On Thu, Sep 05, 2019 at 02:01:10PM +0300, Artem Blagodarenko wrote:
> tune2fs is used to make e2label duties. ext2fs_open2() reads group
> descriptors which are not used during disk label obtaining, but takes
> a lot of time on large partitions.
>
> This patch adds ext2fs_read_sb(), there only initialized superblock
> is returned This saves time dramatically.
>
> Signed-off-by: Artem Blagodarenko <c17828@xxxxxxxx>
> Cray-bug-id: LUS-5777
> ---
> lib/ext2fs/ext2fs.h | 2 ++
> lib/ext2fs/openfs.c | 16 ++++++++++++++++
> misc/tune2fs.c | 23 +++++++++++++++--------
> 3 files changed, 33 insertions(+), 8 deletions(-)
>
> diff --git a/lib/ext2fs/ext2fs.h b/lib/ext2fs/ext2fs.h
> index 59fd9742..3a63b74d 100644
> --- a/lib/ext2fs/ext2fs.h
> +++ b/lib/ext2fs/ext2fs.h
> @@ -1630,6 +1630,8 @@ extern int ext2fs_journal_sb_start(int blocksize);
> extern errcode_t ext2fs_open(const char *name, int flags, int superblock,
> unsigned int block_size, io_manager manager,
> ext2_filsys *ret_fs);
> +extern errcode_t ext2fs_read_sb(const char *name, io_manager manager,
> + struct ext2_super_block * super);
> extern errcode_t ext2fs_open2(const char *name, const char *io_options,
> int flags, int superblock,
> unsigned int block_size, io_manager manager,
> diff --git a/lib/ext2fs/openfs.c b/lib/ext2fs/openfs.c
> index 51b54a44..95f45d84 100644
> --- a/lib/ext2fs/openfs.c
> +++ b/lib/ext2fs/openfs.c
> @@ -99,6 +99,22 @@ static void block_sha_map_free_entry(void *data)
> return;
> }
>
> +errcode_t ext2fs_read_sb(const char *name, io_manager manager,
> + struct ext2_super_block * super)
> +{
> + io_channel io;
> + errcode_t retval = 0;
> +
> + retval = manager->open(name, 0, &io);
> + if (!retval) {
> + retval = io_channel_read_blk(io, 1, -SUPERBLOCK_SIZE,
> + super);
> + io_channel_close(io);
> + }
> +
> + return retval;
> +}
> +
> /*
> * Note: if superblock is non-zero, block-size must also be non-zero.
> * Superblock and block_size can be zero to use the default size.
> diff --git a/misc/tune2fs.c b/misc/tune2fs.c
> index 7d2d38d7..fea607e1 100644
> --- a/misc/tune2fs.c
> +++ b/misc/tune2fs.c
> @@ -2879,6 +2879,21 @@ int tune2fs_main(int argc, char **argv)
> #endif
> io_ptr = unix_io_manager;
>
> + if (print_label) {
> + /* For e2label emulation */
> + struct ext2_super_block sb;
> +
> + /* Read only superblock. Nothing else metters.*/
matters. */
> + retval = ext2fs_read_sb(device_name, io_ptr, &sb);
> + if (!retval) {
> + printf("%.*s\n", (int) sizeof(sb.s_volume_name),
> + sb.s_volume_name);
> + }
Um, does this drop the error without making a report?
> +
> + remove_error_table(&et_ext2_error_table);
> + return retval;
> + }
I wonder if ext[24] should implement FS_IOC_[GS]ETFSLABEL for mounted
filesystems ... ?
--D
> +
> retry_open:
> if ((open_flag & EXT2_FLAG_RW) == 0 || f_flag)
> open_flag |= EXT2_FLAG_SKIP_MMP;
> @@ -2972,14 +2987,6 @@ retry_open:
> sb = fs->super;
> fs->flags &= ~EXT2_FLAG_MASTER_SB_ONLY;
>
> - if (print_label) {
> - /* For e2label emulation */
> - printf("%.*s\n", (int) sizeof(sb->s_volume_name),
> - sb->s_volume_name);
> - remove_error_table(&et_ext2_error_table);
> - goto closefs;
> - }
> -
> retval = ext2fs_check_if_mounted(device_name, &mount_flags);
> if (retval) {
> com_err("ext2fs_check_if_mount", retval,
> --
> 2.14.3
>
