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-rw-r--r--uts/common/fs/zfs/dnode.c1993
1 files changed, 1993 insertions, 0 deletions
diff --git a/uts/common/fs/zfs/dnode.c b/uts/common/fs/zfs/dnode.c
new file mode 100644
index 000000000000..850dd5816bf3
--- /dev/null
+++ b/uts/common/fs/zfs/dnode.c
@@ -0,0 +1,1993 @@
+/*
+ * 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 (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
+ */
+
+#include <sys/zfs_context.h>
+#include <sys/dbuf.h>
+#include <sys/dnode.h>
+#include <sys/dmu.h>
+#include <sys/dmu_impl.h>
+#include <sys/dmu_tx.h>
+#include <sys/dmu_objset.h>
+#include <sys/dsl_dir.h>
+#include <sys/dsl_dataset.h>
+#include <sys/spa.h>
+#include <sys/zio.h>
+#include <sys/dmu_zfetch.h>
+
+static int free_range_compar(const void *node1, const void *node2);
+
+static kmem_cache_t *dnode_cache;
+/*
+ * Define DNODE_STATS to turn on statistic gathering. By default, it is only
+ * turned on when DEBUG is also defined.
+ */
+#ifdef DEBUG
+#define DNODE_STATS
+#endif /* DEBUG */
+
+#ifdef DNODE_STATS
+#define DNODE_STAT_ADD(stat) ((stat)++)
+#else
+#define DNODE_STAT_ADD(stat) /* nothing */
+#endif /* DNODE_STATS */
+
+static dnode_phys_t dnode_phys_zero;
+
+int zfs_default_bs = SPA_MINBLOCKSHIFT;
+int zfs_default_ibs = DN_MAX_INDBLKSHIFT;
+
+static kmem_cbrc_t dnode_move(void *, void *, size_t, void *);
+
+/* ARGSUSED */
+static int
+dnode_cons(void *arg, void *unused, int kmflag)
+{
+ dnode_t *dn = arg;
+ int i;
+
+ rw_init(&dn->dn_struct_rwlock, NULL, RW_DEFAULT, NULL);
+ mutex_init(&dn->dn_mtx, NULL, MUTEX_DEFAULT, NULL);
+ mutex_init(&dn->dn_dbufs_mtx, NULL, MUTEX_DEFAULT, NULL);
+ cv_init(&dn->dn_notxholds, NULL, CV_DEFAULT, NULL);
+
+ refcount_create(&dn->dn_holds);
+ refcount_create(&dn->dn_tx_holds);
+ list_link_init(&dn->dn_link);
+
+ bzero(&dn->dn_next_nblkptr[0], sizeof (dn->dn_next_nblkptr));
+ bzero(&dn->dn_next_nlevels[0], sizeof (dn->dn_next_nlevels));
+ bzero(&dn->dn_next_indblkshift[0], sizeof (dn->dn_next_indblkshift));
+ bzero(&dn->dn_next_bonustype[0], sizeof (dn->dn_next_bonustype));
+ bzero(&dn->dn_rm_spillblk[0], sizeof (dn->dn_rm_spillblk));
+ bzero(&dn->dn_next_bonuslen[0], sizeof (dn->dn_next_bonuslen));
+ bzero(&dn->dn_next_blksz[0], sizeof (dn->dn_next_blksz));
+
+ for (i = 0; i < TXG_SIZE; i++) {
+ list_link_init(&dn->dn_dirty_link[i]);
+ avl_create(&dn->dn_ranges[i], free_range_compar,
+ sizeof (free_range_t),
+ offsetof(struct free_range, fr_node));
+ list_create(&dn->dn_dirty_records[i],
+ sizeof (dbuf_dirty_record_t),
+ offsetof(dbuf_dirty_record_t, dr_dirty_node));
+ }
+
+ dn->dn_allocated_txg = 0;
+ dn->dn_free_txg = 0;
+ dn->dn_assigned_txg = 0;
+ dn->dn_dirtyctx = 0;
+ dn->dn_dirtyctx_firstset = NULL;
+ dn->dn_bonus = NULL;
+ dn->dn_have_spill = B_FALSE;
+ dn->dn_zio = NULL;
+ dn->dn_oldused = 0;
+ dn->dn_oldflags = 0;
+ dn->dn_olduid = 0;
+ dn->dn_oldgid = 0;
+ dn->dn_newuid = 0;
+ dn->dn_newgid = 0;
+ dn->dn_id_flags = 0;
+
+ dn->dn_dbufs_count = 0;
+ list_create(&dn->dn_dbufs, sizeof (dmu_buf_impl_t),
+ offsetof(dmu_buf_impl_t, db_link));
+
+ dn->dn_moved = 0;
+ return (0);
+}
+
+/* ARGSUSED */
+static void
+dnode_dest(void *arg, void *unused)
+{
+ int i;
+ dnode_t *dn = arg;
+
+ rw_destroy(&dn->dn_struct_rwlock);
+ mutex_destroy(&dn->dn_mtx);
+ mutex_destroy(&dn->dn_dbufs_mtx);
+ cv_destroy(&dn->dn_notxholds);
+ refcount_destroy(&dn->dn_holds);
+ refcount_destroy(&dn->dn_tx_holds);
+ ASSERT(!list_link_active(&dn->dn_link));
+
+ for (i = 0; i < TXG_SIZE; i++) {
+ ASSERT(!list_link_active(&dn->dn_dirty_link[i]));
+ avl_destroy(&dn->dn_ranges[i]);
+ list_destroy(&dn->dn_dirty_records[i]);
+ ASSERT3U(dn->dn_next_nblkptr[i], ==, 0);
+ ASSERT3U(dn->dn_next_nlevels[i], ==, 0);
+ ASSERT3U(dn->dn_next_indblkshift[i], ==, 0);
+ ASSERT3U(dn->dn_next_bonustype[i], ==, 0);
+ ASSERT3U(dn->dn_rm_spillblk[i], ==, 0);
+ ASSERT3U(dn->dn_next_bonuslen[i], ==, 0);
+ ASSERT3U(dn->dn_next_blksz[i], ==, 0);
+ }
+
+ ASSERT3U(dn->dn_allocated_txg, ==, 0);
+ ASSERT3U(dn->dn_free_txg, ==, 0);
+ ASSERT3U(dn->dn_assigned_txg, ==, 0);
+ ASSERT3U(dn->dn_dirtyctx, ==, 0);
+ ASSERT3P(dn->dn_dirtyctx_firstset, ==, NULL);
+ ASSERT3P(dn->dn_bonus, ==, NULL);
+ ASSERT(!dn->dn_have_spill);
+ ASSERT3P(dn->dn_zio, ==, NULL);
+ ASSERT3U(dn->dn_oldused, ==, 0);
+ ASSERT3U(dn->dn_oldflags, ==, 0);
+ ASSERT3U(dn->dn_olduid, ==, 0);
+ ASSERT3U(dn->dn_oldgid, ==, 0);
+ ASSERT3U(dn->dn_newuid, ==, 0);
+ ASSERT3U(dn->dn_newgid, ==, 0);
+ ASSERT3U(dn->dn_id_flags, ==, 0);
+
+ ASSERT3U(dn->dn_dbufs_count, ==, 0);
+ list_destroy(&dn->dn_dbufs);
+}
+
+void
+dnode_init(void)
+{
+ ASSERT(dnode_cache == NULL);
+ dnode_cache = kmem_cache_create("dnode_t",
+ sizeof (dnode_t),
+ 0, dnode_cons, dnode_dest, NULL, NULL, NULL, 0);
+ kmem_cache_set_move(dnode_cache, dnode_move);
+}
+
+void
+dnode_fini(void)
+{
+ kmem_cache_destroy(dnode_cache);
+ dnode_cache = NULL;
+}
+
+
+#ifdef ZFS_DEBUG
+void
+dnode_verify(dnode_t *dn)
+{
+ int drop_struct_lock = FALSE;
+
+ ASSERT(dn->dn_phys);
+ ASSERT(dn->dn_objset);
+ ASSERT(dn->dn_handle->dnh_dnode == dn);
+
+ ASSERT(dn->dn_phys->dn_type < DMU_OT_NUMTYPES);
+
+ if (!(zfs_flags & ZFS_DEBUG_DNODE_VERIFY))
+ return;
+
+ if (!RW_WRITE_HELD(&dn->dn_struct_rwlock)) {
+ rw_enter(&dn->dn_struct_rwlock, RW_READER);
+ drop_struct_lock = TRUE;
+ }
+ if (dn->dn_phys->dn_type != DMU_OT_NONE || dn->dn_allocated_txg != 0) {
+ int i;
+ ASSERT3U(dn->dn_indblkshift, >=, 0);
+ ASSERT3U(dn->dn_indblkshift, <=, SPA_MAXBLOCKSHIFT);
+ if (dn->dn_datablkshift) {
+ ASSERT3U(dn->dn_datablkshift, >=, SPA_MINBLOCKSHIFT);
+ ASSERT3U(dn->dn_datablkshift, <=, SPA_MAXBLOCKSHIFT);
+ ASSERT3U(1<<dn->dn_datablkshift, ==, dn->dn_datablksz);
+ }
+ ASSERT3U(dn->dn_nlevels, <=, 30);
+ ASSERT3U(dn->dn_type, <=, DMU_OT_NUMTYPES);
+ ASSERT3U(dn->dn_nblkptr, >=, 1);
+ ASSERT3U(dn->dn_nblkptr, <=, DN_MAX_NBLKPTR);
+ ASSERT3U(dn->dn_bonuslen, <=, DN_MAX_BONUSLEN);
+ ASSERT3U(dn->dn_datablksz, ==,
+ dn->dn_datablkszsec << SPA_MINBLOCKSHIFT);
+ ASSERT3U(ISP2(dn->dn_datablksz), ==, dn->dn_datablkshift != 0);
+ ASSERT3U((dn->dn_nblkptr - 1) * sizeof (blkptr_t) +
+ dn->dn_bonuslen, <=, DN_MAX_BONUSLEN);
+ for (i = 0; i < TXG_SIZE; i++) {
+ ASSERT3U(dn->dn_next_nlevels[i], <=, dn->dn_nlevels);
+ }
+ }
+ if (dn->dn_phys->dn_type != DMU_OT_NONE)
+ ASSERT3U(dn->dn_phys->dn_nlevels, <=, dn->dn_nlevels);
+ ASSERT(DMU_OBJECT_IS_SPECIAL(dn->dn_object) || dn->dn_dbuf != NULL);
+ if (dn->dn_dbuf != NULL) {
+ ASSERT3P(dn->dn_phys, ==,
+ (dnode_phys_t *)dn->dn_dbuf->db.db_data +
+ (dn->dn_object % (dn->dn_dbuf->db.db_size >> DNODE_SHIFT)));
+ }
+ if (drop_struct_lock)
+ rw_exit(&dn->dn_struct_rwlock);
+}
+#endif
+
+void
+dnode_byteswap(dnode_phys_t *dnp)
+{
+ uint64_t *buf64 = (void*)&dnp->dn_blkptr;
+ int i;
+
+ if (dnp->dn_type == DMU_OT_NONE) {
+ bzero(dnp, sizeof (dnode_phys_t));
+ return;
+ }
+
+ dnp->dn_datablkszsec = BSWAP_16(dnp->dn_datablkszsec);
+ dnp->dn_bonuslen = BSWAP_16(dnp->dn_bonuslen);
+ dnp->dn_maxblkid = BSWAP_64(dnp->dn_maxblkid);
+ dnp->dn_used = BSWAP_64(dnp->dn_used);
+
+ /*
+ * dn_nblkptr is only one byte, so it's OK to read it in either
+ * byte order. We can't read dn_bouslen.
+ */
+ ASSERT(dnp->dn_indblkshift <= SPA_MAXBLOCKSHIFT);
+ ASSERT(dnp->dn_nblkptr <= DN_MAX_NBLKPTR);
+ for (i = 0; i < dnp->dn_nblkptr * sizeof (blkptr_t)/8; i++)
+ buf64[i] = BSWAP_64(buf64[i]);
+
+ /*
+ * OK to check dn_bonuslen for zero, because it won't matter if
+ * we have the wrong byte order. This is necessary because the
+ * dnode dnode is smaller than a regular dnode.
+ */
+ if (dnp->dn_bonuslen != 0) {
+ /*
+ * Note that the bonus length calculated here may be
+ * longer than the actual bonus buffer. This is because
+ * we always put the bonus buffer after the last block
+ * pointer (instead of packing it against the end of the
+ * dnode buffer).
+ */
+ int off = (dnp->dn_nblkptr-1) * sizeof (blkptr_t);
+ size_t len = DN_MAX_BONUSLEN - off;
+ ASSERT3U(dnp->dn_bonustype, <, DMU_OT_NUMTYPES);
+ dmu_ot[dnp->dn_bonustype].ot_byteswap(dnp->dn_bonus + off, len);
+ }
+
+ /* Swap SPILL block if we have one */
+ if (dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR)
+ byteswap_uint64_array(&dnp->dn_spill, sizeof (blkptr_t));
+
+}
+
+void
+dnode_buf_byteswap(void *vbuf, size_t size)
+{
+ dnode_phys_t *buf = vbuf;
+ int i;
+
+ ASSERT3U(sizeof (dnode_phys_t), ==, (1<<DNODE_SHIFT));
+ ASSERT((size & (sizeof (dnode_phys_t)-1)) == 0);
+
+ size >>= DNODE_SHIFT;
+ for (i = 0; i < size; i++) {
+ dnode_byteswap(buf);
+ buf++;
+ }
+}
+
+static int
+free_range_compar(const void *node1, const void *node2)
+{
+ const free_range_t *rp1 = node1;
+ const free_range_t *rp2 = node2;
+
+ if (rp1->fr_blkid < rp2->fr_blkid)
+ return (-1);
+ else if (rp1->fr_blkid > rp2->fr_blkid)
+ return (1);
+ else return (0);
+}
+
+void
+dnode_setbonuslen(dnode_t *dn, int newsize, dmu_tx_t *tx)
+{
+ ASSERT3U(refcount_count(&dn->dn_holds), >=, 1);
+
+ dnode_setdirty(dn, tx);
+ rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
+ ASSERT3U(newsize, <=, DN_MAX_BONUSLEN -
+ (dn->dn_nblkptr-1) * sizeof (blkptr_t));
+ dn->dn_bonuslen = newsize;
+ if (newsize == 0)
+ dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = DN_ZERO_BONUSLEN;
+ else
+ dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = dn->dn_bonuslen;
+ rw_exit(&dn->dn_struct_rwlock);
+}
+
+void
+dnode_setbonus_type(dnode_t *dn, dmu_object_type_t newtype, dmu_tx_t *tx)
+{
+ ASSERT3U(refcount_count(&dn->dn_holds), >=, 1);
+ dnode_setdirty(dn, tx);
+ rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
+ dn->dn_bonustype = newtype;
+ dn->dn_next_bonustype[tx->tx_txg & TXG_MASK] = dn->dn_bonustype;
+ rw_exit(&dn->dn_struct_rwlock);
+}
+
+void
+dnode_rm_spill(dnode_t *dn, dmu_tx_t *tx)
+{
+ ASSERT3U(refcount_count(&dn->dn_holds), >=, 1);
+ ASSERT(RW_WRITE_HELD(&dn->dn_struct_rwlock));
+ dnode_setdirty(dn, tx);
+ dn->dn_rm_spillblk[tx->tx_txg&TXG_MASK] = DN_KILL_SPILLBLK;
+ dn->dn_have_spill = B_FALSE;
+}
+
+static void
+dnode_setdblksz(dnode_t *dn, int size)
+{
+ ASSERT3U(P2PHASE(size, SPA_MINBLOCKSIZE), ==, 0);
+ ASSERT3U(size, <=, SPA_MAXBLOCKSIZE);
+ ASSERT3U(size, >=, SPA_MINBLOCKSIZE);
+ ASSERT3U(size >> SPA_MINBLOCKSHIFT, <,
+ 1<<(sizeof (dn->dn_phys->dn_datablkszsec) * 8));
+ dn->dn_datablksz = size;
+ dn->dn_datablkszsec = size >> SPA_MINBLOCKSHIFT;
+ dn->dn_datablkshift = ISP2(size) ? highbit(size - 1) : 0;
+}
+
+static dnode_t *
+dnode_create(objset_t *os, dnode_phys_t *dnp, dmu_buf_impl_t *db,
+ uint64_t object, dnode_handle_t *dnh)
+{
+ dnode_t *dn = kmem_cache_alloc(dnode_cache, KM_SLEEP);
+
+ ASSERT(!POINTER_IS_VALID(dn->dn_objset));
+ dn->dn_moved = 0;
+
+ /*
+ * Defer setting dn_objset until the dnode is ready to be a candidate
+ * for the dnode_move() callback.
+ */
+ dn->dn_object = object;
+ dn->dn_dbuf = db;
+ dn->dn_handle = dnh;
+ dn->dn_phys = dnp;
+
+ if (dnp->dn_datablkszsec) {
+ dnode_setdblksz(dn, dnp->dn_datablkszsec << SPA_MINBLOCKSHIFT);
+ } else {
+ dn->dn_datablksz = 0;
+ dn->dn_datablkszsec = 0;
+ dn->dn_datablkshift = 0;
+ }
+ dn->dn_indblkshift = dnp->dn_indblkshift;
+ dn->dn_nlevels = dnp->dn_nlevels;
+ dn->dn_type = dnp->dn_type;
+ dn->dn_nblkptr = dnp->dn_nblkptr;
+ dn->dn_checksum = dnp->dn_checksum;
+ dn->dn_compress = dnp->dn_compress;
+ dn->dn_bonustype = dnp->dn_bonustype;
+ dn->dn_bonuslen = dnp->dn_bonuslen;
+ dn->dn_maxblkid = dnp->dn_maxblkid;
+ dn->dn_have_spill = ((dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR) != 0);
+ dn->dn_id_flags = 0;
+
+ dmu_zfetch_init(&dn->dn_zfetch, dn);
+
+ ASSERT(dn->dn_phys->dn_type < DMU_OT_NUMTYPES);
+
+ mutex_enter(&os->os_lock);
+ list_insert_head(&os->os_dnodes, dn);
+ membar_producer();
+ /*
+ * Everything else must be valid before assigning dn_objset makes the
+ * dnode eligible for dnode_move().
+ */
+ dn->dn_objset = os;
+ mutex_exit(&os->os_lock);
+
+ arc_space_consume(sizeof (dnode_t), ARC_SPACE_OTHER);
+ return (dn);
+}
+
+/*
+ * Caller must be holding the dnode handle, which is released upon return.
