blob: 8f3cba14ada32a6f6071c38eaf9770a22f84b339 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2018 Oracle. All Rights Reserved.
* Author: Darrick J. Wong <darrick.wong@oracle.com>
*/
#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_btree.h"
#include "xfs_log_format.h"
#include "xfs_trans.h"
#include "xfs_sb.h"
#include "xfs_inode.h"
#include "xfs_alloc.h"
#include "xfs_alloc_btree.h"
#include "xfs_ialloc.h"
#include "xfs_ialloc_btree.h"
#include "xfs_rmap.h"
#include "xfs_rmap_btree.h"
#include "xfs_refcount_btree.h"
#include "xfs_extent_busy.h"
#include "xfs_ag.h"
#include "xfs_ag_resv.h"
#include "xfs_quota.h"
#include "scrub/scrub.h"
#include "scrub/common.h"
#include "scrub/trace.h"
#include "scrub/repair.h"
#include "scrub/bitmap.h"
/*
* Attempt to repair some metadata, if the metadata is corrupt and userspace
* told us to fix it. This function returns -EAGAIN to mean "re-run scrub",
* and will set *fixed to true if it thinks it repaired anything.
*/
int
xrep_attempt(
struct xfs_scrub *sc)
{
int error = 0;
trace_xrep_attempt(XFS_I(file_inode(sc->file)), sc->sm, error);
xchk_ag_btcur_free(&sc->sa);
/* Repair whatever's broken. */
ASSERT(sc->ops->repair);
error = sc->ops->repair(sc);
trace_xrep_done(XFS_I(file_inode(sc->file)), sc->sm, error);
switch (error) {
case 0:
/*
* Repair succeeded. Commit the fixes and perform a second
* scrub so that we can tell userspace if we fixed the problem.
*/
sc->sm->sm_flags &= ~XFS_SCRUB_FLAGS_OUT;
sc->flags |= XREP_ALREADY_FIXED;
return -EAGAIN;
case -EDEADLOCK:
case -EAGAIN:
/* Tell the caller to try again having grabbed all the locks. */
if (!(sc->flags & XCHK_TRY_HARDER)) {
sc->flags |= XCHK_TRY_HARDER;
return -EAGAIN;
}
/*
* We tried harder but still couldn't grab all the resources
* we needed to fix it. The corruption has not been fixed,
* so report back to userspace.
*/
return -EFSCORRUPTED;
default:
return error;
}
}
/*
* Complain about unfixable problems in the filesystem. We don't log
* corruptions when IFLAG_REPAIR wasn't set on the assumption that the driver
* program is xfs_scrub, which will call back with IFLAG_REPAIR set if the
* administrator isn't running xfs_scrub in no-repairs mode.
*
* Use this helper function because _ratelimited silently declares a static
* structure to track rate limiting information.
*/
void
xrep_failure(
struct xfs_mount *mp)
{
xfs_alert_ratelimited(mp,
"Corruption not fixed during online repair. Unmount and run xfs_repair.");
}
/*
* Repair probe -- userspace uses this to probe if we're willing to repair a
* given mountpoint.
*/
int
xrep_probe(
struct xfs_scrub *sc)
{
int error = 0;
if (xchk_should_terminate(sc, &error))
return error;
return 0;
}
/*
* Roll a transaction, keeping the AG headers locked and reinitializing
* the btree cursors.
*/
int
xrep_roll_ag_trans(
struct xfs_scrub *sc)
{
int error;
/* Keep the AG header buffers locked so we can keep going. */
if (sc->sa.agi_bp)
xfs_trans_bhold(sc->tp, sc->sa.agi_bp);
if (sc->sa.agf_bp)
xfs_trans_bhold(sc->tp, sc->sa.agf_bp);
if (sc->sa.agfl_bp)
xfs_trans_bhold(sc->tp, sc->sa.agfl_bp);
/*
* Roll the transaction. We still own the buffer and the buffer lock
* regardless of whether or not the roll succeeds. If the roll fails,
* the buffers will be released during teardown on our way out of the
* kernel. If it succeeds, we join them to the new transaction and
* move on.
