dm cache: fix corruption seen when using cache > 2TB

commit ca763d0a53b264a650342cee206512bc92ac7050 upstream.

A rounding bug due to compiler generated temporary being 32bit was found
in remap_to_cache().  A localized cast in remap_to_cache() fixes the
corruption but this preferred fix (changing from uint32_t to sector_t)
eliminates potential for future rounding errors elsewhere.

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Joe Thornber 2017-02-09 11:46:18 -05:00 committed by Greg Kroah-Hartman
parent f0ae01568e
commit fdea1f9721

View File

@ -251,7 +251,7 @@ struct cache {
/*
* Fields for converting from sectors to blocks.
*/
uint32_t sectors_per_block;
sector_t sectors_per_block;
int sectors_per_block_shift;
spinlock_t lock;
@ -3547,11 +3547,11 @@ static void cache_status(struct dm_target *ti, status_type_t type,
residency = policy_residency(cache->policy);
DMEMIT("%u %llu/%llu %u %llu/%llu %u %u %u %u %u %u %lu ",
DMEMIT("%u %llu/%llu %llu %llu/%llu %u %u %u %u %u %u %lu ",
(unsigned)DM_CACHE_METADATA_BLOCK_SIZE,
(unsigned long long)(nr_blocks_metadata - nr_free_blocks_metadata),
(unsigned long long)nr_blocks_metadata,
cache->sectors_per_block,
(unsigned long long)cache->sectors_per_block,
(unsigned long long) from_cblock(residency),
(unsigned long long) from_cblock(cache->cache_size),
(unsigned) atomic_read(&cache->stats.read_hit),