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-rw-r--r--lib/Kconfig6
-rw-r--r--lib/Kconfig.debug6
-rw-r--r--lib/Kconfig.kmemcheck91
-rw-r--r--lib/Makefile4
-rw-r--r--lib/atomic64.c175
-rw-r--r--lib/dec_and_lock.c3
-rw-r--r--lib/gcd.c18
-rw-r--r--lib/genalloc.c1
-rw-r--r--lib/hexdump.c15
-rw-r--r--lib/kobject.c7
-rw-r--r--lib/radix-tree.c110
-rw-r--r--lib/rbtree.c34
12 files changed, 393 insertions, 77 deletions
diff --git a/lib/Kconfig b/lib/Kconfig
index 9960be04cbbe..bb1326d3839c 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -194,4 +194,10 @@ config DISABLE_OBSOLETE_CPUMASK_FUNCTIONS
194config NLATTR 194config NLATTR
195 bool 195 bool
196 196
197#
198# Generic 64-bit atomic support is selected if needed
199#
200config GENERIC_ATOMIC64
201 bool
202
197endmenu 203endmenu
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 116a35051be6..6b0c2d8a2129 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -300,7 +300,7 @@ config DEBUG_OBJECTS_ENABLE_DEFAULT
300 300
301config DEBUG_SLAB 301config DEBUG_SLAB
302 bool "Debug slab memory allocations" 302 bool "Debug slab memory allocations"
303 depends on DEBUG_KERNEL && SLAB 303 depends on DEBUG_KERNEL && SLAB && !KMEMCHECK
304 help 304 help
305 Say Y here to have the kernel do limited verification on memory 305 Say Y here to have the kernel do limited verification on memory
306 allocation as well as poisoning memory on free to catch use of freed 306 allocation as well as poisoning memory on free to catch use of freed
@@ -312,7 +312,7 @@ config DEBUG_SLAB_LEAK
312 312
313config SLUB_DEBUG_ON 313config SLUB_DEBUG_ON
314 bool "SLUB debugging on by default" 314 bool "SLUB debugging on by default"
315 depends on SLUB && SLUB_DEBUG 315 depends on SLUB && SLUB_DEBUG && !KMEMCHECK
316 default n 316 default n
317 help 317 help
318 Boot with debugging on by default. SLUB boots by default with 318 Boot with debugging on by default. SLUB boots by default with
@@ -996,3 +996,5 @@ config DMA_API_DEBUG
996source "samples/Kconfig" 996source "samples/Kconfig"
997 997
998source "lib/Kconfig.kgdb" 998source "lib/Kconfig.kgdb"
999
1000source "lib/Kconfig.kmemcheck"
diff --git a/lib/Kconfig.kmemcheck b/lib/Kconfig.kmemcheck
new file mode 100644
index 000000000000..603c81b66549
--- /dev/null
+++ b/lib/Kconfig.kmemcheck
@@ -0,0 +1,91 @@
1config HAVE_ARCH_KMEMCHECK
2 bool
3
4menuconfig KMEMCHECK
5 bool "kmemcheck: trap use of uninitialized memory"
6 depends on DEBUG_KERNEL
7 depends on !X86_USE_3DNOW
8 depends on SLUB || SLAB
9 depends on !CC_OPTIMIZE_FOR_SIZE
10 depends on !FUNCTION_TRACER
11 select FRAME_POINTER
12 select STACKTRACE
13 default n
14 help
15 This option enables tracing of dynamically allocated kernel memory
16 to see if memory is used before it has been given an initial value.
17 Be aware that this requires half of your memory for bookkeeping and
18 will insert extra code at *every* read and write to tracked memory
19 thus slow down the kernel code (but user code is unaffected).
20
21 The kernel may be started with kmemcheck=0 or kmemcheck=1 to disable
22 or enable kmemcheck at boot-time. If the kernel is started with
23 kmemcheck=0, the large memory and CPU overhead is not incurred.
24
25choice
26 prompt "kmemcheck: default mode at boot"
27 depends on KMEMCHECK
28 default KMEMCHECK_ONESHOT_BY_DEFAULT
29 help
30 This option controls the default behaviour of kmemcheck when the
31 kernel boots and no kmemcheck= parameter is given.
