From 0679cc483669d08153d158273455398a389ee9ca Mon Sep 17 00:00:00 2001 From: Rasmus Villemoes Date: Wed, 6 Aug 2014 16:09:49 -0700 Subject: lib: bitmap: make nbits parameter of bitmap_empty unsigned Many functions in lib/bitmap.c start with an expression such as lim = bits/BITS_PER_LONG. Since bits has type (signed) int, and since gcc cannot know that it is in fact non-negative, it generates worse code than it could. These patches, mostly consisting of changing various parameters to unsigned, gives a slight overall code reduction: add/remove: 1/1 grow/shrink: 8/16 up/down: 251/-414 (-163) function old new delta tick_device_uses_broadcast 335 425 +90 __irq_alloc_descs 498 554 +56 __bitmap_andnot 73 115 +42 __bitmap_and 70 101 +31 bitmap_weight - 11 +11 copy_hugetlb_page_range 752 762 +10 follow_hugetlb_page 846 854 +8 hugetlb_init 1415 1417 +2 hugetlb_nrpages_setup 130 131 +1 hugetlb_add_hstate 377 376 -1 bitmap_allocate_region 82 80 -2 select_task_rq_fair 2202 2191 -11 hweight_long 66 55 -11 __reg_op 230 219 -11 dm_stats_message 2849 2833 -16 bitmap_parselist 92 74 -18 __bitmap_weight 115 97 -18 __bitmap_subset 153 129 -24 __bitmap_full 128 104 -24 __bitmap_empty 120 96 -24 bitmap_set 179 149 -30 bitmap_clear 185 155 -30 __bitmap_equal 136 105 -31 __bitmap_intersects 148 108 -40 __bitmap_complement 109 67 -42 tick_device_setup_broadcast_func.isra 81 - -81 [The increases in __bitmap_and{,not} are due to bug fixes 17/18,18/18. No idea why bitmap_weight suddenly appears.] While 163 bytes treewide is insignificant, I believe the bitmap functions are often called with locks held, so saving even a few cycles might be worth it. While making these changes, I found a few other things that might be worth including. 16,17,18 are actual bug fixes. The rest shouldn't change the behaviour of any of the functions, provided no-one passed negative nbits values. If something should come up, it should be fairly bisectable. A few issues I thought about, but didn't know what to do with: * Many of the functions misbehave if nbits is compile-time 0; the out-of-line functions generally handle 0 correctly. bitmap_fill() is particularly bad, whether the 0 is known at compile time or not. It would probably be nice to add detection of at least compile-time 0 and handle that appropriately. * I didn't change __bitmap_shift_{left,right} to use unsigned because I want to fully understand why the algorithm works before making that change. However, AFAICT, they behave correctly for all (positive) shift amounts. This is not the case for the small_const_nbits versions. If for example nbits = n = BITS_PER_LONG, the shift operators turn into no-ops (at least on x86), so one get *dst = *src, whereas one would expect to get *dst=0. That difference in behaviour is somewhat annoying. This patch (of 18): The compiler can generate slightly smaller and simpler code when it knows that "nbits" is non-negative. Since no-one passes a negative bit-count, this shouldn't affect the semantics. Signed-off-by: Rasmus Villemoes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/bitmap.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include/linux/bitmap.h') diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h index 7ad634501e48..3d3fd6b2f157 100644 --- a/include/linux/bitmap.h +++ b/include/linux/bitmap.h @@ -88,7 +88,7 @@ * lib/bitmap.c provides these functions: */ -extern int __bitmap_empty(const unsigned long *bitmap, int bits); +extern int __bitmap_empty(const unsigned long *bitmap, unsigned int nbits); extern int __bitmap_full(const unsigned long *bitmap, int bits); extern int __bitmap_equal(const unsigned long *bitmap1, const unsigned long *bitmap2, int bits); @@ -257,7 +257,7 @@ static inline int bitmap_subset(const unsigned long *src1, return __bitmap_subset(src1, src2, nbits); } -static inline int bitmap_empty(const unsigned long *src, int nbits) +static inline int bitmap_empty(const unsigned long *src, unsigned nbits) { if (small_const_nbits(nbits)) return ! (*src & BITMAP_LAST_WORD_MASK(nbits)); -- cgit v1.2.3 From 8397927c8045c58afc68ef839855eb5505259df3 Mon Sep 17 00:00:00 2001 From: Rasmus Villemoes Date: Wed, 6 Aug 2014 16:09:51 -0700 Subject: lib: bitmap: make nbits parameter of bitmap_full unsigned The compiler can generate slightly smaller and simpler code when it knows that "nbits" is non-negative. Since no-one passes a negative bit-count, this shouldn't affect the semantics. Signed-off-by: Rasmus Villemoes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/bitmap.