xref: /netbsd-src/sys/kern/subr_disk_open.c (revision 62a8debe1dc62962e18a1c918def78666141273b)
1 /*	$NetBSD: subr_disk_open.c,v 1.2 2010/01/30 11:57:17 mlelstv 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 1.2 2010/01/30 11:57:17 mlelstv 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 
41 struct vnode *
42 opendisk(struct device *dv)
43 {
44 	int bmajor, bminor;
45 	struct vnode *tmpvn;
46 	int error;
47 	dev_t dev;
48 
49 	/*
50 	 * Lookup major number for disk block device.
51 	 */
52 	bmajor = devsw_name2blk(device_xname(dv), NULL, 0);
53 	if (bmajor == -1)
54 		return NULL;
55 
56 	bminor = minor(device_unit(dv));
57 	/*
58 	 * Fake a temporary vnode for the disk, open it, and read
59 	 * and hash the sectors.
60 	 */
61 	dev = device_is_a(dv, "dk") ? makedev(bmajor, bminor) :
62 	    MAKEDISKDEV(bmajor, bminor, RAW_PART);
63 	if (bdevvp(dev, &tmpvn))
64 		panic("%s: can't alloc vnode for %s", __func__,
65 		    device_xname(dv));
66 	error = VOP_OPEN(tmpvn, FREAD, NOCRED);
67 	if (error) {
68 #ifndef DEBUG
69 		/*
70 		 * Ignore errors caused by missing device, partition,
71 		 * or medium.
72 		 */
73 		if (error != ENXIO && error != ENODEV)
74 #endif
75 			printf("%s: can't open dev %s (%d)\n",
76 			    __func__, device_xname(dv), error);
77 		vput(tmpvn);
78 		return NULL;
79 	}
80 
81 	return tmpvn;
82 }
83 
84 int
85 getdisksize(struct vnode *vp, uint64_t *numsecp, unsigned *secsizep)
86 {
87 	struct partinfo dpart;
88 	struct dkwedge_info dkw;
89 	struct disk *pdk;
90 	int error;
91 
92 	error = VOP_IOCTL(vp, DIOCGPART, &dpart, FREAD, NOCRED);
93 	if (error == 0) {
94 		*secsizep = dpart.disklab->d_secsize;
95 		*numsecp  = dpart.part->p_size;
96 		return 0;
97 	}
98 
99 	error = VOP_IOCTL(vp, DIOCGWEDGEINFO, &dkw, FREAD, NOCRED);
100 	if (error == 0) {
101 		pdk = disk_find(dkw.dkw_parent);
102 		if (pdk != NULL) {
103 			*secsizep = DEV_BSIZE << pdk->dk_blkshift;
104 			*numsecp  = dkw.dkw_size;
105 		} else
106 			error = ENODEV;
107 	}
108 
109 	return error;
110 }
111