1 | /* |
2 | * Virtio PMEM device |
3 | * |
4 | * Copyright (C) 2018-2019 Red Hat, Inc. |
5 | * |
6 | * Authors: |
7 | * Pankaj Gupta <pagupta@redhat.com> |
8 | * David Hildenbrand <david@redhat.com> |
9 | * |
10 | * This work is licensed under the terms of the GNU GPL, version 2. |
11 | * See the COPYING file in the top-level directory. |
12 | */ |
13 | |
14 | #include "qemu/osdep.h" |
15 | #include "qapi/error.h" |
16 | #include "qemu-common.h" |
17 | #include "qemu/error-report.h" |
18 | #include "qemu/main-loop.h" |
19 | #include "hw/virtio/virtio-pmem.h" |
20 | #include "hw/qdev-properties.h" |
21 | #include "hw/virtio/virtio-access.h" |
22 | #include "standard-headers/linux/virtio_ids.h" |
23 | #include "standard-headers/linux/virtio_pmem.h" |
24 | #include "sysemu/hostmem.h" |
25 | #include "block/aio.h" |
26 | #include "block/thread-pool.h" |
27 | |
28 | typedef struct VirtIODeviceRequest { |
29 | VirtQueueElement elem; |
30 | int fd; |
31 | VirtIOPMEM *pmem; |
32 | VirtIODevice *vdev; |
33 | struct virtio_pmem_req req; |
34 | struct virtio_pmem_resp resp; |
35 | } VirtIODeviceRequest; |
36 | |
37 | static int worker_cb(void *opaque) |
38 | { |
39 | VirtIODeviceRequest *req_data = opaque; |
40 | int err = 0; |
41 | |
42 | /* flush raw backing image */ |
43 | err = fsync(req_data->fd); |
44 | if (err != 0) { |
45 | err = 1; |
46 | } |
47 | |
48 | virtio_stw_p(req_data->vdev, &req_data->resp.ret, err); |
49 | |
50 | return 0; |
51 | } |
52 | |
53 | static void done_cb(void *opaque, int ret) |
54 | { |
55 | VirtIODeviceRequest *req_data = opaque; |
56 | int len = iov_from_buf(req_data->elem.in_sg, req_data->elem.in_num, 0, |
57 | &req_data->resp, sizeof(struct virtio_pmem_resp)); |
58 | |
59 | /* Callbacks are serialized, so no need to use atomic ops. */ |
60 | virtqueue_push(req_data->pmem->rq_vq, &req_data->elem, len); |
61 | virtio_notify((VirtIODevice *)req_data->pmem, req_data->pmem->rq_vq); |
62 | g_free(req_data); |
63 | } |
64 | |
65 | static void virtio_pmem_flush(VirtIODevice *vdev, VirtQueue *vq) |
66 | { |
67 | VirtIODeviceRequest *req_data; |
68 | VirtIOPMEM *pmem = VIRTIO_PMEM(vdev); |
69 | HostMemoryBackend *backend = MEMORY_BACKEND(pmem->memdev); |
70 | ThreadPool *pool = aio_get_thread_pool(qemu_get_aio_context()); |
71 | |
72 | req_data = virtqueue_pop(vq, sizeof(VirtIODeviceRequest)); |
73 | if (!req_data) { |
74 | virtio_error(vdev, "virtio-pmem missing request data" ); |
75 | return; |
76 | } |
77 | |
78 | if (req_data->elem.out_num < 1 || req_data->elem.in_num < 1) { |
79 | virtio_error(vdev, "virtio-pmem request not proper" ); |
80 | g_free(req_data); |
81 | return; |
82 | } |
83 | req_data->fd = memory_region_get_fd(&backend->mr); |
84 | req_data->pmem = pmem; |
85 | req_data->vdev = vdev; |
86 | thread_pool_submit_aio(pool, worker_cb, req_data, done_cb, req_data); |
87 | } |
88 | |
89 | static void virtio_pmem_get_config(VirtIODevice *vdev, uint8_t *config) |
90 | { |
91 | VirtIOPMEM *pmem = VIRTIO_PMEM(vdev); |
92 | struct virtio_pmem_config *pmemcfg = (struct virtio_pmem_config *) config; |
93 | |
94 | virtio_stq_p(vdev, &pmemcfg->start, pmem->start); |
95 | virtio_stq_p(vdev, &pmemcfg->size, memory_region_size(&pmem->memdev->mr)); |
96 | } |
97 | |
