diff options
Diffstat (limited to 'drivers/vdpa/vdpa_user/vduse_dev.c')
| -rw-r--r-- | drivers/vdpa/vdpa_user/vduse_dev.c | 1641 |
1 files changed, 1641 insertions, 0 deletions
diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c new file mode 100644 index 000000000000..29a38ecba19e --- /dev/null +++ b/drivers/vdpa/vdpa_user/vduse_dev.c @@ -0,0 +1,1641 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * VDUSE: vDPA Device in Userspace + * + * Copyright (C) 2020-2021 Bytedance Inc. and/or its affiliates. All rights reserved. + * + * Author: Xie Yongji <xieyongji@bytedance.com> + * + */ + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/cdev.h> +#include <linux/device.h> +#include <linux/eventfd.h> +#include <linux/slab.h> +#include <linux/wait.h> +#include <linux/dma-map-ops.h> +#include <linux/poll.h> +#include <linux/file.h> +#include <linux/uio.h> +#include <linux/vdpa.h> +#include <linux/nospec.h> +#include <uapi/linux/vduse.h> +#include <uapi/linux/vdpa.h> +#include <uapi/linux/virtio_config.h> +#include <uapi/linux/virtio_ids.h> +#include <uapi/linux/virtio_blk.h> +#include <linux/mod_devicetable.h> + +#include "iova_domain.h" + +#define DRV_AUTHOR "Yongji Xie <xieyongji@bytedance.com>" +#define DRV_DESC "vDPA Device in Userspace" +#define DRV_LICENSE "GPL v2" + +#define VDUSE_DEV_MAX (1U << MINORBITS) +#define VDUSE_BOUNCE_SIZE (64 * 1024 * 1024) +#define VDUSE_IOVA_SIZE (128 * 1024 * 1024) +#define VDUSE_MSG_DEFAULT_TIMEOUT 30 + +struct vduse_virtqueue { + u16 index; + u16 num_max; + u32 num; + u64 desc_addr; + u64 driver_addr; + u64 device_addr; + struct vdpa_vq_state state; + bool ready; + bool kicked; + spinlock_t kick_lock; + spinlock_t irq_lock; + struct eventfd_ctx *kickfd; + struct vdpa_callback cb; + struct work_struct inject; + struct work_struct kick; +}; + +struct vduse_dev; + +struct vduse_vdpa { + struct vdpa_device vdpa; + struct vduse_dev *dev; +}; + +struct vduse_dev { + struct vduse_vdpa *vdev; + struct device *dev; + struct vduse_virtqueue *vqs; + struct vduse_iova_domain *domain; + char *name; + struct mutex lock; + spinlock_t msg_lock; + u64 msg_unique; + u32 msg_timeout; + wait_queue_head_t waitq; + struct list_head send_list; + struct list_head recv_list; + struct vdpa_callback config_cb; + struct work_struct inject; + spinlock_t irq_lock; + int minor; + bool broken; + bool connected; + u64 api_version; + u64 device_features; + u64 driver_features; + u32 device_id; + u32 vendor_id; + u32 generation; + u32 config_size; + void *config; + u8 status; + u32 vq_num; + u32 vq_align; +}; + +struct vduse_dev_msg { + struct vduse_dev_request req; + struct vduse_dev_response resp; + struct list_head list; + wait_queue_head_t waitq; + bool completed; +}; + +struct vduse_control { + u64 api_version; +}; + +static DEFINE_MUTEX(vduse_lock); +static DEFINE_IDR(vduse_idr); + +static dev_t vduse_major; +static struct class *vduse_class; +static struct cdev vduse_ctrl_cdev; +static struct cdev vduse_cdev; +static struct workqueue_struct *vduse_irq_wq; + +static u32 allowed_device_id[] = { + VIRTIO_ID_BLOCK, +}; + +static inline struct vduse_dev *vdpa_to_vduse(struct vdpa_device *vdpa) +{ + struct vduse_vdpa *vdev = container_of(vdpa, struct vduse_vdpa, vdpa); + + return vdev->dev; +} + +static inline struct vduse_dev *dev_to_vduse(struct device *dev) +{ + struct vdpa_device *vdpa = dev_to_vdpa(dev); + + return vdpa_to_vduse(vdpa); +} + +static struct vduse_dev_msg *vduse_find_msg(struct list_head *head, + uint32_t request_id) +{ + struct vduse_dev_msg *msg; + + list_for_each_entry(msg, head, list) { + if (msg->req.request_id == request_id) { + list_del(&msg->list); + return msg; + } + } + + return NULL; +} + +static struct vduse_dev_msg *vduse_dequeue_msg(struct list_head *head) +{ + struct vduse_dev_msg *msg = NULL; + + if (!list_empty(head)) { + msg = list_first_entry(head, struct vduse_dev_msg, list); + list_del(&msg->list); + } + + return msg; +} + +static void vduse_enqueue_msg(struct list_head *head, + struct vduse_dev_msg *msg) +{ + list_add_tail(&msg->list, head); +} + +static void vduse_dev_broken(struct vduse_dev *dev) +{ + struct vduse_dev_msg *msg, *tmp; + + if (unlikely(dev->broken)) + return; + + list_splice_init(&dev->recv_list, &dev->send_list); + list_for_each_entry_safe(msg, tmp, &dev->send_list, list) { + list_del(&msg->list); + msg->completed = 1; + msg->resp.result = VDUSE_REQ_RESULT_FAILED; + wake_up(&msg->waitq); + } + dev->broken = true; + wake_up(&dev->waitq); +} + +static int vduse_dev_msg_sync(struct vduse_dev *dev, + struct vduse_dev_msg *msg) +{ + int ret; + + if (unlikely(dev->broken)) + return -EIO; + + init_waitqueue_head(&msg->waitq); + spin_lock(&dev->msg_lock); + if (unlikely(dev->broken)) { + spin_unlock(&dev->msg_lock); + return -EIO; + } + msg->req.request_id = dev->msg_unique++; + vduse_enqueue_msg(&dev->send_list, msg); + wake_up(&dev->waitq); + spin_unlock(&dev->msg_lock); + if (dev->msg_timeout) + ret = wait_event_killable_timeout(msg->waitq, msg->completed, + (long)dev->msg_timeout * HZ); + else + ret = wait_event_killable(msg->waitq, msg->completed); + + spin_lock(&dev->msg_lock); + if (!msg->completed) { + list_del(&msg->list); + msg->resp.result = VDUSE_REQ_RESULT_FAILED; + /* Mark the device as malfunction when there is a timeout */ + if (!ret) + vduse_dev_broken(dev); + } + ret = (msg->resp.result == VDUSE_REQ_RESULT_OK) ? 0 : -EIO; + spin_unlock(&dev->msg_lock); + + return ret; +} + +static int vduse_dev_get_vq_state_packed(struct vduse_dev *dev, + struct vduse_virtqueue *vq, + struct vdpa_vq_state_packed *packed) +{ + struct vduse_dev_msg msg = { 0 }; + int ret; + + msg.req.type = VDUSE_GET_VQ_STATE; + msg.req.vq_state.index = vq->index; + + ret = vduse_dev_msg_sync(dev, &msg); + if (ret) + return ret; + + packed->last_avail_counter = + msg.resp.vq_state.packed.last_avail_counter & 0x0001; + packed->last_avail_idx = + msg.resp.vq_state.packed.last_avail_idx & 0x7FFF; + packed->last_used_counter = + msg.resp.vq_state.packed.last_used_counter & 0x0001; + packed->last_used_idx = + msg.resp.vq_state.packed.last_used_idx & 0x7FFF; + + return 0; +} + +static int vduse_dev_get_vq_state_split(struct vduse_dev *dev, + struct vduse_virtqueue *vq, + struct vdpa_vq_state_split *split) +{ + struct vduse_dev_msg msg = { 0 }; + int ret; + + msg.req.type = VDUSE_GET_VQ_STATE; + msg.req.vq_state.index = vq->index; + + ret = vduse_dev_msg_sync(dev, &msg); + if (ret) + return ret; + + split->avail_index = msg.resp.vq_state.split.avail_index; + + return 0; +} + +static int vduse_dev_set_status(struct vduse_dev *dev, u8 status) +{ + struct vduse_dev_msg msg = { 0 }; + + msg.req.type = VDUSE_SET_STATUS; + msg.req.s.status = status; + + return vduse_dev_msg_sync(dev, &msg); +} + +static int vduse_dev_update_iotlb(struct vduse_dev *dev, + u64 start, u64 last) +{ + struct vduse_dev_msg msg = { 0 }; + + if (last < start) + return -EINVAL; + + msg.req.type = VDUSE_UPDATE_IOTLB; + msg.req.iova.start = start; + msg.req.iova.last = last; + + return vduse_dev_msg_sync(dev, &msg); +} + +static ssize_t vduse_dev_read_iter(struct kiocb *iocb, struct iov_iter *to) +{ + struct file *file = iocb->ki_filp; + struct vduse_dev *dev = file->private_data; + struct vduse_dev_msg *msg; + int size = sizeof(struct vduse_dev_request); + ssize_t ret; + + if (iov_iter_count(to) < size) + return -EINVAL; + + spin_lock(&dev->msg_lock); + while (1) { + msg = vduse_dequeue_msg(&dev->send_list); + if (msg) + break; + + ret = -EAGAIN; + if (file->f_flags & O_NONBLOCK) + goto unlock; + + spin_unlock(&dev->msg_lock); + ret = wait_event_interruptible_exclusive(dev->waitq, + !list_empty(&dev->send_list)); + if (ret) + return ret; + + spin_lock(&dev->msg_lock); + } + spin_unlock(&dev->msg_lock); + ret = copy_to_iter(&msg->req, size, to); + spin_lock(&dev->msg_lock); + if (ret != size) { + ret = -EFAULT; + vduse_enqueue_msg(&dev->send_list, msg); + goto unlock; + } + vduse_enqueue_msg(&dev->recv_list, msg); +unlock: + spin_unlock(&dev->msg_lock); + + return ret; +} + +static bool is_mem_zero(const char *ptr, int size) +{ + int i; + + for (i = 0; i < size; i++) { + if (ptr[i]) + return false; + } + return true; +} + +static ssize_t vduse_dev_write_iter(struct kiocb *iocb, struct iov_iter *from) +{ + struct file *file = iocb->ki_filp; + struct vduse_dev *dev = file->private_data; + struct vduse_dev_response resp; + struct vduse_dev_msg *msg; + size_t ret; + + ret = copy_from_iter(&resp, sizeof(resp), from); + if (ret != sizeof(resp)) + return -EINVAL; + + if (!is_mem_zero((const char *)resp.reserved, sizeof(resp.reserved))) + return -EINVAL; + + spin_lock(&dev->msg_lock); + msg = vduse_find_msg(&dev->recv_list, resp.request_id); + if (!msg) { + ret = -ENOENT; + goto unlock; + } + + memcpy(&msg->resp, &resp, sizeof(resp)); + msg->completed = 1; + wake_up(&msg->waitq); +unlock: + spin_unlock(&dev->msg_lock); + + return ret; +} + +static __poll_t vduse_dev_poll(struct file *file, poll_table *wait) +{ + struct vduse_dev *dev = file->private_data; + __poll_t mask = 0; + + poll_wait(file, &dev->waitq, wait); + + spin_lock(&dev->msg_lock); + + if (unlikely(dev->broken)) + mask |= EPOLLERR; + if (!list_empty(&dev->send_list)) + mask |= EPOLLIN | EPOLLRDNORM; + if (!list_empty(&dev->recv_list)) + mask |= EPOLLOUT | EPOLLWRNORM; + + spin_unlock(&dev->msg_lock); + + return mask; +} + +static void vduse_dev_reset(struct vduse_dev *dev) +{ + int i; + struct vduse_iova_domain *domain = dev->domain; + + /* The coherent mappings are handled in vduse_dev_free_coherent() */ + if (domain->bounce_map) + vduse_domain_reset_bounce_map(domain); + + dev->status = 0; + dev->driver_features = 0; + dev->generation++; + spin_lock(&dev->irq_lock); + dev->config_cb.callback = NULL; + dev->config_cb.private = NULL; + spin_unlock(&dev->irq_lock); + flush_work(&dev->inject); + + for (i = 0; i < dev->vq_num; i++) { + struct vduse_virtqueue *vq = &dev->vqs[i]; + + vq->ready = false; + vq->desc_addr = 0; + vq->driver_addr = 0; + vq->device_addr = 0; + vq->num = 0; + memset(&vq->state, 0, sizeof(vq->state)); + + spin_lock(&vq->kick_lock); + vq->kicked = false; + if (vq->kickfd) + eventfd_ctx_put(vq->kickfd); + vq->kickfd = NULL; + spin_unlock(&vq->kick_lock); + + spin_lock(&vq->irq_lock); + vq->cb.callback = NULL; + vq->cb.private = NULL; + spin_unlock(&vq->irq_lock); + flush_work(&vq->inject); + flush_work(&vq->kick); + } +} + +static int vduse_vdpa_set_vq_address(struct vdpa_device *vdpa, u16 idx, + u64 desc_area, u64 driver_area, + u64 device_area) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + struct vduse_virtqueue *vq = &dev->vqs[idx]; + + vq->desc_addr = desc_area; + vq->driver_addr = driver_area; + vq->device_addr = device_area; + + return 0; +} + +static void vduse_vq_kick(struct vduse_virtqueue *vq) +{ + spin_lock(&vq->kick_lock); + if (!vq->ready) + goto unlock; + + if (vq->kickfd) + eventfd_signal(vq->kickfd, 1); + else + vq->kicked = true; +unlock: + spin_unlock(&vq->kick_lock); +} + +static void vduse_vq_kick_work(struct work_struct *work) +{ + struct vduse_virtqueue *vq = container_of(work, + struct vduse_virtqueue, kick); + + vduse_vq_kick(vq); +} + +static void vduse_vdpa_kick_vq(struct vdpa_device *vdpa, u16 idx) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + struct vduse_virtqueue *vq = &dev->vqs[idx]; + + if (!eventfd_signal_allowed()) { + schedule_work(&vq->kick); + return; + } + vduse_vq_kick(vq); +} + +static void vduse_vdpa_set_vq_cb(struct vdpa_device *vdpa, u16 idx, + struct vdpa_callback *cb) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + struct vduse_virtqueue *vq = &dev->vqs[idx]; + + spin_lock(&vq->irq_lock); + vq->cb.callback = cb->callback; + vq->cb.private = cb->private; + spin_unlock(&vq->irq_lock); +} + +static void vduse_vdpa_set_vq_num(struct vdpa_device *vdpa, u16 idx, u32 num) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + struct vduse_virtqueue *vq = &dev->vqs[idx]; + + vq->num = num; +} + +static void vduse_vdpa_set_vq_ready(struct vdpa_device *vdpa, + u16 idx, bool ready) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + struct vduse_virtqueue *vq = &dev->vqs[idx]; + + vq->ready = ready; +} + +static bool vduse_vdpa_get_vq_ready(struct vdpa_device *vdpa, u16 idx) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + struct vduse_virtqueue *vq = &dev->vqs[idx]; + + return vq->ready; +} + +static int vduse_vdpa_set_vq_state(struct vdpa_device *vdpa, u16 idx, + const struct vdpa_vq_state *state) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + struct vduse_virtqueue *vq = &dev->vqs[idx]; + + if (dev->driver_features & BIT_ULL(VIRTIO_F_RING_PACKED)) { + vq->state.packed.last_avail_counter = + state->packed.last_avail_counter; + vq->state.packed.last_avail_idx = state->packed.last_avail_idx; + vq->state.packed.last_used_counter = + state->packed.last_used_counter; + vq->state.packed.last_used_idx = state->packed.last_used_idx; + } else + vq->state.split.avail_index = state->split.avail_index; + + return 0; +} + +static int vduse_vdpa_get_vq_state(struct vdpa_device *vdpa, u16 idx, + struct vdpa_vq_state *state) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + struct vduse_virtqueue *vq = &dev->vqs[idx]; + + if (dev->driver_features & BIT_ULL(VIRTIO_F_RING_PACKED)) + return vduse_dev_get_vq_state_packed(dev, vq, &state->packed); + + return vduse_dev_get_vq_state_split(dev, vq, &state->split); +} + +static u32 vduse_vdpa_get_vq_align(struct vdpa_device *vdpa) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + + return dev->vq_align; +} + +static u64 vduse_vdpa_get_features(struct vdpa_device *vdpa) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + + return dev->device_features; +} + +static int vduse_vdpa_set_features(struct vdpa_device *vdpa, u64 features) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + + dev->driver_features = features; + return 0; +} + +static void vduse_vdpa_set_config_cb(struct vdpa_device *vdpa, + struct vdpa_callback *cb) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + + spin_lock(&dev->irq_lock); + dev->config_cb.callback = cb->callback; + dev->config_cb.private = cb->private; + spin_unlock(&dev->irq_lock); +} + +static u16 vduse_vdpa_get_vq_num_max(struct vdpa_device *vdpa) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + u16 num_max = 0; + int i; + + for (i = 0; i < dev->vq_num; i++) + if (num_max < dev->vqs[i].num_max) + num_max = dev->vqs[i].num_max; + + return num_max; +} + +static u32 vduse_vdpa_get_device_id(struct vdpa_device *vdpa) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + + return dev->device_id; +} + +static u32 vduse_vdpa_get_vendor_id(struct vdpa_device *vdpa) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + + return dev->vendor_id; +} + +static u8 vduse_vdpa_get_status(struct vdpa_device *vdpa) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + + return dev->status; +} + +static void vduse_vdpa_set_status(struct vdpa_device *vdpa, u8 status) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + + if (vduse_dev_set_status(dev, status)) + return; + + dev->status = status; +} + +static size_t vduse_vdpa_get_config_size(struct vdpa_device *vdpa) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + + return dev->config_size; +} + +static void vduse_vdpa_get_config(struct vdpa_device *vdpa, unsigned int offset, + void *buf, unsigned int len) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + + if (len > dev->config_size - offset) + return; + + memcpy(buf, dev->config + offset, len); +} + +static void vduse_vdpa_set_config(struct vdpa_device *vdpa, unsigned int offset, + const void *buf, unsigned int len) +{ + /* Now we only support read-only configuration space */ +} + +static int vduse_vdpa_reset(struct vdpa_device *vdpa) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + + if (vduse_dev_set_status(dev, 0)) + return -EIO; + + vduse_dev_reset(dev); + + return 0; +} + +static u32 vduse_vdpa_get_generation(struct vdpa_device *vdpa) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + + return dev->generation; +} + +static int vduse_vdpa_set_map(struct vdpa_device *vdpa, + struct vhost_iotlb *iotlb) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + int ret; + + ret = vduse_domain_set_map(dev->domain, iotlb); + if (ret) + return ret; + + ret = vduse_dev_update_iotlb(dev, 0ULL, ULLONG_MAX); + if (ret) { + vduse_domain_clear_map(dev->domain, iotlb); + return ret; + } + + return 0; +} + +static void vduse_vdpa_free(struct vdpa_device *vdpa) +{ + struct vduse_dev *dev = vdpa_to_vduse(vdpa); + + dev->vdev = NULL; +} + +static const struct vdpa_config_ops vduse_vdpa_config_ops = { + .set_vq_address = vduse_vdpa_set_vq_address, + .kick_vq = vduse_vdpa_kick_vq, + .set_vq_cb = vduse_vdpa_set_vq_cb, + .set_vq_num = vduse_vdpa_set_vq_num, + .set_vq_ready = vduse_vdpa_set_vq_ready, + .get_vq_ready = vduse_vdpa_get_vq_ready, + .set_vq_state = vduse_vdpa_set_vq_state, + .get_vq_state = vduse_vdpa_get_vq_state, + .get_vq_align = vduse_vdpa_get_vq_align, + .get_features = vduse_vdpa_get_features, + .set_features = vduse_vdpa_set_features, + .set_config_cb = vduse_vdpa_set_config_cb, + .get_vq_num_max = vduse_vdpa_get_vq_num_max, + .get_device_id = vduse_vdpa_get_device_id, + .get_vendor_id = vduse_vdpa_get_vendor_id, + .get_status = vduse_vdpa_get_status, + .set_status = vduse_vdpa_set_status, + .get_config_size = vduse_vdpa_get_config_size, + .get_config = vduse_vdpa_get_config, + .set_config = vduse_vdpa_set_config, + .get_generation = vduse_vdpa_get_generation, + .reset = vduse_vdpa_reset, + .set_map = vduse_vdpa_set_map, + .free = vduse_vdpa_free, +}; + +static dma_addr_t vduse_dev_map_page(struct device *dev, struct page *page, + unsigned long offset, size_t size, + enum dma_data_direction dir, + unsigned long attrs) +{ + struct vduse_dev *vdev = dev_to_vduse(dev); + struct vduse_iova_domain *domain = vdev->domain; + + return vduse_domain_map_page(domain, page, offset, size, dir, attrs); +} + +static void vduse_dev_unmap_page(struct device *dev, dma_addr_t dma_addr, + size_t size, enum dma_data_direction dir, + unsigned long attrs) +{ + struct vduse_dev *vdev = dev_to_vduse(dev); + struct vduse_iova_domain *domain = vdev->domain; + + return vduse_domain_unmap_page(domain, dma_addr, size, dir, attrs); +} + +static void *vduse_dev_alloc_coherent(struct device *dev, size_t size, + dma_addr_t *dma_addr, gfp_t flag, + unsigned long attrs) +{ + struct vduse_dev *vdev = dev_to_vduse(dev); + struct vduse_iova_domain *domain = vdev->domain; + unsigned long iova; + void *addr; + + *dma_addr = DMA_MAPPING_ERROR; + addr = vduse_domain_alloc_coherent(domain, size, + (dma_addr_t *)&iova, flag, attrs); + if (!addr) + return NULL; + + *dma_addr = (dma_addr_t)iova; + + return addr; +} + +static void vduse_dev_free_coherent(struct device *dev, size_t size, + void *vaddr, dma_addr_t dma_addr, + unsigned long attrs) +{ + struct vduse_dev *vdev = dev_to_vduse(dev); + struct vduse_iova_domain *domain = vdev->domain; + + vduse_domain_free_coherent(domain, size, vaddr, dma_addr, attrs); +} + +static size_t vduse_dev_max_mapping_size(struct device *dev) +{ + struct vduse_dev *vdev = dev_to_vduse(dev); + struct vduse_iova_domain *domain = vdev->domain; + + return domain->bounce_size; +} + +static const struct dma_map_ops vduse_dev_dma_ops = { + .map_page = vduse_dev_map_page, + .unmap_page = vduse_dev_unmap_page, + .alloc = vduse_dev_alloc_coherent, + .free = vduse_dev_free_coherent, + .max_mapping_size = vduse_dev_max_mapping_size, +}; + +static unsigned int perm_to_file_flags(u8 perm) +{ + unsigned int flags = 0; + + switch (perm) { + case VDUSE_ACCESS_WO: + flags |= O_WRONLY; + break; + case VDUSE_ACCESS_RO: + flags |= O_RDONLY; + break; + case VDUSE_ACCESS_RW: + flags |= O_RDWR; + break; + default: + WARN(1, "invalidate vhost IOTLB permission\n"); + break; + } + + return flags; +} + +static int vduse_kickfd_setup(struct vduse_dev *dev, + struct vduse_vq_eventfd *eventfd) +{ + struct eventfd_ctx *ctx = NULL; + struct vduse_virtqueue *vq; + u32 index; + + if (eventfd->index >= dev->vq_num) + return -EINVAL; + + index = array_index_nospec(eventfd->index, dev->vq_num); + vq = &dev->vqs[index]; + if (eventfd->fd >= 0) { + ctx = eventfd_ctx_fdget(eventfd->fd); + if (IS_ERR(ctx)) + return PTR_ERR(ctx); + } else if (eventfd->fd != VDUSE_EVENTFD_DEASSIGN) + return 0; + + spin_lock(&vq->kick_lock); + if (vq->kickfd) + eventfd_ctx_put(vq->kickfd); + vq->kickfd = ctx; + if (vq->ready && vq->kicked && vq->kickfd) { + eventfd_signal(vq->kickfd, 1); + vq->kicked = false; + } + spin_unlock(&vq->kick_lock); + + return 0; +} + +static bool vduse_dev_is_ready(struct vduse_dev *dev) +{ + int i; + + for (i = 0; i < dev->vq_num; i++) + if (!dev->vqs[i].num_max) + return false; + + return true; +} + +static void vduse_dev_irq_inject(struct work_struct *work) +{ + struct vduse_dev *dev = container_of(work, struct vduse_dev, inject); + + spin_lock_irq(&dev->irq_lock); + if (dev->config_cb.callback) + dev->config_cb.callback(dev->config_cb.private); + spin_unlock_irq(&dev->irq_lock); +} + +static void vduse_vq_irq_inject(struct work_struct *work) +{ + struct vduse_virtqueue *vq = container_of(work, + struct vduse_virtqueue, inject); + + spin_lock_irq(&vq->irq_lock); + if (vq->ready && vq->cb.callback) + vq->cb.callback(vq->cb.private); + spin_unlock_irq(&vq->irq_lock); +} + +static long vduse_dev_ioctl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + struct vduse_dev *dev = file->private_data; + void __user *argp = (void __user *)arg; + int ret; + + if (unlikely(dev->broken)) + return -EPERM; + + switch (cmd) { + case VDUSE_IOTLB_GET_FD: { + struct vduse_iotlb_entry entry; + struct vhost_iotlb_map *map; + struct vdpa_map_file *map_file; + struct vduse_iova_domain *domain = dev->domain; + struct file *f = NULL; + + ret = -EFAULT; + if (copy_from_user(&entry, argp, sizeof(entry))) + break; + + ret = -EINVAL; + if (entry.start > entry.last) + break; + + spin_lock(&domain->iotlb_lock); + map = vhost_iotlb_itree_first(domain->iotlb, + entry.start, entry.last); + if (map) { + map_file = (struct vdpa_map_file *)map->opaque; + f = get_file(map_file->file); + entry.offset = map_file->offset; + entry.start = map->start; + entry.last = map->last; + entry.perm = map->perm; + } + spin_unlock(&domain->iotlb_lock); + ret = -EINVAL; + if (!f) + break; + + ret = -EFAULT; + if (copy_to_user(argp, &entry, sizeof(entry))) { + fput(f); + break; + } + ret = receive_fd(f, perm_to_file_flags(entry.perm)); + fput(f); + break; + } + case VDUSE_DEV_GET_FEATURES: + /* + * Just mirror what driver wrote here. + * The driver is expected to check FEATURE_OK later. + */ + ret = put_user(dev->driver_features, (u64 __user *)argp); + break; + case VDUSE_DEV_SET_CONFIG: { + struct vduse_config_data config; + unsigned long size = offsetof(struct vduse_config_data, + buffer); + + ret = -EFAULT; + if (copy_from_user(&config, argp, size)) + break; + + ret = -EINVAL; + if (config.length == 0 || + config.length > dev->config_size - config.offset) + break; + + ret = -EFAULT; + if (copy_from_user(dev->config + config.offset, argp + size, + config.length)) + break; + + ret = 0; + break; + } + case VDUSE_DEV_INJECT_CONFIG_IRQ: + ret = 0; + queue_work(vduse_irq_wq, &dev->inject); + break; + case VDUSE_VQ_SETUP: { + struct vduse_vq_config config; + u32 index; + + ret = -EFAULT; + if (copy_from_user(&config, argp, sizeof(config))) + break; + + ret = -EINVAL; + if (config.index >= dev->vq_num) + break; + + if (!is_mem_zero((const char *)config.reserved, + sizeof(config.reserved))) + break; + + index = array_index_nospec(config.index, dev->vq_num); + dev->vqs[index].num_max = config.max_size; + ret = 0; + break; + } + case VDUSE_VQ_GET_INFO: { + struct vduse_vq_info vq_info; + struct vduse_virtqueue *vq; + u32 index; + + ret = -EFAULT; + if (copy_from_user(&vq_info, argp, sizeof(vq_info))) + break; + + ret = -EINVAL; + if (vq_info.index >= dev->vq_num) + break; + + index = array_index_nospec(vq_info.index, dev->vq_num); + vq = &dev->vqs[index]; + vq_info.desc_addr = vq->desc_addr; + vq_info.driver_addr = vq->driver_addr; + vq_info.device_addr = vq->device_addr; + vq_info.num = vq->num; + + if (dev->driver_features & BIT_ULL(VIRTIO_F_RING_PACKED)) { + vq_info.packed.last_avail_counter = + vq->state.packed.last_avail_counter; + vq_info.packed.last_avail_idx = + vq->state.packed.last_avail_idx; + vq_info.packed.last_used_counter = + vq->state.packed.last_used_counter; + vq_info.packed.last_used_idx = + vq->state.packed.last_used_idx; + } else + vq_info.split.avail_index = + vq->state.split.avail_index; + + vq_info.ready = vq->ready; + + ret = -EFAULT; + if (copy_to_user(argp, &vq_info, sizeof(vq_info))) + break; + + ret = 0; + break; + } + case VDUSE_VQ_SETUP_KICKFD: { + struct vduse_vq_eventfd eventfd; + + ret = -EFAULT; + if (copy_from_user(&eventfd, argp, sizeof(eventfd))) + break; + + ret = vduse_kickfd_setup(dev, &eventfd); + break; + } + case VDUSE_VQ_INJECT_IRQ: { + u32 index; + + ret = -EFAULT; + if (get_user(index, (u32 __user *)argp)) + break; + + ret = -EINVAL; + if (index >= dev->vq_num) + break; + + ret = 0; + index = array_index_nospec(index, dev->vq_num); + queue_work(vduse_irq_wq, &dev->vqs[index].inject); + break; + } + default: + ret = -ENOIOCTLCMD; + break; + } + + return ret; +} + +static int vduse_dev_release(struct inode *inode, struct file *file) +{ + struct vduse_dev *dev = file->private_data; + + spin_lock(&dev->msg_lock); + /* Make sure the inflight messages can processed after reconncection */ + list_splice_init(&dev->recv_list, &dev->send_list); + spin_unlock(&dev->msg_lock); + dev->connected = false; + + return 0; +} + +static struct vduse_dev *vduse_dev_get_from_minor(int minor) +{ + struct vduse_dev *dev; + + mutex_lock(&vduse_lock); + dev = idr_find(&vduse_idr, minor); + mutex_unlock(&vduse_lock); + + return dev; +} + +static int vduse_dev_open(struct inode *inode, struct file *file) +{ + int ret; + struct vduse_dev *dev = vduse_dev_get_from_minor(iminor(inode)); + + if (!dev) + return -ENODEV; + + ret = -EBUSY; + mutex_lock(&dev->lock); + if (dev->connected) + goto unlock; + + ret = 0; + dev->connected = true; + file->private_data = dev; +unlock: + mutex_unlock(&dev->lock); + + return ret; +} + +static const struct file_operations vduse_dev_fops = { + .owner = THIS_MODULE, + .open = vduse_dev_open, + .release = vduse_dev_release, + .read_iter = vduse_dev_read_iter, + .write_iter = vduse_dev_write_iter, + .poll = vduse_dev_poll, + .unlocked_ioctl = vduse_dev_ioctl, + .compat_ioctl = compat_ptr_ioctl, + .llseek = noop_llseek, +}; + +static struct vduse_dev *vduse_dev_create(void) +{ + struct vduse_dev *dev = kzalloc(sizeof(*dev), GFP_KERNEL); + + if (!dev) + return NULL; + + mutex_init(&dev->lock); + spin_lock_init(&dev->msg_lock); + INIT_LIST_HEAD(&dev->send_list); + INIT_LIST_HEAD(&dev->recv_list); + spin_lock_init(&dev->irq_lock); + + INIT_WORK(&dev->inject, vduse_dev_irq_inject); + init_waitqueue_head(&dev->waitq); + + return dev; +} + +static void vduse_dev_destroy(struct vduse_dev *dev) +{ + kfree(dev); +} + +static struct vduse_dev *vduse_find_dev(const char *name) +{ + struct vduse_dev *dev; + int id; + + idr_for_each_entry(&vduse_idr, dev, id) + if (!strcmp(dev->name, name)) + return dev; + + return NULL; +} + +static int vduse_destroy_dev(char *name) +{ + struct vduse_dev *dev = vduse_find_dev(name); + + if (!dev) + return -EINVAL; + + mutex_lock(&dev->lock); + if (dev->vdev || dev->connected) { + mutex_unlock(&dev->lock); + return -EBUSY; + } + dev->connected = true; + mutex_unlock(&dev->lock); + + vduse_dev_reset(dev); + device_destroy(vduse_class, MKDEV(MAJOR(vduse_major), dev->minor)); + idr_remove(&vduse_idr, dev->minor); + kvfree(dev->config); + kfree(dev->vqs); + vduse_domain_destroy(dev->domain); + kfree(dev->name); + vduse_dev_destroy(dev); + module_put(THIS_MODULE); + + return 0; +} + +static bool device_is_allowed(u32 device_id) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(allowed_device_id); i++) + if (allowed_device_id[i] == device_id) + return true; + + return false; +} + +static bool features_is_valid(u64 features) +{ + if (!(features & (1ULL << VIRTIO_F_ACCESS_PLATFORM))) + return false; + + /* Now we only support read-only configuration space */ + if (features & (1ULL << VIRTIO_BLK_F_CONFIG_WCE)) + return false; + + return true; +} + +static bool vduse_validate_config(struct vduse_dev_config *config) +{ + if (!is_mem_zero((const char *)config->reserved, + sizeof(config->reserved))) + return false; + + if (config->vq_align > PAGE_SIZE) + return false; + + if (config->config_size > PAGE_SIZE) + return false; + + if (!device_is_allowed(config->device_id)) + return false; + + if (!features_is_valid(config->features)) + return false; + + return true; +} + +static ssize_t msg_timeout_show(struct device *device, + struct device_attribute *attr, char *buf) +{ + struct vduse_dev *dev = dev_get_drvdata(device); + + return sysfs_emit(buf, "%u\n", dev->msg_timeout); +} + +static ssize_t msg_timeout_store(struct device *device, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct vduse_dev *dev = dev_get_drvdata(device); + int