*/
error = xfs_trans_roll(&sc->tp);
if (error)
return error;
/* Join AG headers to the new transaction. */
if (sc->sa.agi_bp)
xfs_trans_bjoin(sc->tp, sc->sa.agi_bp);
if (sc->sa.agf_bp)
xfs_trans_bjoin(sc->tp, sc->sa.agf_bp);
if (sc->sa.agfl_bp)
xfs_trans_bjoin(sc->tp, sc->sa.agfl_bp);
return 0;
}
/*
* Does the given AG have enough space to rebuild a btree? Neither AG
* reservation can be critical, and we must have enough space (factoring
* in AG reservations) to construct a whole btree.
*/
bool
xrep_ag_has_space(
struct xfs_perag *pag,
xfs_extlen_t nr_blocks,
enum xfs_ag_resv_type type)
{
return !xfs_ag_resv_critical(pag, XFS_AG_RESV_RMAPBT) &&
!xfs_ag_resv_critical(pag, XFS_AG_RESV_METADATA) &&
pag->pagf_freeblks > xfs_ag_resv_needed(pag, type) + nr_blocks;
}
/*
* Figure out how many blocks to reserve for an AG repair. We calculate the
* worst case estimate for the number of blocks we'd need to rebuild one of
* any type of per-AG btree.
*/
xfs_extlen_t
xrep_calc_ag_resblks(
struct xfs_scrub *sc)
{
struct xfs_mount *mp = sc->mp;
struct xfs_scrub_metadata *sm = sc->sm;
struct xfs_perag *pag;
struct xfs_buf *bp;
xfs_agino_t icount = NULLAGINO;
xfs_extlen_t aglen = NULLAGBLOCK;
xfs_extlen_t usedlen;
xfs_extlen_t freelen;
xfs_extlen_t bnobt_sz;
xfs_extlen_t inobt_sz;
xfs_extlen_t rmapbt_sz;
xfs_extlen_t refcbt_sz;
int error;
if (!(sm->sm_flags & XFS_SCRUB_IFLAG_REPAIR))
return 0;
pag = xfs_perag_get(mp, sm->sm_agno);
if (pag->pagi_init) {
/* Use in-core icount if possible. */
icount = pag->pagi_count;
} else {
/* Try to get the actual counters from disk. */
error = xfs_ialloc_read_agi(mp, NULL, sm->sm_agno, &bp);
if (!error) {
icount = pag->pagi_count;
xfs_buf_relse(bp);
}
}
/* Now grab the block counters from the AGF. */
error = xfs_alloc_read_agf(mp, NULL, sm->sm_agno, 0, &bp);
if (error) {
aglen = xfs_ag_block_count(mp, sm->sm_agno);
freelen = aglen;
usedlen = aglen;
} else {
struct xfs_agf *agf = bp->b_addr;
aglen = be32_to_cpu(agf->agf_length);
freelen = be32_to_cpu(agf->agf_freeblks);
usedlen = aglen - freelen;
xfs_buf_relse(bp);
}
xfs_perag_put(pag);
/* If the icount is impossible, make some worst-case assumptions. */
if (icount == NULLAGINO ||
!xfs_verify_agino(mp, sm->sm_agno, icount)) {
xfs_agino_t first, last;
xfs_agino_range(mp, sm->sm_agno, &first, &last);
icount = last - first + 1;
}
/* If the block counts are impossible, make worst-case assumptions. */
if (aglen == NULLAGBLOCK ||
aglen != xfs_ag_block_count(mp, sm->sm_agno) ||
freelen >= aglen) {
aglen = xfs_ag_block_count(mp, sm->sm_agno);
freelen = aglen;
usedlen = aglen;
}
trace_xrep_calc_ag_resblks(mp, sm->sm_agno, icount, aglen,
freelen, usedlen);
/*
* Figure out how many blocks we'd need worst case to rebuild
* each type of btree. Note that we can only rebuild the
* bnobt/cntbt or inobt/finobt as pairs.