+ */
+static void
+dnode_destroy(dnode_t *dn)
+{
+ objset_t *os = dn->dn_objset;
+
+ ASSERT((dn->dn_id_flags & DN_ID_NEW_EXIST) == 0);
+
+ mutex_enter(&os->os_lock);
+ POINTER_INVALIDATE(&dn->dn_objset);
+ list_remove(&os->os_dnodes, dn);
+ mutex_exit(&os->os_lock);
+
+ /* the dnode can no longer move, so we can release the handle */
+ zrl_remove(&dn->dn_handle->dnh_zrlock);
+
+ dn->dn_allocated_txg = 0;
+ dn->dn_free_txg = 0;
+ dn->dn_assigned_txg = 0;
+
+ dn->dn_dirtyctx = 0;
+ if (dn->dn_dirtyctx_firstset != NULL) {
+ kmem_free(dn->dn_dirtyctx_firstset, 1);
+ dn->dn_dirtyctx_firstset = NULL;
+ }
+ if (dn->dn_bonus != NULL) {
+ mutex_enter(&dn->dn_bonus->db_mtx);
+ dbuf_evict(dn->dn_bonus);
+ dn->dn_bonus = NULL;
+ }
+ dn->dn_zio = NULL;
+
+ dn->dn_have_spill = B_FALSE;
+ dn->dn_oldused = 0;
+ dn->dn_oldflags = 0;
+ dn->dn_olduid = 0;
+ dn->dn_oldgid = 0;
+ dn->dn_newuid = 0;
+ dn->dn_newgid = 0;
+ dn->dn_id_flags = 0;
+
+ dmu_zfetch_rele(&dn->dn_zfetch);
+ kmem_cache_free(dnode_cache, dn);
+ arc_space_return(sizeof (dnode_t), ARC_SPACE_OTHER);
+}
+
+void
+dnode_allocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, int ibs,
+ dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx)
+{
+ int i;
+
+ if (blocksize == 0)
+ blocksize = 1 << zfs_default_bs;
+ else if (blocksize > SPA_MAXBLOCKSIZE)
+ blocksize = SPA_MAXBLOCKSIZE;
+ else
+ blocksize = P2ROUNDUP(blocksize, SPA_MINBLOCKSIZE);
+
+ if (ibs == 0)
+ ibs = zfs_default_ibs;
+
+ ibs = MIN(MAX(ibs, DN_MIN_INDBLKSHIFT), DN_MAX_INDBLKSHIFT);
+
+ dprintf("os=%p obj=%llu txg=%llu blocksize=%d ibs=%d\n", dn->dn_objset,
+ dn->dn_object, tx->tx_txg, blocksize, ibs);
+
+ ASSERT(dn->dn_type == DMU_OT_NONE);
+ ASSERT(bcmp(dn->dn_phys, &dnode_phys_zero, sizeof (dnode_phys_t)) == 0);
+ ASSERT(dn->dn_phys->dn_type == DMU_OT_NONE);
+ ASSERT(ot != DMU_OT_NONE);
+ ASSERT3U(ot, <, DMU_OT_NUMTYPES);
+ ASSERT((bonustype == DMU_OT_NONE && bonuslen == 0) ||
+ (bonustype == DMU_OT_SA && bonuslen == 0) ||
+ (bonustype != DMU_OT_NONE && bonuslen != 0));
+ ASSERT3U(bonustype, <, DMU_OT_NUMTYPES);
+ ASSERT3U(bonuslen, <=, DN_MAX_BONUSLEN);
+ ASSERT(dn->dn_type == DMU_OT_NONE);
+ ASSERT3U(dn->dn_maxblkid, ==, 0);
+ ASSERT3U(dn->dn_allocated_txg, ==, 0);
+ ASSERT3U(dn->dn_assigned_txg, ==, 0);
+ ASSERT(refcount_is_zero(&dn->dn_tx_holds));
+ ASSERT3U(refcount_count(&dn->dn_holds), <=, 1);
+ ASSERT3P(list_head(&dn->dn_dbufs), ==, NULL);
+
+ for (i = 0; i < TXG_SIZE; i++) {
+ ASSERT3U(dn->dn_next_nblkptr[i], ==, 0);
+ ASSERT3U(dn->dn_next_nlevels[i], ==, 0);
+ ASSERT3U(dn->dn_next_indblkshift[i], ==, 0);
+ ASSERT3U(dn->dn_next_bonuslen[i], ==, 0);
+ ASSERT3U(dn->dn_next_bonustype[i], ==, 0);
+ ASSERT3U(dn->dn_rm_spillblk[i], ==, 0);
+ ASSERT3U(dn->dn_next_blksz[i], ==, 0);
+ ASSERT(!list_link_active(&dn->dn_dirty_link[i]));
+ ASSERT3P(list_head(&dn->dn_dirty_records[i]), ==, NULL);
+ ASSERT3U(avl_numnodes(&dn->dn_ranges[i]), ==, 0);
+ }
+
+ dn->dn_type = ot;
+ dnode_setdblksz(dn, blocksize);
+ dn->dn_indblkshift = ibs;
+ dn->dn_nlevels = 1;
+ if (bonustype == DMU_OT_SA) /* Maximize bonus space for SA */
+ dn->dn_nblkptr = 1;
+ else
+ dn->dn_nblkptr = 1 +
+ ((DN_MAX_BONUSLEN - bonuslen) >> SPA_BLKPTRSHIFT);
+ dn->dn_bonustype = bonustype;
+ dn->dn_bonuslen = bonuslen;
+ dn->dn_checksum = ZIO_CHECKSUM_INHERIT;
+ dn->dn_compress = ZIO_COMPRESS_INHERIT;
+ dn->dn_dirtyctx = 0;
+
+ dn->dn_free_txg = 0;
+ if (dn->dn_dirtyctx_firstset) {
+ kmem_free(dn->dn_dirtyctx_firstset, 1);
+ dn->dn_dirtyctx_firstset = NULL;
+ }
+
+ dn->dn_allocated_txg = tx->tx_txg;
+ dn->dn_id_flags = 0;
+
+ dnode_setdirty(dn, tx);
+ dn->dn_next_indblkshift[tx->tx_txg & TXG_MASK] = ibs;
+ dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = dn->dn_bonuslen;
+ dn->dn_next_bonustype[tx->tx_txg & TXG_MASK] = dn->dn_bonustype;
+ dn->dn_next_blksz[tx->tx_txg & TXG_MASK] = dn->dn_datablksz;
+}
+
+void
+dnode_reallocate(dnode_t *dn, dmu_object_type_t ot, int blocksize,
+ dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx)
+{
+ int nblkptr;
+
+ ASSERT3U(blocksize, >=, SPA_MINBLOCKSIZE);
+ ASSERT3U(blocksize, <=, SPA_MAXBLOCKSIZE);
+ ASSERT3U(blocksize % SPA_MINBLOCKSIZE, ==, 0);
+ ASSERT(dn->dn_object != DMU_META_DNODE_OBJECT || dmu_tx_private_ok(tx));
+ ASSERT(tx->tx_txg != 0);
+ ASSERT((bonustype == DMU_OT_NONE && bonuslen == 0) ||
+ (bonustype != DMU_OT_NONE && bonuslen != 0) ||
+ (bonustype == DMU_OT_SA && bonuslen == 0));
+ ASSERT3U(bonustype, <, DMU_OT_NUMTYPES);
+ ASSERT3U(bonuslen, <=, DN_MAX_BONUSLEN);
+
+ /* clean up any unreferenced dbufs */
+ dnode_evict_dbufs(dn);
+
+ dn->dn_id_flags = 0;
+
+ rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
+ dnode_setdirty(dn, tx);
+ if (dn->dn_datablksz != blocksize) {
+ /* change blocksize */
+ ASSERT(dn->dn_maxblkid == 0 &&
+ (BP_IS_HOLE(&dn->dn_phys->dn_blkptr[0]) ||
+ dnode_block_freed(dn, 0)));
+ dnode_setdblksz(dn, blocksize);
+ dn->dn_next_blksz[tx->tx_txg&TXG_MASK] = blocksize;
+ }
+ if (dn->dn_bonuslen != bonuslen)
+ dn->dn_next_bonuslen[tx->tx_txg&TXG_MASK] = bonuslen;
+
+ if (bonustype == DMU_OT_SA) /* Maximize bonus space for SA */
+ nblkptr = 1;
+ else
+ nblkptr = 1 + ((DN_MAX_BONUSLEN - bonuslen) >> SPA_BLKPTRSHIFT);
+ if (dn->dn_bonustype != bonustype)
+ dn->dn_next_bonustype[tx->tx_txg&TXG_MASK] = bonustype;
+ if (dn->dn_nblkptr != nblkptr)
+ dn->dn_next_nblkptr[tx->tx_txg&TXG_MASK] = nblkptr;
+ if (dn->dn_phys->dn_flags & DNODE_FLAG_SPILL_BLKPTR) {
+ dbuf_rm_spill(dn, tx);
+ dnode_rm_spill(dn, tx);
+ }
+ rw_exit(&dn->dn_struct_rwlock);
+
+ /* change type */
+ dn->dn_type = ot;
+
+ /* change bonus size and type */
+ mutex_enter(&dn->dn_mtx);
+ dn->dn_bonustype = bonustype;
+ dn->dn_bonuslen = bonuslen;
+ dn->dn_nblkptr = nblkptr;
+ dn->dn_checksum = ZIO_CHECKSUM_INHERIT;
+ dn->dn_compress = ZIO_COMPRESS_INHERIT;
+ ASSERT3U(dn->dn_nblkptr, <=, DN_MAX_NBLKPTR);
+
+ /* fix up the bonus db_size */
+ if (dn->dn_bonus) {
+ dn->dn_bonus->db.db_size =
+ DN_MAX_BONUSLEN - (dn->dn_nblkptr-1) * sizeof (blkptr_t);
+ ASSERT(dn->dn_bonuslen <= dn->dn_bonus->db.db_size);
+ }
+
+ dn->dn_allocated_txg = tx->tx_txg;
+ mutex_exit(&dn->dn_mtx);
+}
+
+#ifdef DNODE_STATS
+static struct {
+ uint64_t dms_dnode_invalid;
+ uint64_t dms_dnode_recheck1;
+ uint64_t dms_dnode_recheck2;
+ uint64_t dms_dnode_special;
+ uint64_t dms_dnode_handle;
+ uint64_t dms_dnode_rwlock;
+ uint64_t dms_dnode_active;
+} dnode_move_stats;
+#endif /* DNODE_STATS */
+
+static void
+dnode_move_impl(dnode_t *odn, dnode_t *ndn)
+{
+ int i;
+
+ ASSERT(!RW_LOCK_HELD(&odn->dn_struct_rwlock));
+ ASSERT(MUTEX_NOT_HELD(&odn->dn_mtx));
+ ASSERT(MUTEX_NOT_HELD(&odn->dn_dbufs_mtx));
+ ASSERT(!RW_LOCK_HELD(&odn->dn_zfetch.zf_rwlock));
+
+ /* Copy fields. */
+ ndn->dn_objset = odn->dn_objset;
+ ndn->dn_object = odn->dn_object;
+ ndn->dn_dbuf = odn->dn_dbuf;
+ ndn->dn_handle = odn->dn_handle;
+ ndn->dn_phys = odn->dn_phys;
+ ndn->dn_type = odn->dn_type;
+ ndn->dn_bonuslen = odn->dn_bonuslen;
+ ndn->dn_bonustype = odn->dn_bonustype;
+ ndn->dn_nblkptr = odn->dn_nblkptr;
+ ndn->dn_checksum = odn->dn_checksum;
+ ndn->dn_compress = odn->dn_compress;
+ ndn->dn_nlevels = odn->dn_nlevels;
+ ndn->dn_indblkshift = odn->dn_indblkshift;
+ ndn->dn_datablkshift = odn->dn_datablkshift;
+ ndn->dn_datablkszsec = odn->dn_datablkszsec;
+ ndn->dn_datablksz = odn->dn_datablksz;
+ ndn->dn_maxblkid = odn->dn_maxblkid;
+ bcopy(&odn->dn_next_nblkptr[0], &ndn->dn_next_nblkptr[0],
+ sizeof (odn->dn_next_nblkptr));
+ bcopy(&odn->dn_next_nlevels[0], &ndn->dn_next_nlevels[0],
+ sizeof (odn->dn_next_nlevels));
+ bcopy(&odn->dn_next_indblkshift[0], &ndn->dn_next_indblkshift[0],
+ sizeof (odn->dn_next_indblkshift));
+ bcopy(&odn->dn_next_bonustype[0], &ndn->dn_next_bonustype[0],
+ sizeof (odn->dn_next_bonustype));
+ bcopy(&odn->dn_rm_spillblk[0], &ndn->dn_rm_spillblk[0],
+ sizeof (odn->dn_rm_spillblk));
+ bcopy(&odn->dn_next_bonuslen[0], &ndn->dn_next_bonuslen[0],
+ sizeof (odn->dn_next_bonuslen));
+ bcopy(&odn->dn_next_blksz[0], &ndn->dn_next_blksz[0],
+ sizeof (odn->dn_next_blksz));
+ for (i = 0; i < TXG_SIZE; i++) {
+ list_move_tail(&ndn->dn_dirty_records[i],
+ &odn->dn_dirty_records[i]);
+ }
+ bcopy(&odn->dn_ranges[0], &ndn->dn_ranges[0], sizeof (odn->dn_ranges));
+ ndn->dn_allocated_txg = odn->dn_allocated_txg;
+ ndn->dn_free_txg = odn->dn_free_txg;
+ ndn->dn_assigned_txg = odn->dn_assigned_txg;
+ ndn->dn_dirtyctx = odn->dn_dirtyctx;
+ ndn->dn_dirtyctx_firstset = odn->dn_dirtyctx_firstset;
+ ASSERT(refcount_count(&odn->dn_tx_holds) == 0);
+ refcount_transfer(&ndn->dn_holds, &odn->dn_holds);
+ ASSERT(list_is_empty(&ndn->dn_dbufs));
+ list_move_tail(&ndn->dn_dbufs, &odn->dn_dbufs);
+ ndn->dn_dbufs_count = odn->dn_dbufs_count;
+ ndn->dn_bonus = odn->dn_bonus;
+ ndn->dn_have_spill = odn->dn_have_spill;
+ ndn->dn_zio = odn->dn_zio;
+ ndn->dn_oldused = odn->dn_oldused;
+ ndn->dn_oldflags = odn->dn_oldflags;
+ ndn->dn_olduid = odn->dn_olduid;
+ ndn->dn_oldgid = odn->dn_oldgid;
+ ndn->dn_newuid = odn->dn_newuid;
+ ndn->dn_newgid = odn->dn_newgid;
+ ndn->dn_id_flags = odn->dn_id_flags;
+ dmu_zfetch_init(&ndn->dn_zfetch, NULL);
+ list_move_tail(&ndn->dn_zfetch.zf_stream, &odn->dn_zfetch.zf_stream);
+ ndn->dn_zfetch.zf_dnode = odn->dn_zfetch.zf_dnode;
+ ndn->dn_zfetch.zf_stream_cnt = odn->dn_zfetch.zf_stream_cnt;
+ ndn->dn_zfetch.zf_alloc_fail = odn->dn_zfetch.zf_alloc_fail;
+
+ /*
+ * Update back pointers. Updating the handle fixes the back pointer of
+ * every descendant dbuf as well as the bonus dbuf.
