Re: [PATCH V3] resize2fs: clear uninit BG if allocating from new group
From: Eric Sandeen <hidden>
Date: 2016-01-14 19:57:15
On 1/14/16 1:27 PM, Eric Sandeen wrote:
If resize2fs_get_alloc_block() allocates from a BLOCK_UNINIT group, nothing clears the UNINIT flag, so it is skipped when we go to write out modified bitmaps. This leads to post-resize2fs e2fsck errors; used blocks in UNINIT groups, not marked in the block bitmap. This was seen on r_ext4_small_bg. This patch uses clear_block_uninit() to clear the flag, and my problem goes away.
Ted, if you want to clarify the commit log, I realized that the issue here is that although we are called via ->get_alloc_block, and the caller clears uninit after the call, in resize-land we have *2* filesystems to deal with, hanging off the fs private pointer. Explicitly clearing uninit in both filesystems in the resize code seems like the safest path.
quoted hunk ↗ jump to hunk
Signed-off-by: Eric Sandeen <redacted> --- V2: don't cut and paste, sorry! V3: ext2fs_* namespace for the exported function, thanks Darrick Thanks, -Ericdiff --git a/lib/ext2fs/alloc.c b/lib/ext2fs/alloc.c index 86e7f99..ce59e85 100644 --- a/lib/ext2fs/alloc.c +++ b/lib/ext2fs/alloc.c@@ -39,7 +39,7 @@ /* * Clear the uninit block bitmap flag if necessary */ -static void clear_block_uninit(ext2_filsys fs, dgrp_t group) +void ext2fs_clear_block_uninit(ext2_filsys fs, dgrp_t group) { if (!ext2fs_has_group_desc_csum(fs) || !(ext2fs_bg_flags_test(fs, group, EXT2_BG_BLOCK_UNINIT)))@@ -183,7 +183,7 @@ allocated: if (retval) return retval; - clear_block_uninit(fs, ext2fs_group_of_blk2(fs, b)); + ext2fs_clear_block_uninit(fs, ext2fs_group_of_blk2(fs, b)); *ret = b; return 0; }@@ -455,7 +455,7 @@ errcode_t ext2fs_new_range(ext2_filsys fs, int flags, blk64_t goal, allocated: for (b = start; b < end; b += fs->super->s_blocks_per_group) - clear_block_uninit(fs, + ext2fs_clear_block_uninit(fs, ext2fs_group_of_blk2(fs, b)); return 0; }diff --git a/lib/ext2fs/ext2fs.h b/lib/ext2fs/ext2fs.h index 86d860f..d5e9684 100644 --- a/lib/ext2fs/ext2fs.h +++ b/lib/ext2fs/ext2fs.h@@ -647,6 +647,7 @@ static inline int ext2fs_needs_large_file_feature(unsigned long long file_size) } /* alloc.c */ +extern void ext2fs_clear_block_uninit(ext2_filsys fs, dgrp_t group); extern errcode_t ext2fs_new_inode(ext2_filsys fs, ext2_ino_t dir, int mode, ext2fs_inode_bitmap map, ext2_ino_t *ret); extern errcode_t ext2fs_new_block(ext2_filsys fs, blk_t goal,diff --git a/resize/resize2fs.c b/resize/resize2fs.c index 07c6a0c..42435b2 100644 --- a/resize/resize2fs.c +++ b/resize/resize2fs.c@@ -1620,6 +1620,7 @@ static errcode_t resize2fs_get_alloc_block(ext2_filsys fs, { ext2_resize_t rfs = (ext2_resize_t) fs->priv_data; blk64_t blk; + int group; blk = get_new_block(rfs); if (!blk)@@ -1632,6 +1633,12 @@ static errcode_t resize2fs_get_alloc_block(ext2_filsys fs, ext2fs_mark_block_bitmap2(rfs->old_fs->block_map, blk); ext2fs_mark_block_bitmap2(rfs->new_fs->block_map, blk); + + group = ext2fs_group_of_blk2(rfs->old_fs, blk); + ext2fs_clear_block_uninit(rfs->old_fs, group); + group = ext2fs_group_of_blk2(rfs->new_fs, blk); + ext2fs_clear_block_uninit(rfs->new_fs, group); + *ret = (blk64_t) blk; return 0; } --To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html