[PATCH 20/30] db: verify and calculate inode CRCs

Dave Chinner
2013-10-30T04:31:37Z

From: Dave Chinner <dchinner@redhat.com>

When we set the current Io cursor to point at an inode, verify that
the inode CRC is intact. And prior to writing such an IO cursor,
calculate the inode CRC.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
---
db/inode.c | 2 ++
db/io.c | 4 ++++
db/io.h | 6 +++++-
include/libxfs.h | 4 ++++
libxfs/xfs_inode_buf.c | 8 ++++----
5 files changed, 19 insertions(+), 5 deletions(-)

diff --git a/db/inode.c b/db/inode.c
index ec533ee..4090855 100644
--- a/db/inode.c
+++ b/db/inode.c
@@ -655,6 +655,8 @@ set_cur_inode(
blkbb, DB_RING_IGN, NULL);
off_cur(offset << mp->m_sb.sb_inodelog, mp->m_sb.sb_inodesize);
dip = iocur_top->data;
+ iocur_top->ino_crc_ok = libxfs_dinode_verify(mp, ino, dip);
+ iocur_top->ino_buf = 1;
iocur_top->ino = ino;
iocur_top->mode = be16_to_cpu(dip->di_mode);
if ((iocur_top->mode & S_IFMT) == S_IFDIR)
diff --git a/db/io.c b/db/io.c
index c9452f2..8ddb5e5 100644
--- a/db/io.c
+++ b/db/io.c
@@ -462,6 +462,9 @@ write_cur(void)
return;
}

+ if (iocur_top->ino_buf)
+ libxfs_dinode_calc_crc(mp, iocur_top->data);
+
if (iocur_top->bbmap)
write_cur_bbs();
else
@@ -534,6 +537,7 @@ set_cur(
iocur_top->ino = ino;
iocur_top->dirino = dirino;
iocur_top->mode = mode;
+ iocur_top->ino_buf = 0;

/* store location in ring */
if (ring_flag)
diff --git a/db/io.h b/db/io.h
index d647284..1f8270d 100644
--- a/db/io.h
+++ b/db/io.h
@@ -38,6 +38,8 @@ typedef struct iocur {
const struct typ *typ; /* type of "data" */
bbmap_t *bbmap; /* map daddr if fragmented */
struct xfs_buf *bp; /* underlying buffer */
+ int ino_crc_ok:1;
+ int ino_buf:1;
} iocur_t;

#define DB_RING_ADD 1 /* add to ring on set_cur */
@@ -62,5 +64,7 @@ extern void ring_add(void);
static inline bool
iocur_crc_valid()
{
- return (iocur_top->bp && iocur_top->bp->b_error != EFSCORRUPTED);
+ return (iocur_top->bp &&
+ iocur_top->bp->b_error != EFSCORRUPTED &&
+ (!iocur_top->ino_buf || iocur_top->ino_crc_ok));
}
diff --git a/include/libxfs.h b/include/libxfs.h
index 08fd0b3..d28ac48 100644
--- a/include/libxfs.h
+++ b/include/libxfs.h
@@ -755,6 +755,10 @@ void xfs_dinode_from_disk(struct xfs_icdinode *,
#define libxfs_idata_realloc xfs_idata_realloc
#define libxfs_idestroy_fork xfs_idestroy_fork

+#define libxfs_dinode_verify xfs_dinode_verify
+bool xfs_dinode_verify(struct xfs_mount *mp, xfs_ino_t ino,
+ struct xfs_dinode *dip);
+
/* xfs_sb.h */
#define libxfs_mod_sb xfs_mod_sb
#define libxfs_sb_from_disk xfs_sb_from_disk
diff --git a/libxfs/xfs_inode_buf.c b/libxfs/xfs_inode_buf.c
index b796556..728ef71 100644
--- a/libxfs/xfs_inode_buf.c
+++ b/libxfs/xfs_inode_buf.c
@@ -276,10 +276,10 @@ xfs_dinode_to_disk(
}
}

-static bool
+bool
xfs_dinode_verify(
struct xfs_mount *mp,
- struct xfs_inode *ip,
+ xfs_ino_t ino,
struct xfs_dinode *dip)
{
if (dip->di_magic != cpu_to_be16(XFS_DINODE_MAGIC))
@@ -294,7 +294,7 @@ xfs_dinode_verify(
if (!xfs_verify_cksum((char *)dip, mp->m_sb.sb_inodesize,
offsetof(struct xfs_dinode, di_crc)))
return false;
- if (be64_to_cpu(dip->di_ino) != ip->i_ino)
+ if (be64_to_cpu(dip->di_ino) != ino)
return false;
if (!uuid_equal(&dip->di_uuid, &mp->m_sb.sb_uuid))
return false;
@@ -346,7 +346,7 @@ xfs_iread(
return error;

/* even unallocated inodes are verified */
- if (!xfs_dinode_verify(mp, ip, dip)) {
+ if (!xfs_dinode_verify(mp, ip->i_ino, dip)) {
xfs_alert(mp, "%s: validation failed for inode %lld failed",
__func__, ip->i_ino);

--
1.8.4.rc3