[PATCH RFC 09/11] btrfs: remove bio split operations in btrfs_submit_direct()

Qu Wenruo
2021-11-28T05:55:34Z

Since btrfs_map_bio() will handle the split, there is no need to do the
split in btrfs_submit_direct() anymore.

Signed-off-by: Qu Wenruo <wqu@suse.com>
---
fs/btrfs/inode.c | 116 +++++++++--------------------------------------
1 file changed, 22 insertions(+), 94 deletions(-)

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 1bf56c2b4bd9..24c8bb6d8543 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -8202,22 +8202,16 @@ static void btrfs_end_dio_bio(struct bio *bio)
}

static inline blk_status_t btrfs_submit_dio_bio(struct bio *bio,
- struct inode *inode, u64 file_offset, int async_submit)
+ struct inode *inode, u64 file_offset)
{
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
struct btrfs_dio_private *dip = bio->bi_private;
bool write = btrfs_op(bio) == BTRFS_MAP_WRITE;
+ bool async_submit;
blk_status_t ret;

- /*
- * Check btrfs_submit_data_bio() for rules about async submit.
- *
- * The only exception is for RAID56, when there are more than one bios
- * to submit, async submit seems to make it harder to collect csums
- * for the full stripe.
- */
- if (async_submit)
- async_submit = !atomic_read(&BTRFS_I(inode)->sync_writers);
+ /* Check btrfs_submit_data_bio() for rules about async submit. */
+ async_submit = !atomic_read(&BTRFS_I(inode)->sync_writers);

if (!write)
btrfs_bio(bio)->endio_type = BTRFS_WQ_ENDIO_DATA;
@@ -8291,20 +8285,9 @@ static void btrfs_submit_direct(const struct iomap_iter *iter,
{
struct inode *inode = iter->inode;
const bool write = (btrfs_op(dio_bio) == BTRFS_MAP_WRITE);
- struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
- const bool raid56 = (btrfs_data_alloc_profile(fs_info) &
- BTRFS_BLOCK_GROUP_RAID56_MASK);
struct btrfs_dio_private *dip;
struct bio *bio;
- u64 start_sector;
- int async_submit = 0;
- u64 submit_len;
- u64 clone_offset = 0;
- u64 clone_len;
- u64 logical;
- int ret;
blk_status_t status;
- struct btrfs_io_geometry geom;
struct btrfs_dio_data *dio_data = iter->iomap.private;
struct extent_map *em = NULL;

@@ -8331,84 +8314,29 @@ static void btrfs_submit_direct(const struct iomap_iter *iter,
goto out_err;
}

- start_sector = dio_bio->bi_iter.bi_sector;
- submit_len = dio_bio->bi_iter.bi_size;
-
- do {
- logical = start_sector << 9;
- em = btrfs_get_chunk_map(fs_info, logical, submit_len);
- if (IS_ERR(em)) {
- status = errno_to_blk_status(PTR_ERR(em));
- em = NULL;
- goto out_err_em;
- }
- ret = btrfs_get_io_geometry(fs_info, em, btrfs_op(dio_bio),
- logical, &geom);
- if (ret) {
- status = errno_to_blk_status(ret);
- goto out_err_em;
- }
-
- clone_len = min(submit_len, geom.len);
- ASSERT(clone_len <= UINT_MAX);
-
- /*
- * This will never fail as it's passing GPF_NOFS and
- * the allocation is backed by btrfs_bioset.
- */
- bio = btrfs_bio_clone_partial(dio_bio, clone_offset, clone_len);
- bio->bi_private = dip;
- bio->bi_end_io = btrfs_end_dio_bio;
-
- if (bio_op(bio) == REQ_OP_ZONE_APPEND) {
- status = extract_ordered_extent(BTRFS_I(inode), bio,
- file_offset);
- if (status) {
- bio_put(bio);
- goto out_err;
- }
- }
-
- ASSERT(submit_len >= clone_len);
- submit_len -= clone_len;
-
- /*
- * Increase the count before we submit the bio so we know
- * the end IO handler won't happen before we increase the
- * count. Otherwise, the dip might get freed before we're
- * done setting it up.
- *
- * We transfer the initial reference to the last bio, so we
- * don't need to increment the reference count for the last one.
- */
- if (submit_len > 0) {
- refcount_inc(&dip->refs);
- /*
- * If we are submitting more than one bio, submit them
- * all asynchronously. The exception is RAID 5 or 6, as
- * asynchronous checksums make it difficult to collect
- * full stripe writes.
- */
- if (!raid56)
- async_submit = 1;
- }
+ /*
+ * This will never fail as it's passing GPF_NOFS and
+ * the allocation is backed by btrfs_bioset.
+ */
+ bio = btrfs_bio_clone(dio_bio);
+ bio->bi_private = dip;
+ bio->bi_end_io = btrfs_end_dio_bio;

- status = btrfs_submit_dio_bio(bio, inode, file_offset,
- async_submit);
+ if (bio_op(bio) == REQ_OP_ZONE_APPEND) {
+ status = extract_ordered_extent(BTRFS_I(inode), bio,
+ file_offset);
if (status) {
bio_put(bio);
- if (submit_len > 0)
- refcount_dec(&dip->refs);
- goto out_err_em;
+ goto out_err;
}
+ }

- dio_data->submitted += clone_len;
- clone_offset += clone_len;
- start_sector += clone_len >> 9;
- file_offset += clone_len;
-
- free_extent_map(em);
- } while (submit_len > 0);
+ status = btrfs_submit_dio_bio(bio, inode, file_offset);
+ if (status) {
+ bio_put(bio);
+ goto out_err_em;
+ }
+ dio_data->submitted += dio_bio->bi_iter.bi_size;
return;

out_err_em:
--
2.34.0