cifs: Allow using O_DIRECT with cache=loose

Currently O_DIRECT is supported with cache=none and cache=strict, but
not cache=loose. Add support for using O_DIRECT when mounted with
cache=loose.

Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Signed-off-by: Steve French <smfrench@gmail.com>

diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 53e343d..565a4c0 100644 (file)
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -754,6 +754,9 @@ cifs_loose_read_iter(struct kiocb *iocb, struct iov_iter *iter)
        ssize_t rc;
        struct inode *inode = file_inode(iocb->ki_filp);
 
+       if (iocb->ki_filp->f_flags & O_DIRECT)
+               return cifs_user_readv(iocb, iter);
+
        rc = cifs_revalidate_mapping(inode);
        if (rc)
                return rc;
@@ -768,6 +771,18 @@ static ssize_t cifs_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
        ssize_t written;
        int rc;
 
+       if (iocb->ki_filp->f_flags & O_DIRECT) {
+               written = cifs_user_writev(iocb, from);
+               if (written > 0 && CIFS_CACHE_READ(cinode)) {
+                       cifs_zap_mapping(inode);
+                       cifs_dbg(FYI,
+                                "Set no oplock for inode=%p after a write operation\n",
+                                inode);
+                       cinode->oplock = 0;
+               }
+               return written;
+       }
+
        written = cifs_get_writer(cinode);
        if (written)
                return written;