From: Ming Lei <tom.leiming@gmail.com>
To: Shaohua Li <shli@kernel.org>, Jens Axboe <axboe@fb.com>,
linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org,
linux-block@vger.kernel.org,
Christoph Hellwig <hch@infradead.org>, NeilBrown <neilb@suse.com>
Cc: Ming Lei <tom.leiming@gmail.com>
Subject: [PATCH 02/17] block: introduce bio_remove_last_page()
Date: Thu, 16 Feb 2017 19:45:32 +0800 [thread overview]
Message-ID: <1487245547-24384-3-git-send-email-tom.leiming@gmail.com> (raw)
In-Reply-To: <1487245547-24384-1-git-send-email-tom.leiming@gmail.com>
MD need this helper to remove the last added page, so introduce
it.
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
---
block/bio.c | 23 +++++++++++++++++++++++
include/linux/bio.h | 1 +
2 files changed, 24 insertions(+)
diff --git a/block/bio.c b/block/bio.c
index 5eec5e08417f..0ce7ffcd7939 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -837,6 +837,29 @@ int bio_add_pc_page(struct request_queue *q, struct bio *bio, struct page
EXPORT_SYMBOL(bio_add_pc_page);
/**
+ * bio_remove_last_page - remove the last added page
+ * @bio: destination bio
+ *
+ * Attempt to remove the last added page from the bio_vec maplist.
+ */
+void bio_remove_last_page(struct bio *bio)
+{
+ /*
+ * cloned bio must not modify vec list
+ */
+ if (WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED)))
+ return;
+
+ if (bio->bi_vcnt > 0) {
+ struct bio_vec *bv = &bio->bi_io_vec[bio->bi_vcnt - 1];
+
+ bio->bi_iter.bi_size -= bv->bv_len;
+ bio->bi_vcnt--;
+ }
+}
+EXPORT_SYMBOL(bio_remove_last_page);
+
+/**
* bio_add_page - attempt to add page to bio
* @bio: destination bio
* @page: page to add
diff --git a/include/linux/bio.h b/include/linux/bio.h
index 3364b3ed90e7..32aeb493d1fe 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -443,6 +443,7 @@ extern void bio_init(struct bio *bio, struct bio_vec *table,
extern void bio_reset(struct bio *);
void bio_chain(struct bio *, struct bio *);
+extern void bio_remove_last_page(struct bio *bio);
extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int);
extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *,
unsigned int, unsigned int);
--
2.7.4
next prev parent reply other threads:[~2017-02-16 11:46 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-02-16 11:45 [PATCH 00/17] md: cleanup on direct access to bvec table Ming Lei
2017-02-16 11:45 ` [PATCH 01/17] block: introduce bio_segments_all() Ming Lei
2017-02-16 11:45 ` Ming Lei [this message]
2017-02-16 12:08 ` [PATCH 02/17] block: introduce bio_remove_last_page() Johannes Thumshirn
2017-02-16 13:30 ` Ming Lei
2017-02-16 13:40 ` Johannes Thumshirn
2017-02-16 13:59 ` Ming Lei
2017-02-16 14:10 ` Johannes Thumshirn
2017-02-16 11:45 ` [PATCH 03/17] md: raid1/raid10: use bio_remove_last_page() Ming Lei
2017-02-16 11:45 ` [PATCH 04/17] md: introduce helpers for dealing with fetch/store preallocated pages in bio Ming Lei
2017-02-16 11:45 ` [PATCH 05/17] md: raid1/raid10: use the introduced helpers Ming Lei
2017-02-16 11:45 ` [PATCH 06/17] md: raid1/raid10: borrow .bi_error as pre-allocated page index Ming Lei
2017-02-16 11:45 ` [PATCH 07/17] md: raid1/raid10: don't use .bi_vcnt to check if all pages are added Ming Lei
2017-02-16 11:45 ` [PATCH 08/17] md: raid1: simplify r1buf_pool_free() Ming Lei
2017-02-16 11:45 ` [PATCH 09/17] md: raid1/raid10: use bio helper in *_pool_free Ming Lei
2017-02-16 11:45 ` [PATCH 10/17] md: raid1: remove direct access to bvec table in fix_sync_read_error Ming Lei
2017-02-16 11:45 ` [PATCH 11/17] md: raid1: use bio helper in process_checks() Ming Lei
2017-02-16 11:45 ` [PATCH 12/17] md: raid1: avoid direct access to bvec table " Ming Lei
2017-02-17 8:33 ` kbuild test robot
2017-02-16 11:45 ` [PATCH 13/17] md: raid1: use bio_segments_all() Ming Lei
2017-02-16 12:35 ` Johannes Thumshirn
2017-02-16 13:32 ` Ming Lei
2017-02-16 13:34 ` Johannes Thumshirn
2017-02-16 13:38 ` Ming Lei
2017-02-16 11:45 ` [PATCH 14/17] md: raid10: avoid direct access to bvec table in sync_request_write() Ming Lei
2017-02-16 11:45 ` [PATCH 15/17] md: raid10: avoid direct access to bvec table in fix_recovery_read_error Ming Lei
2017-02-16 11:45 ` [PATCH 16/17] md: raid10: avoid direct access to bvec table in reshape_request Ming Lei
2017-02-16 11:45 ` [PATCH 17/17] md: raid10: avoid direct access to bvec table in handle_reshape_read_error Ming Lei
2017-02-16 22:16 ` [PATCH 00/17] md: cleanup on direct access to bvec table Shaohua Li
2017-02-17 1:25 ` Ming Lei
2017-02-17 4:16 ` Shaohua Li
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