xref: /qemu/hw/vfio/cpr.c (revision 563ac3d18129a2770a285cc16c20ad50c8adc7c0)
1 /*
2  * Copyright (c) 2021-2024 Oracle and/or its affiliates.
3  *
4  * This work is licensed under the terms of the GNU GPL, version 2 or later.
5  * See the COPYING file in the top-level directory.
6  */
7 
8 #include "qemu/osdep.h"
9 #include "hw/vfio/vfio-device.h"
10 #include "hw/vfio/vfio-cpr.h"
11 #include "hw/vfio/pci.h"
12 #include "hw/pci/msix.h"
13 #include "hw/pci/msi.h"
14 #include "migration/cpr.h"
15 #include "qapi/error.h"
16 #include "system/runstate.h"
17 
vfio_cpr_reboot_notifier(NotifierWithReturn * notifier,MigrationEvent * e,Error ** errp)18 int vfio_cpr_reboot_notifier(NotifierWithReturn *notifier,
19                              MigrationEvent *e, Error **errp)
20 {
21     if (e->type == MIG_EVENT_PRECOPY_SETUP &&
22         !runstate_check(RUN_STATE_SUSPENDED) && !vm_get_suspended()) {
23 
24         error_setg(errp,
25             "VFIO device only supports cpr-reboot for runstate suspended");
26 
27         return -1;
28     }
29     return 0;
30 }
31 
32 #define STRDUP_VECTOR_FD_NAME(vdev, name)   \
33     g_strdup_printf("%s_%s", (vdev)->vbasedev.name, (name))
34 
vfio_cpr_save_vector_fd(VFIOPCIDevice * vdev,const char * name,int nr,int fd)35 void vfio_cpr_save_vector_fd(VFIOPCIDevice *vdev, const char *name, int nr,
36                              int fd)
37 {
38     g_autofree char *fdname = STRDUP_VECTOR_FD_NAME(vdev, name);
39     cpr_save_fd(fdname, nr, fd);
40 }
41 
vfio_cpr_load_vector_fd(VFIOPCIDevice * vdev,const char * name,int nr)42 int vfio_cpr_load_vector_fd(VFIOPCIDevice *vdev, const char *name, int nr)
43 {
44     g_autofree char *fdname = STRDUP_VECTOR_FD_NAME(vdev, name);
45     return cpr_find_fd(fdname, nr);
46 }
47 
vfio_cpr_delete_vector_fd(VFIOPCIDevice * vdev,const char * name,int nr)48 void vfio_cpr_delete_vector_fd(VFIOPCIDevice *vdev, const char *name, int nr)
49 {
50     g_autofree char *fdname = STRDUP_VECTOR_FD_NAME(vdev, name);
51     cpr_delete_fd(fdname, nr);
52 }
53 
vfio_cpr_claim_vectors(VFIOPCIDevice * vdev,int nr_vectors,bool msix)54 static void vfio_cpr_claim_vectors(VFIOPCIDevice *vdev, int nr_vectors,
55                                    bool msix)
56 {
57     int i, fd;
58     bool pending = false;
59     PCIDevice *pdev = &vdev->pdev;
60 
61     vdev->nr_vectors = nr_vectors;
62     vdev->msi_vectors = g_new0(VFIOMSIVector, nr_vectors);
63     vdev->interrupt = msix ? VFIO_INT_MSIX : VFIO_INT_MSI;
64 
65     vfio_pci_prepare_kvm_msi_virq_batch(vdev);
66 
67     for (i = 0; i < nr_vectors; i++) {
68         VFIOMSIVector *vector = &vdev->msi_vectors[i];
69 
70         fd = vfio_cpr_load_vector_fd(vdev, "interrupt", i);
71         if (fd >= 0) {
72             vfio_pci_vector_init(vdev, i);
73             vfio_pci_msi_set_handler(vdev, i);
74         }
75 
76         if (vfio_cpr_load_vector_fd(vdev, "kvm_interrupt", i) >= 0) {
77             vfio_pci_add_kvm_msi_virq(vdev, vector, i, msix);
78         } else {
79             vdev->msi_vectors[i].virq = -1;
80         }
81 
82         if (msix && msix_is_pending(pdev, i) && msix_is_masked(pdev, i)) {
83             set_bit(i, vdev->msix->pending);
84             pending = true;
85         }
86     }
87 
88     vfio_pci_commit_kvm_msi_virq_batch(vdev);
89 
90     if (msix) {
91         memory_region_set_enabled(&pdev->msix_pba_mmio, pending);
92     }
93 }
94 
95 /*
96  * The kernel may change non-emulated config bits.  Exclude them from the
97  * changed-bits check in get_pci_config_device.
