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-rw-r--r--lib/idr.c78
1 files changed, 41 insertions, 37 deletions
diff --git a/lib/idr.c b/lib/idr.c
index 7f1a4f0acf50..e15502e8b21e 100644
--- a/lib/idr.c
+++ b/lib/idr.c
@@ -106,16 +106,17 @@ static void idr_mark_full(struct idr_layer **pa, int id)
106} 106}
107 107
108/** 108/**
109 * idr_pre_get - reserver resources for idr allocation 109 * idr_pre_get - reserve resources for idr allocation
110 * @idp: idr handle 110 * @idp: idr handle
111 * @gfp_mask: memory allocation flags 111 * @gfp_mask: memory allocation flags
112 * 112 *
113 * This function should be called prior to locking and calling the 113 * This function should be called prior to calling the idr_get_new* functions.
114 * idr_get_new* functions. It preallocates enough memory to satisfy 114 * It preallocates enough memory to satisfy the worst possible allocation. The
115 * the worst possible allocation. 115 * caller should pass in GFP_KERNEL if possible. This of course requires that
116 * no spinning locks be held.
116 * 117 *
117 * If the system is REALLY out of memory this function returns 0, 118 * If the system is REALLY out of memory this function returns %0,
118 * otherwise 1. 119 * otherwise %1.
119 */ 120 */
120int idr_pre_get(struct idr *idp, gfp_t gfp_mask) 121int idr_pre_get(struct idr *idp, gfp_t gfp_mask)
121{ 122{
@@ -284,17 +285,19 @@ static int idr_get_new_above_int(struct idr *idp, void *ptr, int starting_id)
284 * idr_get_new_above - allocate new idr entry above or equal to a start id 285 * idr_get_new_above - allocate new idr entry above or equal to a start id
285 * @idp: idr handle 286 * @idp: idr handle
286 * @ptr: pointer you want associated with the id 287 * @ptr: pointer you want associated with the id
287 * @start_id: id to start search at 288 * @starting_id: id to start search at
288 * @id: pointer to the allocated handle 289 * @id: pointer to the allocated handle
289 * 290 *
290 * This is the allocate id function. It should be called with any 291 * This is the allocate id function. It should be called with any
291 * required locks. 292 * required locks.
292 * 293 *
293 * If memory is required, it will return -EAGAIN, you should unlock 294 * If allocation from IDR's private freelist fails, idr_get_new_above() will
294 * and go back to the idr_pre_get() call. If the idr is full, it will 295 * return %-EAGAIN. The caller should retry the idr_pre_get() call to refill
295 * return -ENOSPC. 296 * IDR's preallocation and then retry the idr_get_new_above() call.
297 *
298 * If the idr is full idr_get_new_above() will return %-ENOSPC.
296 * 299 *
297 * @id returns a value in the range @starting_id ... 0x7fffffff 300 * @id returns a value in the range @starting_id ... %0x7fffffff
298 */ 301 */
299int idr_get_new_above(struct idr *idp, void *ptr, int starting_id, int *id) 302int idr_get_new_above(struct idr *idp, void *ptr, int starting_id, int *id)
300{ 303{
@@ -318,14 +321,13 @@ EXPORT_SYMBOL(idr_get_new_above);
318 * @ptr: pointer you want associated with the id 321 * @ptr: pointer you want associated with the id
319 * @id: pointer to the allocated handle 322 * @id: pointer to the allocated handle
320 * 323 *
321 * This is the allocate id function. It should be called with any 324 * If allocation from IDR's private freelist fails, idr_get_new_above() will
322 * required locks. 325 * return %-EAGAIN. The caller should retry the idr_pre_get() call to refill
326 * IDR's preallocation and then retry the idr_get_new_above() call.
323 * 327 *
324 * If memory is required, it will return -EAGAIN, you should unlock 328 * If the idr is full idr_get_new_above() will return %-ENOSPC.
325 * and go back to the idr_pre_get() call. If the idr is full, it will
326 * return -ENOSPC.
