xref: /openbmc/qemu/hw/ppc/pef.c (revision 4011a686)
1 /*
2  * PEF (Protected Execution Facility) for POWER support
3  *
4  * Copyright Red Hat.
5  *
6  * This work is licensed under the terms of the GNU GPL, version 2 or later.
7  * See the COPYING file in the top-level directory.
8  *
9  */
10 
11 #include "qemu/osdep.h"
12 
13 #include "qapi/error.h"
14 #include "qom/object_interfaces.h"
15 #include "sysemu/kvm.h"
16 #include "migration/blocker.h"
17 #include "exec/confidential-guest-support.h"
18 #include "hw/ppc/pef.h"
19 
20 #define TYPE_PEF_GUEST "pef-guest"
21 OBJECT_DECLARE_SIMPLE_TYPE(PefGuest, PEF_GUEST)
22 
23 typedef struct PefGuest PefGuest;
24 typedef struct PefGuestClass PefGuestClass;
25 
26 struct PefGuestClass {
27     ConfidentialGuestSupportClass parent_class;
28 };
29 
30 /**
31  * PefGuest:
32  *
33  * The PefGuest object is used for creating and managing a PEF
34  * guest.
35  *
36  * # $QEMU \
37  *         -object pef-guest,id=pef0 \
38  *         -machine ...,confidential-guest-support=pef0
39  */
40 struct PefGuest {
41     ConfidentialGuestSupport parent_obj;
42 };
43 
44 static int kvmppc_svm_init(Error **errp)
45 {
46 #ifdef CONFIG_KVM
47     static Error *pef_mig_blocker;
48 
49     if (!kvm_check_extension(kvm_state, KVM_CAP_PPC_SECURE_GUEST)) {
50         error_setg(errp,
51                    "KVM implementation does not support Secure VMs (is an ultravisor running?)");
52         return -1;
53     } else {
54         int ret = kvm_vm_enable_cap(kvm_state, KVM_CAP_PPC_SECURE_GUEST, 0, 1);
55 
56         if (ret < 0) {
57             error_setg(errp,
58                        "Error enabling PEF with KVM");
59             return -1;
60         }
61     }
62 
63     /* add migration blocker */
64     error_setg(&pef_mig_blocker, "PEF: Migration is not implemented");
65     /* NB: This can fail if --only-migratable is used */
66     migrate_add_blocker(pef_mig_blocker, &error_fatal);
67 
68     return 0;
69 #else
70     g_assert_not_reached();
71 #endif
72 }
73 
74 /*
75  * Don't set error if KVM_PPC_SVM_OFF ioctl is invoked on kernels
76  * that don't support this ioctl.
77  */
78 static int kvmppc_svm_off(Error **errp)
79 {
80 #ifdef CONFIG_KVM
81     int rc;
82 
83     rc = kvm_vm_ioctl(KVM_STATE(current_accel()), KVM_PPC_SVM_OFF);
84     if (rc && rc != -ENOTTY) {
85         error_setg_errno(errp, -rc, "KVM_PPC_SVM_OFF ioctl failed");
86         return rc;
87     }
88     return 0;
89 #else
90     g_assert_not_reached();
91 #endif
92 }
93 
94 int pef_kvm_init(ConfidentialGuestSupport *cgs, Error **errp)
95 {
96     if (!object_dynamic_cast(OBJECT(cgs), TYPE_PEF_GUEST)) {
97         return 0;
98     }
99 
100     if (!kvm_enabled()) {
101         error_setg(errp, "PEF requires KVM");
102         return -1;
103     }
104 
105     return kvmppc_svm_init(errp);
106 }
107 
108 int pef_kvm_reset(ConfidentialGuestSupport *cgs, Error **errp)
109 {
110     if (!object_dynamic_cast(OBJECT(cgs), TYPE_PEF_GUEST)) {
111         return 0;
112     }
113 
114     /*
115      * If we don't have KVM we should never have been able to
116      * initialize PEF, so we should never get this far
117      */
118     assert(kvm_enabled());
119 
120     return kvmppc_svm_off(errp);
121 }
122 
123 OBJECT_DEFINE_TYPE_WITH_INTERFACES(PefGuest,
124                                    pef_guest,
125                                    PEF_GUEST,
126                                    CONFIDENTIAL_GUEST_SUPPORT,
127                                    { TYPE_USER_CREATABLE },
128                                    { NULL })
129 
130 static void pef_guest_class_init(ObjectClass *oc, void *data)
131 {
132 }
133 
134 static void pef_guest_init(Object *obj)
135 {
136 }
137 
138 static void pef_guest_finalize(Object *obj)
139 {
140 }
141