Support setting user properties in a channel program

This adds support for setting user properties in a
zfs channel program by adding 'zfs.sync.set_prop'
and 'zfs.check.set_prop' to the ZFS LUA API.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matt Ahrens <matt@delphix.com>
Co-authored-by: Sara Hartse <sara.hartse@delphix.com>
Contributions-by: Jason King <jason.king@joyent.com>
Signed-off-by: Sara Hartse <sara.hartse@delphix.com>
Signed-off-by: Jason King <jason.king@joyent.com>
Closes #9950

module/zfs/Makefile.in

@@ -105,6 +105,7 @@ $(MODULE)-objs += zcp.o
 $(MODULE)-objs += zcp_get.o
 $(MODULE)-objs += zcp_global.o
 $(MODULE)-objs += zcp_iter.o
+$(MODULE)-objs += zcp_set.o
 $(MODULE)-objs += zcp_synctask.o
 $(MODULE)-objs += zfeature.o
 $(MODULE)-objs += zfs_byteswap.o

module/zfs/zcp_set.c

@@ -0,0 +1,100 @@
+/*
+ * CDDL HEADER START
+ *
+ * This file and its contents are supplied under the terms of the
+ * Common Development and Distribution License ("CDDL"), version 1.0.
+ * You may only use this file in accordance with the terms of version
+ * 1.0 of the CDDL.
+ *
+ * A full copy of the text of the CDDL should have accompanied this
+ * source.  A copy of the CDDL is also available via the Internet at
+ * http://www.illumos.org/license/CDDL.
+ *
+ * CDDL HEADER END
+ */
+
+/*
+ * Copyright (c) 2016 by Delphix. All rights reserved.
+ * Copyrigh 2020 Joyent, Inc.
+ */
+
+#include <sys/lua/lua.h>
+#include <sys/lua/lualib.h>
+#include <sys/lua/lauxlib.h>
+
+#include <sys/dsl_prop.h>
+#include <sys/dsl_dir.h>
+#include <sys/dsl_synctask.h>
+#include <sys/dsl_dataset.h>
+#include <sys/zcp.h>
+#include <sys/zcp_set.h>
+#include <sys/zcp_iter.h>
+#include <sys/zcp_global.h>
+#include <sys/zvol.h>
+
+#include <zfs_prop.h>
+
+static void
+zcp_set_user_prop(lua_State *state, dsl_pool_t *dp, const char *dsname,
+    const char *prop_name, const char *prop_val, dmu_tx_t *tx)
+{
+	dsl_dataset_t *ds = zcp_dataset_hold(state, dp, dsname, FTAG);
+	if (ds == NULL)
+		return; /* not reached; zcp_dataset_hold() longjmp'd */
+
+	nvlist_t *nvl = fnvlist_alloc();
+	fnvlist_add_string(nvl, prop_name, prop_val);
+
+	dsl_props_set_sync_impl(ds, ZPROP_SRC_LOCAL, nvl, tx);
+
+	fnvlist_free(nvl);
+	dsl_dataset_rele(ds, FTAG);
+}
+
+int
+zcp_set_prop_check(void *arg, dmu_tx_t *tx)
+{
+	zcp_set_prop_arg_t *args = arg;
+	const char *prop_name = args->prop;
+	dsl_props_set_arg_t dpsa = {
+		.dpsa_dsname = args->dsname,
+		.dpsa_source = ZPROP_SRC_LOCAL,
+	};
+	nvlist_t *nvl = NULL;
+	int ret = 0;
+
+	/*
+	 * Only user properties are currently supported. When non-user
+	 * properties are supported, we will want to use
+	 * zfs_valid_proplist() to verify the properties.
+	 */
+	if (!zfs_prop_user(prop_name)) {
+		return (EINVAL);
+	}
+
+	nvl = fnvlist_alloc();
+	fnvlist_add_string(nvl, args->prop, args->val);
+	dpsa.dpsa_props = nvl;
+
+	ret = dsl_props_set_check(&dpsa, tx);
+	nvlist_free(nvl);
+
+	return (ret);
+}
+
+void
+zcp_set_prop_sync(void *arg, dmu_tx_t *tx)
+{
+	zcp_set_prop_arg_t *args = arg;
+	zcp_run_info_t *ri = zcp_run_info(args->state);
+	dsl_pool_t *dp = ri->zri_pool;
+
+	const char *dsname = args->dsname;
+	const char *prop_name = args->prop;
+	const char *prop_val = args->val;
+
+	if (zfs_prop_user(prop_name)) {
+		zcp_set_user_prop(args->state, dp, dsname, prop_name,
+		    prop_val, tx);
+	}
+}

module/zfs/zcp_synctask.c

@@ -23,6 +23,7 @@
 #include <sys/lua/lauxlib.h>
 
 #include <sys/zcp.h>
+#include <sys/zcp_set.h>
 #include <sys/dsl_dir.h>
 #include <sys/dsl_pool.h>
 #include <sys/dsl_prop.h>
@@ -414,6 +415,44 @@ zcp_synctask_bookmark(lua_State *state, boolean_t sync, nvlist_t *err_details)
 	return (err);
 }
 
+static int zcp_synctask_set_prop(lua_State *, boolean_t, nvlist_t *err_details);
+static zcp_synctask_info_t zcp_synctask_set_prop_info = {
+	.name = "set_prop",
+	.func = zcp_synctask_set_prop,
+	.space_check = ZFS_SPACE_CHECK_RESERVED,
+	.blocks_modified = 2,
+	.pargs = {
+		{ .za_name = "dataset", .za_lua_type = LUA_TSTRING},
+		{ .za_name = "property", .za_lua_type =  LUA_TSTRING},
+		{ .za_name = "value", .za_lua_type =  LUA_TSTRING},
+		{ NULL, 0 }
+	},
+	.kwargs = {
+		{ NULL, 0 }
+	}
+};
+
+static int
+zcp_synctask_set_prop(lua_State *state, boolean_t sync, nvlist_t *err_details)
+{
+	int err;
+	zcp_set_prop_arg_t args = { 0 };
+
+	const char *dsname = lua_tostring(state, 1);
+	const char *prop = lua_tostring(state, 2);
+	const char *val = lua_tostring(state, 3);
+
+	args.state = state;
+	args.dsname = dsname;
+	args.prop = prop;
+	args.val = val;
+
+	err = zcp_sync_task(state, zcp_set_prop_check, zcp_set_prop_sync,
+	    &args, sync, dsname);
+
+	return (err);
+}
+
 static int
 zcp_synctask_wrapper(lua_State *state)
 {
@@ -484,6 +523,7 @@ zcp_load_synctask_lib(lua_State *state, boolean_t sync)
 		&zcp_synctask_snapshot_info,
 		&zcp_synctask_inherit_prop_info,
 		&zcp_synctask_bookmark_info,
+		&zcp_synctask_set_prop_info,
 		NULL
 	};