diff options
| -rw-r--r-- | fs/xfs/scrub/common.c | 201 | ||||
| -rw-r--r-- | fs/xfs/scrub/common.h | 4 | ||||
| -rw-r--r-- | fs/xfs/xfs_icache.c | 3 | ||||
| -rw-r--r-- | fs/xfs/xfs_icache.h | 1 |
4 files changed, 171 insertions, 38 deletions
diff --git a/fs/xfs/scrub/common.c b/fs/xfs/scrub/common.c index 42a25488bd25..9a811c5fa8f7 100644 --- a/fs/xfs/scrub/common.c +++ b/fs/xfs/scrub/common.c @@ -635,6 +635,14 @@ xchk_ag_init( /* Per-scrubber setup functions */ +void +xchk_trans_cancel( + struct xfs_scrub *sc) +{ + xfs_trans_cancel(sc->tp); + sc->tp = NULL; +} + /* * Grab an empty transaction so that we can re-grab locked buffers if * one of our btrees turns out to be cyclic. @@ -721,6 +729,80 @@ xchk_iget( } /* + * Try to grab an inode. If we can't, return the AGI buffer so that the caller + * can single-step the loading process to see where things went wrong. + * + * If the iget succeeds, return 0, a NULL AGI, and the inode. + * If the iget fails, return the error, the AGI, and a NULL inode. This can + * include -EINVAL and -ENOENT for invalid inode numbers or inodes that are no + * longer allocated; or any other corruption or runtime error. + * If the AGI read fails, return the error, a NULL AGI, and NULL inode. + * If a fatal signal is pending, return -EINTR, a NULL AGI, and a NULL inode. + */ +int +xchk_iget_agi( + struct xfs_scrub *sc, + xfs_ino_t inum, + struct xfs_buf **agi_bpp, + struct xfs_inode **ipp) +{ + struct xfs_mount *mp = sc->mp; + struct xfs_trans *tp = sc->tp; + struct xfs_perag *pag; + int error; + +again: + *agi_bpp = NULL; + *ipp = NULL; + error = 0; + + if (xchk_should_terminate(sc, &error)) + return error; + + pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, inum)); + error = xfs_ialloc_read_agi(pag, tp, agi_bpp); + xfs_perag_put(pag); + if (error) + return error; + + error = xfs_iget(mp, tp, inum, + XFS_IGET_NOWAIT | XFS_IGET_UNTRUSTED, 0, ipp); + if (error == -EAGAIN) { + /* + * Cached inode awaiting inactivation. Drop the AGI buffer in + * case the inactivation worker is now waiting for it, and try + * the iget again. + */ + xfs_trans_brelse(tp, *agi_bpp); + delay(1); + goto again; + } + if (error == 0) { + /* We got the inode, so we can release the AGI. */ + ASSERT(*ipp != NULL); + xfs_trans_brelse(tp, *agi_bpp); + *agi_bpp = NULL; + } + + return error; +} + +/* Install an inode that we opened by handle for scrubbing. */ +static int +xchk_install_handle_inode( + struct xfs_scrub *sc, + struct xfs_inode *ip) +{ + if (VFS_I(ip)->i_generation != sc->sm->sm_gen) { + xchk_irele(sc, ip); + return -ENOENT; + } + + sc->ip = ip; + 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. @@ -731,60 +813,105 @@ xchk_get_inode( { struct xfs_imap imap; struct xfs_mount *mp = sc->mp; + struct xfs_buf *agi_bp; struct xfs_inode *ip_in = XFS_I(file_inode(sc->file)); struct xfs_inode *ip = NULL; + xfs_agnumber_t agno = XFS_INO_TO_AGNO(mp, sc->sm->sm_ino); int error; + ASSERT(sc->tp == NULL); + /* 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. */ + /* Reject internal metadata files and obviously bad inode numbers. */ if (xfs_internal_inum(mp, sc->sm->sm_ino)) return -ENOENT; + if (!xfs_verify_ino(sc->mp, sc->sm->sm_ino)) + return -ENOENT; + + /* Try a regular untrusted iget. */ error = xchk_iget(sc, sc->sm->sm_ino, &ip); - switch (error) { - case -ENOENT: - /* Inode doesn't exist, just bail out. */ - return error; - case 0: - /* Got an inode, continue. */ - break; - case -EINVAL: - /* - * -EINVAL with IGET_UNTRUSTED could mean one of several - * things: userspace gave us an inode number that doesn't - * correspond to fs space, or doesn't have an inobt entry; - * or it could simply mean that the inode buffer failed the - * read verifiers. - * - * Try just the inode mapping lookup -- if it succeeds, then - * the inode buffer verifier failed and something needs fixing. - * Otherwise, we really couldn't find it so tell userspace - * that it no longer exists. - */ - error = xfs_imap(sc->mp, sc->tp, sc->sm->sm_ino, &imap, - XFS_IGET_UNTRUSTED); - if (error) - return -ENOENT; - error = -EFSCORRUPTED; - fallthrough; - default: - trace_xchk_op_error(sc, - XFS_INO_TO_AGNO(mp, sc->sm->sm_ino), - XFS_INO_TO_AGBNO(mp, sc->sm->sm_ino), - error, __return_address); + if (!error) + return xchk_install_handle_inode(sc, ip); + if (error == -ENOENT) return