98  */
vfio_cpr_pci_pre_load(void * opaque)99 static int vfio_cpr_pci_pre_load(void *opaque)
100 {
101     VFIOPCIDevice *vdev = opaque;
102     PCIDevice *pdev = &vdev->pdev;
103     int size = MIN(pci_config_size(pdev), vdev->config_size);
104     int i;
105 
106     for (i = 0; i < size; i++) {
107         pdev->cmask[i] &= vdev->emulated_config_bits[i];
108     }
109 
110     return 0;
111 }
112 
vfio_cpr_pci_post_load(void * opaque,int version_id)113 static int vfio_cpr_pci_post_load(void *opaque, int version_id)
114 {
115     VFIOPCIDevice *vdev = opaque;
116     PCIDevice *pdev = &vdev->pdev;
117     int nr_vectors;
118 
119     if (msix_enabled(pdev)) {
120         vfio_pci_msix_set_notifiers(vdev);
121         nr_vectors = vdev->msix->entries;
122         vfio_cpr_claim_vectors(vdev, nr_vectors, true);
123 
124     } else if (msi_enabled(pdev)) {
125         nr_vectors = msi_nr_vectors_allocated(pdev);
126         vfio_cpr_claim_vectors(vdev, nr_vectors, false);
127 
128     } else if (vfio_pci_read_config(pdev, PCI_INTERRUPT_PIN, 1)) {
129         Error *local_err = NULL;
130         if (!vfio_pci_intx_enable(vdev, &local_err)) {
131             error_report_err(local_err);
132             return -1;
133         }
134     }
135 
136     return 0;
137 }
138 
pci_msix_present(void * opaque,int version_id)139 static bool pci_msix_present(void *opaque, int version_id)
140 {
141     PCIDevice *pdev = opaque;
142 
143     return msix_present(pdev);
144 }
145 
146 static const VMStateDescription vfio_intx_vmstate = {
147     .name = "vfio-cpr-intx",
148     .version_id = 0,
149     .minimum_version_id = 0,
150     .fields = (VMStateField[]) {
151         VMSTATE_BOOL(pending, VFIOINTx),
152         VMSTATE_UINT32(route.mode, VFIOINTx),
153         VMSTATE_INT32(route.irq, VFIOINTx),
154         VMSTATE_END_OF_LIST()
155     }
156 };
157 
158 #define VMSTATE_VFIO_INTX(_field, _state) {                         \
159     .name       = (stringify(_field)),                              \
160     .size       = sizeof(VFIOINTx),                                 \
161     .vmsd       = &vfio_intx_vmstate,                               \
162     .flags      = VMS_STRUCT,                                       \
163     .offset     = vmstate_offset_value(_state, _field, VFIOINTx),   \
164 }
165 
166 const VMStateDescription vfio_cpr_pci_vmstate = {
167     .name = "vfio-cpr-pci",
168     .version_id = 0,
169     .minimum_version_id = 0,
170     .pre_load = vfio_cpr_pci_pre_load,
171     .post_load = vfio_cpr_pci_post_load,
172     .needed = cpr_incoming_needed,
173     .fields = (VMStateField[]) {
174         VMSTATE_PCI_DEVICE(pdev, VFIOPCIDevice),
175         VMSTATE_MSIX_TEST(pdev, VFIOPCIDevice, pci_msix_present),
176         VMSTATE_VFIO_INTX(intx, VFIOPCIDevice),
177         VMSTATE_END_OF_LIST()
178     }
179 };
180 
181 static NotifierWithReturn kvm_close_notifier;
182 
vfio_cpr_kvm_close_notifier(NotifierWithReturn * notifier,MigrationEvent * e,Error ** errp)183 static int vfio_cpr_kvm_close_notifier(NotifierWithReturn *notifier,
184                                        MigrationEvent *e,
185                                        Error **errp)
186 {
187     if (e->type == MIG_EVENT_PRECOPY_DONE) {
188         vfio_kvm_device_close();
189     }
190     return 0;
191 }
192 
vfio_cpr_add_kvm_notifier(void)193 void vfio_cpr_add_kvm_notifier(void)
194 {
195     if (!kvm_close_notifier.notify) {
196         migration_add_notifier_mode(&kvm_close_notifier,
197                                     vfio_cpr_kvm_close_notifier,
198                                     MIG_MODE_CPR_TRANSFER);
199     }
200 }
201