Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

[linux-2.6-block.git] / kernel / cgroup / cpuset.c

diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index 72afd55f70c64fa936208b5d92db01334965e0a9..4834c4214e9cd15f2122b4747b31a66e5b632df9 100644 (file)
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -39,6 +39,7 @@
 #include <linux/memory.h>
 #include <linux/export.h>
 #include <linux/mount.h>
+#include <linux/fs_context.h>
 #include <linux/namei.h>
 #include <linux/pagemap.h>
 #include <linux/proc_fs.h>
@@ -359,25 +360,52 @@ static inline bool is_in_v2_mode(void)
  * users. If someone tries to mount the "cpuset" filesystem, we
  * silently switch it to mount "cgroup" instead
  */
-static struct dentry *cpuset_mount(struct file_system_type *fs_type,
-                        int flags, const char *unused_dev_name, void *data)
-{
-       struct file_system_type *cgroup_fs = get_fs_type("cgroup");
-       struct dentry *ret = ERR_PTR(-ENODEV);
-       if (cgroup_fs) {
-               char mountopts[] =
-                       "cpuset,noprefix,"
-                       "release_agent=/sbin/cpuset_release_agent";
-               ret = cgroup_fs->mount(cgroup_fs, flags,
-                                          unused_dev_name, mountopts);
-               put_filesystem(cgroup_fs);
+static int cpuset_get_tree(struct fs_context *fc)
+{
+       struct file_system_type *cgroup_fs;
+       struct fs_context *new_fc;
+       int ret;
+
+       cgroup_fs = get_fs_type("cgroup");
+       if (!cgroup_fs)
+               return -ENODEV;
+
+       new_fc = fs_context_for_mount(cgroup_fs, fc->sb_flags);
+       if (IS_ERR(new_fc)) {
+               ret = PTR_ERR(new_fc);
+       } else {
+               static const char agent_path[] = "/sbin/cpuset_release_agent";
+               ret = vfs_parse_fs_string(new_fc, "cpuset", NULL, 0);
+               if (!ret)
+                       ret = vfs_parse_fs_string(new_fc, "noprefix", NULL, 0);
+               if (!ret)
+                       ret = vfs_parse_fs_string(new_fc, "release_agent",
+                                       agent_path, sizeof(agent_path) - 1);
+               if (!ret)
+                       ret = vfs_get_tree(new_fc);
+               if (!ret) {     /* steal the result */
+                       fc->root = new_fc->root;
+                       new_fc->root = NULL;
+               }
+               put_fs_context(new_fc);
        }
+       put_filesystem(cgroup_fs);
        return ret;
 }
 
+static const struct fs_context_operations cpuset_fs_context_ops = {
+       .get_tree       = cpuset_get_tree,
+};
+
+static int cpuset_init_fs_context(struct fs_context *fc)
+{
+       fc->ops = &cpuset_fs_context_ops;
+       return 0;
+}
+
 static struct file_system_type cpuset_fs_type = {
-       .name = "cpuset",
-       .mount = cpuset_mount,
+       .name                   = "cpuset",
+       .init_fs_context        = cpuset_init_fs_context,
 };
 
 /*