commit 19f9a63a35cb286318d54827e6c3a36d3e4eea7e
author Darrick J. Wong <darrick.wong@oracle.com> Wed Jan 03 13:42:11 2018 -0600
committer Eric Sandeen <sandeen@redhat.com> Wed Jan 03 13:42:11 2018 -0600
tree 86423e5f5d5d59c3f158fbb25c4a343198b1bc0b
parent 3ee858aa6c10e8705fa309f6c68ec6d0932707fc

xfs: only skip rmap owner checks for unknown-owner rmap removal

Source kernel commit: 68c58e9b9a88c1a9d0c2eaf6c7acefb00f5fbbfb

For rmap removal, refactor the rmap owner checks into a separate
function, then skip the checks if we are performing an unknown-owner
removal.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>

libxfs/xfs_rmap.c

diff --git a/libxfs/xfs_rmap.c b/libxfs/xfs_rmap.c
index 9abc6b1..a6657b8 100644
--- a/libxfs/xfs_rmap.c
+++ b/libxfs/xfs_rmap.c
@@ -366,6 +366,51 @@
 }
 
 /*
+ * Perform all the relevant owner checks for a removal op.  If we're doing an
+ * unknown-owner removal then we have no owner information to check.
+ */
+static int
+xfs_rmap_free_check_owner(
+	struct xfs_mount	*mp,
+	uint64_t		ltoff,
+	struct xfs_rmap_irec	*rec,
+	xfs_fsblock_t		bno,
+	xfs_filblks_t		len,
+	uint64_t		owner,
+	uint64_t		offset,
+	unsigned int		flags)
+{
+	int			error = 0;
+
+	if (owner == XFS_RMAP_OWN_UNKNOWN)
+		return 0;
+
+	/* Make sure the unwritten flag matches. */
+	XFS_WANT_CORRUPTED_GOTO(mp, (flags & XFS_RMAP_UNWRITTEN) ==
+			(rec->rm_flags & XFS_RMAP_UNWRITTEN), out);
+
+	/* Make sure the owner matches what we expect to find in the tree. */
+	XFS_WANT_CORRUPTED_GOTO(mp, owner == rec->rm_owner, out);
+
+	/* Check the offset, if necessary. */
+	if (XFS_RMAP_NON_INODE_OWNER(owner))
+		goto out;
+
+	if (flags & XFS_RMAP_BMBT_BLOCK) {
+		XFS_WANT_CORRUPTED_GOTO(mp, rec->rm_flags & XFS_RMAP_BMBT_BLOCK,
+				out);
+	} else {
+		XFS_WANT_CORRUPTED_GOTO(mp, rec->rm_offset <= offset, out);
+		XFS_WANT_CORRUPTED_GOTO(mp,
+				ltoff + rec->rm_blockcount >= offset + len,
+				out);
+	}
+
+out:
+	return error;
+}
+
+/*
  * Find the extent in the rmap btree and remove it.
  *
  * The record we find should always be an exact match for the extent that we're
@@ -466,33 +511,16 @@
 			goto out_done;
 	}
 
-	/* Make sure the unwritten flag matches. */
-	XFS_WANT_CORRUPTED_GOTO(mp, (flags & XFS_RMAP_UNWRITTEN) ==
-			(ltrec.rm_flags & XFS_RMAP_UNWRITTEN), out_error);
-
 	/* Make sure the extent we found covers the entire freeing range. */
 	XFS_WANT_CORRUPTED_GOTO(mp, ltrec.rm_startblock <= bno &&
-		ltrec.rm_startblock + ltrec.rm_blockcount >=
-		bno + len, out_error);
+			ltrec.rm_startblock + ltrec.rm_blockcount >=
+			bno + len, out_error);
 
-	/* Make sure the owner matches what we expect to find in the tree. */
-	XFS_WANT_CORRUPTED_GOTO(mp, owner == ltrec.rm_owner ||
-				    XFS_RMAP_NON_INODE_OWNER(owner), out_error);
-
-	/* Check the offset, if necessary. */
-	if (!XFS_RMAP_NON_INODE_OWNER(owner)) {
-		if (flags & XFS_RMAP_BMBT_BLOCK) {
-			XFS_WANT_CORRUPTED_GOTO(mp,
-					ltrec.rm_flags & XFS_RMAP_BMBT_BLOCK,
-					out_error);
-		} else {
-			XFS_WANT_CORRUPTED_GOTO(mp,
-					ltrec.rm_offset <= offset, out_error);
-			XFS_WANT_CORRUPTED_GOTO(mp,
-					ltoff + ltrec.rm_blockcount >= offset + len,
-					out_error);
-		}
-	}
+	/* Check owner information. */
+	error = xfs_rmap_free_check_owner(mp, ltoff, &ltrec, bno, len, owner,
+			offset, flags);
+	if (error)
+		goto out_error;
 
 	if (ltrec.rm_startblock == bno && ltrec.rm_blockcount == len) {
 		/* exact match, simply remove the record from rmap tree */