On Fri, Jun 28, 2024 at 04:57:08PM +0200, Albert Esteve wrote: > Add a cache BAR in the vhost-user-device > into which files can be directly mapped. > > The number, shmid, and size of the VIRTIO Shared > Memory subregions is retrieved through a get_shmem_config > message sent by the vhost-user-base module > on the realize step, after virtio_init(). > > By default, if VHOST_USER_PROTOCOL_F_SHMEM > feature is not supported by the backend, > there is no cache. > > Signed-off-by: Albert Esteve <aest...@redhat.com>
Michael: Please review vhost_user_device_pci_realize() below regarding
virtio-pci BAR layout. Thanks!
> ---
> hw/virtio/vhost-user-base.c | 39 +++++++++++++++++++++++++++++--
> hw/virtio/vhost-user-device-pci.c | 37 ++++++++++++++++++++++++++---
> 2 files changed, 71 insertions(+), 5 deletions(-)
>
> diff --git a/hw/virtio/vhost-user-base.c b/hw/virtio/vhost-user-base.c
> index a83167191e..e47c568a55 100644
> --- a/hw/virtio/vhost-user-base.c
> +++ b/hw/virtio/vhost-user-base.c
> @@ -268,7 +268,9 @@ static void vub_device_realize(DeviceState *dev, Error
> **errp)
> {
> VirtIODevice *vdev = VIRTIO_DEVICE(dev);
> VHostUserBase *vub = VHOST_USER_BASE(dev);
> - int ret;
> + uint64_t memory_sizes[8];
> + void *cache_ptr;
> + int i, ret, nregions;
>
> if (!vub->chardev.chr) {
> error_setg(errp, "vhost-user-base: missing chardev");
> @@ -311,7 +313,7 @@ static void vub_device_realize(DeviceState *dev, Error
> **errp)
>
> /* Allocate queues */
> vub->vqs = g_ptr_array_sized_new(vub->num_vqs);
> - for (int i = 0; i < vub->num_vqs; i++) {
> + for (i = 0; i < vub->num_vqs; i++) {
> g_ptr_array_add(vub->vqs,
> virtio_add_queue(vdev, vub->vq_size,
> vub_handle_output));
> @@ -328,6 +330,39 @@ static void vub_device_realize(DeviceState *dev, Error
> **errp)
> do_vhost_user_cleanup(vdev, vub);
> }
>
> + ret = vub->vhost_dev.vhost_ops->vhost_get_shmem_config(&vub->vhost_dev,
> + &nregions,
> + memory_sizes,
> + errp);
> +
> + if (ret < 0) {
> + do_vhost_user_cleanup(vdev, vub);
> + }
> +
> + for (i = 0; i < nregions; i++) {
> + if (memory_sizes[i]) {
> + if (!is_power_of_2(memory_sizes[i]) ||
> + memory_sizes[i] < qemu_real_host_page_size()) {
Or just if (memory_sizes[i] % qemu_real_host_page_size() != 0)?
> + error_setg(errp, "Shared memory %d size must be a power of 2
> "
> + "no smaller than the page size", i);
> + return;
> + }
> +
> + cache_ptr = mmap(NULL, memory_sizes[i], PROT_READ,
Should this be PROT_NONE like in
vhost_user_backend_handle_shmem_unmap()?
> + MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
> + if (cache_ptr == MAP_FAILED) {
> + error_setg(errp, "Unable to mmap blank cache: %s",
> + strerror(errno));
error_setg_errno() can be used here.
> + return;
> + }
> +
> + virtio_new_shmem_region(vdev);
> + memory_region_init_ram_ptr(&vdev->shmem_list[i],
> + OBJECT(vdev), "vub-shm-" + i,
> + memory_sizes[i], cache_ptr);
> + }
> + }
> +
> qemu_chr_fe_set_handlers(&vub->chardev, NULL, NULL, vub_event, NULL,
> dev, NULL, true);
> }
> diff --git a/hw/virtio/vhost-user-device-pci.c
> b/hw/virtio/vhost-user-device-pci.c
> index efaf55d3dd..314bacfb7a 100644
> --- a/hw/virtio/vhost-user-device-pci.c
> +++ b/hw/virtio/vhost-user-device-pci.c
> @@ -8,14 +8,18 @@
> */
>
> #include "qemu/osdep.h"
> +#include "qapi/error.h"
> #include "hw/qdev-properties.h"
> #include "hw/virtio/vhost-user-base.h"
> #include "hw/virtio/virtio-pci.h"
>
> +#define VIRTIO_DEVICE_PCI_CACHE_BAR 2
> +
> struct VHostUserDevicePCI {
> VirtIOPCIProxy parent_obj;
>
> VHostUserBase vub;
> + MemoryRegion cachebar;
> };
>
> #define TYPE_VHOST_USER_DEVICE_PCI "vhost-user-device-pci-base"
> @@ -25,10 +29,37 @@ OBJECT_DECLARE_SIMPLE_TYPE(VHostUserDevicePCI,
> VHOST_USER_DEVICE_PCI)
> static void vhost_user_device_pci_realize(VirtIOPCIProxy *vpci_dev, Error
> **errp)
> {
> VHostUserDevicePCI *dev = VHOST_USER_DEVICE_PCI(vpci_dev);
> - DeviceState *vdev = DEVICE(&dev->vub);
> -
> + DeviceState *dev_state = DEVICE(&dev->vub);
> + VirtIODevice *vdev = VIRTIO_DEVICE(dev_state);
> + uint64_t offset = 0, cache_size = 0;
> + int i;
> +
> vpci_dev->nvectors = 1;
> - qdev_realize(vdev, BUS(&vpci_dev->bus), errp);
> + qdev_realize(dev_state, BUS(&vpci_dev->bus), errp);
> +
> + for (i = 0; i < vdev->n_shmem_regions; i++) {
> + if (vdev->shmem_list[i].size > UINT64_MAX - cache_size) {
> + error_setg(errp, "Total shared memory required overflow");
> + return;
> + }
> + cache_size = cache_size + vdev->shmem_list[i].size;
> + }
> + if (cache_size) {
> + memory_region_init(&dev->cachebar, OBJECT(vpci_dev),
> + "vhost-device-pci-cachebar", cache_size);
> + for (i = 0; i < vdev->n_shmem_regions; i++) {
> + memory_region_add_subregion(&dev->cachebar, offset,
> + &vdev->shmem_list[i]);
> + virtio_pci_add_shm_cap(vpci_dev, VIRTIO_DEVICE_PCI_CACHE_BAR,
> + offset, vdev->shmem_list[i].size, i);
> + offset = offset + vdev->shmem_list[i].size;
> + }
> + pci_register_bar(&vpci_dev->pci_dev, VIRTIO_DEVICE_PCI_CACHE_BAR,
> + PCI_BASE_ADDRESS_SPACE_MEMORY |
> + PCI_BASE_ADDRESS_MEM_PREFETCH |
> + PCI_BASE_ADDRESS_MEM_TYPE_64,
> + &dev->cachebar);
> + }
> }
>
> static void vhost_user_device_pci_class_init(ObjectClass *klass, void *data)
> --
> 2.45.2
>
signature.asc
Description: PGP signature
