xref: /freebsd/sys/geom/label/g_label_disk_ident.c (revision 8d20be1e22095c27faf8fe8b2f0d089739cc742e)
1 /*-
2  * Copyright (c) 2012 Ivan Voras <ivoras@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 AUTHORS AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/kernel.h>
33 #include <sys/malloc.h>
34 
35 #include <geom/geom.h>
36 #include <geom/geom_disk.h>
37 #include <geom/label/g_label.h>
38 #include <geom/multipath/g_multipath.h>
39 
40 
41 #define G_LABEL_DISK_IDENT_DIR	"diskid"
42 
43 static char* classes_pass[] = { G_DISK_CLASS_NAME, G_MULTIPATH_CLASS_NAME,
44     NULL };
45 
46 static void
47 g_label_disk_ident_taste(struct g_consumer *cp, char *label, size_t size)
48 {
49 	struct g_class *cls;
50 	char ident[100];
51 	int ident_len, found, i;
52 
53 	g_topology_assert_not();
54 	label[0] = '\0';
55 
56 	cls = cp->provider->geom->class;
57 
58 	/*
59 	 * Get the GEOM::ident string, and construct a label in the format
60 	 * "CLASS_NAME-ident"
61 	 */
62 	ident_len = sizeof(ident);
63 	if (g_io_getattr("GEOM::ident", cp, &ident_len, ident) == 0) {
64 		if (ident_len == 0 || ident[0] == '\0')
65 			return;
66 		for (i = 0, found = 0; classes_pass[i] != NULL; i++)
67 			if (strcmp(classes_pass[i], cls->name) == 0) {
68 				found = 1;
69 				break;
70 			}
71 		if (!found)
72 			return;
73 		/*
74 		 * We can safely ignore the result of snprintf(): the label
75 		 * will simply be truncated, which at most is only annoying.
76 		 */
77 		(void)snprintf(label, size, "%s-%s", cls->name, ident);
78 	}
79 }
80 
81 struct g_label_desc g_label_disk_ident = {
82 	.ld_taste = g_label_disk_ident_taste,
83 	.ld_dir = G_LABEL_DISK_IDENT_DIR,
84 	.ld_enabled = 1
85 };
86 
87 G_LABEL_INIT(disk_ident, g_label_disk_ident, "Create device nodes for drives "
88     "which export a disk identification string");
89