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 42 struct vnode * 43 opendisk(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 91 int 92 getdisksize(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 } 142 143 int 144 getdiskinfo(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