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-rw-r--r--fs/xfs/scrub/common.c574
1 files changed, 574 insertions, 0 deletions
diff --git a/fs/xfs/scrub/common.c b/fs/xfs/scrub/common.c
new file mode 100644
index 000000000000..ac95fe911d96
--- /dev/null
+++ b/fs/xfs/scrub/common.c
@@ -0,0 +1,574 @@
+/*
+ * Copyright (C) 2017 Oracle. All Rights Reserved.
+ *
+ * Author: Darrick J. Wong <darrick.wong@oracle.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it would be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+#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_defer.h"
+#include "xfs_btree.h"
+#include "xfs_bit.h"
+#include "xfs_log_format.h"
+#include "xfs_trans.h"
+#include "xfs_sb.h"
+#include "xfs_inode.h"
+#include "xfs_icache.h"
+#include "xfs_itable.h"
+#include "xfs_alloc.h"
+#include "xfs_alloc_btree.h"
+#include "xfs_bmap.h"
+#include "xfs_bmap_btree.h"
+#include "xfs_ialloc.h"
+#include "xfs_ialloc_btree.h"
+#include "xfs_refcount.h"
+#include "xfs_refcount_btree.h"
+#include "xfs_rmap.h"
+#include "xfs_rmap_btree.h"
+#include "xfs_log.h"
+#include "xfs_trans_priv.h"
+#include "scrub/xfs_scrub.h"
+#include "scrub/scrub.h"
+#include "scrub/common.h"
+#include "scrub/trace.h"
+#include "scrub/btree.h"
+
+/* Common code for the metadata scrubbers. */
+
+/*
+ * Handling operational errors.
+ *
+ * The *_process_error() family of functions are used to process error return
+ * codes from functions called as part of a scrub operation.
+ *
+ * If there's no error, we return true to tell the caller that it's ok
+ * to move on to the next check in its list.
+ *
+ * For non-verifier errors (e.g. ENOMEM) we return false to tell the
+ * caller that something bad happened, and we preserve *error so that
+ * the caller can return the *error up the stack to userspace.
+ *
+ * Verifier errors (EFSBADCRC/EFSCORRUPTED) are recorded by setting
+ * OFLAG_CORRUPT in sm_flags and the *error is cleared. In other words,
+ * we track verifier errors (and failed scrub checks) via OFLAG_CORRUPT,
+ * not via return codes. We return false to tell the caller that
+ * something bad happened. Since the error has been cleared, the caller
+ * will (presumably) return that zero and scrubbing will move on to
+ * whatever's next.
+ *
+ * ftrace can be used to record the precise metadata location and the
+ * approximate code location of the failed operation.
+ */
+
+/* Check for operational errors. */
+bool
+xfs_scrub_process_error(
+ struct xfs_scrub_context *sc,
+ xfs_agnumber_t agno,
+ xfs_agblock_t bno,
+ int *error)
+{
+ switch (*error) {
+ case 0:
+ return true;
+ case -EDEADLOCK:
+ /* Used to restart an op with deadlock avoidance. */
+ trace_xfs_scrub_deadlock_retry(sc->ip, sc->sm, *error);
+ break;
+ case -EFSBADCRC:
+ case -EFSCORRUPTED:
+ /* Note the badness but don't abort. */
+ sc->sm->sm_flags |= XFS_SCRUB_OFLAG_CORRUPT;
+ *error = 0;
+ /* fall through */
+ default:
+ trace_xfs_scrub_op_error(sc, agno, bno, *error,
+ __return_address);
+ break;
+ }
+ return false;
+}
+
+/* Check for operational errors for a file offset. */
+bool
+xfs_scrub_fblock_process_error(
+ struct xfs_scrub_context *sc,
+ int whichfork,
+ xfs_fileoff_t offset,
+ int *error)
+{
+ switch (*error) {
+ case 0:
+ return true;
+ case -EDEADLOCK:
+ /* Used to restart an op with deadlock avoidance. */
+ trace_xfs_scrub_deadlock_retry(sc->ip, sc->sm, *error);
+ break;
+ case -EFSBADCRC:
+ case -EFSCORRUPTED:
+ /* Note the badness but don't abort. */
+ sc->sm->sm_flags |= XFS_SCRUB_OFLAG_CORRUPT;
+ *error = 0;
+ /* fall through */
+ default:
+ trace_xfs_scrub_file_op_error(sc, whichfork, offset, *error,
+ __return_address);
+ break;
+ }
+ return false;
+}
+
+/*
+ * Handling scrub corruption/optimization/warning checks.