*/
bnobt_sz = 2 * xfs_allocbt_calc_size(mp, freelen);
if (xfs_has_sparseinodes(mp))
inobt_sz = xfs_iallocbt_calc_size(mp, icount /
XFS_INODES_PER_HOLEMASK_BIT);
else
inobt_sz = xfs_iallocbt_calc_size(mp, icount /
XFS_INODES_PER_CHUNK);
if (xfs_has_finobt(mp))
inobt_sz *= 2;
if (xfs_has_reflink(mp))
refcbt_sz = xfs_refcountbt_calc_size(mp, usedlen);
else
refcbt_sz = 0;
if (xfs_has_rmapbt(mp)) {
/*
* Guess how many blocks we need to rebuild the rmapbt.
* For non-reflink filesystems we can't have more records than
* used blocks. However, with reflink it's possible to have
* more than one rmap record per AG block. We don't know how
* many rmaps there could be in the AG, so we start off with
* what we hope is an generous over-estimation.
*/
if (xfs_has_reflink(mp))
rmapbt_sz = xfs_rmapbt_calc_size(mp,
(unsigned long long)aglen * 2);
else
rmapbt_sz = xfs_rmapbt_calc_size(mp, usedlen);
} else {
rmapbt_sz = 0;
}
trace_xrep_calc_ag_resblks_btsize(mp, sm->sm_agno, bnobt_sz,
inobt_sz, rmapbt_sz, refcbt_sz);
return max(max(bnobt_sz, inobt_sz), max(rmapbt_sz, refcbt_sz));
}
/* Allocate a block in an AG. */
int
xrep_alloc_ag_block(
struct xfs_scrub *sc,
const struct xfs_owner_info *oinfo,
xfs_fsblock_t *fsbno,
enum xfs_ag_resv_type resv)
{
struct xfs_alloc_arg args = {0};
xfs_agblock_t bno;
int error;
switch (resv) {
case XFS_AG_RESV_AGFL:
case XFS_AG_RESV_RMAPBT:
error = xfs_alloc_get_freelist(sc->tp, sc->sa.agf_bp, &bno, 1);
if (error)
return error;
if (bno == NULLAGBLOCK)
return -ENOSPC;
xfs_extent_busy_reuse(sc->mp, sc->sa.pag, bno,
1, false);
*fsbno = XFS_AGB_TO_FSB(sc->mp, sc->sa.pag->pag_agno, bno);
if (resv == XFS_AG_RESV_RMAPBT)
xfs_ag_resv_rmapbt_alloc(sc->mp, sc->sa.pag->pag_agno);
return 0;
default:
break;
}
args.tp = sc->tp;
args.mp = sc->mp;
args.oinfo = *oinfo;
args.fsbno = XFS_AGB_TO_FSB(args.mp, sc->sa.pag->pag_agno, 0);
args.minlen = 1;
args.maxlen = 1;
args.prod = 1;
args.type = XFS_ALLOCTYPE_THIS_AG;
args.resv = resv;
error = xfs_alloc_vextent(&args);
if (error)
return error;
if (args.fsbno == NULLFSBLOCK)
return -ENOSPC;
ASSERT(args.len == 1);
*fsbno = args.fsbno;
return 0;
}
/* Initialize a new AG btree root block with zero entries. */
int
xrep_init_btblock(
struct xfs_scrub *sc,
xfs_fsblock_t fsb,
struct xfs_buf **bpp,
xfs_btnum_t btnum,
const struct xfs_buf_ops *ops)
{
struct xfs_trans *tp = sc->tp;
struct xfs_mount *mp = sc->mp;
struct xfs_buf *bp;
int error;
trace_xrep_init_btblock(mp, XFS_FSB_TO_AGNO(mp, fsb),
XFS_FSB_TO_AGBNO(mp, fsb), btnum);
ASSERT(XFS_FSB_TO_AGNO(mp, fsb) == sc->sa.pag->pag_agno);
error = xfs_trans_get_buf(tp, mp->m_ddev_targp,
XFS_FSB_TO_DADDR(mp, fsb), XFS_FSB_TO_BB(mp, 1), 0,
&bp);
if (error)
return error;
xfs_buf_zero(bp, 0, BBTOB(bp->b_length));
xfs_btree_init_block(mp, bp, btnum, 0, 0, sc->sa.pag->pag_agno);
xfs_trans_buf_set_type(tp, bp, XFS_BLFT_BTREE_BUF);
xfs_trans_log_buf(tp, bp, 0, BBTOB(bp->b_length) - 1);
bp->b_ops = ops;
*bpp = bp;
return 0;
}
/*
* Reconstructing per-AG Btrees
*
* When a space btree is corrupt, we don't bother trying to fix it. Instead,
* we scan secondary space metadata to derive the records that should be in
* the damaged btree, initialize a fresh btree root, and insert the records.
