diff options
Diffstat (limited to 'fs/xfs/scrub/inode.c')
-rw-r--r-- | fs/xfs/scrub/inode.c | 177 |
1 files changed, 154 insertions, 23 deletions
diff --git a/fs/xfs/scrub/inode.c b/fs/xfs/scrub/inode.c index 2db96c8a71dc..3e1e02e340a6 100644 --- a/fs/xfs/scrub/inode.c +++ b/fs/xfs/scrub/inode.c @@ -11,8 +11,11 @@ #include "xfs_mount.h" #include "xfs_btree.h" #include "xfs_log_format.h" +#include "xfs_trans.h" +#include "xfs_ag.h" #include "xfs_inode.h" #include "xfs_ialloc.h" +#include "xfs_icache.h" #include "xfs_da_format.h" #include "xfs_reflink.h" #include "xfs_rmap.h" @@ -20,48 +23,176 @@ #include "scrub/scrub.h" #include "scrub/common.h" #include "scrub/btree.h" +#include "scrub/trace.h" + +/* Prepare the attached inode for scrubbing. */ +static inline int +xchk_prepare_iscrub( + struct xfs_scrub *sc) +{ + int error; + + sc->ilock_flags = XFS_IOLOCK_EXCL; + xfs_ilock(sc->ip, sc->ilock_flags); + + error = xchk_trans_alloc(sc, 0); + if (error) + return error; + + sc->ilock_flags |= XFS_ILOCK_EXCL; + xfs_ilock(sc->ip, XFS_ILOCK_EXCL); + return 0; +} + +/* Install this scrub-by-handle inode and prepare it for scrubbing. */ +static inline int +xchk_install_handle_iscrub( + struct xfs_scrub *sc, + struct xfs_inode *ip) +{ + int error; + + error = xchk_install_handle_inode(sc, ip); + if (error) + return error; + + return xchk_prepare_iscrub(sc); +} /* - * Grab total control of the inode metadata. It doesn't matter here if - * the file data is still changing; exclusive access to the metadata is - * the goal. + * Grab total control of the inode metadata. In the best case, we grab the + * incore inode and take all locks on it. If the incore inode cannot be + * constructed due to corruption problems, lock the AGI so that we can single + * step the loading process to fix everything that can go wrong. */ int xchk_setup_inode( struct xfs_scrub *sc) { + struct xfs_imap imap; + struct xfs_inode *ip; + struct xfs_mount *mp = sc->mp; + struct xfs_inode *ip_in = XFS_I(file_inode(sc->file)); + struct xfs_buf *agi_bp; + struct xfs_perag *pag; + xfs_agnumber_t agno = XFS_INO_TO_AGNO(mp, sc->sm->sm_ino); int error; if (xchk_need_intent_drain(sc)) xchk_fsgates_enable(sc, XCHK_FSGATES_DRAIN); + /* We want to scan the opened inode, so lock it and exit. */ + if (sc->sm->sm_ino == 0 || sc->sm->sm_ino == ip_in->i_ino) { + sc->ip = ip_in; + return xchk_prepare_iscrub(sc); + } + + /* 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); + if (!error) + return xchk_install_handle_iscrub(sc, ip); + if (error == -ENOENT) + return error; + if (error != -EFSCORRUPTED && error != -EFSBADCRC && error != -EINVAL) + goto out_error; + /* - * Try to get the inode. If the verifiers fail, we try again - * in raw mode. + * 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. + * + * EFSCORRUPTED/EFSBADCRC could mean that the inode was mappable, but + * some other metadata corruption (e.g. inode forks) prevented + * instantiation of the incore inode. Or it could mean the inobt is + * corrupt. + * + * We want to look up this inode in the inobt directly to distinguish + * three different scenarios: (1) the inobt says the inode is free, + * in which case there's nothing to do; (2) the inobt is corrupt so we + * should flag the corruption and exit to userspace to let it fix the + * inobt; and (3) 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_get_inode(sc); - switch (error) { - case 0: - break; - case -EFSCORRUPTED: - case -EFSBADCRC: - return xchk_trans_alloc(sc, 0); - default: - return error; + 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 incore inode, so install it and proceed. */ + xchk_trans_cancel(sc); + return xchk_install_handle_iscrub(sc, ip); + } + if (error == -ENOENT) + goto out_gone; + if (error != -EFSCORRUPTED && error != -EFSBADCRC && 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; } - /* 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 = xchk_trans_alloc(sc, 0); + /* + * Untrusted iget failed a second time. Let's try an inobt lookup. + * If the inobt doesn't think this is an allocated inode then we'll + * return ENOENT to signal that the check can be skipped. + * + * If the lookup signals 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 a runtime error, exit to userspace. + */ + pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, sc->sm->sm_ino)); + if (!pag) { + error = -EFSCORRUPTED; + goto out_cancel; + } + + error = xfs_imap(pag, sc->tp, sc->sm->sm_ino, &imap, + XFS_IGET_UNTRUSTED); + xfs_perag_put(pag); + if (error == -EINVAL || error == -ENOENT) + goto out_gone; if (error) - goto out; - sc->ilock_flags |= XFS_ILOCK_EXCL; - xfs_ilock(sc->ip, XFS_ILOCK_EXCL); + goto out_cancel; -out: - /* scrub teardown will unlock and release the inode for us */ + /* + * The lookup succeeded. Chances are the ondisk inode is corrupt and + * preventing iget from reading it. Retain the scrub transaction and + * the AGI buffer to prevent anyone from allocating or freeing inodes. + * This ensures that we preserve the inconsistency between the inobt + * saying the inode is allocated and the icache being unable to load + * the inode until we can flag the corruption in xchk_inode. The + * scrub function has to note the corruption, since we're not really + * supposed to do that from the setup function. + */ + return 0; + +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; } /* Inode core */ |