linux/fs/xfs/scrub/rtbitmap.c
Darrick J. Wong 881f78f472 xfs: remove conditional building of rt geometry validator functions
I mistakenly turned off CONFIG_XFS_RT in the Kconfig file for arm64
variant of the djwong-wtf git branch.  Unfortunately, it took me a good
hour to figure out that RT wasn't built because this is what got printed
to dmesg:

XFS (sda2): realtime geometry sanity check failed
XFS (sda2): Metadata corruption detected at xfs_sb_read_verify+0x170/0x190 [xfs], xfs_sb block 0x0

Whereas I would have expected:

XFS (sda2): Not built with CONFIG_XFS_RT
XFS (sda2): RT mount failed

The root cause of these problems is the conditional compilation of the
new functions xfs_validate_rtextents and xfs_compute_rextslog that I
introduced in the two commits listed below.  The !RT versions of these
functions return false and 0, respectively, which causes primary
superblock validation to fail, which explains the first message.

Move the two functions to other parts of libxfs that are not
conditionally defined by CONFIG_XFS_RT and remove the broken stubs so
that validation works again.

Fixes: e14293803f ("xfs: don't allow overly small or large realtime volumes")
Fixes: a6a38f309a ("xfs: make rextslog computation consistent with mkfs")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
2024-01-30 14:04:43 +05:30

