NFS: Optimise away unnecessary setattrs for open(O_TRUNC);
Currently, we will correctly optimise away a truncate that doesn't
change the file size. However, in the case of open(O_TRUNC), we
also want to optimise away the time changes.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 577ad5a..65486e6 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -402,7 +402,7 @@
goto out;
}
-#define NFS_VALID_ATTRS (ATTR_MODE|ATTR_UID|ATTR_GID|ATTR_SIZE|ATTR_ATIME|ATTR_ATIME_SET|ATTR_MTIME|ATTR_MTIME_SET|ATTR_FILE)
+#define NFS_VALID_ATTRS (ATTR_MODE|ATTR_UID|ATTR_GID|ATTR_SIZE|ATTR_ATIME|ATTR_ATIME_SET|ATTR_MTIME|ATTR_MTIME_SET|ATTR_FILE|ATTR_OPEN)
int
nfs_setattr(struct dentry *dentry, struct iattr *attr)
@@ -424,7 +424,7 @@
/* Optimization: if the end result is no change, don't RPC */
attr->ia_valid &= NFS_VALID_ATTRS;
- if ((attr->ia_valid & ~ATTR_FILE) == 0)
+ if ((attr->ia_valid & ~(ATTR_FILE|ATTR_OPEN)) == 0)
return 0;
/* Write all dirty data */