32
33config KMEMCHECK_DISABLED_BY_DEFAULT
34 bool "disabled"
35 depends on KMEMCHECK
36
37config KMEMCHECK_ENABLED_BY_DEFAULT
38 bool "enabled"
39 depends on KMEMCHECK
40
41config KMEMCHECK_ONESHOT_BY_DEFAULT
42 bool "one-shot"
43 depends on KMEMCHECK
44 help
45 In one-shot mode, only the first error detected is reported before
46 kmemcheck is disabled.
47
48endchoice
49
50config KMEMCHECK_QUEUE_SIZE
51 int "kmemcheck: error queue size"
52 depends on KMEMCHECK
53 default 64
54 help
55 Select the maximum number of errors to store in the queue. Since
56 errors can occur virtually anywhere and in any context, we need a
57 temporary storage area which is guarantueed not to generate any
58 other faults. The queue will be emptied as soon as a tasklet may
59 be scheduled. If the queue is full, new error reports will be
60 lost.
61
62config KMEMCHECK_SHADOW_COPY_SHIFT
63 int "kmemcheck: shadow copy size (5 => 32 bytes, 6 => 64 bytes)"
64 depends on KMEMCHECK
65 range 2 8
66 default 5
67 help
68 Select the number of shadow bytes to save along with each entry of
69 the queue. These bytes indicate what parts of an allocation are
70 initialized, uninitialized, etc. and will be displayed when an
71 error is detected to help the debugging of a particular problem.
72
73config KMEMCHECK_PARTIAL_OK
74 bool "kmemcheck: allow partially uninitialized memory"
75 depends on KMEMCHECK
76 default y
77 help
78 This option works around certain GCC optimizations that produce
79 32-bit reads from 16-bit variables where the upper 16 bits are
80 thrown away afterwards. This may of course also hide some real
81 bugs.
82
83config KMEMCHECK_BITOPS_OK
84 bool "kmemcheck: allow bit-field manipulation"
85 depends on KMEMCHECK
86 default n
87 help
88 This option silences warnings that would be generated for bit-field
89 accesses where not all the bits are initialized at the same time.
90 This may also hide some real bugs.
91
diff --git a/lib/Makefile b/lib/Makefile
index 34c5c0e6222e..b6d1857bbf08 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -21,7 +21,7 @@ lib-y += kobject.o kref.o klist.o
21 21
22obj-y += bcd.o div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \ 22obj-y += bcd.o div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \
23 bust_spinlocks.o hexdump.o kasprintf.o bitmap.o scatterlist.o \ 23 bust_spinlocks.o hexdump.o kasprintf.o bitmap.o scatterlist.o \
24 string_helpers.o 24 string_helpers.o gcd.o
25 25
26ifeq ($(CONFIG_DEBUG_KOBJECT),y) 26ifeq ($(CONFIG_DEBUG_KOBJECT),y)
27CFLAGS_kobject.o += -DDEBUG 27CFLAGS_kobject.o += -DDEBUG
@@ -95,6 +95,8 @@ obj-$(CONFIG_DMA_API_DEBUG) += dma-debug.o
95 95
96obj-$(CONFIG_GENERIC_CSUM) += checksum.o 96obj-$(CONFIG_GENERIC_CSUM) += checksum.o
97 97
98obj-$(CONFIG_GENERIC_ATOMIC64) += atomic64.o
99
98hostprogs-y := gen_crc32table 100hostprogs-y := gen_crc32table
99clean-files := crc32table.h 101clean-files := crc32table.h
100 102
diff --git a/lib/atomic64.c b/lib/atomic64.c
new file mode 100644
index 000000000000..c5e725562416
--- /dev/null
+++ b/lib/atomic64.c
@@ -0,0 +1,175 @@
1/*
2 * Generic implementation of 64-bit atomics using spinlocks,
3 * useful on processors that don't have 64-bit atomic instructions.
4 *
5 * Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version
10 * 2 of the License, or (at your option) any later version.
11 */
12#include <linux/types.h>
13#include <linux/cache.h>
14#include <linux/spinlock.h>
15#include <linux/init.h>
16#include <asm/atomic.h>
17
18/*
19 * We use a hashed array of spinlocks to provide exclusive access
20 * to each atomic64_t variable. Since this is expected to used on
21 * systems with small numbers of CPUs (<= 4 or so), we use a
22 * relatively small array of 16 spinlocks to avoid wasting too much
23 * memory on the spinlock array.
