C++ dsl_dataset_rele函数代码示例

static int
zcp_clones_iter(lua_State *state)
{
	int err;
	char clonename[ZFS_MAX_DATASET_NAME_LEN];
	uint64_t dsobj = lua_tonumber(state, lua_upvalueindex(1));
	uint64_t cursor = lua_tonumber(state, lua_upvalueindex(2));
	dsl_pool_t *dp = zcp_run_info(state)->zri_pool;
	dsl_dataset_t *ds, *clone;
	zap_attribute_t za;
	zap_cursor_t zc;

	err = dsl_dataset_hold_obj(dp, dsobj, FTAG, &ds);
	if (err == ENOENT) {
		return (0);
	} else if (err != 0) {
		return (luaL_error(state,
		    "unexpected error %d from dsl_dataset_hold_obj(dsobj)",
		    err));
	}

	if (dsl_dataset_phys(ds)->ds_next_clones_obj == 0) {
		dsl_dataset_rele(ds, FTAG);
		return (0);
	}

	zap_cursor_init_serialized(&zc, dp->dp_meta_objset,
	    dsl_dataset_phys(ds)->ds_next_clones_obj, cursor);
	dsl_dataset_rele(ds, FTAG);

	err = zap_cursor_retrieve(&zc, &za);
	if (err != 0) {
		zap_cursor_fini(&zc);
		if (err != ENOENT) {
			return (luaL_error(state,
			    "unexpected error %d from zap_cursor_retrieve()",
			    err));
		}
		return (0);
	}
	zap_cursor_advance(&zc);
	cursor = zap_cursor_serialize(&zc);
	zap_cursor_fini(&zc);

	err = dsl_dataset_hold_obj(dp, za.za_first_integer, FTAG, &clone);
	if (err != 0) {
		return (luaL_error(state,
		    "unexpected error %d from "
		    "dsl_dataset_hold_obj(za_first_integer)", err));
	}

	dsl_dir_name(clone->ds_dir, clonename);
	dsl_dataset_rele(clone, FTAG);

	lua_pushnumber(state, cursor);
	lua_replace(state, lua_upvalueindex(2));

	(void) lua_pushstring(state, clonename);
	return (1);
}

static int
dsl_bookmark_create_check_impl(dsl_dataset_t *snapds, const char *bookmark_name,
    dmu_tx_t *tx)
{
	dsl_pool_t *dp = dmu_tx_pool(tx);
	dsl_dataset_t *bmark_fs;
	char *shortname;
	int error;
	zfs_bookmark_phys_t bmark_phys;

	if (!snapds->ds_is_snapshot)
		return (SET_ERROR(EINVAL));

	error = dsl_bookmark_hold_ds(dp, bookmark_name,
	    &bmark_fs, FTAG, &shortname);
	if (error != 0)
		return (error);

	if (!dsl_dataset_is_before(bmark_fs, snapds, 0)) {
		dsl_dataset_rele(bmark_fs, FTAG);
		return (SET_ERROR(EINVAL));
	}

	error = dsl_dataset_bmark_lookup(bmark_fs, shortname,
	    &bmark_phys);
	dsl_dataset_rele(bmark_fs, FTAG);
	if (error == 0)
		return (SET_ERROR(EEXIST));
	if (error == ESRCH)
		return (0);
	return (error);
}

static void
dsl_bookmark_create_sync(void *arg, dmu_tx_t *tx)
{
	dsl_bookmark_create_arg_t *dbca = arg;
	dsl_pool_t *dp = dmu_tx_pool(tx);
	objset_t *mos = dp->dp_meta_objset;
	nvpair_t *pair;

	ASSERT(spa_feature_is_enabled(dp->dp_spa, SPA_FEATURE_BOOKMARKS));

	for (pair = nvlist_next_nvpair(dbca->dbca_bmarks, NULL);
	    pair != NULL; pair = nvlist_next_nvpair(dbca->dbca_bmarks, pair)) {
		dsl_dataset_t *snapds, *bmark_fs;
		zfs_bookmark_phys_t bmark_phys;
		char *shortname;

