From 428bc098635680a664779f26f24fe9197d186172 Mon Sep 17 00:00:00 2001 From: Alexander Lobakin Date: Mon, 11 Jul 2022 20:09:29 +0200 Subject: lib/bitmap: fix off-by-one in bitmap_to_arr64() GENMASK*() family takes the first and the last bits of the mask *including* them. So, with the current code bitmap_to_arr64() doesn't clear the tail properly: nbits % exp mask must be 1 GENMASK(1, 0) 0x3 0x1 ... 63 GENMASK(63, 0) 0xffffffffffffffff 0x7fffffffffffffff This was found by making the function always available instead of 32-bit BE systems only (for reusing in some new functionality). Turn the number of bits into the last bit set by subtracting 1. @nbits is already checked to be positive beforehand. Fixes: 0a97953fd221 ("lib: add bitmap_{from,to}_arr64") Signed-off-by: Alexander Lobakin Reviewed-by: Andy Shevchenko Signed-off-by: Yury Norov --- lib/bitmap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'lib/bitmap.c') diff --git a/lib/bitmap.c b/lib/bitmap.c index b18e31ea6e66..e903e13c62e1 100644 --- a/lib/bitmap.c +++ b/lib/bitmap.c @@ -1564,7 +1564,7 @@ void bitmap_to_arr64(u64 *buf, const unsigned long *bitmap, unsigned int nbits) /* Clear tail bits in the last element of array beyond nbits. */ if (nbits % 64) - buf[-1] &= GENMASK_ULL(nbits % 64, 0); + buf[-1] &= GENMASK_ULL((nbits - 1) % 64, 0); } EXPORT_SYMBOL(bitmap_to_arr64); #endif -- cgit From e2863a78593d638d3924a6f67900c4820034f349 Mon Sep 17 00:00:00 2001 From: Yury Norov Date: Fri, 1 Jul 2022 05:54:24 -0700 Subject: lib/bitmap: change return types to bool where appropriate Some bitmap functions return boolean results in int variables. Fix it by changing return types to bool. Signed-off-by: Yury Norov --- lib/bitmap.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'lib/bitmap.c') diff --git a/lib/bitmap.c b/lib/bitmap.c index e903e13c62e1..9bc80f5bf149 100644 --- a/lib/bitmap.c +++ b/lib/bitmap.c @@ -237,7 +237,7 @@ void bitmap_cut(unsigned long *dst, const unsigned long *src, } EXPORT_SYMBOL(bitmap_cut); -int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1, +bool __bitmap_and(unsigned long *dst, const unsigned long *bitmap1, const unsigned long *bitmap2, unsigned int bits) { unsigned int k; @@ -275,7 +275,7 @@ void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1, } EXPORT_SYMBOL(__bitmap_xor); -int __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1, +bool __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1, const unsigned long *bitmap2, unsigned int bits) { unsigned int k; -- cgit From 4dea97f8636d0514befc9fc5cf342b351b7d0e20 Mon Sep 17 00:00:00 2001 From: Yury Norov Date: Fri, 1 Jul 2022 05:54:25 -0700 Subject: lib/bitmap: change type of bitmap_weight to unsigned long bitmap_weight() doesn't return negative values, so change it's type to unsigned long. It may help compiler to generate better code and catch bugs. Signed-off-by: Yury Norov --- lib/bitmap.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) (limited to 'lib/bitmap.c') diff --git a/lib/bitmap.c b/lib/bitmap.c index 9bc80f5bf149..2b67cd657692 100644 --- a/lib/bitmap.c +++ b/lib/bitmap.c @@ -333,10 +333,9 @@ bool __bitmap_subset(const unsigned long *bitmap1, } EXPORT_SYMBOL(__bitmap_subset); -int __bitmap_weight(const unsigned long *bitmap, unsigned int bits) +unsigned long __bitmap_weight(const unsigned long *bitmap, unsigned int bits) { - unsigned int k, lim = bits/BITS_PER_LONG; - int w = 0; + unsigned long k, w = 0, lim = bits/BITS_PER_LONG; for (k = 0; k < lim; k++) w += hweight_long(bitmap[k]); -- cgit