Re: [PATCH 4/4] btrfs: add tree-checker for RAID-stripe-tree

From: Qu Wenruo
Date: Mon Sep 18 2023 - 20:31:10 EST




On 2023/9/18 23:44, Johannes Thumshirn wrote:
Add a tree checker for RAID stripe tree items.

Signed-off-by: Johannes Thumshirn <johannes.thumshirn@xxxxxxx>
---
fs/btrfs/tree-checker.c | 42 ++++++++++++++++++++++++++++++++++++++++++
1 file changed, 42 insertions(+)

diff --git a/fs/btrfs/tree-checker.c b/fs/btrfs/tree-checker.c
index 01bba79165e7..ea84ca2767e9 100644
--- a/fs/btrfs/tree-checker.c
+++ b/fs/btrfs/tree-checker.c
@@ -30,6 +30,7 @@
#include "file-item.h"
#include "inode-item.h"
#include "dir-item.h"
+#include "raid-stripe-tree.h"

/*
* Error message should follow the following format:
@@ -1635,6 +1636,44 @@ static int check_inode_ref(struct extent_buffer *leaf,
return 0;
}

+static int check_raid_stripe_extent(struct extent_buffer *leaf,
+ struct btrfs_key *key, int slot)
+{
+ struct btrfs_stripe_extent *stripe_extent =
+ btrfs_item_ptr(leaf, slot, struct btrfs_stripe_extent);
+
+ if (unlikely(!IS_ALIGNED(key->objectid, leaf->fs_info->sectorsize))) {
+ generic_err(leaf, slot,
+"invalid key objectid for raid stripe extent, have %llu expect aligned to %u",
+ key->objectid, leaf->fs_info->sectorsize);
+ return -EUCLEAN;
+ }
+
+ if (unlikely(!btrfs_fs_incompat(leaf->fs_info, RAID_STRIPE_TREE))) {
+ generic_err(leaf, slot,
+ "RAID_STRIPE_EXTENT present but RAID_STRIPE_TREE incompat bit unset");
+ return -EUCLEAN;
+ }
+
+ switch (btrfs_stripe_extent_encoding(leaf, stripe_extent)) {
+ case BTRFS_STRIPE_RAID0:
+ case BTRFS_STRIPE_RAID1:
+ case BTRFS_STRIPE_DUP:
+ case BTRFS_STRIPE_RAID10:
+ case BTRFS_STRIPE_RAID5:
+ case BTRFS_STRIPE_RAID6:
+ case BTRFS_STRIPE_RAID1C3:
+ case BTRFS_STRIPE_RAID1C4:
+ break;
+ default:
+ generic_err(leaf, slot, "invalid raid stripe encoding %u",
+ btrfs_stripe_extent_encoding(leaf, stripe_extent));
+ return -EUCLEAN;
+ }

Another thing we can check is the item size, the item size should be
aligned to a single record, or we can get garbage reading the last record.

Thanks,
Qu
+
+ return 0;
+}
+
/*
* Common point to switch the item-specific validation.
*/
@@ -1689,6 +1728,9 @@ static enum btrfs_tree_block_status check_leaf_item(struct extent_buffer *leaf,
case BTRFS_EXTENT_DATA_REF_KEY:
ret = check_extent_data_ref(leaf, key, slot);
break;
+ case BTRFS_RAID_STRIPE_KEY:
+ ret = check_raid_stripe_extent(leaf, key, slot);
+ break;
}

if (ret)