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path: root/drivers/vdpa/vdpa_sim/vdpa_sim_net.c
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Diffstat (limited to 'drivers/vdpa/vdpa_sim/vdpa_sim_net.c')
-rw-r--r--drivers/vdpa/vdpa_sim/vdpa_sim_net.c177
1 files changed, 177 insertions, 0 deletions
diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim_net.c b/drivers/vdpa/vdpa_sim/vdpa_sim_net.c
new file mode 100644
index 000000000000..c10b6981fdab
--- /dev/null
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim_net.c
@@ -0,0 +1,177 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * VDPA simulator for networking device.
+ *
+ * Copyright (c) 2020, Red Hat Inc. All rights reserved.
+ * Author: Jason Wang <jasowang@redhat.com>
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/etherdevice.h>
+#include <linux/vringh.h>
+#include <linux/vdpa.h>
+#include <uapi/linux/virtio_net.h>
+
+#include "vdpa_sim.h"
+
+#define DRV_VERSION "0.1"
+#define DRV_AUTHOR "Jason Wang <jasowang@redhat.com>"
+#define DRV_DESC "vDPA Device Simulator for networking device"
+#define DRV_LICENSE "GPL v2"
+
+#define VDPASIM_NET_FEATURES (VDPASIM_FEATURES | \
+ (1ULL << VIRTIO_NET_F_MAC))
+
+#define VDPASIM_NET_VQ_NUM 2
+
+static char *macaddr;
+module_param(macaddr, charp, 0);
+MODULE_PARM_DESC(macaddr, "Ethernet MAC address");
+
+u8 macaddr_buf[ETH_ALEN];
+
+static struct vdpasim *vdpasim_net_dev;
+
+static void vdpasim_net_work(struct work_struct *work)
+{
+ struct vdpasim *vdpasim = container_of(work, struct vdpasim, work);
+ struct vdpasim_virtqueue *txq = &vdpasim->vqs[1];
+ struct vdpasim_virtqueue *rxq = &vdpasim->vqs[0];
+ ssize_t read, write;
+ size_t total_write;
+ int pkts = 0;
+ int err;
+
+ spin_lock(&vdpasim->lock);
+
+ if (!(vdpasim->status & VIRTIO_CONFIG_S_DRIVER_OK))
+ goto out;
+
+ if (!txq->ready || !rxq->ready)
+ goto out;
+
+ while (true) {
+ total_write = 0;
+ err = vringh_getdesc_iotlb(&txq->vring, &txq->out_iov, NULL,
+ &txq->head, GFP_ATOMIC);
+ if (err <= 0)
+ break;
+
+ err = vringh_getdesc_iotlb(&rxq->vring, NULL, &rxq->in_iov,
+ &rxq->head, GFP_ATOMIC);
+ if (err <= 0) {
+ vringh_complete_iotlb(&txq->vring, txq->head, 0);
+ break;
+ }
+
+ while (true) {
+ read = vringh_iov_pull_iotlb(&txq->vring, &txq->out_iov,
+ vdpasim->buffer,
+ PAGE_SIZE);
+ if (read <= 0)
+ break;
+
+ write = vringh_iov_push_iotlb(&rxq->vring, &rxq->in_iov,
+ vdpasim->buffer, read);
+ if (write <= 0)
+ break;
+
+ total_write += write;
+ }
+
+ /* Make sure data is wrote before advancing index */
+ smp_wmb();
+
+ vringh_complete_iotlb(&txq->vring, txq->head, 0);
+ vringh_complete_iotlb(&rxq->vring, rxq->head, total_write);
+
+ /* Make sure used is visible before rasing the interrupt. */
+ smp_wmb();
+
+ local_bh_disable();
+ if (vringh_need_notify_iotlb(&txq->vring) > 0)
+ vringh_notify(&txq->vring);
+ if (vringh_need_notify_iotlb(&rxq->vring) > 0)
+ vringh_notify(&rxq->vring);
+ local_bh_enable();
+
+ if (++pkts > 4) {
+ schedule_work(&vdpasim->work);
+ goto out;
+ }
+ }
+
+out:
+ spin_unlock(&vdpasim->lock);
+}
+
+static void vdpasim_net_get_config(struct vdpasim *vdpasim, void *config)
+{
+ struct virtio_net_config *net_config =
+ (struct virtio_net_config *)config;
+
+ net_config->mtu = cpu_to_vdpasim16(vdpasim, 1500);
+ net_config->status = cpu_to_vdpasim16(vdpasim, VIRTIO_NET_S_LINK_UP);
+ memcpy(net_config->mac, macaddr_buf, ETH_ALEN);
+}
+
+static int __init vdpasim_net_init(void)
+{
+ struct vdpasim_dev_attr dev_attr = {};
+ int ret;
+
+ if (macaddr) {
+ mac_pton(macaddr, macaddr_buf);
+ if (!is_valid_ether_addr(macaddr_buf)) {
+ ret = -EADDRNOTAVAIL;
+ goto out;
+ }
+ } else {
+ eth_random_addr(macaddr_buf);
+ }
+
+ dev_attr.id = VIRTIO_ID_NET;
+ dev_attr.supported_features = VDPASIM_NET_FEATURES;
+ dev_attr.nvqs = VDPASIM_NET_VQ_NUM;
+ dev_attr.config_size = sizeof(struct virtio_net_config);
+ dev_attr.get_config = vdpasim_net_get_config;
+ dev_attr.work_fn = vdpasim_net_work;
+ dev_attr.buffer_size = PAGE_SIZE;
+
+ vdpasim_net_dev = vdpasim_create(&dev_attr);
+ if (IS_ERR(vdpasim_net_dev)) {
+ ret = PTR_ERR(vdpasim_net_dev);
+ goto out;
+ }
+
+ ret = vdpa_register_device(&vdpasim_net_dev->vdpa);
+ if (ret)
+ goto put_dev;
+
+ return 0;
+
+put_dev:
+ put_device(&vdpasim_net_dev->vdpa.dev);
+out:
+ return ret;
+}
+
+static void __exit vdpasim_net_exit(void)
+{
+ struct vdpa_device *vdpa = &vdpasim_net_dev->vdpa;
+
+ vdpa_unregister_device(vdpa);
+}
+
+module_init(vdpasim_net_init);
+module_exit(vdpasim_net_exit);
+
+MODULE_VERSION(DRV_VERSION);
+MODULE_LICENSE(DRV_LICENSE);
+MODULE_AUTHOR(DRV_AUTHOR);
+MODULE_DESCRIPTION(DRV_DESC);