarray.h
parent085c4c7dd2b6558fb079fad07d6e9064f5e0b4c2 (diff)
parent1fc7f56db7a7c467e46a5d2e2a009d2f337e0338 (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Diffstat (limited to 'include/linux/xarray.h')
-rw-r--r--include/linux/xarray.h227
1 files changed, 170 insertions, 57 deletions
diff --git a/include/linux/xarray.h b/include/linux/xarray.h
index f492e21c4aa2..5d9d318bcf7a 100644
--- a/include/linux/xarray.h
+++ b/include/linux/xarray.h
@@ -176,7 +176,8 @@ static inline bool xa_is_internal(const void *entry)
176 */ 176 */
177static inline bool xa_is_err(const void *entry) 177static inline bool xa_is_err(const void *entry)
178{ 178{
179 return unlikely(xa_is_internal(entry)); 179 return unlikely(xa_is_internal(entry) &&
180 entry >= xa_mk_internal(-MAX_ERRNO));
180} 181}
181 182
182/** 183/**
@@ -286,7 +287,6 @@ struct xarray {
286 */ 287 */
287#define DEFINE_XARRAY_ALLOC(name) DEFINE_XARRAY_FLAGS(name, XA_FLAGS_ALLOC) 288#define DEFINE_XARRAY_ALLOC(name) DEFINE_XARRAY_FLAGS(name, XA_FLAGS_ALLOC)
288 289
289void xa_init_flags(struct xarray *, gfp_t flags);
290void *xa_load(struct xarray *, unsigned long index); 290void *xa_load(struct xarray *, unsigned long index);
291void *xa_store(struct xarray *, unsigned long index, void *entry, gfp_t); 291void *xa_store(struct xarray *, unsigned long index, void *entry, gfp_t);
292void *xa_erase(struct xarray *, unsigned long index); 292void *xa_erase(struct xarray *, unsigned long index);
@@ -304,6 +304,24 @@ unsigned int xa_extract(struct xarray *, void **dst, unsigned long start,
304void xa_destroy(struct xarray *); 304void xa_destroy(struct xarray *);
305 305
306/** 306/**
307 * xa_init_flags() - Initialise an empty XArray with flags.
308 * @xa: XArray.
309 * @flags: XA_FLAG values.
310 *
311 * If you need to initialise an XArray with special flags (eg you need
312 * to take the lock from interrupt context), use this function instead
313 * of xa_init().
314 *
315 * Context: Any context.
316 */
317static inline void xa_init_flags(struct xarray *xa, gfp_t flags)
318{
319 spin_lock_init(&xa->xa_lock);
320 xa->xa_flags = flags;
321 xa->xa_head = NULL;
322}
323
324/**
307 * xa_init() - Initialise an empty XArray. 325 * xa_init() - Initialise an empty XArray.
308 * @xa: XArray. 326 * @xa: XArray.
309 * 327 *
@@ -342,20 +360,45 @@ static inline bool xa_marked(const struct xarray *xa, xa_mark_t mark)
342} 360}
343 361
344/** 362/**
345 * xa_for_each() - Iterate over a portion of an XArray. 363 * xa_for_each_start() - Iterate over a portion of an XArray.
346 * @xa: XArray. 364 * @xa: XArray.
365 * @index: Index of @entry.
347 * @entry: Entry retrieved from array. 366 * @entry: Entry retrieved from array.
367 * @start: First index to retrieve from array.
368 *
369 * During the iteration, @entry will have the value of the entry stored
370 * in @xa at @index. You may modify @index during the iteration if you
371 * want to skip or reprocess indices. It is safe to modify the array
372 * during the iteration. At the end of the iteration, @entry will be set
373 * to NULL and @index will have a value less than or equal to max.
374 *
375 * xa_for_each_start() is O(n.log(n)) while xas_for_each() is O(n). You have
376 * to handle your own locking with xas_for_each(), and if you have to unlock
377 * after each iteration, it will also end up being O(n.log(n)).
378 * xa_for_each_start() will spin if it hits a retry entry; if you intend to
379 * see retry entries, you should use the xas_for_each() iterator instead.
380 * The xas_for_each() iterator will expand into more inline code than
381 * xa_for_each_start().
