[PATCH 02/12] xfs: simplify xfs_chain_bio

Christoph Hellwig
2019-06-24T05:53:07Z

Move setting up operation and write hint to xfs_alloc_ioend, and
then just copy over all needed information from the previous bio
in xfs_chain_bio and stop passing various parameters to it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
fs/xfs/xfs_aops.c | 35 +++++++++++++++++------------------
1 file changed, 17 insertions(+), 18 deletions(-)

diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c
index a6f0f4761a37..9cceb90e77c5 100644
--- a/fs/xfs/xfs_aops.c
+++ b/fs/xfs/xfs_aops.c
@@ -665,7 +665,6 @@ xfs_submit_ioend(

ioend->io_bio->bi_private = ioend;
ioend->io_bio->bi_end_io = xfs_end_bio;
- ioend->io_bio->bi_opf = REQ_OP_WRITE | wbc_to_write_flags(wbc);

/*
* If we are failing the IO now, just mark the ioend with an
@@ -679,7 +678,6 @@ xfs_submit_ioend(
return status;
}

- ioend->io_bio->bi_write_hint = ioend->io_inode->i_write_hint;
submit_bio(ioend->io_bio);
return 0;
}
@@ -691,7 +689,8 @@ xfs_alloc_ioend(
xfs_exntst_t state,
xfs_off_t offset,
struct block_device *bdev,
- sector_t sector)
+ sector_t sector,
+ struct writeback_control *wbc)
{
struct xfs_ioend *ioend;
struct bio *bio;
@@ -699,6 +698,8 @@ xfs_alloc_ioend(
bio = bio_alloc_bioset(GFP_NOFS, BIO_MAX_PAGES, &xfs_ioend_bioset);
bio_set_dev(bio, bdev);
bio->bi_iter.bi_sector = sector;
+ bio->bi_opf = REQ_OP_WRITE | wbc_to_write_flags(wbc);
+ bio->bi_write_hint = inode->i_write_hint;

ioend = container_of(bio, struct xfs_ioend, io_inline_bio);
INIT_LIST_HEAD(&ioend->io_list);
@@ -719,24 +720,22 @@ xfs_alloc_ioend(
* so that the bi_private linkage is set up in the right direction for the
* traversal in xfs_destroy_ioend().
*/
-static void
+static struct bio *
xfs_chain_bio(
- struct xfs_ioend *ioend,
- struct writeback_control *wbc,
- struct block_device *bdev,
- sector_t sector)
+ struct bio *prev)
{
struct bio *new;

new = bio_alloc(GFP_NOFS, BIO_MAX_PAGES);
- bio_set_dev(new, bdev);
- new->bi_iter.bi_sector = sector;
- bio_chain(ioend->io_bio, new);
- bio_get(ioend->io_bio); /* for xfs_destroy_ioend */
- ioend->io_bio->bi_opf = REQ_OP_WRITE | wbc_to_write_flags(wbc);
- ioend->io_bio->bi_write_hint = ioend->io_inode->i_write_hint;
- submit_bio(ioend->io_bio);
- ioend->io_bio = new;
+ bio_copy_dev(new, prev);
+ new->bi_iter.bi_sector = bio_end_sector(prev);
+ new->bi_opf = prev->bi_opf;
+ new->bi_write_hint = prev->bi_write_hint;
+
+ bio_chain(prev, new);
+ bio_get(prev); /* for xfs_destroy_ioend */
+ submit_bio(prev);
+ return new;
}

/*
@@ -771,14 +770,14 @@ xfs_add_to_ioend(
if (wpc->ioend)
list_add(&wpc->ioend->io_list, iolist);
wpc->ioend = xfs_alloc_ioend(inode, wpc->fork,
- wpc->imap.br_state, offset, bdev, sector);
+ wpc->imap.br_state, offset, bdev, sector, wbc);
}

if (!__bio_try_merge_page(wpc->ioend->io_bio, page, len, poff, true)) {
if (iop)
atomic_inc(&iop->write_count);
if (bio_full(wpc->ioend->io_bio))
- xfs_chain_bio(wpc->ioend, wbc, bdev, sector);
+ wpc->ioend->io_bio = xfs_chain_bio(wpc->ioend->io_bio);
bio_add_page(wpc->ioend->io_bio, page, len, poff);
}

--
2.20.1