sys/kern/subr_disk_open.c

   1 /*      $NetBSD$        */
   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, "$NetBSD$");
  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 }