327 * 329 *
328 * @id returns a value in the range 0 ... 0x7fffffff 330 * @id returns a value in the range %0 ... %0x7fffffff
329 */ 331 */
330int idr_get_new(struct idr *idp, void *ptr, int *id) 332int idr_get_new(struct idr *idp, void *ptr, int *id)
331{ 333{
@@ -388,7 +390,7 @@ static void sub_remove(struct idr *idp, int shift, int id)
388} 390}
389 391
390/** 392/**
391 * idr_remove - remove the given id and free it's slot 393 * idr_remove - remove the given id and free its slot
392 * @idp: idr handle 394 * @idp: idr handle
393 * @id: unique key 395 * @id: unique key
394 */ 396 */
@@ -437,7 +439,7 @@ EXPORT_SYMBOL(idr_remove);
437 * function will remove all id mappings and leave all idp_layers 439 * function will remove all id mappings and leave all idp_layers
438 * unused. 440 * unused.
439 * 441 *
440 * A typical clean-up sequence for objects stored in an idr tree, will 442 * A typical clean-up sequence for objects stored in an idr tree will
441 * use idr_for_each() to free all objects, if necessay, then 443 * use idr_for_each() to free all objects, if necessay, then
442 * idr_remove_all() to remove all ids, and idr_destroy() to free 444 * idr_remove_all() to remove all ids, and idr_destroy() to free
443 * up the cached idr_layers. 445 * up the cached idr_layers.
@@ -479,7 +481,7 @@ EXPORT_SYMBOL(idr_remove_all);
479 481
480/** 482/**
481 * idr_destroy - release all cached layers within an idr tree 483 * idr_destroy - release all cached layers within an idr tree
482 * idp: idr handle 484 * @idp: idr handle
483 */ 485 */
484void idr_destroy(struct idr *idp) 486void idr_destroy(struct idr *idp)
485{ 487{
@@ -542,7 +544,7 @@ EXPORT_SYMBOL(idr_find);
542 * not allowed. 544 * not allowed.
543 * 545 *
544 * We check the return of @fn each time. If it returns anything other 546 * We check the return of @fn each time. If it returns anything other
545 * than 0, we break out and return that value. 547 * than %0, we break out and return that value.
546 * 548 *
547 * The caller must serialize idr_for_each() vs idr_get_new() and idr_remove(). 549 * The caller must serialize idr_for_each() vs idr_get_new() and idr_remove().
548 */ 550 */
@@ -586,10 +588,11 @@ EXPORT_SYMBOL(idr_for_each);
586/** 588/**
587 * idr_get_next - lookup next object of id to given id. 589 * idr_get_next - lookup next object of id to given id.
588 * @idp: idr handle 590 * @idp: idr handle
589 * @id: pointer to lookup key 591 * @nextidp: pointer to lookup key
590 * 592 *
591 * Returns pointer to registered object with id, which is next number to 593 * Returns pointer to registered object with id, which is next number to
592 * given id. 594 * given id. After being looked up, *@nextidp will be updated for the next
595 * iteration.
593 */ 596 */
594 597
595void *idr_get_next(struct idr *idp, int *nextidp) 598void *idr_get_next(struct idr *idp, int *nextidp)
@@ -636,8 +639,8 @@ EXPORT_SYMBOL(idr_get_next);
636 * @id: lookup key 639 * @id: lookup key
637 * 640 *
638 * Replace the pointer registered with an id and return the old value. 641 * Replace the pointer registered with an id and return the old value.
639 * A -ENOENT return indicates that @id was not found. 642 * A %-ENOENT return indicates that @id was not found.
640 * A -EINVAL return indicates that @id was not within valid constraints. 643 * A %-EINVAL return indicates that @id was not within valid constraints.
641 * 644 *
642 * The caller must serialize with writers. 645 * The caller must serialize with writers.
