aboutsummaryrefslogtreecommitdiff
path: root/hw/virtio/virtio-pmem.c
blob: ff1a2ddb36d470ce76f60d79b078e761800a5474 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
/*
 * Virtio PMEM device
 *
 * Copyright (C) 2018-2019 Red Hat, Inc.
 *
 * Authors:
 *  Pankaj Gupta <pagupta@redhat.com>
 *  David Hildenbrand <david@redhat.com>
 *
 * This work is licensed under the terms of the GNU GPL, version 2.
 * See the COPYING file in the top-level directory.
 */

#include "qemu/osdep.h"
#include "qapi/error.h"
#include "qemu-common.h"
#include "qemu/error-report.h"
#include "qemu/main-loop.h"
#include "hw/virtio/virtio-pmem.h"
#include "hw/qdev-properties.h"
#include "hw/virtio/virtio-access.h"
#include "standard-headers/linux/virtio_ids.h"
#include "standard-headers/linux/virtio_pmem.h"
#include "block/aio.h"
#include "block/thread-pool.h"

typedef struct VirtIODeviceRequest {
    VirtQueueElement elem;
    int fd;
    VirtIOPMEM *pmem;
    VirtIODevice *vdev;
    struct virtio_pmem_req req;
    struct virtio_pmem_resp resp;
} VirtIODeviceRequest;

static int worker_cb(void *opaque)
{
    VirtIODeviceRequest *req_data = opaque;
    int err = 0;

    /* flush raw backing image */
    err = fsync(req_data->fd);
    if (err != 0) {
        err = 1;
    }

    virtio_stw_p(req_data->vdev, &req_data->resp.ret, err);

    return 0;
}

static void done_cb(void *opaque, int ret)
{
    VirtIODeviceRequest *req_data = opaque;
    int len = iov_from_buf(req_data->elem.in_sg, req_data->elem.in_num, 0,
                              &req_data->resp, sizeof(struct virtio_pmem_resp));

    /* Callbacks are serialized, so no need to use atomic ops. */
    virtqueue_push(req_data->pmem->rq_vq, &req_data->elem, len);
    virtio_notify((VirtIODevice *)req_data->pmem, req_data->pmem->rq_vq);
    g_free(req_data);
}

static void virtio_pmem_flush(VirtIODevice *vdev, VirtQueue *vq)
{
    VirtIODeviceRequest *req_data;
    VirtIOPMEM *pmem = VIRTIO_PMEM(vdev);
    HostMemoryBackend *backend = MEMORY_BACKEND(pmem->memdev);
    ThreadPool *pool = aio_get_thread_pool(qemu_get_aio_context());

    req_data = virtqueue_pop(vq, sizeof(VirtIODeviceRequest));
    if (!req_data) {
        virtio_error(vdev, "virtio-pmem missing request data");
        return;
    }

    if (req_data->elem.out_num < 1 || req_data->elem.in_num < 1) {
        virtio_error(vdev, "virtio-pmem request not proper");
        g_free(req_data);
        return;
    }
    req_data->fd   = memory_region_get_fd(&backend->mr);
    req_data->pmem = pmem;
    req_data->vdev = vdev;
    thread_pool_submit_aio(pool, worker_cb, req_data, done_cb, req_data);
}

static void virtio_pmem_get_config(VirtIODevice *vdev, uint8_t *config)
{
    VirtIOPMEM *pmem = VIRTIO_PMEM(vdev);
    struct virtio_pmem_config *pmemcfg = (struct virtio_pmem_config *) config;

    virtio_stq_p(vdev, &pmemcfg->start, pmem->start);
    virtio_stq_p(vdev, &pmemcfg->size, memory_region_size(&pmem->memdev->mr));
}

static uint64_t virtio_pmem_get_features(VirtIODevice *vdev, uint64_t features,
                                        Error **errp)
{
    return features;
}

static void virtio_pmem_realize(DeviceState *dev, Error **errp)
{
    VirtIODevice *vdev = VIRTIO_DEVICE(dev);
    VirtIOPMEM *pmem = VIRTIO_PMEM(dev);

    if (!pmem->memdev) {
        error_setg(errp, "virtio-pmem memdev not set");
        return;
    }

    if (host_memory_backend_is_mapped(pmem->memdev)) {
        char *path = object_get_canonical_path_component(OBJECT(pmem->memdev));
        error_setg(errp, "can't use already busy memdev: %s", path);
        g_free(path);
        return;
    }

    host_memory_backend_set_mapped(pmem->memdev, true);
    virtio_init(vdev, TYPE_VIRTIO_PMEM, VIRTIO_ID_PMEM,
                sizeof(struct virtio_pmem_config));
    pmem->rq_vq = virtio_add_queue(vdev, 128, virtio_pmem_flush);
}

static void virtio_pmem_unrealize(DeviceState *dev, Error **errp)
{
    VirtIODevice *vdev = VIRTIO_DEVICE(dev);
    VirtIOPMEM *pmem = VIRTIO_PMEM(dev);

    host_memory_backend_set_mapped(pmem->memdev, false);
    virtio_cleanup(vdev);
}

static void virtio_pmem_fill_device_info(const VirtIOPMEM *pmem,
                                         VirtioPMEMDeviceInfo *vi)
{
    vi->memaddr = pmem->start;
    vi->size    = memory_region_size(&pmem->memdev->mr);
    vi->memdev  = object_get_canonical_path(OBJECT(pmem->memdev));
}

static MemoryRegion *virtio_pmem_get_memory_region(VirtIOPMEM *pmem,
                                                   Error **errp)
{
    if (!pmem->memdev) {
        error_setg(errp, "'%s' property must be set", VIRTIO_PMEM_MEMDEV_PROP);
        return NULL;
    }

    return &pmem->memdev->mr;
}

static Property virtio_pmem_properties[] = {
    DEFINE_PROP_UINT64(VIRTIO_PMEM_ADDR_PROP, VirtIOPMEM, start, 0),
    DEFINE_PROP_LINK(VIRTIO_PMEM_MEMDEV_PROP, VirtIOPMEM, memdev,
                     TYPE_MEMORY_BACKEND, HostMemoryBackend *),
    DEFINE_PROP_END_OF_LIST(),
};

static void virtio_pmem_class_init(ObjectClass *klass, void *data)
{
    DeviceClass *dc = DEVICE_CLASS(klass);
    VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
    VirtIOPMEMClass *vpc = VIRTIO_PMEM_CLASS(klass);

    dc->props = virtio_pmem_properties;

    vdc->realize = virtio_pmem_realize;
    vdc->unrealize = virtio_pmem_unrealize;
    vdc->get_config = virtio_pmem_get_config;
    vdc->get_features = virtio_pmem_get_features;

    vpc->fill_device_info = virtio_pmem_fill_device_info;
    vpc->get_memory_region = virtio_pmem_get_memory_region;
}

static TypeInfo virtio_pmem_info = {
    .name          = TYPE_VIRTIO_PMEM,
    .parent        = TYPE_VIRTIO_DEVICE,
    .class_size    = sizeof(VirtIOPMEMClass),
    .class_init    = virtio_pmem_class_init,
    .instance_size = sizeof(VirtIOPMEM),
};

static void virtio_register_types(void)
{
    type_register_static(&virtio_pmem_info);
}

type_init(virtio_register_types)