[U-Boot] [PATCH 3/3] ext4: Only write journal entries for modified blocks in unlink_filename

[Lukasz Majewski <l.majewski@samsung.com>]

Hi Stefan,

> Instead of creating a journal entry for each directory block, even
> if the block is unmodified, only log the modified block.
> 
> Signed-off-by: Stefan Br?ns <stefan.bruens@rwth-aachen.de>
> ---
>  fs/ext4/ext4_common.c | 23 +++++++++++++----------
>  1 file changed, 13 insertions(+), 10 deletions(-)
> 
> diff --git a/fs/ext4/ext4_common.c b/fs/ext4/ext4_common.c
> index 11be0b7..ec02eec 100644
> --- a/fs/ext4/ext4_common.c
> +++ b/fs/ext4/ext4_common.c
> @@ -874,8 +874,6 @@ static int unlink_filename(char *filename,
> unsigned int blknr) if (status == 0)
>  		goto fail;
>  
> -	if (ext4fs_log_journal(block_buffer, blknr))
> -		goto fail;
>  	offset = 0;
>  	do {
>  		previous_dir = dir;
> @@ -889,14 +887,6 @@ static int unlink_filename(char *filename,
> unsigned int blknr) if (dir->inode && (strlen(filename) ==
> dir->namelen) && (strncmp(direntname, filename, dir->namelen) == 0)) {
>  			inodeno = le32_to_cpu(dir->inode);
> -			if (previous_dir) {
> -				uint16_t new_len;
> -				new_len =
> le16_to_cpu(previous_dir->direntlen);
> -				new_len +=
> le16_to_cpu(dir->direntlen);
> -				previous_dir->direntlen =
> cpu_to_le16(new_len);
> -			} else {
> -				dir->inode = 0;
> -			}
>  			break;
>  		}
>  
> @@ -905,7 +895,20 @@ static int unlink_filename(char *filename,
> unsigned int blknr) } while (offset < fs->blksz);
>  
>  	if (inodeno > 0) {
> +		printf("file found, deleting\n");
> +		if (ext4fs_log_journal(block_buffer, blknr))
> +			goto fail;
>  
> +		if (previous_dir) {
> +			/* merge dir entry with predecessor */
> +			uint16_t new_len;
> +			new_len =
> le16_to_cpu(previous_dir->direntlen);
> +			new_len += le16_to_cpu(dir->direntlen);
> +			previous_dir->direntlen =
> cpu_to_le16(new_len);
> +		} else {
> +			/* invalidate dir entry */
> +			dir->inode = 0;
> +		}
>  		if (ext4fs_put_metadata(block_buffer, blknr))
>  			goto fail;
>  		ret = inodeno;

Reviewed-by: Lukasz Majewski <l.majewski@samsung.com>

-- 
Best regards,

Lukasz Majewski

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