		VERIFY0(dsl_dataset_hold(dp, fnvpair_value_string(pair),
		    FTAG, &snapds));
		VERIFY0(dsl_bookmark_hold_ds(dp, nvpair_name(pair),
		    &bmark_fs, FTAG, &shortname));
		if (bmark_fs->ds_bookmarks == 0) {
			bmark_fs->ds_bookmarks =
			    zap_create_norm(mos, U8_TEXTPREP_TOUPPER,
			    DMU_OTN_ZAP_METADATA, DMU_OT_NONE, 0, tx);
			spa_feature_incr(dp->dp_spa, SPA_FEATURE_BOOKMARKS, tx);

			dsl_dataset_zapify(bmark_fs, tx);
			VERIFY0(zap_add(mos, bmark_fs->ds_object,
			    DS_FIELD_BOOKMARK_NAMES,
			    sizeof (bmark_fs->ds_bookmarks), 1,
			    &bmark_fs->ds_bookmarks, tx));
		}

		bmark_phys.zbm_guid = dsl_dataset_phys(snapds)->ds_guid;
		bmark_phys.zbm_creation_txg =
		    dsl_dataset_phys(snapds)->ds_creation_txg;
		bmark_phys.zbm_creation_time =
		    dsl_dataset_phys(snapds)->ds_creation_time;

		VERIFY0(zap_add(mos, bmark_fs->ds_bookmarks,
		    shortname, sizeof (uint64_t),
		    sizeof (zfs_bookmark_phys_t) / sizeof (uint64_t),
		    &bmark_phys, tx));

		spa_history_log_internal_ds(bmark_fs, "bookmark", tx,
		    "name=%s creation_txg=%llu target_snap=%llu",
		    shortname,
		    (longlong_t)bmark_phys.zbm_creation_txg,
		    (longlong_t)snapds->ds_object);

		dsl_dataset_rele(bmark_fs, FTAG);
		dsl_dataset_rele(snapds, FTAG);
	}
}

/*ARGSUSED*/
static int
dmu_objset_clone_check(void *arg, dmu_tx_t *tx)
{
	dmu_objset_clone_arg_t *doca = arg;
	dsl_dir_t *pdd;
	const char *tail;
	int error;
	dsl_dataset_t *origin;
	dsl_pool_t *dp = dmu_tx_pool(tx);

	if (strchr(doca->doca_clone, '@') != NULL)
		return (SET_ERROR(EINVAL));

	error = dsl_dir_hold(dp, doca->doca_clone, FTAG, &pdd, &tail);
	if (error != 0)
		return (error);
	if (tail == NULL) {
		dsl_dir_rele(pdd, FTAG);
		return (SET_ERROR(EEXIST));
	}
	/* You can't clone across pools. */
	if (pdd->dd_pool != dp) {
		dsl_dir_rele(pdd, FTAG);
		return (SET_ERROR(EXDEV));
	}
	error = dsl_fs_ss_limit_check(pdd, 1, ZFS_PROP_FILESYSTEM_LIMIT, NULL,
	    doca->doca_cred);
	if (error != 0) {
		dsl_dir_rele(pdd, FTAG);
		return (SET_ERROR(EDQUOT));
	}
	dsl_dir_rele(pdd, FTAG);

	error = dsl_dataset_hold(dp, doca->doca_origin, FTAG, &origin);
	if (error != 0)
		return (error);

	/* You can't clone across pools. */
	if (origin->ds_dir->dd_pool != dp) {
		dsl_dataset_rele(origin, FTAG);
		return (SET_ERROR(EXDEV));
	}

	/* You can only clone snapshots, not the head datasets. */
	if (!dsl_dataset_is_snapshot(origin)) {
		dsl_dataset_rele(origin, FTAG);
		return (SET_ERROR(EINVAL));
	}
	dsl_dataset_rele(origin, FTAG);

	return (0);
}

static void
dsl_dataset_user_hold_sync(void *arg, dmu_tx_t *tx)
{
	dsl_dataset_user_hold_arg_t *dduha = arg;
	dsl_pool_t *dp = dmu_tx_pool(tx);
	nvlist_t *tmpholds;
	nvpair_t *pair;
	uint64_t now = gethrestime_sec();

	if (dduha->dduha_minor != 0)
		tmpholds = fnvlist_alloc();
	else
		tmpholds = NULL;
	for (pair = nvlist_next_nvpair(dduha->dduha_chkholds, NULL);
	    pair != NULL;
	    pair = nvlist_next_nvpair(dduha->dduha_chkholds, pair)) {
		dsl_dataset_t *ds;

