+static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
+{
+ struct btrfs_root *root = fdentry(file)->d_sb->s_fs_info;
+ struct btrfs_fs_info *fs_info = root->fs_info;
+ struct btrfs_device *device;
+ struct request_queue *q;
+ struct fstrim_range range;
+ u64 minlen = ULLONG_MAX;
+ u64 num_devices = 0;
+ int ret;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ mutex_lock(&fs_info->fs_devices->device_list_mutex);
+ list_for_each_entry(device, &fs_info->fs_devices->devices, dev_list) {
+ if (!device->bdev)
+ continue;
+ q = bdev_get_queue(device->bdev);
+ if (blk_queue_discard(q)) {
+ num_devices++;
+ minlen = min((u64)q->limits.discard_granularity,
+ minlen);
+ }
+ }
+ mutex_unlock(&fs_info->fs_devices->device_list_mutex);
+ if (!num_devices)
+ return -EOPNOTSUPP;
+
+ if (copy_from_user(&range, arg, sizeof(range)))
+ return -EFAULT;
+
+ range.minlen = max(range.minlen, minlen);
+ ret = btrfs_trim_fs(root, &range);
+ if (ret < 0)
+ return ret;
+
+ if (copy_to_user(arg, &range, sizeof(range)))
+ return -EFAULT;
+
+ return 0;
+}
+