xref: /freebsd/sbin/zfsbootcfg/zfsbootcfg.c (revision e17f5b1d)
1 /*-
2  * Copyright (c) 2016 Andriy Gapon <avg@FreeBSD.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24  */
25 
26 #include <sys/cdefs.h>
27 __FBSDID("$FreeBSD$");
28 
29 #include <sys/types.h>
30 #include <errno.h>
31 #include <limits.h>
32 #include <inttypes.h>
33 #include <stdio.h>
34 #include <stdlib.h>
35 #include <string.h>
36 #include <kenv.h>
37 
38 #include <libzfs.h>
39 
40 /* Keep in sync with zfsboot.c. */
41 #define MAX_COMMAND_LEN	512
42 
43 int
44 install_bootonce(libzfs_handle_t *hdl, uint64_t pool_guid, nvlist_t *nv,
45     const char * const data)
46 {
47 	nvlist_t **child;
48 	uint_t children = 0;
49 	uint64_t guid;
50 	int rv;
51 
52 	(void) nvlist_lookup_nvlist_array(nv, ZPOOL_CONFIG_CHILDREN, &child,
53 	    &children);
54 
55 	for (int c = 0; c < children; c++) {
56 		rv = install_bootonce(hdl, pool_guid, child[c], data);
57 	}
58 
59 	if (children > 0)
60 		return (rv);
61 
62 	if (nvlist_lookup_uint64(nv, ZPOOL_CONFIG_GUID, &guid) != 0) {
63 		perror("can't get vdev guid");
64 		return (1);
65 	}
66 	if (zpool_nextboot(hdl, pool_guid, guid, data) != 0) {
67 		perror("ZFS_IOC_NEXTBOOT failed");
68 		return (1);
69 	}
70 	return (0);
71 }
72 
73 int main(int argc, const char * const *argv)
74 {
75 	char buf[32], *name;
76 	libzfs_handle_t *hdl;
77 	zpool_handle_t *zphdl;
78 	uint64_t pool_guid;
79 	nvlist_t *nv, *config;
80 	int rv;
81 	int len;
82 
83 	if (argc != 2) {
84 		fprintf(stderr, "usage: zfsbootcfg <boot.config(5) options>\n");
85 		return (1);
86 	}
87 
88 	len = strlen(argv[1]);
89 	if (len >= MAX_COMMAND_LEN) {
90 		fprintf(stderr, "options string is too long\n");
91 		return (1);
92 	}
93 
94 	if (kenv(KENV_GET, "vfs.root.mountfrom", buf, sizeof(buf)) <= 0) {
95 		perror("can't get vfs.root.mountfrom");
96 		return (1);
97 	}
98 
99 	if (strncmp(buf, "zfs:", 4) == 0) {
100 		name = strchr(buf + 4, '/');
101 		if (name != NULL)
102 			*name = '\0';
103 		name = buf + 4;
104 	} else {
105 		perror("not a zfs root");
106 		return (1);
107 	}
108 
109 	if ((hdl = libzfs_init()) == NULL) {
110 		(void) fprintf(stderr, "internal error: failed to "
111 		    "initialize ZFS library\n");
112 		return (1);
113 	}
114 
115 	zphdl = zpool_open(hdl, name);
116 	if (zphdl == NULL) {
117 		perror("can't open pool");
118 		libzfs_fini(hdl);
119 		return (1);
120 	}
121 
122 	pool_guid = zpool_get_prop_int(zphdl, ZPOOL_PROP_GUID, NULL);
123 
124 	config = zpool_get_config(zphdl, NULL);
125 	if (config == NULL) {
126 		perror("can't get pool config");
127 		zpool_close(zphdl);
128 		libzfs_fini(hdl);
129 		return (1);
130 	}
131 
132 	if (nvlist_lookup_nvlist(config, ZPOOL_CONFIG_VDEV_TREE, &nv) != 0) {
133 		perror("failed to get vdev tree");
134 		zpool_close(zphdl);
135 		libzfs_fini(hdl);
136 		return (1);
137 	}
138 
139 	rv = install_bootonce(hdl, pool_guid, nv, argv[1]);
140 
141 	zpool_close(zphdl);
142 	libzfs_fini(hdl);
143 	if (rv == 0)
144 		printf("zfs next boot options are successfully written\n");
145 	return (rv);
146 }
147