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14#include "qemu/osdep.h"
15#include "hw/virtio/virtio-scsi.h"
16#include "qemu/error-report.h"
17#include "sysemu/block-backend.h"
18#include <hw/scsi/scsi.h>
19#include <block/scsi.h>
20#include <hw/virtio/virtio-bus.h>
21#include "hw/virtio/virtio-access.h"
22
23
24void virtio_scsi_set_iothread(VirtIOSCSI *s, IOThread *iothread)
25{
26 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(s)));
27 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
28 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s);
29
30 assert(!s->ctx);
31 s->ctx = iothread_get_aio_context(vs->conf.iothread);
32
33
34 if (!k->set_guest_notifiers || !k->set_host_notifier) {
35 fprintf(stderr, "virtio-scsi: Failed to set iothread "
36 "(transport does not support notifiers)");
37 exit(1);
38 }
39}
40
41static void virtio_scsi_data_plane_handle_cmd(VirtIODevice *vdev,
42 VirtQueue *vq)
43{
44 VirtIOSCSI *s = (VirtIOSCSI *)vdev;
45
46 assert(s->ctx && s->dataplane_started);
47 virtio_scsi_handle_cmd_vq(s, vq);
48}
49
50static void virtio_scsi_data_plane_handle_ctrl(VirtIODevice *vdev,
51 VirtQueue *vq)
52{
53 VirtIOSCSI *s = VIRTIO_SCSI(vdev);
54
55 assert(s->ctx && s->dataplane_started);
56 virtio_scsi_handle_ctrl_vq(s, vq);
57}
58
59static void virtio_scsi_data_plane_handle_event(VirtIODevice *vdev,
60 VirtQueue *vq)
61{
62 VirtIOSCSI *s = VIRTIO_SCSI(vdev);
63
64 assert(s->ctx && s->dataplane_started);
65 virtio_scsi_handle_event_vq(s, vq);
66}
67
68static int virtio_scsi_vring_init(VirtIOSCSI *s, VirtQueue *vq, int n,
69 void (*fn)(VirtIODevice *vdev, VirtQueue *vq))
70{
71 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(s)));
72 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
73 int rc;
74
75
76 rc = k->set_host_notifier(qbus->parent, n, true);
77 if (rc != 0) {
78 fprintf(stderr, "virtio-scsi: Failed to set host notifier (%d)\n",
79 rc);
80 s->dataplane_fenced = true;
81 return rc;
82 }
83
84 virtio_queue_aio_set_host_notifier_handler(vq, s->ctx, fn);
85 return 0;
86}
87
88void virtio_scsi_dataplane_notify(VirtIODevice *vdev, VirtIOSCSIReq *req)
89{
90 if (virtio_should_notify(vdev, req->vq)) {
91 event_notifier_set(virtio_queue_get_guest_notifier(req->vq));
92 }
93}
94
95
96static void virtio_scsi_clear_aio(VirtIOSCSI *s)
97{
98 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s);
99 int i;
100
101 virtio_queue_aio_set_host_notifier_handler(vs->ctrl_vq, s->ctx, NULL);
102 virtio_queue_aio_set_host_notifier_handler(vs->event_vq, s->ctx, NULL);
103 for (i = 0; i < vs->conf.num_queues; i++) {
104 virtio_queue_aio_set_host_notifier_handler(vs->cmd_vqs[i], s->ctx, NULL);
105 }
106}
107
108
109void virtio_scsi_dataplane_start(VirtIOSCSI *s)
110{
111 int i;
112 int rc;
113 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(s)));
114 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
115 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s);
116
117 if (s->dataplane_started ||
118 s->dataplane_starting ||
119 s->dataplane_fenced ||
120 s->ctx != iothread_get_aio_context(vs->conf.iothread)) {
121 return;
122 }
123
124 s->dataplane_starting = true;
125
126
127 rc = k->set_guest_notifiers(qbus->parent, vs->conf.num_queues + 2, true);
128 if (rc != 0) {
129 fprintf(stderr, "virtio-scsi: Failed to set guest notifiers (%d), "
130 "ensure -enable-kvm is set\n", rc);
131 goto fail_guest_notifiers;
132 }
133
134 aio_context_acquire(s->ctx);
135 rc = virtio_scsi_vring_init(s, vs->ctrl_vq, 0,
136 virtio_scsi_data_plane_handle_ctrl);
137 if (rc) {
138 goto fail_vrings;
139 }
140 rc = virtio_scsi_vring_init(s, vs->event_vq, 1,
141 virtio_scsi_data_plane_handle_event);
142 if (rc) {
143 goto fail_vrings;
144 }
145 for (i = 0; i < vs->conf.num_queues; i++) {
146 rc = virtio_scsi_vring_init(s, vs->cmd_vqs[i], i + 2,
147 virtio_scsi_data_plane_handle_cmd);
148 if (rc) {
149 goto fail_vrings;
150 }
151 }
152
153 s->dataplane_starting = false;
154 s->dataplane_started = true;
155 aio_context_release(s->ctx);
156 return;
157
158fail_vrings:
159 virtio_scsi_clear_aio(s);
160 aio_context_release(s->ctx);
161 for (i = 0; i < vs->conf.num_queues + 2; i++) {
162 k->set_host_notifier(qbus->parent, i, false);
163 }
164 k->set_guest_notifiers(qbus->parent, vs->conf.num_queues + 2, false);
165fail_guest_notifiers:
166 s->dataplane_fenced = true;
167 s->dataplane_starting = false;
168 s->dataplane_started = true;
169}
170
171
172void virtio_scsi_dataplane_stop(VirtIOSCSI *s)
173{
174 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(s)));
175 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
176 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s);
177 int i;
178
179 if (!s->dataplane_started || s->dataplane_stopping) {
180 return;
181 }
182
183
184 if (s->dataplane_fenced) {
185 s->dataplane_fenced = false;
186 s->dataplane_started = false;
187 return;
188 }
189 s->dataplane_stopping = true;
190 assert(s->ctx == iothread_get_aio_context(vs->conf.iothread));
191
192 aio_context_acquire(s->ctx);
193
194 virtio_scsi_clear_aio(s);
195
196 blk_drain_all();
197
198 aio_context_release(s->ctx);
199
200 for (i = 0; i < vs->conf.num_queues + 2; i++) {
201 k->set_host_notifier(qbus->parent, i, false);
202 }
203
204
205 k->set_guest_notifiers(qbus->parent, vs->conf.num_queues + 2, false);
206 s->dataplane_stopping = false;
207 s->dataplane_started = false;
208}
209