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-rw-r--r--module/zfs/dmu_traverse.c406
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diff --git a/module/zfs/dmu_traverse.c b/module/zfs/dmu_traverse.c
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+/*
+ * 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);
+}