[XFS] Retry linux inode cacech lookup if we found a stale inode. This

fixes crashes under high nfs load

SGI-PV: 941429
SGI-Modid: xfs-linux:xfs-kern:197929a

Signed-off-by: Christoph Hellwig <hch@sgi.com>
Signed-off-by: Nathan Scott <nathans@sgi.com>

1 files changed, 16 insertions, 12 deletions

diff --git a/fs/xfs/xfs_iget.c b/fs/xfs/xfs_iget.c
index fa796910f3aa..0d9ae8fb4138 100644
--- a/fs/xfs/xfs_iget.c
+++ b/fs/xfs/xfs_iget.c
@@ -30,6 +30,8 @@
  * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
  */
 
+#include <linux/delay.h>
+
 #include "xfs.h"
 
 #include "xfs_macros.h"
@@ -507,14 +509,13 @@ xfs_iget(
 
         XFS_STATS_INC(xs_ig_attempts);
 
+retry:
         if ((inode = iget_locked(XFS_MTOVFS(mp)->vfs_super, ino))) {
                 bhv_desc_t      *bdp;
                 xfs_inode_t     *ip;
-                int             newnode;
 
                 vp = LINVFS_GET_VP(inode);
                 if (inode->i_state & I_NEW) {
-inode_allocate:
                         vn_initialize(inode);
                         error = xfs_iget_core(vp, mp, tp, ino, flags,
                                         lock_flags, ipp, bno);
@@ -525,22 +526,25 @@ inode_allocate:
                                 iput(inode);
                         }
                 } else {
-                        if (is_bad_inode(inode)) {
+                        /*
+                         * If the inode is not fully constructed due to
+                         * filehandle mistmatches wait for the inode to go
+                         * away and try again.
+                         *
+                         * iget_locked will call __wait_on_freeing_inode
+                         * to wait for the inode to go away.
+                         */
+                        if (is_bad_inode(inode) ||
+                            ((bdp = vn_bhv_lookup(VN_BHV_HEAD(vp),
+                                                  &xfs_vnodeops)) == NULL)) {
                                 iput(inode);
-                                return EIO;
+                                delay(1);
+                                goto retry;
                         }
 
-                        bdp = vn_bhv_lookup(VN_BHV_HEAD(vp), &xfs_vnodeops);
-                        if (bdp == NULL) {
-                                XFS_STATS_INC(xs_ig_dup);
-                                goto inode_allocate;
-                        }
                         ip = XFS_BHVTOI(bdp);
                         if (lock_flags != 0)
                                 xfs_ilock(ip, lock_flags);
-                        newnode = (ip->i_d.di_mode == 0);
-                        if (newnode)
-                                xfs_iocore_inode_reinit(ip);
                         XFS_STATS_INC(xs_ig_found);
                         *ipp = ip;
                         error = 0;