From: Jeff Layton <jlayton@redhat.com>
Date: Mon, 28 Jun 2010 12:36:01 -0400
Subject: [fs] nfs: clean up inode handling functions
Message-id: <1277728562-28052-4-git-send-email-jlayton@redhat.com>
Patchwork-id: 26584
O-Subject: [RHEL5.6 PATCH 3/4] BZ#601800: NFS: Clean up nfs_refresh_inode() and
	nfs_post_op_update_inode()
Bugzilla: 601800
RH-Acked-by: Steve Dickson <SteveD@redhat.com>

From: Trond Myklebust <Trond.Myklebust@netapp.com>

Try to avoid taking and dropping the inode->i_lock more than once. Do so by
moving the code in nfs_refresh_inode() that needs to be done under the
spinlock into a function nfs_refresh_inode_locked(), and then having both
nfs_refresh_inode() and nfs_post_op_update_inode() call it directly.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>

diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 0090188..a2662c4 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -852,6 +852,15 @@ static int nfs_check_inode_attributes(struct inode *inode, struct nfs_fattr *fat
 	return 0;
 }
 
+static int nfs_refresh_inode_locked(struct inode *inode, struct nfs_fattr *fattr)
+{
+	struct nfs_inode *nfsi = NFS_I(inode);
+
+	if (time_after(fattr->time_start, nfsi->last_updated))
+		return nfs_update_inode(inode, fattr);
+	return nfs_check_inode_attributes(inode, fattr);
+}
+
 /**
  * nfs_refresh_inode - try to update the inode attribute cache
  * @inode - pointer to inode
@@ -864,17 +873,12 @@ static int nfs_check_inode_attributes(struct inode *inode, struct nfs_fattr *fat
  */
 int nfs_refresh_inode(struct inode *inode, struct nfs_fattr *fattr)
 {
-	struct nfs_inode *nfsi = NFS_I(inode);
 	int status;
 
 	if ((fattr->valid & NFS_ATTR_FATTR) == 0)
 		return 0;
 	spin_lock(&inode->i_lock);
-	if (time_after(fattr->time_start, nfsi->last_updated))
-		status = nfs_update_inode(inode, fattr);
-	else
-		status = nfs_check_inode_attributes(inode, fattr);
-
+	status = nfs_refresh_inode_locked(inode, fattr);
 	spin_unlock(&inode->i_lock);
 	return status;
 }
@@ -890,13 +894,16 @@ int nfs_refresh_inode(struct inode *inode, struct nfs_fattr *fattr)
 int nfs_post_op_update_inode(struct inode *inode, struct nfs_fattr *fattr)
 {
 	struct nfs_inode *nfsi = NFS_I(inode);
+	int status = 0;
 
 	spin_lock(&inode->i_lock);
 	nfsi->cache_validity |= NFS_INO_INVALID_ATTR|NFS_INO_REVAL_PAGECACHE;
 	if (S_ISDIR(inode->i_mode))
 		nfsi->cache_validity |= NFS_INO_INVALID_DATA;
+	if ((fattr->valid & NFS_ATTR_FATTR) != 0)
+		status = nfs_refresh_inode_locked(inode, fattr);
 	spin_unlock(&inode->i_lock);
-	return nfs_refresh_inode(inode, fattr);
+	return status;
 }
 
 /**