[PATCH v3 9/9] xfs: factor xfs_da3_blkinfo verification into common helper

Brian Foster
2019-02-04T14:52:36Z

With the verifier magic value helper in place, we've left a bit more
duplicate code across the verifiers that involve struct
xfs_da3_blkinfo. This includes the da node, xattr leaf and dir leaf
verifiers, all of which perform similar checks for v4 and v5
filesystems.

Create a common helper to verify an xfs_da3_blkinfo structure,
taking care to only access v5 fields where appropriate, and refactor
the aforementioned verifiers to use the helper. No functional
changes.

Signed-off-by: Brian Foster <bfoster@redhat.com>
---
fs/xfs/libxfs/xfs_attr_leaf.c | 17 +++----------
fs/xfs/libxfs/xfs_da_btree.c | 46 +++++++++++++++++++++++++----------
fs/xfs/libxfs/xfs_da_format.h | 3 +++
fs/xfs/libxfs/xfs_dir2_leaf.c | 18 +++-----------
4 files changed, 44 insertions(+), 40 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_attr_leaf.c b/fs/xfs/libxfs/xfs_attr_leaf.c
index dde3a550d7ce..0c92987f57fc 100644
--- a/fs/xfs/libxfs/xfs_attr_leaf.c
+++ b/fs/xfs/libxfs/xfs_attr_leaf.c
@@ -245,23 +245,14 @@ xfs_attr3_leaf_verify(
struct xfs_attr_leaf_entry *entries;
uint32_t end; /* must be 32bit - see below */
int i;
+ xfs_failaddr_t fa;

xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr, leaf);

- if (!xfs_verify_magic(bp, leaf->hdr.info.magic))
- return __this_address;
-
- if (xfs_sb_version_hascrc(&mp->m_sb)) {
- struct xfs_da3_node_hdr *hdr3 = bp->b_addr;
+ fa = xfs_da3_blkinfo_verify(bp, bp->b_addr);
+ if (fa)
+ return fa;

- ASSERT(leaf->hdr.info.magic == hdr3->info.hdr.magic);
- if (!uuid_equal(&hdr3->info.uuid, &mp->m_sb.sb_meta_uuid))
- return __this_address;
- if (be64_to_cpu(hdr3->info.blkno) != bp->b_bn)
- return __this_address;
- if (!xfs_log_check_lsn(mp, be64_to_cpu(hdr3->info.lsn)))
- return __this_address;
- }
/*
* In recovery there is a transient state where count == 0 is valid
* because we may have transitioned an empty shortform attr to a leaf
diff --git a/fs/xfs/libxfs/xfs_da_btree.c b/fs/xfs/libxfs/xfs_da_btree.c
index 6b8ca390eecc..622f88a1b1aa 100644
--- a/fs/xfs/libxfs/xfs_da_btree.c
+++ b/fs/xfs/libxfs/xfs_da_btree.c
@@ -116,6 +116,35 @@ xfs_da_state_free(xfs_da_state_t *state)
kmem_zone_free(xfs_da_state_zone, state);
}

+/*
+ * Verify an xfs_da3_blkinfo structure. Note that the da3 fields are only
+ * accessible on v5 filesystems. This header format is common across da node,
+ * attr leaf and dir leaf blocks.
+ */
+xfs_failaddr_t
+xfs_da3_blkinfo_verify(
+ struct xfs_buf *bp,
+ struct xfs_da3_blkinfo *hdr3)
+{
+ struct xfs_mount *mp = bp->b_target->bt_mount;
+ struct xfs_da_blkinfo *hdr = &hdr3->hdr;
+
+ if (!xfs_verify_magic(bp, hdr->magic))
+ return __this_address;
+
+ if (xfs_sb_version_hascrc(&mp->m_sb)) {
+ ASSERT(hdr3->hdr.magic == hdr->magic);
+ if (!uuid_equal(&hdr3->uuid, &mp->m_sb.sb_meta_uuid))
+ return __this_address;
+ if (be64_to_cpu(hdr3->blkno) != bp->b_bn)
+ return __this_address;
+ if (!xfs_log_check_lsn(mp, be64_to_cpu(hdr3->lsn)))
+ return __this_address;
+ }
+
+ return 0;
+}
+
static xfs_failaddr_t
xfs_da3_node_verify(
struct xfs_buf *bp)
@@ -124,25 +153,16 @@ xfs_da3_node_verify(
struct xfs_da_intnode *hdr = bp->b_addr;
struct xfs_da3_icnode_hdr ichdr;
const struct xfs_dir_ops *ops;
+ xfs_failaddr_t fa;

