The patch below does not apply to the 3.13-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.
thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From e0d849fad746cb36a6822e4595d8ba9bf0adf7fa Mon Sep 17 00:00:00 2001 From: Heinz Mauelshagen <[email protected]> Date: Thu, 27 Feb 2014 22:46:48 +0100 Subject: [PATCH] dm cache: fix truncation bug when mapping I/O to >2TB fast device When remapping a block to the cache's fast device that is larger than 2TB we must not truncate the destination sector to 32bits. The 32bit temporary result of from_cblock() was being overflowed in remap_to_cache() due to the logical left shift. Use an intermediate 64bit type to store the 32bit from_cblock() result to fix the overflow. Signed-off-by: Heinz Mauelshagen <[email protected]> Signed-off-by: Mike Snitzer <[email protected]> Cc: [email protected] diff --git a/drivers/md/dm-cache-target.c b/drivers/md/dm-cache-target.c index db0944465127..1af70145fab9 100644 --- a/drivers/md/dm-cache-target.c +++ b/drivers/md/dm-cache-target.c @@ -671,15 +671,16 @@ static void remap_to_cache(struct cache *cache, struct bio *bio, dm_cblock_t cblock) { sector_t bi_sector = bio->bi_iter.bi_sector; + sector_t block = from_cblock(cblock); bio->bi_bdev = cache->cache_dev->bdev; if (!block_size_is_power_of_two(cache)) bio->bi_iter.bi_sector = - (from_cblock(cblock) * cache->sectors_per_block) + + (block * cache->sectors_per_block) + sector_div(bi_sector, cache->sectors_per_block); else bio->bi_iter.bi_sector = - (from_cblock(cblock) << cache->sectors_per_block_shift) | + (block << cache->sectors_per_block_shift) | (bi_sector & (cache->sectors_per_block - 1)); } -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
