Re: [PATCH] btrfs: use correct type for sectorsize/nodesize/blocksize

On Wed, Jun 24, 2026 at 01:42:42PM +0930, Qu Wenruo wrote:
> Btrfs' nodesize and sectorsize are all u32 values, there is no need to
> use u64 for local usage.
> 
> Furthermore some call sites also use "blocksize" or "bs" for sectorsize,
> also change them to use the minimal type u32 instead.
> 
> Since we're here, also reorder those local variables so that they won't
> cause extra holes for stack memory, and consitify the
> sectorsize/nodesize/blocksize/bs usage.
> 

Reviewed-by: Boris Burkov <[email protected]>

> Signed-off-by: Qu Wenruo <[email protected]>
> ---
>  fs/btrfs/disk-io.c | 12 ++++++------
>  fs/btrfs/fiemap.c  |  4 ++--
>  fs/btrfs/file.c    |  4 ++--
>  fs/btrfs/inode.c   |  4 ++--
>  fs/btrfs/reflink.c |  8 ++++----
>  fs/btrfs/send.c    |  2 +-
>  6 files changed, 17 insertions(+), 17 deletions(-)
> 
> diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
> index 0a7d80da9c94..fa5922a21e51 100644
> --- a/fs/btrfs/disk-io.c
> +++ b/fs/btrfs/disk-io.c
> @@ -2390,8 +2390,8 @@ static int validate_sys_chunk_array(const struct btrfs_fs_info *fs_info,
>  int btrfs_validate_super(const struct btrfs_fs_info *fs_info,
>  			 const struct btrfs_super_block *sb, int mirror_num)
>  {
> -	u64 nodesize = btrfs_super_nodesize(sb);
> -	u64 sectorsize = btrfs_super_sectorsize(sb);
> +	const u32 nodesize = btrfs_super_nodesize(sb);
> +	const u32 sectorsize = btrfs_super_sectorsize(sb);
>  	int ret = 0;
>  	const bool ignore_flags = btrfs_test_opt(fs_info, IGNORESUPERFLAGS);
>  
> @@ -2433,24 +2433,24 @@ int btrfs_validate_super(const struct btrfs_fs_info *fs_info,
>  	 */
>  	if (unlikely(!is_power_of_2(sectorsize) || sectorsize < BTRFS_MIN_BLOCKSIZE ||
>  		     sectorsize > BTRFS_MAX_METADATA_BLOCKSIZE)) {
> -		btrfs_err(fs_info, "invalid sectorsize %llu", sectorsize);
> +		btrfs_err(fs_info, "invalid sectorsize %u", sectorsize);
>  		ret = -EINVAL;
>  	}
>  
>  	if (unlikely(!btrfs_supported_blocksize(sectorsize))) {
>  		btrfs_err(fs_info,
> -			"sectorsize %llu not yet supported for page size %lu",
> +			"sectorsize %u not yet supported for page size %lu",
>  			sectorsize, PAGE_SIZE);
>  		ret = -EINVAL;
>  	}
>  
>  	if (unlikely(!is_power_of_2(nodesize) || nodesize < sectorsize ||
>  		     nodesize > BTRFS_MAX_METADATA_BLOCKSIZE)) {
> -		btrfs_err(fs_info, "invalid nodesize %llu", nodesize);
> +		btrfs_err(fs_info, "invalid nodesize %u", nodesize);
>  		ret = -EINVAL;
>  	}
>  	if (unlikely(nodesize != le32_to_cpu(sb->__unused_leafsize))) {
> -		btrfs_err(fs_info, "invalid leafsize %u, should be %llu",
> +		btrfs_err(fs_info, "invalid leafsize %u, should be %u",
>  			  le32_to_cpu(sb->__unused_leafsize), nodesize);
>  		ret = -EINVAL;
>  	}
> diff --git a/fs/btrfs/fiemap.c b/fs/btrfs/fiemap.c
> index 6263e837093e..1da1ccea5b03 100644
> --- a/fs/btrfs/fiemap.c
> +++ b/fs/btrfs/fiemap.c
> @@ -641,9 +641,9 @@ static int extent_fiemap(struct btrfs_inode *inode,
>  	u64 prev_extent_end;
>  	u64 range_start;
>  	u64 range_end;
> -	const u64 sectorsize = inode->root->fs_info->sectorsize;
> -	bool stopped = false;
> +	const u32 sectorsize = inode->root->fs_info->sectorsize;
>  	int ret;
> +	bool stopped = false;
>  
>  	cache.entries_size = PAGE_SIZE / sizeof(struct btrfs_fiemap_entry);
>  	cache.entries = kmalloc_objs(struct btrfs_fiemap_entry,
> diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
> index a2a2df2df786..df8f6f565070 100644
> --- a/fs/btrfs/file.c
> +++ b/fs/btrfs/file.c
> @@ -2888,8 +2888,8 @@ enum {
>  static int btrfs_zero_range_check_range_boundary(struct btrfs_inode *inode,
>  						 u64 offset)
>  {
> -	const u64 sectorsize = inode->root->fs_info->sectorsize;
>  	struct extent_map *em;
> +	const u32 sectorsize = inode->root->fs_info->sectorsize;
