diff mbox series

[09/17] btrfs: add an ordered_extent pointer to struct btrfs_bio

Message ID 20230531075410.480499-10-hch@lst.de (mailing list archive)
State New, archived
Headers show
Series [01/17] btrfs: fix file_offset for REQ_BTRFS_ONE_ORDERED bios that get split | expand

Commit Message

Christoph Hellwig May 31, 2023, 7:54 a.m. UTC 
Add a pointer to the ordered_extent to the existing union in struct
btrfs_bio, so all code dealing with data write bios can just use a
pointer dereference to retrieve the ordered_extent instead of doing
multiple rbtree lookups per I/O.

The reference to this ordered_extent is dropped at end I/O time,
which implies that an extra one must be acquired when the bio is split.
This also requires moving the btrfs_extract_ordered_extent call into
btrfs_split_bio so that the invariant of always having a valid
ordered_extent reference for the btrfs_bio is kept.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
---
 fs/btrfs/bio.c         | 42 ++++++++++++++++++++++++++++++++++++++----
 fs/btrfs/bio.h         |  9 +++------
 fs/btrfs/compression.c |  2 +-
 fs/btrfs/extent_io.c   |  2 +-
 fs/btrfs/inode.c       |  8 +++++---
 5 files changed, 48 insertions(+), 15 deletions(-)
diff mbox series

Patch

diff --git a/fs/btrfs/bio.c b/fs/btrfs/bio.c
index 18afad50a98774..49ab2831483338 100644
--- a/fs/btrfs/bio.c
+++ b/fs/btrfs/bio.c
@@ -33,6 +33,11 @@  static inline bool is_data_bbio(struct btrfs_bio *bbio)
 	return bbio->inode && is_data_inode(&bbio->inode->vfs_inode);
 }
 
+static bool bbio_has_ordered_extent(struct btrfs_bio *bbio)
+{
+	return is_data_bbio(bbio) && btrfs_op(&bbio->bio) == BTRFS_MAP_WRITE;
+}
+
 /*
  * Initialize a btrfs_bio structure.  This skips the embedded bio itself as it
  * is already initialized by the block layer.
@@ -88,11 +93,40 @@  static struct btrfs_bio *btrfs_split_bio(struct btrfs_fs_info *fs_info,
 	bbio->inode = orig_bbio->inode;
 	bbio->file_offset = orig_bbio->file_offset;
 	orig_bbio->file_offset += map_length;
-
+	if (bbio_has_ordered_extent(bbio)) {
+		refcount_inc(&orig_bbio->ordered->refs);
+		bbio->ordered = orig_bbio->ordered;
+	}
 	atomic_inc(&orig_bbio->pending_ios);
 	return bbio;
 }
 
+/* Free a bio that was never submitted to the underlying device */
+static void btrfs_cleanup_bio(struct btrfs_bio *bbio)
+{
+	if (bbio_has_ordered_extent(bbio))
+		btrfs_put_ordered_extent(bbio->ordered);
+	bio_put(&bbio->bio);
+}
+
+static void __btrfs_bio_end_io(struct btrfs_bio *bbio)
+{
+	if (bbio_has_ordered_extent(bbio)) {
+		struct btrfs_ordered_extent *ordered = bbio->ordered;
+
+		bbio->end_io(bbio);
+		btrfs_put_ordered_extent(ordered);
+	} else {
+		bbio->end_io(bbio);
+	}
+}
+
+void btrfs_bio_end_io(struct btrfs_bio *bbio, blk_status_t status)
+{
+	bbio->bio.bi_status = status;
+	__btrfs_bio_end_io(bbio);
+}
+
 static void btrfs_orig_write_end_io(struct bio *bio);
 
 static void btrfs_bbio_propagate_error(struct btrfs_bio *bbio,
@@ -121,12 +155,12 @@  static void btrfs_orig_bbio_end_io(struct btrfs_bio *bbio)
 
 		if (bbio->bio.bi_status)
 			btrfs_bbio_propagate_error(bbio, orig_bbio);
-		bio_put(&bbio->bio);
+		btrfs_cleanup_bio(bbio);
 		bbio = orig_bbio;
 	}
 
