1 /* $NetBSD: subr_disk_open.c,v 1.14 2019/02/20 10:02:51 hannken 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 1.14 2019/02/20 10:02:51 hannken 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 vn_lock(tmpvn, LK_EXCLUSIVE | LK_RETRY); 69 error = VOP_OPEN(tmpvn, FREAD | FSILENT, NOCRED); 70 if (error) { 71 /* 72 * Ignore errors caused by missing device, partition, 73 * medium, or busy [presumably because of a wedge covering it] 74 */ 75 switch (error) { 76 case ENXIO: 77 case ENODEV: 78 case EBUSY: 79 break; 80 default: 81 printf("%s: can't open dev %s (%d)\n", 82 __func__, device_xname(dv), error); 83 break; 84 } 85 vput(tmpvn); 86 return NULL; 87 } 88 89 return tmpvn; 90 } 91 92 int 93 getdisksize(struct vnode *vp, uint64_t *numsecp, unsigned int *secsizep) 94 { 95 struct partinfo pi; 96 struct dkwedge_info dkw; 97 struct disk *pdk; 98 unsigned int secsize; 99 uint64_t numsec; 100 int error; 101 102 /* 103 * We attempt to get the wedge information first if it exists, 104 * because the label does not support larger size disks. 105 */ 106 error = VOP_IOCTL(vp, DIOCGWEDGEINFO, &dkw, FREAD, NOCRED); 107 if (error == 0) { 108 pdk = disk_find(dkw.dkw_parent); 109 if (pdk != NULL) { 110 secsize = DEV_BSIZE << pdk->dk_blkshift; 111 numsec = dkw.dkw_size; 112 } else 113 error = ENODEV; 114 } 115 116 if (error) { 117 error = VOP_IOCTL(vp, DIOCGPARTINFO, &pi, FREAD, NOCRED); 118 if (error == 0) { 119 secsize = pi.pi_secsize; 120 numsec = pi.pi_size; 121 } 122 } 123 124 if (error == 0 && 125 (secsize == 0 || secsize > MAXBSIZE || !powerof2(secsize) || 126 numsec == 0)) { 127 #ifdef DIAGNOSTIC 128 printf("%s: %s returns invalid disksize values" 129 " (secsize = %u, numsec = %" PRIu64 ")\n", 130 __func__, 131 devsw_blk2name(major(vp->v_specnode->sn_rdev)), 132 secsize, numsec); 133 #endif 134 error = EINVAL; 135 } 136 if (error == 0) { 137 *secsizep = secsize; 138 *numsecp = numsec; 139 } 140 141 return error; 142 } 143 144 int 145 getdiskinfo(struct vnode *vp, struct dkwedge_info *dkw) 146 { 147 struct partinfo pi; 148 int error; 149 dev_t dev = vp->v_specnode->sn_rdev; 150 151 if (VOP_IOCTL(vp, DIOCGWEDGEINFO, dkw, FREAD, NOCRED) == 0) 152 return 0; 153 154 if ((error = VOP_IOCTL(vp, DIOCGPARTINFO, &pi, FREAD, NOCRED)) != 0) 155 return error; 156 157 snprintf(dkw->dkw_devname, sizeof(dkw->dkw_devname), "%s%" PRId32 "%c", 158 devsw_blk2name(major(dev)), DISKUNIT(dev), (char)DISKPART(dev) + 159 'a'); 160 161 dkw->dkw_wname[0] = '\0'; 162 163 strlcpy(dkw->dkw_parent, dkw->dkw_devname, sizeof(dkw->dkw_parent)); 164 165 dkw->dkw_size = pi.pi_size; 166 dkw->dkw_offset = pi.pi_offset; 167 strlcpy(dkw->dkw_ptype, getfstypename(pi.pi_fstype), 168 sizeof(dkw->dkw_ptype)); 169 170 return 0; 171 } 172