Re: [PATCH] do_direct_IO: Use inode->i_blkbits to compute block count to be cleaned
From: Jan Kara <jack@suse.cz>
Date: 2017-01-09 20:20:21
Also in:
linux-fsdevel, linuxppc-dev, lkml
On Sun 08-01-17 20:17:10, Chandan Rajendra wrote:
The code currently uses sdio->blkbits to compute the number of blocks to be cleaned. However sdio->blkbits is derived from the logical block size of the underlying block device (Refer to the definition of do_blockdev_direct_IO()). Due to this, generic/299 test would rarely fail when executed on an ext4 filesystem with 64k as the block size and when using a virtio based disk (having 512 byte as the logical block size) inside a kvm guest. This commit fixes the bug by using inode->i_blkbits to compute the number of blocks to be cleaned.
Ah, good catch. You can add: Reviewed-by: Jan Kara <jack@suse.cz> Honza
quoted hunk ↗ jump to hunk
Signed-off-by: Chandan Rajendra <redacted> --- fs/direct-io.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)diff --git a/fs/direct-io.c b/fs/direct-io.c index aeae8c0..b20adf9 100644 --- a/fs/direct-io.c +++ b/fs/direct-io.c@@ -905,6 +905,7 @@ static inline void dio_zero_block(struct dio *dio, struct dio_submit *sdio, static int do_direct_IO(struct dio *dio, struct dio_submit *sdio, struct buffer_head *map_bh) { + const unsigned i_blkbits = dio->inode->i_blkbits; const unsigned blkbits = sdio->blkbits; int ret = 0;@@ -949,7 +950,7 @@ static int do_direct_IO(struct dio *dio, struct dio_submit *sdio, clean_bdev_aliases( map_bh->b_bdev, map_bh->b_blocknr, - map_bh->b_size >> blkbits); + map_bh->b_size >> i_blkbits); } if (!sdio->blkfactor)-- 2.5.5
-- Jan Kara [off-list ref] SUSE Labs, CR