From 0c853c2c2924464bd86537164ed18d5d953b4909 Mon Sep 17 00:00:00 2001 From: Max Gurtovoy Date: Mon, 15 Mar 2021 17:34:47 +0100 Subject: vdpa: add vdpa simulator for block device This will allow running vDPA for virtio block protocol. It's a preliminary implementation with a simple request handling: for each request, only the status (last byte) is set. It's always set to VIRTIO_BLK_S_OK. Also input validation is missing and will be added in the next commits. Signed-off-by: Max Gurtovoy [sgarzare: various cleanups/fixes] Acked-by: Jason Wang Signed-off-by: Stefano Garzarella Link: https://lore.kernel.org/r/20210315163450.254396-12-sgarzare@redhat.com Signed-off-by: Michael S. Tsirkin --- drivers/vdpa/vdpa_sim/Makefile | 1 + drivers/vdpa/vdpa_sim/vdpa_sim_blk.c | 145 +++++++++++++++++++++++++++++++++++ 2 files changed, 146 insertions(+) create mode 100644 drivers/vdpa/vdpa_sim/vdpa_sim_blk.c (limited to 'drivers/vdpa/vdpa_sim') diff --git a/drivers/vdpa/vdpa_sim/Makefile b/drivers/vdpa/vdpa_sim/Makefile index 79d4536d347e..d458103302f2 100644 --- a/drivers/vdpa/vdpa_sim/Makefile +++ b/drivers/vdpa/vdpa_sim/Makefile @@ -1,3 +1,4 @@ # SPDX-License-Identifier: GPL-2.0 obj-$(CONFIG_VDPA_SIM) += vdpa_sim.o obj-$(CONFIG_VDPA_SIM_NET) += vdpa_sim_net.o +obj-$(CONFIG_VDPA_SIM_BLOCK) += vdpa_sim_blk.o diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c b/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c new file mode 100644 index 000000000000..64926a70af5e --- /dev/null +++ b/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c @@ -0,0 +1,145 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * VDPA simulator for block device. + * + * Copyright (c) 2020, NVIDIA CORPORATION. All rights reserved. + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "vdpa_sim.h" + +#define DRV_VERSION "0.1" +#define DRV_AUTHOR "Max Gurtovoy " +#define DRV_DESC "vDPA Device Simulator for block device" +#define DRV_LICENSE "GPL v2" + +#define VDPASIM_BLK_FEATURES (VDPASIM_FEATURES | \ + (1ULL << VIRTIO_BLK_F_SIZE_MAX) | \ + (1ULL << VIRTIO_BLK_F_SEG_MAX) | \ + (1ULL << VIRTIO_BLK_F_BLK_SIZE) | \ + (1ULL << VIRTIO_BLK_F_TOPOLOGY) | \ + (1ULL << VIRTIO_BLK_F_MQ)) + +#define VDPASIM_BLK_CAPACITY 0x40000 +#define VDPASIM_BLK_SIZE_MAX 0x1000 +#define VDPASIM_BLK_SEG_MAX 32 +#define VDPASIM_BLK_VQ_NUM 1 + +static struct vdpasim *vdpasim_blk_dev; + +static void vdpasim_blk_work(struct work_struct *work) +{ + struct vdpasim *vdpasim = container_of(work, struct vdpasim, work); + u8 status = VIRTIO_BLK_S_OK; + int i; + + spin_lock(&vdpasim->lock); + + if (!(vdpasim->status & VIRTIO_CONFIG_S_DRIVER_OK)) + goto out; + + for (i = 0; i < VDPASIM_BLK_VQ_NUM; i++) { + struct vdpasim_virtqueue *vq = &vdpasim->vqs[i]; + + if (!vq->ready) + continue; + + while (vringh_getdesc_iotlb(&vq->vring, &vq->out_iov, + &vq->in_iov, &vq->head, + GFP_ATOMIC) > 0) { + int write; + + vq->in_iov.i = vq->in_iov.used - 1; + write = vringh_iov_push_iotlb(&vq->vring, &vq->in_iov, + &status, 1); + if (write <= 0) + break; + + /* Make sure data is wrote before advancing index */ + smp_wmb(); + + vringh_complete_iotlb(&vq->vring, vq->head, write); + + /* Make sure used is visible before rasing the interrupt. */ + smp_wmb(); + + local_bh_disable(); + if (vringh_need_notify_iotlb(&vq->vring) > 0) + vringh_notify(&vq->vring); + local_bh_enable(); + } + } +out: + spin_unlock(&vdpasim->lock); +} + +static void vdpasim_blk_get_config(struct vdpasim *vdpasim, void *config) +{ + struct virtio_blk_config *blk_config = config; + + memset(config, 0, sizeof(struct virtio_blk_config)); + + blk_config->capacity = cpu_to_vdpasim64(vdpasim, VDPASIM_BLK_CAPACITY); + blk_config->size_max = cpu_to_vdpasim32(vdpasim, VDPASIM_BLK_SIZE_MAX); + blk_config->seg_max = cpu_to_vdpasim32(vdpasim, VDPASIM_BLK_SEG_MAX); + blk_config->num_queues = cpu_to_vdpasim16(vdpasim, VDPASIM_BLK_VQ_NUM); + blk_config->min_io_size = cpu_to_vdpasim16(vdpasim, 1); + blk_config->opt_io_size = cpu_to_vdpasim32(vdpasim, 1); + blk_config->blk_size = cpu_to_vdpasim32(vdpasim, SECTOR_SIZE); +} + +static int __init vdpasim_blk_init(void) +{ + struct vdpasim_dev_attr dev_attr = {}; + int ret; + + dev_attr.id = VIRTIO_ID_BLOCK; + dev_attr.supported_features = VDPASIM_BLK_FEATURES; + dev_attr.nvqs = VDPASIM_BLK_VQ_NUM; + dev_attr.config_size = sizeof(struct virtio_blk_config); + dev_attr.get_config = vdpasim_blk_get_config; + dev_attr.work_fn = vdpasim_blk_work; + dev_attr.buffer_size = PAGE_SIZE; + + vdpasim_blk_dev = vdpasim_create(&dev_attr); + if (IS_ERR(vdpasim_blk_dev)) { + ret = PTR_ERR(vdpasim_blk_dev); + goto out; + } + + ret = vdpa_register_device(&vdpasim_blk_dev->vdpa, VDPASIM_BLK_VQ_NUM); + if (ret) + goto put_dev; + + return 0; + +put_dev: + put_device(&vdpasim_blk_dev->vdpa.dev); +out: + return ret; +} + +static void __exit vdpasim_blk_exit(void) +{ + struct vdpa_device *vdpa = &vdpasim_blk_dev->vdpa; + + vdpa_unregister_device(vdpa); +} + +module_init(vdpasim_blk_init) +module_exit(vdpasim_blk_exit) + +MODULE_VERSION(DRV_VERSION); +MODULE_LICENSE(DRV_LICENSE); +MODULE_AUTHOR(DRV_AUTHOR); +MODULE_DESCRIPTION(DRV_DESC); -- cgit