sys/dev/ata/ata_raid_subr.c

   1 /* $NetBSD$ */
   2
   3 /*-
   4  * Copyright (c) 2008 Juan Romero Pardines.
   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 AUTHOR ``AS IS'' AND ANY EXPRESS OR
  17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26  */
  27
  28 #include <sys/cdefs.h>
  29 __KERNEL_RCSID(0, "$NetBSD$");
  30
  31 #include <sys/param.h>
  32 #include <sys/systm.h>
  33 #include <sys/conf.h>
  34 #include <sys/kernel.h>
  35 #include <sys/dkio.h>
  36 #include <sys/disk.h>
  37 #include <sys/disklabel.h>
  38 #include <sys/fcntl.h>
  39 #include <sys/vnode.h>
  40 #include <sys/kauth.h>
  41 #include <sys/kmem.h>
  42
  43 #include <dev/ata/ata_raidvar.h>
  44
  45 struct ataraid_disk_vnode {
  46         struct ataraid_disk_info *adv_adi;
  47         struct vnode *adv_vnode;
  48         SLIST_ENTRY(ataraid_disk_vnode) adv_next;
  49 };
  50
  51 static SLIST_HEAD(, ataraid_disk_vnode) ataraid_disk_vnode_list =
  52     SLIST_HEAD_INITIALIZER(ataraid_disk_vnode_list);
  53
  54 /*
  55  * Finds the RAW_PART vnode of the block device associated with a component
  56  * by looking at the singly linked list; otherwise creates, opens and
  57  * returns the vnode to the caller.
  58  */
  59 struct vnode *
  60 ata_raid_disk_vnode_find(struct ataraid_disk_info *adi)
  61 {
  62         struct ataraid_disk_vnode *adv = NULL;
  63         struct vnode *vp = NULL;
  64         device_t devlist;
  65         int bmajor, error = 0;
  66         dev_t dev;
  67
  68         SLIST_FOREACH(adv, &ataraid_disk_vnode_list, adv_next) {
  69                 devlist = adv->adv_adi->adi_dev;
  70                 if (strcmp(device_xname(devlist),
  71                     device_xname(adi->adi_dev)) == 0)
  72                         return adv->adv_vnode;
  73         }
  74
  75         adv = NULL;
  76         adv = kmem_zalloc(sizeof(struct ataraid_disk_vnode), KM_SLEEP);
  77
  78         bmajor = devsw_name2blk(device_xname(adi->adi_dev), NULL, 0);
  79         dev = MAKEDISKDEV(bmajor, device_unit(adi->adi_dev), RAW_PART);
  80
  81         error = bdevvp(dev, &vp);
  82         if (error) {
  83                 kmem_free(adv, sizeof(struct ataraid_disk_vnode));
  84                 return NULL;
  85         }
  86         error = VOP_OPEN(vp, FREAD|FWRITE, NOCRED);
  87         if (error) {
  88                 vput(vp);
  89                 kmem_free(adv, sizeof(struct ataraid_disk_vnode));
  90                 return NULL;
  91         }
  92         vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
  93         VOP_UNLOCK(vp, 0);
  94
  95         adv->adv_adi = adi;
  96         adv->adv_vnode = vp;
  97
  98         SLIST_INSERT_HEAD(&ataraid_disk_vnode_list, adv, adv_next);
  99
 100         return adv->adv_vnode;
 101 }