230 lines
5.6 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2017-2023 Oracle. All Rights Reserved.
* Author: Darrick J. Wong <djwong@kernel.org>
*/
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_shared.h"
#include "xfs_format.h"
#include "xfs_trans_resv.h"
#include "xfs_mount.h"
#include "xfs_log_format.h"
#include "xfs_trans.h"
#include "xfs_rtbitmap.h"
#include "xfs_inode.h"
#include "xfs_bmap.h"
#include "xfs_bit.h"
#include "xfs_sb.h"
#include "scrub/scrub.h"
#include "scrub/common.h"
#include "scrub/repair.h"
#include "scrub/rtbitmap.h"
/* Set us up with the realtime metadata locked. */
int
xchk_setup_rtbitmap(
struct xfs_scrub *sc)
{
struct xfs_mount *mp = sc->mp;
struct xchk_rtbitmap *rtb;
int error;
rtb = kzalloc(sizeof(struct xchk_rtbitmap), XCHK_GFP_FLAGS);
if (!rtb)
return -ENOMEM;
sc->buf = rtb;
if (xchk_could_repair(sc)) {
error = xrep_setup_rtbitmap(sc, rtb);
if (error)
return error;
}
error = xchk_trans_alloc(sc, rtb->resblks);
if (error)
return error;
error = xchk_install_live_inode(sc, sc->mp->m_rbmip);
if (error)
return error;
error = xchk_ino_dqattach(sc);
if (error)
return error;
xchk_ilock(sc, XFS_ILOCK_EXCL | XFS_ILOCK_RTBITMAP);
/*
* Now that we've locked the rtbitmap, we can't race with growfsrt
* trying to expand the bitmap or change the size of the rt volume.
* Hence it is safe to compute and check the geometry values.
*/
if (mp->m_sb.sb_rblocks) {
rtb->rextents = xfs_rtb_to_rtx(mp, mp->m_sb.sb_rblocks);
rtb->rextslog = xfs_compute_rextslog(rtb->rextents);
rtb->rbmblocks = xfs_rtbitmap_blockcount(mp, rtb->rextents);
}
return 0;
}
/* Realtime bitmap. */
/* Scrub a free extent record from the realtime bitmap. */
STATIC int
xchk_rtbitmap_rec(
struct xfs_mount *mp,
struct xfs_trans *tp,
const struct xfs_rtalloc_rec *rec,
void *priv)
{
struct xfs_scrub *sc = priv;
xfs_rtblock_t startblock;
xfs_filblks_t blockcount;
startblock = xfs_rtx_to_rtb(mp, rec->ar_startext);
blockcount = xfs_rtx_to_rtb(mp, rec->ar_extcount);
if (!xfs_verify_rtbext(mp, startblock, blockcount))
xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, 0);
return 0;
}
/* Make sure the entire rtbitmap file is mapped with written extents. */
STATIC int
xchk_rtbitmap_check_extents(
struct xfs_scrub *sc)
{
struct xfs_bmbt_irec map;
struct xfs_iext_cursor icur;
struct xfs_mount *mp = sc->mp;
struct xfs_inode *ip = sc->ip;
xfs_fileoff_t off = 0;
xfs_fileoff_t endoff;
int error = 0;
/* Mappings may not cross or lie beyond EOF. */
endoff = XFS_B_TO_FSB(mp, ip->i_disk_size);
if (xfs_iext_lookup_extent(ip, &ip->i_df, endoff, &icur, &map)) {
xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, endoff);
return 0;
}
while (off < endoff) {
int nmap = 1;
if (xchk_should_terminate(sc, &error) ||
(sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT))
break;
/* Make sure we have a written extent. */
error = xfs_bmapi_read(ip, off, endoff - off, &map, &nmap,
XFS_DATA_FORK);
if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, off, &error))
break;
if (nmap != 1 || !xfs_bmap_is_written_extent(&map)) {
xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, off);
break;
}
off += map.br_blockcount;
}
return error;
}
/* Scrub the realtime bitmap. */
int
xchk_rtbitmap(
struct xfs_scrub *sc)
{
struct xfs_mount *mp = sc->mp;
struct xchk_rtbitmap *rtb = sc->buf;
int error;
/* Is sb_rextents correct? */
if (mp->m_sb.sb_rextents != rtb->rextents) {
xchk_ino_set_corrupt(sc, mp->m_rbmip->i_ino);
return 0;
}
/* Is sb_rextslog correct? */
if (mp->m_sb.sb_rextslog != rtb->rextslog) {
xchk_ino_set_corrupt(sc, mp->m_rbmip->i_ino);
return 0;
}
/*
* Is sb_rbmblocks large enough to handle the current rt volume? In no
* case can we exceed 4bn bitmap blocks since the super field is a u32.
*/
if (rtb->rbmblocks > U32_MAX) {
xchk_ino_set_corrupt(sc, mp->m_rbmip->i_ino);
return 0;
}
if (mp->m_sb.sb_rbmblocks != rtb->rbmblocks) {
xchk_ino_set_corrupt(sc, mp->m_rbmip->i_ino);
return 0;
}
/* The bitmap file length must be aligned to an fsblock. */
if (mp->m_rbmip->i_disk_size & mp->m_blockmask) {
xchk_ino_set_corrupt(sc, mp->m_rbmip->i_ino);
return 0;
}
/*
* Is the bitmap file itself large enough to handle the rt volume?
* growfsrt expands the bitmap file before updating sb_rextents, so the
* file can be larger than sb_rbmblocks.
*/
if (mp->m_rbmip->i_disk_size < XFS_FSB_TO_B(mp, rtb->rbmblocks)) {
xchk_ino_set_corrupt(sc, mp->m_rbmip->i_ino);
return 0;
}
/* Invoke the fork scrubber. */
error = xchk_metadata_inode_forks(sc);
if (error || (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT))
return error;
error = xchk_rtbitmap_check_extents(sc);
if (error || (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT))
return error;
error = xfs_rtalloc_query_all(mp, sc->tp, xchk_rtbitmap_rec, sc);
if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, 0, &error))
return error;
return 0;
}
/* xref check that the extent is not free in the rtbitmap */
void
xchk_xref_is_used_rt_space(
struct xfs_scrub *sc,
xfs_rtblock_t rtbno,
xfs_extlen_t len)
{
xfs_rtxnum_t startext;
xfs_rtxnum_t endext;
bool is_free;
int error;
if (xchk_skip_xref(sc->sm))
return;
startext = xfs_rtb_to_rtx(sc->mp, rtbno);
endext = xfs_rtb_to_rtx(sc->mp, rtbno + len - 1);
xfs_ilock(sc->mp->m_rbmip, XFS_ILOCK_SHARED | XFS_ILOCK_RTBITMAP);
error = xfs_rtalloc_extent_is_free(sc->mp, sc->tp, startext,
endext - startext + 1, &is_free);
if (!xchk_should_check_xref(sc, &error, NULL))
goto out_unlock;
if (is_free)
xchk_ino_xref_set_corrupt(sc, sc->mp->m_rbmip->i_ino);
out_unlock:
xfs_iunlock(sc->mp->m_rbmip, XFS_ILOCK_SHARED | XFS_ILOCK_RTBITMAP);
}