diff options
| author | Jérôme Glisse <jglisse@redhat.com> | 2019-04-17 12:54:19 -0400 |
|---|---|---|
| committer | Jérôme Glisse <jglisse@redhat.com> | 2019-05-22 17:19:11 -0400 |
| commit | f66327493a574f7c100c7c8834d4b96dafa733fa (patch) | |
| tree | d3b02c07ac8bc4f05e91ffb426e9d4b4bc49b7f9 | |
| parent | 9a2c97c07d4542fc3b6a89efb076fedde35e8948 (diff) | |
block/bio: export bio_release_pages()
Releasing all the pages in a bio is a common pattern within
the kernel so instead of having same code duplicated in few
places just expose this function.
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-block@vger.kernel.org
Cc: linux-mm@kvack.org
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Boaz Harrosh <boaz@plexistor.com>
| -rw-r--r-- | block/bio.c | 16 | ||||
| -rw-r--r-- | include/linux/bio.h | 1 |
2 files changed, 16 insertions, 1 deletions
diff --git a/block/bio.c b/block/bio.c index 586e11dbf507..69654714d629 100644 --- a/block/bio.c +++ b/block/bio.c @@ -855,7 +855,20 @@ static void bio_get_pages(struct bio *bio) get_page(bvec->bv_page); } -static void bio_release_pages(struct bio *bio, bool from_gup) +/** + * bio_release_pages() - release all pages in a bio + * @bio: the bio struct containing the pages to release + * @from_gup: did the pages in the bio came from GUP (get_user_pages*()) + * + * This will release page reference for all the pages in the bio. + * + * We also need to know if the pages in the bio are coming from GUP or not as + * GUPed page need to be release through specific put_user_page(). Please see + * Documentation/vm/get_user_pages.rst for details on that. Rules of dumb is + * that if the bio has been populated with the help of iov_iter_get_pages*() + * then it might have GUPed pages (see iov_iter_get_pages_use_gup()) + */ +void bio_release_pages(struct bio *bio, bool from_gup) { struct bio_vec *bvec; struct bvec_iter_all iter_all; @@ -868,6 +881,7 @@ static void bio_release_pages(struct bio *bio, bool from_gup) put_page(bvec->bv_page); } } +EXPORT_SYMBOL_GPL(bio_release_pages); static int __bio_iov_bvec_add_pages(struct bio *bio, struct iov_iter *iter) { diff --git a/include/linux/bio.h b/include/linux/bio.h index 06d334fe38f9..ed861951db45 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -436,6 +436,7 @@ extern struct bio *bio_map_kern(struct request_queue *, void *, unsigned int, extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int, gfp_t, int); extern void bio_set_pages_dirty(struct bio *bio); +extern void bio_release_pages(struct bio *bio, bool from_gup); extern void bio_check_pages_dirty(struct bio *bio, bool from_gup); void generic_start_io_acct(struct request_queue *q, int op, |