| Message ID | 20191106133531.693-7-jasowang@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | mdev based hardware virtio offloading support | expand |
On Wed, Nov 06, 2019 at 09:35:31PM +0800, Jason Wang wrote: > This sample driver creates mdev device that simulate virtio net device > over virtio mdev transport. The device is implemented through vringh > and workqueue. A device specific dma ops is to make sure HVA is used > directly as the IOVA. This should be sufficient for kernel virtio > driver to work. > > Only 'virtio' type is supported right now. I plan to add 'vhost' type > on top which requires some virtual IOMMU implemented in this sample > driver. > > Acked-by: Cornelia Huck <cohuck@redhat.com> > Signed-off-by: Jason Wang <jasowang@redhat.com> I'd prefer it that we call this something else, e.g. mvnet-loopback. Just so people don't expect a fully functional device somehow. Can be renamed when applying? > --- > MAINTAINERS | 1 + > samples/Kconfig | 10 + > samples/vfio-mdev/Makefile | 1 + > samples/vfio-mdev/mvnet.c | 686 +++++++++++++++++++++++++++++++++++++ > 4 files changed, 698 insertions(+) > create mode 100644 samples/vfio-mdev/mvnet.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index 4997957443df..6e9ad105a28f 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -17249,6 +17249,7 @@ F: include/uapi/linux/virtio_*.h > F: drivers/crypto/virtio/ > F: mm/balloon_compaction.c > F: include/linux/mdev_virtio_ops.h > +F: samples/vfio-mdev/mvnet.c > > VIRTIO BLOCK AND SCSI DRIVERS > M: "Michael S. Tsirkin" <mst@redhat.com> > diff --git a/samples/Kconfig b/samples/Kconfig > index c8dacb4dda80..13a2443e18e0 100644 > --- a/samples/Kconfig > +++ b/samples/Kconfig > @@ -131,6 +131,16 @@ config SAMPLE_VFIO_MDEV_MDPY > mediated device. It is a simple framebuffer and supports > the region display interface (VFIO_GFX_PLANE_TYPE_REGION). > > +config SAMPLE_VIRTIO_MDEV_NET > + tristate "Build VIRTIO net example mediated device sample code -- loadable modules only" > + depends on VIRTIO_MDEV && VHOST_RING && m > + help > + Build a networking sample device for use as a virtio > + mediated device. The device coopreates with virtio-mdev bus > + driver to present an virtio ethernet driver for > + kernel. It simply loopbacks all packets from its TX > + virtqueue to its RX virtqueue. > + > config SAMPLE_VFIO_MDEV_MDPY_FB > tristate "Build VFIO mdpy example guest fbdev driver -- loadable module only" > depends on FB && m > diff --git a/samples/vfio-mdev/Makefile b/samples/vfio-mdev/Makefile > index 10d179c4fdeb..f34af90ed0a0 100644 > --- a/samples/vfio-mdev/Makefile > +++ b/samples/vfio-mdev/Makefile > @@ -3,3 +3,4 @@ obj-$(CONFIG_SAMPLE_VFIO_MDEV_MTTY) += mtty.o > obj-$(CONFIG_SAMPLE_VFIO_MDEV_MDPY) += mdpy.o > obj-$(CONFIG_SAMPLE_VFIO_MDEV_MDPY_FB) += mdpy-fb.o > obj-$(CONFIG_SAMPLE_VFIO_MDEV_MBOCHS) += mbochs.o > +obj-$(CONFIG_SAMPLE_VIRTIO_MDEV_NET) += mvnet.o > diff --git a/samples/vfio-mdev/mvnet.c b/samples/vfio-mdev/mvnet.c > new file mode 100644 > index 000000000000..a89aecfab68a > --- /dev/null > +++ b/samples/vfio-mdev/mvnet.c > @@ -0,0 +1,686 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Mediated virtual virtio-net device driver. > + * > + * Copyright (c) 2019, Red Hat Inc. All rights reserved. > + * Author: Jason Wang <jasowang@redhat.com> > + * > + * Sample driver that creates mdev device that simulates ethernet loopback > + * device. > + * > + * Usage: > + * > + * # modprobe virtio_mdev > + * # modprobe mvnet > + * # cd /sys/devices/virtual/mvnet/mvnet/mdev_supported_types/mvnet-virtio > + * # echo "83b8f4f2-509f-382f-3c1e-e6bfe0fa1001" > ./create > + * # cd devices/83b8f4f2-509f-382f-3c1e-e6bfe0fa1001 > + * # ls -d virtio0 > + * virtio0 > + */ > + > +#include <linux/init.h> > +#include <linux/module.h> > +#include <linux/device.h> > +#include <linux/kernel.h> > +#include <linux/fs.h> > +#include <linux/poll.h> > +#include <linux/slab.h> > +#include <linux/sched.h> > +#include <linux/wait.h> > +#include <linux/uuid.h> > +#include <linux/iommu.h> > +#include <linux/sysfs.h> > +#include <linux/file.h> > +#include <linux/etherdevice.h> > +#include <linux/mdev.h> > +#include <linux/vringh.h> > +#include <linux/mdev_virtio_ops.h> > +#include <uapi/linux/virtio_config.h> > +#include <uapi/linux/virtio_net.h> > + > +#define VERSION_STRING "0.1" > +#define DRIVER_AUTHOR "Red Hat Corporation" > + > +#define MVNET_CLASS_NAME "mvnet" > +#define MVNET_NAME "mvnet" > + > +/* > + * Global Structures > + */ > + > +static struct mvnet_dev { > + struct class *vd_class; > + struct idr vd_idr; > + struct device dev; > +} mvnet_dev; > + > +struct mvnet_virtqueue { > + struct vringh vring; > + struct vringh_kiov iov; > + unsigned short head; > + bool ready; > + u64 desc_addr; > + u64 device_addr; > + u64 driver_addr; > + u32 num; > + void *private; > + irqreturn_t (*cb)(void *data); > +}; > + > +#define MVNET_QUEUE_ALIGN PAGE_SIZE > +#define MVNET_QUEUE_MAX 256 > +#define MVNET_DEVICE_ID 0x1 > +#define MVNET_VENDOR_ID 0 > + > +u64 mvnet_features = (1ULL << VIRTIO_F_ANY_LAYOUT) | > + (1ULL << VIRTIO_F_VERSION_1) | > + (1ULL << VIRTIO_F_IOMMU_PLATFORM); > + > +/* State of each mdev device */ > +struct mvnet_state { > + struct mvnet_virtqueue vqs[2]; > + struct work_struct work; > + /* spinlock to synchronize virtqueue state */ > + spinlock_t lock; > + struct mdev_device *mdev; > + struct virtio_net_config config; > + void *buffer; > + u32 status; > + u32 generation; > + u64 features; > + struct list_head next; > +}; > + > +static struct mutex mdev_list_lock; > +static struct list_head mdev_devices_list; > + > +static void mvnet_queue_ready(struct mvnet_state *mvnet, unsigned int idx) > +{ > + struct mvnet_virtqueue *vq = &mvnet->vqs[idx]; > + int ret; > + > + ret = vringh_init_kern(&vq->vring, mvnet_features, MVNET_QUEUE_MAX, > + false, (struct vring_desc *)vq->desc_addr, > + (struct vring_avail *)vq->driver_addr, > + (struct vring_used *)vq->device_addr); > +} > + > +static void mvnet_vq_reset(struct mvnet_virtqueue *vq) > +{ > + vq->ready = 0; > + vq->desc_addr = 0; > + vq->driver_addr = 0; > + vq->device_addr = 0; > + vq->cb = NULL; > + vq->private = NULL; > + vringh_init_kern(&vq->vring, mvnet_features, MVNET_QUEUE_MAX, > + false, 0, 0, 0); > +} > + > +static void mvnet_reset(struct mvnet_state *mvnet) > +{ > + int i; > + > + for (i = 0; i < 2; i++) > + mvnet_vq_reset(&mvnet->vqs[i]); > + > + mvnet->features = 0; > + mvnet->status = 0; > + ++mvnet->generation; > +} > + > +static void mvnet_work(struct work_struct *work) > +{ > + struct mvnet_state *mvnet = container_of(work, struct > + mvnet_state, work); > + struct mvnet_virtqueue *txq = &mvnet->vqs[1]; > + struct mvnet_virtqueue *rxq = &mvnet->vqs[0]; > + size_t read, write, total_write; > + int err; > + int pkts = 0; > + > + spin_lock(&mvnet->lock); > + > + if (!txq->ready || !rxq->ready) > + goto out; > + > + while (true) { > + total_write = 0; > + err = vringh_getdesc_kern(&txq->vring, &txq->iov, NULL, > + &txq->head, GFP_ATOMIC); > + if (err <= 0) > + break; > + > + err = vringh_getdesc_kern(&rxq->vring, NULL, &rxq->iov, > + &rxq->head, GFP_ATOMIC); > + if (err <= 0) { > + vringh_complete_kern(&txq->vring, txq->head, 0); > + break; > + } > + > + while (true) { > + read = vringh_iov_pull_kern(&txq->iov, mvnet->buffer, > + PAGE_SIZE); > + if (read <= 0) > + break; > + > + write = vringh_iov_push_kern(&rxq->iov, mvnet->buffer, > + read); > + if (write <= 0) > + break; > + > + total_write += write; > + } > + > + /* Make sure data is wrote before advancing index */ > + smp_wmb(); > + > + vringh_complete_kern(&txq->vring, txq->head, 0); > + vringh_complete_kern(&rxq->vring, rxq->head, total_write); > + > + /* Make sure used is visible before rasing the interrupt. */ > + smp_wmb(); > + > + local_bh_disable(); > + if (txq->cb) > + txq->cb(txq->private); > + if (rxq->cb) > + rxq->cb(rxq->private); > + local_bh_enable(); > + > + if (++pkts > 4) { > + schedule_work(&mvnet->work); > + goto out; > + } > + } > + > +out: > + spin_unlock(&mvnet->lock); > +} > + > +static dma_addr_t mvnet_map_page(struct device *dev, struct page *page, > + unsigned long offset, size_t size, > + enum dma_data_direction dir, > + unsigned long attrs) > +{ > + /* Vringh can only use HVA */ > + return (dma_addr_t)(page_address(page) + offset); > +} > + > +static void mvnet_unmap_page(struct device *dev, dma_addr_t dma_addr, > + size_t size, enum dma_data_direction dir, > + unsigned long attrs) > +{ > +} > + > +static void *mvnet_alloc_coherent(struct device *dev, size_t size, > + dma_addr_t *dma_addr, gfp_t flag, > + unsigned long attrs) > +{ > + void *addr = kmalloc(size, flag); > + > + if (!addr) > + *dma_addr = DMA_MAPPING_ERROR; > + else > + *dma_addr = (dma_addr_t)addr; > + > + return addr; > +} > + > +static void mvnet_free_coherent(struct device *dev, size_t size, > + void *vaddr, dma_addr_t dma_addr, > + unsigned long attrs) > +{ > + kfree((void *)dma_addr); > +} > + > +static const struct dma_map_ops mvnet_dma_ops = { > + .map_page = mvnet_map_page, > + .unmap_page = mvnet_unmap_page, > + .alloc = mvnet_alloc_coherent, > + .free = mvnet_free_coherent, > +}; > + > +static const struct mdev_virtio_device_ops mdev_virtio_ops; > + > +static int mvnet_create(struct kobject *kobj, struct mdev_device *mdev) > +{ > + struct mvnet_state *mvnet; > + struct virtio_net_config *config; > + struct device *dev = mdev_dev(mdev); > + > + if (!mdev) > + return -EINVAL; > + > + mvnet = kzalloc(sizeof(*mvnet), GFP_KERNEL); > + if (!mvnet) > + return -ENOMEM; > + > + mvnet->buffer = kmalloc(PAGE_SIZE, GFP_KERNEL); > + if (!mvnet->buffer) { > + kfree(mvnet); > + return -ENOMEM; > + } > + > + config = &mvnet->config; > + config->mtu = 1500; > + config->status = VIRTIO_NET_S_LINK_UP; > + eth_random_addr(config->mac); > + > + INIT_WORK(&mvnet->work, mvnet_work); > + > + spin_lock_init(&mvnet->lock); > + mvnet->mdev = mdev; > + mdev_set_drvdata(mdev, mvnet); > + > + mutex_lock(&mdev_list_lock); > + list_add(&mvnet->next, &mdev_devices_list); > + mutex_unlock(&mdev_list_lock); > + > + dev->coherent_dma_mask = DMA_BIT_MASK(64); > + set_dma_ops(dev, &mvnet_dma_ops); > + > + mdev_set_virtio_ops(mdev, &mdev_virtio_ops); > + > + return 0; > +} > + > +static int mvnet_remove(struct mdev_device *mdev) > +{ > + struct mvnet_state *mds, *tmp_mds; > + struct mvnet_state *mvnet = mdev_get_drvdata(mdev); > + int ret = -EINVAL; > + > + mutex_lock(&mdev_list_lock); > + list_for_each_entry_safe(mds, tmp_mds, &mdev_devices_list, next) { > + if (mvnet == mds) { > + list_del(&mvnet->next); > + mdev_set_drvdata(mdev, NULL); > + kfree(mvnet->buffer); > + kfree(mvnet); > + ret = 0; > + break; > + } > + } > + mutex_unlock(&mdev_list_lock); > + > + return ret; > +} > + > +static ssize_t > +sample_mvnet_dev_show(struct device *dev, struct device_attribute *attr, > + char *buf) > +{ > + if (mdev_from_dev(dev)) > + return sprintf(buf, "This is MDEV %s\n", dev_name(dev)); > + > + return sprintf(buf, "\n"); > +} > + > +static DEVICE_ATTR_RO(sample_mvnet_dev); > + > +static struct attribute *mvnet_dev_attrs[] = { > + &dev_attr_sample_mvnet_dev.attr, > + NULL, > +}; > + > +static const struct attribute_group mvnet_dev_group = { > + .name = "mvnet_dev", > + .attrs = mvnet_dev_attrs, > +}; > + > +static const struct attribute_group *mvnet_dev_groups[] = { > + &mvnet_dev_group, > + NULL, > +}; > + > +static ssize_t > +sample_mdev_dev_show(struct device *dev, struct device_attribute *attr, > + char *buf) > +{ > + if (mdev_from_dev(dev)) > + return sprintf(buf, "This is MDEV %s\n", dev_name(dev)); > + > + return sprintf(buf, "\n"); > +} > + > +static DEVICE_ATTR_RO(sample_mdev_dev); > + > +static struct attribute *mdev_dev_attrs[] = { > + &dev_attr_sample_mdev_dev.attr, > + NULL, > +}; > + > +static const struct attribute_group mdev_dev_group = { > + .name = "vendor", > + .attrs = mdev_dev_attrs, > +}; > + > +static const struct attribute_group *mdev_dev_groups[] = { > + &mdev_dev_group, > + NULL, > +}; > + > +#define MVNET_STRING_LEN 16 > + > +static ssize_t > +name_show(struct kobject *kobj, struct device *dev, char *buf) > +{ > + char name[MVNET_STRING_LEN]; > + const char *name_str = "virtio-net"; > + > + snprintf(name, MVNET_STRING_LEN, "%s", dev_driver_string(dev)); > + if (!strcmp(kobj->name, name)) > + return sprintf(buf, "%s\n", name_str); > + > + return -EINVAL; > +} > + > +static MDEV_TYPE_ATTR_RO(name); > + > +static ssize_t > +available_instances_show(struct kobject *kobj, struct device *dev, char *buf) > +{ > + return sprintf(buf, "%d\n", INT_MAX); > +} > + > +static MDEV_TYPE_ATTR_RO(available_instances); > + > +static ssize_t device_api_show(struct kobject *kobj, struct device *dev, > + char *buf) > +{ > + return sprintf(buf, "%s\n", VIRTIO_MDEV_DEVICE_API_STRING); > +} > + > +static MDEV_TYPE_ATTR_RO(device_api); > + > +static struct attribute *mdev_types_attrs[] = { > + &mdev_type_attr_name.attr, > + &mdev_type_attr_device_api.attr, > + &mdev_type_attr_available_instances.attr, > + NULL, > +}; > + > +static struct attribute_group mdev_type_group = { > + .name = "virtio", > + .attrs = mdev_types_attrs, > +}; > + > +/* TBD: "vhost" type */ > + > +static struct attribute_group *mdev_type_groups[] = { > + &mdev_type_group, > + NULL, > +}; > + > +static int mvnet_set_vq_address(struct mdev_device *mdev, u16 idx, > + u64 desc_area, u64 driver_area, u64 device_area) > +{ > + struct mvnet_state *mvnet = mdev_get_drvdata(mdev); > + struct mvnet_virtqueue *vq = &mvnet->vqs[idx]; > + > + vq->desc_addr = desc_area; > + vq->driver_addr = driver_area; > + vq->device_addr = device_area; > + > + return 0; > +} > + > +static void mvnet_set_vq_num(struct mdev_device *mdev, u16 idx, u32 num) > +{ > + struct mvnet_state *mvnet = mdev_get_drvdata(mdev); > + struct mvnet_virtqueue *vq = &mvnet->vqs[idx]; > + > + vq->num = num; > +} > + > +static void mvnet_kick_vq(struct mdev_device *mdev, u16 idx) > +{ > + struct mvnet_state *mvnet = mdev_get_drvdata(mdev); > + struct mvnet_virtqueue *vq = &mvnet->vqs[idx]; > + > + if (vq->ready) > + schedule_work(&mvnet->work); > +} > + > +static void mvnet_set_vq_cb(struct mdev_device *mdev, u16 idx, > + struct virtio_mdev_callback *cb) > +{ > + struct mvnet_state *mvnet = mdev_get_drvdata(mdev); > + struct mvnet_virtqueue *vq = &mvnet->vqs[idx]; > + > + vq->cb = cb->callback; > + vq->private = cb->private; > +} > + > +static void mvnet_set_vq_ready(struct mdev_device *mdev, u16 idx, bool ready) > +{ > + struct mvnet_state *mvnet = mdev_get_drvdata(mdev); > + struct mvnet_virtqueue *vq = &mvnet->vqs[idx]; > + > + spin_lock(&mvnet->lock); > + vq->ready = ready; > + if (vq->ready) > + mvnet_queue_ready(mvnet, idx); > + spin_unlock(&mvnet->lock); > +} > + > +static bool mvnet_get_vq_ready(struct mdev_device *mdev, u16 idx) > +{ > + struct mvnet_state *mvnet = mdev_get_drvdata(mdev); > + struct mvnet_virtqueue *vq = &mvnet->vqs[idx]; > + > + return vq->ready; > +} > + > +static int mvnet_set_vq_state(struct mdev_device *mdev, u16 idx, u64 state) > +{ > + struct mvnet_state *mvnet = mdev_get_drvdata(mdev); > + struct mvnet_virtqueue *vq = &mvnet->vqs[idx]; > + struct vringh *vrh = &vq->vring; > + > + spin_lock(&mvnet->lock); > + vrh->last_avail_idx = state; > + spin_unlock(&mvnet->lock); > + > + return 0; > +} > + > +static u64 mvnet_get_vq_state(struct mdev_device *mdev, u16 idx) > +{ > + struct mvnet_state *mvnet = mdev_get_drvdata(mdev); > + struct mvnet_virtqueue *vq = &mvnet->vqs[idx]; > + struct vringh *vrh = &vq->vring; > + > + return vrh->last_avail_idx; > +} > + > +static u16 mvnet_get_vq_align(struct mdev_device *mdev) > +{ > + return MVNET_QUEUE_ALIGN; > +} > + > +static u64 mvnet_get_features(struct mdev_device *mdev) > +{ > + return mvnet_features; > +} > + > +static int mvnet_set_features(struct mdev_device *mdev, u64 features) > +{ > + struct mvnet_state *mvnet = mdev_get_drvdata(mdev); > + > + /* DMA mapping must be done by driver */ > + if (!(features & (1ULL << VIRTIO_F_IOMMU_PLATFORM))) > + return -EINVAL; > + > + mvnet->features = features & mvnet_features; > + > + return 0; > +} > + > +static void mvnet_set_config_cb(struct mdev_device *mdev, > + struct virtio_mdev_callback *cb) > +{ > + /* We don't support config interrupt */ > +} > + > +static u16 mvnet_get_vq_num_max(struct mdev_device *mdev) > +{ > + return MVNET_QUEUE_MAX; > +} > + > +static u32 mvnet_get_device_id(struct mdev_device *mdev) > +{ > + return MVNET_DEVICE_ID; > +} > + > +static u32 mvnet_get_vendor_id(struct mdev_device *mdev) > +{ > + return MVNET_VENDOR_ID; > +} > + > +static u8 mvnet_get_status(struct mdev_device *mdev) > +{ > + struct mvnet_state *mvnet = mdev_get_drvdata(mdev); > + > + return mvnet->status; > +} > + > +static void mvnet_set_status(struct mdev_device *mdev, u8 status) > +{ > + struct mvnet_state *mvnet = mdev_get_drvdata(mdev); > + > + mvnet->status = status; > + > + if (status == 0) { > + spin_lock(&mvnet->lock); > + mvnet_reset(mvnet); > + spin_unlock(&mvnet->lock); > + } > +} > + > +static void mvnet_get_config(struct mdev_device *mdev, unsigned int offset, > + void *buf, unsigned int len) > +{ > + struct mvnet_state *mvnet = mdev_get_drvdata(mdev); > + > + if (offset + len < sizeof(struct virtio_net_config)) > + memcpy(buf, &mvnet->config + offset, len); > +} > + > +static void mvnet_set_config(struct mdev_device *mdev, unsigned int offset, > + const void *buf, unsigned int len) > +{ > + /* No writable config supportted by mvnet */ > +} > + > +static u32 mvnet_get_generation(struct mdev_device *mdev) > +{ > + struct mvnet_state *mvnet = mdev_get_drvdata(mdev); > + > + return mvnet->generation; > +} > + > +static const struct mdev_virtio_device_ops mdev_virtio_ops = { > + .set_vq_address = mvnet_set_vq_address, > + .set_vq_num = mvnet_set_vq_num, > + .kick_vq = mvnet_kick_vq, > + .set_vq_cb = mvnet_set_vq_cb, > + .set_vq_ready = mvnet_set_vq_ready, > + .get_vq_ready = mvnet_get_vq_ready, > + .set_vq_state = mvnet_set_vq_state, > + .get_vq_state = mvnet_get_vq_state, > + .get_vq_align = mvnet_get_vq_align, > + .get_features = mvnet_get_features, > + .set_features = mvnet_set_features, > + .set_config_cb = mvnet_set_config_cb, > + .get_vq_num_max = mvnet_get_vq_num_max, > + .get_device_id = mvnet_get_device_id, > + .get_vendor_id = mvnet_get_vendor_id, > + .get_status = mvnet_get_status, > + .set_status = mvnet_set_status, > + .get_config = mvnet_get_config, > + .set_config = mvnet_set_config, > + .get_generation = mvnet_get_generation, > +}; > + > +static const struct mdev_parent_ops mdev_fops = { > + .owner = THIS_MODULE, > + .dev_attr_groups = mvnet_dev_groups, > + .mdev_attr_groups = mdev_dev_groups, > + .supported_type_groups = mdev_type_groups, > + .create = mvnet_create, > + .remove = mvnet_remove, > +}; > + > +static void mvnet_device_release(struct device *dev) > +{ > + dev_dbg(dev, "mvnet: released\n"); > +} > + > +static int __init mvnet_dev_init(void) > +{ > + int ret = 0; > + > + pr_info("mvnet_dev: %s\n", __func__); > + > + memset(&mvnet_dev, 0, sizeof(mvnet_dev)); > + > + idr_init(&mvnet_dev.vd_idr); > + > + mvnet_dev.vd_class = class_create(THIS_MODULE, MVNET_CLASS_NAME); > + > + if (IS_ERR(mvnet_dev.vd_class)) { > + pr_err("Error: failed to register mvnet_dev class\n"); > + ret = PTR_ERR(mvnet_dev.vd_class); > + goto failed1; > + } > + > + mvnet_dev.dev.class = mvnet_dev.vd_class; > + mvnet_dev.dev.release = mvnet_device_release; > + dev_set_name(&mvnet_dev.dev, "%s", MVNET_NAME); > + > + ret = device_register(&mvnet_dev.dev); > + if (ret) > + goto failed2; > + > + ret = mdev_register_device(&mvnet_dev.dev, &mdev_fops); > + if (ret) > + goto failed3; > + > + mutex_init(&mdev_list_lock); > + INIT_LIST_HEAD(&mdev_devices_list); > + > + goto all_done; > + > +failed3: > + > + device_unregister(&mvnet_dev.dev); > +failed2: > + class_destroy(mvnet_dev.vd_class); > + > +failed1: > +all_done: > + return ret; > +} > + > +static void __exit mvnet_dev_exit(void) > +{ > + mvnet_dev.dev.bus = NULL; > + mdev_unregister_device(&mvnet_dev.dev); > + > + device_unregister(&mvnet_dev.dev); > + idr_destroy(&mvnet_dev.vd_idr); > + class_destroy(mvnet_dev.vd_class); > + mvnet_dev.vd_class = NULL; > + pr_info("mvnet_dev: Unloaded!\n"); > +} > + > +module_init(mvnet_dev_init) > +module_exit(mvnet_dev_exit) > + > +MODULE_LICENSE("GPL v2"); > +MODULE_INFO(supported, "Simulate loopback ethernet device over mdev"); > +MODULE_VERSION(VERSION_STRING); > +MODULE_AUTHOR(DRIVER_AUTHOR); > -- > 2.19.1
On 2019/11/7 下午5:08, Michael S. Tsirkin wrote: > On Wed, Nov 06, 2019 at 09:35:31PM +0800, Jason Wang wrote: >> This sample driver creates mdev device that simulate virtio net device >> over virtio mdev transport. The device is implemented through vringh >> and workqueue. A device specific dma ops is to make sure HVA is used >> directly as the IOVA. This should be sufficient for kernel virtio >> driver to work. >> >> Only 'virtio' type is supported right now. I plan to add 'vhost' type >> on top which requires some virtual IOMMU implemented in this sample >> driver. >> >> Acked-by: Cornelia Huck<cohuck@redhat.com> >> Signed-off-by: Jason Wang<jasowang@redhat.com> > I'd prefer it that we call this something else, e.g. > mvnet-loopback. Just so people don't expect a fully > functional device somehow. Can be renamed when applying? Actually, I plan to extend it as another standard network interface for kernel. It could be either a standalone pseudo device or a stack device. Does this sounds good to you? Thanks > >
On Thu, Nov 07, 2019 at 06:18:45PM +0800, Jason Wang wrote: > > On 2019/11/7 下午5:08, Michael S. Tsirkin wrote: > > On Wed, Nov 06, 2019 at 09:35:31PM +0800, Jason Wang wrote: > > > This sample driver creates mdev device that simulate virtio net device > > > over virtio mdev transport. The device is implemented through vringh > > > and workqueue. A device specific dma ops is to make sure HVA is used > > > directly as the IOVA. This should be sufficient for kernel virtio > > > driver to work. > > > > > > Only 'virtio' type is supported right now. I plan to add 'vhost' type > > > on top which requires some virtual IOMMU implemented in this sample > > > driver. > > > > > > Acked-by: Cornelia Huck<cohuck@redhat.com> > > > Signed-off-by: Jason Wang<jasowang@redhat.com> > > I'd prefer it that we call this something else, e.g. > > mvnet-loopback. Just so people don't expect a fully > > functional device somehow. Can be renamed when applying? > > > Actually, I plan to extend it as another standard network interface for > kernel. It could be either a standalone pseudo device or a stack device. > Does this sounds good to you? > > Thanks That's a big change in an interface so it's a good reason to rename the driver at that point right? Oherwise users of an old kernel would expect a stacked driver and get a loopback instead. Or did I miss something? > > > > >
