Merge tag 'nfs-for-3.8-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client updates from Trond Myklebust:
 "Features include:

   - Full audit of BUG_ON asserts in the NFS, SUNRPC and lockd client
     code.  Remove altogether where possible, and replace with
     WARN_ON_ONCE and appropriate error returns where not.
   - NFSv4.1 client adds session dynamic slot table management.  There
     is matching server side code that has been submitted to Bruce for
     consideration.

     Together, this code allows the server to dynamically manage the
     amount of memory it allocates to the duplicate request cache for
     each client.  It will constantly resize those caches to reserve
     more memory for clients that are hot while shrinking caches for
     those that are quiescent.

  In addition, there are assorted bugfixes for the generic NFS write
  code, fixes to deal with the drop_nlink() warnings, and yet another
  fix for NFSv4 getacl."

* tag 'nfs-for-3.8-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (106 commits)
  SUNRPC: continue run over clients list on PipeFS event instead of break
  NFS: Don't use SetPageError in the NFS writeback code
  SUNRPC: variable 'svsk' is unused in function bc_send_request
  SUNRPC: Handle ECONNREFUSED in xs_local_setup_socket
  NFSv4.1: Deal effectively with interrupted RPC calls.
  NFSv4.1: Move the RPC timestamp out of the slot.
  NFSv4.1: Try to deal with NFS4ERR_SEQ_MISORDERED.
  NFS: nfs_lookup_revalidate should not trust an inode with i_nlink == 0
  NFS: Fix calls to drop_nlink()
  NFS: Ensure that we always drop inodes that have been marked as stale
  nfs: Remove unused list nfs4_clientid_list
  nfs: Remove duplicate function declaration in internal.h
  NFS: avoid NULL dereference in nfs_destroy_server
  SUNRPC handle EKEYEXPIRED in call_refreshresult
  SUNRPC set gss gc_expiry to full lifetime
  nfs: fix page dirtying in NFS DIO read codepath
  nfs: don't zero out the rest of the page if we hit the EOF on a DIO READ
  NFSv4.1: Be conservative about the client highest slotid
  NFSv4.1: Handle NFS4ERR_BADSLOT errors correctly
  nfs: don't extend writes to cover entire page if pagecache is invalid
  ...

1 files changed, 14 insertions, 8 deletions

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 1cc71f60b491..32e6c53520e2 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -979,10 +979,11 @@ static int nfs_is_exclusive_create(struct inode *dir, unsigned int flags)
  * particular file and the "nocto" mount flag is not set.
  *
  */
-static inline
+static
 int nfs_lookup_verify_inode(struct inode *inode, unsigned int flags)
 {
 	struct nfs_server *server = NFS_SERVER(inode);
+	int ret;
 
 	if (IS_AUTOMOUNT(inode))
 		return 0;
@@ -993,9 +994,13 @@ int nfs_lookup_verify_inode(struct inode *inode, unsigned int flags)
 	if ((flags & LOOKUP_OPEN) && !(server->flags & NFS_MOUNT_NOCTO) &&
 	    (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)))
 		goto out_force;
-	return 0;
+out:
+	return (inode->i_nlink == 0) ? -ENOENT : 0;
 out_force:
-	return __nfs_revalidate_inode(server, inode);
+	ret = __nfs_revalidate_inode(server, inode);
+	if (ret != 0)
+		return ret;
+	goto out;
 }
 
 /*
@@ -1156,11 +1161,14 @@ static int nfs_dentry_delete(const struct dentry *dentry)
 
 }
 
+/* Ensure that we revalidate inode->i_nlink */
 static void nfs_drop_nlink(struct inode *inode)
 {
 	spin_lock(&inode->i_lock);
-	if (inode->i_nlink > 0)
-		drop_nlink(inode);
+	/* drop the inode if we're reasonably sure this is the last link */
+	if (inode->i_nlink == 1)
+		clear_nlink(inode);
+	NFS_I(inode)->cache_validity |= NFS_INO_INVALID_ATTR;
 	spin_unlock(&inode->i_lock);
 }
 
@@ -1175,8 +1183,8 @@ static void nfs_dentry_iput(struct dentry *dentry, struct inode *inode)
 		NFS_I(inode)->cache_validity |= NFS_INO_INVALID_DATA;
 
 	if (dentry->d_flags & DCACHE_NFSFS_RENAMED) {
-		drop_nlink(inode);
 		nfs_complete_unlink(dentry, inode);
+		nfs_drop_nlink(inode);
 	}
 	iput(inode);
 }
@@ -1647,10 +1655,8 @@ static int nfs_safe_remove(struct dentry *dentry)
 	if (inode != NULL) {
 		NFS_PROTO(inode)->return_delegation(inode);
 		error = NFS_PROTO(dir)->remove(dir, &dentry->d_name);
-		/* The VFS may want to delete this inode */
 		if (error == 0)
 			nfs_drop_nlink(inode);
-		nfs_mark_for_revalidate(inode);
 	} else
 		error = NFS_PROTO(dir)->remove(dir, &dentry->d_name);
 	if (error == -ENOENT)