fs: add FSCONFIG_CMD_CREATE_EXCL

[linux-block.git] / fs / fsopen.c

diff --git a/fs/fsopen.c b/fs/fsopen.c
index a69b7c9cc59c631995289fc8174929771285763b..ce03f6521c8870fb31127dc85be0cdeff370074b 100644 (file)
--- a/fs/fsopen.c
+++ b/fs/fsopen.c
@@ -209,7 +209,7 @@ err:
        return ret;
 }
 
-static int vfs_cmd_create(struct fs_context *fc)
+static int vfs_cmd_create(struct fs_context *fc, bool exclusive)
 {
        struct super_block *sb;
        int ret;
@@ -220,7 +220,12 @@ static int vfs_cmd_create(struct fs_context *fc)
        if (!mount_capable(fc))
                return -EPERM;
 
+       /* require the new mount api */
+       if (exclusive && fc->ops == &legacy_fs_context_ops)
+               return -EOPNOTSUPP;
+
        fc->phase = FS_CONTEXT_CREATING;
+       fc->exclusive = exclusive;
 
        ret = vfs_get_tree(fc);
        if (ret) {
@@ -284,7 +289,9 @@ static int vfs_fsconfig_locked(struct fs_context *fc, int cmd,
                return ret;
        switch (cmd) {
        case FSCONFIG_CMD_CREATE:
-               return vfs_cmd_create(fc);
+               return vfs_cmd_create(fc, false);
+       case FSCONFIG_CMD_CREATE_EXCL:
+               return vfs_cmd_create(fc, true);
        case FSCONFIG_CMD_RECONFIGURE:
                return vfs_cmd_reconfigure(fc);
        default:
@@ -381,6 +388,7 @@ SYSCALL_DEFINE5(fsconfig,
                        return -EINVAL;
                break;
        case FSCONFIG_CMD_CREATE:
+       case FSCONFIG_CMD_CREATE_EXCL:
        case FSCONFIG_CMD_RECONFIGURE:
                if (_key || _value || aux)
                        return -EINVAL;