NFS: Make stat() return updated mtimes after a write()

 The SuS states that a call to write() will cause mtime to be updated on
 the file. In order to satisfy that requirement, we need to flush out
 any cached writes in nfs_getattr().
 Speed things up slightly by not committing the writes.

 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

3 files changed, 15 insertions, 11 deletions

diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index acde2c5725bf..2c7f8aac1dec 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -952,6 +952,8 @@ int nfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
         int need_atime = NFS_I(inode)->cache_validity & NFS_INO_INVALID_ATIME;
         int err;
 
+        /* Flush out writes to the server in order to update c/mtime */
+        nfs_sync_inode(inode, 0, 0, FLUSH_WAIT|FLUSH_NOCOMMIT);
         if (__IS_FLG(inode, MS_NOATIME))
                 need_atime = 0;
         else if (__IS_FLG(inode, MS_NODIRATIME) && S_ISDIR(inode->i_mode))
diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 1ce0c200df16..9449b6835509 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -1377,22 +1377,23 @@ int nfs_commit_inode(struct inode *inode, int how)
 int nfs_sync_inode(struct inode *inode, unsigned long idx_start,
                   unsigned int npages, int how)
 {
-        int     error,
-                wait;
+        int nocommit = how & FLUSH_NOCOMMIT;
+        int wait = how & FLUSH_WAIT;
+        int error;
 
-        wait = how & FLUSH_WAIT;
-        how &= ~FLUSH_WAIT;
+        how &= ~(FLUSH_WAIT|FLUSH_NOCOMMIT);
 
         do {
-                error = 0;
-                if (wait)
+                if (wait) {
                         error = nfs_wait_on_requests(inode, idx_start, npages);
-                if (error == 0)
-                        error = nfs_flush_inode(inode, idx_start, npages, how);
-#if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
-                if (error == 0)
+                        if (error != 0)
+                                continue;
+                }
+                error = nfs_flush_inode(inode, idx_start, npages, how);
+                if (error != 0)
+                        continue;
+                if (!nocommit)
                         error = nfs_commit_inode(inode, how);
-#endif
         } while (error > 0);
         return error;
 }
diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h
index d38010ba6477..408d82d3d97c 100644
--- a/include/linux/nfs_fs.h
+++ b/include/linux/nfs_fs.h
@@ -62,6 +62,7 @@
 #define FLUSH_STABLE            4       /* commit to stable storage */
 #define FLUSH_LOWPRI            8       /* low priority background flush */
 #define FLUSH_HIGHPRI           16      /* high priority memory reclaim flush */
+#define FLUSH_NOCOMMIT          32      /* Don't send the NFSv3/v4 COMMIT */
 
 #ifdef __KERNEL__