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

Lukasz Majewski
2016-10-14T10:31:44Z

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

Samsung R&D Institute Poland (SRPOL) | Linux Platform Group