 	if (atomic_dec_and_test(&bbio->pending_ios))
-		bbio->end_io(bbio);
+		__btrfs_bio_end_io(bbio);
 }
 
 static int next_repair_mirror(struct btrfs_failed_bio *fbio, int cur_mirror)
@@ -679,7 +713,7 @@  static bool btrfs_submit_chunk(struct btrfs_bio *bbio, int mirror_num)
 
 fail_put_bio:
 	if (map_length < length)
-		bio_put(bio);
+		btrfs_cleanup_bio(bbio);
 fail:
 	btrfs_bio_counter_dec(fs_info);
 	btrfs_bio_end_io(orig_bbio, ret);
diff --git a/fs/btrfs/bio.h b/fs/btrfs/bio.h
index 52e7962103fff2..ca79decee0607f 100644
--- a/fs/btrfs/bio.h
+++ b/fs/btrfs/bio.h
@@ -50,11 +50,13 @@  struct btrfs_bio {
 
 		/*
 		 * For data writes:
+		 * - ordered extent covering the bio
 		 * - pointer to the checksums for this bio
 		 * - original physical address from the allocator
 		 *   (for zone append only)
 		 */
 		struct {
+			struct btrfs_ordered_extent *ordered;
 			struct btrfs_ordered_sum *sums;
 			u64 orig_physical;
 		};
@@ -95,12 +97,7 @@  void btrfs_bio_init(struct btrfs_bio *bbio, struct btrfs_fs_info *fs_info,
 struct btrfs_bio *btrfs_bio_alloc(unsigned int nr_vecs, blk_opf_t opf,
 				  struct btrfs_fs_info *fs_info,
 				  btrfs_bio_end_io_t end_io, void *private);
-
-static inline void btrfs_bio_end_io(struct btrfs_bio *bbio, blk_status_t status)
-{
-	bbio->bio.bi_status = status;
-	bbio->end_io(bbio);
-}
+void btrfs_bio_end_io(struct btrfs_bio *bbio, blk_status_t status);
 
 /* Submit using blkcg_punt_bio_submit. */
 #define REQ_BTRFS_CGROUP_PUNT			REQ_FS_PRIVATE
diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index e187ff417370c7..e27f30417cefc8 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -305,10 +305,10 @@  void btrfs_submit_compressed_write(struct btrfs_ordered_extent *ordered,
 	INIT_WORK(&cb->write_end_work, btrfs_finish_compressed_write_work);
 	cb->nr_pages = nr_pages;
 	cb->bbio.bio.bi_iter.bi_sector = ordered->disk_bytenr >> SECTOR_SHIFT;
+	cb->bbio.ordered = ordered;
 	btrfs_add_compressed_bio_pages(cb);
 
 	btrfs_submit_bio(&cb->bbio, 0);
-	btrfs_put_ordered_extent(ordered);
 }
 
 /*
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index af58147851d878..645723d16d5979 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -806,7 +806,7 @@  static void alloc_new_bio(struct btrfs_inode *inode,
 			bio_ctrl->len_to_oe_boundary = min_t(u32, U32_MAX,
 					ordered->file_offset +
 					ordered->disk_num_bytes - file_offset);
-			btrfs_put_ordered_extent(ordered);
+			bbio->ordered = ordered;
 		}
 
 		/*
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index ba8a61fa3d81fc..004b8f77d14d50 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -2704,8 +2704,11 @@  static int btrfs_extract_ordered_extent(struct btrfs_bio *bbio,
 		return -EINVAL;
 
 	/* No need to split if the ordered extent covers the entire bio. */
-	if (ordered->disk_num_bytes == len)
+	if (ordered->disk_num_bytes == len) {
+		refcount_inc(&ordered->refs);
+		bbio->ordered = ordered;
 		return 0;
+	}
 
 	/*
 	 * Don't split the extent_map for NOCOW extents, as we're writing into
@@ -2722,8 +2725,7 @@  static int btrfs_extract_ordered_extent(struct btrfs_bio *bbio,
 	new = btrfs_split_ordered_extent(ordered, len);
 	if (IS_ERR(new))
 		return PTR_ERR(new);
-	btrfs_put_ordered_extent(new);
-
+	bbio->ordered = new;
 	return 0;
 }