24 */
25#define NR_LOCKS 16
26
27/*
28 * Ensure each lock is in a separate cacheline.
29 */
30static union {
31 spinlock_t lock;
32 char pad[L1_CACHE_BYTES];
33} atomic64_lock[NR_LOCKS] __cacheline_aligned_in_smp;
34
35static inline spinlock_t *lock_addr(const atomic64_t *v)
36{
37 unsigned long addr = (unsigned long) v;
38
39 addr >>= L1_CACHE_SHIFT;
40 addr ^= (addr >> 8) ^ (addr >> 16);
41 return &atomic64_lock[addr & (NR_LOCKS - 1)].lock;
42}
43
44long long atomic64_read(const atomic64_t *v)
45{
46 unsigned long flags;
47 spinlock_t *lock = lock_addr(v);
48 long long val;
49
50 spin_lock_irqsave(lock, flags);
51 val = v->counter;
52 spin_unlock_irqrestore(lock, flags);
53 return val;
54}
55
56void atomic64_set(atomic64_t *v, long long i)
57{
58 unsigned long flags;
59 spinlock_t *lock = lock_addr(v);
60
61 spin_lock_irqsave(lock, flags);
62 v->counter = i;
63 spin_unlock_irqrestore(lock, flags);
64}
65
66void atomic64_add(long long a, atomic64_t *v)
67{
68 unsigned long flags;
69 spinlock_t *lock = lock_addr(v);
70
71 spin_lock_irqsave(lock, flags);
72 v->counter += a;
73 spin_unlock_irqrestore(lock, flags);
74}
75
76long long atomic64_add_return(long long a, atomic64_t *v)
77{
78 unsigned long flags;
79 spinlock_t *lock = lock_addr(v);
80 long long val;
81
82 spin_lock_irqsave(lock, flags);
83 val = v->counter += a;
84 spin_unlock_irqrestore(lock, flags);
85 return val;
86}
87
88void atomic64_sub(long long a, atomic64_t *v)
89{
90 unsigned long flags;
91 spinlock_t *lock = lock_addr(v);
92
93 spin_lock_irqsave(lock, flags);
94 v->counter -= a;
95 spin_unlock_irqrestore(lock, flags);
96}
97
98long long atomic64_sub_return(long long a, atomic64_t *v)
99{
100 unsigned long flags;
101 spinlock_t *lock = lock_addr(v);
102 long long val;
103
104 spin_lock_irqsave(lock, flags);
105 val = v->counter -= a;
106 spin_unlock_irqrestore(lock, flags);
107 return val;
108}
109
110long long atomic64_dec_if_positive(atomic64_t *v)
111{
112 unsigned long flags;
113 spinlock_t *lock = lock_addr(v);
114 long long val;
115
116 spin_lock_irqsave(lock, flags);
117 val = v->counter - 1;
118 if (val >= 0)
119 v->counter = val;
120 spin_unlock_irqrestore(lock, flags);
121 return val;
122}
123
124long long atomic64_cmpxchg(atomic64_t *v, long long o, long long n)
125{
126 unsigned long flags;
127 spinlock_t *lock = lock_addr(v);
128 long long val;
129
130 spin_lock_irqsave(lock, flags);
131 val = v->counter;
132 if (val == o)
133 v->counter = n;
134 spin_unlock_irqrestore(lock, flags);
135 return val;
136}
137
138long long atomic64_xchg(atomic64_t *v, long long new)
139{
140 unsigned long flags;
141 spinlock_t *lock = lock_addr(v);
142 long long val;
143
144 spin_lock_irqsave(lock, flags);
145 val = v->counter;
146 v->counter = new;
147 spin_unlock_irqrestore(lock, flags);
148 return val;
149}
150
151int atomic64_add_unless(atomic64_t *v, long long a, long long u)
152{
153 unsigned long flags;
154 spinlock_t *lock = lock_addr(v);
155 int ret = 1;
156