+ */
+ ASSERT(ndn->dn_handle->dnh_dnode == odn);
+ ndn->dn_handle->dnh_dnode = ndn;
+ if (ndn->dn_zfetch.zf_dnode == odn) {
+ ndn->dn_zfetch.zf_dnode = ndn;
+ }
+
+ /*
+ * Invalidate the original dnode by clearing all of its back pointers.
+ */
+ odn->dn_dbuf = NULL;
+ odn->dn_handle = NULL;
+ list_create(&odn->dn_dbufs, sizeof (dmu_buf_impl_t),
+ offsetof(dmu_buf_impl_t, db_link));
+ odn->dn_dbufs_count = 0;
+ odn->dn_bonus = NULL;
+ odn->dn_zfetch.zf_dnode = NULL;
+
+ /*
+ * Set the low bit of the objset pointer to ensure that dnode_move()
+ * recognizes the dnode as invalid in any subsequent callback.
+ */
+ POINTER_INVALIDATE(&odn->dn_objset);
+
+ /*
+ * Satisfy the destructor.
+ */
+ for (i = 0; i < TXG_SIZE; i++) {
+ list_create(&odn->dn_dirty_records[i],
+ sizeof (dbuf_dirty_record_t),
+ offsetof(dbuf_dirty_record_t, dr_dirty_node));
+ odn->dn_ranges[i].avl_root = NULL;
+ odn->dn_ranges[i].avl_numnodes = 0;
+ odn->dn_next_nlevels[i] = 0;
+ odn->dn_next_indblkshift[i] = 0;
+ odn->dn_next_bonustype[i] = 0;
+ odn->dn_rm_spillblk[i] = 0;
+ odn->dn_next_bonuslen[i] = 0;
+ odn->dn_next_blksz[i] = 0;
+ }
+ odn->dn_allocated_txg = 0;
+ odn->dn_free_txg = 0;
+ odn->dn_assigned_txg = 0;
+ odn->dn_dirtyctx = 0;
+ odn->dn_dirtyctx_firstset = NULL;
+ odn->dn_have_spill = B_FALSE;
+ odn->dn_zio = NULL;
+ odn->dn_oldused = 0;
+ odn->dn_oldflags = 0;
+ odn->dn_olduid = 0;
+ odn->dn_oldgid = 0;
+ odn->dn_newuid = 0;
+ odn->dn_newgid = 0;
+ odn->dn_id_flags = 0;
+
+ /*
+ * Mark the dnode.
+ */
+ ndn->dn_moved = 1;
+ odn->dn_moved = (uint8_t)-1;
+}
+
+#ifdef _KERNEL
+/*ARGSUSED*/
+static kmem_cbrc_t
+dnode_move(void *buf, void *newbuf, size_t size, void *arg)
+{
+ dnode_t *odn = buf, *ndn = newbuf;
+ objset_t *os;
+ int64_t refcount;
+ uint32_t dbufs;
+
+ /*
+ * The dnode is on the objset's list of known dnodes if the objset
+ * pointer is valid. We set the low bit of the objset pointer when
+ * freeing the dnode to invalidate it, and the memory patterns written
+ * by kmem (baddcafe and deadbeef) set at least one of the two low bits.
+ * A newly created dnode sets the objset pointer last of all to indicate
+ * that the dnode is known and in a valid state to be moved by this
+ * function.
+ */
+ os = odn->dn_objset;
+ if (!POINTER_IS_VALID(os)) {
+ DNODE_STAT_ADD(dnode_move_stats.dms_dnode_invalid);
+ return (KMEM_CBRC_DONT_KNOW);
+ }
+
+ /*
+ * Ensure that the objset does not go away during the move.
+ */
+ rw_enter(&os_lock, RW_WRITER);
+ if (os != odn->dn_objset) {
+ rw_exit(&os_lock);
+ DNODE_STAT_ADD(dnode_move_stats.dms_dnode_recheck1);
+ return (KMEM_CBRC_DONT_KNOW);
+ }
+
+ /*
+ * If the dnode is still valid, then so is the objset. We know that no
+ * valid objset can be freed while we hold os_lock, so we can safely
+ * ensure that the objset remains in use.
+ */
+ mutex_enter(&os->os_lock);
+
+ /*
+ * Recheck the objset pointer in case the dnode was removed just before
+ * acquiring the lock.
+ */
+ if (os != odn->dn_objset) {
+ mutex_exit(&os->os_lock);
+ rw_exit(&os_lock);
+ DNODE_STAT_ADD(dnode_move_stats.dms_dnode_recheck2);
+ return (KMEM_CBRC_DONT_KNOW);
+ }
+
+ /*
+ * At this point we know that as long as we hold os->os_lock, the dnode
+ * cannot be freed and fields within the dnode can be safely accessed.
+ * The objset listing this dnode cannot go away as long as this dnode is
+ * on its list.
+ */
+ rw_exit(&os_lock);
+ if (DMU_OBJECT_IS_SPECIAL(odn->dn_object)) {
+ mutex_exit(&os->os_lock);
+ DNODE_STAT_ADD(dnode_move_stats.dms_dnode_special);
+ return (KMEM_CBRC_NO);
+ }
+ ASSERT(odn->dn_dbuf != NULL); /* only "special" dnodes have no parent */
+
+ /*
+ * Lock the dnode handle to prevent the dnode from obtaining any new
+ * holds. This also prevents the descendant dbufs and the bonus dbuf
+ * from accessing the dnode, so that we can discount their holds. The
+ * handle is safe to access because we know that while the dnode cannot
+ * go away, neither can its handle. Once we hold dnh_zrlock, we can
+ * safely move any dnode referenced only by dbufs.
+ */
+ if (!zrl_tryenter(&odn->dn_handle->dnh_zrlock)) {
+ mutex_exit(&os->os_lock);
+ DNODE_STAT_ADD(dnode_move_stats.dms_dnode_handle);
+ return (KMEM_CBRC_LATER);
+ }
+
+ /*
+ * Ensure a consistent view of the dnode's holds and the dnode's dbufs.
+ * We need to guarantee that there is a hold for every dbuf in order to
+ * determine whether the dnode is actively referenced. Falsely matching
+ * a dbuf to an active hold would lead to an unsafe move. It's possible
+ * that a thread already having an active dnode hold is about to add a
+ * dbuf, and we can't compare hold and dbuf counts while the add is in
+ * progress.
+ */
+ if (!rw_tryenter(&odn->dn_struct_rwlock, RW_WRITER)) {
+ zrl_exit(&odn->dn_handle->dnh_zrlock);
+ mutex_exit(&os->os_lock);
+ DNODE_STAT_ADD(dnode_move_stats.dms_dnode_rwlock);
+ return (KMEM_CBRC_LATER);
+ }
+
+ /*
+ * A dbuf may be removed (evicted) without an active dnode hold. In that
+ * case, the dbuf count is decremented under the handle lock before the
+ * dbuf's hold is released. This order ensures that if we count the hold
+ * after the dbuf is removed but before its hold is released, we will
+ * treat the unmatched hold as active and exit safely. If we count the
+ * hold before the dbuf is removed, the hold is discounted, and the
+ * removal is blocked until the move completes.
+ */
+ refcount = refcount_count(&odn->dn_holds);
+ ASSERT(refcount >= 0);
+ dbufs = odn->dn_dbufs_count;
+
+ /* We can't have more dbufs than dnode holds. */
+ ASSERT3U(dbufs, <=, refcount);
+ DTRACE_PROBE3(dnode__move, dnode_t *, odn, int64_t, refcount,
+ uint32_t, dbufs);
+
+ if (refcount > dbufs) {
+ rw_exit(&odn->dn_struct_rwlock);
+ zrl_exit(&odn->dn_handle->dnh_zrlock);
+ mutex_exit(&os->os_lock);
+ DNODE_STAT_ADD(dnode_move_stats.dms_dnode_active);
+ return (KMEM_CBRC_LATER);
+ }
+
+ rw_exit(&odn->dn_struct_rwlock);
+
+ /*
+ * At this point we know that anyone with a hold on the dnode is not
+ * actively referencing it. The dnode is known and in a valid state to
+ * move. We're holding the locks needed to execute the critical section.