On 2019/11/7 下午7:21, Michael S. Tsirkin wrote: > On Thu, Nov 07, 2019 at 06:18:45PM +0800, Jason Wang wrote: >> On 2019/11/7 下午5:08, Michael S. Tsirkin wrote: >>> On Wed, Nov 06, 2019 at 09:35:31PM +0800, Jason Wang wrote: >>>> This sample driver creates mdev device that simulate virtio net device >>>> over virtio mdev transport. The device is implemented through vringh >>>> and workqueue. A device specific dma ops is to make sure HVA is used >>>> directly as the IOVA. This should be sufficient for kernel virtio >>>> driver to work. >>>> >>>> Only 'virtio' type is supported right now. I plan to add 'vhost' type >>>> on top which requires some virtual IOMMU implemented in this sample >>>> driver. >>>> >>>> Acked-by: Cornelia Huck<cohuck@redhat.com> >>>> Signed-off-by: Jason Wang<jasowang@redhat.com> >>> I'd prefer it that we call this something else, e.g. >>> mvnet-loopback. Just so people don't expect a fully >>> functional device somehow. Can be renamed when applying? >> Actually, I plan to extend it as another standard network interface for >> kernel. It could be either a standalone pseudo device or a stack device. >> Does this sounds good to you? >> >> Thanks > That's a big change in an interface so it's a good reason > to rename the driver at that point right? > Oherwise users of an old kernel would expect a stacked driver > and get a loopback instead. > > Or did I miss something? My understanding is that it was a sample driver in /doc. It should not be used in production environment. Otherwise we need to move it to driver/virtio. But if you insist, I can post a V11. Thanks
On 2019/11/7 下午8:43, Jason Wang wrote: > > On 2019/11/7 下午7:21, Michael S. Tsirkin wrote: >> On Thu, Nov 07, 2019 at 06:18:45PM +0800, Jason Wang wrote: >>> On 2019/11/7 下午5:08, Michael S. Tsirkin wrote: >>>> On Wed, Nov 06, 2019 at 09:35:31PM +0800, Jason Wang wrote: >>>>> This sample driver creates mdev device that simulate virtio net >>>>> device >>>>> over virtio mdev transport. The device is implemented through vringh >>>>> and workqueue. A device specific dma ops is to make sure HVA is used >>>>> directly as the IOVA. This should be sufficient for kernel virtio >>>>> driver to work. >>>>> >>>>> Only 'virtio' type is supported right now. I plan to add 'vhost' type >>>>> on top which requires some virtual IOMMU implemented in this sample >>>>> driver. >>>>> >>>>> Acked-by: Cornelia Huck<cohuck@redhat.com> >>>>> Signed-off-by: Jason Wang<jasowang@redhat.com> >>>> I'd prefer it that we call this something else, e.g. >>>> mvnet-loopback. Just so people don't expect a fully >>>> functional device somehow. Can be renamed when applying? >>> Actually, I plan to extend it as another standard network interface for >>> kernel. It could be either a standalone pseudo device or a stack >>> device. >>> Does this sounds good to you? >>> >>> Thanks >> That's a big change in an interface so it's a good reason >> to rename the driver at that point right? >> Oherwise users of an old kernel would expect a stacked driver >> and get a loopback instead. >> >> Or did I miss something? > > > My understanding is that it was a sample driver in /doc. It should not > be used in production environment. Otherwise we need to move it to > driver/virtio. > > But if you insist, I can post a V11. > > Thanks Or maybe it's better to rename the type of current mdev from 'virtio' to 'virtio-loopback'. Then we can add more types in the future. Thanks
On Thu, Nov 07, 2019 at 08:47:06PM +0800, Jason Wang wrote: > > On 2019/11/7 下午8:43, Jason Wang wrote: > > > > On 2019/11/7 下午7:21, Michael S. Tsirkin wrote: > > > On Thu, Nov 07, 2019 at 06:18:45PM +0800, Jason Wang wrote: > > > > On 2019/11/7 下午5:08, Michael S. Tsirkin wrote: > > > > > On Wed, Nov 06, 2019 at 09:35:31PM +0800, Jason Wang wrote: > > > > > > This sample driver creates mdev device that simulate > > > > > > virtio net device > > > > > > over virtio mdev transport. The device is implemented through vringh > > > > > > and workqueue. A device specific dma ops is to make sure HVA is used > > > > > > directly as the IOVA. This should be sufficient for kernel virtio > > > > > > driver to work. > > > > > > > > > > > > Only 'virtio' type is supported right now. I plan to add 'vhost' type > > > > > > on top which requires some virtual IOMMU implemented in this sample > > > > > > driver. > > > > > > > > > > > > Acked-by: Cornelia Huck<cohuck@redhat.com> > > > > > > Signed-off-by: Jason Wang<jasowang@redhat.com> > > > > > I'd prefer it that we call this something else, e.g. > > > > > mvnet-loopback. Just so people don't expect a fully > > > > > functional device somehow. Can be renamed when applying? > > > > Actually, I plan to extend it as another standard network interface for > > > > kernel. It could be either a standalone pseudo device or a stack > > > > device. > > > > Does this sounds good to you? > > > > > > > > Thanks > > > That's a big change in an interface so it's a good reason > > > to rename the driver at that point right? > > > Oherwise users of an old kernel would expect a stacked driver > > > and get a loopback instead. > > > > > > Or did I miss something? > > > > > > My understanding is that it was a sample driver in /doc. It should not > > be used in production environment. Otherwise we need to move it to > > driver/virtio. > > > > But if you insist, I can post a V11. > > > > Thanks > > > Or maybe it's better to rename the type of current mdev from 'virtio' to > 'virtio-loopback'. Then we can add more types in the future. > > Thanks > Maybe but is virtio actually a loopback somehow? I thought we can bind a regular virtio device there, no?
On Thu, Nov 07, 2019 at 08:43:29PM +0800, Jason Wang wrote: > > On 2019/11/7 下午7:21, Michael S. Tsirkin wrote: > > On Thu, Nov 07, 2019 at 06:18:45PM +0800, Jason Wang wrote: > > > On 2019/11/7 下午5:08, Michael S. Tsirkin wrote: > > > > On Wed, Nov 06, 2019 at 09:35:31PM +0800, Jason Wang wrote: > > > > > This sample driver creates mdev device that simulate virtio net device > > > > > over virtio mdev transport. The device is implemented through vringh > > > > > and workqueue. A device specific dma ops is to make sure HVA is used > > > > > directly as the IOVA. This should be sufficient for kernel virtio > > > > > driver to work. > > > > > > > > > > Only 'virtio' type is supported right now. I plan to add 'vhost' type > > > > > on top which requires some virtual IOMMU implemented in this sample > > > > > driver. > > > > > > > > > > Acked-by: Cornelia Huck<cohuck@redhat.com> > > > > > Signed-off-by: Jason Wang<jasowang@redhat.com> > > > > I'd prefer it that we call this something else, e.g. > > > > mvnet-loopback. Just so people don't expect a fully > > > > functional device somehow. Can be renamed when applying? > > > Actually, I plan to extend it as another standard network interface for > > > kernel. It could be either a standalone pseudo device or a stack device. > > > Does this sounds good to you? > > > > > > Thanks > > That's a big change in an interface so it's a good reason > > to rename the driver at that point right? > > Oherwise users of an old kernel would expect a stacked driver > > and get a loopback instead. > > > > Or did I miss something? > > > My understanding is that it was a sample driver in /doc. It should not be > used in production environment. Otherwise we need to move it to > driver/virtio. > > But if you insist, I can post a V11. > > Thanks this can be a patch on top.