		VERIFY0(dsl_dataset_hold(dp, nvpair_name(pair), FTAG, &ds));
		dsl_dataset_user_hold_sync_one_impl(tmpholds, ds,
		    fnvpair_value_string(pair), dduha->dduha_minor, now, tx);
		dsl_dataset_rele(ds, FTAG);
	}
	dsl_onexit_hold_cleanup(dp->dp_spa, tmpholds, dduha->dduha_minor);
}

static int
zcp_exists(lua_State *state)
{
	zcp_run_info_t *ri = zcp_run_info(state);
	dsl_pool_t *dp = ri->zri_pool;
	zcp_lib_info_t *libinfo = &zcp_exists_info;

	zcp_parse_args(state, libinfo->name, libinfo->pargs, libinfo->kwargs);

	const char *dsname = lua_tostring(state, 1);

	dsl_dataset_t *ds;
	int error = dsl_dataset_hold(dp, dsname, FTAG, &ds);
	if (error == 0) {
		dsl_dataset_rele(ds, FTAG);
		lua_pushboolean(state, B_TRUE);
	} else if (error == ENOENT) {
		lua_pushboolean(state, B_FALSE);
	} else if (error == EXDEV) {
		return (luaL_error(state, "dataset '%s' is not in the "
		    "target pool", dsname));
	} else if (error == EIO) {
		return (luaL_error(state, "I/O error opening dataset '%s'",
		    dsname));
	} else if (error != 0) {
		return (luaL_error(state, "unexpected error %d", error));
	}

	return (1);
}

int
dsl_destroy_snapshot_check(void *arg, dmu_tx_t *tx)
{
	dsl_destroy_snapshot_arg_t *ddsa = arg;
	const char *dsname = ddsa->ddsa_name;
	boolean_t defer = ddsa->ddsa_defer;

	dsl_pool_t *dp = dmu_tx_pool(tx);
	int error = 0;
	dsl_dataset_t *ds;

	error = dsl_dataset_hold(dp, dsname, FTAG, &ds);

	/*
	 * If the snapshot does not exist, silently ignore it, and
	 * dsl_destroy_snapshot_sync() will be a no-op
	 * (it's "already destroyed").
	 */
	if (error == ENOENT)
		return (0);

	if (error == 0) {
		error = dsl_destroy_snapshot_check_impl(ds, defer);
		dsl_dataset_rele(ds, FTAG);
	}

	return (error);
}

void
dsl_dir_stats(dsl_dir_t *dd, nvlist_t *nv)
{
	mutex_enter(&dd->dd_lock);
	dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USED, dd->dd_used_bytes);
	dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_QUOTA, dd->dd_phys->dd_quota);
	dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_RESERVATION,
	    dd->dd_phys->dd_reserved);
	dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_COMPRESSRATIO,
	    dd->dd_phys->dd_compressed_bytes == 0 ? 100 :
	    (dd->dd_phys->dd_uncompressed_bytes * 100 /
	    dd->dd_phys->dd_compressed_bytes));
	mutex_exit(&dd->dd_lock);

	rw_enter(&dd->dd_pool->dp_config_rwlock, RW_READER);
	if (dsl_dir_is_clone(dd)) {
		dsl_dataset_t *ds;
		char buf[MAXNAMELEN];

		VERIFY(0 == dsl_dataset_hold_obj(dd->dd_pool,
		    dd->dd_phys->dd_origin_obj, FTAG, &ds));
		dsl_dataset_name(ds, buf);
		dsl_dataset_rele(ds, FTAG);
		dsl_prop_nvlist_add_string(nv, ZFS_PROP_ORIGIN, buf);
	}
	rw_exit(&dd->dd_pool->dp_config_rwlock);
}

int
dsl_pool_open(spa_t *spa, uint64_t txg, dsl_pool_t **dpp)
{
	int err;
	dsl_pool_t *dp = dsl_pool_open_impl(spa, txg);
	dsl_dir_t *dd;
	dsl_dataset_t *ds;
	uint64_t obj;