+ */
+ dnode_move_impl(odn, ndn);
+
+ list_link_replace(&odn->dn_link, &ndn->dn_link);
+ /* If the dnode was safe to move, the refcount cannot have changed. */
+ ASSERT(refcount == refcount_count(&ndn->dn_holds));
+ ASSERT(dbufs == ndn->dn_dbufs_count);
+ zrl_exit(&ndn->dn_handle->dnh_zrlock); /* handle has moved */
+ mutex_exit(&os->os_lock);
+
+ return (KMEM_CBRC_YES);
+}
+#endif /* _KERNEL */
+
+void
+dnode_special_close(dnode_handle_t *dnh)
+{
+ dnode_t *dn = dnh->dnh_dnode;
+
+ /*
+ * Wait for final references to the dnode to clear. This can
+ * only happen if the arc is asyncronously evicting state that
+ * has a hold on this dnode while we are trying to evict this
+ * dnode.
+ */
+ while (refcount_count(&dn->dn_holds) > 0)
+ delay(1);
+ zrl_add(&dnh->dnh_zrlock);
+ dnode_destroy(dn); /* implicit zrl_remove() */
+ zrl_destroy(&dnh->dnh_zrlock);
+ dnh->dnh_dnode = NULL;
+}
+
+dnode_t *
+dnode_special_open(objset_t *os, dnode_phys_t *dnp, uint64_t object,
+ dnode_handle_t *dnh)
+{
+ dnode_t *dn = dnode_create(os, dnp, NULL, object, dnh);
+ dnh->dnh_dnode = dn;
+ zrl_init(&dnh->dnh_zrlock);
+ DNODE_VERIFY(dn);
+ return (dn);
+}
+
+static void
+dnode_buf_pageout(dmu_buf_t *db, void *arg)
+{
+ dnode_children_t *children_dnodes = arg;
+ int i;
+ int epb = db->db_size >> DNODE_SHIFT;
+
+ ASSERT(epb == children_dnodes->dnc_count);
+
+ for (i = 0; i < epb; i++) {
+ dnode_handle_t *dnh = &children_dnodes->dnc_children[i];
+ dnode_t *dn;
+
+ /*
+ * The dnode handle lock guards against the dnode moving to
+ * another valid address, so there is no need here to guard
+ * against changes to or from NULL.
+ */
+ if (dnh->dnh_dnode == NULL) {
+ zrl_destroy(&dnh->dnh_zrlock);
+ continue;
+ }
+
+ zrl_add(&dnh->dnh_zrlock);
+ dn = dnh->dnh_dnode;
+ /*
+ * If there are holds on this dnode, then there should
+ * be holds on the dnode's containing dbuf as well; thus
+ * it wouldn't be eligible for eviction and this function
+ * would not have been called.
+ */
+ ASSERT(refcount_is_zero(&dn->dn_holds));
+ ASSERT(refcount_is_zero(&dn->dn_tx_holds));
+
+ dnode_destroy(dn); /* implicit zrl_remove() */
+ zrl_destroy(&dnh->dnh_zrlock);
+ dnh->dnh_dnode = NULL;
+ }
+ kmem_free(children_dnodes, sizeof (dnode_children_t) +
+ (epb - 1) * sizeof (dnode_handle_t));
+}
+
+/*
+ * errors:
+ * EINVAL - invalid object number.
+ * EIO - i/o error.
+ * succeeds even for free dnodes.
+ */
+int
+dnode_hold_impl(objset_t *os, uint64_t object, int flag,
+ void *tag, dnode_t **dnp)
+{
+ int epb, idx, err;
+ int drop_struct_lock = FALSE;
+ int type;
+ uint64_t blk;
+ dnode_t *mdn, *dn;
+ dmu_buf_impl_t *db;
+ dnode_children_t *children_dnodes;
+ dnode_handle_t *dnh;
+
+ /*
+ * If you are holding the spa config lock as writer, you shouldn't
+ * be asking the DMU to do *anything* unless it's the root pool
+ * which may require us to read from the root filesystem while
+ * holding some (not all) of the locks as writer.
+ */
+ ASSERT(spa_config_held(os->os_spa, SCL_ALL, RW_WRITER) == 0 ||
+ (spa_is_root(os->os_spa) &&
+ spa_config_held(os->os_spa, SCL_STATE, RW_WRITER)));
+
+ if (object == DMU_USERUSED_OBJECT || object == DMU_GROUPUSED_OBJECT) {
+ dn = (object == DMU_USERUSED_OBJECT) ?
+ DMU_USERUSED_DNODE(os) : DMU_GROUPUSED_DNODE(os);
+ if (dn == NULL)
+ return (ENOENT);
+ type = dn->dn_type;
+ if ((flag & DNODE_MUST_BE_ALLOCATED) && type == DMU_OT_NONE)
+ return (ENOENT);
+ if ((flag & DNODE_MUST_BE_FREE) && type != DMU_OT_NONE)
+ return (EEXIST);
+ DNODE_VERIFY(dn);
+ (void) refcount_add(&dn->dn_holds, tag);
+ *dnp = dn;
+ return (0);
+ }
+
+ if (object == 0 || object >= DN_MAX_OBJECT)
+ return (EINVAL);
+
+ mdn = DMU_META_DNODE(os);
+ ASSERT(mdn->dn_object == DMU_META_DNODE_OBJECT);
+
+ DNODE_VERIFY(mdn);
+
+ if (!RW_WRITE_HELD(&mdn->dn_struct_rwlock)) {
+ rw_enter(&mdn->dn_struct_rwlock, RW_READER);
+ drop_struct_lock = TRUE;
+ }
+
+ blk = dbuf_whichblock(mdn, object * sizeof (dnode_phys_t));
+
+ db = dbuf_hold(mdn, blk, FTAG);
+ if (drop_struct_lock)
+ rw_exit(&mdn->dn_struct_rwlock);
+ if (db == NULL)
+ return (EIO);
+ err = dbuf_read(db, NULL, DB_RF_CANFAIL);
+ if (err) {
+ dbuf_rele(db, FTAG);
+ return (err);
+ }
+
+ ASSERT3U(db->db.db_size, >=, 1<<DNODE_SHIFT);
+ epb = db->db.db_size >> DNODE_SHIFT;
+
+ idx = object & (epb-1);
+
+ ASSERT(DB_DNODE(db)->dn_type == DMU_OT_DNODE);
+ children_dnodes = dmu_buf_get_user(&db->db);
+ if (children_dnodes == NULL) {
+ int i;
+ dnode_children_t *winner;
+ children_dnodes = kmem_alloc(sizeof (dnode_children_t) +
+ (epb - 1) * sizeof (dnode_handle_t), KM_SLEEP);
+ children_dnodes->dnc_count = epb;
+ dnh = &children_dnodes->dnc_children[0];
+ for (i = 0; i < epb; i++) {
+ zrl_init(&dnh[i].dnh_zrlock);
+ dnh[i].dnh_dnode = NULL;
+ }
+ if (winner = dmu_buf_set_user(&db->db, children_dnodes, NULL,
+ dnode_buf_pageout)) {
+ kmem_free(children_dnodes, sizeof (dnode_children_t) +
+ (epb - 1) * sizeof (dnode_handle_t));
+ children_dnodes = winner;
+ }
+ }
+ ASSERT(children_dnodes->dnc_count == epb);
+
+ dnh = &children_dnodes->dnc_children[idx];
+ zrl_add(&dnh->dnh_zrlock);
+ if ((dn = dnh->dnh_dnode) == NULL) {
+ dnode_phys_t *phys = (dnode_phys_t *)db->db.db_data+idx;
+ dnode_t *winner;
+
+ dn = dnode_create(os, phys, db, object, dnh);
+ winner = atomic_cas_ptr(&dnh->dnh_dnode, NULL, dn);
+ if (winner != NULL) {
+ zrl_add(&dnh->dnh_zrlock);
+ dnode_destroy(dn); /* implicit zrl_remove() */
+ dn = winner;
+ }
+ }
+
+ mutex_enter(&dn->dn_mtx);
+ type = dn->dn_type;
+ if (dn->dn_free_txg ||
+ ((flag & DNODE_MUST_BE_ALLOCATED) && type == DMU_OT_NONE) ||
+ ((flag & DNODE_MUST_BE_FREE) &&
+ (type != DMU_OT_NONE || !refcount_is_zero(&dn->dn_holds)))) {
+ mutex_exit(&dn->dn_mtx);
+ zrl_remove(&dnh->dnh_zrlock);
+ dbuf_rele(db, FTAG);
+ return (type == DMU_OT_NONE ? ENOENT : EEXIST);
+ }
+ mutex_exit(&dn->dn_mtx);
+
+ if (refcount_add(&dn->dn_holds, tag) == 1)
+ dbuf_add_ref(db, dnh);
+ /* Now we can rely on the hold to prevent the dnode from moving. */
+ zrl_remove(&dnh->dnh_zrlock);
+
+ DNODE_VERIFY(dn);
+ ASSERT3P(dn->dn_dbuf, ==, db);
+ ASSERT3U(dn->dn_object, ==, object);
+ dbuf_rele(db, FTAG);
+
+ *dnp = dn;
+ return (0);
+}
+
+/*
+ * Return held dnode if the object is allocated, NULL if not.
+ */
+int
+dnode_hold(objset_t *os, uint64_t object, void *tag, dnode_t **dnp)
+{
+ return (dnode_hold_impl(os, object, DNODE_MUST_BE_ALLOCATED, tag, dnp));
+}
+
+/*
+ * Can only add a reference if there is already at least one
+ * reference on the dnode. Returns FALSE if unable to add a
+ * new reference.
