xref: /openbmc/qemu/hw/s390x/s390-pci-kvm.c (revision 2df1eb27)
1 /*
2  * s390 zPCI KVM interfaces
3  *
4  * Copyright 2022 IBM Corp.
5  * Author(s): Matthew Rosato <mjrosato@linux.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 
14 #include <linux/kvm.h>
15 
16 #include "kvm/kvm_s390x.h"
17 #include "target/s390x/kvm/pv.h"
18 #include "hw/s390x/s390-pci-bus.h"
19 #include "hw/s390x/s390-pci-kvm.h"
20 #include "hw/s390x/s390-pci-inst.h"
21 #include "hw/s390x/s390-pci-vfio.h"
22 #include "cpu_models.h"
23 
24 bool s390_pci_kvm_interp_allowed(void)
25 {
26     return kvm_s390_get_zpci_op() && !s390_is_pv();
27 }
28 
29 int s390_pci_kvm_aif_enable(S390PCIBusDevice *pbdev, ZpciFib *fib, bool assist)
30 {
31     int rc;
32     struct kvm_s390_zpci_op args = {
33         .fh = pbdev->fh,
34         .op = KVM_S390_ZPCIOP_REG_AEN,
35         .u.reg_aen.ibv = fib->aibv,
36         .u.reg_aen.sb = fib->aisb,
37         .u.reg_aen.noi = FIB_DATA_NOI(fib->data),
38         .u.reg_aen.isc = FIB_DATA_ISC(fib->data),
39         .u.reg_aen.sbo = FIB_DATA_AISBO(fib->data),
40         .u.reg_aen.flags = (assist) ? 0 : KVM_S390_ZPCIOP_REGAEN_HOST
41     };
42 
43     if (pbdev->aif) {
44         return -EINVAL;
45     }
46 
47     rc = kvm_vm_ioctl(kvm_state, KVM_S390_ZPCI_OP, &args);
48     if (rc == 0) {
49         pbdev->aif = true;
50     }
51 
52     return rc;
53 }
54 
55 int s390_pci_kvm_aif_disable(S390PCIBusDevice *pbdev)
56 {
57     int rc;
58 
59     struct kvm_s390_zpci_op args = {
60         .fh = pbdev->fh,
61         .op = KVM_S390_ZPCIOP_DEREG_AEN
62     };
63 
64     if (!pbdev->aif) {
65         return -EINVAL;
66     }
67 
68     /*
69      * The device may have already been reset but we still want to relinquish
70      * the guest ISC, so always be sure to use an up-to-date host fh.
71      */
72     if (!s390_pci_get_host_fh(pbdev, &args.fh)) {
73         return -EPERM;
74     }
75 
76     rc = kvm_vm_ioctl(kvm_state, KVM_S390_ZPCI_OP, &args);
77     if (rc == 0) {
78         pbdev->aif = false;
79     }
80 
81     return rc;
82 }
83