Merge git://oss.sgi.com:8090/xfs/xfs-2.6

* git://oss.sgi.com:8090/xfs/xfs-2.6:
  [XFS] Remove KERNEL_VERSION macros from xfs_dmapi.h
  [XFS] Prevent a deadlock when xfslogd unpins inodes.
  [XFS] Clean up i_flags and i_flags_lock handling.
  [XFS] 956664: dm_read_invis() changes i_atime
  [XFS] rename uio_read() to xfs_uio_read()
  [XFS] Keep lockdep happy.
  [XFS] 956618: Linux crashes on boot with XFS-DMAPI filesystem when

1 files changed, 27 insertions, 37 deletions

diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index c27d7d49..d72c80d 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -2193,7 +2193,7 @@ xfs_ifree_cluster(
 			/* Inode not in memory or we found it already,
 			 * nothing to do
 			 */
-			if (!ip || (ip->i_flags & XFS_ISTALE)) {
+			if (!ip || xfs_iflags_test(ip, XFS_ISTALE)) {
 				read_unlock(&ih->ih_lock);
 				continue;
 			}
@@ -2215,10 +2215,7 @@ xfs_ifree_cluster(
 
 			if (ip == free_ip) {
 				if (xfs_iflock_nowait(ip)) {
-					spin_lock(&ip->i_flags_lock);
-					ip->i_flags |= XFS_ISTALE;
-					spin_unlock(&ip->i_flags_lock);
-
+					xfs_iflags_set(ip, XFS_ISTALE);
 					if (xfs_inode_clean(ip)) {
 						xfs_ifunlock(ip);
 					} else {
@@ -2231,9 +2228,7 @@ xfs_ifree_cluster(
 
 			if (xfs_ilock_nowait(ip, XFS_ILOCK_EXCL)) {
 				if (xfs_iflock_nowait(ip)) {
-					spin_lock(&ip->i_flags_lock);
-					ip->i_flags |= XFS_ISTALE;
-					spin_unlock(&ip->i_flags_lock);
+					xfs_iflags_set(ip, XFS_ISTALE);
 
 					if (xfs_inode_clean(ip)) {
 						xfs_ifunlock(ip);
@@ -2263,9 +2258,7 @@ xfs_ifree_cluster(
 				AIL_LOCK(mp,s);
 				iip->ili_flush_lsn = iip->ili_item.li_lsn;
 				AIL_UNLOCK(mp, s);
-				spin_lock(&iip->ili_inode->i_flags_lock);
-				iip->ili_inode->i_flags |= XFS_ISTALE;
-				spin_unlock(&iip->ili_inode->i_flags_lock);
+				xfs_iflags_set(ip, XFS_ISTALE);
 				pre_flushed++;
 			}
 			lip = lip->li_bio_list;
@@ -2748,42 +2741,39 @@ xfs_iunpin(
 {
 	ASSERT(atomic_read(&ip->i_pincount) > 0);
 
-	if (atomic_dec_and_test(&ip->i_pincount)) {
+	if (atomic_dec_and_lock(&ip->i_pincount, &ip->i_flags_lock)) {
+
 		/*
-		 * If the inode is currently being reclaimed, the
-		 * linux inode _and_ the xfs vnode may have been
-		 * freed so we cannot reference either of them safely.
-		 * Hence we should not try to do anything to them
-		 * if the xfs inode is currently in the reclaim
-		 * path.
+		 * If the inode is currently being reclaimed, the link between
+		 * the bhv_vnode and the xfs_inode will be broken after the
+		 * XFS_IRECLAIM* flag is set. Hence, if these flags are not
+		 * set, then we can move forward and mark the linux inode dirty
+		 * knowing that it is still valid as it won't freed until after
+		 * the bhv_vnode<->xfs_inode link is broken in xfs_reclaim. The
+		 * i_flags_lock is used to synchronise the setting of the
+		 * XFS_IRECLAIM* flags and the breaking of the link, and so we
+		 * can execute atomically w.r.t to reclaim by holding this lock
+		 * here.
 		 *
-		 * However, we still need to issue the unpin wakeup
-		 * call as the inode reclaim may be blocked waiting for
-		 * the inode to become unpinned.
+		 * However, we still need to issue the unpin wakeup call as the
+		 * inode reclaim may be blocked waiting for the inode to become
+		 * unpinned.
 		 */
-		struct inode *inode = NULL;
 
-		spin_lock(&ip->i_flags_lock);
-		if (!(ip->i_flags & (XFS_IRECLAIM|XFS_IRECLAIMABLE))) {
+		if (!__xfs_iflags_test(ip, XFS_IRECLAIM|XFS_IRECLAIMABLE)) {
 			bhv_vnode_t	*vp = XFS_ITOV_NULL(ip);
+			struct inode *inode = NULL;
+
+			BUG_ON(vp == NULL);
+			inode = vn_to_inode(vp);
+			BUG_ON(inode->i_state & I_CLEAR);
 
 			/* make sync come back and flush this inode */
-			if (vp) {
-				inode = vn_to_inode(vp);
-
-				if (!(inode->i_state &
-						(I_NEW|I_FREEING|I_CLEAR))) {
-					inode = igrab(inode);
-					if (inode)
-						mark_inode_dirty_sync(inode);
-				} else
-					inode = NULL;
-			}
+			if (!(inode->i_state & (I_NEW|I_FREEING)))
+				mark_inode_dirty_sync(inode);
 		}
 		spin_unlock(&ip->i_flags_lock);
 		wake_up(&ip->i_ipin_wait);
-		if (inode)
-			iput(inode);
 	}
 }