From: Ming Lei <ming.lei@redhat.com>
To: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
Ming Lei <ming.lei@redhat.com>, Christoph Hellwig <hch@lst.de>
Subject: [PATCH V9 02/19] block: introduce bio_for_each_bvec()
Date: Tue, 13 Nov 2018 23:14:48 +0800 [thread overview]
Message-ID: <20181113151505.15498-3-ming.lei@redhat.com> (raw)
In-Reply-To: <20181113151505.15498-1-ming.lei@redhat.com>
This helper is used for iterating over multi-page bvec for bio
split & merge code.
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
---
include/linux/bio.h | 34 +++++++++++++++++++++++++++++++---
include/linux/bvec.h | 36 ++++++++++++++++++++++++++++++++----
2 files changed, 63 insertions(+), 7 deletions(-)
diff --git a/include/linux/bio.h b/include/linux/bio.h
index 056fb627edb3..1f0dcf109841 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -76,6 +76,9 @@
#define bio_data_dir(bio) \
(op_is_write(bio_op(bio)) ? WRITE : READ)
+#define bio_iter_mp_iovec(bio, iter) \
+ mp_bvec_iter_bvec((bio)->bi_io_vec, (iter))
+
/*
* Check whether this bio carries any data or not. A NULL bio is allowed.
*/
@@ -135,18 +138,33 @@ static inline bool bio_full(struct bio *bio)
#define bio_for_each_segment_all(bvl, bio, i) \
for (i = 0, bvl = (bio)->bi_io_vec; i < (bio)->bi_vcnt; i++, bvl++)
-static inline void bio_advance_iter(struct bio *bio, struct bvec_iter *iter,
- unsigned bytes)
+static inline void __bio_advance_iter(struct bio *bio, struct bvec_iter *iter,
+ unsigned bytes, bool mp)
{
iter->bi_sector += bytes >> 9;
if (bio_no_advance_iter(bio))
iter->bi_size -= bytes;
else
- bvec_iter_advance(bio->bi_io_vec, iter, bytes);
+ if (!mp)
+ bvec_iter_advance(bio->bi_io_vec, iter, bytes);
+ else
+ mp_bvec_iter_advance(bio->bi_io_vec, iter, bytes);
/* TODO: It is reasonable to complete bio with error here. */
}
+static inline void bio_advance_iter(struct bio *bio, struct bvec_iter *iter,
+ unsigned bytes)
+{
+ __bio_advance_iter(bio, iter, bytes, false);
+}
+
+static inline void bio_advance_mp_iter(struct bio *bio, struct bvec_iter *iter,
+ unsigned bytes)
+{
+ __bio_advance_iter(bio, iter, bytes, true);
+}
+
#define __bio_for_each_segment(bvl, bio, iter, start) \
for (iter = (start); \
(iter).bi_size && \
@@ -156,6 +174,16 @@ static inline void bio_advance_iter(struct bio *bio, struct bvec_iter *iter,
#define bio_for_each_segment(bvl, bio, iter) \
__bio_for_each_segment(bvl, bio, iter, (bio)->bi_iter)
+#define __bio_for_each_bvec(bvl, bio, iter, start) \
+ for (iter = (start); \
+ (iter).bi_size && \
+ ((bvl = bio_iter_mp_iovec((bio), (iter))), 1); \
+ bio_advance_mp_iter((bio), &(iter), (bvl).bv_len))
+
+/* returns one real segment(multipage bvec) each time */
+#define bio_for_each_bvec(bvl, bio, iter) \
+ __bio_for_each_bvec(bvl, bio, iter, (bio)->bi_iter)
+
#define bio_iter_last(bvec, iter) ((iter).bi_size == (bvec).bv_len)
static inline unsigned bio_segments(struct bio *bio)
diff --git a/include/linux/bvec.h b/include/linux/bvec.h
index 8ef904a50577..3d61352cd8cf 100644
--- a/include/linux/bvec.h
+++ b/include/linux/bvec.h
@@ -124,8 +124,16 @@ struct bvec_iter {
.bv_offset = bvec_iter_offset((bvec), (iter)), \
})
-static inline bool bvec_iter_advance(const struct bio_vec *bv,
- struct bvec_iter *iter, unsigned bytes)
+#define mp_bvec_iter_bvec(bvec, iter) \
+((struct bio_vec) { \
+ .bv_page = mp_bvec_iter_page((bvec), (iter)), \
+ .bv_len = mp_bvec_iter_len((bvec), (iter)), \
