From d0b2f91bede3bd5e3d24dd6803e56eee959c1797 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Thu, 20 Oct 2016 00:10:27 -0300 Subject: Linux-libre 4.8.2-gnu --- fs/xfs/libxfs/xfs_alloc.c | 262 ++++++++++++++++++++++++++++++++++++---------- 1 file changed, 207 insertions(+), 55 deletions(-) (limited to 'fs/xfs/libxfs/xfs_alloc.c') diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c index a708e38b4..05b5243d8 100644 --- a/fs/xfs/libxfs/xfs_alloc.c +++ b/fs/xfs/libxfs/xfs_alloc.c @@ -24,8 +24,10 @@ #include "xfs_bit.h" #include "xfs_sb.h" #include "xfs_mount.h" +#include "xfs_defer.h" #include "xfs_inode.h" #include "xfs_btree.h" +#include "xfs_rmap.h" #include "xfs_alloc_btree.h" #include "xfs_alloc.h" #include "xfs_extent_busy.h" @@ -49,6 +51,81 @@ STATIC int xfs_alloc_ag_vextent_size(xfs_alloc_arg_t *); STATIC int xfs_alloc_ag_vextent_small(xfs_alloc_arg_t *, xfs_btree_cur_t *, xfs_agblock_t *, xfs_extlen_t *, int *); +xfs_extlen_t +xfs_prealloc_blocks( + struct xfs_mount *mp) +{ + if (xfs_sb_version_hasrmapbt(&mp->m_sb)) + return XFS_RMAP_BLOCK(mp) + 1; + if (xfs_sb_version_hasfinobt(&mp->m_sb)) + return XFS_FIBT_BLOCK(mp) + 1; + return XFS_IBT_BLOCK(mp) + 1; +} + +/* + * In order to avoid ENOSPC-related deadlock caused by out-of-order locking of + * AGF buffer (PV 947395), we place constraints on the relationship among + * actual allocations for data blocks, freelist blocks, and potential file data + * bmap btree blocks. However, these restrictions may result in no actual space + * allocated for a delayed extent, for example, a data block in a certain AG is + * allocated but there is no additional block for the additional bmap btree + * block due to a split of the bmap btree of the file. The result of this may + * lead to an infinite loop when the file gets flushed to disk and all delayed + * extents need to be actually allocated. To get around this, we explicitly set + * aside a few blocks which will not be reserved in delayed allocation. + * + * When rmap is disabled, we need to reserve 4 fsbs _per AG_ for the freelist + * and 4 more to handle a potential split of the file's bmap btree. + * + * When rmap is enabled, we must also be able to handle two rmap btree inserts + * to record both the file data extent and a new bmbt block. The bmbt block + * might not be in the same AG as the file data extent. In the worst case + * the bmap btree splits multiple levels and all the new blocks come from + * different AGs, so set aside enough to handle rmap btree splits in all AGs. + */ +unsigned int +xfs_alloc_set_aside( + struct xfs_mount *mp) +{ + unsigned int blocks; + + blocks = 4 + (mp->m_sb.sb_agcount * XFS_ALLOC_AGFL_RESERVE); + if (xfs_sb_version_hasrmapbt(&mp->m_sb)) + blocks += mp->m_sb.sb_agcount * mp->m_rmap_maxlevels; + return blocks; +} + +/* + * When deciding how much space to allocate out of an AG, we limit the + * allocation maximum size to the size the AG. However, we cannot use all the + * blocks in the AG - some are permanently used by metadata. These + * blocks are generally: + * - the AG superblock, AGF, AGI and AGFL + * - the AGF (bno and cnt) and AGI btree root blocks, and optionally + * the AGI free inode and rmap btree root blocks. + * - blocks on the AGFL according to xfs_alloc_set_aside() limits + * - the rmapbt root block + * + * The AG headers are sector sized, so the amount of space they take up is + * dependent on filesystem geometry. The others are all single blocks. + */ +unsigned int +xfs_alloc_ag_max_usable( + struct xfs_mount *mp) +{ + unsigned int blocks; + + blocks = XFS_BB_TO_FSB(mp, XFS_FSS_TO_BB(mp, 4)); /* ag headers */ + blocks += XFS_ALLOC_AGFL_RESERVE; + blocks += 3; /* AGF, AGI btree root blocks */ + if (xfs_sb_version_hasfinobt(&mp->m_sb)) + blocks++; /* finobt root block */ + if (xfs_sb_version_hasrmapbt(&mp->m_sb)) + blocks++; /* rmap root block */ + + return mp->m_sb.sb_agblocks - blocks; +} + /* * Lookup the record equal to [bno, len] in the btree given by cur. */ @@ -84,7 +161,7 @@ xfs_alloc_lookup_ge( * Lookup the first record less than or equal to [bno, len] * in the btree given by cur. */ -int /* error */ +static int /* error */ xfs_alloc_lookup_le( struct xfs_btree_cur *cur, /* btree cursor */ xfs_agblock_t bno, /* starting block of extent */ @@ -636,6 +713,14 @@ xfs_alloc_ag_vextent( ASSERT(!args->wasfromfl || !args->isfl); ASSERT(args->agbno % args->alignment == 0); + /* if not file data, insert new block into the reverse map btree */ + if (args->oinfo.oi_owner != XFS_RMAP_OWN_UNKNOWN) { + error = xfs_rmap_alloc(args->tp, args->agbp, args->agno, + args->agbno, args->len, &args->oinfo); + if (error) + return error; + } + if (!args->wasfromfl) { error = xfs_alloc_update_counters(args->tp, args->pag, args->agbp, @@ -1497,6 +1582,7 @@ xfs_alloc_ag_vextent_small( xfs_extlen_t *flenp, /* result length */ int *stat) /* status: 0-freelist, 1-normal/none */ { + struct xfs_owner_info oinfo; int error; xfs_agblock_t fbno; xfs_extlen_t flen; @@ -1539,6 +1625,18 @@ xfs_alloc_ag_vextent_small( error0); args->wasfromfl = 1; trace_xfs_alloc_small_freelist(args); + + /* + * If we're feeding an AGFL block to something that + * doesn't live in the free space, we need to clear + * out the OWN_AG rmap. + */ + xfs_rmap_ag_owner(&oinfo, XFS_RMAP_OWN_AG); + error = xfs_rmap_free(args->tp, args->agbp, args->agno, + fbno, 1, &oinfo); + if (error) + goto error0; + *stat = 0; return 0; } @@ -1577,14 +1675,15 @@ error0: /* * Free the extent starting at agno/bno for length. */ -STATIC int /* error */ +STATIC int xfs_free_ag_extent( - xfs_trans_t *tp, /* transaction pointer */ - xfs_buf_t *agbp, /* buffer for a.g. freelist header */ - xfs_agnumber_t agno, /* allocation group number */ - xfs_agblock_t bno, /* starting block number */ - xfs_extlen_t len, /* length of extent */ - int isfl) /* set if is freelist blocks - no sb acctg */ + xfs_trans_t *tp, + xfs_buf_t *agbp, + xfs_agnumber_t agno, + xfs_agblock_t bno, + xfs_extlen_t len, + struct xfs_owner_info *oinfo, + int isfl) { xfs_btree_cur_t *bno_cur; /* cursor for by-block btree */ xfs_btree_cur_t *cnt_cur; /* cursor for by-size btree */ @@ -1601,12 +1700,19 @@ xfs_free_ag_extent( xfs_extlen_t nlen; /* new length of freespace */ xfs_perag_t *pag; /* per allocation group data */ + bno_cur = cnt_cur = NULL; mp = tp->t_mountp; + + if (oinfo->oi_owner != XFS_RMAP_OWN_UNKNOWN) { + error = xfs_rmap_free(tp, agbp, agno, bno, len, oinfo); + if (error) + goto error0; + } + /* * Allocate and initialize a cursor for the by-block btree. */ bno_cur = xfs_allocbt_init_cursor(mp, tp, agbp, agno, XFS_BTNUM_BNO); - cnt_cur = NULL; /* * Look for a neighboring block on the left (lower block numbers) * that is contiguous with this space. @@ -1839,19 +1945,8 @@ void xfs_alloc_compute_maxlevels( xfs_mount_t *mp) /* file system mount structure */ { - int level; - uint maxblocks; - uint maxleafents; - int minleafrecs; - int minnoderecs; - - maxleafents = (mp->m_sb.sb_agblocks + 1) / 2; - minleafrecs = mp->m_alloc_mnr[0]; - minnoderecs = mp->m_alloc_mnr[1]; - maxblocks = (maxleafents + minleafrecs - 1) / minleafrecs; - for (level = 1; maxblocks > 1; level++) - maxblocks = (maxblocks + minnoderecs - 1) / minnoderecs; - mp->m_ag_maxlevels = level; + mp->m_ag_maxlevels = xfs_btree_compute_maxlevels(mp, mp->m_alloc_mnr, + (mp->m_sb.sb_agblocks + 1) / 2); } /* @@ -1886,6 +1981,11 @@ xfs_alloc_min_freelist( /* space needed by-size freespace btree */ min_free += min_t(unsigned int, pag->pagf_levels[XFS_BTNUM_CNTi] + 1, mp->m_ag_maxlevels); + /* space needed reverse mapping used space btree */ + if (xfs_sb_version_hasrmapbt(&mp->m_sb)) + min_free += min_t(unsigned int, + pag->pagf_levels[XFS_BTNUM_RMAPi] + 1, + mp->m_rmap_maxlevels); return min_free; } @@ -2003,21 +2103,34 @@ xfs_alloc_fix_freelist( * anything other than extra overhead when we need to put more blocks * back on the free list? Maybe we should only do this when space is * getting low or the AGFL is more than half full? + * + * The NOSHRINK flag prevents the AGFL from being shrunk if it's too + * big; the NORMAP flag prevents AGFL expand/shrink operations from + * updating the rmapbt. Both flags are used in xfs_repair while we're + * rebuilding the rmapbt, and neither are used by the kernel. They're + * both required to ensure that rmaps are correctly recorded for the + * regenerated AGFL, bnobt, and cntbt. See repair/phase5.c and + * repair/rmap.c in xfsprogs for details. */ - while (pag->pagf_flcount > need) { + memset(&targs, 0, sizeof(targs)); + if (flags & XFS_ALLOC_FLAG_NORMAP) + xfs_rmap_skip_owner_update(&targs.oinfo); + else + xfs_rmap_ag_owner(&targs.oinfo, XFS_RMAP_OWN_AG); + while (!(flags & XFS_ALLOC_FLAG_NOSHRINK) && pag->pagf_flcount > need) { struct xfs_buf *bp; error = xfs_alloc_get_freelist(tp, agbp, &bno, 0); if (error) goto out_agbp_relse; - error = xfs_free_ag_extent(tp, agbp, args->agno, bno, 1, 1); + error = xfs_free_ag_extent(tp, agbp, args->agno, bno, 1, + &targs.oinfo, 1); if (error) goto out_agbp_relse; bp = xfs_btree_get_bufs(mp, tp, args->agno, bno, 0); xfs_trans_binval(tp, bp); } - memset(&targs, 0, sizeof(targs)); targs.tp = tp; targs.mp = mp; targs.agbp = agbp; @@ -2164,6 +2277,9 @@ xfs_alloc_log_agf( offsetof(xfs_agf_t, agf_longest), offsetof(xfs_agf_t, agf_btreeblks), offsetof(xfs_agf_t, agf_uuid), + offsetof(xfs_agf_t, agf_rmap_blocks), + /* needed so that we don't log the whole rest of the structure: */ + offsetof(xfs_agf_t, agf_spare64), sizeof(xfs_agf_t) }; @@ -2282,6 +2398,10 @@ xfs_agf_verify( be32_to_cpu(agf->agf_levels[XFS_BTNUM_CNT]) > XFS_BTREE_MAXLEVELS) return false; + if (xfs_sb_version_hasrmapbt(&mp->m_sb) && + be32_to_cpu(agf->agf_levels[XFS_BTNUM_RMAP]) > XFS_BTREE_MAXLEVELS) + return false; + /* * during growfs operations, the perag is not fully initialised, * so we can't use it for any useful checking. growfs ensures