Re: [PATCH 1/3] e2fsck: update quota when optimizing the extent tree

["Darrick J. Wong" <darrick.wong@oracle.com>]

On Sat, Apr 15, 2017 at 09:41:16AM -0400, Theodore Ts'o wrote:
> If quota is enabled, optimizing the extent tree wouldn't update the
> in-memory quota statistics, so that a subsequent e2fsck run would show
> that the quota usage statistics on disk were incorrect.
> 
> Google-Bug-Id: 36391645
> 
> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
> ---
>  e2fsck/e2fsck.c  |  1 +
>  e2fsck/e2fsck.h  |  1 +
>  e2fsck/extents.c | 23 ++++++++++++++++++-----
>  e2fsck/pass1.c   |  1 +
>  4 files changed, 21 insertions(+), 5 deletions(-)
> 
> diff --git a/e2fsck/e2fsck.c b/e2fsck/e2fsck.c
> index 0f9da46a..4baedbac 100644
> --- a/e2fsck/e2fsck.c
> +++ b/e2fsck/e2fsck.c
> @@ -169,6 +169,7 @@ errcode_t e2fsck_reset_context(e2fsck_t ctx)
>  	ctx->fs_fragmented = 0;
>  	ctx->fs_fragmented_dir = 0;
>  	ctx->large_files = 0;
> +	ctx->clusters_allocated = 0;
>  
>  	for (i=0; i < MAX_EXTENT_DEPTH_COUNT; i++)
>  		ctx->extent_depth_count[i] = 0;
> diff --git a/e2fsck/e2fsck.h b/e2fsck/e2fsck.h
> index f3568106..ecd3b1e1 100644
> --- a/e2fsck/e2fsck.h
> +++ b/e2fsck/e2fsck.h
> @@ -372,6 +372,7 @@ struct e2fsck_struct {
>  	profile_t	profile;
>  	int blocks_per_page;
>  	ext2_u32_list encrypted_dirs;
> +	__u32 clusters_allocated;
>  
>  	/* Reserve blocks for root and l+f re-creation */
>  	blk64_t root_repair_block, lnf_repair_block;
> diff --git a/e2fsck/extents.c b/e2fsck/extents.c
> index c4167e16..1df31d71 100644
> --- a/e2fsck/extents.c
> +++ b/e2fsck/extents.c
> @@ -208,17 +208,21 @@ static int find_blocks(ext2_filsys fs, blk64_t *blocknr, e2_blkcnt_t blockcnt,
>  static errcode_t rebuild_extent_tree(e2fsck_t ctx, struct extent_list *list,
>  				     ext2_ino_t ino)
>  {
> -	struct ext2_inode	inode;
> +	struct ext2_inode_large	inode;
> +	struct ext2_inode	*inode_ptr;
>  	errcode_t		retval;
>  	ext2_extent_handle_t	handle;
>  	unsigned int		i, ext_written;
>  	struct ext2fs_extent	*ex, extent;
> +	__u32			start_val;
>  
>  	list->count = 0;
>  	list->blocks_freed = 0;
>  	list->ino = ino;
>  	list->ext_read = 0;
> -	e2fsck_read_inode(ctx, ino, &inode, "rebuild_extents");
> +	inode_ptr = (struct ext2_inode *) &inode;
> +	e2fsck_read_inode_full(ctx, ino, inode_ptr, sizeof(inode),
> +			       "rebuild_extents");
>  
>  	/* Skip deleted inodes and inline data files */
>  	if (inode.i_links_count == 0 ||
> @@ -248,16 +252,19 @@ extents_loaded:
>  	memset(inode.i_block, 0, sizeof(inode.i_block));
>  
>  	/* Make a note of freed blocks */
> -	retval = ext2fs_iblk_sub_blocks(ctx->fs, &inode, list->blocks_freed);
> +	quota_data_sub(ctx->qctx, &inode, ino,
> +		       list->blocks_freed * ctx->fs->blocksize);
> +	retval = ext2fs_iblk_sub_blocks(ctx->fs, inode_ptr, list->blocks_freed);
>  	if (retval)
>  		goto err;
>  
>  	/* Now stuff extents into the file */
> -	retval = ext2fs_extent_open2(ctx->fs, ino, &inode, &handle);
> +	retval = ext2fs_extent_open2(ctx->fs, ino, inode_ptr, &handle);
>  	if (retval)
>  		goto err;
>  
>  	ext_written = 0;
> +	start_val = ctx->clusters_allocated;
>  	for (i = 0, ex = list->extents; i < list->count; i++, ex++) {
>  		memcpy(&extent, ex, sizeof(struct ext2fs_extent));
>  		extent.e_flags &= EXT2_EXTENT_FLAGS_UNINIT;
> @@ -295,11 +302,17 @@ extents_loaded:
>  		ext_written++;
>  	}
>  
> +	if (start_val != ctx->clusters_allocated) {
> +		__u32 num = ctx->clusters_allocated - start_val;
> +		quota_data_add(ctx->qctx, &inode, ino,
> +			       num * ctx->fs->blocksize);
> +	}

Why not calculate the change in quota use by comparing the inode's
i_blocks in between the ext2fs_iblk_sub_blocks call and the end of the
ext2fs_extent_insert loop, rather than adding a counter to the global
e2fsck state?

--D

> +
>  #if defined(DEBUG) || defined(DEBUG_SUMMARY)
>  	printf("rebuild: ino=%d extents=%d->%d\n", ino, list->ext_read,
>  	       ext_written);
>  #endif
> -	e2fsck_write_inode(ctx, ino, &inode, "rebuild_extents");
> +	e2fsck_write_inode(ctx, ino, inode_ptr, "rebuild_extents");
>  
>  err2:
>  	ext2fs_extent_free(handle);
> diff --git a/e2fsck/pass1.c b/e2fsck/pass1.c
> index 188cc562..99e8f66a 100644
> --- a/e2fsck/pass1.c
> +++ b/e2fsck/pass1.c
> @@ -4017,6 +4017,7 @@ static errcode_t e2fsck_get_alloc_block(ext2_filsys fs, blk64_t goal,
>  	}
>  
>  	*ret = new_block;
> +	ctx->clusters_allocated++;
>  	return (0);
>  }
>  
> -- 
> 2.11.0.rc0.7.gbe5a750
>