[PATCH v4 02/27] xfs: Increase XFS_DEFER_OPS_NR_INODES to 5

[allison.henderson@xxxxxxxxxx]

From: Allison Henderson <allison.henderson@xxxxxxxxxx>

Renames that generate parent pointer updates can join up to 5
inodes locked in sorted order.  So we need to increase the
number of defer ops inodes and relock them in the same way.

Signed-off-by: Allison Henderson <allison.henderson@xxxxxxxxxx>
Reviewed-by: Darrick J. Wong <djwong@xxxxxxxxxx>
---
 fs/xfs/libxfs/xfs_defer.c | 28 ++++++++++++++++++++++++++--
 fs/xfs/libxfs/xfs_defer.h |  8 +++++++-
 fs/xfs/xfs_inode.c        |  2 +-
 fs/xfs/xfs_inode.h        |  1 +
 4 files changed, 35 insertions(+), 4 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_defer.c b/fs/xfs/libxfs/xfs_defer.c
index 5a321b783398..c0279b57e51d 100644
--- a/fs/xfs/libxfs/xfs_defer.c
+++ b/fs/xfs/libxfs/xfs_defer.c
@@ -820,13 +820,37 @@ xfs_defer_ops_continue(
 	struct xfs_trans		*tp,
 	struct xfs_defer_resources	*dres)
 {
-	unsigned int			i;
+	unsigned int			i, j;
+	struct xfs_inode		*sips[XFS_DEFER_OPS_NR_INODES];
+	struct xfs_inode		*temp;
 
 	ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
 	ASSERT(!(tp->t_flags & XFS_TRANS_DIRTY));
 
 	/* Lock the captured resources to the new transaction. */
-	if (dfc->dfc_held.dr_inos == 2)
+	if (dfc->dfc_held.dr_inos > 2) {
+		/*
+		 * Renames with parent pointer updates can lock up to 5 inodes,
+		 * sorted by their inode number.  So we need to make sure they
+		 * are relocked in the same way.
+		 */
+		memset(sips, 0, sizeof(sips));
+		for (i = 0; i < dfc->dfc_held.dr_inos; i++)
+			sips[i] = dfc->dfc_held.dr_ip[i];
+
+		/* Bubble sort of at most 5 inodes */
+		for (i = 0; i < dfc->dfc_held.dr_inos; i++) {
+			for (j = 1; j < dfc->dfc_held.dr_inos; j++) {
+				if (sips[j]->i_ino < sips[j-1]->i_ino) {
+					temp = sips[j];
+					sips[j] = sips[j-1];
+					sips[j-1] = temp;
+				}
+			}
+		}
+
+		xfs_lock_inodes(sips, dfc->dfc_held.dr_inos, XFS_ILOCK_EXCL);
+	} else if (dfc->dfc_held.dr_inos == 2)
 		xfs_lock_two_inodes(dfc->dfc_held.dr_ip[0], XFS_ILOCK_EXCL,
 				    dfc->dfc_held.dr_ip[1], XFS_ILOCK_EXCL);
 	else if (dfc->dfc_held.dr_inos == 1)
diff --git a/fs/xfs/libxfs/xfs_defer.h b/fs/xfs/libxfs/xfs_defer.h
index 114a3a4930a3..fdf6941f8f4d 100644
--- a/fs/xfs/libxfs/xfs_defer.h
+++ b/fs/xfs/libxfs/xfs_defer.h
@@ -70,7 +70,13 @@ extern const struct xfs_defer_op_type xfs_attr_defer_type;
 /*
  * Deferred operation item relogging limits.
  */
-#define XFS_DEFER_OPS_NR_INODES	2	/* join up to two inodes */
+
+/*
+ * Rename w/ parent pointers can require up to 5 inodes with deferred ops to
+ * be joined to the transaction: src_dp, target_dp, src_ip, target_ip, and wip.
+ * These inodes are locked in sorted order by their inode numbers
+ */
+#define XFS_DEFER_OPS_NR_INODES	5
 #define XFS_DEFER_OPS_NR_BUFS	2	/* join up to two buffers */
 
 /* Resources that must be held across a transaction roll. */
diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index c000b74dd203..5ebbfceb1ada 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -447,7 +447,7 @@ xfs_lock_inumorder(
  * lock more than one at a time, lockdep will report false positives saying we
  * have violated locking orders.
  */
-static void
+void
 xfs_lock_inodes(
 	struct xfs_inode	**ips,
 	int			inodes,
diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h
index fa780f08dc89..2eaed98af814 100644
--- a/fs/xfs/xfs_inode.h
+++ b/fs/xfs/xfs_inode.h
@@ -574,5 +574,6 @@ void xfs_end_io(struct work_struct *work);
 
 int xfs_ilock2_io_mmap(struct xfs_inode *ip1, struct xfs_inode *ip2);
 void xfs_iunlock2_io_mmap(struct xfs_inode *ip1, struct xfs_inode *ip2);
+void xfs_lock_inodes(struct xfs_inode **ips, int inodes, uint lock_mode);
 
 #endif	/* __XFS_INODE_H__ */
-- 
2.25.1