[PATCH] btrfs: use min_size variable to setup block rsv in btrfs_replace_file_extents()

[PATCH] btrfs: use min_size variable to setup block rsv in btrfs_replace_file_extents()

[fdmanana]

From: Filipe Manana <fdmanana@suse.com>

There's no need to calculate again the size for the temporary block
reserve in btrfs_replace_file_extents() - we have already calculated it
and stored it in the 'min_size' variable.

So use the variable to make it more clear and also make the variable const
since it's not supposed to change during the whole function.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
---
 fs/btrfs/file.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index f007f1f2fd84..7aab4a98caaa 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -2395,7 +2395,7 @@ int btrfs_replace_file_extents(struct btrfs_inode *inode,
 	struct btrfs_drop_extents_args drop_args = { 0 };
 	struct btrfs_root *root = inode->root;
 	struct btrfs_fs_info *fs_info = root->fs_info;
-	u64 min_size = btrfs_calc_insert_metadata_size(fs_info, 1);
+	const u64 min_size = btrfs_calc_insert_metadata_size(fs_info, 1);
 	u64 ino_size = round_up(inode->vfs_inode.i_size, fs_info->sectorsize);
 	struct btrfs_trans_handle *trans = NULL;
 	struct btrfs_block_rsv rsv;
@@ -2408,7 +2408,7 @@ int btrfs_replace_file_extents(struct btrfs_inode *inode,
 		return -EINVAL;
 
 	btrfs_init_metadata_block_rsv(fs_info, &rsv, BTRFS_BLOCK_RSV_TEMP);
-	rsv.size = btrfs_calc_insert_metadata_size(fs_info, 1);
+	rsv.size = min_size;
 	rsv.failfast = true;
 
 	/*
-- 
2.47.2

Re: [PATCH] btrfs: use min_size variable to setup block rsv in btrfs_replace_file_extents()

[Qu Wenruo]

在 2026/4/20 23:23, fdmanana@kernel.org 写道:
> From: Filipe Manana <fdmanana@suse.com>
> 
> There's no need to calculate again the size for the temporary block
> reserve in btrfs_replace_file_extents() - we have already calculated it
> and stored it in the 'min_size' variable.
> 
> So use the variable to make it more clear and also make the variable const
> since it's not supposed to change during the whole function.
> 
> Signed-off-by: Filipe Manana <fdmanana@suse.com>

Reviewed-by: Qu Wenruo <wqu@suse.com>

Thanks,
Qu

> ---
>   fs/btrfs/file.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
> index f007f1f2fd84..7aab4a98caaa 100644
> --- a/fs/btrfs/file.c
> +++ b/fs/btrfs/file.c
> @@ -2395,7 +2395,7 @@ int btrfs_replace_file_extents(struct btrfs_inode *inode,
>   	struct btrfs_drop_extents_args drop_args = { 0 };
>   	struct btrfs_root *root = inode->root;
>   	struct btrfs_fs_info *fs_info = root->fs_info;
> -	u64 min_size = btrfs_calc_insert_metadata_size(fs_info, 1);
> +	const u64 min_size = btrfs_calc_insert_metadata_size(fs_info, 1);
>   	u64 ino_size = round_up(inode->vfs_inode.i_size, fs_info->sectorsize);
>   	struct btrfs_trans_handle *trans = NULL;
>   	struct btrfs_block_rsv rsv;
> @@ -2408,7 +2408,7 @@ int btrfs_replace_file_extents(struct btrfs_inode *inode,
>   		return -EINVAL;
>   
>   	btrfs_init_metadata_block_rsv(fs_info, &rsv, BTRFS_BLOCK_RSV_TEMP);
> -	rsv.size = btrfs_calc_insert_metadata_size(fs_info, 1);
> +	rsv.size = min_size;
>   	rsv.failfast = true;
>   
>   	/*

Re: [PATCH] btrfs: use min_size variable to setup block rsv in btrfs_replace_file_extents()

[David Sterba]

On Mon, Apr 20, 2026 at 02:53:56PM +0100, fdmanana@kernel.org wrote:
> From: Filipe Manana <fdmanana@suse.com>
> 
> There's no need to calculate again the size for the temporary block
> reserve in btrfs_replace_file_extents() - we have already calculated it
> and stored it in the 'min_size' variable.
> 
> So use the variable to make it more clear and also make the variable const
> since it's not supposed to change during the whole function.
> 
> Signed-off-by: Filipe Manana <fdmanana@suse.com>

Reviewed-by: David Sterba <dsterba@suse.com>