+ *
+ * The *_set_{corrupt,preen,warning}() family of functions are used to
+ * record the presence of metadata that is incorrect (corrupt), could be
+ * optimized somehow (preen), or should be flagged for administrative
+ * review but is not incorrect (warn).
+ *
+ * ftrace can be used to record the precise metadata location and
+ * approximate code location of the failed check.
+ */
+
+/* Record a block which could be optimized. */
+void
+xfs_scrub_block_set_preen(
+ struct xfs_scrub_context *sc,
+ struct xfs_buf *bp)
+{
+ sc->sm->sm_flags |= XFS_SCRUB_OFLAG_PREEN;
+ trace_xfs_scrub_block_preen(sc, bp->b_bn, __return_address);
+}
+
+/*
+ * Record an inode which could be optimized. The trace data will
+ * include the block given by bp if bp is given; otherwise it will use
+ * the block location of the inode record itself.
+ */
+void
+xfs_scrub_ino_set_preen(
+ struct xfs_scrub_context *sc,
+ xfs_ino_t ino,
+ struct xfs_buf *bp)
+{
+ sc->sm->sm_flags |= XFS_SCRUB_OFLAG_PREEN;
+ trace_xfs_scrub_ino_preen(sc, ino, bp ? bp->b_bn : 0,
+ __return_address);
+}
+
+/* Record a corrupt block. */
+void
+xfs_scrub_block_set_corrupt(
+ struct xfs_scrub_context *sc,
+ struct xfs_buf *bp)
+{
+ sc->sm->sm_flags |= XFS_SCRUB_OFLAG_CORRUPT;
+ trace_xfs_scrub_block_error(sc, bp->b_bn, __return_address);
+}
+
+/*
+ * Record a corrupt inode. The trace data will include the block given
+ * by bp if bp is given; otherwise it will use the block location of the
+ * inode record itself.
+ */
+void
+xfs_scrub_ino_set_corrupt(
+ struct xfs_scrub_context *sc,
+ xfs_ino_t ino,
+ struct xfs_buf *bp)
+{
+ sc->sm->sm_flags |= XFS_SCRUB_OFLAG_CORRUPT;
+ trace_xfs_scrub_ino_error(sc, ino, bp ? bp->b_bn : 0, __return_address);
+}
+
+/* Record corruption in a block indexed by a file fork. */
+void
+xfs_scrub_fblock_set_corrupt(
+ struct xfs_scrub_context *sc,
+ int whichfork,
+ xfs_fileoff_t offset)
+{
+ sc->sm->sm_flags |= XFS_SCRUB_OFLAG_CORRUPT;
+ trace_xfs_scrub_fblock_error(sc, whichfork, offset, __return_address);
+}
+
+/*
+ * Warn about inodes that need administrative review but is not
+ * incorrect.
+ */
+void
+xfs_scrub_ino_set_warning(
+ struct xfs_scrub_context *sc,
+ xfs_ino_t ino,
+ struct xfs_buf *bp)
+{
+ sc->sm->sm_flags |= XFS_SCRUB_OFLAG_WARNING;
+ trace_xfs_scrub_ino_warning(sc, ino, bp ? bp->b_bn : 0,
+ __return_address);
+}
+
+/* Warn about a block indexed by a file fork that needs review. */
+void
+xfs_scrub_fblock_set_warning(
+ struct xfs_scrub_context *sc,
+ int whichfork,
+ xfs_fileoff_t offset)
+{
+ sc->sm->sm_flags |= XFS_SCRUB_OFLAG_WARNING;
+ trace_xfs_scrub_fblock_warning(sc, whichfork, offset, __return_address);
+}
+
+/* Signal an incomplete scrub. */
+void
+xfs_scrub_set_incomplete(
+ struct xfs_scrub_context *sc)
+{
+ sc->sm->sm_flags |= XFS_SCRUB_OFLAG_INCOMPLETE;
+ trace_xfs_scrub_incomplete(sc, __return_address);
+}
+
+/*
+ * AG scrubbing
+ *
+ * These helpers facilitate locking an allocation group's header
+ * buffers, setting up cursors for all btrees that are present, and
+ * cleaning everything up once we're through.