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include/linux/bitmap.h') diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h index 3d3fd6b2f157..bc7e520d3f78 100644 --- a/include/linux/bitmap.h +++ b/include/linux/bitmap.h @@ -89,7 +89,7 @@ */ extern int __bitmap_empty(const unsigned long *bitmap, unsigned int nbits); -extern int __bitmap_full(const unsigned long *bitmap, int bits); +extern int __bitmap_full(const unsigned long *bitmap, unsigned int nbits); extern int __bitmap_equal(const unsigned long *bitmap1, const unsigned long *bitmap2, int bits); extern void __bitmap_complement(unsigned long *dst, const unsigned long *src, @@ -265,7 +265,7 @@ static inline int bitmap_empty(const unsigned long *src, unsigned nbits) return __bitmap_empty(src, nbits); } -static inline int bitmap_full(const unsigned long *src, int nbits) +static inline int bitmap_full(const unsigned long *src, unsigned int nbits) { if (small_const_nbits(nbits)) return ! (~(*src) & BITMAP_LAST_WORD_MASK(nbits)); -- cgit v1.2.3 From 5e068069319a9fb02fb14337c2cedeae5f16d812 Mon Sep 17 00:00:00 2001 From: Rasmus Villemoes Date: Wed, 6 Aug 2014 16:09:53 -0700 Subject: lib: bitmap: make nbits parameter of bitmap_equal unsigned The compiler can generate slightly smaller and simpler code when it knows that "nbits" is non-negative. Since no-one passes a negative bit-count, this shouldn't affect the semantics. Signed-off-by: Rasmus Villemoes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/bitmap.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/bitmap.h') diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h index bc7e520d3f78..1e0f46c91125 100644 --- a/include/linux/bitmap.h +++ b/include/linux/bitmap.h @@ -91,7 +91,7 @@ extern int __bitmap_empty(const unsigned long *bitmap, unsigned int nbits); extern int __bitmap_full(const unsigned long *bitmap, unsigned int nbits); extern int __bitmap_equal(const unsigned long *bitmap1, - const unsigned long *bitmap2, int bits); + const unsigned long *bitmap2, unsigned int nbits); extern void __bitmap_complement(unsigned long *dst, const unsigned long *src, int bits); extern void __bitmap_shift_right(unsigned long *dst, -- cgit v1.2.3 From 3d6684f4e6a46f3a8263f5681e093bccbb767a1c Mon Sep 17 00:00:00 2001 From: Rasmus Villemoes Date: Wed, 6 Aug 2014 16:09:55 -0700 Subject: lib: bitmap: make nbits parameter of bitmap_complement unsigned The compiler can generate slightly smaller and simpler code when it knows that "nbits" is non-negative. Since no-one passes a negative bit-count, this shouldn't affect the semantics. Signed-off-by: Rasmus Villemoes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/bitmap.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'include/linux/bitmap.h') diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h index 1e0f46c91125..21fb52ffe444 100644 --- a/include/linux/bitmap.h +++ b/include/linux/bitmap.h @@ -93,7 +93,7 @@ extern int __bitmap_full(const unsigned long *bitmap, unsigned int nbits); extern int __bitmap_equal(const unsigned long *bitmap1, const unsigned long *bitmap2, unsigned int nbits); extern void __bitmap_complement(unsigned long *dst, const unsigned long *src, - int bits); + unsigned int nbits); extern void __bitmap_shift_right(unsigned long *dst, const unsigned long *src, int shift, int bits); extern void __bitmap_shift_left(unsigned long *dst, @@ -222,7 +222,7 @@ static inline int bitmap_andnot(unsigned long *dst, const unsigned long *src1, } static inline void bitmap_complement(unsigned long *dst, const unsigned long *src, - int nbits) + unsigned int nbits) { if (small_const_nbits(nbits)) *dst = ~(*src) & BITMAP_LAST_WORD_MASK(nbits); @@ -231,7 +231,7 @@ static