[PATCH v2 31/51] fs/buffer.c: use bvec iterator to truncate the bio
STALE3382d
From: Ming Lei <hidden>
Date: 2017-06-26 12:10:14
Also in:
linux-fsdevel, linux-mm, lkml
Subsystem:
filesystems (vfs and infrastructure), the rest · Maintainers:
Alexander Viro, Christian Brauner, Linus Torvalds
Revision v2 of 5 in this series.
Revisions (5)
Once multipage bvec is enabled, the last bvec may include more than one page, this patch use bvec_get_last_page() to truncate the bio. Signed-off-by: Ming Lei <redacted> --- fs/buffer.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/fs/buffer.c b/fs/buffer.c
index 1910f539770b..53b8a29f4525 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c@@ -3055,8 +3055,7 @@ void guard_bio_eod(int op, struct bio *bio) unsigned truncated_bytes; /* * It is safe to truncate the last bvec in the following way - * even though multipage bvec is supported, but we need to - * fix the parameters passed to zero_user(). + * even though multipage bvec is supported. */ struct bio_vec *bvec = &bio->bi_io_vec[bio->bi_vcnt - 1];
@@ -3085,7 +3084,10 @@ 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; + + bvec_get_last_page(bvec, &bv); + zero_user(bv.bv_page, bv.bv_offset + bv.bv_len, truncated_bytes); } }
--
2.9.4