	rw_enter(&dp->dp_config_rwlock, RW_WRITER);
	err = dmu_objset_open_impl(spa, NULL, &dp->dp_meta_rootbp,
	    &dp->dp_meta_objset);
	if (err)
		goto out;

	err = zap_lookup(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT,
	    DMU_POOL_ROOT_DATASET, sizeof (uint64_t), 1,
	    &dp->dp_root_dir_obj);
	if (err)
		goto out;

	err = dsl_dir_open_obj(dp, dp->dp_root_dir_obj,
	    NULL, dp, &dp->dp_root_dir);
	if (err)
		goto out;

	err = dsl_pool_open_special_dir(dp, MOS_DIR_NAME, &dp->dp_mos_dir);
	if (err)
		goto out;

	if (spa_version(spa) >= SPA_VERSION_ORIGIN) {
		err = dsl_pool_open_special_dir(dp, ORIGIN_DIR_NAME, &dd);
		if (err)
			goto out;
		err = dsl_dataset_hold_obj(dp, dd->dd_phys->dd_head_dataset_obj,
		    FTAG, &ds);
		if (err == 0) {
			err = dsl_dataset_hold_obj(dp,
			    ds->ds_phys->ds_prev_snap_obj, dp,
			    &dp->dp_origin_snap);
			dsl_dataset_rele(ds, FTAG);
		}
		dsl_dir_close(dd, dp);
		if (err)
			goto out;
	}

	if (spa_version(spa) >= SPA_VERSION_DEADLISTS) {
		err = dsl_pool_open_special_dir(dp, FREE_DIR_NAME,
		    &dp->dp_free_dir);
		if (err)
			goto out;

		err = zap_lookup(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT,
		    DMU_POOL_FREE_BPOBJ, sizeof (uint64_t), 1, &obj);
		if (err)
			goto out;
		VERIFY3U(0, ==, bpobj_open(&dp->dp_free_bpobj,
		    dp->dp_meta_objset, obj));
	}

static void
dmu_objset_create_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx)
{
	dsl_dir_t *dd = arg1;
	struct oscarg *oa = arg2;
	dsl_dataset_t *ds;
	blkptr_t *bp;
	uint64_t dsobj;

	ASSERT(dmu_tx_is_syncing(tx));

	dsobj = dsl_dataset_create_sync(dd, oa->lastname,
	    oa->clone_parent, oa->flags, cr, tx);

	VERIFY(0 == dsl_dataset_hold_obj(dd->dd_pool, dsobj, FTAG, &ds));
	bp = dsl_dataset_get_blkptr(ds);
	if (BP_IS_HOLE(bp)) {
		objset_impl_t *osi;

		/* This is an empty dmu_objset; not a clone. */
		osi = dmu_objset_create_impl(dsl_dataset_get_spa(ds),
		    ds, bp, oa->type, tx);

		if (oa->userfunc)
			oa->userfunc(&osi->os, oa->userarg, cr, tx);
	}

	spa_history_internal_log(LOG_DS_CREATE, dd->dd_pool->dp_spa,
	    tx, cr, "dataset = %llu", dsobj);

	dsl_dataset_rele(ds, FTAG);
}

/*
 * Get a list of all visble properties and their values for a given dataset.
 * Returned on the stack as a Lua table.
 */
static int
zcp_system_props_list(lua_State *state)
{
	int error;
	char errbuf[128];
	const char *dataset_name;
	dsl_pool_t *dp = zcp_run_info(state)->zri_pool;
	zcp_list_info_t *libinfo = &zcp_system_props_list_info;
	zcp_parse_args(state, libinfo->name, libinfo->pargs, libinfo->kwargs);
	dataset_name = lua_tostring(state, 1);
	nvlist_t *nv = fnvlist_alloc();

	dsl_dataset_t *ds = zcp_dataset_hold(state, dp, dataset_name, FTAG);
	if (ds == NULL)
		return (1); /* not reached; zcp_dataset_hold() longjmp'd */

	/* Get the names of all valid properties for this dataset */
	zcp_dataset_props(ds, nv);
	dsl_dataset_rele(ds, FTAG);