+ */
+boolean_t
+dnode_add_ref(dnode_t *dn, void *tag)
+{
+ mutex_enter(&dn->dn_mtx);
+ if (refcount_is_zero(&dn->dn_holds)) {
+ mutex_exit(&dn->dn_mtx);
+ return (FALSE);
+ }
+ VERIFY(1 < refcount_add(&dn->dn_holds, tag));
+ mutex_exit(&dn->dn_mtx);
+ return (TRUE);
+}
+
+void
+dnode_rele(dnode_t *dn, void *tag)
+{
+ uint64_t refs;
+ /* Get while the hold prevents the dnode from moving. */
+ dmu_buf_impl_t *db = dn->dn_dbuf;
+ dnode_handle_t *dnh = dn->dn_handle;
+
+ mutex_enter(&dn->dn_mtx);
+ refs = refcount_remove(&dn->dn_holds, tag);
+ mutex_exit(&dn->dn_mtx);
+
+ /*
+ * It's unsafe to release the last hold on a dnode by dnode_rele() or
+ * indirectly by dbuf_rele() while relying on the dnode handle to
+ * prevent the dnode from moving, since releasing the last hold could
+ * result in the dnode's parent dbuf evicting its dnode handles. For
+ * that reason anyone calling dnode_rele() or dbuf_rele() without some
+ * other direct or indirect hold on the dnode must first drop the dnode
+ * handle.
+ */
+ ASSERT(refs > 0 || dnh->dnh_zrlock.zr_owner != curthread);
+
+ /* NOTE: the DNODE_DNODE does not have a dn_dbuf */
+ if (refs == 0 && db != NULL) {
+ /*
+ * Another thread could add a hold to the dnode handle in
+ * dnode_hold_impl() while holding the parent dbuf. Since the
+ * hold on the parent dbuf prevents the handle from being
+ * destroyed, the hold on the handle is OK. We can't yet assert
+ * that the handle has zero references, but that will be
+ * asserted anyway when the handle gets destroyed.
+ */
+ dbuf_rele(db, dnh);
+ }
+}
+
+void
+dnode_setdirty(dnode_t *dn, dmu_tx_t *tx)
+{
+ objset_t *os = dn->dn_objset;
+ uint64_t txg = tx->tx_txg;
+
+ if (DMU_OBJECT_IS_SPECIAL(dn->dn_object)) {
+ dsl_dataset_dirty(os->os_dsl_dataset, tx);
+ return;
+ }
+
+ DNODE_VERIFY(dn);
+
+#ifdef ZFS_DEBUG
+ mutex_enter(&dn->dn_mtx);
+ ASSERT(dn->dn_phys->dn_type || dn->dn_allocated_txg);
+ ASSERT(dn->dn_free_txg == 0 || dn->dn_free_txg >= txg);
+ mutex_exit(&dn->dn_mtx);
+#endif
+
+ /*
+ * Determine old uid/gid when necessary
+ */
+ dmu_objset_userquota_get_ids(dn, B_TRUE, tx);
+
+ mutex_enter(&os->os_lock);
+
+ /*
+ * If we are already marked dirty, we're done.
+ */
+ if (list_link_active(&dn->dn_dirty_link[txg & TXG_MASK])) {
+ mutex_exit(&os->os_lock);
+ return;
+ }
+
+ ASSERT(!refcount_is_zero(&dn->dn_holds) || list_head(&dn->dn_dbufs));
+ ASSERT(dn->dn_datablksz != 0);
+ ASSERT3U(dn->dn_next_bonuslen[txg&TXG_MASK], ==, 0);
+ ASSERT3U(dn->dn_next_blksz[txg&TXG_MASK], ==, 0);
+ ASSERT3U(dn->dn_next_bonustype[txg&TXG_MASK], ==, 0);
+
+ dprintf_ds(os->os_dsl_dataset, "obj=%llu txg=%llu\n",
+ dn->dn_object, txg);
+
+ if (dn->dn_free_txg > 0 && dn->dn_free_txg <= txg) {
+ list_insert_tail(&os->os_free_dnodes[txg&TXG_MASK], dn);
+ } else {
+ list_insert_tail(&os->os_dirty_dnodes[txg&TXG_MASK], dn);
+ }
+
+ mutex_exit(&os->os_lock);
+
+ /*
+ * The dnode maintains a hold on its containing dbuf as
+ * long as there are holds on it. Each instantiated child
+ * dbuf maintains a hold on the dnode. When the last child
+ * drops its hold, the dnode will drop its hold on the
+ * containing dbuf. We add a "dirty hold" here so that the
+ * dnode will hang around after we finish processing its
+ * children.
+ */
+ VERIFY(dnode_add_ref(dn, (void *)(uintptr_t)tx->tx_txg));
+
+ (void) dbuf_dirty(dn->dn_dbuf, tx);
+
+ dsl_dataset_dirty(os->os_dsl_dataset, tx);
+}
+
+void
+dnode_free(dnode_t *dn, dmu_tx_t *tx)
+{
+ int txgoff = tx->tx_txg & TXG_MASK;
+
+ dprintf("dn=%p txg=%llu\n", dn, tx->tx_txg);
+
+ /* we should be the only holder... hopefully */
+ /* ASSERT3U(refcount_count(&dn->dn_holds), ==, 1); */
+
+ mutex_enter(&dn->dn_mtx);
+ if (dn->dn_type == DMU_OT_NONE || dn->dn_free_txg) {
+ mutex_exit(&dn->dn_mtx);
+ return;
+ }
+ dn->dn_free_txg = tx->tx_txg;
+ mutex_exit(&dn->dn_mtx);
+
+ /*
+ * If the dnode is already dirty, it needs to be moved from
+ * the dirty list to the free list.
+ */
+ mutex_enter(&dn->dn_objset->os_lock);
+ if (list_link_active(&dn->dn_dirty_link[txgoff])) {
+ list_remove(&dn->dn_objset->os_dirty_dnodes[txgoff], dn);
+ list_insert_tail(&dn->dn_objset->os_free_dnodes[txgoff], dn);
+ mutex_exit(&dn->dn_objset->os_lock);
+ } else {
+ mutex_exit(&dn->dn_objset->os_lock);
+ dnode_setdirty(dn, tx);
+ }
+}
+
+/*
+ * Try to change the block size for the indicated dnode. This can only
+ * succeed if there are no blocks allocated or dirty beyond first block
+ */
+int
+dnode_set_blksz(dnode_t *dn, uint64_t size, int ibs, dmu_tx_t *tx)
+{
+ dmu_buf_impl_t *db, *db_next;
+ int err;
+
+ if (size == 0)
+ size = SPA_MINBLOCKSIZE;
+ if (size > SPA_MAXBLOCKSIZE)
+ size = SPA_MAXBLOCKSIZE;
+ else
+ size = P2ROUNDUP(size, SPA_MINBLOCKSIZE);
+
+ if (ibs == dn->dn_indblkshift)
+ ibs = 0;
+
+ if (size >> SPA_MINBLOCKSHIFT == dn->dn_datablkszsec && ibs == 0)
+ return (0);
+
+ rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
+
+ /* Check for any allocated blocks beyond the first */
+ if (dn->dn_phys->dn_maxblkid != 0)
+ goto fail;
+
+ mutex_enter(&dn->dn_dbufs_mtx);
+ for (db = list_head(&dn->dn_dbufs); db; db = db_next) {
+ db_next = list_next(&dn->dn_dbufs, db);
+
+ if (db->db_blkid != 0 && db->db_blkid != DMU_BONUS_BLKID &&
+ db->db_blkid != DMU_SPILL_BLKID) {
+ mutex_exit(&dn->dn_dbufs_mtx);
+ goto fail;
+ }
+ }
+ mutex_exit(&dn->dn_dbufs_mtx);
+
+ if (ibs && dn->dn_nlevels != 1)
+ goto fail;
+
+ /* resize the old block */
+ err = dbuf_hold_impl(dn, 0, 0, TRUE, FTAG, &db);
+ if (err == 0)
+ dbuf_new_size(db, size, tx);
+ else if (err != ENOENT)
+ goto fail;
+
+ dnode_setdblksz(dn, size);
+ dnode_setdirty(dn, tx);
+ dn->dn_next_blksz[tx->tx_txg&TXG_MASK] = size;
+ if (ibs) {
+ dn->dn_indblkshift = ibs;
+ dn->dn_next_indblkshift[tx->tx_txg&TXG_MASK] = ibs;
+ }
+ /* rele after we have fixed the blocksize in the dnode */
+ if (db)
+ dbuf_rele(db, FTAG);
+
+ rw_exit(&dn->dn_struct_rwlock);
+ return (0);
+
+fail:
+ rw_exit(&dn->dn_struct_rwlock);
+ return (ENOTSUP);
+}
+
+/* read-holding callers must not rely on the lock being continuously held */
+void
+dnode_new_blkid(dnode_t *dn, uint64_t blkid, dmu_tx_t *tx, boolean_t have_read)
+{
+ uint64_t txgoff = tx->tx_txg & TXG_MASK;
+ int epbs, new_nlevels;
+ uint64_t sz;
+
+ ASSERT(blkid != DMU_BONUS_BLKID);
+
+ ASSERT(have_read ?
+ RW_READ_HELD(&dn->dn_struct_rwlock) :
+ RW_WRITE_HELD(&dn->dn_struct_rwlock));
+
+ /*
+ * if we have a read-lock, check to see if we need to do any work
+ * before upgrading to a write-lock.
+ */
+ if (have_read) {
+ if (blkid <= dn->dn_maxblkid)
+ return;
+
+ if (!rw_tryupgrade(&dn->dn_struct_rwlock)) {
+ rw_exit(&dn->dn_struct_rwlock);
+ rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
+ }
+ }
+
+ if (blkid <= dn->dn_maxblkid)
+ goto out;
+
+ dn->dn_maxblkid = blkid;
+
+ /*
+ * Compute the number of levels necessary to support the new maxblkid.
