On 2019/10/30 下午8:22, Nikolay Borisov wrote:
> convert is always set to true so there's no point in having it as a
> function parameter or using it as a predicate inside btrfs_alloc_data_chunk.
> Remove it and all relevant code which would have never been executed.
> No semantics changes.
>
> Signed-off-by: Nikolay Borisov <nborisov@xxxxxxxx>
Reviewed-by: Qu Wenruo <wqu@xxxxxxxx>
Just one tip for further patches.
The function btrfs_alloc_data_chunk() is purely used for convert to
create a 1:1 mapped data chunk.
It would be be even better to rename the function to indicate it better.
Thanks,
Qu
> ---
> convert/main.c | 3 +--
> volumes.c | 44 ++++++++++++++------------------------------
> volumes.h | 3 +--
> 3 files changed, 16 insertions(+), 34 deletions(-)
>
> diff --git a/convert/main.c b/convert/main.c
> index 9904deafba45..416ab5d264a3 100644
> --- a/convert/main.c
> +++ b/convert/main.c
> @@ -942,8 +942,7 @@ static int make_convert_data_block_groups(struct btrfs_trans_handle *trans,
>
> len = min(max_chunk_size,
> cache->start + cache->size - cur);
> - ret = btrfs_alloc_data_chunk(trans, fs_info,
> - &cur_backup, len, 1);
> + ret = btrfs_alloc_data_chunk(trans, fs_info, &cur_backup, len);
> if (ret < 0)
> break;
> ret = btrfs_make_block_group(trans, fs_info, 0,
> diff --git a/volumes.c b/volumes.c
> index 87315a884b49..39e824a43736 100644
> --- a/volumes.c
> +++ b/volumes.c
> @@ -1238,14 +1238,11 @@ int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
> /*
> * Alloc a DATA chunk with SINGLE profile.
> *
> - * If 'convert' is set, it will alloc a chunk with 1:1 mapping
> - * (btrfs logical bytenr == on-disk bytenr)
> - * For that case, caller must make sure the chunk and dev_extent are not
> - * occupied.
> + * It allocates a chunk with 1:1 mapping (btrfs logical bytenr == on-disk bytenr)
> + * Caller must make sure the chunk and dev_extent are not occupied.
> */
> int btrfs_alloc_data_chunk(struct btrfs_trans_handle *trans,
> - struct btrfs_fs_info *info, u64 *start,
> - u64 num_bytes, int convert)
> + struct btrfs_fs_info *info, u64 *start, u64 num_bytes)
> {
> u64 dev_offset;
> struct btrfs_root *extent_root = info->extent_root;
> @@ -1264,25 +1261,18 @@ int btrfs_alloc_data_chunk(struct btrfs_trans_handle *trans,
> int stripe_len = BTRFS_STRIPE_LEN;
> struct btrfs_key key;
>
> - key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
> - key.type = BTRFS_CHUNK_ITEM_KEY;
> - if (convert) {
> - if (*start != round_down(*start, info->sectorsize)) {
> - error("DATA chunk start not sectorsize aligned: %llu",
> - (unsigned long long)*start);
> - return -EINVAL;
> - }
> - key.offset = *start;
> - dev_offset = *start;
> - } else {
> - u64 tmp;
>
> - ret = find_next_chunk(info, &tmp);
> - key.offset = tmp;
> - if (ret)
> - return ret;
> + if (*start != round_down(*start, info->sectorsize)) {
> + error("DATA chunk start not sectorsize aligned: %llu",
> + (unsigned long long)*start);
> + return -EINVAL;
> }
>
> + key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
> + key.type = BTRFS_CHUNK_ITEM_KEY;
> + key.offset = *start;
> + dev_offset = *start;
> +
> chunk = kmalloc(btrfs_chunk_item_size(num_stripes), GFP_NOFS);
> if (!chunk)
> return -ENOMEM;
> @@ -1303,12 +1293,8 @@ int btrfs_alloc_data_chunk(struct btrfs_trans_handle *trans,
> while (index < num_stripes) {
> struct btrfs_stripe *stripe;
>
> - if (convert)
> - ret = btrfs_insert_dev_extent(trans, device, key.offset,
> - calc_size, dev_offset);
> - else
> - ret = btrfs_alloc_dev_extent(trans, device, key.offset,
> - calc_size, &dev_offset);
> + ret = btrfs_insert_dev_extent(trans, device, key.offset, calc_size,
> + dev_offset);
> BUG_ON(ret);
>
> device->bytes_used += calc_size;
> @@ -1345,8 +1331,6 @@ int btrfs_alloc_data_chunk(struct btrfs_trans_handle *trans,
> ret = btrfs_insert_item(trans, chunk_root, &key, chunk,
> btrfs_chunk_item_size(num_stripes));
> BUG_ON(ret);
> - if (!convert)
> - *start = key.offset;
>
> map->ce.start = key.offset;
> map->ce.size = num_bytes;
> diff --git a/volumes.h b/volumes.h
> index 83ba827e422b..f6f05054b5c4 100644
> --- a/volumes.h
> +++ b/volumes.h
> @@ -271,8 +271,7 @@ int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
> struct btrfs_fs_info *fs_info, u64 *start,
> u64 *num_bytes, u64 type);
> int btrfs_alloc_data_chunk(struct btrfs_trans_handle *trans,
> - struct btrfs_fs_info *fs_info, u64 *start,
> - u64 num_bytes, int convert);
> + struct btrfs_fs_info *fs_info, u64 *start, u64 num_bytes);
> int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
> int flags);
> int btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
>
