| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <E5C0A205-1123-4D79-86DE-FDAEE106F53C@dilger.ca>
Date: Tue, 26 Sep 2023 14:47:25 -0600
From: Andreas Dilger <adilger@...ger.ca>
To: Li Dongyang <dongyangli@....com>
Cc: Ext4 Developers List <linux-ext4@...r.kernel.org>
Subject: Re: [PATCH 1/2] mke2fs: set free blocks accurately for groups has GDT
On Sep 25, 2023, at 12:08 AM, Li Dongyang <dongyangli@....com> wrote:
>
> This patch is part of the preparation required to allow
> GDT blocks expand beyond a single group,
> it introduces 2 new interfaces:
> - ext2fs_count_used_blocks(), to return the blocks used
> in the bitmap range.
> - ext2fs_reserve_super_and_bgd2() to return blocks used by
> superblock/GDT blocks for every group, by looking up blocks used.
>
> Signed-off-by: Li Dongyang <dongyangli@....com>
Reviewed-by: Andreas Dilger <adilger@...ger.ca>
> ---
> lib/ext2fs/alloc_sb.c | 28 ++++++++++++++++++++++++++--
> lib/ext2fs/ext2fs.h | 6 ++++++
> lib/ext2fs/gen_bitmap64.c | 17 +++++++++++++++--
> lib/ext2fs/initialize.c | 30 ++++++++++++++++++++----------
> misc/mke2fs.c | 2 +-
> 5 files changed, 68 insertions(+), 15 deletions(-)
>
> diff --git a/lib/ext2fs/alloc_sb.c b/lib/ext2fs/alloc_sb.c
> index 8530b40f6..e92739ecc 100644
> --- a/lib/ext2fs/alloc_sb.c
> +++ b/lib/ext2fs/alloc_sb.c
> @@ -46,8 +46,7 @@ int ext2fs_reserve_super_and_bgd(ext2_filsys fs,
> ext2fs_block_bitmap bmap)
> {
> blk64_t super_blk, old_desc_blk, new_desc_blk;
> - blk_t used_blks;
> - int old_desc_blocks, num_blocks;
> + blk_t used_blks, old_desc_blocks, num_blocks;
>
> ext2fs_super_and_bgd_loc2(fs, group, &super_blk,
> &old_desc_blk, &new_desc_blk, &used_blks);
> @@ -79,3 +78,28 @@ int ext2fs_reserve_super_and_bgd(ext2_filsys fs,
>
> return num_blocks ;
> }
> +
> +/*
> + * This function reserves the superblock and block group descriptors
> + * for a given block group and returns the number of blocks used by the
> + * super block and group descriptors by looking up the block bitmap.
> + */
> +errcode_t ext2fs_reserve_super_and_bgd2(ext2_filsys fs,
> + dgrp_t group,
> + ext2fs_block_bitmap bmap,
> + blk_t *desc_blocks)
> +{
> + blk64_t num_blocks;
> + errcode_t retval = 0;
> +
> + ext2fs_reserve_super_and_bgd(fs, group, bmap);
> +
> + retval = ext2fs_count_used_blocks(fs,
> + ext2fs_group_first_block2(fs, group),
> + ext2fs_group_last_block2(fs, group),
> + &num_blocks);
> + if (!retval)
> + *desc_blocks = num_blocks;
> +
> + return retval;
> +}
> diff --git a/lib/ext2fs/ext2fs.h b/lib/ext2fs/ext2fs.h
> index 72c60d2b5..ae79a3443 100644
> --- a/lib/ext2fs/ext2fs.h
> +++ b/lib/ext2fs/ext2fs.h
> @@ -795,6 +795,10 @@ errcode_t ext2fs_alloc_range(ext2_filsys fs, int flags, blk64_t goal,
> extern int ext2fs_reserve_super_and_bgd(ext2_filsys fs,
> dgrp_t group,
> ext2fs_block_bitmap bmap);
> +extern errcode_t ext2fs_reserve_super_and_bgd2(ext2_filsys fs,
> + dgrp_t group,
> + ext2fs_block_bitmap bmap,
> + blk_t *desc_blocks);
> extern void ext2fs_set_block_alloc_stats_callback(ext2_filsys fs,
> void (*func)(ext2_filsys fs,
> blk64_t blk,
> @@ -1483,6 +1487,8 @@ errcode_t ext2fs_convert_subcluster_bitmap(ext2_filsys fs,
> ext2fs_block_bitmap *bitmap);
> errcode_t ext2fs_count_used_clusters(ext2_filsys fs, blk64_t start,
> blk64_t end, blk64_t *out);
> +errcode_t ext2fs_count_used_blocks(ext2_filsys fs, blk64_t start,
> + blk64_t end, blk64_t *out);
>
> /* get_num_dirs.c */