98 | static uint64_t virtio_pmem_get_features(VirtIODevice *vdev, uint64_t features, |
99 | Error **errp) |
100 | { |
101 | return features; |
102 | } |
103 | |
104 | static void virtio_pmem_realize(DeviceState *dev, Error **errp) |
105 | { |
106 | VirtIODevice *vdev = VIRTIO_DEVICE(dev); |
107 | VirtIOPMEM *pmem = VIRTIO_PMEM(dev); |
108 | |
109 | if (!pmem->memdev) { |
110 | error_setg(errp, "virtio-pmem memdev not set" ); |
111 | return; |
112 | } |
113 | |
114 | if (host_memory_backend_is_mapped(pmem->memdev)) { |
115 | char *path = object_get_canonical_path_component(OBJECT(pmem->memdev)); |
116 | error_setg(errp, "can't use already busy memdev: %s" , path); |
117 | g_free(path); |
118 | return; |
119 | } |
120 | |
121 | host_memory_backend_set_mapped(pmem->memdev, true); |
122 | virtio_init(vdev, TYPE_VIRTIO_PMEM, VIRTIO_ID_PMEM, |
123 | sizeof(struct virtio_pmem_config)); |
124 | pmem->rq_vq = virtio_add_queue(vdev, 128, virtio_pmem_flush); |
125 | } |
126 | |
127 | static void virtio_pmem_unrealize(DeviceState *dev, Error **errp) |
128 | { |
129 | VirtIODevice *vdev = VIRTIO_DEVICE(dev); |
130 | VirtIOPMEM *pmem = VIRTIO_PMEM(dev); |
131 | |
132 | host_memory_backend_set_mapped(pmem->memdev, false); |
133 | virtio_cleanup(vdev); |
134 | } |
135 | |
136 | static void virtio_pmem_fill_device_info(const VirtIOPMEM *pmem, |
137 | VirtioPMEMDeviceInfo *vi) |
138 | { |
139 | vi->memaddr = pmem->start; |
140 | vi->size = memory_region_size(&pmem->memdev->mr); |
141 | vi->memdev = object_get_canonical_path(OBJECT(pmem->memdev)); |
142 | } |
143 | |
144 | static MemoryRegion *virtio_pmem_get_memory_region(VirtIOPMEM *pmem, |
145 | Error **errp) |
146 | { |
147 | if (!pmem->memdev) { |
148 | error_setg(errp, "'%s' property must be set" , VIRTIO_PMEM_MEMDEV_PROP); |
149 | return NULL; |
150 | } |
151 | |
152 | return &pmem->memdev->mr; |
153 | } |
154 | |
155 | static Property virtio_pmem_properties[] = { |
156 | DEFINE_PROP_UINT64(VIRTIO_PMEM_ADDR_PROP, VirtIOPMEM, start, 0), |
157 | DEFINE_PROP_LINK(VIRTIO_PMEM_MEMDEV_PROP, VirtIOPMEM, memdev, |
158 | TYPE_MEMORY_BACKEND, HostMemoryBackend *), |
159 | DEFINE_PROP_END_OF_LIST(), |
160 | }; |
161 | |
162 | static void virtio_pmem_class_init(ObjectClass *klass, void *data) |
163 | { |
164 | DeviceClass *dc = DEVICE_CLASS(klass); |
165 | VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass); |
166 | VirtIOPMEMClass *vpc = VIRTIO_PMEM_CLASS(klass); |
167 | |
168 | dc->props = virtio_pmem_properties; |
169 | |
170 | vdc->realize = virtio_pmem_realize; |
171 | vdc->unrealize = virtio_pmem_unrealize; |
172 | vdc->get_config = virtio_pmem_get_config; |
173 | vdc->get_features = virtio_pmem_get_features; |
174 | |
175 | vpc->fill_device_info = virtio_pmem_fill_device_info; |
176 | vpc->get_memory_region = virtio_pmem_get_memory_region; |
177 | } |
178 | |
179 | static TypeInfo virtio_pmem_info = { |
180 | .name = TYPE_VIRTIO_PMEM, |
181 | .parent = TYPE_VIRTIO_DEVICE, |
182 | .class_size = sizeof(VirtIOPMEMClass), |
183 | .class_init = virtio_pmem_class_init, |
184 | .instance_size = sizeof(VirtIOPMEM), |
185 | }; |
186 | |
187 | static void virtio_register_types(void) |
188 | { |
189 | type_register_static(&virtio_pmem_info); |
190 | } |
191 | |
192 | type_init(virtio_register_types) |
193 | |