dm bufio: subtract the number of initial sectors in dm_bufio_get_devi…

…ce_size dm_bufio_get_device_size returns the device size in blocks. Before returning the value, we must subtract the nubmer of starting sectors. The number of starting sectors 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 change has no effect. However, an upcoming dm-verity-fec fix needs this change. Signed-off-by: Mikulas Patocka <[email protected]> Reviewed-by: Milan Broz <[email protected]> Cc: [email protected] Signed-off-by: Mike Snitzer <[email protected]>
niw · Mar 4, 2021 · a14e5ec · a14e5ec
1 parent a666e5c
commit a14e5ec
Showing 1 changed file with 4 additions and 0 deletions.
diff --git 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