diff options
Diffstat (limited to 'fs/xfs/scrub/common.c')
| -rw-r--r-- | fs/xfs/scrub/common.c | 574 |
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; +} |