4.16-stable review patch. If anyone has any objections, please let me know.
------------------
From: Steve French <smfrench@xxxxxxxxx>
commit 6e70c267e68d77679534dcf4aaf84e66f2cf1425 upstream.
As with NFS, which ignores sync on directory handles,
fsync on a directory handle is a noop for CIFS/SMB3.
Do not return an error on it. It breaks some database
apps otherwise.
Signed-off-by: Steve French <smfrench@xxxxxxxxx>
CC: Stable <stable@xxxxxxxxxxxxxxx>
Reviewed-by: Ronnie Sahlberg <lsahlber@xxxxxxxxxx>
Reviewed-by: Pavel Shilovsky <pshilov@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/cifs/cifsfs.c | 13 +++++++++++++
1 file changed, 13 insertions(+)
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -1047,6 +1047,18 @@ out:
return rc;
}
+/*
+ * Directory operations under CIFS/SMB2/SMB3 are synchronous, so fsync()
+ * is a dummy operation.
+ */
+static int cifs_dir_fsync(struct file *file, loff_t start, loff_t end, int datasync)
+{
+ cifs_dbg(FYI, "Sync directory - name: %pD datasync: 0x%x\n",
+ file, datasync);
+
+ return 0;
+}
+
static ssize_t cifs_copy_file_range(struct file *src_file, loff_t off,
struct file *dst_file, loff_t destoff,
size_t len, unsigned int flags)
@@ -1181,6 +1193,7 @@ const struct file_operations cifs_dir_op
.copy_file_range = cifs_copy_file_range,
.clone_file_range = cifs_clone_file_range,
.llseek = generic_file_llseek,
+ .fsync = cifs_dir_fsync,
};
static void