	/* push list as lua table */
	error = zcp_nvlist_to_lua(state, nv, errbuf, sizeof (errbuf));
	nvlist_free(nv);
	if (error != 0) {
		return (luaL_error(state,
		    "Error returning nvlist: %s", errbuf));
	}
	return (1);
}

static int
zcp_props_list(lua_State *state)
{
	const char *dsname = lua_tostring(state, 1);
	dsl_pool_t *dp = zcp_run_info(state)->zri_pool;
	objset_t *os;
	nvlist_t **props = lua_newuserdata(state, sizeof (nvlist_t *));

	dsl_dataset_t *ds = zcp_dataset_hold(state, dp, dsname, FTAG);
	if (ds == NULL)
		return (1); /* not reached; zcp_dataset_hold() longjmp'd */
	VERIFY0(dmu_objset_from_ds(ds, &os));
	VERIFY0(dsl_prop_get_all(os, props));
	dsl_dataset_rele(ds, FTAG);

	/*
	 * Set the metatable for the properties list to free it on completion.
	 */
	luaL_getmetatable(state, zcp_props_list_info.name);
	(void) lua_setmetatable(state, -2);

	lua_pushlightuserdata(state, NULL);
	lua_pushcclosure(state, &zcp_props_iter, 2);
	return (1);
}

static int
zcp_children_list(lua_State *state)
{
	const char *fsname = lua_tostring(state, 1);
	dsl_pool_t *dp = zcp_run_info(state)->zri_pool;
	boolean_t issnap;
	uint64_t dsobj;

	dsl_dataset_t *ds = zcp_dataset_hold(state, dp, fsname, FTAG);
	if (ds == NULL)
		return (1); /* not reached; zcp_dataset_hold() longjmp'd */

	issnap = ds->ds_is_snapshot;
	dsobj = ds->ds_object;
	dsl_dataset_rele(ds, FTAG);

	if (issnap) {
		return (zcp_argerror(state, 1,
		    "argument %s cannot be a snapshot", fsname));
	}

	lua_pushnumber(state, dsobj);
	lua_pushnumber(state, 0);
	lua_pushcclosure(state, &zcp_children_iter, 2);
	return (1);
}

static int
zcp_clones_list(lua_State *state)
{
	const char *snapname = lua_tostring(state, 1);
	dsl_pool_t *dp = zcp_run_info(state)->zri_pool;
	boolean_t issnap;
	uint64_t dsobj, cursor;

	/*
	 * zcp_dataset_hold will either successfully return the requested
	 * dataset or throw a lua error and longjmp out of the zfs.list.clones
	 * call without returning.
	 */
	dsl_dataset_t *ds = zcp_dataset_hold(state, dp, snapname, FTAG);
	if (ds == NULL)
		return (1); /* not reached; zcp_dataset_hold() longjmp'd */
	cursor = 0;
	issnap = ds->ds_is_snapshot;
	dsobj = ds->ds_object;
	dsl_dataset_rele(ds, FTAG);

	if (!issnap) {
		return (zcp_argerror(state, 1, "%s is not a snapshot",
		    snapname));
	}

	lua_pushnumber(state, dsobj);
	lua_pushnumber(state, cursor);
	lua_pushcclosure(state, &zcp_clones_iter, 2);
	return (1);
}

/* ARGSUSED */
int
dmu_objset_prefetch(char *name, void *arg)
{
	dsl_dataset_t *ds;

	if (dsl_dataset_hold(name, FTAG, &ds))
		return (0);

	if (!BP_IS_HOLE(&ds->ds_phys->ds_bp)) {
		mutex_enter(&ds->ds_opening_lock);
		if (!dsl_dataset_get_user_ptr(ds)) {
			uint32_t aflags = ARC_NOWAIT | ARC_PREFETCH;
			zbookmark_t zb;

			zb.zb_objset = ds->ds_object;
			zb.zb_object = 0;
			zb.zb_level = -1;
			zb.zb_blkid = 0;

			(void) arc_read_nolock(NULL, dsl_dataset_get_spa(ds),
			    &ds->ds_phys->ds_bp, NULL, NULL,
			    ZIO_PRIORITY_ASYNC_READ,
			    ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE,
			    &aflags, &zb);
		}
		mutex_exit(&ds->ds_opening_lock);
	}

	dsl_dataset_rele(ds, FTAG);
	return (0);
}