diff --git a/fs/xfs/libxfs/xfs_bmap.h b/fs/xfs/libxfs/xfs_bmap.h index 9ff030d1298157..e33470e39728d5 100644 --- a/fs/xfs/libxfs/xfs_bmap.h +++ b/fs/xfs/libxfs/xfs_bmap.h @@ -145,7 +145,7 @@ static inline int xfs_bmapi_whichfork(uint32_t bmapi_flags) { BMAP_COWFORK, "COW" } /* Return true if the extent is an allocated extent, written or not. */ -static inline bool xfs_bmap_is_real_extent(struct xfs_bmbt_irec *irec) +static inline bool xfs_bmap_is_real_extent(const struct xfs_bmbt_irec *irec) { return irec->br_startblock != HOLESTARTBLOCK && irec->br_startblock != DELAYSTARTBLOCK && diff --git a/fs/xfs/scrub/bmap.c b/fs/xfs/scrub/bmap.c index e485a546a758dd..87ab9f95a487ad 100644 --- a/fs/xfs/scrub/bmap.c +++ b/fs/xfs/scrub/bmap.c @@ -96,11 +96,23 @@ xchk_setup_inode_bmap( struct xchk_bmap_info { struct xfs_scrub *sc; + + /* Incore extent tree cursor */ struct xfs_iext_cursor icur; - xfs_fileoff_t lastoff; + + /* Previous fork mapping that we examined */ + struct xfs_bmbt_irec prev_rec; + + /* Is this a realtime fork? */ bool is_rt; + + /* May mappings point to shared space? */ bool is_shared; + + /* Was the incore extent tree loaded? */ bool was_loaded; + + /* Which inode fork are we checking? */ int whichfork; }; @@ -153,49 +165,7 @@ xchk_bmap_get_rmap( return has_rmap; } -static inline bool -xchk_bmap_has_prev( - struct xchk_bmap_info *info, - struct xfs_bmbt_irec *irec) -{ - struct xfs_bmbt_irec got; - struct xfs_ifork *ifp; - - ifp = xfs_ifork_ptr(info->sc->ip, info->whichfork); - - if (!xfs_iext_peek_prev_extent(ifp, &info->icur, &got)) - return false; - if (got.br_startoff + got.br_blockcount != irec->br_startoff) - return false; - if (got.br_startblock + got.br_blockcount != irec->br_startblock) - return false; - if (got.br_state != irec->br_state) - return false; - return true; -} - -static inline bool -xchk_bmap_has_next( - struct xchk_bmap_info *info, - struct xfs_bmbt_irec *irec) -{ - struct xfs_bmbt_irec got; - struct xfs_ifork *ifp; - - ifp = xfs_ifork_ptr(info->sc->ip, info->whichfork); - - if (!xfs_iext_peek_next_extent(ifp, &info->icur, &got)) - return false; - if (irec->br_startoff + irec->br_blockcount != got.br_startoff) - return false; - if (irec->br_startblock + irec->br_blockcount != got.br_startblock) - return false; - if (got.br_state != irec->br_state) - return false; - return true; -} - -/* Make sure that we have rmapbt records for this extent. */ +/* Make sure that we have rmapbt records for this data/attr fork extent. */ STATIC void xchk_bmap_xref_rmap( struct xchk_bmap_info *info, @@ -204,41 +174,39 @@ xchk_bmap_xref_rmap( { struct xfs_rmap_irec rmap; unsigned long long rmap_end; - uint64_t owner; + uint64_t owner = info->sc->ip->i_ino; if (!info->sc->sa.rmap_cur || xchk_skip_xref(info->sc->sm)) return; - if (info->whichfork == XFS_COW_FORK) - owner = XFS_RMAP_OWN_COW; - else - owner = info->sc->ip->i_ino; - /* Find the rmap record for this irec. */ if (!xchk_bmap_get_rmap(info, irec, agbno, owner, &rmap)) return; - /* Check the rmap. */ + /* + * The rmap must be an exact match for this incore file mapping record, + * which may have arisen from multiple ondisk records. + */ + if (rmap.rm_startblock != agbno) + xchk_fblock_xref_set_corrupt(info->sc, info->whichfork, + irec->br_startoff); + rmap_end = (unsigned long long)rmap.rm_startblock + rmap.rm_blockcount; - if (rmap.rm_startblock > agbno || - agbno + irec->br_blockcount > rmap_end) + if (rmap_end != agbno + irec->br_blockcount) xchk_fblock_xref_set_corrupt(info->sc, info->whichfork, irec->br_startoff); - /* - * Check the logical offsets if applicable. CoW staging extents - * don't track logical offsets since the mappings only exist in - * memory. - */ - if (info->whichfork != XFS_COW_FORK) { - rmap_end = (unsigned long long)rmap.rm_offset + - rmap.rm_blockcount; - if (rmap.rm_offset > irec->br_startoff || - irec->br_startoff + irec->br_blockcount > rmap_end) - xchk_fblock_xref_set_corrupt(info->sc, - info->whichfork, irec->br_startoff); - } + /* Check the logical offsets. */ + if (rmap.rm_offset != irec->br_startoff) + xchk_fblock_xref_set_corrupt(info->sc, info->whichfork, + irec->br_startoff); + + rmap_end = (unsigned long long)rmap.rm_offset + rmap.rm_blockcount; + if (rmap_end != irec->br_startoff + irec->br_blockcount) + xchk_fblock_xref_set_corrupt(info->sc, info->whichfork, + irec->br_startoff); + /* Check the owner */ if (rmap.rm_owner != owner) xchk_fblock_xref_set_corrupt(info->sc, info->whichfork, irec->br_startoff); @@ -250,8 +218,7 @@ xchk_bmap_xref_rmap( * records because the blocks are owned (on-disk) by the refcountbt, * which doesn't track unwritten state. */ - if (owner != XFS_RMAP_OWN_COW && - !!(irec->br_state == XFS_EXT_UNWRITTEN) != + if (!!(irec->br_state == XFS_EXT_UNWRITTEN) != !!(rmap.rm_flags & XFS_RMAP_UNWRITTEN)) xchk_fblock_xref_set_corrupt(info->sc, info->whichfork, irec->br_startoff); @@ -263,34 +230,60 @@ xchk_bmap_xref_rmap( if (rmap.rm_flags & XFS_RMAP_BMBT_BLOCK) xchk_fblock_xref_set_corrupt(info->sc, info->whichfork, irec->br_startoff); +} + +/* Make sure that we have rmapbt records for this COW fork extent. */ +STATIC void +xchk_bmap_xref_rmap_cow( + struct xchk_bmap_info *info, + struct xfs_bmbt_irec *irec, + xfs_agblock_t agbno) +{ + struct xfs_rmap_irec rmap; + unsigned long long rmap_end; + uint64_t owner = XFS_RMAP_OWN_COW; + + if (!info->sc->sa.rmap_cur || xchk_skip_xref(info->sc->sm)) + return; + + /* Find the rmap record for this irec. */ + if (!xchk_bmap_get_rmap(info, irec, agbno, owner, &rmap)) + return; /* - * If the rmap starts before this bmbt record, make sure there's a bmbt - * record for the previous offset that is contiguous with this mapping. - * Skip this for CoW fork extents because the refcount btree (and not - * the inode) is the ondisk owner for those extents. + * CoW staging extents are owned by the refcount btree, so the rmap + * can start before and end after the physical space allocated to this + * mapping. There are no offsets to check. */ - if (info->whichfork != XFS_COW_FORK && rmap.rm_startblock < agbno && - !xchk_bmap_has_prev(info, irec)) { + if (rmap.rm_startblock > agbno) + xchk_fblock_xref_set_corrupt(info->sc, info->whichfork, + irec->br_startoff); + + rmap_end = (unsigned long long)rmap.rm_startblock + rmap.rm_blockcount; + if (rmap_end < agbno + irec->br_blockcount) + xchk_fblock_xref_set_corrupt(info->sc, info->whichfork, + irec->br_startoff); + + /* Check the owner */ + if (rmap.rm_owner != owner) xchk_fblock_xref_set_corrupt(info->sc, info->whichfork, irec->br_startoff); - return; - } /* - * If the rmap ends after this bmbt record, make sure there's a bmbt - * record for the next offset that is contiguous with this mapping. - * Skip