1/* $NetBSD: subr_disk_open.c,v 1.13 2015/12/08 20:36:15 christos Exp $ */
2
3/*-
4 * Copyright (c) 2006 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 * POSSIBILITY OF SUCH DAMAGE.
27 */
28
29#include <sys/cdefs.h>
30__KERNEL_RCSID(0, "$NetBSD: subr_disk_open.c,v 1.13 2015/12/08 20:36:15 christos Exp $");
31
32#include <sys/param.h>
33#include <sys/conf.h>
34#include <sys/device.h>
35#include <sys/disk.h>
36#include <sys/disklabel.h>
37#include <sys/fcntl.h>
38#include <sys/kauth.h>
39#include <sys/vnode.h>
40#include <miscfs/specfs/specdev.h>
41
42struct vnode *
43opendisk(device_t dv)
44{
45 devmajor_t bmajor;
46 int unit;
47 struct vnode *tmpvn;
48 int error;
49 dev_t dev;
50
51 /*
52 * Lookup major number for disk block device.
53 */
54 bmajor = devsw_name2blk(device_xname(dv), NULL, 0);
55 if (bmajor == -1)
56 return NULL;
57
58 unit = device_unit(dv);
59 /*
60 * Fake a temporary vnode for the disk, open it, and read
61 * and hash the sectors.
62 */
63 dev = device_is_a(dv, "dk") ? makedev(bmajor, unit) :
64 MAKEDISKDEV(bmajor, unit, RAW_PART);
65 if (bdevvp(dev, &tmpvn))
66 panic("%s: can't alloc vnode for %s", __func__,
67 device_xname(dv));
68 error = VOP_OPEN(tmpvn, FREAD | FSILENT, NOCRED);
69 if (error) {
70 /*
71 * Ignore errors caused by missing device, partition,
72 * medium, or busy [presumably because of a wedge covering it]
73 */
74 switch (error) {
75 case ENXIO:
76 case ENODEV:
77 case EBUSY:
78 break;
79 default:
80 printf("%s: can't open dev %s (%d)\n",
81 __func__, device_xname(dv), error);
82 break;
83 }
84 vput(tmpvn);
85 return NULL;
86 }
87
88 return tmpvn;
89}
90
91int
92getdisksize(struct vnode *vp, uint64_t *numsecp, unsigned int *secsizep)
93{
94 struct partinfo pi;
95 struct dkwedge_info dkw;
96 struct disk *pdk;
97 unsigned int secsize;
98 uint64_t numsec;
99 int error;
100
101 /*
102 * We attempt to get the wedge information first if it exists,
103 * because the label does not support larger size disks.
104 */
105 error = VOP_IOCTL(vp, DIOCGWEDGEINFO, &dkw, FREAD, NOCRED);
106 if (error == 0) {
107 pdk = disk_find(dkw.dkw_parent);
108 if (pdk != NULL) {
109 secsize = DEV_BSIZE << pdk->dk_blkshift;
110 numsec = dkw.dkw_size;
111 } else
112 error = ENODEV;
113 }
114
115 if (error) {
116 error = VOP_IOCTL(vp, DIOCGPARTINFO, &pi, FREAD, NOCRED);
117 if (error == 0) {
118 secsize = pi.pi_secsize;
119 numsec = pi.pi_size;
120 }
121 }
122
123 if (error == 0 &&
124 (secsize == 0 || secsize > MAXBSIZE || !powerof2(secsize) ||
125 numsec == 0)) {
126#ifdef DIAGNOSTIC
127 printf("%s: %s returns invalid disksize values"
128 " (secsize = %u, numsec = %" PRIu64 ")\n",
129 __func__,
130 devsw_blk2name(major(vp->v_specnode->sn_rdev)),
131 secsize, numsec);
132#endif
133 error = EINVAL;
134 }
135 if (error == 0) {
136 *secsizep = secsize;
137 *numsecp = numsec;
138 }
139
140 return error;
141}
142
143int
144getdiskinfo(struct vnode *vp, struct dkwedge_info *dkw)
145{
146 struct partinfo pi;
147 int error;
148 dev_t dev = vp->v_specnode->sn_rdev;
149
150 if (VOP_IOCTL(vp, DIOCGWEDGEINFO, dkw, FREAD, NOCRED) == 0)
151 return 0;
152
153 if ((error = VOP_IOCTL(vp, DIOCGPARTINFO, &pi, FREAD, NOCRED)) != 0)
154 return error;
155
156 snprintf(dkw->dkw_devname, sizeof(dkw->dkw_devname), "%s%" PRId32 "%c",
157 devsw_blk2name(major(dev)), DISKUNIT(dev), (char)DISKPART(dev) +
158 'a');
159
160 dkw->dkw_wname[0] = '\0';
161
162 strlcpy(dkw->dkw_parent, dkw->dkw_devname, sizeof(dkw->dkw_parent));
163
164 dkw->dkw_size = pi.pi_size;
165 dkw->dkw_offset = pi.pi_offset;
166 strlcpy(dkw->dkw_ptype, getfstypename(pi.pi_fstype),
167 sizeof(dkw->dkw_ptype));
168
169 return 0;
170}
171