+ */
+ new_nlevels = 1;
+ epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT;
+ for (sz = dn->dn_nblkptr;
+ sz <= blkid && sz >= dn->dn_nblkptr; sz <<= epbs)
+ new_nlevels++;
+
+ if (new_nlevels > dn->dn_nlevels) {
+ int old_nlevels = dn->dn_nlevels;
+ dmu_buf_impl_t *db;
+ list_t *list;
+ dbuf_dirty_record_t *new, *dr, *dr_next;
+
+ dn->dn_nlevels = new_nlevels;
+
+ ASSERT3U(new_nlevels, >, dn->dn_next_nlevels[txgoff]);
+ dn->dn_next_nlevels[txgoff] = new_nlevels;
+
+ /* dirty the left indirects */
+ db = dbuf_hold_level(dn, old_nlevels, 0, FTAG);
+ ASSERT(db != NULL);
+ new = dbuf_dirty(db, tx);
+ dbuf_rele(db, FTAG);
+
+ /* transfer the dirty records to the new indirect */
+ mutex_enter(&dn->dn_mtx);
+ mutex_enter(&new->dt.di.dr_mtx);
+ list = &dn->dn_dirty_records[txgoff];
+ for (dr = list_head(list); dr; dr = dr_next) {
+ dr_next = list_next(&dn->dn_dirty_records[txgoff], dr);
+ if (dr->dr_dbuf->db_level != new_nlevels-1 &&
+ dr->dr_dbuf->db_blkid != DMU_BONUS_BLKID &&
+ dr->dr_dbuf->db_blkid != DMU_SPILL_BLKID) {
+ ASSERT(dr->dr_dbuf->db_level == old_nlevels-1);
+ list_remove(&dn->dn_dirty_records[txgoff], dr);
+ list_insert_tail(&new->dt.di.dr_children, dr);
+ dr->dr_parent = new;
+ }
+ }
+ mutex_exit(&new->dt.di.dr_mtx);
+ mutex_exit(&dn->dn_mtx);
+ }
+
+out:
+ if (have_read)
+ rw_downgrade(&dn->dn_struct_rwlock);
+}
+
+void
+dnode_clear_range(dnode_t *dn, uint64_t blkid, uint64_t nblks, dmu_tx_t *tx)
+{
+ avl_tree_t *tree = &dn->dn_ranges[tx->tx_txg&TXG_MASK];
+ avl_index_t where;
+ free_range_t *rp;
+ free_range_t rp_tofind;
+ uint64_t endblk = blkid + nblks;
+
+ ASSERT(MUTEX_HELD(&dn->dn_mtx));
+ ASSERT(nblks <= UINT64_MAX - blkid); /* no overflow */
+
+ dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n",
+ blkid, nblks, tx->tx_txg);
+ rp_tofind.fr_blkid = blkid;
+ rp = avl_find(tree, &rp_tofind, &where);
+ if (rp == NULL)
+ rp = avl_nearest(tree, where, AVL_BEFORE);
+ if (rp == NULL)
+ rp = avl_nearest(tree, where, AVL_AFTER);
+
+ while (rp && (rp->fr_blkid <= blkid + nblks)) {
+ uint64_t fr_endblk = rp->fr_blkid + rp->fr_nblks;
+ free_range_t *nrp = AVL_NEXT(tree, rp);
+
+ if (blkid <= rp->fr_blkid && endblk >= fr_endblk) {
+ /* clear this entire range */
+ avl_remove(tree, rp);
+ kmem_free(rp, sizeof (free_range_t));
+ } else if (blkid <= rp->fr_blkid &&
+ endblk > rp->fr_blkid && endblk < fr_endblk) {
+ /* clear the beginning of this range */
+ rp->fr_blkid = endblk;
+ rp->fr_nblks = fr_endblk - endblk;
+ } else if (blkid > rp->fr_blkid && blkid < fr_endblk &&
+ endblk >= fr_endblk) {
+ /* clear the end of this range */
+ rp->fr_nblks = blkid - rp->fr_blkid;
+ } else if (blkid > rp->fr_blkid && endblk < fr_endblk) {
+ /* clear a chunk out of this range */
+ free_range_t *new_rp =
+ kmem_alloc(sizeof (free_range_t), KM_SLEEP);
+
+ new_rp->fr_blkid = endblk;
+ new_rp->fr_nblks = fr_endblk - endblk;
+ avl_insert_here(tree, new_rp, rp, AVL_AFTER);
+ rp->fr_nblks = blkid - rp->fr_blkid;
+ }
+ /* there may be no overlap */
+ rp = nrp;
+ }
+}
+
+void
+dnode_free_range(dnode_t *dn, uint64_t off, uint64_t len, dmu_tx_t *tx)
+{
+ dmu_buf_impl_t *db;
+ uint64_t blkoff, blkid, nblks;
+ int blksz, blkshift, head, tail;
+ int trunc = FALSE;
+ int epbs;
+
+ rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
+ blksz = dn->dn_datablksz;
+ blkshift = dn->dn_datablkshift;
+ epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT;
+
+ if (len == -1ULL) {
+ len = UINT64_MAX - off;
+ trunc = TRUE;
+ }
+
+ /*
+ * First, block align the region to free:
+ */
+ if (ISP2(blksz)) {
+ head = P2NPHASE(off, blksz);
+ blkoff = P2PHASE(off, blksz);
+ if ((off >> blkshift) > dn->dn_maxblkid)
+ goto out;
+ } else {
+ ASSERT(dn->dn_maxblkid == 0);
+ if (off == 0 && len >= blksz) {
+ /* Freeing the whole block; fast-track this request */
+ blkid = 0;
+ nblks = 1;
+ goto done;
+ } else if (off >= blksz) {
+ /* Freeing past end-of-data */
+ goto out;
+ } else {
+ /* Freeing part of the block. */
+ head = blksz - off;
+ ASSERT3U(head, >, 0);
+ }
+ blkoff = off;
+ }
+ /* zero out any partial block data at the start of the range */
+ if (head) {
+ ASSERT3U(blkoff + head, ==, blksz);
+ if (len < head)
+ head = len;
+ if (dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, off), TRUE,
+ FTAG, &db) == 0) {
+ caddr_t data;
+
+ /* don't dirty if it isn't on disk and isn't dirty */
+ if (db->db_last_dirty ||
+ (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr))) {
+ rw_exit(&dn->dn_struct_rwlock);
+ dbuf_will_dirty(db, tx);
+ rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
+ data = db->db.db_data;
+ bzero(data + blkoff, head);
+ }
+ dbuf_rele(db, FTAG);
+ }
+ off += head;
+ len -= head;
+ }
+
+ /* If the range was less than one block, we're done */
+ if (len == 0)
+ goto out;
+
+ /* If the remaining range is past end of file, we're done */
+ if ((off >> blkshift) > dn->dn_maxblkid)
+ goto out;
+
+ ASSERT(ISP2(blksz));
+ if (trunc)
+ tail = 0;
+ else
+ tail = P2PHASE(len, blksz);
+
+ ASSERT3U(P2PHASE(off, blksz), ==, 0);
+ /* zero out any partial block data at the end of the range */
+ if (tail) {
+ if (len < tail)
+ tail = len;
+ if (dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, off+len),
+ TRUE, FTAG, &db) == 0) {
+ /* don't dirty if not on disk and not dirty */
+ if (db->db_last_dirty ||
+ (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr))) {
+ rw_exit(&dn->dn_struct_rwlock);
+ dbuf_will_dirty(db, tx);
+ rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
+ bzero(db->db.db_data, tail);
+ }
+ dbuf_rele(db, FTAG);
+ }
+ len -= tail;
+ }
+
+ /* If the range did not include a full block, we are done */
+ if (len == 0)
+ goto out;
+
+ ASSERT(IS_P2ALIGNED(off, blksz));
+ ASSERT(trunc || IS_P2ALIGNED(len, blksz));
+ blkid = off >> blkshift;
+ nblks = len >> blkshift;
+ if (trunc)
+ nblks += 1;
+
+ /*
+ * Read in and mark all the level-1 indirects dirty,
+ * so that they will stay in memory until syncing phase.
+ * Always dirty the first and last indirect to make sure
+ * we dirty all the partial indirects.
+ */
+ if (dn->dn_nlevels > 1) {
+ uint64_t i, first, last;
+ int shift = epbs + dn->dn_datablkshift;
+
+ first = blkid >> epbs;
+ if (db = dbuf_hold_level(dn, 1, first, FTAG)) {
+ dbuf_will_dirty(db, tx);
+ dbuf_rele(db, FTAG);
+ }
+ if (trunc)
+ last = dn->dn_maxblkid >> epbs;
+ else
+ last = (blkid + nblks - 1) >> epbs;
+ if (last > first && (db = dbuf_hold_level(dn, 1, last, FTAG))) {
+ dbuf_will_dirty(db, tx);
+ dbuf_rele(db, FTAG);
+ }
+ for (i = first + 1; i < last; i++) {
+ uint64_t ibyte = i << shift;
+ int err;
+
+ err = dnode_next_offset(dn,
+ DNODE_FIND_HAVELOCK, &ibyte, 1, 1, 0);
+ i = ibyte >> shift;
+ if (err == ESRCH || i >= last)
+ break;
+ ASSERT(err == 0);
+ db = dbuf_hold_level(dn, 1, i, FTAG);
+ if (db) {
+ dbuf_will_dirty(db, tx);
+ dbuf_rele(db, FTAG);
+ }
+ }
+ }
+done:
+ /*
+ * Add this range to the dnode range list.
+ * We will finish up this free operation in the syncing phase.
+ */
+ mutex_enter(&dn->dn_mtx);
+ dnode_clear_range(dn, blkid, nblks, tx);
+ {
+ free_range_t *rp, *found;
+ avl_index_t where;
+ avl_tree_t *tree = &dn->dn_ranges[tx->tx_txg&TXG_MASK];
+
+ /* Add new range to dn_ranges */
+ rp = kmem_alloc(sizeof (free_range_t), KM_SLEEP);
+ rp->fr_blkid = blkid;
+ rp->fr_nblks = nblks;
+ found = avl_find(tree, rp, &where);
+ ASSERT(found == NULL);
+ avl_insert(tree, rp, where);
+ dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n",
+ blkid, nblks, tx->tx_txg);
+ }
+ mutex_exit(&dn->dn_mtx);
+
+ dbuf_free_range(dn, blkid, blkid + nblks - 1, tx);
+ dnode_setdirty(dn, tx);
+out:
+ if (trunc && dn->dn_maxblkid >= (off >> blkshift))
+ dn->dn_maxblkid = (off >> blkshift ? (off >> blkshift) - 1 : 0);
+
+ rw_exit(&dn->dn_struct_rwlock);
+}
+
+static boolean_t
+dnode_spill_freed(dnode_t *dn)
+{
+ int i;
+
+ mutex_enter(&dn->dn_mtx);
+ for (i = 0; i < TXG_SIZE; i++) {
+ if (dn->dn_rm_spillblk[i] == DN_KILL_SPILLBLK)
+ break;
+ }
+ mutex_exit(&dn->dn_mtx);
+ return (i < TXG_SIZE);
+}
+
+/* return TRUE if this blkid was freed in a recent txg, or FALSE if it wasn't */
+uint64_t
+dnode_block_freed(dnode_t *dn, uint64_t blkid)
+{
+ free_range_t range_tofind;
+ void *dp = spa_get_dsl(dn->dn_objset->os_spa);
+ int i;
+
+ if (blkid == DMU_BONUS_BLKID)
+ return (FALSE);
+
+ /*
+ * If we're in the process of opening the pool, dp will not be
+ * set yet, but there shouldn't be anything dirty.
+ */
+ if (dp == NULL)
+ return (FALSE);
+
+ if (dn->dn_free_txg)
+ return (TRUE);
+
+ if (blkid == DMU_SPILL_BLKID)
+ return (dnode_spill_freed(dn));
+
+ range_tofind.fr_blkid = blkid;
+ mutex_enter(&dn->dn_mtx);
+ for (i = 0; i < TXG_SIZE; i++) {
+ free_range_t *range_found;
+ avl_index_t idx;
+
+ range_found = avl_find(&dn->dn_ranges[i], &range_tofind, &idx);
+ if (range_found) {
+ ASSERT(range_found->fr_nblks > 0);
+ break;
+ }
+ range_found = avl_nearest(&dn->dn_ranges[i], idx, AVL_BEFORE);
+ if (range_found &&
+ range_found->fr_blkid + range_found->fr_nblks > blkid)
+ break;
+ }
+ mutex_exit(&dn->dn_mtx);
+ return (i < TXG_SIZE);
+}
+
+/* call from syncing context when we actually write/free space for this dnode */
+void
+dnode_diduse_space(dnode_t *dn, int64_t delta)
+{
+ uint64_t space;
+ dprintf_dnode(dn, "dn=%p dnp=%p used=%llu delta=%lld\n",
+ dn, dn->dn_phys,
+ (u_longlong_t)dn->dn_phys->dn_used,
+ (longlong_t)delta);
+
+ mutex_enter(&dn->dn_mtx);
+ space = DN_USED_BYTES(dn->dn_phys);
+ if (delta > 0) {
+ ASSERT3U(space + delta, >=, space); /* no overflow */
+ } else {
+ ASSERT3U(space, >=, -delta); /* no underflow */
+ }
+ space += delta;
+ if (spa_version(dn->dn_objset->os_spa) < SPA_VERSION_DNODE_BYTES) {
+ ASSERT((dn->dn_phys->dn_flags & DNODE_FLAG_USED_BYTES) == 0);
+ ASSERT3U(P2PHASE(space, 1<<DEV_BSHIFT), ==, 0);
+ dn->dn_phys->dn_used = space >> DEV_BSHIFT;
+ } else {
+ dn->dn_phys->dn_used = space;
+ dn->dn_phys->dn_flags |= DNODE_FLAG_USED_BYTES;
+ }
+ mutex_exit(&dn->dn_mtx);
+}
+
+/*
+ * Call when we think we're going to write/free space in open context.
+ * Be conservative (ie. OK to write less than this or free more than
+ * this, but don't write more or free less).
+ */
+void
+dnode_willuse_space(dnode_t *dn, int64_t space, dmu_tx_t *tx)
+{
+ objset_t *os = dn->dn_objset;
+ dsl_dataset_t *ds = os->os_dsl_dataset;
+
+ if (space > 0)
+ space = spa_get_asize(os->os_spa, space);
+
+ if (ds)
+ dsl_dir_willuse_space(ds->ds_dir, space, tx);
+
+ dmu_tx_willuse_space(tx, space);
+}
+
+/*
+ * This function scans a block at the indicated "level" looking for
+ * a hole or data (depending on 'flags'). If level > 0, then we are
+ * scanning an indirect block looking at its pointers. If level == 0,
+ * then we are looking at a block of dnodes. If we don't find what we
+ * are looking for in the block, we return ESRCH. Otherwise, return
+ * with *offset pointing to the beginning (if searching forwards) or
+ * end (if searching backwards) of the range covered by the block
+ * pointer we matched on (or dnode).
+ *
+ * The basic search algorithm used below by dnode_next_offset() is to
+ * use this function to search up the block tree (widen the search) until
+ * we find something (i.e., we don't return ESRCH) and then search back
+ * down the tree (narrow the search) until we reach our original search
+ * level.
+ */
+static int
+dnode_next_offset_level(dnode_t *dn, int flags, uint64_t *offset,
+ int lvl, uint64_t blkfill, uint64_t txg)
+{
+ dmu_buf_impl_t *db = NULL;
+ void *data = NULL;
+ uint64_t epbs = dn->dn_phys->dn_indblkshift - SPA_BLKPTRSHIFT;
+ uint64_t epb = 1ULL << epbs;
+ uint64_t minfill, maxfill;
+ boolean_t hole;
+ int i, inc, error, span;
+
+ dprintf("probing object %llu offset %llx level %d of %u\n",
+ dn->dn_object, *offset, lvl, dn->dn_phys->dn_nlevels);
+
+ hole = ((flags & DNODE_FIND_HOLE) != 0);
+ inc = (flags & DNODE_FIND_BACKWARDS) ? -1 : 1;
+ ASSERT(txg == 0 || !hole);
+
+ if (lvl == dn->dn_phys->dn_nlevels) {
+ error = 0;
+ epb = dn->dn_phys->dn_nblkptr;
+ data = dn->dn_phys->dn_blkptr;
+ } else {
+ uint64_t blkid = dbuf_whichblock(dn, *offset) >> (epbs * lvl);
+ error = dbuf_hold_impl(dn, lvl, blkid, TRUE, FTAG, &db);
+ if (error) {
+ if (error != ENOENT)
+ return (error);
+ if (hole)
+ return (0);
+ /*
+ * This can only happen when we are searching up
+ * the block tree for data. We don't really need to
+ * adjust the offset, as we will just end up looking
+ * at the pointer to this block in its parent, and its
+ * going to be unallocated, so we will skip over it.
+ */
+ return (ESRCH);
+ }
+ error = dbuf_read(db, NULL, DB_RF_CANFAIL | DB_RF_HAVESTRUCT);
+ if (error) {
+ dbuf_rele(db, FTAG);
+ return (error);
+ }
+ data = db->db.db_data;
+ }
+
+ if (db && txg &&
+ (db->db_blkptr == NULL || db->db_blkptr->blk_birth <= txg)) {
+ /*
+ * This can only happen when we are searching up the tree
+ * and these conditions mean that we need to keep climbing.
+ */
+ error = ESRCH;
+ } else if (lvl == 0) {
+ dnode_phys_t *dnp = data;
+ span = DNODE_SHIFT;
+ ASSERT(dn->dn_type == DMU_OT_DNODE);
+
+ for (i = (*offset >> span) & (blkfill - 1);
+ i >= 0 && i < blkfill; i += inc) {
+ if ((dnp[i].dn_type == DMU_OT_NONE) == hole)
+ break;
+ *offset += (1ULL << span) * inc;
+ }
+ if (i < 0 || i == blkfill)
+ error = ESRCH;
+ } else {
+ blkptr_t *bp = data;
+ uint64_t start = *offset;
+ span = (lvl - 1) * epbs + dn->dn_datablkshift;
+ minfill = 0;
+ maxfill = blkfill << ((lvl - 1) * epbs);
+
+ if (hole)
+ maxfill--;
+ else
+ minfill++;
+
+ *offset = *offset >> span;
+ for (i = BF64_GET(*offset, 0, epbs);
+ i >= 0 && i < epb; i += inc) {
+ if (bp[i].blk_fill >= minfill &&
+ bp[i].blk_fill <= maxfill &&
+ (hole || bp[i].blk_birth > txg))
+ break;
+ if (inc > 0 || *offset > 0)
+ *offset += inc;
+ }
+ *offset = *offset << span;
+ if (inc < 0) {
+ /* traversing backwards; position offset at the end */
+ ASSERT3U(*offset, <=, start);
+ *offset = MIN(*offset + (1ULL << span) - 1, start);
+ } else if (*offset < start) {
+ *offset = start;
+ }
+ if (i < 0 || i >= epb)
+ error = ESRCH;
+ }
+
+ if (db)
+ dbuf_rele(db, FTAG);
+
+ return (error);
+}
+
+/*
+ * Find the next hole, data, or sparse region at or after *offset.
+ * The value 'blkfill' tells us how many items we expect to find
+ * in an L0 data block; this value is 1 for normal objects,
+ * DNODES_PER_BLOCK for the meta dnode, and some fraction of
+ * DNODES_PER_BLOCK when searching for sparse regions thereof.
+ *
+ * Examples:
+ *
+ * dnode_next_offset(dn, flags, offset, 1, 1, 0);
+ * Finds the next/previous hole/data in a file.
+ * Used in dmu_offset_next().
+ *
+ * dnode_next_offset(mdn, flags, offset, 0, DNODES_PER_BLOCK, txg);
+ * Finds the next free/allocated dnode an objset's meta-dnode.
+ * Only finds objects that have new contents since txg (ie.
+ * bonus buffer changes and content removal are ignored).
+ * Used in dmu_object_next().
+ *
+ * dnode_next_offset(mdn, DNODE_FIND_HOLE, offset, 2, DNODES_PER_BLOCK >> 2, 0);
+ * Finds the next L2 meta-dnode bp that's at most 1/4 full.
+ * Used in dmu_object_alloc().
+ */
+int
+dnode_next_offset(dnode_t *dn, int flags, uint64_t *offset,
+ int minlvl, uint64_t blkfill, uint64_t txg)
+{
+ uint64_t initial_offset = *offset;
+ int lvl, maxlvl;
+ int error = 0;
+
+ if (!(flags & DNODE_FIND_HAVELOCK))
+ rw_enter(&dn->dn_struct_rwlock, RW_READER);
+
+ if (dn->dn_phys->dn_nlevels == 0) {
+ error = ESRCH;
+ goto out;
+ }
+
+ if (dn->dn_datablkshift == 0) {
+ if (*offset < dn->dn_datablksz) {
+ if (flags & DNODE_FIND_HOLE)
+ *offset = dn->dn_datablksz;
+ } else {
+ error = ESRCH;
+ }
+ goto out;
+ }
+
+ maxlvl = dn->dn_phys->dn_nlevels;
+
+ for (lvl = minlvl; lvl <= maxlvl; lvl++) {
+ error = dnode_next_offset_level(dn,
+ flags, offset, lvl, blkfill, txg);
+ if (error != ESRCH)
+ break;
+ }
+
+ while (error == 0 && --lvl >= minlvl) {
+ error = dnode_next_offset_level(dn,
+ flags, offset, lvl, blkfill, txg);
+ }
+
+ if (error == 0 && (flags & DNODE_FIND_BACKWARDS ?
+ initial_offset < *offset : initial_offset > *offset))
+ error = ESRCH;
+out:
+ if (!(flags & DNODE_FIND_HAVELOCK))
+ rw_exit(&dn->dn_struct_rwlock);
+
+ return (error);
+}