6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Kemeng Shi <shikemeng@xxxxxxxxxxxxxxx> [ Upstream commit 08470a98a7d7e32c787b23b87353f13b03c23195 ] Rewrite sbitmap_find_bit_in_index as following: 1. Rename sbitmap_find_bit_in_index to sbitmap_find_bit_in_word 2. Accept "struct sbitmap_word *" directly instead of accepting "struct sbitmap *" and "int index" to get "struct sbitmap_word *". 3. Accept depth/shallow_depth and wrap for __sbitmap_get_word from caller to support need of both __sbitmap_get_shallow and __sbitmap_get. With helper function sbitmap_find_bit_in_word, we can remove repeat code in __sbitmap_get_shallow to find bit considring deferred clear. Reviewed-by: Jan Kara <jack@xxxxxxx> Signed-off-by: Kemeng Shi <shikemeng@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20230116205059.3821738-4-shikemeng@xxxxxxxxxxxxxxx Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Stable-dep-of: 72d04bdcf3f7 ("sbitmap: fix io hung due to race on sbitmap_word::cleared") Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- lib/sbitmap.c | 30 +++++++++++++++--------------- 1 file changed, 15 insertions(+), 15 deletions(-) diff --git a/lib/sbitmap.c b/lib/sbitmap.c index b9dd0a0a28f89..b942f2ba9a415 100644 --- a/lib/sbitmap.c +++ b/lib/sbitmap.c @@ -167,15 +167,16 @@ static int __sbitmap_get_word(unsigned long *word, unsigned long depth, return nr; } -static int sbitmap_find_bit_in_index(struct sbitmap *sb, int index, - unsigned int alloc_hint) +static int sbitmap_find_bit_in_word(struct sbitmap_word *map, + unsigned int depth, + unsigned int alloc_hint, + bool wrap) { - struct sbitmap_word *map = &sb->map[index]; int nr; do { - nr = __sbitmap_get_word(&map->word, __map_depth(sb, index), - alloc_hint, !sb->round_robin); + nr = __sbitmap_get_word(&map->word, depth, + alloc_hint, wrap); if (nr != -1) break; if (!sbitmap_deferred_clear(map)) @@ -203,7 +204,9 @@ static int __sbitmap_get(struct sbitmap *sb, unsigned int alloc_hint) alloc_hint = 0; for (i = 0; i < sb->map_nr; i++) { - nr = sbitmap_find_bit_in_index(sb, index, alloc_hint); + nr = sbitmap_find_bit_in_word(&sb->map[index], + __map_depth(sb, index), + alloc_hint, !sb->round_robin); if (nr != -1) { nr += index << sb->shift; break; @@ -246,20 +249,17 @@ static int __sbitmap_get_shallow(struct sbitmap *sb, alloc_hint = SB_NR_TO_BIT(sb, alloc_hint); for (i = 0; i < sb->map_nr; i++) { -again: - nr = __sbitmap_get_word(&sb->map[index].word, - min_t(unsigned int, - __map_depth(sb, index), - shallow_depth), - alloc_hint, true); + nr = sbitmap_find_bit_in_word(&sb->map[index], + min_t(unsigned int, + __map_depth(sb, index), + shallow_depth), + alloc_hint, true); + if (nr != -1) { nr += index << sb->shift; break; } - if (sbitmap_deferred_clear(&sb->map[index])) - goto again; - /* Jump to next index. */ alloc_hint = 0; if (++index >= sb->map_nr) -- 2.43.0