On 2019/11/7 下午9:08, Michael S. Tsirkin wrote: > On Thu, Nov 07, 2019 at 08:43:29PM +0800, Jason Wang wrote: >> On 2019/11/7 下午7:21, Michael S. Tsirkin wrote: >>> On Thu, Nov 07, 2019 at 06:18:45PM +0800, Jason Wang wrote: >>>> On 2019/11/7 下午5:08, Michael S. Tsirkin wrote: >>>>> On Wed, Nov 06, 2019 at 09:35:31PM +0800, Jason Wang wrote: >>>>>> This sample driver creates mdev device that simulate virtio net device >>>>>> over virtio mdev transport. The device is implemented through vringh >>>>>> and workqueue. A device specific dma ops is to make sure HVA is used >>>>>> directly as the IOVA. This should be sufficient for kernel virtio >>>>>> driver to work. >>>>>> >>>>>> Only 'virtio' type is supported right now. I plan to add 'vhost' type >>>>>> on top which requires some virtual IOMMU implemented in this sample >>>>>> driver. >>>>>> >>>>>> Acked-by: Cornelia Huck<cohuck@redhat.com> >>>>>> Signed-off-by: Jason Wang<jasowang@redhat.com> >>>>> I'd prefer it that we call this something else, e.g. >>>>> mvnet-loopback. Just so people don't expect a fully >>>>> functional device somehow. Can be renamed when applying? >>>> Actually, I plan to extend it as another standard network interface for >>>> kernel. It could be either a standalone pseudo device or a stack device. >>>> Does this sounds good to you? >>>> >>>> Thanks >>> That's a big change in an interface so it's a good reason >>> to rename the driver at that point right? >>> Oherwise users of an old kernel would expect a stacked driver >>> and get a loopback instead. >>> >>> Or did I miss something? >> >> My understanding is that it was a sample driver in /doc. It should not be >> used in production environment. Otherwise we need to move it to >> driver/virtio. >> >> But if you insist, I can post a V11. >> >> Thanks > this can be a patch on top. Then maybe it's better just extend it to work as a normal networking device on top? Thanks
On 2019/11/7 下午9:08, Michael S. Tsirkin wrote: > On Thu, Nov 07, 2019 at 08:47:06PM +0800, Jason Wang wrote: >> On 2019/11/7 下午8:43, Jason Wang wrote: >>> On 2019/11/7 下午7:21, Michael S. Tsirkin wrote: >>>> On Thu, Nov 07, 2019 at 06:18:45PM +0800, Jason Wang wrote: >>>>> On 2019/11/7 下午5:08, Michael S. Tsirkin wrote: >>>>>> On Wed, Nov 06, 2019 at 09:35:31PM +0800, Jason Wang wrote: >>>>>>> This sample driver creates mdev device that simulate >>>>>>> virtio net device >>>>>>> over virtio mdev transport. The device is implemented through vringh >>>>>>> and workqueue. A device specific dma ops is to make sure HVA is used >>>>>>> directly as the IOVA. This should be sufficient for kernel virtio >>>>>>> driver to work. >>>>>>> >>>>>>> Only 'virtio' type is supported right now. I plan to add 'vhost' type >>>>>>> on top which requires some virtual IOMMU implemented in this sample >>>>>>> driver. >>>>>>> >>>>>>> Acked-by: Cornelia Huck<cohuck@redhat.com> >>>>>>> Signed-off-by: Jason Wang<jasowang@redhat.com> >>>>>> I'd prefer it that we call this something else, e.g. >>>>>> mvnet-loopback. Just so people don't expect a fully >>>>>> functional device somehow. Can be renamed when applying? >>>>> Actually, I plan to extend it as another standard network interface for >>>>> kernel. It could be either a standalone pseudo device or a stack >>>>> device. >>>>> Does this sounds good to you? >>>>> >>>>> Thanks >>>> That's a big change in an interface so it's a good reason >>>> to rename the driver at that point right? >>>> Oherwise users of an old kernel would expect a stacked driver >>>> and get a loopback instead. >>>> >>>> Or did I miss something? >>> >>> My understanding is that it was a sample driver in /doc. It should not >>> be used in production environment. Otherwise we need to move it to >>> driver/virtio. >>> >>> But if you insist, I can post a V11. >>> >>> Thanks >> >> Or maybe it's better to rename the type of current mdev from 'virtio' to >> 'virtio-loopback'. Then we can add more types in the future. >> >> Thanks >> > Maybe but is virtio actually a loopback somehow? I thought we > can bind a regular virtio device there, no? It has a prefix, so user will see "mvnet-virtio-loopback". Thanks >
On Thu, Nov 07, 2019 at 09:32:29PM +0800, Jason Wang wrote: > > On 2019/11/7 下午9:08, Michael S. Tsirkin wrote: > > On Thu, Nov 07, 2019 at 08:43:29PM +0800, Jason Wang wrote: > > > On 2019/11/7 下午7:21, Michael S. Tsirkin wrote: > > > > On Thu, Nov 07, 2019 at 06:18:45PM +0800, Jason Wang wrote: > > > > > On 2019/11/7 下午5:08, Michael S. Tsirkin wrote: > > > > > > On Wed, Nov 06, 2019 at 09:35:31PM +0800, Jason Wang wrote: > > > > > > > This sample driver creates mdev device that simulate virtio net device > > > > > > > over virtio mdev transport. The device is implemented through vringh > > > > > > > and workqueue. A device specific dma ops is to make sure HVA is used > > > > > > > directly as the IOVA. This should be sufficient for kernel virtio > > > > > > > driver to work. > > > > > > > > > > > > > > Only 'virtio' type is supported right now. I plan to add 'vhost' type > > > > > > > on top which requires some virtual IOMMU implemented in this sample > > > > > > > driver. > > > > > > > > > > > > > > Acked-by: Cornelia Huck<cohuck@redhat.com> > > > > > > > Signed-off-by: Jason Wang<jasowang@redhat.com> > > > > > > I'd prefer it that we call this something else, e.g. > > > > > > mvnet-loopback. Just so people don't expect a fully > > > > > > functional device somehow. Can be renamed when applying? > > > > > Actually, I plan to extend it as another standard network interface for > > > > > kernel. It could be either a standalone pseudo device or a stack device. > > > > > Does this sounds good to you? > > > > > > > > > > Thanks > > > > That's a big change in an interface so it's a good reason > > > > to rename the driver at that point right? > > > > Oherwise users of an old kernel would expect a stacked driver > > > > and get a loopback instead. > > > > > > > > Or did I miss something? > > > > > > My understanding is that it was a sample driver in /doc. It should not be > > > used in production environment. Otherwise we need to move it to > > > driver/virtio. > > > > > > But if you insist, I can post a V11. > > > > > > Thanks > > this can be a patch on top. > > > Then maybe it's better just extend it to work as a normal networking device > on top? > > Thanks That would be a substantial change. Maybe drop 6/6 for now until we have a better handle on this?
