[PATCH V14 09/18] fs/buffer.c: use bvec iterator to truncate the bio
From: Ming Lei <hidden>
Date: 2019-01-21 08:23:16
Also in:
dm-devel, linux-bcache, linux-btrfs, linux-ext4, linux-fsdevel, linux-mm, linux-raid, linux-xfs, lkml
Subsystem:
filesystems (vfs and infrastructure), the rest · Maintainers:
Alexander Viro, Christian Brauner, Linus Torvalds
Once multi-page bvec is enabled, the last bvec may include more than one page, this patch use mp_bvec_last_segment() to truncate the bio. Reviewed-by: Omar Sandoval <redacted> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ming Lei <redacted> --- fs/buffer.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/fs/buffer.c b/fs/buffer.c
index 52d024bfdbc1..817871274c77 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c@@ -3032,7 +3032,10 @@ void guard_bio_eod(int op, struct bio *bio) /* ..and clear the end of the buffer for reads */ if (op == REQ_OP_READ) { - zero_user(bvec->bv_page, bvec->bv_offset + bvec->bv_len, + struct bio_vec bv; + + mp_bvec_last_segment(bvec, &bv); + zero_user(bv.bv_page, bv.bv_offset + bv.bv_len, truncated_bytes); } }
--
2.9.5