xref: /openbmc/qemu/hw/s390x/s390-virtio-hcall.c (revision db76ec62)
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 "cpu.h"
13 #include "hw/s390x/s390-virtio.h"
14 
15 #define MAX_DIAG_SUBCODES 255
16 
17 static s390_virtio_fn s390_diag500_table[MAX_DIAG_SUBCODES];
18 
19 void s390_register_virtio_hypercall(uint64_t code, s390_virtio_fn fn)
20 {
21     assert(code < MAX_DIAG_SUBCODES);
22     assert(!s390_diag500_table[code]);
23 
24     s390_diag500_table[code] = fn;
25 }
26 
27 int s390_virtio_hypercall(CPUS390XState *env)
28 {
29     s390_virtio_fn fn;
30 
31     if (env->regs[1] < MAX_DIAG_SUBCODES) {
32         fn = s390_diag500_table[env->regs[1]];
33         if (fn) {
34             env->regs[2] = fn(&env->regs[2]);
35             return 0;
36         }
37     }
38 
39     return -EINVAL;
40 }
41