xfs: verify AGI blocks as they are read from disk

Add an AGI block verify callback function and pass it into the
buffer read functions. Remove the now redundant verification code
that is currently in use.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>
This commit is contained in:
Dave Chinner 2012-11-12 22:54:05 +11:00 committed by Ben Myers
parent 5d5f527d13
commit 3702ce6ed7
1 changed files with 35 additions and 21 deletions

View File

@ -1472,6 +1472,40 @@ xfs_check_agi_unlinked(
#define xfs_check_agi_unlinked(agi)
#endif
static void
xfs_agi_read_verify(
struct xfs_buf *bp)
{
struct xfs_mount *mp = bp->b_target->bt_mount;
struct xfs_agi *agi = XFS_BUF_TO_AGI(bp);
int agi_ok;
/*
* Validate the magic number of the agi block.
*/
agi_ok = agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC) &&
XFS_AGI_GOOD_VERSION(be32_to_cpu(agi->agi_versionnum));
/*
* during growfs operations, the perag is not fully initialised,
* so we can't use it for any useful checking. growfs ensures we can't
* use it by using uncached buffers that don't have the perag attached
* so we can detect and avoid this problem.
*/
if (bp->b_pag)
agi_ok = agi_ok && be32_to_cpu(agi->agi_seqno) ==
bp->b_pag->pag_agno;
if (unlikely(XFS_TEST_ERROR(!agi_ok, mp, XFS_ERRTAG_IALLOC_READ_AGI,
XFS_RANDOM_IALLOC_READ_AGI))) {
XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, agi);
xfs_buf_ioerror(bp, EFSCORRUPTED);
}
xfs_check_agi_unlinked(agi);
bp->b_iodone = NULL;
xfs_buf_ioend(bp, 0);
}
/*
* Read in the allocation group header (inode allocation section)
*/
@ -1482,38 +1516,18 @@ xfs_read_agi(
xfs_agnumber_t agno, /* allocation group number */
struct xfs_buf **bpp) /* allocation group hdr buf */
{
struct xfs_agi *agi; /* allocation group header */
int agi_ok; /* agi is consistent */
int error;
ASSERT(agno != NULLAGNUMBER);
error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp,
XFS_AG_DADDR(mp, agno, XFS_AGI_DADDR(mp)),
XFS_FSS_TO_BB(mp, 1), 0, bpp, NULL);
XFS_FSS_TO_BB(mp, 1), 0, bpp, xfs_agi_read_verify);
if (error)
return error;
ASSERT(!xfs_buf_geterror(*bpp));
agi = XFS_BUF_TO_AGI(*bpp);
/*
* Validate the magic number of the agi block.
*/
agi_ok = agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC) &&
XFS_AGI_GOOD_VERSION(be32_to_cpu(agi->agi_versionnum)) &&
be32_to_cpu(agi->agi_seqno) == agno;
if (unlikely(XFS_TEST_ERROR(!agi_ok, mp, XFS_ERRTAG_IALLOC_READ_AGI,
XFS_RANDOM_IALLOC_READ_AGI))) {
XFS_CORRUPTION_ERROR("xfs_read_agi", XFS_ERRLEVEL_LOW,
mp, agi);
xfs_trans_brelse(tp, *bpp);
return XFS_ERROR(EFSCORRUPTED);
}
xfs_buf_set_ref(*bpp, XFS_AGI_REF);
xfs_check_agi_unlinked(agi);
return 0;
}