* Note that for rebuilding the rmapbt we scan all the primary data to
* generate the new records.
*
* However, that leaves the matter of removing all the metadata describing the
* old broken structure. For primary metadata we use the rmap data to collect
* every extent with a matching rmap owner (bitmap); we then iterate all other
* metadata structures with the same rmap owner to collect the extents that
* cannot be removed (sublist). We then subtract sublist from bitmap to
* derive the blocks that were used by the old btree. These blocks can be
* reaped.
*
* For rmapbt reconstructions we must use different tactics for extent
* collection. First we iterate all primary metadata (this excludes the old
* rmapbt, obviously) to generate new rmap records. The gaps in the rmap
* records are collected as bitmap. The bnobt records are collected as
* sublist. As with the other btrees we subtract sublist from bitmap, and the
* result (since the rmapbt lives in the free space) are the blocks from the
* old rmapbt.
*
* Disposal of Blocks from Old per-AG Btrees
*
* Now that we've constructed a new btree to replace the damaged one, we want
* to dispose of the blocks that (we think) the old btree was using.
* Previously, we used the rmapbt to collect the extents (bitmap) with the
* rmap owner corresponding to the tree we rebuilt, collected extents for any
* blocks with the same rmap owner that are owned by another data structure
* (sublist), and subtracted sublist from bitmap. In theory the extents
* remaining in bitmap are the old btree's blocks.
*
* Unfortunately, it's possible that the btree was crosslinked with other
* blocks on disk. The rmap data can tell us if there are multiple owners, so
* if the rmapbt says there is an owner of this block other than @oinfo, then
* the block is crosslinked. Remove the reverse mapping and continue.
*
* If there is one rmap record, we can free the block, which removes the
* reverse mapping but doesn't add the block to the free space. Our repair
* strategy is to hope the other metadata objects crosslinked on this block
* will be rebuilt (atop different blocks), thereby removing all the cross
* links.
*
* If there are no rmap records at all, we also free the block. If the btree
* being rebuilt lives in the free space (bnobt/cntbt/rmapbt) then there isn't
* supposed to be a rmap record and everything is ok. For other btrees there
* had to have been an rmap entry for the block to have ended up on @bitmap,
* so if it's gone now there's something wrong and the fs will shut down.
*
* Note: If there are multiple rmap records with only the same rmap owner as
* the btree we're trying to rebuild and the block is indeed owned by another
* data structure with the same rmap owner, then the block will be in sublist
* and therefore doesn't need disposal. If there are multiple rmap records
* with only the same rmap owner but the block is not owned by something with
* the same rmap owner, the block will be freed.
*
* The caller is responsible for locking the AG headers for the entire rebuild
* operation so that nothing else can sneak in and change the AG state while
* we're not looking. We also assume that the caller already invalidated any
* buffers associated with @bitmap.
*/
/*
* Invalidate buffers for per-AG btree blocks we're dumping. This function
* is not intended for use with file data repairs; we have bunmapi for that.
*/
int
xrep_invalidate_blocks(
struct xfs_scrub *sc,
struct xbitmap *bitmap)
{
struct xbitmap_range *bmr;
struct xbitmap_range *n;
struct xfs_buf *bp;
xfs_fsblock_t fsbno;
/*
* For each block in each extent, see if there's an incore buffer for
* exactly that block; if so, invalidate it. The buffer cache only
* lets us look for one buffer at a time, so we have to look one block
* at a time. Avoid invalidating AG headers and post-EOFS blocks
* because we never own those; and if we can't TRYLOCK the buffer we
* assume it's owned by someone else.