157 spin_lock_irqsave(lock, flags);
158 if (v->counter != u) {
159 v->counter += a;
160 ret = 0;
161 }
162 spin_unlock_irqrestore(lock, flags);
163 return ret;
164}
165
166static int init_atomic64_lock(void)
167{
168 int i;
169
170 for (i = 0; i < NR_LOCKS; ++i)
171 spin_lock_init(&atomic64_lock[i].lock);
172 return 0;
173}
174
175pure_initcall(init_atomic64_lock);
diff --git a/lib/dec_and_lock.c b/lib/dec_and_lock.c
index a65c31455541..e73822aa6e9a 100644
--- a/lib/dec_and_lock.c
+++ b/lib/dec_and_lock.c
@@ -19,11 +19,10 @@
19 */ 19 */
20int _atomic_dec_and_lock(atomic_t *atomic, spinlock_t *lock) 20int _atomic_dec_and_lock(atomic_t *atomic, spinlock_t *lock)
21{ 21{
22#ifdef CONFIG_SMP
23 /* Subtract 1 from counter unless that drops it to 0 (ie. it was 1) */ 22 /* Subtract 1 from counter unless that drops it to 0 (ie. it was 1) */
24 if (atomic_add_unless(atomic, -1, 1)) 23 if (atomic_add_unless(atomic, -1, 1))
25 return 0; 24 return 0;
26#endif 25
27 /* Otherwise do it the slow way */ 26 /* Otherwise do it the slow way */
28 spin_lock(lock); 27 spin_lock(lock);
29 if (atomic_dec_and_test(atomic)) 28 if (atomic_dec_and_test(atomic))
diff --git a/lib/gcd.c b/lib/gcd.c
new file mode 100644
index 000000000000..f879033d9822
--- /dev/null
+++ b/lib/gcd.c
@@ -0,0 +1,18 @@
1#include <linux/kernel.h>
2#include <linux/gcd.h>
3#include <linux/module.h>
4
5/* Greatest common divisor */
6unsigned long gcd(unsigned long a, unsigned long b)
7{
8 unsigned long r;
9
10 if (a < b)
11 swap(a, b);
12 while ((r = a % b) != 0) {
13 a = b;
14 b = r;
15 }
16 return b;
17}
18EXPORT_SYMBOL_GPL(gcd);
diff --git a/lib/genalloc.c b/lib/genalloc.c
index f6d276db2d58..eed2bdb865e7 100644
--- a/lib/genalloc.c
+++ b/lib/genalloc.c
@@ -85,7 +85,6 @@ void gen_pool_destroy(struct gen_pool *pool)
85 int bit, end_bit; 85 int bit, end_bit;
86 86
87 87
88 write_lock(&pool->lock);
89 list_for_each_safe(_chunk, _next_chunk, &pool->chunks) { 88 list_for_each_safe(_chunk, _next_chunk, &pool->chunks) {
90 chunk = list_entry(_chunk, struct gen_pool_chunk, next_chunk); 89 chunk = list_entry(_chunk, struct gen_pool_chunk, next_chunk);
91 list_del(&chunk->next_chunk); 90 list_del(&chunk->next_chunk);
diff --git a/lib/hexdump.c b/lib/hexdump.c
index f07c0db81d26..39af2560f765 100644
--- a/lib/hexdump.c
+++ b/lib/hexdump.c
@@ -65,7 +65,8 @@ void hex_dump_to_buffer(const void *buf, size_t len, int rowsize,
65 65
66 for (j = 0; j < ngroups; j++) 66 for (j = 0; j < ngroups; j++)
67 lx += scnprintf(linebuf + lx, linebuflen - lx, 67 lx += scnprintf(linebuf + lx, linebuflen - lx,
68 "%16.16llx ", (unsigned long long)*(ptr8 + j)); 68 "%s%16.16llx", j ? " " : "",
69 (unsigned long long)*(ptr8 + j));
69 ascii_column = 17 * ngroups + 2; 70 ascii_column = 17 * ngroups + 2;
70 break; 71 break;
71 } 72 }
@@ -76,7 +77,7 @@ void hex_dump_to_buffer(const void *buf, size_t len, int rowsize,
76 77
77 for (j = 0; j < ngroups; j++) 78 for (j = 0; j < ngroups; j++)
