cp/guest/attach.c

   1 /*
   2  * (C) Copyright 2007-2012  Josef 'Jeff' Sipek <jeffpc@josefsipek.net>
   3  *
   4  * This file is released under the GPLv2.  See the COPYING file for more
   5  * details.
   6  */
   7
   8 #include <circbuf.h>
   9 #include <vcpu.h>
  10 #include <guest.h>
  11 #include <sclp.h>
  12
  13 static void guest_append_crw(struct virt_sys *sys, struct crw *crw)
  14 {
  15         insert_circbuf(&sys->crws, crw);
  16 }
  17
  18 int guest_attach(struct virt_sys *sys, u64 rdev, u64 vdev)
  19 {
  20         struct directory_vdev dv = {
  21                 .type = VDEV_DED,
  22                 .vdev = vdev,
  23                 .u.dedicate.rdev = rdev,
  24         };
  25         struct virt_device *cur;
  26         struct crw crw;
  27         int found;
  28         int ret;
  29         u64 sch;
  30
  31         mutex_lock(&sys->virt_devs_lock);
  32
  33         /* are we supposed to pick a vdev number? */
  34         if (vdev == -1) {
  35                 /* TODO: this is a super-stupid algorithm - fix it */
  36                 for(vdev=0x0000; vdev<=0xffff; vdev++) {
  37                         found = 0;
  38                         list_for_each_entry(cur, &sys->virt_devs, devices) {
  39                                 if (cur->pmcw.dev_num == vdev) {
  40                                         found = 1;
  41                                         break;
  42                                 }
  43                         }
  44
  45                         if (!found)
  46                                 break;
  47                 }
  48
  49                 if (found)
  50                         goto out_err;
  51
  52                 dv.vdev = vdev;
  53         }
  54
  55         /* pick a subchannel number
  56          * TODO: this is a super-stupid algorithm - fix it
  57          */
  58         for(sch=0x10000; sch<=0x1ffff; sch++) {
  59                 found = 0;
  60                 list_for_each_entry(cur, &sys->virt_devs, devices) {
  61                         if (cur->sch == sch) {
  62                                 found = 1;
  63                                 break;
  64                         }
  65                 }
  66
  67                 if (!found)
  68                         break;
  69         }
  70
  71         if (found)
  72                 goto out_err;
  73
  74         memset(&crw, 0, sizeof(struct crw));
  75         crw.rsc = 0x3;
  76         crw.erc = 0x4;
  77         crw.id  = sch & ~0x10000;
  78
  79         /* add the device */
  80         ret = alloc_virt_dev(sys, &dv, sch);
  81
  82         if (!ret)
  83                 guest_append_crw(sys, &crw);
  84
  85         mutex_unlock(&sys->virt_devs_lock);
  86         return ret;
  87
  88 out_err:
  89         mutex_unlock(&sys->virt_devs_lock);
  90         return -EBUSY;
  91 }