382 *
383 * Context: Any context. Takes and releases the RCU lock.
384 */
385#define xa_for_each_start(xa, index, entry, start) \
386 for (index = start, \
387 entry = xa_find(xa, &index, ULONG_MAX, XA_PRESENT); \
388 entry; \
389 entry = xa_find_after(xa, &index, ULONG_MAX, XA_PRESENT))
390
391/**
392 * xa_for_each() - Iterate over present entries in an XArray.
393 * @xa: XArray.
348 * @index: Index of @entry. 394 * @index: Index of @entry.
349 * @max: Maximum index to retrieve from array. 395 * @entry: Entry retrieved from array.
350 * @filter: Selection criterion.
351 * 396 *
352 * Initialise @index to the lowest index you want to retrieve from the 397 * During the iteration, @entry will have the value of the entry stored
353 * array. During the iteration, @entry will have the value of the entry 398 * in @xa at @index. You may modify @index during the iteration if you want
354 * stored in @xa at @index. The iteration will skip all entries in the 399 * to skip or reprocess indices. It is safe to modify the array during the
355 * array which do not match @filter. You may modify @index during the 400 * iteration. At the end of the iteration, @entry will be set to NULL and
356 * iteration if you want to skip or reprocess indices. It is safe to modify 401 * @index will have a value less than or equal to max.
357 * the array during the iteration. At the end of the iteration, @entry will
358 * be set to NULL and @index will have a value less than or equal to max.
359 * 402 *
360 * xa_for_each() is O(n.log(n)) while xas_for_each() is O(n). You have 403 * xa_for_each() is O(n.log(n)) while xas_for_each() is O(n). You have
361 * to handle your own locking with xas_for_each(), and if you have to unlock 404 * to handle your own locking with xas_for_each(), and if you have to unlock
@@ -366,9 +409,36 @@ static inline bool xa_marked(const struct xarray *xa, xa_mark_t mark)
366 * 409 *
367 * Context: Any context. Takes and releases the RCU lock. 410 * Context: Any context. Takes and releases the RCU lock.
368 */ 411 */
369#define xa_for_each(xa, entry, index, max, filter) \ 412#define xa_for_each(xa, index, entry) \
370 for (entry = xa_find(xa, &index, max, filter); entry; \ 413 xa_for_each_start(xa, index, entry, 0)
371 entry = xa_find_after(xa, &index, max, filter)) 414
415/**
416 * xa_for_each_marked() - Iterate over marked entries in an XArray.
417 * @xa: XArray.
418 * @index: Index of @entry.
419 * @entry: Entry retrieved from array.
420 * @filter: Selection criterion.
421 *
422 * During the iteration, @entry will have the value of the entry stored
423 * in @xa at @index. The iteration will skip all entries in the array
424 * which do not match @filter. You may modify @index during the iteration
425 * if you want to skip or reprocess indices. It is safe to modify the array
426 * during the iteration. At the end of the iteration, @entry will be set to
427 * NULL and @index will have a value less than or equal to max.
428 *
429 * xa_for_each_marked() is O(n.log(n)) while xas_for_each_marked() is O(n).
430 * You have to handle your own locking with xas_for_each(), and if you have
431 * to unlock after each iteration, it will also end up being O(n.log(n)).
432 * xa_for_each_marked() will spin if it hits a retry entry; if you intend to
433 * see retry entries, you should use the xas_for_each_marked() iterator
434 * instead. The xas_for_each_marked() iterator will expand into more inline
435 * code than xa_for_each_marked().
436 *
437 * Context: Any context. Takes and releases the RCU lock.
