Re: [PATCH 10/37] mke2fs: Allow metadata checksums to be turned on at mkfs time

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 2011-08-31, at 6:36 PM, "Darrick J. Wong" <djwong@xxxxxxxxxx> wrote:
> Write out checksummed inodes even when writing out a zeroed table.
> 
> Signed-off-by: Darrick J. Wong <djwong@xxxxxxxxxx>
> ---
> misc/mke2fs.c |   37 ++++++++++++++++++++++++++++++-------
> 1 files changed, 30 insertions(+), 7 deletions(-)
> 
> 
> diff --git a/misc/mke2fs.c b/misc/mke2fs.c
> index 2d57d09..bbc0533 100644
> --- a/misc/mke2fs.c
> +++ b/misc/mke2fs.c
> @@ -309,6 +309,8 @@ static void write_inode_tables(ext2_filsys fs, int lazy_flag, int itable_zeroed)
>    dgrp_t        i;
>    int        num;
>    struct ext2fs_numeric_progress_struct progress;
> +    ext2_ino_t    ino;
> +    struct ext2_inode_large inode;
> 
>    ext2fs_numeric_progress_init(fs, &progress,
>                     _("Writing inode tables: "),
> @@ -330,12 +332,32 @@ static void write_inode_tables(ext2_filsys fs, int lazy_flag, int itable_zeroed)
>            ext2fs_bg_flags_set(fs, i, EXT2_BG_INODE_ZEROED);
>            ext2fs_group_desc_csum_set(fs, i);
>        }
> -        retval = ext2fs_zero_blocks2(fs, blk, num, &blk, &num);
> -        if (retval) {
> -            fprintf(stderr, _("\nCould not write %d "
> -                  "blocks in inode table starting at %llu: %s\n"),
> -                num, blk, error_message(retval));
> -            exit(1);
> +        if (fs->super->s_creator_os == EXT2_OS_LINUX &&
> +            fs->super->s_feature_ro_compat &
> +            EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) {

Somehow it doesn't look like this is skipping the zeroing of the inode table blocks if lazy itable zeroing is set. 

Any measurements on how much this slows down inode table writing (which is already the slowest part of mke2fs)?

> +            bzero(&inode, sizeof(inode));
> +            for (ino = fs->super->s_inodes_per_group * i;
> +                 ino < fs->super->s_inodes_per_group * (i + 1);
> +                 ino++) {

Why recompute "ino" each time through this loop?  It should be enough to simply initialize it at 1 and then increment it for each inode written. 

> +                if (!ino)
> +                    continue;
> +                retval = ext2fs_write_inode(fs, ino, &inode);
> +                if (retval) {
> +                    com_err("inode_init", retval,
> +                        "while writing inode %d\n",
> +                        ino);
> +                    exit(1);
> +                }
> +            }
> +        } else {
> +            retval = ext2fs_zero_blocks2(fs, blk, num, &blk, &num);
> +            if (retval) {
> +                fprintf(stderr, _("\nCould not write %d "
> +                    "blocks in inode table starting "
> +                    "at %llu: %s\n"),
> +                    num, blk, error_message(retval));
> +                exit(1);
> +            }
>        }
>        if (sync_kludge) {
>            if (sync_kludge == 1)
> @@ -829,7 +851,8 @@ static __u32 ok_features[3] = {
>        EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE|
>        EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER|
>        EXT4_FEATURE_RO_COMPAT_GDT_CSUM|
> -        EXT4_FEATURE_RO_COMPAT_BIGALLOC
> +        EXT4_FEATURE_RO_COMPAT_BIGALLOC|
> +        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM
> };
> 
> 
> 
--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html


[Index of Archives]     [Reiser Filesystem Development]     [Ceph FS]     [Kernel Newbies]     [Security]     [Netfilter]     [Bugtraq]     [Linux FS]     [Yosemite National Park]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Samba]     [Device Mapper]     [Linux Media]

  Powered by Linux