diff options
Diffstat (limited to 'module/zfs/dmu_traverse.c')
-rw-r--r-- | module/zfs/dmu_traverse.c | 406 |
1 files changed, 406 insertions, 0 deletions
diff --git a/module/zfs/dmu_traverse.c b/module/zfs/dmu_traverse.c new file mode 100644 index 000000000..512401470 --- /dev/null +++ b/module/zfs/dmu_traverse.c @@ -0,0 +1,406 @@ +/* + * CDDL HEADER START + * + * The contents of this file are subject to the terms of the + * Common Development and Distribution License (the "License"). + * You may not use this file except in compliance with the License. + * + * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE + * or http://www.opensolaris.org/os/licensing. + * See the License for the specific language governing permissions + * and limitations under the License. + * + * When distributing Covered Code, include this CDDL HEADER in each + * file and include the License file at usr/src/OPENSOLARIS.LICENSE. + * If applicable, add the following below this CDDL HEADER, with the + * fields enclosed by brackets "[]" replaced with your own identifying + * information: Portions Copyright [yyyy] [name of copyright owner] + * + * CDDL HEADER END + */ +/* + * Copyright 2008 Sun Microsystems, Inc. All rights reserved. + * Use is subject to license terms. + */ + +#include <sys/zfs_context.h> +#include <sys/dmu_objset.h> +#include <sys/dmu_traverse.h> +#include <sys/dsl_dataset.h> +#include <sys/dsl_dir.h> +#include <sys/dsl_pool.h> +#include <sys/dnode.h> +#include <sys/spa.h> +#include <sys/zio.h> +#include <sys/dmu_impl.h> +#include <sys/callb.h> + +#define SET_BOOKMARK(zb, objset, object, level, blkid) \ +{ \ + (zb)->zb_objset = objset; \ + (zb)->zb_object = object; \ + (zb)->zb_level = level; \ + (zb)->zb_blkid = blkid; \ +} + +struct prefetch_data { + kmutex_t pd_mtx; + kcondvar_t pd_cv; + int pd_blks_max; + int pd_blks_fetched; + int pd_flags; + boolean_t pd_cancel; + boolean_t pd_exited; +}; + +struct traverse_data { + spa_t *td_spa; + uint64_t td_objset; + blkptr_t *td_rootbp; + uint64_t td_min_txg; + int td_flags; + struct prefetch_data *td_pfd; + blkptr_cb_t *td_func; + void *td_arg; +}; + +/* ARGSUSED */ +static void +traverse_zil_block(zilog_t *zilog, blkptr_t *bp, void *arg, uint64_t claim_txg) +{ + struct traverse_data *td = arg; + zbookmark_t zb; + + if (bp->blk_birth == 0) + return; + + if (claim_txg == 0 && bp->blk_birth >= spa_first_txg(td->td_spa)) + return; + + zb.zb_objset = td->td_objset; + zb.zb_object = 0; + zb.zb_level = -1; + zb.zb_blkid = bp->blk_cksum.zc_word[ZIL_ZC_SEQ]; + VERIFY(0 == td->td_func(td->td_spa, bp, &zb, NULL, td->td_arg)); +} + +/* ARGSUSED */ +static void +traverse_zil_record(zilog_t *zilog, lr_t *lrc, void *arg, uint64_t claim_txg) +{ + struct traverse_data *td = arg; + + if (lrc->lrc_txtype == TX_WRITE) { + lr_write_t *lr = (lr_write_t *)lrc; + blkptr_t *bp = &lr->lr_blkptr; + zbookmark_t zb; + + if (bp->blk_birth == 0) + return; + + if (claim_txg == 0 || bp->blk_birth < claim_txg) + return; + + zb.zb_objset = td->td_objset; + zb.zb_object = lr->lr_foid; + zb.zb_level = BP_GET_LEVEL(bp); + zb.zb_blkid = lr->lr_offset / BP_GET_LSIZE(bp); + VERIFY(0 == td->td_func(td->td_spa, bp, &zb, NULL, td->td_arg)); + } +} + +static void +traverse_zil(struct traverse_data *td, zil_header_t *zh) +{ + uint64_t claim_txg = zh->zh_claim_txg; + zilog_t *zilog; + + /* + * We only want to visit blocks that have been claimed but not yet + * replayed (or, in read-only mode, blocks that *would* be claimed). + */ + if (claim_txg == 0 && (spa_mode & FWRITE)) + return; + + zilog = zil_alloc(spa_get_dsl(td->td_spa)->dp_meta_objset, zh); + + (void) zil_parse(zilog, traverse_zil_block, traverse_zil_record, td, + claim_txg); + + zil_free(zilog); +} + +static int +traverse_visitbp(struct traverse_data *td, const dnode_phys_t *dnp, + arc_buf_t *pbuf, blkptr_t *bp, const zbookmark_t *zb) +{ + zbookmark_t czb; + int err = 0; + arc_buf_t *buf = NULL; + struct prefetch_data *pd = td->td_pfd; + + if (bp->blk_birth == 0) { + err = td->td_func(td->td_spa, NULL, zb, dnp, td->td_arg); + return (err); + } + + if (bp->blk_birth <= td->td_min_txg) + return (0); + + if (pd && !pd->pd_exited && + ((pd->pd_flags & TRAVERSE_PREFETCH_DATA) || + BP_GET_TYPE(bp) == DMU_OT_DNODE || BP_GET_LEVEL(bp) > 0)) { + mutex_enter(&pd->pd_mtx); + ASSERT(pd->pd_blks_fetched >= 0); + while (pd->pd_blks_fetched == 0 && !pd->pd_exited) + cv_wait(&pd->pd_cv, &pd->pd_mtx); + pd->pd_blks_fetched--; + cv_broadcast(&pd->pd_cv); + mutex_exit(&pd->pd_mtx); + } + + if (td->td_flags & TRAVERSE_PRE) { + err = td->td_func(td->td_spa, bp, zb, dnp, td->td_arg); + if (err) + return (err); + } + + if (BP_GET_LEVEL(bp) > 0) { + uint32_t flags = ARC_WAIT; + int i; + blkptr_t *cbp; + int epb = BP_GET_LSIZE(bp) >> SPA_BLKPTRSHIFT; + + err = arc_read(NULL, td->td_spa, bp, pbuf, + arc_getbuf_func, &buf, + ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL, &flags, zb); + if (err) + return (err); + + /* recursively visitbp() blocks below this */ + cbp = buf->b_data; + for (i = 0; i < epb; i++, cbp++) { + SET_BOOKMARK(&czb, zb->zb_objset, zb->zb_object, + zb->zb_level - 1, + zb->zb_blkid * epb + i); + err = traverse_visitbp(td, dnp, buf, cbp, &czb); + if (err) + break; + } + } else if (BP_GET_TYPE(bp) == DMU_OT_DNODE) { + uint32_t flags = ARC_WAIT; + int i, j; + int epb = BP_GET_LSIZE(bp) >> DNODE_SHIFT; + + err = arc_read(NULL, td->td_spa, bp, pbuf, + arc_getbuf_func, &buf, + ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL, &flags, zb); + if (err) + return (err); + + /* recursively visitbp() blocks below this */ + dnp = buf->b_data; + for (i = 0; i < epb && err == 0; i++, dnp++) { + for (j = 0; j < dnp->dn_nblkptr; j++) { + SET_BOOKMARK(&czb, zb->zb_objset, + zb->zb_blkid * epb + i, + dnp->dn_nlevels - 1, j); + err = traverse_visitbp(td, dnp, buf, + (blkptr_t *)&dnp->dn_blkptr[j], &czb); + if (err) + break; + } + } + } else if (BP_GET_TYPE(bp) == DMU_OT_OBJSET) { + uint32_t flags = ARC_WAIT; + objset_phys_t *osp; + int j; + + err = arc_read_nolock(NULL, td->td_spa, bp, + arc_getbuf_func, &buf, + ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL, &flags, zb); + if (err) + return (err); + + osp = buf->b_data; + /* + * traverse_zil is just here for zdb's leak checking. + * For other consumers, there will be no ZIL blocks. + */ + traverse_zil(td, &osp->os_zil_header); + + for (j = 0; j < osp->os_meta_dnode.dn_nblkptr; j++) { + SET_BOOKMARK(&czb, zb->zb_objset, 0, + osp->os_meta_dnode.dn_nlevels - 1, j); + err = traverse_visitbp(td, &osp->os_meta_dnode, buf, + (blkptr_t *)&osp->os_meta_dnode.dn_blkptr[j], + &czb); + if (err) + break; + } + } + + if (buf) + (void) arc_buf_remove_ref(buf, &buf); + + if (err == 0 && (td->td_flags & TRAVERSE_POST)) + err = td->td_func(td->td_spa, bp, zb, dnp, td->td_arg); + + return (err); +} + +/* ARGSUSED */ +static int +traverse_prefetcher(spa_t *spa, blkptr_t *bp, const zbookmark_t *zb, + const dnode_phys_t *dnp, void *arg) +{ + struct prefetch_data *pfd = arg; + uint32_t aflags = ARC_NOWAIT | ARC_PREFETCH; + + ASSERT(pfd->pd_blks_fetched >= 0); + if (pfd->pd_cancel) + return (EINTR); + + if (bp == NULL || !