inline void bitmap_complement(unsigned long *dst, const unsigned long *sr } static inline int bitmap_equal(const unsigned long *src1, - const unsigned long *src2, int nbits) + const unsigned long *src2, unsigned int nbits) { if (small_const_nbits(nbits)) return ! ((*src1 ^ *src2) & BITMAP_LAST_WORD_MASK(nbits)); -- cgit v1.2.3 From 65b4ee62c9cd10640f0054f47fd84c7920e8c118 Mon Sep 17 00:00:00 2001 From: Rasmus Villemoes Date: Wed, 6 Aug 2014 16:09:57 -0700 Subject: lib: bitmap: remove unnecessary mask from bitmap_complement Since the extra bits are "don't care", there is no reason to mask the last word to the used bits when complementing. This shaves off yet a few bytes. Signed-off-by: Rasmus Villemoes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/bitmap.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/bitmap.h') diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h index 21fb52ffe444..f42d72d5fe82 100644 --- a/include/linux/bitmap.h +++ b/include/linux/bitmap.h @@ -225,7 +225,7 @@ static inline void bitmap_complement(unsigned long *dst, const unsigned long *sr unsigned int nbits) { if (small_const_nbits(nbits)) - *dst = ~(*src) & BITMAP_LAST_WORD_MASK(nbits); + *dst = ~(*src); else __bitmap_complement(dst, src, nbits); } -- cgit v1.2.3 From 2f9305eb31097fdd3dc86daca65d8097d1fcf2ff Mon Sep 17 00:00:00 2001 From: Rasmus Villemoes Date: Wed, 6 Aug 2014 16:09:59 -0700 Subject: lib: bitmap: make nbits parameter of bitmap_{and,or,xor,andnot} unsigned This change is only for consistency with the changes to the other bitmap_* functions; it doesn't change the size of the generated code: inside BITS_TO_LONGS there is a sizeof(long), which causes bits to be interpreted as unsigned anyway. Signed-off-by: Rasmus Villemoes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/bitmap.h | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) (limited to 'include/linux/bitmap.h') diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h index f42d72d5fe82..7048782fe5b9 100644 --- a/include/linux/bitmap.h +++ b/include/linux/bitmap.h @@ -99,13 +99,13 @@ extern void __bitmap_shift_right(unsigned long *dst, extern void __bitmap_shift_left(unsigned long *dst, const unsigned long *src, int shift, int bits); extern int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1, - const unsigned long *bitmap2, int bits); + const unsigned long *bitmap2, unsigned int nbits); extern void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1, - const unsigned long *bitmap2, int bits); + const unsigned long *bitmap2, unsigned int nbits); extern void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1, - const unsigned long *bitmap2, int bits); + const unsigned long *bitmap2, unsigned int nbits); extern int __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1, - const unsigned long *bitmap2, int bits); + const unsigned long *bitmap2, unsigned int nbits); extern int __bitmap_intersects(const unsigned long *bitmap1, const unsigned long *bitmap2, int bits); extern int __bitmap_subset(const unsigned long *bitmap1, @@ -188,7 +188,7 @@ static inline void bitmap_copy(unsigned long *dst, const unsigned long *src, } static inline int bitmap_and(unsigned long *dst, const unsigned long *src1, - const unsigned long *src2, int nbits) + const unsigned long *src2, unsigned int nbits) { if (small_const_nbits(nbits)) return (*dst = *src1 & *src2) != 0; @@ -196,7 +196,7 @@ static inline int bitmap_and(unsigned long *dst, const unsigned long *src1, } static inline void bitmap_or(unsigned long *dst, const unsigned long *src1, - const unsigned long *src2, int nbits) + const unsigned long *src2, unsigned int nbits) { if (small_const_nbits(nbits)) *dst = *src1 | *src2; @@ -205,7 +205,7 @@ static inline void bitmap_or(unsigned long *dst, const unsigned long *src1, } static inline void bitmap_xor(unsigned long *dst, const unsigned long *src1, - const unsigned long *src2, int nbits) + const unsigned long *src2, unsigned int nbits) { if (small_const_nbits(nbits)) *dst = *src1 ^ *src2; @@ -214,7 +214,7 @@ static inline void bitmap_xor(unsigned long *dst, const unsigned long *src1, } static inline int bitmap_andnot(unsigned long *dst, const unsigned long *src1, - const unsigned long *src2, int nbits) + const unsigned long *src2, unsigned int nbits) { if (small_const_nbits(nbits)) return (*dst = *src1 & ~(*src2)) != 0; -- cgit v1.2.3 From 6dfe9799c2a03d225316a3e959b0447f3f50303e Mon Sep 17 00:00:00 2001 From: Rasmus Villemoes Date: Wed, 6 Aug 2014 16:10:01 -0700 Subject: lib: bitmap: make nbits parameter of bitmap_intersects unsigned The compiler can generate slightly smaller and simpler code when it knows that "nbits" is non-negative. Since no-one passes a negative bit-count, this shouldn't affect the semantics. Signed-off-by: Rasmus Villemoes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/bitmap.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include/linux/bitmap.h') diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h index 7048782fe5b9..2f3f3a4d5996 100644 --- a/include/linux/bitmap.h +++ b/include/linux/bitmap.h @@ -107,7 +107,7 @@ extern void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1, extern int __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1, const unsigned long *bitmap2, unsigned int nbits); extern int __bitmap_intersects(const unsigned long *bitmap1, - const unsigned long *bitmap2, int bits); + const unsigned long *bitmap2, unsigned int nbits); extern int __bitmap_subset(const unsigned long *bitmap1, const unsigned long *bitmap2, int bits); extern int __bitmap_weight(const unsigned long *bitmap, int bits); @@ -240,7 +240,7 @@ static inline int bitmap_equal(const unsigned long *src1, } static inline int bitmap_intersects(const unsigned long *src1, - const unsigned long *src2, int nbits) + const unsigned long *src2, unsigned int nbits) { if (small_const_nbits(nbits)) return ((*src1 & *src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0; -- cgit v1.2.3 From 5be20213e855550de2b32fde6fc116f74bab86a6 Mon Sep 17 00:00:00 2001 From: Rasmus Villemoes Date: Wed, 6 Aug 2014 16:10:03 -0700 Subject: lib: bitmap: make nbits parameter of bitmap_subset unsigned The compiler can generate slightly smaller and simpler code when it knows that "nbits" is non-negative. Since no-one passes a negative bit-count, this shouldn't affect the semantics. Signed-off-by: Rasmus Villemoes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/bitmap.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include/linux/bitmap.h') diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h index 2f3f3a4d5996..87e88f79def1 100644 --- a/include/linux/bitmap.h +++ b/include/linux/bitmap.h @@ -109,7 +109,7 @@ extern int __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1, extern int __bitmap_intersects(const unsigned long *bitmap1, const unsigned long *bitmap2, unsigned int nbits); extern int __bitmap_subset(const unsigned long *bitmap1, - const unsigned long *bitmap2, int bits); + const unsigned long *bitmap2, unsigned int nbits); extern int __bitmap_weight(const unsigned long *bitmap, int bits); extern void bitmap_set(unsigned long *map, int i, int len); @@ -249,7 +249,7 @@ static inline int bitmap_intersects(const unsigned long *src1, } static inline int bitmap_subset(const unsigned long *src1, - const unsigned long *src2, int nbits) + const unsigned long *src2, unsigned int nbits) { if (small_const_nbits(nbits)) return ! ((*src1 & ~(*src2)) & BITMAP_LAST_WORD_MASK(nbits)); -- cgit v1.2.3 From 877d9f3b63ac2e5dbc51cbcdff156433f03b3a32 Mon Sep 17 00:00:00 2001 From: Rasmus Villemoes Date: Wed, 6 Aug 2014 16:10:05 -0700 Subject: lib: bitmap: make nbits parameter of bitmap_weight unsigned The compiler can generate slightly smaller and simpler code when it knows that "nbits" is non-negative. Since no-one passes a negative bit-count, this shouldn't affect the semantics. I didn't change the return type, since that might change the semantics of some expression containing a call to bitmap_weight(). Certainly an int is capable of holding the result. Signed-off-by: Rasmus Villemoes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/bitmap.