+ */
+
+/* Decide if we want to return an AG header read failure. */
+static inline bool
+want_ag_read_header_failure(
+ struct xfs_scrub_context *sc,
+ unsigned int type)
+{
+ /* Return all AG header read failures when scanning btrees. */
+ if (sc->sm->sm_type != XFS_SCRUB_TYPE_AGF &&
+ sc->sm->sm_type != XFS_SCRUB_TYPE_AGFL &&
+ sc->sm->sm_type != XFS_SCRUB_TYPE_AGI)
+ return true;
+ /*
+ * If we're scanning a given type of AG header, we only want to
+ * see read failures from that specific header. We'd like the
+ * other headers to cross-check them, but this isn't required.
+ */
+ if (sc->sm->sm_type == type)
+ return true;
+ return false;
+}
+
+/*
+ * Grab all the headers for an AG.
+ *
+ * The headers should be released by xfs_scrub_ag_free, but as a fail
+ * safe we attach all the buffers we grab to the scrub transaction so
+ * they'll all be freed when we cancel it.
+ */
+int
+xfs_scrub_ag_read_headers(
+ struct xfs_scrub_context *sc,
+ xfs_agnumber_t agno,
+ struct xfs_buf **agi,
+ struct xfs_buf **agf,
+ struct xfs_buf **agfl)
+{
+ struct xfs_mount *mp = sc->mp;
+ int error;
+
+ error = xfs_ialloc_read_agi(mp, sc->tp, agno, agi);
+ if (error && want_ag_read_header_failure(sc, XFS_SCRUB_TYPE_AGI))
+ goto out;
+
+ error = xfs_alloc_read_agf(mp, sc->tp, agno, 0, agf);
+ if (error && want_ag_read_header_failure(sc, XFS_SCRUB_TYPE_AGF))
+ goto out;
+
+ error = xfs_alloc_read_agfl(mp, sc->tp, agno, agfl);
+ if (error && want_ag_read_header_failure(sc, XFS_SCRUB_TYPE_AGFL))
+ goto out;
+
+out:
+ return error;
+}
+
+/* Release all the AG btree cursors. */
+void
+xfs_scrub_ag_btcur_free(
+ struct xfs_scrub_ag *sa)
+{
+ if (sa->refc_cur)
+ xfs_btree_del_cursor(sa->refc_cur, XFS_BTREE_ERROR);
+ if (sa->rmap_cur)
+ xfs_btree_del_cursor(sa->rmap_cur, XFS_BTREE_ERROR);
+ if (sa->fino_cur)
+ xfs_btree_del_cursor(sa->fino_cur, XFS_BTREE_ERROR);
+ if (sa->ino_cur)
+ xfs_btree_del_cursor(sa->ino_cur, XFS_BTREE_ERROR);
+ if (sa->cnt_cur)
+ xfs_btree_del_cursor(sa->cnt_cur, XFS_BTREE_ERROR);
+ if (sa->bno_cur)
+ xfs_btree_del_cursor(sa->bno_cur, XFS_BTREE_ERROR);
+
+ sa->refc_cur = NULL;
+ sa->rmap_cur = NULL;
+ sa->fino_cur = NULL;
+ sa->ino_cur = NULL;
+ sa->bno_cur = NULL;
+ sa->cnt_cur = NULL;
+}
+
+/* Initialize all the btree cursors for an AG. */
+int
+xfs_scrub_ag_btcur_init(
+ struct xfs_scrub_context *sc,
+ struct xfs_scrub_ag *sa)
+{
+ struct xfs_mount *mp = sc->mp;
+ xfs_agnumber_t agno = sa->agno;
+
+ if (sa->agf_bp) {
+ /* Set up a bnobt cursor for cross-referencing. */
+ sa->bno_cur = xfs_allocbt_init_cursor(mp, sc->tp, sa->agf_bp,
+ agno, XFS_BTNUM_BNO);
+ if (!sa->bno_cur)
+ goto err;
+
+ /* Set up a cntbt cursor for cross-referencing. */
+ sa->cnt_cur = xfs_allocbt_init_cursor(mp, sc->tp, sa->agf_bp,
