On May 26, 2018, at 4:46 PM, Artem Blagodarenko <artem.blagodarenko@xxxxxxxxx> wrote:
>
> e2image and e2fsck automatically try to open some backup superblocks,
> if only blocksize is set or passed superblock can't be opened.
> Try few backup superblocks (e.g. {1, 3, 5, 7, 9} * blocksize * 8).
>
> This code is moved to lib/support/.
I don't recall seeing an explanation of why this is in lib/support/
instead of lib/ext2fs? Maybe as ext2fs_open_backups(), or is there
some reason we don't want to export this function?
> Signed-off-by: Artem Blagodarenko <artem.blagodarenko@xxxxxxxxx>
> ---
>
> diff --git a/e2fsck/message.c b/e2fsck/message.c
> index 727f71d5..415d7609 100644
> --- a/e2fsck/message.c
> +++ b/e2fsck/message.c
> @@ -465,7 +465,8 @@ static _INLINE_ void expand_percent_expression(FILE *f, ext2_filsys fs,
> fprintf(f, "%*lld", width, (long long) ctx->blkcount);
> break;
> case 'S':
> - fprintf(f, "%llu", get_backup_sb(NULL, fs, NULL, NULL));
> + fprintf(f, "%llu", get_first_backup_sb(NULL, NULL, fs,
> + NULL, NULL));
(style) align after '('
> diff --git a/e2fsck/unix.c b/e2fsck/unix.c
> index 491e9eb6..1a5e556f 100644
> --- a/e2fsck/unix.c
> +++ b/e2fsck/unix.c
> @@ -1479,11 +1479,19 @@ restart:
> retval ? _("Superblock invalid,") :
> _("Group descriptors look bad..."));
> orig_superblock = ctx->superblock;
> - get_backup_sb(ctx, fs, ctx->filesystem_name, io_ptr);
> - if (fs)
> - ext2fs_close_free(&fs);
> orig_retval = retval;
> - retval = try_open_fs(ctx, flags, io_ptr, &fs);
> + retval = try_backups(ctx->filesystem_name,
> + ctx->io_options,
> + flags,
> + &ctx->superblock,
> + &ctx->blocksize, io_ptr,
> + &fs);
(style) align after '(', pack onto fewest lines possible
> diff --git a/lib/support/sb_backup.c b/lib/support/sb_backup.c
> new file mode 100644
> index 00000000..5660e237
> --- /dev/null
> +++ b/lib/support/sb_backup.c
(style) remove extra blank lines
> +blk64_t get_first_backup_sb(blk64_t *superblock, unsigned int *block_size,
> + ext2_filsys fs, const char *name,
> + io_manager manager)
(style) align after '('
> +{
> + struct ext2_super_block *sb;
> + io_channel io = NULL;
> + void *buf = NULL;
> + int try_blocksize;
> + blk64_t try_superblock, ret_sb = 8193;
> +
> + /* superblock and block_size can be NULL if fs->super is passed */
> + if (fs && fs->super) {
> + ret_sb = (fs->super->s_blocks_per_group +
> + fs->super->s_first_data_block);
(style) no need for parenthesis here
> + if (superblock)
> + *superblock = ret_sb;
> + if(block_size)
(style) space after "if"
> +}
> +
> +
(style) remove extra blank line
> +errcode_t try_backups(const char *name, const char *io_options,
> + int flags, blk64_t *superblock,
> + unsigned int *block_size, io_manager manager,
> + ext2_filsys *ret_fs)
(style) align after '('
> +{
> + errcode_t retval;
> + blk64_t try_block_number;
> + unsigned int i;
> +
> + /*
> + * Get first superblock location based on heuristic.
> + * Blocksize is also returned and used to find next
> + * superblock copy location.
> + */
> + try_block_number = get_first_backup_sb(superblock, block_size,
> + *ret_fs, name, manager);
(style) align after '('
> +
> +}
> +
> +
(style) remove blank lines at end
> diff --git a/lib/support/sb_backup.h b/lib/support/sb_backup.h
> new file mode 100644
> index 00000000..f1d48bff
> --- /dev/null
> +++ b/lib/support/sb_backup.h
> @@ -0,0 +1,20 @@
> +blk64_t get_first_backup_sb(blk64_t *superblock, unsigned int *block_size,
> + ext2_filsys fs, const char *name,
> + io_manager manager);
> +
> +errcode_t try_backups(const char *name, const char *io_options,
> + int flags, blk64_t *superblock,
> + unsigned int *block_size, io_manager manager,
> + ext2_filsys *ret_fs);
(style) align after '(
> diff --git a/misc/e2image.c b/misc/e2image.c
> index 727e3876..d8569068 100644
> --- a/misc/e2image.c
> +++ b/misc/e2image.c
> @@ -1612,6 +1612,13 @@ int main (int argc, char ** argv)
> sprintf(offset_opt, "offset=%llu", source_offset);
> retval = ext2fs_open2(device_name, offset_opt, open_flag,
> superblock, blocksize, unix_io_manager, &fs);
> + if (retval & (superblock | blocksize)) {
> + printf(_("Try backups in other location.\n"));
> + retval = try_backups(device_name, offset_opt, open_flag,
> + &superblock, &blocksize,
> + unix_io_manager, &fs);
(style) align after '('
Cheers, Andreas
Attachment:
signature.asc
Description: Message signed with OpenPGP