this for CoW fork extents because the refcount btree (and not - * the inode) is the ondisk owner for those extents. + * No flags allowed. Note that the (in-memory) CoW fork distinguishes + * between unwritten and written extents, but we don't track that in + * the rmap records because the blocks are owned (on-disk) by the + * refcountbt, which doesn't track unwritten state. */ - rmap_end = (unsigned long long)rmap.rm_startblock + rmap.rm_blockcount; - if (info->whichfork != XFS_COW_FORK && - rmap_end > agbno + irec->br_blockcount && - !xchk_bmap_has_next(info, irec)) { + if (rmap.rm_flags & XFS_RMAP_ATTR_FORK) + xchk_fblock_xref_set_corrupt(info->sc, info->whichfork, + irec->br_startoff); + if (rmap.rm_flags & XFS_RMAP_BMBT_BLOCK) + xchk_fblock_xref_set_corrupt(info->sc, info->whichfork, + irec->br_startoff); + if (rmap.rm_flags & XFS_RMAP_UNWRITTEN) xchk_fblock_xref_set_corrupt(info->sc, info->whichfork, irec->br_startoff); - return; - } } /* Cross-reference a single rtdev extent record. */ @@ -329,9 +322,9 @@ xchk_bmap_iextent_xref( xchk_xref_is_used_space(info->sc, agbno, len); xchk_xref_is_not_inode_chunk(info->sc, agbno, len); - xchk_bmap_xref_rmap(info, irec, agbno); switch (info->whichfork) { case XFS_DATA_FORK: + xchk_bmap_xref_rmap(info, irec, agbno); if (!xfs_is_reflink_inode(info->sc->ip)) { xfs_rmap_ino_owner(&oinfo, info->sc->ip->i_ino, info->whichfork, irec->br_startoff); @@ -344,6 +337,7 @@ xchk_bmap_iextent_xref( irec->br_blockcount); break; case XFS_ATTR_FORK: + xchk_bmap_xref_rmap(info, irec, agbno); xfs_rmap_ino_owner(&oinfo, info->sc->ip->i_ino, info->whichfork, irec->br_startoff); xchk_xref_is_only_owned_by(info->sc, agbno, irec->br_blockcount, @@ -354,6 +348,7 @@ xchk_bmap_iextent_xref( irec->br_blockcount); break; case XFS_COW_FORK: + xchk_bmap_xref_rmap_cow(info, irec, agbno); xchk_xref_is_only_owned_by(info->sc, agbno, irec->br_blockcount, &XFS_RMAP_OINFO_COW); xchk_xref_is_cow_staging(info->sc, agbno, @@ -405,7 +400,8 @@ xchk_bmap_iextent( * Check for out-of-order extents. This record could have come * from the incore list, for which there is no ordering check. */ - if (irec->br_startoff < info->lastoff) + if (irec->br_startoff < info->prev_rec.br_startoff + + info->prev_rec.br_blockcount) xchk_fblock_set_corrupt(info->sc, info->whichfork, irec->br_startoff); @@ -415,15 +411,7 @@ xchk_bmap_iextent( xchk_bmap_dirattr_extent(ip, info, irec); - /* There should never be a "hole" extent in either extent list. */ - if (irec->br_startblock == HOLESTARTBLOCK) - xchk_fblock_set_corrupt(info->sc, info->whichfork, - irec->br_startoff); - /* Make sure the extent points to a valid place. */ - if (irec->br_blockcount > XFS_MAX_BMBT_EXTLEN) - xchk_fblock_set_corrupt(info->sc, info->whichfork, - irec->br_startoff); if (info->is_rt && !xfs_verify_rtext(mp, irec->br_startblock, irec->br_blockcount)) xchk_fblock_set_corrupt(info->sc, info->whichfork, @@ -647,45 +635,57 @@ xchk_bmap_check_ag_rmaps( return error; } -/* Make sure each rmap has a corresponding bmbt entry. */ -STATIC int -xchk_bmap_check_rmaps( - struct xfs_scrub *sc, - int whichfork) +/* + * Decide if we want to walk every rmap btree in the fs to make sure that each + * rmap for this file fork has corresponding bmbt entries. + */ +static bool +xchk_bmap_want_check_rmaps( + struct xchk_bmap_info *info) { - struct xfs_ifork *ifp = xfs_ifork_ptr(sc->ip, whichfork); - struct xfs_perag *pag; - xfs_agnumber_t agno; - bool zero_size; - int error; + struct xfs_scrub *sc = info->sc; + struct xfs_ifork *ifp; - if (!xfs_has_rmapbt(sc->mp) || - whichfork == XFS_COW_FORK || - (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)) - return 0; + if (!xfs_has_rmapbt(sc->mp)) + return false; + if (info->whichfork == XFS_COW_FORK) + return false; + if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT) + return false; /* Don't support realtime rmap checks yet. */ - if (XFS_IS_REALTIME_INODE(sc->ip) && whichfork == XFS_DATA_FORK) - return 0; - - ASSERT(xfs_ifork_ptr(sc->ip, whichfork) != NULL); + if (info->is_rt) + return false; /* - * Only do this for complex maps that are in btree format, or for - * situations where we would seem to have a size but zero extents. - * The inode repair code can zap broken iforks, which means we have - * to flag this bmap as corrupt if there are rmaps that need to be - * reattached. + * The inode repair code zaps broken inode forks by resetting them back + * to EXTENTS format and zero extent records. If we encounter a fork + * in this state along with evidence that the fork isn't supposed to be + * empty, we need to scan the reverse mappings to decide if we're going + * to rebuild the fork. Data forks with nonzero file size are scanned. + * xattr forks are never empty of content, so they are always scanned. */ + ifp = xfs_ifork_ptr(sc->ip, info->whichfork); + if (ifp->if_format == XFS_DINODE_FMT_EXTENTS && ifp->if_nextents == 0) { + if (info->whichfork == XFS_DATA_FORK && + i_size_read(VFS_I(sc->ip)) == 0) + return false; - if (whichfork == XFS_DATA_FORK) - zero_size = i_size_read(VFS_I(sc->ip)) == 0; - else - zero_size = false; + return true; + } - if (ifp->if_format != XFS_DINODE_FMT_BTREE && - (zero_size || ifp->if_nextents > 0)) - return 0; + return false; +} + +/* Make sure each rmap has a corresponding bmbt entry. */ +STATIC int +xchk_bmap_check_rmaps( + struct xfs_scrub *sc, + int whichfork) +{ + struct xfs_perag *pag; + xfs_agnumber_t agno; + int error; for_each_perag(sc->mp, agno, pag) { error = xchk_bmap_check_ag_rmaps(sc, whichfork, pag); @@ -712,7 +712,8 @@ xchk_bmap_iextent_delalloc( * Check for out-of-order extents. This record could have come * from the incore list, for which there is no ordering check. */ - if (irec->br_startoff < info->lastoff) + if (irec->br_startoff < info->prev_rec.br_startoff + + info->prev_rec.br_blockcount) xchk_fblock_set_corrupt(info->sc, info->whichfork, irec->br_startoff); @@ -726,6 +727,101 @@ xchk_bmap_iextent_delalloc( irec->br_startoff); } +/* Decide if this individual fork mapping is ok. */ +static bool +xchk_bmap_iext_mapping( + struct xchk_bmap_info *info, + const struct xfs_bmbt_irec *irec) +{ + /* There should never be a "hole" extent in either extent list. */ + if (irec->br_startblock == HOLESTARTBLOCK) + return false; + if (irec->br_blockcount > XFS_MAX_BMBT_EXTLEN) + return false; + return true; +} + +/* Are these two mappings contiguous with each other? */ +static inline bool +xchk_are_bmaps_contiguous( + const struct xfs_bmbt_irec *b1, + const struct xfs_bmbt_irec *b2) +{ + /* Don't try to combine unallocated mappings. */ + if (!xfs_bmap_is_real_extent(b1)) + return false; + if (!xfs_bmap_is_real_extent(b2)) + return false; + + /* Does