hw/s390x/s390-virtio-hcall.c

   1 /*
   2  * Support for virtio hypercalls on s390
   3  *
   4  * Copyright 2012 IBM Corp.
   5  * Author(s): Cornelia Huck <cornelia.huck@de.ibm.com>
   6  *
   7  * This work is licensed under the terms of the GNU GPL, version 2 or (at
   8  * your option) any later version. See the COPYING file in the top-level
   9  * directory.
  10  */
  11
  12 #include "qemu/osdep.h"
  13 #include "cpu.h"
  14 #include "hw/s390x/s390-virtio.h"
  15
  16 #define MAX_DIAG_SUBCODES 255
  17
  18 static s390_virtio_fn s390_diag500_table[MAX_DIAG_SUBCODES];
  19
  20 void s390_register_virtio_hypercall(uint64_t code, s390_virtio_fn fn)
  21 {
  22     assert(code < MAX_DIAG_SUBCODES);
  23     assert(!s390_diag500_table[code]);
  24
  25     s390_diag500_table[code] = fn;
  26 }
  27
  28 int s390_virtio_hypercall(CPUS390XState *env)
  29 {
  30     s390_virtio_fn fn;
  31
  32     if (env->regs[1] < MAX_DIAG_SUBCODES) {
  33         fn = s390_diag500_table[env->regs[1]];
  34         if (fn) {
  35             env->regs[2] = fn(&env->regs[2]);
  36             return 0;
  37         }
  38     }
  39
  40     return -EINVAL;
  41 }