+ agno, XFS_BTNUM_CNT);
+ if (!sa->cnt_cur)
+ goto err;
+ }
+
+ /* Set up a inobt cursor for cross-referencing. */
+ if (sa->agi_bp) {
+ sa->ino_cur = xfs_inobt_init_cursor(mp, sc->tp, sa->agi_bp,
+ agno, XFS_BTNUM_INO);
+ if (!sa->ino_cur)
+ goto err;
+ }
+
+ /* Set up a finobt cursor for cross-referencing. */
+ if (sa->agi_bp && xfs_sb_version_hasfinobt(&mp->m_sb)) {
+ sa->fino_cur = xfs_inobt_init_cursor(mp, sc->tp, sa->agi_bp,
+ agno, XFS_BTNUM_FINO);
+ if (!sa->fino_cur)
+ goto err;
+ }
+
+ /* Set up a rmapbt cursor for cross-referencing. */
+ if (sa->agf_bp && xfs_sb_version_hasrmapbt(&mp->m_sb)) {
+ sa->rmap_cur = xfs_rmapbt_init_cursor(mp, sc->tp, sa->agf_bp,
+ agno);
+ if (!sa->rmap_cur)
+ goto err;
+ }
+
+ /* Set up a refcountbt cursor for cross-referencing. */
+ if (sa->agf_bp && xfs_sb_version_hasreflink(&mp->m_sb)) {
+ sa->refc_cur = xfs_refcountbt_init_cursor(mp, sc->tp,
+ sa->agf_bp, agno, NULL);
+ if (!sa->refc_cur)
+ goto err;
+ }
+
+ return 0;
+err:
+ return -ENOMEM;
+}
+
+/* Release the AG header context and btree cursors. */
+void
+xfs_scrub_ag_free(
+ struct xfs_scrub_context *sc,
+ struct xfs_scrub_ag *sa)
+{
+ xfs_scrub_ag_btcur_free(sa);
+ if (sa->agfl_bp) {
+ xfs_trans_brelse(sc->tp, sa->agfl_bp);
+ sa->agfl_bp = NULL;
+ }
+ if (sa->agf_bp) {
+ xfs_trans_brelse(sc->tp, sa->agf_bp);
+ sa->agf_bp = NULL;
+ }
+ if (sa->agi_bp) {
+ xfs_trans_brelse(sc->tp, sa->agi_bp);
+ sa->agi_bp = NULL;
+ }
+ sa->agno = NULLAGNUMBER;
+}
+
+/*
+ * For scrub, grab the AGI and the AGF headers, in that order. Locking
+ * order requires us to get the AGI before the AGF. We use the
+ * transaction to avoid deadlocking on crosslinked metadata buffers;
+ * either the caller passes one in (bmap scrub) or we have to create a
+ * transaction ourselves.
+ */
+int
+xfs_scrub_ag_init(
+ struct xfs_scrub_context *sc,
+ xfs_agnumber_t agno,
+ struct xfs_scrub_ag *sa)
+{
+ int error;
+
+ sa->agno = agno;
+ error = xfs_scrub_ag_read_headers(sc, agno, &sa->agi_bp,
+ &sa->agf_bp, &sa->agfl_bp);
+ if (error)
+ return error;
+
+ return xfs_scrub_ag_btcur_init(sc, sa);
+}
+
+/* Per-scrubber setup functions */
+
+/* Set us up with a transaction and an empty context. */
+int
+xfs_scrub_setup_fs(
+ struct xfs_scrub_context *sc,
+ struct xfs_inode *ip)
+{
+ return xfs_scrub_trans_alloc(sc->sm, sc->mp, &sc->tp);
+}
+
+/* Set us up with AG headers and btree cursors. */
+int
+xfs_scrub_setup_ag_btree(
+ struct xfs_scrub_context *sc,
+ struct xfs_inode *ip,
+ bool force_log)
+{
+ struct xfs_mount *mp = sc->mp;
+ int error;
+
+ /*
+ * If the caller asks us to checkpont the log, do so. This
+ * expensive operation should be performed infrequently and only
+ * as a last resort. Any caller that sets force_log should
+ * document why they need to do so.
