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Message-ID: <20141107215329.883.82186.stgit@birch.djwong.org>
Date: Fri, 07 Nov 2014 13:53:29 -0800
From: "Darrick J. Wong" <darrick.wong@...cle.com>
To: tytso@....edu, darrick.wong@...cle.com
Cc: linux-ext4@...r.kernel.org
Subject: [PATCH 25/47] resize2fs: quickly rewrite extent blocks when moving
an inode w/ metadata_csum
When we're moving an inode on a metadata_csum filesystem, we need to
rewrite the checksum of all interior nodes of the extent tree. The
current code does this inefficiently via set_bmap, but we can do this
more efficiently through direct iteration of the extent tree.
Signed-off-by: Darrick J. Wong <darrick.wong@...cle.com>
---
resize/resize2fs.c | 74 +++++++++++++++++++++++++++++++++++++++++++++-------
1 file changed, 64 insertions(+), 10 deletions(-)
diff --git a/resize/resize2fs.c b/resize/resize2fs.c
index 4861719..1415244 100644
--- a/resize/resize2fs.c
+++ b/resize/resize2fs.c
@@ -1492,16 +1492,6 @@ static int process_block(ext2_filsys fs, blk64_t *block_nr,
}
}
- /*
- * If we moved inodes and metadata_csum is enabled, we must force the
- * extent block to be rewritten with new checksum.
- */
- if (EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
- EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
- pb->has_extents &&
- pb->old_ino != pb->ino)
- ret |= BLOCK_CHANGED;
-
if (pb->is_dir) {
retval = ext2fs_add_dir_block2(fs->dblist, pb->ino,
block, (int) blockcnt);
@@ -1581,6 +1571,59 @@ out:
return err;
}
+/* Rewrite extents */
+static errcode_t rewrite_extents(ext2_filsys fs, ext2_ino_t ino)
+{
+ ext2_extent_handle_t handle;
+ struct ext2fs_extent extent;
+ errcode_t errcode;
+ struct ext2_extent_info info;
+
+ errcode = ext2fs_extent_open(fs, ino, &handle);
+ if (errcode)
+ return errcode;
+
+ errcode = ext2fs_extent_get(handle, EXT2_EXTENT_ROOT, &extent);
+ if (errcode)
+ goto out;
+
+ do {
+ errcode = ext2fs_extent_get_info(handle, &info);
+ if (errcode)
+ break;
+
+ /*
+ * If this is the first extent in an extent block that we
+ * haven't visited, rewrite the extent to force the ETB
+ * checksum to be rewritten.
+ */
+ if (info.curr_entry == 1 && info.curr_level != 0 &&
+ !(extent.e_flags & EXT2_EXTENT_FLAGS_SECOND_VISIT)) {
+ errcode = ext2fs_extent_replace(handle, 0, &extent);
+ if (errcode)
+ break;
+ }
+
+ /* Skip to the end of a block of leaf nodes */
+ if (extent.e_flags & EXT2_EXTENT_FLAGS_LEAF) {
+ errcode = ext2fs_extent_get(handle,
+ EXT2_EXTENT_LAST_SIB,
+ &extent);
+ if (errcode)
+ break;
+ }
+
+ errcode = ext2fs_extent_get(handle, EXT2_EXTENT_NEXT, &extent);
+ } while (errcode == 0);
+
+out:
+ /* Ok if we run off the end */
+ if (errcode == EXT2_ET_EXTENT_NO_NEXT)
+ errcode = 0;
+ ext2fs_extent_free(handle);
+ return errcode;
+}
+
static errcode_t inode_scan_and_fix(ext2_resize_t rfs)
{
struct process_block_struct pb;
@@ -1699,6 +1742,17 @@ remap_blocks:
if (retval)
goto errout;
+ /* Rewrite extent block checksums with new inode number */
+ if (EXT2_HAS_RO_COMPAT_FEATURE(rfs->old_fs->super,
+ EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
+ (inode->i_flags & EXT4_EXTENTS_FL)) {
+ rfs->old_fs->flags |= EXT2_FLAG_IGNORE_CSUM_ERRORS;
+ retval = rewrite_extents(rfs->old_fs, new_inode);
+ rfs->old_fs->flags &= ~EXT2_FLAG_IGNORE_CSUM_ERRORS;
+ if (retval)
+ goto errout;
+ }
+
/*
* Update inodes to point to new blocks; schedule directory
* blocks for inode remapping. Need to write out dir blocks
--
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