On 2018/9/3 下午5:46, Nikolay Borisov wrote:
> Instead of returning an error value and using one of the parameters for
> returning the actual object we are interested in just refactor the
> function to directly return btrfs_device *. Also bubble up the error
> handling for the special BTRFS_ERROR_DEV_MISSING_NOT_FOUND value into
> btrfs_rm_device. No functional changes.
>
> Signed-off-by: Nikolay Borisov <nborisov@xxxxxxxx>
Reviewed-by: Qu Wenruo <wqu@xxxxxxxx>
Thanks,
Qu
> ---
> fs/btrfs/dev-replace.c | 8 ++++----
> fs/btrfs/volumes.c | 40 +++++++++++++++++++---------------------
> fs/btrfs/volumes.h | 6 +++---
> 3 files changed, 26 insertions(+), 28 deletions(-)
>
> diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c
> index dec01970d8c5..4e2b67d06305 100644
> --- a/fs/btrfs/dev-replace.c
> +++ b/fs/btrfs/dev-replace.c
> @@ -409,10 +409,10 @@ int btrfs_dev_replace_start(struct btrfs_fs_info *fs_info,
> struct btrfs_device *tgt_device = NULL;
> struct btrfs_device *src_device = NULL;
>
> - ret = btrfs_find_device_by_devspec(fs_info, srcdevid,
> - srcdev_name, &src_device);
> - if (ret)
> - return ret;
> + src_device = btrfs_find_device_by_devspec(fs_info, srcdevid,
> + srcdev_name);
> + if (IS_ERR(src_device))
> + return PTR_ERR(src_device);
>
> ret = btrfs_init_dev_replace_tgtdev(fs_info, tgtdev_name,
> src_device, &tgt_device);
> diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
> index 6202aa15d0d7..ce336b39fa0f 100644
> --- a/fs/btrfs/volumes.c
> +++ b/fs/btrfs/volumes.c
> @@ -1877,10 +1877,16 @@ int btrfs_rm_device(struct btrfs_fs_info *fs_info, const char *device_path,
> if (ret)
> goto out;
>
> - ret = btrfs_find_device_by_devspec(fs_info, devid, device_path,
> - &device);
> - if (ret)
> + device = btrfs_find_device_by_devspec(fs_info, devid, device_path);
> +
> + if (IS_ERR(device)) {
> + if (PTR_ERR(device) == -ENOENT &&
> + strcmp(device_path, "missing") == 0)
> + ret = BTRFS_ERROR_DEV_MISSING_NOT_FOUND;
> + else
> + ret = PTR_ERR(device);
> goto out;
> + }
>
> if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) {
> ret = BTRFS_ERROR_DEV_TGT_REPLACE;
> @@ -2153,30 +2159,22 @@ btrfs_find_device_missing_or_by_path(struct btrfs_fs_info *fs_info,
> /*
> * Lookup a device given by device id, or the path if the id is 0.
> */
> -int btrfs_find_device_by_devspec(struct btrfs_fs_info *fs_info, u64 devid,
> - const char *devpath,
> - struct btrfs_device **device)
> +struct btrfs_device *
> +btrfs_find_device_by_devspec(struct btrfs_fs_info *fs_info, u64 devid,
> + const char *devpath)
> {
> - int ret = 0;
> + struct btrfs_device *device;
>
> if (devid) {
> - *device = btrfs_find_device(fs_info, devid, NULL, NULL);
> - if (!*device)
> - ret = -ENOENT;
> + device = btrfs_find_device(fs_info, devid, NULL, NULL);
> + if (!device)
> + return ERR_PTR(-ENOENT);
> } else {
> if (!devpath || !devpath[0])
> - return -EINVAL;
> -
> - *device = btrfs_find_device_missing_or_by_path(fs_info, devpath);
> - if (IS_ERR(*device)) {
> - if (PTR_ERR(*device) == -ENOENT &&
> - strcmp(devpath, "missing") == 0)
> - ret = BTRFS_ERROR_DEV_MISSING_NOT_FOUND;
> - else
> - ret = PTR_ERR(*device);
> - }
> + return ERR_PTR(-EINVAL);
> + device = btrfs_find_device_missing_or_by_path(fs_info, devpath);
> }
> - return ret;
> + return device;
> }
>
> /*
> diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
> index e7811473024d..aefce895e994 100644
> --- a/fs/btrfs/volumes.h
> +++ b/fs/btrfs/volumes.h
> @@ -410,9 +410,9 @@ int btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
> void btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices, int step);
> void btrfs_assign_next_active_device(struct btrfs_device *device,
> struct btrfs_device *this_dev);
> -int btrfs_find_device_by_devspec(struct btrfs_fs_info *fs_info, u64 devid,
> - const char *devpath,
> - struct btrfs_device **device);
> +struct btrfs_device *btrfs_find_device_by_devspec(struct btrfs_fs_info *fs_info,
> + u64 devid,
> + const char *devpath);
> struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
> const u64 *devid,
> const u8 *uuid);
>