b2 come right after b1 in the logical and physical range? */ + if (b1->br_startoff + b1->br_blockcount != b2->br_startoff) + return false; + if (b1->br_startblock + b1->br_blockcount != b2->br_startblock) + return false; + if (b1->br_state != b2->br_state) + return false; + return true; +} + +/* + * Walk the incore extent records, accumulating consecutive contiguous records + * into a single incore mapping. Returns true if @irec has been set to a + * mapping or false if there are no more mappings. Caller must ensure that + * @info.icur is zeroed before the first call. + */ +static int +xchk_bmap_iext_iter( + struct xchk_bmap_info *info, + struct xfs_bmbt_irec *irec) +{ + struct xfs_bmbt_irec got; + struct xfs_ifork *ifp; + xfs_filblks_t prev_len; + + ifp = xfs_ifork_ptr(info->sc->ip, info->whichfork); + + /* Advance to the next iextent record and check the mapping. */ + xfs_iext_next(ifp, &info->icur); + if (!xfs_iext_get_extent(ifp, &info->icur, irec)) + return false; + + if (!xchk_bmap_iext_mapping(info, irec)) { + xchk_fblock_set_corrupt(info->sc, info->whichfork, + irec->br_startoff); + return false; + } + + /* + * Iterate subsequent iextent records and merge them with the one + * that we just read, if possible. + */ + prev_len = irec->br_blockcount; + while (xfs_iext_peek_next_extent(ifp, &info->icur, &got)) { + if (!xchk_are_bmaps_contiguous(irec, &got)) + break; + + if (!xchk_bmap_iext_mapping(info, &got)) { + xchk_fblock_set_corrupt(info->sc, info->whichfork, + got.br_startoff); + return false; + } + + /* + * Notify the user of mergeable records in the data or attr + * forks. CoW forks only exist in memory so we ignore them. + */ + if (info->whichfork != XFS_COW_FORK && + prev_len + got.br_blockcount > BMBT_BLOCKCOUNT_MASK) + xchk_ino_set_preen(info->sc, info->sc->ip->i_ino); + + irec->br_blockcount += got.br_blockcount; + prev_len = got.br_blockcount; + xfs_iext_next(ifp, &info->icur); + } + + return true; +} + /* * Scrub an inode fork's block mappings. * @@ -805,10 +901,15 @@ xchk_bmap( if (!xchk_fblock_process_error(sc, whichfork, 0, &error)) goto out; - /* Scrub extent records. */ - info.lastoff = 0; - ifp = xfs_ifork_ptr(ip, whichfork); - for_each_xfs_iext(ifp, &info.icur, &irec) { + /* + * Scrub extent records. We use a special iterator function here that + * combines adjacent mappings if they are logically and physically + * contiguous. For large allocations that require multiple bmbt + * records, this reduces the number of cross-referencing calls, which + * reduces runtime. Cross referencing with the rmap is simpler because + * the rmap must match the combined mapping exactly. + */ + while (xchk_bmap_iext_iter(&info, &irec)) { if (xchk_should_terminate(sc, &error) || (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)) goto out; @@ -823,12 +924,14 @@ xchk_bmap( xchk_bmap_iextent_delalloc(ip, &info, &irec); else xchk_bmap_iextent(ip, &info, &irec); - info.lastoff = irec.br_startoff + irec.br_blockcount; + memcpy(&info.prev_rec, &irec, sizeof(struct xfs_bmbt_irec)); } - error = xchk_bmap_check_rmaps(sc, whichfork); - if (!xchk_fblock_xref_process_error(sc, whichfork, 0, &error)) - goto out; + if (xchk_bmap_want_check_rmaps(&info)) { + error = xchk_bmap_check_rmaps(sc, whichfork); + if (!xchk_fblock_xref_process_error(sc, whichfork, 0, &error)) + goto out; + } out: return error; }