CIFS: Respect O_SYNC and O_DIRECT flags during reconnect
Currently the client translates O_SYNC and O_DIRECT flags
into corresponding SMB create options when openning a file.
The problem is that on reconnect when the file is being
re-opened the client doesn't set those flags and it causes
a server to reject re-open requests because create options
don't match. The latter means that any subsequent system
call against that open file fail until a share is re-mounted.
Fix this by properly setting SMB create options when
re-openning files after reconnects.
Fixes: 1013e760d10e6: ("SMB3: Don't ignore O_SYNC/O_DSYNC and O_DIRECT flags")
Cc: Stable <stable@vger.kernel.org>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 67e7d0f..7713177 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -728,6 +728,13 @@ cifs_reopen_file(struct cifsFileInfo *cfile, bool can_flush)
if (backup_cred(cifs_sb))
create_options |= CREATE_OPEN_BACKUP_INTENT;
+ /* O_SYNC also has bit for O_DSYNC so following check picks up either */
+ if (cfile->f_flags & O_SYNC)
+ create_options |= CREATE_WRITE_THROUGH;
+
+ if (cfile->f_flags & O_DIRECT)
+ create_options |= CREATE_NO_BUFFER;
+
if (server->ops->get_lease_key)
server->ops->get_lease_key(inode, &cfile->fid);