> extern errcode_t ext2fs_get_num_dirs(ext2_filsys fs, ext2_ino_t *ret_num_dirs);
> diff --git a/lib/ext2fs/gen_bitmap64.c b/lib/ext2fs/gen_bitmap64.c
> index 4289e8155..5936dcf53 100644
> --- a/lib/ext2fs/gen_bitmap64.c
> +++ b/lib/ext2fs/gen_bitmap64.c
> @@ -945,8 +945,8 @@ errcode_t ext2fs_find_first_set_generic_bmap(ext2fs_generic_bitmap bitmap,
> return ENOENT;
> }
>
> -errcode_t ext2fs_count_used_clusters(ext2_filsys fs, blk64_t start,
> - blk64_t end, blk64_t *out)
> +errcode_t ext2fs_count_used_blocks(ext2_filsys fs, blk64_t start,
> + blk64_t end, blk64_t *out)
> {
> blk64_t next;
> blk64_t tot_set = 0;
> @@ -975,6 +975,19 @@ errcode_t ext2fs_count_used_clusters(ext2_filsys fs, blk64_t start,
> break;
> }
>
> + if (!retval)
> + *out = tot_set;
> + return retval;
> +}
> +
> +errcode_t ext2fs_count_used_clusters(ext2_filsys fs, blk64_t start,
> + blk64_t end, blk64_t *out)
> +{
> + blk64_t tot_set = 0;
> + errcode_t retval = 0;
> +
> + retval = ext2fs_count_used_blocks(fs, start, end, &tot_set);
> +
> if (!retval)
> *out = EXT2FS_NUM_B2C(fs, tot_set);
> return retval;
> diff --git a/lib/ext2fs/initialize.c b/lib/ext2fs/initialize.c
> index edd692bb9..90012f732 100644
> --- a/lib/ext2fs/initialize.c
> +++ b/lib/ext2fs/initialize.c
> @@ -521,6 +521,15 @@ ipg_retry:
> csum_flag = ext2fs_has_group_desc_csum(fs);
> reserved_inos = super->s_first_ino;
> for (i = 0; i < fs->group_desc_count; i++) {
> + blk_t grp_free_blocks;
> + ext2_ino_t inodes;
> +
> + retval = ext2fs_reserve_super_and_bgd2(fs, i,
> + fs->block_map,
> + &numblocks);
> + if (retval)
> + goto cleanup;
> +
> /*
> * Don't set the BLOCK_UNINIT group for the last group
> * because the block bitmap needs to be padded.
> @@ -530,24 +539,25 @@ ipg_retry:
> ext2fs_bg_flags_set(fs, i,
> EXT2_BG_BLOCK_UNINIT);
> ext2fs_bg_flags_set(fs, i, EXT2_BG_INODE_UNINIT);
> - numblocks = super->s_inodes_per_group;
> + inodes = super->s_inodes_per_group;
> if (reserved_inos) {
> - if (numblocks > reserved_inos) {
> - numblocks -= reserved_inos;
> + if (inodes > reserved_inos) {
> + inodes -= reserved_inos;
> reserved_inos = 0;
> } else {
> - reserved_inos -= numblocks;
> - numblocks = 0;
> + reserved_inos -= inodes;
> + inodes = 0;
> }
> }
> - ext2fs_bg_itable_unused_set(fs, i, numblocks);
> + ext2fs_bg_itable_unused_set(fs, i, inodes);
> }
> - numblocks = ext2fs_reserve_super_and_bgd(fs, i, fs->block_map);
> - if (fs->super->s_log_groups_per_flex)
> +
> + if (!fs->super->s_log_groups_per_flex)
> numblocks += 2 + fs->inode_blocks_per_group;
>
> - free_blocks += numblocks;
> - ext2fs_bg_free_blocks_count_set(fs, i, numblocks);
> + grp_free_blocks = ext2fs_group_blocks_count(fs, i) - numblocks;
> + free_blocks += grp_free_blocks;
> + ext2fs_bg_free_blocks_count_set(fs, i, grp_free_blocks);
> ext2fs_bg_free_inodes_count_set(fs, i, fs->super->s_inodes_per_group);
> ext2fs_bg_used_dirs_count_set(fs, i, 0);
> ext2fs_group_desc_csum_set(fs, i);
> diff --git a/misc/mke2fs.c b/misc/mke2fs.c
> index 4a9c1b092..72c9da12e 100644
> --- a/misc/mke2fs.c
> +++ b/misc/mke2fs.c
> @@ -3522,7 +3522,7 @@ no_journal:
> fs->super->s_mmp_update_interval);
> }
>
> - overhead += fs->super->s_first_data_block;
> + overhead += EXT2FS_NUM_B2C(fs, fs->super->s_first_data_block);
> if (!super_only)
> fs->super->s_overhead_clusters = overhead;
>
> --
> 2.41.0
>
Cheers, Andreas
Download attachment "signature.asc" of type "application/pgp-signature" (874 bytes)
Powered by blists - more mailing lists