4.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Joe Thornber <e...@redhat.com>

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 <e...@redhat.com>
Signed-off-by: Mike Snitzer <snit...@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>

---
 drivers/md/dm-cache-target.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

--- a/drivers/md/dm-cache-target.c
+++ b/drivers/md/dm-cache-target.c
@@ -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_targe
 
                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),


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