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-rw-r--r--module/zfs/dmu.c1227
1 files changed, 1227 insertions, 0 deletions
diff --git a/module/zfs/dmu.c b/module/zfs/dmu.c
new file mode 100644
index 000000000..b6205bd50
--- /dev/null
+++ b/module/zfs/dmu.c
@@ -0,0 +1,1227 @@
+/*
+ * 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/dmu.h>
+#include <sys/dmu_impl.h>
+#include <sys/dmu_tx.h>
+#include <sys/dbuf.h>
+#include <sys/dnode.h>
+#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/dsl_synctask.h>
+#include <sys/dsl_prop.h>
+#include <sys/dmu_zfetch.h>
+#include <sys/zfs_ioctl.h>
+#include <sys/zap.h>
+#include <sys/zio_checksum.h>
+#ifdef _KERNEL
+#include <sys/vmsystm.h>
+#include <sys/zfs_znode.h>
+#endif
+
+const dmu_object_type_info_t dmu_ot[DMU_OT_NUMTYPES] = {
+ { byteswap_uint8_array, TRUE, "unallocated" },
+ { zap_byteswap, TRUE, "object directory" },
+ { byteswap_uint64_array, TRUE, "object array" },
+ { byteswap_uint8_array, TRUE, "packed nvlist" },
+ { byteswap_uint64_array, TRUE, "packed nvlist size" },
+ { byteswap_uint64_array, TRUE, "bplist" },
+ { byteswap_uint64_array, TRUE, "bplist header" },
+ { byteswap_uint64_array, TRUE, "SPA space map header" },
+ { byteswap_uint64_array, TRUE, "SPA space map" },
+ { byteswap_uint64_array, TRUE, "ZIL intent log" },
+ { dnode_buf_byteswap, TRUE, "DMU dnode" },
+ { dmu_objset_byteswap, TRUE, "DMU objset" },
+ { byteswap_uint64_array, TRUE, "DSL directory" },
+ { zap_byteswap, TRUE, "DSL directory child map"},
+ { zap_byteswap, TRUE, "DSL dataset snap map" },
+ { zap_byteswap, TRUE, "DSL props" },
+ { byteswap_uint64_array, TRUE, "DSL dataset" },
+ { zfs_znode_byteswap, TRUE, "ZFS znode" },
+ { zfs_oldacl_byteswap, TRUE, "ZFS V0 ACL" },
+ { byteswap_uint8_array, FALSE, "ZFS plain file" },
+ { zap_byteswap, TRUE, "ZFS directory" },
+ { zap_byteswap, TRUE, "ZFS master node" },
+ { zap_byteswap, TRUE, "ZFS delete queue" },
+ { byteswap_uint8_array, FALSE, "zvol object" },
+ { zap_byteswap, TRUE, "zvol prop" },
+ { byteswap_uint8_array, FALSE, "other uint8[]" },
+ { byteswap_uint64_array, FALSE, "other uint64[]" },
+ { zap_byteswap, TRUE, "other ZAP" },
+ { zap_byteswap, TRUE, "persistent error log" },
+ { byteswap_uint8_array, TRUE, "SPA history" },
+ { byteswap_uint64_array, TRUE, "SPA history offsets" },
+ { zap_byteswap, TRUE, "Pool properties" },
+ { zap_byteswap, TRUE, "DSL permissions" },
+ { zfs_acl_byteswap, TRUE, "ZFS ACL" },
+ { byteswap_uint8_array, TRUE, "ZFS SYSACL" },
+ { byteswap_uint8_array, TRUE, "FUID table" },
+ { byteswap_uint64_array, TRUE, "FUID table size" },
+ { zap_byteswap, TRUE, "DSL dataset next clones"},
+ { zap_byteswap, TRUE, "scrub work queue" },
+};
+
+int
+dmu_buf_hold(objset_t *os, uint64_t object, uint64_t offset,
+ void *tag, dmu_buf_t **dbp)
+{
+ dnode_t *dn;
+ uint64_t blkid;
+ dmu_buf_impl_t *db;
+ int err;
+
+ err = dnode_hold(os->os, object, FTAG, &dn);
+ if (err)
+ return (err);
+ blkid = dbuf_whichblock(dn, offset);
+ rw_enter(&dn->dn_struct_rwlock, RW_READER);
+ db = dbuf_hold(dn, blkid, tag);
+ rw_exit(&dn->dn_struct_rwlock);
+ if (db == NULL) {
+ err = EIO;
+ } else {
+ err = dbuf_read(db, NULL, DB_RF_CANFAIL);
+ if (err) {
+ dbuf_rele(db, tag);
+ db = NULL;
+ }
+ }
+
+ dnode_rele(dn, FTAG);
+ *dbp = &db->db;
+ return (err);
+}
+
+int
+dmu_bonus_max(void)
+{
+ return (DN_MAX_BONUSLEN);
+}
+
+int
+dmu_set_bonus(dmu_buf_t *db, int newsize, dmu_tx_t *tx)
+{
+ dnode_t *dn = ((dmu_buf_impl_t *)db)->db_dnode;
+
+ if (dn->dn_bonus != (dmu_buf_impl_t *)db)
+ return (EINVAL);
+ if (newsize < 0 || newsize > db->db_size)
+ return (EINVAL);
+ dnode_setbonuslen(dn, newsize, tx);
+ return (0);
+}
+
+/*
+ * returns ENOENT, EIO, or 0.
+ */
+int
+dmu_bonus_hold(objset_t *os, uint64_t object, void *tag, dmu_buf_t **dbp)
+{
+ dnode_t *dn;
+ dmu_buf_impl_t *db;
+ int error;
+
+ error = dnode_hold(os->os, object, FTAG, &dn);
+ if (error)
+ return (error);
+
+ rw_enter(&dn->dn_struct_rwlock, RW_READER);
+ if (dn->dn_bonus == NULL) {
+ rw_exit(&dn->dn_struct_rwlock);
+ rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
+ if (dn->dn_bonus == NULL)
+ dbuf_create_bonus(dn);
+ }
+ db = dn->dn_bonus;
+ rw_exit(&dn->dn_struct_rwlock);
+
+ /* as long as the bonus buf is held, the dnode will be held */
+ if (refcount_add(&db->db_holds, tag) == 1)
+ VERIFY(dnode_add_ref(dn, db));
+
+ dnode_rele(dn, FTAG);
+
+ VERIFY(0 == dbuf_read(db, NULL, DB_RF_MUST_SUCCEED));
+
+ *dbp = &db->db;
+ return (0);
+}
+
+/*
+ * Note: longer-term, we should modify all of the dmu_buf_*() interfaces
+ * to take a held dnode rather than <os, object> -- the lookup is wasteful,
+ * and can induce severe lock contention when writing to several files
+ * whose dnodes are in the same block.
+ */
+static int
+dmu_buf_hold_array_by_dnode(dnode_t *dn, uint64_t offset,
+ uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp)
+{
+ dsl_pool_t *dp = NULL;
+ dmu_buf_t **dbp;
+ uint64_t blkid, nblks, i;
+ uint32_t flags;
+ int err;
+ zio_t *zio;
+ hrtime_t start;
+
+ ASSERT(length <= DMU_MAX_ACCESS);
+
+ flags = DB_RF_CANFAIL | DB_RF_NEVERWAIT;
+ if (length > zfetch_array_rd_sz)
+ flags |= DB_RF_NOPREFETCH;
+
+ rw_enter(&dn->dn_struct_rwlock, RW_READER);
+ if (dn->dn_datablkshift) {
+ int blkshift = dn->dn_datablkshift;
+ nblks = (P2ROUNDUP(offset+length, 1ULL<<blkshift) -
+ P2ALIGN(offset, 1ULL<<blkshift)) >> blkshift;
+ } else {
+ if (offset + length > dn->dn_datablksz) {
+ zfs_panic_recover("zfs: accessing past end of object "
+ "%llx/%llx (size=%u access=%llu+%llu)",
+ (longlong_t)dn->dn_objset->
+ os_dsl_dataset->ds_object,
+ (longlong_t)dn->dn_object, dn->dn_datablksz,
+ (longlong_t)offset, (longlong_t)length);
+ return (EIO);
+ }
+ nblks = 1;
+ }
+ dbp = kmem_zalloc(sizeof (dmu_buf_t *) * nblks, KM_SLEEP);
+
+ if (dn->dn_objset->os_dsl_dataset)
+ dp = dn->dn_objset->os_dsl_dataset->ds_dir->dd_pool;
+ if (dp && dsl_pool_sync_context(dp))
+ start = gethrtime();
+ zio = zio_root(dn->dn_objset->os_spa, NULL, NULL, ZIO_FLAG_CANFAIL);
+ blkid = dbuf_whichblock(dn, offset);
+ for (i = 0; i < nblks; i++) {
+ dmu_buf_impl_t *db = dbuf_hold(dn, blkid+i, tag);
+ if (db == NULL) {
+ rw_exit(&dn->dn_struct_rwlock);
+ dmu_buf_rele_array(dbp, nblks, tag);
+ zio_nowait(zio);
+ return (EIO);
+ }
+ /* initiate async i/o */
+ if (read) {
+ rw_exit(&dn->dn_struct_rwlock);
+ (void) dbuf_read(db, zio, flags);
+ rw_enter(&dn->dn_struct_rwlock, RW_READER);
+ }
+ dbp[i] = &db->db;
+ }
+ rw_exit(&dn->dn_struct_rwlock);
+
+ /* wait for async i/o */
+ err = zio_wait(zio);
+ /* track read overhead when we are in sync context */
+ if (dp && dsl_pool_sync_context(dp))
+ dp->dp_read_overhead += gethrtime() - start;
+ if (err) {
+ dmu_buf_rele_array(dbp, nblks, tag);
+ return (err);
+ }
+
+ /* wait for other io to complete */
+ if (read) {
+ for (i = 0; i < nblks; i++) {
+ dmu_buf_impl_t *db = (dmu_buf_impl_t *)dbp[i];
+ mutex_enter(&db->db_mtx);
+ while (db->db_state == DB_READ ||
+ db->db_state == DB_FILL)
+ cv_wait(&db->db_changed, &db->db_mtx);
+ if (db->db_state == DB_UNCACHED)
+ err = EIO;
+ mutex_exit(&db->db_mtx);
+ if (err) {
+ dmu_buf_rele_array(dbp, nblks, tag);
+ return (err);
+ }
+ }
+ }
+
+ *numbufsp = nblks;
+ *dbpp = dbp;
+ return (0);
+}
+
+static int
+dmu_buf_hold_array(objset_t *os, uint64_t object, uint64_t offset,
+ uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp)
+{
+ dnode_t *dn;
+ int err;
+
+ err = dnode_hold(os->os, object, FTAG, &dn);
+ if (err)
+ return (err);
+
+ err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag,
+ numbufsp, dbpp);
+
+ dnode_rele(dn, FTAG);
+
+ return (err);
+}
+
+int
+dmu_buf_hold_array_by_bonus(dmu_buf_t *db, uint64_t offset,
+ uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp)
+{
+ dnode_t *dn = ((dmu_buf_impl_t *)db)->db_dnode;
+ int err;
+
+ err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag,
+ numbufsp, dbpp);
+
+ return (err);
+}
+
+void
+dmu_buf_rele_array(dmu_buf_t **dbp_fake, int numbufs, void *tag)
+{
+ int i;
+ dmu_buf_impl_t **dbp = (dmu_buf_impl_t **)dbp_fake;
+
+ if (numbufs == 0)
+ return;
+
+ for (i = 0; i < numbufs; i++) {
+ if (dbp[i])
+ dbuf_rele(dbp[i], tag);
+ }
+
+ kmem_free(dbp, sizeof (dmu_buf_t *) * numbufs);
+}
+
+void
+dmu_prefetch(objset_t *os, uint64_t object, uint64_t offset, uint64_t len)
+{
+ dnode_t *dn;
+ uint64_t blkid;
+ int nblks, i, err;
+
+ if (zfs_prefetch_disable)
+ return;
+
+ if (len == 0) { /* they're interested in the bonus buffer */
+ dn = os->os->os_meta_dnode;
+
+ if (object == 0 || object >= DN_MAX_OBJECT)
+ return;
+
+ rw_enter(&dn->dn_struct_rwlock, RW_READER);
+ blkid = dbuf_whichblock(dn, object * sizeof (dnode_phys_t));
+ dbuf_prefetch(dn, blkid);
+ rw_exit(&dn->dn_struct_rwlock);
+ return;
+ }
+
+ /*
+ * XXX - Note, if the dnode for the requested object is not
+ * already cached, we will do a *synchronous* read in the
+ * dnode_hold() call. The same is true for any indirects.
+ */
+ err = dnode_hold(os->os, object, FTAG, &dn);
+ if (err != 0)
+ return;
+
+ rw_enter(&dn->dn_struct_rwlock, RW_READER);
+ if (dn->dn_datablkshift) {
+ int blkshift = dn->dn_datablkshift;
+ nblks = (P2ROUNDUP(offset+len, 1<<blkshift) -
+ P2ALIGN(offset, 1<<blkshift)) >> blkshift;
+ } else {
+ nblks = (offset < dn->dn_datablksz);
+ }
+
+ if (nblks != 0) {
+ blkid = dbuf_whichblock(dn, offset);
+ for (i = 0; i < nblks; i++)
+ dbuf_prefetch(dn, blkid+i);
+ }
+
+ rw_exit(&dn->dn_struct_rwlock);
+
+ dnode_rele(dn, FTAG);
+}
+
+static int
+get_next_chunk(dnode_t *dn, uint64_t *offset, uint64_t limit)
+{
+ uint64_t len = *offset - limit;
+ uint64_t chunk_len = dn->dn_datablksz * DMU_MAX_DELETEBLKCNT;
+ uint64_t subchunk =
+ dn->dn_datablksz * EPB(dn->dn_indblkshift, SPA_BLKPTRSHIFT);
+
+ ASSERT(limit <= *offset);
+
+ if (len <= chunk_len) {
+ *offset = limit;
+ return (0);
+ }
+
+ ASSERT(ISP2(subchunk));
+
+ while (*offset > limit) {
+ uint64_t initial_offset = P2ROUNDUP(*offset, subchunk);
+ uint64_t delta;
+ int err;
+
+ /* skip over allocated data */
+ err = dnode_next_offset(dn,
+ DNODE_FIND_HOLE|DNODE_FIND_BACKWARDS, offset, 1, 1, 0);
+ if (err == ESRCH)
+ *offset = limit;
+ else if (err)
+ return (err);
+
+ ASSERT3U(*offset, <=, initial_offset);
+ *offset = P2ALIGN(*offset, subchunk);
+ delta = initial_offset - *offset;
+ if (delta >= chunk_len) {
+ *offset += delta - chunk_len;
+ return (0);
+ }
+ chunk_len -= delta;
+
+ /* skip over unallocated data */
+ err = dnode_next_offset(dn,
+ DNODE_FIND_BACKWARDS, offset, 1, 1, 0);
+ if (err == ESRCH)
+ *offset = limit;
+ else if (err)
+ return (err);
+
+ if (*offset < limit)
+ *offset = limit;
+ ASSERT3U(*offset, <, initial_offset);
+ }
+ return (0);
+}
+
+static int
+dmu_free_long_range_impl(objset_t *os, dnode_t *dn, uint64_t offset,
+ uint64_t length, boolean_t free_dnode)
+{
+ dmu_tx_t *tx;
+ uint64_t object_size, start, end, len;
+ boolean_t trunc = (length == DMU_OBJECT_END);
+ int align, err;
+
+ align = 1 << dn->dn_datablkshift;
+ ASSERT(align > 0);
+ object_size = align == 1 ? dn->dn_datablksz :
+ (dn->dn_maxblkid + 1) << dn->dn_datablkshift;
+
+ if (trunc || (end = offset + length) > object_size)
+ end = object_size;
+ if (end <= offset)
+ return (0);
+ length = end - offset;
+
+ while (length) {
+ start = end;
+ err = get_next_chunk(dn, &start, offset);
+ if (err)
+ return (err);
+ len = trunc ? DMU_OBJECT_END : end - start;
+
+ tx = dmu_tx_create(os);
+ dmu_tx_hold_free(tx, dn->dn_object, start, len);
+ err = dmu_tx_assign(tx, TXG_WAIT);
+ if (err) {
+ dmu_tx_abort(tx);
+ return (err);
+ }
+
+ dnode_free_range(dn, start, trunc ? -1 : len, tx);
+
+ if (start == 0 && free_dnode) {
+ ASSERT(trunc);
+ dnode_free(dn, tx);
+ }
+
+ length -= end - start;
+
+ dmu_tx_commit(tx);
+ end = start;
+ }
+ return (0);
+}
+
+int
+dmu_free_long_range(objset_t *os, uint64_t object,
+ uint64_t offset, uint64_t length)
+{
+ dnode_t *dn;
+ int err;
+
+ err = dnode_hold(os->os, object, FTAG, &dn);
+ if (err != 0)
+ return (err);
+ err = dmu_free_long_range_impl(os, dn, offset, length, FALSE);
+ dnode_rele(dn, FTAG);
+ return (err);
+}
+
+int
+dmu_free_object(objset_t *os, uint64_t object)
+{
+ dnode_t *dn;
+ dmu_tx_t *tx;
+ int err;
+
+ err = dnode_hold_impl(os->os, object, DNODE_MUST_BE_ALLOCATED,
+ FTAG, &dn);
+ if (err != 0)
+ return (err);
+ if (dn->dn_nlevels == 1) {
+ tx = dmu_tx_create(os);
+ dmu_tx_hold_bonus(tx, object);
+ dmu_tx_hold_free(tx, dn->dn_object, 0, DMU_OBJECT_END);
+ err = dmu_tx_assign(tx, TXG_WAIT);
+ if (err == 0) {
+ dnode_free_range(dn, 0, DMU_OBJECT_END, tx);
+ dnode_free(dn, tx);
+ dmu_tx_commit(tx);
+ } else {
+ dmu_tx_abort(tx);
+ }
+ } else {
+ err = dmu_free_long_range_impl(os, dn, 0, DMU_OBJECT_END, TRUE);
+ }
+ dnode_rele(dn, FTAG);
+ return (err);
+}
+
+int
+dmu_free_range(objset_t *os, uint64_t object, uint64_t offset,
+ uint64_t size, dmu_tx_t *tx)
+{
+ dnode_t *dn;
+ int err = dnode_hold(os->os, object, FTAG, &dn);
+ if (err)
+ return (err);
+ ASSERT(offset < UINT64_MAX);
+ ASSERT(size == -1ULL || size <= UINT64_MAX - offset);
+ dnode_free_range(dn, offset, size, tx);
+ dnode_rele(dn, FTAG);
+ return (0);
+}
+
+int
+dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
+ void *buf)
+{
+ dnode_t *dn;
+ dmu_buf_t **dbp;
+ int numbufs, i, err;
+
+ err = dnode_hold(os->os, object, FTAG, &dn);
+ if (err)
+ return (err);
+
+ /*
+ * Deal with odd block sizes, where there can't be data past the first
+ * block. If we ever do the tail block optimization, we will need to
+ * handle that here as well.
+ */
+ if (dn->dn_datablkshift == 0) {
+ int newsz = offset > dn->dn_datablksz ? 0 :
+ MIN(size, dn->dn_datablksz - offset);
+ bzero((char *)buf + newsz, size - newsz);
+ size = newsz;
+ }
+
+ while (size > 0) {
+ uint64_t mylen = MIN(size, DMU_MAX_ACCESS / 2);
+
+ /*
+ * NB: we could do this block-at-a-time, but it's nice
+ * to be reading in parallel.
+ */
+ err = dmu_buf_hold_array_by_dnode(dn, offset, mylen,
+ TRUE, FTAG, &numbufs, &dbp);
+ if (err)
+ break;
+
+ for (i = 0; i < numbufs; i++) {
+ int tocpy;
+ int bufoff;
+ dmu_buf_t *db = dbp[i];
+
+ ASSERT(size > 0);
+
+ bufoff = offset - db->db_offset;
+ tocpy = (int)MIN(db->db_size - bufoff, size);
+
+ bcopy((char *)db->db_data + bufoff, buf, tocpy);
+
+ offset += tocpy;
+ size -= tocpy;
+ buf = (char *)buf + tocpy;
+ }
+ dmu_buf_rele_array(dbp, numbufs, FTAG);
+ }
+ dnode_rele(dn, FTAG);
+ return (err);
+}
+
+void
+dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
+ const void *buf, dmu_tx_t *tx)
+{
+ dmu_buf_t **dbp;
+ int numbufs, i;
+
+ if (size == 0)
+ return;
+
+ VERIFY(0 == dmu_buf_hold_array(os, object, offset, size,
+ FALSE, FTAG, &numbufs, &dbp));
+
+ for (i = 0; i < numbufs; i++) {
+ int tocpy;
+ int bufoff;
+ dmu_buf_t *db = dbp[i];
+
+ ASSERT(size > 0);
+
+ bufoff = offset - db->db_offset;
+ tocpy = (int)MIN(db->db_size - bufoff, size);
+
+ ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size);
+
+ if (tocpy == db->db_size)
+ dmu_buf_will_fill(db, tx);
+ else
+ dmu_buf_will_dirty(db, tx);
+
+ bcopy(buf, (char *)db->db_data + bufoff, tocpy);
+
+ if (tocpy == db->db_size)
+ dmu_buf_fill_done(db, tx);
+
+ offset += tocpy;
+ size -= tocpy;
+ buf = (char *)buf + tocpy;
+ }
+ dmu_buf_rele_array(dbp, numbufs, FTAG);
+}
+
+void
+dmu_prealloc(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
+ dmu_tx_t *tx)
+{
+ dmu_buf_t **dbp;
+ int numbufs, i;
+
+ if (size == 0)
+ return;
+
+ VERIFY(0 == dmu_buf_hold_array(os, object, offset, size,
+ FALSE, FTAG, &numbufs, &dbp));
+
+ for (i = 0; i < numbufs; i++) {
+ dmu_buf_t *db = dbp[i];
+
+ dmu_buf_will_not_fill(db, tx);
+ }
+ dmu_buf_rele_array(dbp, numbufs, FTAG);
+}
+
+#ifdef _KERNEL
+int
+dmu_read_uio(objset_t *os, uint64_t object, uio_t *uio, uint64_t size)
+{
+ dmu_buf_t **dbp;
+ int numbufs, i, err;
+
+ /*
+ * NB: we could do this block-at-a-time, but it's nice
+ * to be reading in parallel.
+ */
+ err = dmu_buf_hold_array(os, object, uio->uio_loffset, size, TRUE, FTAG,
+ &numbufs, &dbp);
+ if (err)
+ return (err);
+
+ for (i = 0; i < numbufs; i++) {
+ int tocpy;
+ int bufoff;
+ dmu_buf_t *db = dbp[i];
+
+ ASSERT(size > 0);
+
+ bufoff = uio->uio_loffset - db->db_offset;
+ tocpy = (int)MIN(db->db_size - bufoff, size);
+
+ err = uiomove((char *)db->db_data + bufoff, tocpy,
+ UIO_READ, uio);
+ if (err)
+ break;
+
+ size -= tocpy;
+ }
+ dmu_buf_rele_array(dbp, numbufs, FTAG);
+
+ return (err);
+}
+
+int
+dmu_write_uio(objset_t *os, uint64_t object, uio_t *uio, uint64_t size,
+ dmu_tx_t *tx)
+{
+ dmu_buf_t **dbp;
+ int numbufs, i;
+ int err = 0;
+
+ if (size == 0)
+ return (0);
+
+ err = dmu_buf_hold_array(os, object, uio->uio_loffset, size,
+ FALSE, FTAG, &numbufs, &dbp);
+ if (err)
+ return (err);
+
+ for (i = 0; i < numbufs; i++) {
+ int tocpy;
+ int bufoff;
+ dmu_buf_t *db = dbp[i];
+
+ ASSERT(size > 0);
+
+ bufoff = uio->uio_loffset - db->db_offset;
+ tocpy = (int)MIN(db->db_size - bufoff, size);
+
+ ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size);
+
+ if (tocpy == db->db_size)
+ dmu_buf_will_fill(db, tx);
+ else
+ dmu_buf_will_dirty(db, tx);
+
+ /*
+ * XXX uiomove could block forever (eg. nfs-backed
+ * pages). There needs to be a uiolockdown() function
+ * to lock the pages in memory, so that uiomove won't
+ * block.
+ */
+ err = uiomove((char *)db->db_data + bufoff, tocpy,
+ UIO_WRITE, uio);
+
+ if (tocpy == db->db_size)
+ dmu_buf_fill_done(db, tx);
+
+ if (err)
+ break;
+
+ size -= tocpy;
+ }
+ dmu_buf_rele_array(dbp, numbufs, FTAG);
+ return (err);
+}
+
+int
+dmu_write_pages(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
+ page_t *pp, dmu_tx_t *tx)
+{
+ dmu_buf_t **dbp;
+ int numbufs, i;
+ int err;
+
+ if (size == 0)
+ return (0);
+
+ err = dmu_buf_hold_array(os, object, offset, size,
+ FALSE, FTAG, &numbufs, &dbp);
+ if (err)
+ return (err);
+
+ for (i = 0; i < numbufs; i++) {
+ int tocpy, copied, thiscpy;
+ int bufoff;
+ dmu_buf_t *db = dbp[i];
+ caddr_t va;
+
+ ASSERT(size > 0);
+ ASSERT3U(db->db_size, >=, PAGESIZE);
+
+ bufoff = offset - db->db_offset;
+ tocpy = (int)MIN(db->db_size - bufoff, size);
+
+ ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size);
+
+ if (tocpy == db->db_size)
+ dmu_buf_will_fill(db, tx);
+ else
+ dmu_buf_will_dirty(db, tx);
+
+ for (copied = 0; copied < tocpy; copied += PAGESIZE) {
+ ASSERT3U(pp->p_offset, ==, db->db_offset + bufoff);
+ thiscpy = MIN(PAGESIZE, tocpy - copied);
+ va = zfs_map_page(pp, S_READ);
+ bcopy(va, (char *)db->db_data + bufoff, thiscpy);
+ zfs_unmap_page(pp, va);
+ pp = pp->p_next;
+ bufoff += PAGESIZE;
+ }
+
+ if (tocpy == db->db_size)
+ dmu_buf_fill_done(db, tx);
+
+ if (err)
+ break;
+
+ offset += tocpy;
+ size -= tocpy;
+ }
+ dmu_buf_rele_array(dbp, numbufs, FTAG);
+ return (err);
+}
+#endif
+
+typedef struct {
+ dbuf_dirty_record_t *dr;
+ dmu_sync_cb_t *done;
+ void *arg;
+} dmu_sync_arg_t;
+
+/* ARGSUSED */
+static void
+dmu_sync_ready(zio_t *zio, arc_buf_t *buf, void *varg)
+{
+ blkptr_t *bp = zio->io_bp;
+
+ if (!BP_IS_HOLE(bp)) {
+ dmu_sync_arg_t *in = varg;
+ dbuf_dirty_record_t *dr = in->dr;
+ dmu_buf_impl_t *db = dr->dr_dbuf;
+ ASSERT(BP_GET_TYPE(bp) == db->db_dnode->dn_type);
+ ASSERT(BP_GET_LEVEL(bp) == 0);
+ bp->blk_fill = 1;
+ }
+}
+
+/* ARGSUSED */
+static void
+dmu_sync_done(zio_t *zio, arc_buf_t *buf, void *varg)
+{
+ dmu_sync_arg_t *in = varg;
+ dbuf_dirty_record_t *dr = in->dr;
+ dmu_buf_impl_t *db = dr->dr_dbuf;
+ dmu_sync_cb_t *done = in->done;
+
+ mutex_enter(&db->db_mtx);
+ ASSERT(dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC);
+ dr->dt.dl.dr_overridden_by = *zio->io_bp; /* structure assignment */
+ dr->dt.dl.dr_override_state = DR_OVERRIDDEN;
+ cv_broadcast(&db->db_changed);
+ mutex_exit(&db->db_mtx);
+
+ if (done)
+ done(&(db->db), in->arg);
+
+ kmem_free(in, sizeof (dmu_sync_arg_t));
+}
+
+/*
+ * Intent log support: sync the block associated with db to disk.
+ * N.B. and XXX: the caller is responsible for making sure that the
+ * data isn't changing while dmu_sync() is writing it.
+ *
+ * Return values:
+ *
+ * EEXIST: this txg has already been synced, so there's nothing to to.
+ * The caller should not log the write.
+ *
+ * ENOENT: the block was dbuf_free_range()'d, so there's nothing to do.
+ * The caller should not log the write.
+ *
+ * EALREADY: this block is already in the process of being synced.
+ * The caller should track its progress (somehow).
+ *
+ * EINPROGRESS: the IO has been initiated.
+ * The caller should log this blkptr in the callback.
+ *
+ * 0: completed. Sets *bp to the blkptr just written.
+ * The caller should log this blkptr immediately.
+ */
+int
+dmu_sync(zio_t *pio, dmu_buf_t *db_fake,
+ blkptr_t *bp, uint64_t txg, dmu_sync_cb_t *done, void *arg)
+{
+ dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
+ objset_impl_t *os = db->db_objset;
+ dsl_pool_t *dp = os->os_dsl_dataset->ds_dir->dd_pool;
+ tx_state_t *tx = &dp->dp_tx;
+ dbuf_dirty_record_t *dr;
+ dmu_sync_arg_t *in;
+ zbookmark_t zb;
+ writeprops_t wp = { 0 };
+ zio_t *zio;
+ int err;
+
+ ASSERT(BP_IS_HOLE(bp));
+ ASSERT(txg != 0);
+
+ dprintf("dmu_sync txg=%llu, s,o,q %llu %llu %llu\n",
+ txg, tx->tx_synced_txg, tx->tx_open_txg, tx->tx_quiesced_txg);
+
+ /*
+ * XXX - would be nice if we could do this without suspending...
+ */
+ txg_suspend(dp);
+
+ /*
+ * If this txg already synced, there's nothing to do.
+ */
+ if (txg <= tx->tx_synced_txg) {
+ txg_resume(dp);
+ /*
+ * If we're running ziltest, we need the blkptr regardless.
+ */
+ if (txg > spa_freeze_txg(dp->dp_spa)) {
+ /* if db_blkptr == NULL, this was an empty write */
+ if (db->db_blkptr)
+ *bp = *db->db_blkptr; /* structure assignment */
+ return (0);
+ }
+ return (EEXIST);
+ }
+
+ mutex_enter(&db->db_mtx);
+
+ if (txg == tx->tx_syncing_txg) {
+ while (db->db_data_pending) {
+ /*
+ * IO is in-progress. Wait for it to finish.
+ * XXX - would be nice to be able to somehow "attach"
+ * this zio to the parent zio passed in.
+ */
+ cv_wait(&db->db_changed, &db->db_mtx);
+ if (!db->db_data_pending &&
+ db->db_blkptr && BP_IS_HOLE(db->db_blkptr)) {
+ /*
+ * IO was compressed away
+ */
+ *bp = *db->db_blkptr; /* structure assignment */
+ mutex_exit(&db->db_mtx);
+ txg_resume(dp);
+ return (0);
+ }
+ ASSERT(db->db_data_pending ||
+ (db->db_blkptr && db->db_blkptr->blk_birth == txg));
+ }
+
+ if (db->db_blkptr && db->db_blkptr->blk_birth == txg) {
+ /*
+ * IO is already completed.
+ */
+ *bp = *db->db_blkptr; /* structure assignment */
+ mutex_exit(&db->db_mtx);
+ txg_resume(dp);
+ return (0);
+ }
+ }
+
+ dr = db->db_last_dirty;
+ while (dr && dr->dr_txg > txg)
+ dr = dr->dr_next;
+ if (dr == NULL || dr->dr_txg < txg) {
+ /*
+ * This dbuf isn't dirty, must have been free_range'd.
+ * There's no need to log writes to freed blocks, so we're done.
+ */
+ mutex_exit(&db->db_mtx);
+ txg_resume(dp);
+ return (ENOENT);
+ }
+
+ ASSERT(dr->dr_txg == txg);
+ if (dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC) {
+ /*
+ * We have already issued a sync write for this buffer.
+ */
+ mutex_exit(&db->db_mtx);
+ txg_resume(dp);
+ return (EALREADY);
+ } else if (dr->dt.dl.dr_override_state == DR_OVERRIDDEN) {
+ /*
+ * This buffer has already been synced. It could not
+ * have been dirtied since, or we would have cleared the state.
+ */
+ *bp = dr->dt.dl.dr_overridden_by; /* structure assignment */
+ mutex_exit(&db->db_mtx);
+ txg_resume(dp);
+ return (0);
+ }
+
+ dr->dt.dl.dr_override_state = DR_IN_DMU_SYNC;
+ in = kmem_alloc(sizeof (dmu_sync_arg_t), KM_SLEEP);
+ in->dr = dr;
+ in->done = done;
+ in->arg = arg;
+ mutex_exit(&db->db_mtx);
+ txg_resume(dp);
+
+ zb.zb_objset = os->os_dsl_dataset->ds_object;
+ zb.zb_object = db->db.db_object;
+ zb.zb_level = db->db_level;
+ zb.zb_blkid = db->db_blkid;
+
+ wp.wp_type = db->db_dnode->dn_type;
+ wp.wp_level = db->db_level;
+ wp.wp_copies = os->os_copies;
+ wp.wp_dnchecksum = db->db_dnode->dn_checksum;
+ wp.wp_oschecksum = os->os_checksum;
+ wp.wp_dncompress = db->db_dnode->dn_compress;
+ wp.wp_oscompress = os->os_compress;
+
+ ASSERT(BP_IS_HOLE(bp));
+
+ zio = arc_write(pio, os->os_spa, &wp, DBUF_IS_L2CACHEABLE(db),
+ txg, bp, dr->dt.dl.dr_data, dmu_sync_ready, dmu_sync_done, in,
+ ZIO_PRIORITY_SYNC_WRITE, ZIO_FLAG_MUSTSUCCEED, &zb);
+ if (pio) {
+ zio_nowait(zio);
+ err = EINPROGRESS;
+ } else {
+ err = zio_wait(zio);
+ ASSERT(err == 0);
+ }
+ return (err);
+}
+
+int
+dmu_object_set_blocksize(objset_t *os, uint64_t object, uint64_t size, int ibs,
+ dmu_tx_t *tx)
+{
+ dnode_t *dn;
+ int err;
+
+ err = dnode_hold(os->os, object, FTAG, &dn);
+ if (err)
+ return (err);
+ err = dnode_set_blksz(dn, size, ibs, tx);
+ dnode_rele(dn, FTAG);
+ return (err);
+}
+
+void
+dmu_object_set_checksum(objset_t *os, uint64_t object, uint8_t checksum,
+ dmu_tx_t *tx)
+{
+ dnode_t *dn;
+
+ /* XXX assumes dnode_hold will not get an i/o error */
+ (void) dnode_hold(os->os, object, FTAG, &dn);
+ ASSERT(checksum < ZIO_CHECKSUM_FUNCTIONS);
+ dn->dn_checksum = checksum;
+ dnode_setdirty(dn, tx);
+ dnode_rele(dn, FTAG);
+}
+
+void
+dmu_object_set_compress(objset_t *os, uint64_t object, uint8_t compress,
+ dmu_tx_t *tx)
+{
+ dnode_t *dn;
+
+ /* XXX assumes dnode_hold will not get an i/o error */
+ (void) dnode_hold(os->os, object, FTAG, &dn);
+ ASSERT(compress < ZIO_COMPRESS_FUNCTIONS);
+ dn->dn_compress = compress;
+ dnode_setdirty(dn, tx);
+ dnode_rele(dn, FTAG);
+}
+
+int
+dmu_offset_next(objset_t *os, uint64_t object, boolean_t hole, uint64_t *off)
+{
+ dnode_t *dn;
+ int i, err;
+
+ err = dnode_hold(os->os, object, FTAG, &dn);
+ if (err)
+ return (err);
+ /*
+ * Sync any current changes before
+ * we go trundling through the block pointers.
+ */
+ for (i = 0; i < TXG_SIZE; i++) {
+ if (list_link_active(&dn->dn_dirty_link[i]))
+ break;
+ }
+ if (i != TXG_SIZE) {
+ dnode_rele(dn, FTAG);
+ txg_wait_synced(dmu_objset_pool(os), 0);
+ err = dnode_hold(os->os, object, FTAG, &dn);
+ if (err)
+ return (err);
+ }
+
+ err = dnode_next_offset(dn, (hole ? DNODE_FIND_HOLE : 0), off, 1, 1, 0);
+ dnode_rele(dn, FTAG);
+
+ return (err);
+}
+
+void
+dmu_object_info_from_dnode(dnode_t *dn, dmu_object_info_t *doi)
+{
+ rw_enter(&dn->dn_struct_rwlock, RW_READER);
+ mutex_enter(&dn->dn_mtx);
+
+ doi->doi_data_block_size = dn->dn_datablksz;
+ doi->doi_metadata_block_size = dn->dn_indblkshift ?
+ 1ULL << dn->dn_indblkshift : 0;
+ doi->doi_indirection = dn->dn_nlevels;
+ doi->doi_checksum = dn->dn_checksum;
+ doi->doi_compress = dn->dn_compress;
+ doi->doi_physical_blks = (DN_USED_BYTES(dn->dn_phys) +
+ SPA_MINBLOCKSIZE/2) >> SPA_MINBLOCKSHIFT;
+ doi->doi_max_block_offset = dn->dn_phys->dn_maxblkid;
+ doi->doi_type = dn->dn_type;
+ doi->doi_bonus_size = dn->dn_bonuslen;
+ doi->doi_bonus_type = dn->dn_bonustype;
+
+ mutex_exit(&dn->dn_mtx);
+ rw_exit(&dn->dn_struct_rwlock);
+}
+
+/*
+ * Get information on a DMU object.
+ * If doi is NULL, just indicates whether the object exists.
+ */
+int
+dmu_object_info(objset_t *os, uint64_t object, dmu_object_info_t *doi)
+{
+ dnode_t *dn;
+ int err = dnode_hold(os->os, object, FTAG, &dn);
+
+ if (err)
+ return (err);
+
+ if (doi != NULL)
+ dmu_object_info_from_dnode(dn, doi);
+
+ dnode_rele(dn, FTAG);
+ return (0);
+}
+
+/*
+ * As above, but faster; can be used when you have a held dbuf in hand.
+ */
+void
+dmu_object_info_from_db(dmu_buf_t *db, dmu_object_info_t *doi)
+{
+ dmu_object_info_from_dnode(((dmu_buf_impl_t *)db)->db_dnode, doi);
+}
+
+/*
+ * Faster still when you only care about the size.
+ * This is specifically optimized for zfs_getattr().
+ */
+void
+dmu_object_size_from_db(dmu_buf_t *db, uint32_t *blksize, u_longlong_t *nblk512)
+{
+ dnode_t *dn = ((dmu_buf_impl_t *)db)->db_dnode;
+
+ *blksize = dn->dn_datablksz;
+ /* add 1 for dnode space */
+ *nblk512 = ((DN_USED_BYTES(dn->dn_phys) + SPA_MINBLOCKSIZE/2) >>
+ SPA_MINBLOCKSHIFT) + 1;
+}
+
+void
+byteswap_uint64_array(void *vbuf, size_t size)
+{
+ uint64_t *buf = vbuf;
+ size_t count = size >> 3;
+ int i;
+
+ ASSERT((size & 7) == 0);
+
+ for (i = 0; i < count; i++)
+ buf[i] = BSWAP_64(buf[i]);
+}
+
+void
+byteswap_uint32_array(void *vbuf, size_t size)
+{
+ uint32_t *buf = vbuf;
+ size_t count = size >> 2;
+ int i;
+
+ ASSERT((size & 3) == 0);
+
+ for (i = 0; i < count; i++)
+ buf[i] = BSWAP_32(buf[i]);
+}
+
+void
+byteswap_uint16_array(void *vbuf, size_t size)
+{
+ uint16_t *buf = vbuf;
+ size_t count = size >> 1;
+ int i;
+
+ ASSERT((size & 1) == 0);
+
+ for (i = 0; i < count; i++)
+ buf[i] = BSWAP_16(buf[i]);
+}
+
+/* ARGSUSED */
+void
+byteswap_uint8_array(void *vbuf, size_t size)
+{
+}
+
+void
+dmu_init(void)
+{
+ dbuf_init();
+ dnode_init();
+ arc_init();
+ l2arc_init();
+}
+
+void
+dmu_fini(void)
+{
+ arc_fini();
+ dnode_fini();
+ dbuf_fini();
+ l2arc_fini();
+}