+ */
+ if (force_log) {
+ error = xfs_scrub_checkpoint_log(mp);
+ if (error)
+ return error;
+ }
+
+ error = xfs_scrub_setup_ag_header(sc, ip);
+ if (error)
+ return error;
+
+ return xfs_scrub_ag_init(sc, sc->sm->sm_agno, &sc->sa);
+}
+
+/* Push everything out of the log onto disk. */
+int
+xfs_scrub_checkpoint_log(
+ struct xfs_mount *mp)
+{
+ int error;
+
+ error = _xfs_log_force(mp, XFS_LOG_SYNC, NULL);
+ if (error)
+ return error;
+ xfs_ail_push_all_sync(mp->m_ail);
+ return 0;
+}
+
+/*
+ * Given an inode and the scrub control structure, grab either the
+ * inode referenced in the control structure or the inode passed in.
+ * The inode is not locked.
+ */
+int
+xfs_scrub_get_inode(
+ struct xfs_scrub_context *sc,
+ struct xfs_inode *ip_in)
+{
+ struct xfs_mount *mp = sc->mp;
+ struct xfs_inode *ip = NULL;
+ int error;
+
+ /*
+ * If userspace passed us an AG number or a generation number
+ * without an inode number, they haven't got a clue so bail out
+ * immediately.
+ */
+ if (sc->sm->sm_agno || (sc->sm->sm_gen && !sc->sm->sm_ino))
+ return -EINVAL;
+
+ /* We want to scan the inode we already had opened. */
+ if (sc->sm->sm_ino == 0 || sc->sm->sm_ino == ip_in->i_ino) {
+ sc->ip = ip_in;
+ return 0;
+ }
+
+ /* Look up the inode, see if the generation number matches. */
+ if (xfs_internal_inum(mp, sc->sm->sm_ino))
+ return -ENOENT;
+ error = xfs_iget(mp, NULL, sc->sm->sm_ino,
+ XFS_IGET_UNTRUSTED | XFS_IGET_DONTCACHE, 0, &ip);
+ if (error == -ENOENT || error == -EINVAL) {
+ /* inode doesn't exist... */
+ return -ENOENT;
+ } else if (error) {
+ trace_xfs_scrub_op_error(sc,
+ XFS_INO_TO_AGNO(mp, sc->sm->sm_ino),
+ XFS_INO_TO_AGBNO(mp, sc->sm->sm_ino),
+ error, __return_address);
+ return error;
+ }
+ if (VFS_I(ip)->i_generation != sc->sm->sm_gen) {
+ iput(VFS_I(ip));
+ return -ENOENT;
+ }
+
+ sc->ip = ip;
+ return 0;
+}
+
+/* Set us up to scrub a file's contents. */
+int
+xfs_scrub_setup_inode_contents(
+ struct xfs_scrub_context *sc,
+ struct xfs_inode *ip,
+ unsigned int resblks)
+{
+ struct xfs_mount *mp = sc->mp;
+ int error;
+
+ error = xfs_scrub_get_inode(sc, ip);
+ if (error)
+ return error;
+
+ /* Got the inode, lock it and we're ready to go. */
+ sc->ilock_flags = XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL;
+ xfs_ilock(sc->ip, sc->ilock_flags);
+ error = xfs_scrub_trans_alloc(sc->sm, mp, &sc->tp);
+ if (error)
+ goto out;
+ sc->ilock_flags |= XFS_ILOCK_EXCL;
+ xfs_ilock(sc->ip, XFS_ILOCK_EXCL);
+
+out:
+ /* scrub teardown will unlock and release the inode for us */
+ return error;
+}
generated by cgit v1.2.3 (git 2.39.0) at 2024-11-23 04:53:02 +0300