From 898feaf6dca5a9d304de252860d214a6ae96a998 Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@infradead.org>
Date: Sun, 18 Dec 2011 20:00:10 +0000
Subject: [PATCH] --- yaml --- r: 286039 b: refs/heads/master c:
 f392e6319a4e9a028b0c8b48f000bb01d660ad53 h: refs/heads/master i:   286037:
 4caffeb5244470544c4ac6e8f4cef928c3324ad8   286035:
 9e89ac250091b3125db3d59fbc2342e2a5e67060   286031:
 097ac2f51325c2e1ce4fce9b21b73ba139f0b2b2 v: v3

---
 [refs]                        |  2 +-
 trunk/fs/xfs/xfs_inode.c      | 27 +++++++++++++++++++++------
 trunk/fs/xfs/xfs_inode.h      |  3 ++-
 trunk/fs/xfs/xfs_inode_item.c |  2 +-
 trunk/fs/xfs/xfs_super.c      |  1 -
 5 files changed, 25 insertions(+), 10 deletions(-)

diff --git a/[refs] b/[refs]
index 415531d4c0bd..2a1bc171c46b 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 474fce067521a40dbacc722e8ba119e81c2d31bf
+refs/heads/master: f392e6319a4e9a028b0c8b48f000bb01d660ad53
diff --git a/trunk/fs/xfs/xfs_inode.c b/trunk/fs/xfs/xfs_inode.c
index eeb60d31b086..62603369b523 100644
--- a/trunk/fs/xfs/xfs_inode.c
+++ b/trunk/fs/xfs/xfs_inode.c
@@ -2037,7 +2037,7 @@ xfs_idestroy_fork(
  * once someone is waiting for it to be unpinned.
  */
 static void
-xfs_iunpin_nowait(
+xfs_iunpin(
 	struct xfs_inode	*ip)
 {
 	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
@@ -2049,14 +2049,29 @@ xfs_iunpin_nowait(
 
 }
 
+static void
+__xfs_iunpin_wait(
+	struct xfs_inode	*ip)
+{
+	wait_queue_head_t *wq = bit_waitqueue(&ip->i_flags, __XFS_IPINNED_BIT);
+	DEFINE_WAIT_BIT(wait, &ip->i_flags, __XFS_IPINNED_BIT);
+
+	xfs_iunpin(ip);
+
+	do {
+		prepare_to_wait(wq, &wait.wait, TASK_UNINTERRUPTIBLE);
+		if (xfs_ipincount(ip))
+			io_schedule();
+	} while (xfs_ipincount(ip));
+	finish_wait(wq, &wait.wait);
+}
+
 void
 xfs_iunpin_wait(
 	struct xfs_inode	*ip)
 {
-	if (xfs_ipincount(ip)) {
-		xfs_iunpin_nowait(ip);
-		wait_event(ip->i_ipin_wait, (xfs_ipincount(ip) == 0));
-	}
+	if (xfs_ipincount(ip))
+		__xfs_iunpin_wait(ip);
 }
 
 /*
@@ -2415,7 +2430,7 @@ xfs_iflush(
 	 * out for us if they occur after the log force completes.
 	 */
 	if (!(flags & SYNC_WAIT) && xfs_ipincount(ip)) {
-		xfs_iunpin_nowait(ip);
+		xfs_iunpin(ip);
 		xfs_ifunlock(ip);
 		return EAGAIN;
 	}
diff --git a/trunk/fs/xfs/xfs_inode.h b/trunk/fs/xfs/xfs_inode.h
index 960d2a89b3ac..4acbe740be46 100644
--- a/trunk/fs/xfs/xfs_inode.h
+++ b/trunk/fs/xfs/xfs_inode.h
@@ -238,7 +238,6 @@ typedef struct xfs_inode {
 	mrlock_t		i_lock;		/* inode lock */
 	mrlock_t		i_iolock;	/* inode IO lock */
 	atomic_t		i_pincount;	/* inode pin count */
-	wait_queue_head_t	i_ipin_wait;	/* inode pinning wait queue */
 	spinlock_t		i_flags_lock;	/* inode i_flags lock */
 	/* Miscellaneous state. */
 	unsigned long		i_flags;	/* see defined flags below */
@@ -367,6 +366,8 @@ xfs_set_projid(struct xfs_inode *ip,
 #define XFS_IDIRTY_RELEASE	(1 << 6) /* dirty release already seen */
 #define __XFS_IFLOCK_BIT	7	 /* inode is being flushed right now */
 #define XFS_IFLOCK		(1 << __XFS_IFLOCK_BIT)
+#define __XFS_IPINNED_BIT	8	 /* wakeup key for zero pin count */
+#define XFS_IPINNED		(1 << __XFS_IPINNED_BIT)
 
 /*
  * Per-lifetime flags need to be reset when re-using a reclaimable inode during
diff --git a/trunk/fs/xfs/xfs_inode_item.c b/trunk/fs/xfs/xfs_inode_item.c
index c8d4ce0efd5a..91d71dcd4852 100644
--- a/trunk/fs/xfs/xfs_inode_item.c
+++ b/trunk/fs/xfs/xfs_inode_item.c
@@ -555,7 +555,7 @@ xfs_inode_item_unpin(
 	trace_xfs_inode_unpin(ip, _RET_IP_);
 	ASSERT(atomic_read(&ip->i_pincount) > 0);
 	if (atomic_dec_and_test(&ip->i_pincount))
-		wake_up(&ip->i_ipin_wait);
+		wake_up_bit(&ip->i_flags, __XFS_IPINNED_BIT);
 }
 
 /*
diff --git a/trunk/fs/xfs/xfs_super.c b/trunk/fs/xfs/xfs_super.c
index 6851fa7b1afa..ee5b695c99a7 100644
--- a/trunk/fs/xfs/xfs_super.c
+++ b/trunk/fs/xfs/xfs_super.c
@@ -828,7 +828,6 @@ xfs_fs_inode_init_once(
 	/* xfs inode */
 	atomic_set(&ip->i_pincount, 0);
 	spin_lock_init(&ip->i_flags_lock);
-	init_waitqueue_head(&ip->i_ipin_wait);
 
 	mrlock_init(&ip->i_lock, MRLOCK_ALLOW_EQUAL_PRI|MRLOCK_BARRIER,
 		     "xfsino", ip->i_ino);