Merge tag 'xfs-merge-7.0' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull xfs updates from Carlos Maiolino:
 "This contains several improvements to zoned device support,
  performance improvements for the parent pointers, and a new health
  monitoring feature. There are some improvements in the journaling code
  too but no behavior change expected.

  Last but not least, some code refactoring and bug fixes are also
  included in this series"

* tag 'xfs-merge-7.0' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (67 commits)
  xfs: add sysfs stats for zoned GC
  xfs: give the defer_relog stat a xs_ prefix
  xfs: add zone reset error injection
  xfs: refactor zone reset handling
  xfs: don't mark all discard issued by zoned GC as sync
  xfs: allow setting errortags at mount time
  xfs: use WRITE_ONCE/READ_ONCE for m_errortag
  xfs: move the guts of XFS_ERRORTAG_DELAY out of line
  xfs: don't validate error tags in the I/O path
  xfs: allocate m_errortag early
  xfs: fix the errno sign for the xfs_errortag_{add,clearall} stubs
  xfs: validate log record version against superblock log version
  xfs: fix spacing style issues in xfs_alloc.c
  xfs: remove xfs_zone_gc_space_available
  xfs: use a seprate member to track space availabe in the GC scatch buffer
  xfs: check for deleted cursors when revalidating two btrees
  xfs: fix UAF in xchk_btree_check_block_owner
  xfs: check return value of xchk_scrub_create_subord
  xfs: only call xf{array,blob}_destroy if we have a valid pointer
  xfs: get rid of the xchk_xfile_*_descr calls
  ...

1 files changed, 34 insertions, 0 deletions

diff --git a/block/bio.c b/block/bio.c
index e726c0e280a8..40f690985bfb 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -311,6 +311,40 @@ void bio_reset(struct bio *bio, struct block_device *bdev, blk_opf_t opf)
 }
 EXPORT_SYMBOL(bio_reset);
 
+/**
+ * bio_reuse - reuse a bio with the payload left intact
+ * @bio:	bio to reuse
+ * @opf:	operation and flags for the next I/O
+ *
+ * Allow reusing an existing bio for another operation with all set up
+ * fields including the payload, device and end_io handler left intact.
+ *
+ * Typically used when @bio is first used to read data which is then written
+ * to another location without modification.  @bio must not be in-flight and
+ * owned by the caller.  Can't be used for cloned bios.
+ *
+ * Note: Can't be used when @bio has integrity or blk-crypto contexts for now.
+ * Feel free to add that support when you need it, though.
+ */
+void bio_reuse(struct bio *bio, blk_opf_t opf)
+{
+	unsigned short vcnt = bio->bi_vcnt, i;
+	bio_end_io_t *end_io = bio->bi_end_io;
+	void *private = bio->bi_private;
+
+	WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED));
+	WARN_ON_ONCE(bio_integrity(bio));
+	WARN_ON_ONCE(bio_has_crypt_ctx(bio));
+
+	bio_reset(bio, bio->bi_bdev, opf);
+	for (i = 0; i < vcnt; i++)
+		bio->bi_iter.bi_size += bio->bi_io_vec[i].bv_len;
+	bio->bi_vcnt = vcnt;
+	bio->bi_private = private;
+	bio->bi_end_io = end_io;
+}
+EXPORT_SYMBOL_GPL(bio_reuse);
+
 static struct bio *__bio_chain_endio(struct bio *bio)
 {
 	struct bio *parent = bio->bi_private;