we can't @@ -2413,6 +2533,8 @@ xfs_alloc_read_agf( be32_to_cpu(agf->agf_levels[XFS_BTNUM_BNOi]); pag->pagf_levels[XFS_BTNUM_CNTi] = be32_to_cpu(agf->agf_levels[XFS_BTNUM_CNTi]); + pag->pagf_levels[XFS_BTNUM_RMAPi] = + be32_to_cpu(agf->agf_levels[XFS_BTNUM_RMAPi]); spin_lock_init(&pag->pagb_lock); pag->pagb_count = 0; pag->pagb_tree = RB_ROOT; @@ -2658,55 +2780,85 @@ error0: return error; } -/* - * Free an extent. - * Just break up the extent address and hand off to xfs_free_ag_extent - * after fixing up the freelist. - */ -int /* error */ -xfs_free_extent( - xfs_trans_t *tp, /* transaction pointer */ - xfs_fsblock_t bno, /* starting block number of extent */ - xfs_extlen_t len) /* length of extent */ +/* Ensure that the freelist is at full capacity. */ +int +xfs_free_extent_fix_freelist( + struct xfs_trans *tp, + xfs_agnumber_t agno, + struct xfs_buf **agbp) { - xfs_alloc_arg_t args; - int error; + struct xfs_alloc_arg args; + int error; - ASSERT(len != 0); - memset(&args, 0, sizeof(xfs_alloc_arg_t)); + memset(&args, 0, sizeof(struct xfs_alloc_arg)); args.tp = tp; args.mp = tp->t_mountp; + args.agno = agno; /* * validate that the block number is legal - the enables us to detect * and handle a silent filesystem corruption rather than crashing. */ - args.agno = XFS_FSB_TO_AGNO(args.mp, bno); if (args.agno >= args.mp->m_sb.sb_agcount) return -EFSCORRUPTED; - args.agbno = XFS_FSB_TO_AGBNO(args.mp, bno); - if (args.agbno >= args.mp->m_sb.sb_agblocks) - return -EFSCORRUPTED; - args.pag = xfs_perag_get(args.mp, args.agno); ASSERT(args.pag); error = xfs_alloc_fix_freelist(&args, XFS_ALLOC_FLAG_FREEING); if (error) - goto error0; + goto out; + + *agbp = args.agbp; +out: + xfs_perag_put(args.pag); + return error; +} + +/* + * Free an extent. + * Just break up the extent address and hand off to xfs_free_ag_extent + * after fixing up the freelist. + */ +int /* error */ +xfs_free_extent( + struct xfs_trans *tp, /* transaction pointer */ + xfs_fsblock_t bno, /* starting block number of extent */ + xfs_extlen_t len, /* length of extent */ + struct xfs_owner_info *oinfo) /* extent owner */ +{ + struct xfs_mount *mp = tp->t_mountp; + struct xfs_buf *agbp; + xfs_agnumber_t agno = XFS_FSB_TO_AGNO(mp, bno); + xfs_agblock_t agbno = XFS_FSB_TO_AGBNO(mp, bno); + int error; + + ASSERT(len != 0); + + if (XFS_TEST_ERROR(false, mp, + XFS_ERRTAG_FREE_EXTENT, + XFS_RANDOM_FREE_EXTENT)) + return -EIO; + + error = xfs_free_extent_fix_freelist(tp, agno, &agbp); + if (error) + return error; + + XFS_WANT_CORRUPTED_GOTO(mp, agbno < mp->m_sb.sb_agblocks, err); /* validate the extent size is legal now we have the agf locked */ - if (args.agbno + len > - be32_to_cpu(XFS_BUF_TO_AGF(args.agbp)->agf_length)) { - error = -EFSCORRUPTED; - goto error0; - } + XFS_WANT_CORRUPTED_GOTO(mp, + agbno + len <= be32_to_cpu(XFS_BUF_TO_AGF(agbp)->agf_length), + err); - error = xfs_free_ag_extent(tp, args.agbp, args.agno, args.agbno, len, 0); - if (!error) - xfs_extent_busy_insert(tp, args.agno, args.agbno, len, 0); -error0: - xfs_perag_put(args.pag); + error = xfs_free_ag_extent(tp, agbp, agno, agbno, len, oinfo, 0); + if (error) + goto err; + + xfs_extent_busy_insert(tp, agno, agbno, len, 0); + return 0; + +err: + xfs_trans_brelse(tp, agbp); return error; } -- cgit v1.2.3-54-g00ecf