[PATCH 05/12] block_dev: convert put_page() to put_user_page*()

john.hubbard
2019-07-24T04:25:35Z

From: Jérôme Glisse <jglisse@redhat.com>

For pages that were retained via get_user_pages*(), release those pages
via the new put_user_page*() routines, instead of via put_page() or
release_pages().

This is part a tree-wide conversion, as described in commit fc1d8e7cca2d
("mm: introduce put_user_page*(), placeholder versions").

Changes from Jérôme's original patch:

* reworked to be compatible with recent bio_release_pages() changes.

Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-block@vger.kernel.org
Cc: linux-mm@kvack.org
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>
---
block/bio.c | 13 +++++++++++++
fs/block_dev.c | 22 +++++++++++++++++-----
include/linux/bio.h | 8 ++++++++
3 files changed, 38 insertions(+), 5 deletions(-)

diff --git a/block/bio.c b/block/bio.c
index 74f9eba2583b..3b9f66e64bc1 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -1746,6 +1746,19 @@ void bio_check_pages_dirty(struct bio *bio)
__bio_check_pages_dirty(bio, false);
}

+enum bio_rp_flags_t bio_rp_flags(struct iov_iter *iter, bool mark_dirty)
+{
+ enum bio_rp_flags_t flags = BIO_RP_NORMAL;
+
+ if (mark_dirty)
+ flags |= BIO_RP_MARK_DIRTY;
+
+ if (iov_iter_get_pages_use_gup(iter))
+ flags |= BIO_RP_FROM_GUP;
+
+ return flags;
+}
+
void update_io_ticks(struct hd_struct *part, unsigned long now)
{
unsigned long stamp;
diff --git a/fs/block_dev.c b/fs/block_dev.c
index 9fe6616f8788..d53abaf31e54 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -259,7 +259,7 @@ __blkdev_direct_IO_simple(struct kiocb *iocb, struct iov_iter *iter,
}
__set_current_state(TASK_RUNNING);

- bio_release_pages(&bio, bio_rp_dirty_flag(should_dirty));
+ bio_release_pages(&bio, bio_rp_flags(iter, should_dirty));
if (unlikely(bio.bi_status))
ret = blk_status_to_errno(bio.bi_status);

@@ -295,7 +295,7 @@ static int blkdev_iopoll(struct kiocb *kiocb, bool wait)
return blk_poll(q, READ_ONCE(kiocb->ki_cookie), wait);
}

-static void blkdev_bio_end_io(struct bio *bio)
+static void _blkdev_bio_end_io(struct bio *bio, bool from_gup)
{
struct blkdev_dio *dio = bio->bi_private;
bool should_dirty = dio->should_dirty;
@@ -327,13 +327,23 @@ static void blkdev_bio_end_io(struct bio *bio)
}

if (should_dirty) {
- bio_check_pages_dirty(bio);
+ __bio_check_pages_dirty(bio, from_gup);
} else {
- bio_release_pages(bio, BIO_RP_NORMAL);
+ bio_release_pages(bio, bio_rp_gup_flag(from_gup));
bio_put(bio);
}
}

+static void blkdev_bio_end_io(struct bio *bio)
+{
+ _blkdev_bio_end_io(bio, false);
+}
+
+static void blkdev_bio_from_gup_end_io(struct bio *bio)
+{
+ _blkdev_bio_end_io(bio, true);
+}
+
static ssize_t
__blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter, int nr_pages)
{
@@ -380,7 +390,9 @@ __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter, int nr_pages)
bio->bi_iter.bi_sector = pos >> 9;
bio->bi_write_hint = iocb->ki_hint;
bio->bi_private = dio;
- bio->bi_end_io = blkdev_bio_end_io;
+ bio->bi_end_io = iov_iter_get_pages_use_gup(iter) ?
+ blkdev_bio_from_gup_end_io :
+ blkdev_bio_end_io;
bio->bi_ioprio = iocb->ki_ioprio;

ret = bio_iov_iter_get_pages(bio, iter);
diff --git a/include/linux/bio.h b/include/linux/bio.h
index d68a40c2c9d4..b9460d1a4679 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -452,6 +452,13 @@ static inline enum bio_rp_flags_t bio_rp_dirty_flag(bool mark_dirty)
return mark_dirty ? BIO_RP_MARK_DIRTY : BIO_RP_NORMAL;
}

+static inline enum bio_rp_flags_t bio_rp_gup_flag(bool from_gup)
+{
+ return from_gup ? BIO_RP_FROM_GUP : BIO_RP_NORMAL;
+}
+
+enum bio_rp_flags_t bio_rp_flags(struct iov_iter *iter, bool mark_dirty);
+
void bio_release_pages(struct bio *bio, enum bio_rp_flags_t flags);
struct rq_map_data;
extern struct bio *bio_map_user_iov(struct request_queue *,
@@ -463,6 +470,7 @@ 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_check_pages_dirty(struct bio *bio);
+void __bio_check_pages_dirty(struct bio *bio, bool from_gup);

void generic_start_io_acct(struct request_queue *q, int op,
unsigned long sectors, struct hd_struct *part);
--
2.22.0