((pfd->pd_flags & TRAVERSE_PREFETCH_DATA) || + BP_GET_TYPE(bp) == DMU_OT_DNODE || BP_GET_LEVEL(bp) > 0)) + return (0); + + mutex_enter(&pfd->pd_mtx); + while (!pfd->pd_cancel && pfd->pd_blks_fetched >= pfd->pd_blks_max) + cv_wait(&pfd->pd_cv, &pfd->pd_mtx); + pfd->pd_blks_fetched++; + cv_broadcast(&pfd->pd_cv); + mutex_exit(&pfd->pd_mtx); + + (void) arc_read_nolock(NULL, spa, bp, NULL, NULL, + ZIO_PRIORITY_ASYNC_READ, + ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE, + &aflags, zb); + + return (0); +} + +static void +traverse_prefetch_thread(void *arg) +{ + struct traverse_data *td_main = arg; + struct traverse_data td = *td_main; + zbookmark_t czb; + + td.td_func = traverse_prefetcher; + td.td_arg = td_main->td_pfd; + td.td_pfd = NULL; + + SET_BOOKMARK(&czb, td.td_objset, 0, -1, 0); + (void) traverse_visitbp(&td, NULL, NULL, td.td_rootbp, &czb); + + mutex_enter(&td_main->td_pfd->pd_mtx); + td_main->td_pfd->pd_exited = B_TRUE; + cv_broadcast(&td_main->td_pfd->pd_cv); + mutex_exit(&td_main->td_pfd->pd_mtx); +} + +/* + * NB: dataset must not be changing on-disk (eg, is a snapshot or we are + * in syncing context). + */ +static int +traverse_impl(spa_t *spa, uint64_t objset, blkptr_t *rootbp, + uint64_t txg_start, int flags, blkptr_cb_t func, void *arg) +{ + struct traverse_data td; + struct prefetch_data pd = { 0 }; + zbookmark_t czb; + int err; + + td.td_spa = spa; + td.td_objset = objset; + td.td_rootbp = rootbp; + td.td_min_txg = txg_start; + td.td_func = func; + td.td_arg = arg; + td.td_pfd = &pd; + td.td_flags = flags; + + pd.pd_blks_max = 100; + pd.pd_flags = flags; + mutex_init(&pd.pd_mtx, NULL, MUTEX_DEFAULT, NULL); + cv_init(&pd.pd_cv, NULL, CV_DEFAULT, NULL); + + if (!(flags & TRAVERSE_PREFETCH) || + 0 == taskq_dispatch(system_taskq, traverse_prefetch_thread, + &td, TQ_NOQUEUE)) + pd.pd_exited = B_TRUE; + + SET_BOOKMARK(&czb, objset, 0, -1, 0); + err = traverse_visitbp(&td, NULL, NULL, rootbp, &czb); + + mutex_enter(&pd.pd_mtx); + pd.pd_cancel = B_TRUE; + cv_broadcast(&pd.pd_cv); + while (!pd.pd_exited) + cv_wait(&pd.pd_cv, &pd.pd_mtx); + mutex_exit(&pd.pd_mtx); + + mutex_destroy(&pd.pd_mtx); + cv_destroy(&pd.pd_cv); + + return (err); +} + +/* + * NB: dataset must not be changing on-disk (eg, is a snapshot or we are + * in syncing context). + */ +int +traverse_dataset(dsl_dataset_t *ds, uint64_t txg_start, int flags, + blkptr_cb_t func, void *arg) +{ + return (traverse_impl(ds->ds_dir->dd_pool->dp_spa, ds->ds_object, + &ds->ds_phys->ds_bp, txg_start, flags, func, arg)); +} + +/* + * NB: pool must not be changing on-disk (eg, from zdb or sync context). + */ +int +traverse_pool(spa_t *spa, blkptr_cb_t func, void *arg) +{ + int err; + uint64_t obj; + dsl_pool_t *dp = spa_get_dsl(spa); + objset_t *mos = dp->dp_meta_objset; + + /* visit the MOS */ + err = traverse_impl(spa, 0, spa_get_rootblkptr(spa), + 0, TRAVERSE_PRE, func, arg); + if (err) + return (err); + + /* visit each dataset */ + for (obj = 1; err == 0; err = dmu_object_next(mos, &obj, FALSE, 0)) { + dmu_object_info_t doi; + + err = dmu_object_info(mos, obj, &doi); + if (err) + return (err); + + if (doi.doi_type == DMU_OT_DSL_DATASET) { + dsl_dataset_t *ds; + rw_enter(&dp->dp_config_rwlock, RW_READER); + err = dsl_dataset_hold_obj(dp, obj, FTAG, &ds); + rw_exit(&dp->dp_config_rwlock); + if (err) + return (err); + err = traverse_dataset(ds, + ds->ds_phys->ds_prev_snap_txg, TRAVERSE_PRE, + func, arg); + dsl_dataset_rele(ds, FTAG); + if (err) + return (err); + } + } + if (err == ESRCH) + err = 0; + return (err); +} |