643 */ 646 */
@@ -695,10 +698,11 @@ void idr_init(struct idr *idp)
695EXPORT_SYMBOL(idr_init); 698EXPORT_SYMBOL(idr_init);
696 699
697 700
698/* 701/**
702 * DOC: IDA description
699 * IDA - IDR based ID allocator 703 * IDA - IDR based ID allocator
700 * 704 *
701 * this is id allocator without id -> pointer translation. Memory 705 * This is id allocator without id -> pointer translation. Memory
702 * usage is much lower than full blown idr because each id only 706 * usage is much lower than full blown idr because each id only
703 * occupies a bit. ida uses a custom leaf node which contains 707 * occupies a bit. ida uses a custom leaf node which contains
704 * IDA_BITMAP_BITS slots. 708 * IDA_BITMAP_BITS slots.
@@ -731,8 +735,8 @@ static void free_bitmap(struct ida *ida, struct ida_bitmap *bitmap)
731 * following function. It preallocates enough memory to satisfy the 735 * following function. It preallocates enough memory to satisfy the
732 * worst possible allocation. 736 * worst possible allocation.
733 * 737 *
734 * If the system is REALLY out of memory this function returns 0, 738 * If the system is REALLY out of memory this function returns %0,
735 * otherwise 1. 739 * otherwise %1.
736 */ 740 */
737int ida_pre_get(struct ida *ida, gfp_t gfp_mask) 741int ida_pre_get(struct ida *ida, gfp_t gfp_mask)
738{ 742{
@@ -758,17 +762,17 @@ EXPORT_SYMBOL(ida_pre_get);
758/** 762/**
759 * ida_get_new_above - allocate new ID above or equal to a start id 763 * ida_get_new_above - allocate new ID above or equal to a start id
760 * @ida: ida handle 764 * @ida: ida handle
761 * @staring_id: id to start search at 765 * @starting_id: id to start search at
762 * @p_id: pointer to the allocated handle 766 * @p_id: pointer to the allocated handle
763 * 767 *
764 * Allocate new ID above or equal to @ida. It should be called with 768 * Allocate new ID above or equal to @ida. It should be called with
765 * any required locks. 769 * any required locks.
766 * 770 *
767 * If memory is required, it will return -EAGAIN, you should unlock 771 * If memory is required, it will return %-EAGAIN, you should unlock
768 * and go back to the ida_pre_get() call. If the ida is full, it will 772 * and go back to the ida_pre_get() call. If the ida is full, it will
769 * return -ENOSPC. 773 * return %-ENOSPC.
770 * 774 *
771 * @p_id returns a value in the range @starting_id ... 0x7fffffff. 775 * @p_id returns a value in the range @starting_id ... %0x7fffffff.
772 */ 776 */
773int ida_get_new_above(struct ida *ida, int starting_id, int *p_id) 777int ida_get_new_above(struct ida *ida, int starting_id, int *p_id)
774{ 778{
@@ -850,11 +854,11 @@ EXPORT_SYMBOL(ida_get_new_above);
850 * 854 *
851 * Allocate new ID. It should be called with any required locks. 855 * Allocate new ID. It should be called with any required locks.
852 * 856 *
853 * If memory is required, it will return -EAGAIN, you should unlock 857 * If memory is required, it will return %-EAGAIN, you should unlock
854 * and go back to the idr_pre_get() call. If the idr is full, it will 858 * and go back to the idr_pre_get() call. If the idr is full, it will
855 * return -ENOSPC. 859 * return %-ENOSPC.
856 * 860 *
857 * @id returns a value in the range 0 ... 0x7fffffff. 861 * @id returns a value in the range %0 ... %0x7fffffff.
858 */ 862 */
859int ida_get_new(struct ida *ida, int *p_id) 863int ida_get_new(struct ida *ida, int *p_id)
860{ 864{
@@ -912,7 +916,7 @@ EXPORT_SYMBOL(ida_remove);
912 916
913/** 917/**
914 * ida_destroy - release all cached layers within an ida tree 918 * ida_destroy - release all cached layers within an ida tree
915 * ida: ida handle 919 * @ida: ida handle
916 */ 920 */
917void ida_destroy(struct ida *ida) 921void ida_destroy(struct ida *ida)
918{ 922{