On Thu, Nov 07, 2019 at 09:40:09PM +0800, Jason Wang wrote: > > On 2019/11/7 下午9:08, Michael S. Tsirkin wrote: > > On Thu, Nov 07, 2019 at 08:47:06PM +0800, Jason Wang wrote: > > > On 2019/11/7 下午8:43, Jason Wang wrote: > > > > On 2019/11/7 下午7:21, Michael S. Tsirkin wrote: > > > > > On Thu, Nov 07, 2019 at 06:18:45PM +0800, Jason Wang wrote: > > > > > > On 2019/11/7 下午5:08, Michael S. Tsirkin wrote: > > > > > > > On Wed, Nov 06, 2019 at 09:35:31PM +0800, Jason Wang wrote: > > > > > > > > This sample driver creates mdev device that simulate > > > > > > > > virtio net device > > > > > > > > over virtio mdev transport. The device is implemented through vringh > > > > > > > > and workqueue. A device specific dma ops is to make sure HVA is used > > > > > > > > directly as the IOVA. This should be sufficient for kernel virtio > > > > > > > > driver to work. > > > > > > > > > > > > > > > > Only 'virtio' type is supported right now. I plan to add 'vhost' type > > > > > > > > on top which requires some virtual IOMMU implemented in this sample > > > > > > > > driver. > > > > > > > > > > > > > > > > Acked-by: Cornelia Huck<cohuck@redhat.com> > > > > > > > > Signed-off-by: Jason Wang<jasowang@redhat.com> > > > > > > > I'd prefer it that we call this something else, e.g. > > > > > > > mvnet-loopback. Just so people don't expect a fully > > > > > > > functional device somehow. Can be renamed when applying? > > > > > > Actually, I plan to extend it as another standard network interface for > > > > > > kernel. It could be either a standalone pseudo device or a stack > > > > > > device. > > > > > > Does this sounds good to you? > > > > > > > > > > > > Thanks > > > > > That's a big change in an interface so it's a good reason > > > > > to rename the driver at that point right? > > > > > Oherwise users of an old kernel would expect a stacked driver > > > > > and get a loopback instead. > > > > > > > > > > Or did I miss something? > > > > > > > > My understanding is that it was a sample driver in /doc. It should not > > > > be used in production environment. Otherwise we need to move it to > > > > driver/virtio. > > > > > > > > But if you insist, I can post a V11. > > > > > > > > Thanks > > > > > > Or maybe it's better to rename the type of current mdev from 'virtio' to > > > 'virtio-loopback'. Then we can add more types in the future. > > > > > > Thanks > > > > > Maybe but is virtio actually a loopback somehow? I thought we > > can bind a regular virtio device there, no? > > > It has a prefix, so user will see "mvnet-virtio-loopback". > > Thanks > yes but it's mvnet that is doing the loopback, not virtio
On 2019/11/7 下午9:50, Michael S. Tsirkin wrote: > On Thu, Nov 07, 2019 at 09:32:29PM +0800, Jason Wang wrote: >> On 2019/11/7 下午9:08, Michael S. Tsirkin wrote: >>> On Thu, Nov 07, 2019 at 08:43:29PM +0800, Jason Wang wrote: >>>> On 2019/11/7 下午7:21, Michael S. Tsirkin wrote: >>>>> On Thu, Nov 07, 2019 at 06:18:45PM +0800, Jason Wang wrote: >>>>>> On 2019/11/7 下午5:08, Michael S. Tsirkin wrote: >>>>>>> On Wed, Nov 06, 2019 at 09:35:31PM +0800, Jason Wang wrote: >>>>>>>> This sample driver creates mdev device that simulate virtio net device >>>>>>>> over virtio mdev transport. The device is implemented through vringh >>>>>>>> and workqueue. A device specific dma ops is to make sure HVA is used >>>>>>>> directly as the IOVA. This should be sufficient for kernel virtio >>>>>>>> driver to work. >>>>>>>> >>>>>>>> Only 'virtio' type is supported right now. I plan to add 'vhost' type >>>>>>>> on top which requires some virtual IOMMU implemented in this sample >>>>>>>> driver. >>>>>>>> >>>>>>>> Acked-by: Cornelia Huck<cohuck@redhat.com> >>>>>>>> Signed-off-by: Jason Wang<jasowang@redhat.com> >>>>>>> I'd prefer it that we call this something else, e.g. >>>>>>> mvnet-loopback. Just so people don't expect a fully >>>>>>> functional device somehow. Can be renamed when applying? >>>>>> Actually, I plan to extend it as another standard network interface for >>>>>> kernel. It could be either a standalone pseudo device or a stack device. >>>>>> Does this sounds good to you? >>>>>> >>>>>> Thanks >>>>> That's a big change in an interface so it's a good reason >>>>> to rename the driver at that point right? >>>>> Oherwise users of an old kernel would expect a stacked driver >>>>> and get a loopback instead. >>>>> >>>>> Or did I miss something? >>>> My understanding is that it was a sample driver in /doc. It should not be >>>> used in production environment. Otherwise we need to move it to >>>> driver/virtio. >>>> >>>> But if you insist, I can post a V11. >>>> >>>> Thanks >>> this can be a patch on top. >> Then maybe it's better just extend it to work as a normal networking device >> on top? >> >> Thanks > That would be a substantial change. Maybe drop 6/6 for now until > we have a better handle on this? > Ok, consider the change should be small, I will post V11 where I can fix the typos spotted. Thanks
diff --git a/MAINTAINERS b/MAINTAINERS index 4997957443df..6e9ad105a28f 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -17249,6 +17249,7 @@ F: include/uapi/linux/virtio_*.h F: drivers/crypto/virtio/ F: mm/balloon_compaction.c F: include/linux/mdev_virtio_ops.h +F: samples/vfio-mdev/mvnet.c VIRTIO BLOCK AND SCSI DRIVERS M: "Michael S. Tsirkin" <mst@redhat.com> diff --git a/samples/Kconfig b/samples/Kconfig index c8dacb4dda80..13a2443e18e0 100644 --- a/samples/Kconfig +++ b/samples/Kconfig @@ -131,6 +131,16 @@ config SAMPLE_VFIO_MDEV_MDPY mediated device. It is a simple framebuffer and supports the region display interface (VFIO_GFX_PLANE_TYPE_REGION). +config SAMPLE_VIRTIO_MDEV_NET + tristate "Build VIRTIO net example mediated device sample code -- loadable modules only" + depends on VIRTIO_MDEV && VHOST_RING && m + help + Build a networking sample device for use as a virtio + mediated device. The device coopreates with virtio-mdev bus + driver to present an virtio ethernet driver for + kernel. It simply loopbacks all packets from its TX + virtqueue to its RX virtqueue. + config SAMPLE_VFIO_MDEV_MDPY_FB tristate "Build VFIO mdpy example guest fbdev driver -- loadable module only" depends on FB && m diff --git a/samples/vfio-mdev/Makefile b/samples/vfio-mdev/Makefile index 10d179c4fdeb..f34af90ed0a0 100644 --- a/samples/vfio-mdev/Makefile +++ b/samples/vfio-mdev/Makefile @@ -3,3 +3,4 @@ obj-$(CONFIG_SAMPLE_VFIO_MDEV_MTTY) += mtty.o obj-$(CONFIG_SAMPLE_VFIO_MDEV_MDPY) += mdpy.o obj-$(CONFIG_SAMPLE_VFIO_MDEV_MDPY_FB) += mdpy-fb.o obj-$(CONFIG_SAMPLE_VFIO_MDEV_MBOCHS) += mbochs.o +obj-$(CONFIG_SAMPLE_VIRTIO_MDEV_NET) += mvnet.o diff --git a/samples/vfio-mdev/mvnet.c b/samples/vfio-mdev/mvnet.c new file mode 100644 index 000000000000..a89aecfab68a --- /dev/null +++ b/samples/vfio-mdev/mvnet.c @@ -0,0 +1,686 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Mediated virtual virtio-net device driver. + * + * Copyright (c) 2019, Red Hat Inc. All rights reserved. + * Author: Jason Wang <jasowang@redhat.com> + * + * Sample driver that creates mdev device that simulates ethernet loopback + * device. + * + * Usage: + * + * # modprobe virtio_mdev + * # modprobe mvnet + * # cd /sys/devices/virtual/mvnet/mvnet/mdev_supported_types/mvnet-virtio + * # echo "83b8f4f2-509f-382f-3c1e-e6bfe0fa1001" > ./create + * # cd devices/83b8f4f2-509f-382f-3c1e-e6bfe0fa1001 + * # ls -d virtio0 + * virtio0 + */ + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/device.h> +#include <linux/kernel.h> +#include <linux/fs.h> +#include <linux/poll.h> +#include <linux/slab.h> +#include <linux/sched.h> +#include <linux/wait.h> +#include <linux/uuid.h> +#include <linux/iommu.h> +#include <linux/sysfs.h> +#include <linux/file.h> +#include <linux/etherdevice.h> +#include <linux/mdev.h> +#include <linux/vringh.h> +#include <linux/mdev_virtio_ops.h> +#include <uapi/linux/virtio_config.h> +#include <uapi/linux/virtio_net.h> + +#define VERSION_STRING "0.1" +#define DRIVER_AUTHOR "Red Hat Corporation" + +#define MVNET_CLASS_NAME "mvnet" +#define MVNET_NAME "mvnet" + +/* + * Global Structures + */ + +static struct mvnet_dev { + struct class *vd_class; + struct idr vd_idr; + struct device dev; +} mvnet_dev; + +struct mvnet_virtqueue { + struct vringh vring; + struct vringh_kiov iov; + unsigned short head; + bool ready; + u64 desc_addr; + u64 device_addr; + u64 driver_addr; + u32 num; + void *private; + irqreturn_t (*cb)(void *data); +}; + +#define MVNET_QUEUE_ALIGN PAGE_SIZE +#define MVNET_QUEUE_MAX 256 +#define MVNET_DEVICE_ID 0x1 +#define MVNET_VENDOR_ID 0 + +u64 mvnet_features = (1ULL << VIRTIO_F_ANY_LAYOUT) | + (1ULL << VIRTIO_F_VERSION_1) | + (1ULL << VIRTIO_F_IOMMU_PLATFORM); + +/* State of each mdev device */ +struct mvnet_state { + struct mvnet_virtqueue vqs[2]; + struct work_struct work; + /* spinlock to synchronize virtqueue state */ + spinlock_t lock; + struct mdev_device *mdev; + struct virtio_net_config config; + void *buffer; + u32 status; + u32 generation; + u64 features; + struct list_head next; +}; + +static struct mutex mdev_list_lock; +static struct list_head mdev_devices_list; + +static void mvnet_queue_ready(struct mvnet_state *mvnet, unsigned int idx) +{ + struct mvnet_virtqueue *vq = &mvnet->vqs[idx]; + int ret; + + ret = vringh_init_kern(&vq->vring, mvnet_features, MVNET_QUEUE_MAX, + false, (struct vring_desc *)vq->desc_addr, + (struct vring_avail *)vq->driver_addr, + (struct vring_used *)vq->device_addr); +} + +static void mvnet_vq_reset(struct mvnet_virtqueue *vq) +{ + vq->ready = 0; + vq->desc_addr = 0; + vq->driver_addr = 0; + vq->device_addr = 0; + vq->cb = NULL; + vq->private = NULL; + vringh_init_kern(&vq->vring, mvnet_features, MVNET_QUEUE_MAX, + false, 0, 0, 0); +} + +static void mvnet_reset(struct mvnet_state *mvnet) +{ + int i; + + for (i = 0; i < 2; i++) + mvnet_vq_reset(&mvnet->vqs[i]); + + mvnet->features = 0; + mvnet->status = 0; + ++mvnet->generation; +} + +static void mvnet_work(struct work_struct *work) +{ + struct mvnet_state *mvnet = container_of(work, struct + mvnet_state, work); + struct mvnet_virtqueue *txq = &mvnet->vqs[1]; + struct mvnet_virtqueue *rxq = &mvnet->vqs[0]; + size_t read, write, total_write; + int err; + int pkts = 0; + + spin_lock(&mvnet->lock); + + if (!txq->ready || !rxq->ready) + goto out; + + while (true) { + total_write = 0; + err = vringh_getdesc_kern(&txq->vring, &txq->iov, NULL, + &txq->head, GFP_ATOMIC); + if (err <= 0) + break; + + err = vringh_getdesc_kern(&rxq->vring, NULL, &rxq->iov, + &rxq->head, GFP_ATOMIC); + if (err <= 0) { + vringh_complete_kern(&txq->vring, txq->head, 0); + break; + } + + while (true) { + read = vringh_iov_pull_kern(&txq->iov, mvnet->buffer, + PAGE_SIZE); + if (read <= 0) + break; + + write = vringh_iov_push_kern(&rxq->iov, mvnet->buffer, + read); + if (write <= 0) + break; + + total_write += write; + } + + /* Make sure data is wrote before advancing index */ + smp_wmb(); + + vringh_complete_kern(&txq->vring, txq->head, 0); + vringh_complete_kern(&rxq->vring, rxq->head, total_write); + + /* Make sure used is visible before rasing the interrupt. */ + smp_wmb(); + + local_bh_disable(); + if (txq->cb) + txq->cb(txq->private); + if (rxq->cb) + rxq->cb(rxq->private); + local_bh_enable(); + + if (++pkts > 4) { + schedule_work(&mvnet->work); + goto out; + } + } + +out: + spin_unlock(&mvnet->lock); +} + +static dma_addr_t mvnet_map_page(struct device *dev, struct page *page, + unsigned long offset, size_t size, + enum dma_data_direction dir, + unsigned long attrs) +{ + /* Vringh can only use HVA */ + return (dma_addr_t)(page_address(page) + offset); +} + +static void mvnet_unmap_page(struct device *dev, dma_addr_t dma_addr, + size_t size, enum dma_data_direction dir, + unsigned long attrs) +{ +} + +static void *mvnet_alloc_coherent(struct device *dev, size_t size, + dma_addr_t *dma_addr, gfp_t flag, + unsigned long attrs) +{ + void *addr = kmalloc(size, flag); + + if (!addr) + *dma_addr = DMA_MAPPING_ERROR; + else + *dma_addr = (dma_addr_t)addr; + + return addr; +} + +static void mvnet_free_coherent(struct device *dev, size_t size, + void *vaddr, dma_addr_t dma_addr, + unsigned long attrs) +{ + kfree((void *)dma_addr); +} + +static const struct dma_map_ops mvnet_dma_ops = { + .map_page = mvnet_map_page, + .unmap_page = mvnet_unmap_page, + .alloc = mvnet_alloc_coherent, + .free = mvnet_free_coherent, +}; + +static const struct mdev_virtio_device_ops mdev_virtio_ops; + +static int mvnet_create(struct kobject *kobj, struct mdev_device *mdev) +{ + struct mvnet_state *mvnet; + struct virtio_net_config *config; + struct device *dev = mdev_dev(mdev); + + if (!mdev) + return -EINVAL; + + mvnet = kzalloc(sizeof(*mvnet), GFP_KERNEL); + if (!mvnet) + return -ENOMEM; + + mvnet->buffer = kmalloc(PAGE_SIZE, GFP_KERNEL); + if (!mvnet->buffer) { + kfree(mvnet); + return -ENOMEM; + } + + config = &mvnet->config; + config->mtu = 1500; + config->status = VIRTIO_NET_S_LINK_UP; + eth_random_addr(config->mac); + + INIT_WORK(&mvnet->work, mvnet_work); + + spin_lock_init(&mvnet->lock); + mvnet->mdev = mdev; + mdev_set_drvdata(mdev, mvnet); + + mutex_lock(&mdev_list_lock); + list_add(&mvnet->next, &mdev_devices_list); + mutex_unlock(&mdev_list_lock); + + dev->coherent_dma_mask = DMA_BIT_MASK(64); + set_dma_ops(dev, &mvnet_dma_ops); + + mdev_set_virtio_ops(mdev, &mdev_virtio_ops); + + return 0; +} + +static int mvnet_remove(struct mdev_device *mdev) +{ + struct mvnet_state *mds, *tmp_mds; + struct mvnet_state *mvnet = mdev_get_drvdata(mdev); + int ret = -EINVAL; + + mutex_lock(&mdev_list_lock); + list_for_each_entry_safe(mds, tmp_mds, &mdev_devices_list, next) { + if (mvnet == mds) { + list_del(&mvnet->next); + mdev_set_drvdata(mdev, NULL); + kfree(mvnet->buffer); + kfree(mvnet); + ret = 0; + break; + } + } + mutex_unlock(&mdev_list_lock); + + return ret; +} + +static ssize_t +sample_mvnet_dev_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + if (mdev_from_dev(dev)) + return sprintf(buf, "This is MDEV %s\n", dev_name(dev)); + + return sprintf(buf, "\n"); +} + +static DEVICE_ATTR_RO(sample_mvnet_dev); + +static struct attribute *mvnet_dev_attrs[] = { + &dev_attr_sample_mvnet_dev.attr, + NULL, +}; + +static const struct attribute_group mvnet_dev_group = { + .name = "mvnet_dev", + .attrs = mvnet_dev_attrs, +}; + +static const struct attribute_group *mvnet_dev_groups[] = { + &mvnet_dev_group, + NULL, +}; + +static ssize_t +sample_mdev_dev_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + if (mdev_from_dev(dev)) + return sprintf(buf, "This is MDEV %s\n", dev_name(dev)); + + return sprintf(buf, "\n"); +} + +static DEVICE_ATTR_RO(sample_mdev_dev); + +static struct attribute *mdev_dev_attrs[] = { + &dev_attr_sample_mdev_dev.attr, + NULL, +}; + +static const struct attribute_group mdev_dev_group = { + .name = "vendor", + .attrs = mdev_dev_attrs, +}; + +static const struct attribute_group *mdev_dev_groups[] = { + &mdev_dev_group, + NULL, +}; + +#define MVNET_STRING_LEN 16 + +static ssize_t +name_show(struct kobject *kobj, struct device *dev, char *buf) +{ + char name[MVNET_STRING_LEN]; + const char *name_str = "virtio-net"; + + snprintf(name, MVNET_STRING_LEN, "%s", dev_driver_string(dev)); + if (!strcmp(kobj->name, name)) + return sprintf(buf, "%s\n", name_str); + + return -EINVAL; +} + +static MDEV_TYPE_ATTR_RO(name); + +static ssize_t +available_instances_show(struct kobject *kobj, struct device *dev, char *buf) +{ + return sprintf(buf, "%d\n", INT_MAX); +} + +static MDEV_TYPE_ATTR_RO(available_instances); + +static ssize_t device_api_show(struct kobject *kobj, struct device *dev, + char *buf) +{ + return sprintf(buf, "%s\n", VIRTIO_MDEV_DEVICE_API_STRING); +} + +static MDEV_TYPE_ATTR_RO(device_api); + +static struct attribute *mdev_types_attrs[] = { + &mdev_type_attr_name.attr, + &mdev_type_attr_device_api.attr, + &mdev_type_attr_available_instances.attr, + NULL, +}; + +static struct attribute_group mdev_type_group = { + .name = "virtio", + .attrs = mdev_types_attrs, +}; + +/* TBD: "vhost" type */ + +static struct attribute_group *mdev_type_groups[] = { + &mdev_type_group, + NULL, +}; + +static int mvnet_set_vq_address(struct mdev_device *mdev, u16 idx, + u64 desc_area, u64 driver_area, u64 device_area) +{ + struct mvnet_state *mvnet = mdev_get_drvdata(mdev); + struct mvnet_virtqueue *vq = &mvnet->vqs[idx]; + + vq->desc_addr = desc_area; + vq->driver_addr = driver_area; + vq->device_addr = device_area; + + return 0; +} + +static void mvnet_set_vq_num(struct mdev_device *mdev, u16 idx, u32 num) +{ + struct mvnet_state *mvnet = mdev_get_drvdata(mdev); + struct mvnet_virtqueue *vq = &mvnet->vqs[idx]; + + vq->num = num; +} + +static void mvnet_kick_vq(struct mdev_device *mdev, u16 idx) +{ + struct mvnet_state *mvnet = mdev_get_drvdata(mdev); + struct mvnet_virtqueue *vq = &mvnet->vqs[idx]; + + if (vq->ready) + schedule_work(&mvnet->work); +} + +static void mvnet_set_vq_cb(struct mdev_device *mdev, u16 idx, + struct virtio_mdev_callback *cb) +{ + struct mvnet_state *mvnet = mdev_get_drvdata(mdev); + struct mvnet_virtqueue *vq = &mvnet->vqs[idx]; + + vq->cb = cb->callback; + vq->private = cb->private; +} + +static void mvnet_set_vq_ready(struct mdev_device *mdev, u16 idx, bool ready) +{ + struct mvnet_state *mvnet = mdev_get_drvdata(mdev); + struct mvnet_virtqueue *vq = &mvnet->vqs[idx]; + + spin_lock(&mvnet->lock); + vq->ready = ready; + if (vq->ready) + mvnet_queue_ready(mvnet, idx); + spin_unlock(&mvnet->lock); +} + +static bool mvnet_get_vq_ready(struct mdev_device *mdev, u16 idx) +{ + struct mvnet_state *mvnet = mdev_get_drvdata(mdev); + struct mvnet_virtqueue *vq = &mvnet->vqs[idx]; + + return vq->ready; +} + +static int mvnet_set_vq_state(struct mdev_device *mdev, u16 idx, u64 state) +{ + struct mvnet_state *mvnet = mdev_get_drvdata(mdev); + struct mvnet_virtqueue *vq = &mvnet->vqs[idx]; + struct vringh *vrh = &vq->vring; + + spin_lock(&mvnet->lock); + vrh->last_avail_idx = state; + spin_unlock(&mvnet->lock); + + return 0; +} + +static u64 mvnet_get_vq_state(struct mdev_device *mdev, u16 idx) +{ + struct mvnet_state *mvnet = mdev_get_drvdata(mdev); + struct mvnet_virtqueue *vq = &mvnet->vqs[idx]; + struct vringh *vrh = &vq->vring; + + return vrh->last_avail_idx; +} + +static u16 mvnet_get_vq_align(struct mdev_device *mdev) +{ + return MVNET_QUEUE_ALIGN; +} + +static u64 mvnet_get_features(struct mdev_device *mdev) +{ + return mvnet_features; +} + +static int mvnet_set_features(struct mdev_device *mdev, u64 features) +{ + struct mvnet_state *mvnet = mdev_get_drvdata(mdev); + + /* DMA mapping must be done by driver */ + if (!(features & (1ULL << VIRTIO_F_IOMMU_PLATFORM))) + return -EINVAL; + + mvnet->features = features & mvnet_features; + + return 0; +} + +static void mvnet_set_config_cb(struct mdev_device *mdev, + struct virtio_mdev_callback *cb) +{ + /* We don't support config interrupt */ +} + +static u16 mvnet_get_vq_num_max(struct mdev_device *mdev) +{ + return MVNET_QUEUE_MAX; +} + +static u32 mvnet_get_device_id(struct mdev_device *mdev) +{ + return MVNET_DEVICE_ID; +} + +static u32 mvnet_get_vendor_id(struct mdev_device *mdev) +{ + return MVNET_VENDOR_ID; +} + +static u8 mvnet_get_status(struct mdev_device *mdev) +{ + struct mvnet_state *mvnet = mdev_get_drvdata(mdev); + + return mvnet->status; +} + +static void mvnet_set_status(struct mdev_device *mdev, u8 status) +{ + struct mvnet_state *mvnet = mdev_get_drvdata(mdev); + + mvnet->status = status; + + if (status == 0) { + spin_lock(&mvnet->lock); + mvnet_reset(mvnet); + spin_unlock(&mvnet->lock); + } +} + +static void mvnet_get_config(struct mdev_device *mdev, unsigned int offset, + void *buf, unsigned int len) +{ + struct mvnet_state *mvnet = mdev_get_drvdata(mdev); + + if (offset + len < sizeof(struct virtio_net_config)) + memcpy(buf, &mvnet->config + offset, len); +} + +static void mvnet_set_config(struct mdev_device *mdev, unsigned int offset, + const void *buf, unsigned int len) +{ + /* No writable config supportted by mvnet */ +} + +static u32 mvnet_get_generation(struct mdev_device *mdev) +{ + struct mvnet_state *mvnet = mdev_get_drvdata(mdev); + + return mvnet->generation; +} + +static const struct mdev_virtio_device_ops mdev_virtio_ops = { + .set_vq_address = mvnet_set_vq_address, + .set_vq_num = mvnet_set_vq_num, + .kick_vq = mvnet_kick_vq, + .set_vq_cb = mvnet_set_vq_cb, + .set_vq_ready = mvnet_set_vq_ready, + .get_vq_ready = mvnet_get_vq_ready, + .set_vq_state = mvnet_set_vq_state, + .get_vq_state = mvnet_get_vq_state, + .get_vq_align = mvnet_get_vq_align, + .get_features = mvnet_get_features, + .set_features = mvnet_set_features, + .set_config_cb = mvnet_set_config_cb, + .get_vq_num_max = mvnet_get_vq_num_max, + .get_device_id = mvnet_get_device_id, + .get_vendor_id = mvnet_get_vendor_id, + .get_status = mvnet_get_status, + .set_status = mvnet_set_status, + .get_config = mvnet_get_config, + .set_config = mvnet_set_config, + .get_generation = mvnet_get_generation, +}; + +static const struct mdev_parent_ops mdev_fops = { + .owner = THIS_MODULE, + .dev_attr_groups = mvnet_dev_groups, + .mdev_attr_groups = mdev_dev_groups, + .supported_type_groups = mdev_type_groups, + .create = mvnet_create, + .remove = mvnet_remove, +}; + +static void mvnet_device_release(struct device *dev) +{ + dev_dbg(dev, "mvnet: released\n"); +} + +static int __init mvnet_dev_init(void) +{ + int ret = 0; + + pr_info("mvnet_dev: %s\n", __func__); + + memset(&mvnet_dev, 0, sizeof(mvnet_dev)); + + idr_init(&mvnet_dev.vd_idr); + + mvnet_dev.vd_class = class_create(THIS_MODULE, MVNET_CLASS_NAME); + + if (IS_ERR(mvnet_dev.vd_class)) { + pr_err("Error: failed to register mvnet_dev class\n"); + ret = PTR_ERR(mvnet_dev.vd_class); + goto failed1; + } + + mvnet_dev.dev.class = mvnet_dev.vd_class; + mvnet_dev.dev.release = mvnet_device_release; + dev_set_name(&mvnet_dev.dev, "%s", MVNET_NAME); + + ret = device_register(&mvnet_dev.dev); + if (ret) + goto failed2; + + ret = mdev_register_device(&mvnet_dev.dev, &mdev_fops); + if (ret) + goto failed3; + + mutex_init(&mdev_list_lock); + INIT_LIST_HEAD(&mdev_devices_list); + + goto all_done; + +failed3: + + device_unregister(&mvnet_dev.dev); +failed2: + class_destroy(mvnet_dev.vd_class); + +failed1: +all_done: + return ret; +} + +static void __exit mvnet_dev_exit(void) +{ + mvnet_dev.dev.bus = NULL; + mdev_unregister_device(&mvnet_dev.dev); + + device_unregister(&mvnet_dev.dev); + idr_destroy(&mvnet_dev.vd_idr); + class_destroy(mvnet_dev.vd_class); + mvnet_dev.vd_class = NULL; + pr_info("mvnet_dev: Unloaded!\n"); +} + +module_init(mvnet_dev_init) +module_exit(mvnet_dev_exit) + +MODULE_LICENSE("GPL v2"); +MODULE_INFO(supported, "Simulate loopback ethernet device over mdev"); +MODULE_VERSION(VERSION_STRING); +MODULE_AUTHOR(DRIVER_AUTHOR);