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>

1 files changed, 40 insertions, 44 deletions

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index f87552a1d7ea..02554e19d974 100644
--- 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: