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block: never take page references for ITER_BVEC

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If we pass pages through an iov_iter we always already have a reference
in the caller.  Thus remove the ITER_BVEC_FLAG_NO_REF and don't take
reference to pages by default for bvec backed iov_iters.

Reviewed-by: Minwoo Im <minwoo.im.dev@gmail.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Christoph Hellwig
2019-06-26 15:49:28 +02:00
committed by Jens Axboe
parent d7c8aa85ed
commit b620743077
4 changed files with 6 additions and 37 deletions
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10
include/linux/uio.h
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@@ -19,9 +19,6 @@ struct kvec {
};
enum iter_type {
/* set if ITER_BVEC doesn't hold a bv_page ref */
ITER_BVEC_FLAG_NO_REF = 2,
/* iter types */
ITER_IOVEC = 4,
ITER_KVEC = 8,
@@ -56,7 +53,7 @@ struct iov_iter {
static inline enum iter_type iov_iter_type(const struct iov_iter *i)
{
return i->type & ~(READ | WRITE | ITER_BVEC_FLAG_NO_REF);
return i->type & ~(READ | WRITE);
}
static inline bool iter_is_iovec(const struct iov_iter *i)
@@ -89,11 +86,6 @@ static inline unsigned char iov_iter_rw(const struct iov_iter *i)
return i->type & (READ | WRITE);
}
static inline bool iov_iter_bvec_no_ref(const struct iov_iter *i)
{
return (i->type & ITER_BVEC_FLAG_NO_REF) != 0;
}
/*
* Total number of bytes covered by an iovec.
*