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10#include <linux/init.h>
11#include <linux/module.h>
12#include <linux/device.h>
13#include <linux/kernel.h>
14#include <linux/sched.h>
15#include <linux/etherdevice.h>
16#include <linux/vringh.h>
17#include <linux/vdpa.h>
18#include <uapi/linux/virtio_net.h>
19
20#include "vdpa_sim.h"
21
22#define DRV_VERSION "0.1"
23#define DRV_AUTHOR "Jason Wang <jasowang@redhat.com>"
24#define DRV_DESC "vDPA Device Simulator for networking device"
25#define DRV_LICENSE "GPL v2"
26
27#define VDPASIM_NET_FEATURES (VDPASIM_FEATURES | \
28 (1ULL << VIRTIO_NET_F_MAC))
29
30#define VDPASIM_NET_VQ_NUM 2
31
32static char *macaddr;
33module_param(macaddr, charp, 0);
34MODULE_PARM_DESC(macaddr, "Ethernet MAC address");
35
36static u8 macaddr_buf[ETH_ALEN];
37
38static void vdpasim_net_work(struct work_struct *work)
39{
40 struct vdpasim *vdpasim = container_of(work, struct vdpasim, work);
41 struct vdpasim_virtqueue *txq = &vdpasim->vqs[1];
42 struct vdpasim_virtqueue *rxq = &vdpasim->vqs[0];
43 ssize_t read, write;
44 size_t total_write;
45 int pkts = 0;
46 int err;
47
48 spin_lock(&vdpasim->lock);
49
50 if (!(vdpasim->status & VIRTIO_CONFIG_S_DRIVER_OK))
51 goto out;
52
53 if (!txq->ready || !rxq->ready)
54 goto out;
55
56 while (true) {
57 total_write = 0;
58 err = vringh_getdesc_iotlb(&txq->vring, &txq->out_iov, NULL,
59 &txq->head, GFP_ATOMIC);
60 if (err <= 0)
61 break;
62
63 err = vringh_getdesc_iotlb(&rxq->vring, NULL, &rxq->in_iov,
64 &rxq->head, GFP_ATOMIC);
65 if (err <= 0) {
66 vringh_complete_iotlb(&txq->vring, txq->head, 0);
67 break;
68 }
69
70 while (true) {
71 read = vringh_iov_pull_iotlb(&txq->vring, &txq->out_iov,
72 vdpasim->buffer,
73 PAGE_SIZE);
74 if (read <= 0)
75 break;
76
77 write = vringh_iov_push_iotlb(&rxq->vring, &rxq->in_iov,
78 vdpasim->buffer, read);
79 if (write <= 0)
80 break;
81
82 total_write += write;
83 }
84
85
86 smp_wmb();
87
88 vringh_complete_iotlb(&txq->vring, txq->head, 0);
89 vringh_complete_iotlb(&rxq->vring, rxq->head, total_write);
90
91
92 smp_wmb();
93
94 local_bh_disable();
95 if (vringh_need_notify_iotlb(&txq->vring) > 0)
96 vringh_notify(&txq->vring);
97 if (vringh_need_notify_iotlb(&rxq->vring) > 0)
98 vringh_notify(&rxq->vring);
99 local_bh_enable();
100
101 if (++pkts > 4) {
102 schedule_work(&vdpasim->work);
103 goto out;
104 }
105 }
106
107out:
108 spin_unlock(&vdpasim->lock);
109}
110
111static void vdpasim_net_get_config(struct vdpasim *vdpasim, void *config)
112{
113 struct virtio_net_config *net_config = config;
114
115 net_config->mtu = cpu_to_vdpasim16(vdpasim, 1500);
116 net_config->status = cpu_to_vdpasim16(vdpasim, VIRTIO_NET_S_LINK_UP);
117 memcpy(net_config->mac, macaddr_buf, ETH_ALEN);
118}
119
120static void vdpasim_net_mgmtdev_release(struct device *dev)
121{
122}
123
124static struct device vdpasim_net_mgmtdev = {
125 .init_name = "vdpasim_net",
126 .release = vdpasim_net_mgmtdev_release,
127};
128
129static int vdpasim_net_dev_add(struct vdpa_mgmt_dev *mdev, const char *name)
130{
131 struct vdpasim_dev_attr dev_attr = {};
132 struct vdpasim *simdev;
133 int ret;
134
135 dev_attr.mgmt_dev = mdev;
136 dev_attr.name = name;
137 dev_attr.id = VIRTIO_ID_NET;
138 dev_attr.supported_features = VDPASIM_NET_FEATURES;
139 dev_attr.nvqs = VDPASIM_NET_VQ_NUM;
140 dev_attr.config_size = sizeof(struct virtio_net_config);
141 dev_attr.get_config = vdpasim_net_get_config;
142 dev_attr.work_fn = vdpasim_net_work;
143 dev_attr.buffer_size = PAGE_SIZE;
144
145 simdev = vdpasim_create(&dev_attr);
146 if (IS_ERR(simdev))
147 return PTR_ERR(simdev);
148
149 ret = _vdpa_register_device(&simdev->vdpa, VDPASIM_NET_VQ_NUM);
150 if (ret)
151 goto reg_err;
152
153 return 0;
154
155reg_err:
156 put_device(&simdev->vdpa.dev);
157 return ret;
158}
159
160static void vdpasim_net_dev_del(struct vdpa_mgmt_dev *mdev,
161 struct vdpa_device *dev)
162{
163 struct vdpasim *simdev = container_of(dev, struct vdpasim, vdpa);
164
165 _vdpa_unregister_device(&simdev->vdpa);
166}
167
168static const struct vdpa_mgmtdev_ops vdpasim_net_mgmtdev_ops = {
169 .dev_add = vdpasim_net_dev_add,
170 .dev_del = vdpasim_net_dev_del
171};
172
173static struct virtio_device_id id_table[] = {
174 { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID },
175 { 0 },
176};
177
178static struct vdpa_mgmt_dev mgmt_dev = {
179 .device = &vdpasim_net_mgmtdev,
180 .id_table = id_table,
181 .ops = &vdpasim_net_mgmtdev_ops,
182};
183
184static int __init vdpasim_net_init(void)
185{
186 int ret;
187
188 if (macaddr) {
189 mac_pton(macaddr, macaddr_buf);
190 if (!is_valid_ether_addr(macaddr_buf))
191 return -EADDRNOTAVAIL;
192 } else {
193 eth_random_addr(macaddr_buf);
194 }
195
196 ret = device_register(&vdpasim_net_mgmtdev);
197 if (ret)
198 return ret;
199
200 ret = vdpa_mgmtdev_register(&mgmt_dev);
201 if (ret)
202 goto parent_err;
203 return 0;
204
205parent_err:
206 device_unregister(&vdpasim_net_mgmtdev);
207 return ret;
208}
209
210static void __exit vdpasim_net_exit(void)
211{
212 vdpa_mgmtdev_unregister(&mgmt_dev);
213 device_unregister(&vdpasim_net_mgmtdev);
214}
215
216module_init(vdpasim_net_init);
217module_exit(vdpasim_net_exit);
218
219MODULE_VERSION(DRV_VERSION);
220MODULE_LICENSE(DRV_LICENSE);
221MODULE_AUTHOR(DRV_AUTHOR);
222MODULE_DESCRIPTION(DRV_DESC);
223
