lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

[XFS] factor out xfs_read_agf helper

Browse Source 
Add a helper to read the AGF header and perform basic verification.
Based on hunks from a larger patch from Dave Chinner.

(First sent on Juli 23rd)

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Niv Sardi <xaiki@sgi.com>
This commit is contained in:
From: Christoph Hellwig
2008-11-28 14:23:38 +11:00
committed by Niv Sardi
parent 5e1be0fb1a
commit 4805621a37
3 changed files with 61 additions and 36 deletions
Download Patch File Download Diff File Expand all files Collapse all files

69
fs/xfs/xfs_alloc.c
View File

@@ -2233,44 +2233,41 @@ xfs_alloc_put_freelist(
* Read in the allocation group header (free/alloc section).
*/
int /* error */
xfs_alloc_read_agf(
xfs_mount_t *mp, /* mount point structure */
xfs_trans_t *tp, /* transaction pointer */
xfs_agnumber_t agno, /* allocation group number */
int flags, /* XFS_ALLOC_FLAG_... */
xfs_buf_t **bpp) /* buffer for the ag freelist header */
xfs_read_agf(
struct xfs_mount *mp, /* mount point structure */
struct xfs_trans *tp, /* transaction pointer */
xfs_agnumber_t agno, /* allocation group number */
int flags, /* XFS_BUF_ */
struct xfs_buf **bpp) /* buffer for the ag freelist header */
{
xfs_agf_t *agf; /* ag freelist header */
struct xfs_agf *agf; /* ag freelist header */
int agf_ok; /* set if agf is consistent */
xfs_buf_t *bp; /* return value */
xfs_perag_t *pag; /* per allocation group data */
int error;
ASSERT(agno != NULLAGNUMBER);
error = xfs_trans_read_buf(
mp, tp, mp->m_ddev_targp,
XFS_AG_DADDR(mp, agno, XFS_AGF_DADDR(mp)),
XFS_FSS_TO_BB(mp, 1),
(flags & XFS_ALLOC_FLAG_TRYLOCK) ? XFS_BUF_TRYLOCK : 0U,
&bp);
XFS_FSS_TO_BB(mp, 1), flags, bpp);
if (error)
return error;
ASSERT(!bp || !XFS_BUF_GETERROR(bp));
if (!bp) {
*bpp = NULL;
if (!*bpp)
return 0;
}
ASSERT(!XFS_BUF_GETERROR(*bpp));
agf = XFS_BUF_TO_AGF(*bpp);
/*
* Validate the magic number of the agf block.
*/
agf = XFS_BUF_TO_AGF(bp);
agf_ok =
be32_to_cpu(agf->agf_magicnum) == XFS_AGF_MAGIC &&
XFS_AGF_GOOD_VERSION(be32_to_cpu(agf->agf_versionnum)) &&
be32_to_cpu(agf->agf_freeblks) <= be32_to_cpu(agf->agf_length) &&
be32_to_cpu(agf->agf_flfirst) < XFS_AGFL_SIZE(mp) &&
be32_to_cpu(agf->agf_fllast) < XFS_AGFL_SIZE(mp) &&
be32_to_cpu(agf->agf_flcount) <= XFS_AGFL_SIZE(mp);
be32_to_cpu(agf->agf_flcount) <= XFS_AGFL_SIZE(mp) &&
be32_to_cpu(agf->agf_seqno) == agno;
if (xfs_sb_version_haslazysbcount(&mp->m_sb))
agf_ok = agf_ok && be32_to_cpu(agf->agf_btreeblks) <=
be32_to_cpu(agf->agf_length);
@@ -2278,9 +2275,41 @@ xfs_alloc_read_agf(
XFS_RANDOM_ALLOC_READ_AGF))) {
XFS_CORRUPTION_ERROR("xfs_alloc_read_agf",
XFS_ERRLEVEL_LOW, mp, agf);
xfs_trans_brelse(tp, bp);
xfs_trans_brelse(tp, *bpp);
return XFS_ERROR(EFSCORRUPTED);
}
XFS_BUF_SET_VTYPE_REF(*bpp, B_FS_AGF, XFS_AGF_REF);
return 0;
}
/*
* Read in the allocation group header (free/alloc section).
*/
int /* error */
xfs_alloc_read_agf(
struct xfs_mount *mp, /* mount point structure */
struct xfs_trans *tp, /* transaction pointer */
xfs_agnumber_t agno, /* allocation group number */
int flags, /* XFS_ALLOC_FLAG_... */
struct xfs_buf **bpp) /* buffer for the ag freelist header */
{
struct xfs_agf *agf; /* ag freelist header */
struct xfs_perag *pag; /* per allocation group data */
int error;
ASSERT(agno != NULLAGNUMBER);
error = xfs_read_agf(mp, tp, agno,
(flags & XFS_ALLOC_FLAG_TRYLOCK) ? XFS_BUF_TRYLOCK : 0,
bpp);
if (error)
return error;
if (!*bpp)
return 0;
ASSERT(!XFS_BUF_GETERROR(*bpp));
agf = XFS_BUF_TO_AGF(*bpp);
pag = &mp->m_perag[agno];
if (!pag->pagf_init) {
pag->pagf_freeblks = be32_to_cpu(agf->agf_freeblks);
@@ -2308,8 +2337,6 @@ xfs_alloc_read_agf(
be32_to_cpu(agf->agf_levels[XFS_BTNUM_CNTi]));
}
#endif
XFS_BUF_SET_VTYPE_REF(bp, B_FS_AGF, XFS_AGF_REF);
*bpp = bp;
return 0;
}