ops = xfs_dir_get_ops(mp, NULL);

ops->node_hdr_from_disk(&ichdr, hdr);

- if (!xfs_verify_magic(bp, hdr->hdr.info.magic))
- return __this_address;
+ fa = xfs_da3_blkinfo_verify(bp, bp->b_addr);
+ if (fa)
+ return fa;

- if (xfs_sb_version_hascrc(&mp->m_sb)) {
- struct xfs_da3_node_hdr *hdr3 = bp->b_addr;
-
- ASSERT(hdr3->info.hdr.magic == hdr->hdr.info.magic);
- if (!uuid_equal(&hdr3->info.uuid, &mp->m_sb.sb_meta_uuid))
- return __this_address;
- if (be64_to_cpu(hdr3->info.blkno) != bp->b_bn)
- return __this_address;
- if (!xfs_log_check_lsn(mp, be64_to_cpu(hdr3->info.lsn)))
- return __this_address;
- }
if (ichdr.level == 0)
return __this_address;
if (ichdr.level > XFS_DA_NODE_MAXDEPTH)
diff --git a/fs/xfs/libxfs/xfs_da_format.h b/fs/xfs/libxfs/xfs_da_format.h
index 5d5bf3bffc78..ae654e06b2fb 100644
--- a/fs/xfs/libxfs/xfs_da_format.h
+++ b/fs/xfs/libxfs/xfs_da_format.h
@@ -869,4 +869,7 @@ static inline unsigned int xfs_dir2_dirblock_bytes(struct xfs_sb *sbp)
return 1 << (sbp->sb_blocklog + sbp->sb_dirblklog);
}

+xfs_failaddr_t xfs_da3_blkinfo_verify(struct xfs_buf *bp,
+ struct xfs_da3_blkinfo *hdr3);
+
#endif /* __XFS_DA_FORMAT_H__ */
diff --git a/fs/xfs/libxfs/xfs_dir2_leaf.c b/fs/xfs/libxfs/xfs_dir2_leaf.c
index a99ae2cd292e..094028b7b162 100644
--- a/fs/xfs/libxfs/xfs_dir2_leaf.c
+++ b/fs/xfs/libxfs/xfs_dir2_leaf.c
@@ -146,21 +146,11 @@ xfs_dir3_leaf_verify(
{
struct xfs_mount *mp = bp->b_target->bt_mount;
struct xfs_dir2_leaf *leaf = bp->b_addr;
+ xfs_failaddr_t fa;

- if (!xfs_verify_magic(bp, leaf->hdr.info.magic))
- return __this_address;
-
- if (xfs_sb_version_hascrc(&mp->m_sb)) {
- struct xfs_dir3_leaf_hdr *leaf3 = bp->b_addr;
-
- ASSERT(leaf3->info.hdr.magic == leaf->hdr.info.magic);
- if (!uuid_equal(&leaf3->info.uuid, &mp->m_sb.sb_meta_uuid))
- return __this_address;
- if (be64_to_cpu(leaf3->info.blkno) != bp->b_bn)
- return __this_address;
- if (!xfs_log_check_lsn(mp, be64_to_cpu(leaf3->info.lsn)))
- return __this_address;
- }
+ fa = xfs_da3_blkinfo_verify(bp, bp->b_addr);
+ if (fa)
+ return fa;

return xfs_dir3_leaf_check_int(mp, NULL, NULL, leaf);
}
--
2.17.2