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include/linux/bitmap.h') diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h index 87e88f79def1..64b0ebe9f9a8 100644 --- a/include/linux/bitmap.h +++ b/include/linux/bitmap.h @@ -110,7 +110,7 @@ extern int __bitmap_intersects(const unsigned long *bitmap1, const unsigned long *bitmap2, unsigned int nbits); extern int __bitmap_subset(const unsigned long *bitmap1, const unsigned long *bitmap2, unsigned int nbits); -extern int __bitmap_weight(const unsigned long *bitmap, int bits); +extern int __bitmap_weight(const unsigned long *bitmap, unsigned int nbits); extern void bitmap_set(unsigned long *map, int i, int len); extern void bitmap_clear(unsigned long *map, int start, int nr); @@ -273,7 +273,7 @@ static inline int bitmap_full(const unsigned long *src, unsigned int nbits) return __bitmap_full(src, nbits); } -static inline int bitmap_weight(const unsigned long *src, int nbits) +static inline int bitmap_weight(const unsigned long *src, unsigned int nbits) { if (small_const_nbits(nbits)) return hweight_long(*src & BITMAP_LAST_WORD_MASK(nbits)); -- cgit v1.2.3 From fb5ac54263ef3fcb5c469a61e0ab6b06e45e2307 Mon Sep 17 00:00:00 2001 From: Rasmus Villemoes Date: Wed, 6 Aug 2014 16:10:07 -0700 Subject: lib: bitmap: make the start index of bitmap_set unsigned The compiler can generate slightly smaller and simpler code when it knows that "start" is non-negative. Also, use the names "start" and "len" for the two parameters in both header file and implementation, instead of the previous mix. Signed-off-by: Rasmus Villemoes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/bitmap.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/bitmap.h') diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h index 64b0ebe9f9a8..ad2c67d3583e 100644 --- a/include/linux/bitmap.h +++ b/include/linux/bitmap.h @@ -112,7 +112,7 @@ extern int __bitmap_subset(const unsigned long *bitmap1, const unsigned long *bitmap2, unsigned int nbits); extern int __bitmap_weight(const unsigned long *bitmap, unsigned int nbits); -extern void bitmap_set(unsigned long *map, int i, int len); +extern void bitmap_set(unsigned long *map, unsigned int start, int len); extern void bitmap_clear(unsigned long *map, int start, int nr); extern unsigned long bitmap_find_next_zero_area(unsigned long *map, unsigned long size, -- cgit v1.2.3 From 154f5e38f30f262025c8c2e825376f6eb51e8bcb Mon Sep 17 00:00:00 2001 From: Rasmus Villemoes Date: Wed, 6 Aug 2014 16:10:10 -0700 Subject: lib: bitmap: make the start index of bitmap_clear unsigned The compiler can generate slightly smaller and simpler code when it knows that "start" is non-negative. Also, use the names "start" and "len" for the two parameters for consistency with bitmap_set. Signed-off-by: Rasmus Villemoes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/bitmap.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/bitmap.h') diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h index ad2c67d3583e..83c1c7d25073 100644 --- a/include/linux/bitmap.h +++ b/include/linux/bitmap.h @@ -113,7 +113,7 @@ extern int __bitmap_subset(const unsigned long *bitmap1, extern int __bitmap_weight(const unsigned long *bitmap, unsigned int nbits); extern void bitmap_set(unsigned long *map, unsigned int start, int len); -extern void bitmap_clear(unsigned long *map, int start, int nr); +extern void bitmap_clear(unsigned long *map, unsigned int start, int len); extern unsigned long bitmap_find_next_zero_area(unsigned long *map, unsigned long size, unsigned long start, -- cgit v1.2.3 From 9279d3286e10736766edcaf815ae10e00856e448 Mon Sep 17 00:00:00 2001 From: Rasmus Villemoes Date: Wed, 6 Aug 2014 16:10:16 -0700 Subject: lib: bitmap: change parameter of bitmap_*_region to unsigned Changing the pos parameter of __reg_op to unsigned allows the compiler to generate slightly smaller and simpler code. Also update its callers bitmap_*_region to receive and pass unsigned int. The return types of bitmap_find_free_region and bitmap_allocate_region are still int to allow a negative error code to be returned. An int is certainly capable of representing any realistic return value. Signed-off-by: Rasmus Villemoes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/bitmap.