>  	int ret;
>  
>  	offset = round_down(offset, sectorsize);
> @@ -2916,9 +2916,9 @@ static int btrfs_zero_range(struct inode *inode,
>  	struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
>  	struct extent_map *em;
>  	struct extent_changeset *data_reserved = NULL;
> +	const u32 sectorsize = fs_info->sectorsize;
>  	int ret;
>  	u64 alloc_hint = 0;
> -	const u64 sectorsize = fs_info->sectorsize;
>  	const u64 orig_start = offset;
>  	const u64 orig_end = offset + len - 1;
>  	u64 alloc_start = round_down(offset, sectorsize);
> diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
> index ebd1387fcc76..ea772ec788f9 100644
> --- a/fs/btrfs/inode.c
> +++ b/fs/btrfs/inode.c
> @@ -860,11 +860,11 @@ static void compress_file_range(struct btrfs_work *work)
>  	struct btrfs_inode *inode = async_chunk->inode;
>  	struct btrfs_fs_info *fs_info = inode->root->fs_info;
>  	struct compressed_bio *cb = NULL;
> -	u64 blocksize = fs_info->sectorsize;
>  	u64 start = async_chunk->start;
>  	u64 end = async_chunk->end;
>  	u64 actual_end;
>  	u64 i_size;
> +	const u32 blocksize = fs_info->sectorsize;
>  	u32 cur_len;
>  	int ret = 0;
>  	unsigned long total_compressed = 0;
> @@ -2865,7 +2865,6 @@ static int insert_reserved_file_extent(struct btrfs_trans_handle *trans,
>  				       u64 qgroup_reserved)
>  {
>  	struct btrfs_root *root = inode->root;
> -	const u64 sectorsize = root->fs_info->sectorsize;
>  	BTRFS_PATH_AUTO_FREE(path);
>  	struct extent_buffer *leaf;
>  	struct btrfs_key ins;
> @@ -2875,6 +2874,7 @@ static int insert_reserved_file_extent(struct btrfs_trans_handle *trans,
>  	u64 num_bytes = btrfs_stack_file_extent_num_bytes(stack_fi);
>  	u64 ram_bytes = btrfs_stack_file_extent_ram_bytes(stack_fi);
>  	struct btrfs_drop_extents_args drop_args = { 0 };
> +	const u32 sectorsize = root->fs_info->sectorsize;
>  	int ret;
>  
>  	path = btrfs_alloc_path();
> diff --git a/fs/btrfs/reflink.c b/fs/btrfs/reflink.c
> index 9a49d2ecb949..5205b508127c 100644
> --- a/fs/btrfs/reflink.c
> +++ b/fs/btrfs/reflink.c
> @@ -691,7 +691,7 @@ static int btrfs_extent_same_range(struct btrfs_inode *src, u64 loff, u64 len,
>  	const u64 end = dst_loff + len - 1;
>  	struct extent_state *cached_state = NULL;
>  	struct btrfs_fs_info *fs_info = src->root->fs_info;
> -	const u64 bs = fs_info->sectorsize;
> +	const u32 bs = fs_info->sectorsize;
>  	int ret;
>  
>  	/*
> @@ -760,10 +760,10 @@ static noinline int btrfs_clone_files(struct file *file, struct file *file_src,
>  	struct inode *inode = file_inode(file);
>  	struct inode *src = file_inode(file_src);
>  	struct btrfs_fs_info *fs_info = inode_to_fs_info(inode);
> -	int ret;
>  	u64 len = olen;
> -	u64 bs = fs_info->sectorsize;
>  	u64 end;
> +	const u32 bs = fs_info->sectorsize;
> +	int ret;
>  
>  	/*
>  	 * VFS's generic_remap_file_range_prep() protects us from cloning the
> @@ -841,8 +841,8 @@ static int btrfs_remap_file_range_prep(struct file *file_in, loff_t pos_in,
>  {
>  	struct btrfs_inode *inode_in = BTRFS_I(file_inode(file_in));
>  	struct btrfs_inode *inode_out = BTRFS_I(file_inode(file_out));
> -	u64 bs = inode_out->root->fs_info->sectorsize;
>  	u64 wb_len;
> +	const u32 bs = inode_out->root->fs_info->sectorsize;
>  	int ret;
>  
>  	if (!(remap_flags & REMAP_FILE_DEDUP)) {
> diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c
> index d664e470fd77..48a6667053d8 100644
> --- a/fs/btrfs/send.c
> +++ b/fs/btrfs/send.c
> @@ -6038,9 +6038,9 @@ static int send_write_or_clone(struct send_ctx *sctx,
>  			       struct clone_root *clone_root)
>  {
>  	int ret = 0;
> +	const u32 bs = sctx->send_root->fs_info->sectorsize;
>  	u64 offset = key->offset;
>  	u64 end;
> -	u64 bs = sctx->send_root->fs_info->sectorsize;
>  	struct btrfs_file_extent_item *ei;
>  	u64 disk_byte;
>  	u64 data_offset;
> -- 
> 2.54.0
>