438 */
439#define xa_for_each_marked(xa, index, entry, filter) \
440 for (index = 0, entry = xa_find(xa, &index, ULONG_MAX, filter); \
441 entry; entry = xa_find_after(xa, &index, ULONG_MAX, filter))
372 442
373#define xa_trylock(xa) spin_trylock(&(xa)->xa_lock) 443#define xa_trylock(xa) spin_trylock(&(xa)->xa_lock)
374#define xa_lock(xa) spin_lock(&(xa)->xa_lock) 444#define xa_lock(xa) spin_lock(&(xa)->xa_lock)
@@ -393,40 +463,13 @@ void *__xa_erase(struct xarray *, unsigned long index);
393void *__xa_store(struct xarray *, unsigned long index, void *entry, gfp_t); 463void *__xa_store(struct xarray *, unsigned long index, void *entry, gfp_t);
394void *__xa_cmpxchg(struct xarray *, unsigned long index, void *old, 464void *__xa_cmpxchg(struct xarray *, unsigned long index, void *old,
395 void *entry, gfp_t); 465 void *entry, gfp_t);
466int __xa_insert(struct xarray *, unsigned long index, void *entry, gfp_t);
396int __xa_alloc(struct xarray *, u32 *id, u32 max, void *entry, gfp_t); 467int __xa_alloc(struct xarray *, u32 *id, u32 max, void *entry, gfp_t);
397int __xa_reserve(struct xarray *, unsigned long index, gfp_t); 468int __xa_reserve(struct xarray *, unsigned long index, gfp_t);
398void __xa_set_mark(struct xarray *, unsigned long index, xa_mark_t); 469void __xa_set_mark(struct xarray *, unsigned long index, xa_mark_t);
399void __xa_clear_mark(struct xarray *, unsigned long index, xa_mark_t); 470void __xa_clear_mark(struct xarray *, unsigned long index, xa_mark_t);
400 471
401/** 472/**
402 * __xa_insert() - Store this entry in the XArray unless another entry is
403 * already present.
404 * @xa: XArray.
405 * @index: Index into array.
406 * @entry: New entry.
407 * @gfp: Memory allocation flags.
408 *
409 * If you would rather see the existing entry in the array, use __xa_cmpxchg().
410 * This function is for users who don't care what the entry is, only that
411 * one is present.
412 *
413 * Context: Any context. Expects xa_lock to be held on entry. May
414 * release and reacquire xa_lock if the @gfp flags permit.
415 * Return: 0 if the store succeeded. -EEXIST if another entry was present.
416 * -ENOMEM if memory could not be allocated.
417 */
418static inline int __xa_insert(struct xarray *xa, unsigned long index,
419 void *entry, gfp_t gfp)
420{
421 void *curr = __xa_cmpxchg(xa, index, NULL, entry, gfp);
422 if (!curr)
423 return 0;
424 if (xa_is_err(curr))
425 return xa_err(curr);
426 return -EEXIST;
427}
428
429/**
430 * xa_store_bh() - Store this entry in the XArray. 473 * xa_store_bh() - Store this entry in the XArray.
431 * @xa: XArray. 474 * @xa: XArray.
432 * @index: Index into array. 475 * @index: Index into array.
@@ -453,7 +496,7 @@ static inline void *xa_store_bh(struct xarray *xa, unsigned long index,
453} 496}
454 497
455/** 498/**
456 * xa_store_irq() - Erase this entry from the XArray. 499 * xa_store_irq() - Store this entry in the XArray.
457 * @xa: XArray. 500 * @xa: XArray.
458 * @index: Index into array. 501 * @index: Index into array.
459 * @entry: New entry. 502 * @entry: New entry.
@@ -615,24 +658,83 @@ static inline void *xa_cmpxchg_irq(struct xarray *xa, unsigned long index,
615 * @entry: New entry. 658 * @entry: New entry.
616 * @gfp: Memory allocation flags. 659 * @gfp: Memory allocation flags.
617 * 660 *
618 * If you would rather see the existing entry in the array, use xa_cmpxchg(). 661 * Inserting a NULL entry will store a reserved entry (like xa_reserve())
619 * This function is for users who don't care what the entry is, only that 662 * if no entry is present. Inserting will fail if a reserved entry is
620 * one is present. 663 * present, even though loading from this index will return NULL.
621 * 664 *
622 * Context: Process context. Takes and releases the xa_lock. 665 * Context: Any context. Takes and releases the xa_lock. May sleep if
623 * May sleep if the @gfp flags permit. 666 * the @gfp flags permit.
624 * Return: 0 if the store succeeded. -EEXIST if another entry was present. 667 * Return: 0 if the store succeeded. -EEXIST if another entry was present.
625 * -ENOMEM if memory could not be allocated. 668 * -ENOMEM if memory could not be allocated.
