From: Mikulas Patocka <mpatocka@xxxxxxxxxx> dm_bufio_get_device_size returns returns the device size in blocks. Before returning the value, we must subtract the nubmer of starting sectors. The number of starting sectos may not be divisible by block size. Note that currently, no target is using dm_bufio_set_sector_offset and dm_bufio_get_device_size simultaneously, so this patch has no effect. However, an upcoming patch that fixes dm-verity-fec needs this change. Signed-off-by: Mikulas Patocka <mpatocka@xxxxxxxxxx> Reviewed-by: Milan Broz <gmazyland@xxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx --- drivers/md/dm-bufio.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/md/dm-bufio.c b/drivers/md/dm-bufio.c index fce4cbf9529d..50f3e673729c 100644 --- a/drivers/md/dm-bufio.c +++ b/drivers/md/dm-bufio.c @@ -1526,6 +1526,10 @@ EXPORT_SYMBOL_GPL(dm_bufio_get_block_size); sector_t dm_bufio_get_device_size(struct dm_bufio_client *c) { sector_t s = i_size_read(c->bdev->bd_inode) >> SECTOR_SHIFT; + if (s >= c->start) + s -= c->start; + else + s = 0; if (likely(c->sectors_per_block_bits >= 0)) s >>= c->sectors_per_block_bits; else -- 2.30.1