78 lx += scnprintf(linebuf + lx, linebuflen - lx, 79 lx += scnprintf(linebuf + lx, linebuflen - lx,
79 "%8.8x ", *(ptr4 + j)); 80 "%s%8.8x", j ? " " : "", *(ptr4 + j));
80 ascii_column = 9 * ngroups + 2; 81 ascii_column = 9 * ngroups + 2;
81 break; 82 break;
82 } 83 }
@@ -87,19 +88,21 @@ void hex_dump_to_buffer(const void *buf, size_t len, int rowsize,
87 88
88 for (j = 0; j < ngroups; j++) 89 for (j = 0; j < ngroups; j++)
89 lx += scnprintf(linebuf + lx, linebuflen - lx, 90 lx += scnprintf(linebuf + lx, linebuflen - lx,
90 "%4.4x ", *(ptr2 + j)); 91 "%s%4.4x", j ? " " : "", *(ptr2 + j));
91 ascii_column = 5 * ngroups + 2; 92 ascii_column = 5 * ngroups + 2;
92 break; 93 break;
93 } 94 }
94 95
95 default: 96 default:
96 for (j = 0; (j < rowsize) && (j < len) && (lx + 4) < linebuflen; 97 for (j = 0; (j < len) && (lx + 3) <= linebuflen; j++) {
97 j++) {
98 ch = ptr[j]; 98 ch = ptr[j];
99 linebuf[lx++] = hex_asc_hi(ch); 99 linebuf[lx++] = hex_asc_hi(ch);
100 linebuf[lx++] = hex_asc_lo(ch); 100 linebuf[lx++] = hex_asc_lo(ch);
101 linebuf[lx++] = ' '; 101 linebuf[lx++] = ' ';
102 } 102 }
103 if (j)
104 lx--;
105
103 ascii_column = 3 * rowsize + 2; 106 ascii_column = 3 * rowsize + 2;
104 break; 107 break;
105 } 108 }
@@ -108,7 +111,7 @@ void hex_dump_to_buffer(const void *buf, size_t len, int rowsize,
108 111
109 while (lx < (linebuflen - 1) && lx < (ascii_column - 1)) 112 while (lx < (linebuflen - 1) && lx < (ascii_column - 1))
110 linebuf[lx++] = ' '; 113 linebuf[lx++] = ' ';
111 for (j = 0; (j < rowsize) && (j < len) && (lx + 2) < linebuflen; j++) 114 for (j = 0; (j < len) && (lx + 2) < linebuflen; j++)
112 linebuf[lx++] = (isascii(ptr[j]) && isprint(ptr[j])) ? ptr[j] 115 linebuf[lx++] = (isascii(ptr[j]) && isprint(ptr[j])) ? ptr[j]
113 : '.'; 116 : '.';
114nil: 117nil:
diff --git a/lib/kobject.c b/lib/kobject.c
index bacf6fe4f7a0..b512b746d2af 100644
--- a/lib/kobject.c
+++ b/lib/kobject.c
@@ -793,11 +793,16 @@ static struct kset *kset_create(const char *name,
793 struct kobject *parent_kobj) 793 struct kobject *parent_kobj)
794{ 794{
795 struct kset *kset; 795 struct kset *kset;
796 int retval;
796 797
797 kset = kzalloc(sizeof(*kset), GFP_KERNEL); 798 kset = kzalloc(sizeof(*kset), GFP_KERNEL);
798 if (!kset) 799 if (!kset)
799 return NULL; 800 return NULL;
800 kobject_set_name(&kset->kobj, name); 801 retval = kobject_set_name(&kset->kobj, name);
802 if (retval) {
803 kfree(kset);
804 return NULL;
805 }
801 kset->uevent_ops = uevent_ops; 806 kset->uevent_ops = uevent_ops;
802 kset->kobj.parent = parent_kobj; 807 kset->kobj.parent = parent_kobj;
803 808
diff --git a/lib/radix-tree.c b/lib/radix-tree.c
index 4bb42a0344ec..23abbd93cae1 100644
--- a/lib/radix-tree.c
+++ b/lib/radix-tree.c
@@ -351,20 +351,12 @@ int radix_tree_insert(struct radix_tree_root *root,
351} 351}
352EXPORT_SYMBOL(radix_tree_insert); 352EXPORT_SYMBOL(radix_tree_insert);
353 353
354/** 354/*
355 * radix_tree_lookup_slot - lookup a slot in a radix tree 355 * is_slot == 1 : search for the slot.
