NFS: Do not aggressively cache file attributes in the case of O_DIRECT

A file that is open for O_DIRECT is by definition not obeying
close-to-open cache consistency semantics, so let's not cache
the attributes too aggressively either.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

1 files changed, 5 insertions, 0 deletions

diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index 159b64ede82a..01dccf18da0a 100644
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -419,6 +419,11 @@ extern void nfs_end_io_write(struct inode *inode);
 extern void nfs_start_io_direct(struct inode *inode);
 extern void nfs_end_io_direct(struct inode *inode);
 
+static inline bool nfs_file_io_is_buffered(struct nfs_inode *nfsi)
+{
+        return test_bit(NFS_INO_ODIRECT, &nfsi->flags) == 0;
+}
+
 /* namespace.c */
 #define NFS_PATH_CANONICAL 1
 extern char *nfs_path(char **p, struct dentry *dentry,