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'include/linux/bitmap.h') diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h index 83c1c7d25073..210037833356 100644 --- a/include/linux/bitmap.h +++ b/include/linux/bitmap.h @@ -140,9 +140,9 @@ extern void bitmap_onto(unsigned long *dst, const unsigned long *orig, const unsigned long *relmap, int bits); extern void bitmap_fold(unsigned long *dst, const unsigned long *orig, int sz, int bits); -extern int bitmap_find_free_region(unsigned long *bitmap, int bits, int order); -extern void bitmap_release_region(unsigned long *bitmap, int pos, int order); -extern int bitmap_allocate_region(unsigned long *bitmap, int pos, int order); +extern int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order); +extern void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order); +extern int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order); extern void bitmap_copy_le(void *dst, const unsigned long *src, int nbits); extern int bitmap_ord_to_pos(const unsigned long *bitmap, int n, int bits); -- cgit v1.2.3 From c5341ec8904ebff50f365a2626da6ab525d63b9e Mon Sep 17 00:00:00 2001 From: Rasmus Villemoes Date: Wed, 6 Aug 2014 16:10:20 -0700 Subject: lib: bitmap: add missing mask in bitmap_shift_right There is no guarantee that *src does not contain garbage bits outside the lower nbits, so we need to mask it before the shift-and-assign. Signed-off-by: Rasmus Villemoes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/bitmap.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/bitmap.h') diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h index 210037833356..75df61d9ecfb 100644 --- a/include/linux/bitmap.h +++ b/include/linux/bitmap.h @@ -284,7 +284,7 @@ static inline void bitmap_shift_right(unsigned long *dst, const unsigned long *src, int n, int nbits) { if (small_const_nbits(nbits)) - *dst = *src >> n; + *dst = (*src & BITMAP_LAST_WORD_MASK(nbits)) >> n; else __bitmap_shift_right(dst, src, n, nbits); } -- cgit v1.2.3 From 7e5f97d1927f41affa21aa5b321865ceab1994ce Mon Sep 17 00:00:00 2001 From: Rasmus Villemoes Date: Wed, 6 Aug 2014 16:10:22 -0700 Subject: lib: bitmap: add missing mask in bitmap_and Apparently, bitmap_and is supposed to return whether the new bitmap is empty. But it didn't take potential garbage bits in the last word into account. Signed-off-by: Rasmus Villemoes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/bitmap.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/bitmap.h') diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h index 75df61d9ecfb..3399a9ecd991 100644 --- a/include/linux/bitmap.h +++ b/include/linux/bitmap.h @@ -191,7 +191,7 @@ static inline int bitmap_and(unsigned long *dst, const unsigned long *src1, const unsigned long *src2, unsigned int nbits) { if (small_const_nbits(nbits)) - return (*dst = *src1 & *src2) != 0; + return (*dst = *src1 & *src2 & BITMAP_LAST_WORD_MASK(nbits)) != 0; return __bitmap_and(dst, src1, src2, nbits); } -- cgit v1.2.3 From 74e765319084bd2940a9612ada961f0f7385936c Mon Sep 17 00:00:00 2001 From: Rasmus Villemoes Date: Wed, 6 Aug 2014 16:10:24 -0700 Subject: lib: bitmap: add missing mask in bitmap_andnot Apparently, bitmap_andnot is supposed to return whether the new bitmap is empty. But it didn't take potential garbage bits in the last word into account. Signed-off-by: Rasmus Villemoes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/bitmap.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/bitmap.h') diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h index 3399a9ecd991..e1c8d080c427 100644 --- a/include/linux/bitmap.h +++ b/include/linux/bitmap.h @@ -217,7 +217,7 @@ static inline int bitmap_andnot(unsigned long *dst, const unsigned long *src1, const unsigned long *src2, unsigned int nbits) { if (small_const_nbits(nbits)) - return (*dst = *src1 & ~(*src2)) != 0; + return (*dst = *src1 & ~(*src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0; return __bitmap_andnot(dst, src1, src2, nbits); } -- cgit v1.2.3