[smb3] improve error message when mount options conflict with posix

POSIX extensions require SMB3.1.1 (so improve the error
message when vers=3.0, 2.1 or 2.0 is specified on mount)

Signed-off-by: Steve French <stfrench@microsoft.com>

diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 0b742bd..cff6c01 100644 (file)
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -2340,10 +2340,19 @@ cifs_get_tcon(struct cifs_ses *ses, struct smb3_fs_context *ctx)
                if (ses->server->posix_ext_supported) {
                        tcon->posix_extensions = true;
                        pr_warn_once("SMB3.11 POSIX Extensions are experimental\n");
-               } else {
+               } else if ((ses->server->vals->protocol_id == SMB311_PROT_ID) ||
+                   (strcmp(ses->server->vals->version_string,
+                    SMB3ANY_VERSION_STRING) == 0) ||
+                   (strcmp(ses->server->vals->version_string,
+                    SMBDEFAULT_VERSION_STRING) == 0)) {
                        cifs_dbg(VFS, "Server does not support mounting with posix SMB3.11 extensions\n");
                        rc = -EOPNOTSUPP;
                        goto out_fail;
+               } else {
+                       cifs_dbg(VFS, "Check vers= mount option. SMB3.11 "
+                               "disabled but required for POSIX extensions\n");
+                       rc = -EOPNOTSUPP;
+                       goto out_fail;
                }
        }