*/
for_each_xbitmap_block(fsbno, bmr, n, bitmap) {
/* Skip AG headers and post-EOFS blocks */
if (!xfs_verify_fsbno(sc->mp, fsbno))
continue;
bp = xfs_buf_incore(sc->mp->m_ddev_targp,
XFS_FSB_TO_DADDR(sc->mp, fsbno),
XFS_FSB_TO_BB(sc->mp, 1), XBF_TRYLOCK);
if (bp) {
xfs_trans_bjoin(sc->tp, bp);
xfs_trans_binval(sc->tp, bp);
}
}
return 0;
}
/* Ensure the freelist is the correct size. */
int
xrep_fix_freelist(
struct xfs_scrub *sc,
bool can_shrink)
{
struct xfs_alloc_arg args = {0};
args.mp = sc->mp;
args.tp = sc->tp;
args.agno = sc->sa.pag->pag_agno;
args.alignment = 1;
args.pag = sc->sa.pag;
return xfs_alloc_fix_freelist(&args,
can_shrink ? 0 : XFS_ALLOC_FLAG_NOSHRINK);
}
/*
* Put a block back on the AGFL.
*/
STATIC int
xrep_put_freelist(
struct xfs_scrub *sc,
xfs_agblock_t agbno)
{
int error;
/* Make sure there's space on the freelist. */
error = xrep_fix_freelist(sc, true);
if (error)
return error;
/*
* Since we're "freeing" a lost block onto the AGFL, we have to
* create an rmap for the block prior to merging it or else other
* parts will break.
*/
error = xfs_rmap_alloc(sc->tp, sc->sa.agf_bp, sc->sa.pag, agbno, 1,
&XFS_RMAP_OINFO_AG);
if (error)
return error;
/* Put the block on the AGFL. */
error = xfs_alloc_put_freelist(sc->tp, sc->sa.agf_bp, sc->sa.agfl_bp,
agbno, 0);
if (error)
return error;
xfs_extent_busy_insert(sc->tp, sc->sa.pag, agbno, 1,
XFS_EXTENT_BUSY_SKIP_DISCARD);
return 0;
}
/* Dispose of a single block. */
STATIC int
xrep_reap_block(
struct xfs_scrub *sc,
xfs_fsblock_t fsbno,
const struct xfs_owner_info *oinfo,
enum xfs_ag_resv_type resv)
{
struct xfs_btree_cur *cur;
struct xfs_buf *agf_bp = NULL;
xfs_agnumber_t agno;
xfs_agblock_t agbno;
bool has_other_rmap;
int error;
agno = XFS_FSB_TO_AGNO(sc->mp, fsbno);
agbno = XFS_FSB_TO_AGBNO(sc->mp, fsbno);
/*
* If we are repairing per-inode metadata, we need to read in the AGF
* buffer. Otherwise, we're repairing a per-AG structure, so reuse
* the AGF buffer that the setup functions already grabbed.
*/
if (sc->ip) {
error = xfs_alloc_read_agf(sc->mp, sc->tp, agno, 0, &agf_bp);
if (error)
return error;
} else {
agf_bp = sc->sa.agf_bp;
}
cur = xfs_rmapbt_init_cursor(sc->mp, sc->tp, agf_bp, sc->sa.pag);
/* Can we find any other rmappings? */
error = xfs_rmap_has_other_keys(cur, agbno, 1, oinfo, &has_other_rmap);
xfs_btree_del_cursor(cur, error);
if (error)
goto out_free;
/*
* If there are other rmappings, this block is cross linked and must
* not be freed. Remove the reverse mapping and move on. Otherwise,
* we were the only owner of the block, so free the extent, which will
* also remove the rmap.
*
* XXX: XFS doesn't support detecting the case where a single block
* metadata structure is crosslinked with a multi-block structure
* because the buffer cache doesn't detect aliasing problems, so we
* can't fix 100% of crosslinking problems (yet). The verifiers will
* blow on writeout, the filesystem will shut down, and the admin gets
* to run xfs_repair.
