[Patch v4 3/3] CIFS: Add direct I/O functions to file_operations

From: Long Li
Date: Wed Oct 31 2018 - 18:14:39 EST


From: Long Li <longli@xxxxxxxxxxxxx>

With direct read/write functions implemented, add them to file_operations.

Dircet I/O is used under two conditions:
1. When mounting with "cache=none", CIFS uses direct I/O for all user file
data transfer.
2. When opening a file with O_DIRECT, CIFS uses direct I/O for all data
transfer on this file.

Signed-off-by: Long Li <longli@xxxxxxxxxxxxx>
---
fs/cifs/cifsfs.c | 10 ++++------
1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 62f1662..f18091b 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -1113,9 +1113,8 @@ const struct file_operations cifs_file_strict_ops = {
};

const struct file_operations cifs_file_direct_ops = {
- /* BB reevaluate whether they can be done with directio, no cache */
- .read_iter = cifs_user_readv,
- .write_iter = cifs_user_writev,
+ .read_iter = cifs_direct_readv,
+ .write_iter = cifs_direct_writev,
.open = cifs_open,
.release = cifs_close,
.lock = cifs_lock,
@@ -1169,9 +1168,8 @@ const struct file_operations cifs_file_strict_nobrl_ops = {
};

const struct file_operations cifs_file_direct_nobrl_ops = {
- /* BB reevaluate whether they can be done with directio, no cache */
- .read_iter = cifs_user_readv,
- .write_iter = cifs_user_writev,
+ .read_iter = cifs_direct_readv,
+ .write_iter = cifs_direct_writev,
.open = cifs_open,
.release = cifs_close,
.fsync = cifs_fsync,
--
2.7.4