356 * @root: radix tree root 356 * is_slot == 0 : search for the node.
357 * @index: index key
358 *
359 * Returns: the slot corresponding to the position @index in the
360 * radix tree @root. This is useful for update-if-exists operations.
361 *
362 * This function can be called under rcu_read_lock iff the slot is not
363 * modified by radix_tree_replace_slot, otherwise it must be called
364 * exclusive from other writers. Any dereference of the slot must be done
365 * using radix_tree_deref_slot.
366 */ 357 */
367void **radix_tree_lookup_slot(struct radix_tree_root *root, unsigned long index) 358static void *radix_tree_lookup_element(struct radix_tree_root *root,
359 unsigned long index, int is_slot)
368{ 360{
369 unsigned int height, shift; 361 unsigned int height, shift;
370 struct radix_tree_node *node, **slot; 362 struct radix_tree_node *node, **slot;
@@ -376,7 +368,7 @@ void **radix_tree_lookup_slot(struct radix_tree_root *root, unsigned long index)
376 if (!radix_tree_is_indirect_ptr(node)) { 368 if (!radix_tree_is_indirect_ptr(node)) {
377 if (index > 0) 369 if (index > 0)
378 return NULL; 370 return NULL;
379 return (void **)&root->rnode; 371 return is_slot ? (void *)&root->rnode : node;
380 } 372 }
381 node = radix_tree_indirect_to_ptr(node); 373 node = radix_tree_indirect_to_ptr(node);
382 374
@@ -397,7 +389,25 @@ void **radix_tree_lookup_slot(struct radix_tree_root *root, unsigned long index)
397 height--; 389 height--;
398 } while (height > 0); 390 } while (height > 0);
399 391
400 return (void **)slot; 392 return is_slot ? (void *)slot:node;
393}
394
395/**
396 * radix_tree_lookup_slot - lookup a slot in a radix tree
397 * @root: radix tree root
398 * @index: index key
399 *
400 * Returns: the slot corresponding to the position @index in the
401 * radix tree @root. This is useful for update-if-exists operations.
402 *
403 * This function can be called under rcu_read_lock iff the slot is not
404 * modified by radix_tree_replace_slot, otherwise it must be called
405 * exclusive from other writers. Any dereference of the slot must be done
406 * using radix_tree_deref_slot.
407 */
408void **radix_tree_lookup_slot(struct radix_tree_root *root, unsigned long index)
409{
410 return (void **)radix_tree_lookup_element(root, index, 1);
401} 411}
402EXPORT_SYMBOL(radix_tree_lookup_slot); 412EXPORT_SYMBOL(radix_tree_lookup_slot);
403 413
@@ -415,38 +425,7 @@ EXPORT_SYMBOL(radix_tree_lookup_slot);
415 */ 425 */
416void *radix_tree_lookup(struct radix_tree_root *root, unsigned long index) 426void *radix_tree_lookup(struct radix_tree_root *root, unsigned long index)
417{ 427{
418 unsigned int height, shift; 428 return radix_tree_lookup_element(root, index, 0);
419 struct radix_tree_node *node, **slot;
420
421 node = rcu_dereference(root->rnode);
422 if (node == NULL)
423 return NULL;
424
425 if (!radix_tree_is_indirect_ptr(node)) {
426 if (index > 0)
427 return NULL;
428 return node;
429 }
430 node = radix_tree_indirect_to_ptr(node);
431
432 height = node->height;
433 if (index > radix_tree_maxindex(height))
434 return NULL;
435
436 shift = (height-1) * RADIX_TREE_MAP_SHIFT;
437
438 do {
439 slot = (struct radix_tree_node **)
440 (node->slots + ((index>>shift) & RADIX_TREE_MAP_MASK));
441 node = rcu_dereference(*slot);
442 if (node == NULL)
443 return NULL;
444
445 shift -= RADIX_TREE_MAP_SHIFT;
446 height--;
447 } while (height > 0);
448
449 return node;
450} 429}
451EXPORT_SYMBOL(radix_tree_lookup); 430EXPORT_SYMBOL(radix_tree_lookup);
452 431
@@ -666,6 +645,43 @@ unsigned long radix_tree_next_hole(struct radix_tree_root *root,
666} 645}
667EXPORT_SYMBOL(radix_tree_next_hole); 646EXPORT_SYMBOL(radix_tree_next_hole);
668 647
648/**
649 * radix_tree_prev_hole - find the prev hole (not-present entry)
650 * @root: tree root
651 * @index: index key
652 * @max_scan: maximum range to search
653 *
654 * Search backwards in the range [max(index-max_scan+1, 0), index]
655 * for the first hole.