626 */ 669 */
627static inline int xa_insert(struct xarray *xa, unsigned long index, 670static inline int xa_insert(struct xarray *xa, unsigned long index,
628 void *entry, gfp_t gfp) 671 void *entry, gfp_t gfp)
629{ 672{
630 void *curr = xa_cmpxchg(xa, index, NULL, entry, gfp); 673 int err;
631 if (!curr) 674
632 return 0; 675 xa_lock(xa);
633 if (xa_is_err(curr)) 676 err = __xa_insert(xa, index, entry, gfp);
634 return xa_err(curr); 677 xa_unlock(xa);
635 return -EEXIST; 678
679 return err;
680}
681
682/**
683 * xa_insert_bh() - Store this entry in the XArray unless another entry is
684 * already present.
685 * @xa: XArray.
686 * @index: Index into array.
687 * @entry: New entry.
688 * @gfp: Memory allocation flags.
689 *
690 * Inserting a NULL entry will store a reserved entry (like xa_reserve())
691 * if no entry is present. Inserting will fail if a reserved entry is
692 * present, even though loading from this index will return NULL.
693 *
694 * Context: Any context. Takes and releases the xa_lock while
695 * disabling softirqs. May sleep if the @gfp flags permit.
696 * Return: 0 if the store succeeded. -EEXIST if another entry was present.
697 * -ENOMEM if memory could not be allocated.
698 */
699static inline int xa_insert_bh(struct xarray *xa, unsigned long index,
700 void *entry, gfp_t gfp)
701{
702 int err;
703
704 xa_lock_bh(xa);
705 err = __xa_insert(xa, index, entry, gfp);
706 xa_unlock_bh(xa);
707
708 return err;
709}
710
711/**
712 * xa_insert_irq() - Store this entry in the XArray unless another entry is
713 * already present.
714 * @xa: XArray.
715 * @index: Index into array.
716 * @entry: New entry.
717 * @gfp: Memory allocation flags.
718 *
719 * Inserting a NULL entry will store a reserved entry (like xa_reserve())
720 * if no entry is present. Inserting will fail if a reserved entry is
721 * present, even though loading from this index will return NULL.
722 *
723 * Context: Process context. Takes and releases the xa_lock while
724 * disabling interrupts. May sleep if the @gfp flags permit.
725 * Return: 0 if the store succeeded. -EEXIST if another entry was present.
726 * -ENOMEM if memory could not be allocated.
727 */
728static inline int xa_insert_irq(struct xarray *xa, unsigned long index,
729 void *entry, gfp_t gfp)
730{
731 int err;
732
733 xa_lock_irq(xa);
734 err = __xa_insert(xa, index, entry, gfp);
735 xa_unlock_irq(xa);
736
737 return err;
636} 738}
637 739
638/** 740/**
@@ -970,8 +1072,8 @@ static inline bool xa_is_sibling(const void *entry)
970 (entry < xa_mk_sibling(XA_CHUNK_SIZE - 1)); 1072 (entry < xa_mk_sibling(XA_CHUNK_SIZE - 1));
971} 1073}
972 1074
973#define XA_ZERO_ENTRY xa_mk_internal(256) 1075#define XA_RETRY_ENTRY xa_mk_internal(256)
974#define XA_RETRY_ENTRY xa_mk_internal(257) 1076#define XA_ZERO_ENTRY xa_mk_internal(257)
975 1077
976/** 1078/**
977 * xa_is_zero() - Is the entry a zero entry? 1079 * xa_is_zero() - Is the entry a zero entry?
@@ -996,6 +1098,17 @@ static inline bool xa_is_retry(const void *entry)
996} 1098}
997 1099
998/** 1100/**
1101 * xa_is_advanced() - Is the entry only permitted for the advanced API?
1102 * @entry: Entry to be stored in the XArray.
1103 *
1104 * Return: %true if the entry cannot be stored by the normal API.
1105 */
1106static inline bool xa_is_advanced(const void *entry)
1107{
1108 return xa_is_internal(entry) && (entry <= XA_RETRY_ENTRY);
1109}
1110
1111/**
999 * typedef xa_update_node_t - A callback function from the XArray. 1112 * typedef xa_update_node_t - A callback function from the XArray.
1000 * @node: The node which is being processed 1113 * @node: The node which is being processed
1001 * 1114 *