*/
if (has_other_rmap)
error = xfs_rmap_free(sc->tp, agf_bp, sc->sa.pag, agbno,
1, oinfo);
else if (resv == XFS_AG_RESV_AGFL)
error = xrep_put_freelist(sc, agbno);
else
error = xfs_free_extent(sc->tp, fsbno, 1, oinfo, resv);
if (agf_bp != sc->sa.agf_bp)
xfs_trans_brelse(sc->tp, agf_bp);
if (error)
return error;
if (sc->ip)
return xfs_trans_roll_inode(&sc->tp, sc->ip);
return xrep_roll_ag_trans(sc);
out_free:
if (agf_bp != sc->sa.agf_bp)
xfs_trans_brelse(sc->tp, agf_bp);
return error;
}
/* Dispose of every block of every extent in the bitmap. */
int
xrep_reap_extents(
struct xfs_scrub *sc,
struct xbitmap *bitmap,
const struct xfs_owner_info *oinfo,
enum xfs_ag_resv_type type)
{
struct xbitmap_range *bmr;
struct xbitmap_range *n;
xfs_fsblock_t fsbno;
int error = 0;
ASSERT(xfs_has_rmapbt(sc->mp));
for_each_xbitmap_block(fsbno, bmr, n, bitmap) {
ASSERT(sc->ip != NULL ||
XFS_FSB_TO_AGNO(sc->mp, fsbno) == sc->sa.pag->pag_agno);
trace_xrep_dispose_btree_extent(sc->mp,
XFS_FSB_TO_AGNO(sc->mp, fsbno),
XFS_FSB_TO_AGBNO(sc->mp, fsbno), 1);
error = xrep_reap_block(sc, fsbno, oinfo, type);
if (error)
break;
}
return error;
}
/*
* Finding per-AG Btree Roots for AGF/AGI Reconstruction
*
* If the AGF or AGI become slightly corrupted, it may be necessary to rebuild
* the AG headers by using the rmap data to rummage through the AG looking for
* btree roots. This is not guaranteed to work if the AG is heavily damaged
* or the rmap data are corrupt.
*
* Callers of xrep_find_ag_btree_roots must lock the AGF and AGFL
* buffers if the AGF is being rebuilt; or the AGF and AGI buffers if the
* AGI is being rebuilt. It must maintain these locks until it's safe for
* other threads to change the btrees' shapes. The caller provides
* information about the btrees to look for by passing in an array of
* xrep_find_ag_btree with the (rmap owner, buf_ops, magic) fields set.
* The (root, height) fields will be set on return if anything is found. The
* last element of the array should have a NULL buf_ops to mark the end of the
* array.
*
* For every rmapbt record matching any of the rmap owners in btree_info,
* read each block referenced by the rmap record. If the block is a btree
* block from this filesystem matching any of the magic numbers and has a
* level higher than what we've already seen, remember the block and the
* height of the tree required to have such a block. When the call completes,
* we return the highest block we've found for each btree description; those
* should be the roots.
*/
struct xrep_findroot {
struct xfs_scrub *sc;
struct xfs_buf *agfl_bp;
struct xfs_agf *agf;
struct xrep_find_ag_btree *btree_info;
};
/* See if our block is in the AGFL. */
STATIC int
xrep_findroot_agfl_walk(
struct xfs_mount *mp,
xfs_agblock_t bno,
void *priv)
{
xfs_agblock_t *agbno = priv;
return (*agbno == bno) ? -ECANCELED : 0;
}
/* Does this block match the btree information passed in? */
STATIC int
xrep_findroot_block(
struct xrep_findroot *ri,
struct xrep_find_ag_btree *fab,
uint64_t owner,
xfs_agblock_t agbno,
bool *done_with_block)
{
struct xfs_mount *mp = ri->sc->mp;
struct xfs_buf *bp;
struct xfs_btree_block *btblock;
xfs_daddr_t daddr;
int block_level;
int error = 0;
daddr = XFS_AGB_TO_DADDR(mp, ri->sc->sa.pag->pag_agno, agbno);
/*
* Blocks in the AGFL have stale contents that might just happen to
* have a matching magic and uuid. We don't want to pull these blocks
* in as part of a tree root, so we have to filter out the AGFL stuff
* here. If the AGFL looks insane we'll just refuse to repair.