656 *
657 * Returns: the index of the hole if found, otherwise returns an index
658 * outside of the set specified (in which case 'index - return >= max_scan'
659 * will be true). In rare cases of wrap-around, LONG_MAX will be returned.
660 *
661 * radix_tree_next_hole may be called under rcu_read_lock. However, like
662 * radix_tree_gang_lookup, this will not atomically search a snapshot of
663 * the tree at a single point in time. For example, if a hole is created
664 * at index 10, then subsequently a hole is created at index 5,
665 * radix_tree_prev_hole covering both indexes may return 5 if called under
666 * rcu_read_lock.
667 */
668unsigned long radix_tree_prev_hole(struct radix_tree_root *root,
669 unsigned long index, unsigned long max_scan)
670{
671 unsigned long i;
672
673 for (i = 0; i < max_scan; i++) {
674 if (!radix_tree_lookup(root, index))
675 break;
676 index--;
677 if (index == LONG_MAX)
678 break;
679 }
680
681 return index;
682}
683EXPORT_SYMBOL(radix_tree_prev_hole);
684
669static unsigned int 685static unsigned int
670__lookup(struct radix_tree_node *slot, void ***results, unsigned long index, 686__lookup(struct radix_tree_node *slot, void ***results, unsigned long index,
671 unsigned int max_items, unsigned long *next_index) 687 unsigned int max_items, unsigned long *next_index)
diff --git a/lib/rbtree.c b/lib/rbtree.c
index f653659e0bc1..e2aa3be29858 100644
--- a/lib/rbtree.c
+++ b/lib/rbtree.c
@@ -231,34 +231,34 @@ void rb_erase(struct rb_node *node, struct rb_root *root)
231 node = node->rb_right; 231 node = node->rb_right;
232 while ((left = node->rb_left) != NULL) 232 while ((left = node->rb_left) != NULL)
233 node = left; 233 node = left;
234
235 if (rb_parent(old)) {
236 if (rb_parent(old)->rb_left == old)
237 rb_parent(old)->rb_left = node;
238 else
239 rb_parent(old)->rb_right = node;
240 } else
241 root->rb_node = node;
242
234 child = node->rb_right; 243 child = node->rb_right;
235 parent = rb_parent(node); 244 parent = rb_parent(node);
236 color = rb_color(node); 245 color = rb_color(node);
237 246
238 if (child)
239 rb_set_parent(child, parent);
240 if (parent == old) { 247 if (parent == old) {
241 parent->rb_right = child;
242 parent = node; 248 parent = node;
243 } else 249 } else {
250 if (child)
251 rb_set_parent(child, parent);
244 parent->rb_left = child; 252 parent->rb_left = child;
245 253
254 node->rb_right = old->rb_right;
255 rb_set_parent(old->rb_right, node);
256 }
257
246 node->rb_parent_color = old->rb_parent_color; 258 node->rb_parent_color = old->rb_parent_color;
247 node->rb_right = old->rb_right;
248 node->rb_left = old->rb_left; 259 node->rb_left = old->rb_left;
249
250 if (rb_parent(old))
251 {
252 if (rb_parent(old)->rb_left == old)
253 rb_parent(old)->rb_left = node;
254 else
255 rb_parent(old)->rb_right = node;
256 } else
257 root->rb_node = node;
258
259 rb_set_parent(old->rb_left, node); 260 rb_set_parent(old->rb_left, node);
260 if (old->rb_right) 261
261 rb_set_parent(old->rb_right, node);
262 goto color; 262 goto color;
263 } 263 }
264 264