[Ocfs2-tools-devel] [PATCH 1/3] fsck.ocfs2: Move to JBD2 header and structures.

[Tao Ma]

Joel Becker wrote:
> Change all defines and structures to JBD2 structures.  This is backwards
> compatible with the JBD journals, and is capable of handling even the
> oldest ocfs2 filesystems.
> 
> The only major functional change is to use journal_tag_size() instead of
> sizeof(journal_block_tag_t) when walking the descriptor block.
> fsck.ocfs2 and debugfs.ocfs2 are updated.
> 
> Signed-off-by: Joel Becker <joel.becker at oracle.com>

> @@ -71,6 +71,7 @@ static void scan_journal(FILE *out, char *buf, int len,
>  errcode_t read_journal(ocfs2_filesys *fs, uint64_t blkno, FILE *out)
>  {
>  	char *buf = NULL;
> +	char *jsb_buf = NULL;
>  	char *p;
>  	uint64_t blocknum;
>  	uint64_t len;
> @@ -81,6 +82,7 @@ errcode_t read_journal(ocfs2_filesys *fs, uint64_t blkno, FILE *out)
>  	int buflenbits;
>  	ocfs2_cached_inode *ci = NULL;
>  	errcode_t ret;
> +	journal_superblock_t *jsb;
>  
>  	ret = ocfs2_read_cached_inode(fs, blkno, &ci);
>  	if (ret) {
> @@ -88,6 +90,13 @@ errcode_t read_journal(ocfs2_filesys *fs, uint64_t blkno, FILE *out)
>  		goto bail;
>  	}
>  
> +	ret = ocfs2_malloc_block(fs->fs_io, &jsb_buf);
> +	if (ret) {
> +		com_err(gbls.cmd, ret,
> +			"while allocating journal superblock buffer");
> +		goto bail;
> +	}
> +
>  	buflenbits = buflen >>
>  			OCFS2_RAW_SB(gbls.fs->fs_super)->s_blocksize_bits;
>  	ret = ocfs2_malloc_blocks(fs->fs_io, buflenbits, &buf);
> @@ -98,6 +107,7 @@ errcode_t read_journal(ocfs2_filesys *fs, uint64_t blkno, FILE *out)
>  
>  	offset = 0;
>  	blocknum = 0;
> +	jsb = (journal_superblock_t *)jsb_buf;
>  	while (1) {
>  		ret = ocfs2_file_read(ci, buf, buflen, offset, &got);
>  		if (ret) {
> @@ -112,13 +122,15 @@ errcode_t read_journal(ocfs2_filesys *fs, uint64_t blkno, FILE *out)
>  		len = got;
>  
>  		if (offset == 0) {
> -			dump_jbd_superblock(out, (journal_superblock_t *)buf);
> +			dump_jbd_superblock(out, jsb);
> +			memcpy(jsb_buf, buf, fs->fs_blocksize);
> +			ocfs2_swap_journal_superblock(jsb);
you set jsb as jsb_buf above, but read the block in buf. So jsb will be 
used uninitialized? You may need to move "memcpy" above the 
dump_jbd_superblock if I read your code correctly.
>  			blocknum++;
>  			p += fs->fs_blocksize;
>  			len -= fs->fs_blocksize;
>  		}
>  
> -		scan_journal(out, p, len, &blocknum, &last_unknown);
> +		scan_journal(out, jsb, p, len, &blocknum, &last_unknown);
>  
>  		if (got < buflen)
>  			break;
> @@ -131,6 +143,8 @@ errcode_t read_journal(ocfs2_filesys *fs, uint64_t blkno, FILE *out)
>  	}
>  
>  bail:
> +	if (jsb_buf)
> +		ocfs2_free(&jsb_buf);
>  	if (buf)
>  		ocfs2_free(&buf);
>  	if (ci)

Regards,
Tao