+ .bv_offset = mp_bvec_iter_offset((bvec), (iter)), \
+})
+
+static inline bool __bvec_iter_advance(const struct bio_vec *bv,
+ struct bvec_iter *iter,
+ unsigned bytes, bool mp)
{
if (WARN_ONCE(bytes > iter->bi_size,
"Attempted to advance past end of bvec iter\n")) {
@@ -134,8 +142,14 @@ static inline bool bvec_iter_advance(const struct bio_vec *bv,
}
while (bytes) {
- unsigned iter_len = bvec_iter_len(bv, *iter);
- unsigned len = min(bytes, iter_len);
+ unsigned len;
+
+ if (mp)
+ len = mp_bvec_iter_len(bv, *iter);
+ else
+ len = bvec_iter_len(bv, *iter);
+
+ len = min(bytes, len);
bytes -= len;
iter->bi_size -= len;
@@ -173,6 +187,20 @@ static inline bool bvec_iter_rewind(const struct bio_vec *bv,
return true;
}
+static inline bool bvec_iter_advance(const struct bio_vec *bv,
+ struct bvec_iter *iter,
+ unsigned bytes)
+{
+ return __bvec_iter_advance(bv, iter, bytes, false);
+}
+
+static inline bool mp_bvec_iter_advance(const struct bio_vec *bv,
+ struct bvec_iter *iter,
+ unsigned bytes)
+{
+ return __bvec_iter_advance(bv, iter, bytes, true);
+}
+
#define for_each_bvec(bvl, bio_vec, iter, start) \
for (iter = (start); \
(iter).bi_size && \
--
2.9.5
next prev parent reply other threads:[~2018-11-13 15:15 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-11-13 15:14 [PATCH V9 00/19] block: support multi-page bvec Ming Lei
2018-11-13 15:14 ` [PATCH V9 01/19] block: introduce multi-page page bvec helpers Ming Lei
2018-11-13 15:14 ` Ming Lei [this message]
2018-11-13 15:14 ` [PATCH V9 03/19] block: use bio_for_each_bvec() to compute multi-page bvec count Ming Lei
2018-11-13 15:14 ` [PATCH V9 04/19] block: use bio_for_each_bvec() to map sg Ming Lei
2018-11-13 15:14 ` [PATCH V9 05/19] block: introduce bvec_last_segment() Ming Lei
2018-11-13 15:14 ` [PATCH V9 06/19] fs/buffer.c: use bvec iterator to truncate the bio Ming Lei
2018-11-13 15:14 ` [PATCH V9 07/19] btrfs: use bvec_last_segment to get bio's last page Ming Lei
2018-11-13 15:14 ` [PATCH V9 08/19] btrfs: move bio_pages_all() to btrfs Ming Lei
2018-11-13 15:14 ` [PATCH V9 09/19] block: introduce bio_bvecs() Ming Lei
2018-11-13 15:14 ` [PATCH V9 10/19] block: loop: pass multi-page bvec to iov_iter Ming Lei
2018-11-13 15:14 ` [PATCH V9 11/19] bcache: avoid to use bio_for_each_segment_all() in bch_bio_alloc_pages() Ming Lei
2018-11-13 15:14 ` [PATCH V9 12/19] block: allow bio_for_each_segment_all() to iterate over multi-page bvec Ming Lei
2018-11-13 15:14 ` [PATCH V9 13/19] iomap & xfs: only account for new added page Ming Lei
2018-11-13 15:15 ` [PATCH V9 14/19] block: enable multipage bvecs Ming Lei
2018-11-13 15:15 ` [PATCH V9 15/19] block: always define BIO_MAX_PAGES as 256 Ming Lei
2018-11-13 15:15 ` [PATCH V9 16/19] block: document usage of bio iterator helpers Ming Lei
2018-11-13 15:15 ` [PATCH V9 17/19] block: don't use bio->bi_vcnt to figure out segment number Ming Lei
2018-11-13 15:15 ` [PATCH V9 18/19] block: kill QUEUE_FLAG_NO_SG_MERGE Ming Lei
2018-11-13 15:15 ` [PATCH V9 19/19] block: kill BLK_MQ_F_SG_MERGE Ming Lei
2018-11-14 2:44 ` [PATCH V9 00/19] block: support multi-page bvec Dave Chinner
2018-11-14 2:57 ` Ming Lei
2018-11-14 15:22 ` Christoph Hellwig
2018-11-15 9:35 ` Ming Lei
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20181113151505.15498-3-ming.lei@redhat.com \
--to=ming.lei@redhat.com \
--cc=axboe@kernel.dk \
--cc=hch@lst.de \
--cc=linux-block@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).