error; + if (error != -EINVAL) + goto out_error; + + /* + * EINVAL with IGET_UNTRUSTED probably means one of several things: + * userspace gave us an inode number that doesn't correspond to fs + * space; the inode btree lacks a record for this inode; or there is a + * record, and it says this inode is free. + * + * We want to look up this inode in the inobt to distinguish two + * scenarios: (1) the inobt says the inode is free, in which case + * there's nothing to do; and (2) the inobt says the inode is + * allocated, but loading it failed due to corruption. + * + * Allocate a transaction and grab the AGI to prevent inobt activity + * in this AG. Retry the iget in case someone allocated a new inode + * after the first iget failed. + */ + error = xchk_trans_alloc(sc, 0); + if (error) + goto out_error; + + error = xchk_iget_agi(sc, sc->sm->sm_ino, &agi_bp, &ip); + if (error == 0) { + /* Actually got the inode, so install it. */ + xchk_trans_cancel(sc); + return xchk_install_handle_inode(sc, ip); } - if (VFS_I(ip)->i_generation != sc->sm->sm_gen) { - xchk_irele(sc, ip); - return -ENOENT; + if (error == -ENOENT) + goto out_gone; + if (error != -EINVAL) + goto out_cancel; + + /* Ensure that we have protected against inode allocation/freeing. */ + if (agi_bp == NULL) { + ASSERT(agi_bp != NULL); + error = -ECANCELED; + goto out_cancel; } - sc->ip = ip; - return 0; + /* + * Untrusted iget failed a second time. Let's try an inobt lookup. + * If the inobt thinks this the inode neither can exist inside the + * filesystem nor is allocated, return ENOENT to signal that the check + * can be skipped. + * + * If the lookup returns corruption, we'll mark this inode corrupt and + * exit to userspace. There's little chance of fixing anything until + * the inobt is straightened out, but there's nothing we can do here. + * + * If the lookup encounters any other error, exit to userspace. + * + * If the lookup succeeds, something else must be very wrong in the fs + * such that setting up the incore inode failed in some strange way. + * Treat those as corruptions. + */ + error = xfs_imap(sc->mp, sc->tp, sc->sm->sm_ino, &imap, + XFS_IGET_UNTRUSTED); + if (error == -EINVAL || error == -ENOENT) + goto out_gone; + if (!error) + error = -EFSCORRUPTED; + +out_cancel: + xchk_trans_cancel(sc); +out_error: + trace_xchk_op_error(sc, agno, XFS_INO_TO_AGBNO(mp, sc->sm->sm_ino), + error, __return_address); + return error; +out_gone: + /* The file is gone, so there's nothing to check. */ + xchk_trans_cancel(sc); + return -ENOENT; } /* Release an inode, possibly dropping it in the process. */ diff --git a/fs/xfs/scrub/common.h b/fs/xfs/scrub/common.h index 7472c41d9cfe..6a7fe2596841 100644 --- a/fs/xfs/scrub/common.h +++ b/fs/xfs/scrub/common.h @@ -32,6 +32,8 @@ xchk_should_terminate( } int xchk_trans_alloc(struct xfs_scrub *sc, uint resblks); +void xchk_trans_cancel(struct xfs_scrub *sc); + bool xchk_process_error(struct xfs_scrub *sc, xfs_agnumber_t agno, xfs_agblock_t bno, int *error); bool xchk_fblock_process_error(struct xfs_scrub *sc, int whichfork, @@ -138,6 +140,8 @@ int xchk_setup_inode_contents(struct xfs_scrub *sc, unsigned int resblks); void xchk_buffer_recheck(struct xfs_scrub *sc, struct xfs_buf *bp); int xchk_iget(struct xfs_scrub *sc, xfs_ino_t inum, struct xfs_inode **ipp); +int xchk_iget_agi(struct xfs_scrub *sc, xfs_ino_t inum, + struct xfs_buf **agi_bpp, struct xfs_inode **ipp); void xchk_irele(struct xfs_scrub *sc, struct xfs_inode *ip); /* diff --git a/fs/xfs/xfs_icache.c b/fs/xfs/xfs_icache.c index 2bbe7916a998..dbbd5a892d25 100644 --- a/fs/xfs/xfs_icache.c +++ b/fs/xfs/xfs_icache.c @@ -761,7 +761,8 @@ again: return 0; out_error_or_again: - if (!(flags & XFS_IGET_INCORE) && error == -EAGAIN) { + if (!(flags & (XFS_IGET_INCORE | XFS_IGET_NOWAIT)) && + error == -EAGAIN) { delay(1); goto again; } diff --git a/fs/xfs/xfs_icache.h b/fs/xfs/xfs_icache.h index 6cd180721659..305a14c30b73 100644 --- a/fs/xfs/xfs_icache.h +++ b/fs/xfs/xfs_icache.h @@ -38,6 +38,7 @@ struct xfs_icwalk { #define XFS_IGET_UNTRUSTED 0x2 #define XFS_IGET_DONTCACHE 0x4 #define XFS_IGET_INCORE 0x8 /* don't read from disk or reinit */ +#define XFS_IGET_NOWAIT 0x10 /* return EAGAIN instead of blocking */ int xfs_iget(struct xfs_mount *mp, struct xfs_trans *tp, xfs_ino_t ino, uint flags, uint lock_flags, xfs_inode_t **ipp); |