Btrfs: Refactor btrfs_ioctl_snap_create()

Split it into two functions for two different ioctls, since they
share no common code.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index f87552a..02554e1 100644 (file)
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -946,58 +946,54 @@ out:
 }
 
 static noinline int btrfs_ioctl_snap_create(struct file *file,
-                                           void __user *arg, int subvol,
-                                           int v2)
+                                           void __user *arg, int subvol)
 {
-       struct btrfs_ioctl_vol_args *vol_args = NULL;
-       struct btrfs_ioctl_vol_args_v2 *vol_args_v2 = NULL;
-       char *name;
-       u64 fd;
+       struct btrfs_ioctl_vol_args *vol_args;
        int ret;
 
-       if (v2) {
-               u64 transid = 0;
-               u64 *ptr = NULL;
+       vol_args = memdup_user(arg, sizeof(*vol_args));
+       if (IS_ERR(vol_args))
+               return PTR_ERR(vol_args);
+       vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
 
-               vol_args_v2 = memdup_user(arg, sizeof(*vol_args_v2));
-               if (IS_ERR(vol_args_v2))
-                       return PTR_ERR(vol_args_v2);
+       ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
+                                             vol_args->fd, subvol, NULL);
 
-               if (vol_args_v2->flags & ~BTRFS_SUBVOL_CREATE_ASYNC) {
-                       ret = -EINVAL;
-                       goto out;
-               }
-
-               name = vol_args_v2->name;
-               fd = vol_args_v2->fd;
-               vol_args_v2->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
+       kfree(vol_args);
+       return ret;
+}
 
-               if (vol_args_v2->flags & BTRFS_SUBVOL_CREATE_ASYNC)
-                       ptr = &transid;
+static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
+                                              void __user *arg, int subvol)
+{
+       struct btrfs_ioctl_vol_args_v2 *vol_args;
+       int ret;
+       u64 transid = 0;
+       u64 *ptr = NULL;
 
-               ret = btrfs_ioctl_snap_create_transid(file, name, fd,
-                                                     subvol, ptr);
+       vol_args = memdup_user(arg, sizeof(*vol_args));
+       if (IS_ERR(vol_args))
+               return PTR_ERR(vol_args);
+       vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
 
-               if (ret == 0 && ptr &&
-                   copy_to_user(arg +
-                                offsetof(struct btrfs_ioctl_vol_args_v2,
-                                         transid), ptr, sizeof(*ptr)))
-                       ret = -EFAULT;
-       } else {
-               vol_args = memdup_user(arg, sizeof(*vol_args));
-               if (IS_ERR(vol_args))
-                       return PTR_ERR(vol_args);
-               name = vol_args->name;
-               fd = vol_args->fd;
-               vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
-
-               ret = btrfs_ioctl_snap_create_transid(file, name, fd,
-                                                     subvol, NULL);
+       if (vol_args->flags & ~BTRFS_SUBVOL_CREATE_ASYNC) {
+               ret = -EINVAL;
+               goto out;
        }
+
+       if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
+               ptr = &transid;
+
+       ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
+                                             vol_args->fd, subvol, ptr);
+
+       if (ret == 0 && ptr &&
+           copy_to_user(arg +
+                        offsetof(struct btrfs_ioctl_vol_args_v2,
+                                 transid), ptr, sizeof(*ptr)))
+               ret = -EFAULT;
 out:
        kfree(vol_args);
-       kfree(vol_args_v2);
-
        return ret;
 }
 
@@ -2257,11 +2253,11 @@ long btrfs_ioctl(struct file *file, unsigned int
        case FS_IOC_GETVERSION:
                return btrfs_ioctl_getversion(file, argp);
        case BTRFS_IOC_SNAP_CREATE:
-               return btrfs_ioctl_snap_create(file, argp, 0, 0);
+               return btrfs_ioctl_snap_create(file, argp, 0);
        case BTRFS_IOC_SNAP_CREATE_V2:
-               return btrfs_ioctl_snap_create(file, argp, 0, 1);
+               return btrfs_ioctl_snap_create_v2(file, argp, 0);
        case BTRFS_IOC_SUBVOL_CREATE:
-               return btrfs_ioctl_snap_create(file, argp, 1, 0);
+               return btrfs_ioctl_snap_create(file, argp, 1);
        case BTRFS_IOC_SNAP_DESTROY:
                return btrfs_ioctl_snap_destroy(file, argp);
        case BTRFS_IOC_DEFAULT_SUBVOL: