diff options
Diffstat (limited to 'module/zfs/dmu.c')
-rw-r--r-- | module/zfs/dmu.c | 1227 |
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(); +} |