*/
if (owner == XFS_RMAP_OWN_AG) {
error = xfs_agfl_walk(mp, ri->agf, ri->agfl_bp,
xrep_findroot_agfl_walk, &agbno);
if (error == -ECANCELED)
return 0;
if (error)
return error;
}
/*
* Read the buffer into memory so that we can see if it's a match for
* our btree type. We have no clue if it is beforehand, and we want to
* avoid xfs_trans_read_buf's behavior of dumping the DONE state (which
* will cause needless disk reads in subsequent calls to this function)
* and logging metadata verifier failures.
*
* Therefore, pass in NULL buffer ops. If the buffer was already in
* memory from some other caller it will already have b_ops assigned.
* If it was in memory from a previous unsuccessful findroot_block
* call, the buffer won't have b_ops but it should be clean and ready
* for us to try to verify if the read call succeeds. The same applies
* if the buffer wasn't in memory at all.
*
* Note: If we never match a btree type with this buffer, it will be
* left in memory with NULL b_ops. This shouldn't be a problem unless
* the buffer gets written.
*/
error = xfs_trans_read_buf(mp, ri->sc->tp, mp->m_ddev_targp, daddr,
mp->m_bsize, 0, &bp, NULL);
if (error)
return error;
/* Ensure the block magic matches the btree type we're looking for. */
btblock = XFS_BUF_TO_BLOCK(bp);
ASSERT(fab->buf_ops->magic[1] != 0);
if (btblock->bb_magic != fab->buf_ops->magic[1])
goto out;
/*
* If the buffer already has ops applied and they're not the ones for
* this btree type, we know this block doesn't match the btree and we
* can bail out.
*
* If the buffer ops match ours, someone else has already validated
* the block for us, so we can move on to checking if this is a root
* block candidate.
*
* If the buffer does not have ops, nobody has successfully validated
* the contents and the buffer cannot be dirty. If the magic, uuid,
* and structure match this btree type then we'll move on to checking
* if it's a root block candidate. If there is no match, bail out.
*/
if (bp->b_ops) {
if (bp->b_ops != fab->buf_ops)
goto out;
} else {
ASSERT(!xfs_trans_buf_is_dirty(bp));
if (!uuid_equal(&btblock->bb_u.s.bb_uuid,
&mp->m_sb.sb_meta_uuid))
goto out;
/*
* Read verifiers can reference b_ops, so we set the pointer
* here. If the verifier fails we'll reset the buffer state
* to what it was before we touched the buffer.
*/
bp->b_ops = fab->buf_ops;
fab->buf_ops->verify_read(bp);
if (bp->b_error) {
bp->b_ops = NULL;
bp->b_error = 0;
goto out;
}
/*
* Some read verifiers will (re)set b_ops, so we must be
* careful not to change b_ops after running the verifier.
*/
}
/*
* This block passes the magic/uuid and verifier tests for this btree
* type. We don't need the caller to try the other tree types.
*/
*done_with_block = true;
/*
* Compare this btree block's level to the height of the current
* candidate root block.
*
* If the level matches the root we found previously, throw away both
* blocks because there can't be two candidate roots.
*
* If level is lower in the tree than the root we found previously,
* ignore this block.
*/
block_level = xfs_btree_get_level(btblock);
if (block_level + 1 == fab->height) {
fab->root = NULLAGBLOCK;
goto out;
} else if (block_level < fab->height) {
goto out;
}
/*
* This is the highest block in the tree that we've found so far.
* Update the btree height to reflect what we've learned from this
* block.
*/
fab->height = block_level + 1;
/*
* If this block doesn't have sibling pointers, then it's the new root
* block candidate. Otherwise, the root will be found farther up the
* tree.
*/
if (btblock->bb_u.s.bb_leftsib == cpu_to_be32(NULLAGBLOCK) &&
btblock->bb_u.s.bb_rightsib == cpu_to_be32(NULLAGBLOCK))
fab->root = agbno;
else
fab->root = NULLAGBLOCK;
trace_xrep_findroot_block(mp, ri->sc->sa.pag->pag_agno, agbno,
be32_to_cpu(btblock->bb_magic), fab->height - 1);
out:
xfs_trans_brelse(ri->sc->tp, bp);
return error;
}
/*
* Do any of the blocks in this rmap record match one of the btrees we're
* looking for?
*/
STATIC int
xrep_findroot_rmap(
struct xfs_btree_cur *cur,
const struct xfs_rmap_irec *rec,
void *priv)
{
struct xrep_findroot *ri = priv;
struct xrep_find_ag_btree *fab;
xfs_agblock_t b;
bool done;
int error = 0;
/* Ignore anything that isn't AG metadata. */
if (!XFS_RMAP_NON_INODE_OWNER(rec->rm_owner))
return 0;
/* Otherwise scan each block + btree type. */
for (b = 0; b < rec->rm_blockcount; b++) {
done = false;
for (fab = ri->btree_info; fab->buf_ops; fab++) {
if (rec->rm_owner != fab->rmap_owner)
continue;
error = xrep_findroot_block(ri, fab,
rec->rm_owner, rec->rm_startblock + b,
&done);
if (error)
return error;
if (done)
break;
}
}
return 0;
}
/* Find the roots of the per-AG btrees described in btree_info. */
int
xrep_find_ag_btree_roots(
struct xfs_scrub *sc,
struct xfs_buf *agf_bp,
struct xrep_find_ag_btree *btree_info,
struct xfs_buf *agfl_bp)
{
struct xfs_mount *mp = sc->mp;
struct xrep_findroot ri;
struct xrep_find_ag_btree *fab;
struct xfs_btree_cur *cur;
int error;
ASSERT(xfs_buf_islocked(agf_bp));
ASSERT(agfl_bp == NULL || xfs_buf_islocked(agfl_bp));
ri.sc = sc;
ri.btree_info = btree_info;
ri.agf = agf_bp->b_addr;
ri.agfl_bp = agfl_bp;
for (fab = btree_info; fab->buf_ops; fab++) {
ASSERT(agfl_bp || fab->rmap_owner != XFS_RMAP_OWN_AG);
ASSERT(XFS_RMAP_NON_INODE_OWNER(fab->rmap_owner));
fab->root = NULLAGBLOCK;
fab->height = 0;
}
cur = xfs_rmapbt_init_cursor(mp, sc->tp, agf_bp, sc->sa.pag);
error = xfs_rmap_query_all(cur, xrep_findroot_rmap, &ri);
xfs_btree_del_cursor(cur, error);
return error;
}
/* Force a quotacheck the next time we mount. */
void
xrep_force_quotacheck(
struct xfs_scrub *sc,
xfs_dqtype_t type)
{
uint flag;
flag = xfs_quota_chkd_flag(type);
if (!(flag & sc->mp->m_qflags))
return;
sc->mp->m_qflags &= ~flag;
spin_lock(&sc->mp->m_sb_lock);
sc->mp->m_sb.sb_qflags &= ~flag;
spin_unlock(&sc->mp->m_sb_lock);
xfs_log_sb(sc->tp);
}
/*
* Attach dquots to this inode, or schedule quotacheck to fix them.
*
* This function ensures that the appropriate dquots are attached to an inode.
* We cannot allow the dquot code to allocate an on-disk dquot block here
* because we're already in transaction context with the inode locked. The
* on-disk dquot should already exist anyway. If the quota code signals
* corruption or missing quota information, schedule quotacheck, which will
* repair corruptions in the quota metadata.
*/
int
xrep_ino_dqattach(
struct xfs_scrub *sc)
{
int error;
error = xfs_qm_dqattach_locked(sc->ip, false);
switch (error) {
case -EFSBADCRC:
case -EFSCORRUPTED:
case -ENOENT:
xfs_err_ratelimited(sc->mp,
"inode %llu repair encountered quota error %d, quotacheck forced.",
(unsigned long long)sc->ip->i_ino, error);
if (XFS_IS_UQUOTA_ON(sc->mp) && !sc->ip->i_udquot)
xrep_force_quotacheck(sc, XFS_DQTYPE_USER);
if (XFS_IS_GQUOTA_ON(sc->mp) && !sc->ip->i_gdquot)
xrep_force_quotacheck(sc, XFS_DQTYPE_GROUP);
if (XFS_IS_PQUOTA_ON(sc->mp) && !sc->ip->i_pdquot)
xrep_force_quotacheck(sc, XFS_DQTYPE_PROJ);
fallthrough;
case -ESRCH:
error = 0;
break;
default:
break;
}
return error;
}