ret; + + ret = kstrtouint(buf, 10, &dev->msg_timeout); + if (ret < 0) + return ret; + + return count; +} + +static DEVICE_ATTR_RW(msg_timeout); + +static struct attribute *vduse_dev_attrs[] = { + &dev_attr_msg_timeout.attr, + NULL +}; + +ATTRIBUTE_GROUPS(vduse_dev); + +static int vduse_create_dev(struct vduse_dev_config *config, + void *config_buf, u64 api_version) +{ + int i, ret; + struct vduse_dev *dev; + + ret = -EEXIST; + if (vduse_find_dev(config->name)) + goto err; + + ret = -ENOMEM; + dev = vduse_dev_create(); + if (!dev) + goto err; + + dev->api_version = api_version; + dev->device_features = config->features; + dev->device_id = config->device_id; + dev->vendor_id = config->vendor_id; + dev->name = kstrdup(config->name, GFP_KERNEL); + if (!dev->name) + goto err_str; + + dev->domain = vduse_domain_create(VDUSE_IOVA_SIZE - 1, + VDUSE_BOUNCE_SIZE); + if (!dev->domain) + goto err_domain; + + dev->config = config_buf; + dev->config_size = config->config_size; + dev->vq_align = config->vq_align; + dev->vq_num = config->vq_num; + dev->vqs = kcalloc(dev->vq_num, sizeof(*dev->vqs), GFP_KERNEL); + if (!dev->vqs) + goto err_vqs; + + for (i = 0; i < dev->vq_num; i++) { + dev->vqs[i].index = i; + INIT_WORK(&dev->vqs[i].inject, vduse_vq_irq_inject); + INIT_WORK(&dev->vqs[i].kick, vduse_vq_kick_work); + spin_lock_init(&dev->vqs[i].kick_lock); + spin_lock_init(&dev->vqs[i].irq_lock); + } + + ret = idr_alloc(&vduse_idr, dev, 1, VDUSE_DEV_MAX, GFP_KERNEL); + if (ret < 0) + goto err_idr; + + dev->minor = ret; + dev->msg_timeout = VDUSE_MSG_DEFAULT_TIMEOUT; + dev->dev = device_create(vduse_class, NULL, + MKDEV(MAJOR(vduse_major), dev->minor), + dev, "%s", config->name); + if (IS_ERR(dev->dev)) { + ret = PTR_ERR(dev->dev); + goto err_dev; + } + __module_get(THIS_MODULE); + + return 0; +err_dev: + idr_remove(&vduse_idr, dev->minor); +err_idr: + kfree(dev->vqs); +err_vqs: + vduse_domain_destroy(dev->domain); +err_domain: + kfree(dev->name); +err_str: + vduse_dev_destroy(dev); +err: + kvfree(config_buf); + return ret; +} + +static long vduse_ioctl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + int ret; + void __user *argp = (void __user *)arg; + struct vduse_control *control = file->private_data; + + mutex_lock(&vduse_lock); + switch (cmd) { + case VDUSE_GET_API_VERSION: + ret = put_user(control->api_version, (u64 __user *)argp); + break; + case VDUSE_SET_API_VERSION: { + u64 api_version; + + ret = -EFAULT; + if (get_user(api_version, (u64 __user *)argp)) + break; + + ret = -EINVAL; + if (api_version > VDUSE_API_VERSION) + break; + + ret = 0; + control->api_version = api_version; + break; + } + case VDUSE_CREATE_DEV: { + struct vduse_dev_config config; + unsigned long size = offsetof(struct vduse_dev_config, config); + void *buf; + + ret = -EFAULT; + if (copy_from_user(&config, argp, size)) + break; + + ret = -EINVAL; + if (vduse_validate_config(&config) == false) + break; + + buf = vmemdup_user(argp + size, config.config_size); + if (IS_ERR(buf)) { + ret = PTR_ERR(buf); + break; + } + config.name[VDUSE_NAME_MAX - 1] = '\0'; + ret = vduse_create_dev(&config, buf, control->api_version); + break; + } + case VDUSE_DESTROY_DEV: { + char name[VDUSE_NAME_MAX]; + + ret = -EFAULT; + if (copy_from_user(name, argp, VDUSE_NAME_MAX)) + break; + + name[VDUSE_NAME_MAX - 1] = '\0'; + ret = vduse_destroy_dev(name); + break; + } + default: + ret = -EINVAL; + break; + } + mutex_unlock(&vduse_lock); + + return ret; +} + +static int vduse_release(struct inode *inode, struct file *file) +{ + struct vduse_control *control = file->private_data; + + kfree(control); + return 0; +} + +static int vduse_open(struct inode *inode, struct file *file) +{ + struct vduse_control *control; + + control = kmalloc(sizeof(struct vduse_control), GFP_KERNEL); + if (!control) + return -ENOMEM; + + control->api_version = VDUSE_API_VERSION; + file->private_data = control; + + return 0; +} + +static const struct file_operations vduse_ctrl_fops = { + .owner = THIS_MODULE, + .open = vduse_open, + .release = vduse_release, + .unlocked_ioctl = vduse_ioctl, + .compat_ioctl = compat_ptr_ioctl, + .llseek = noop_llseek, +}; + +static char *vduse_devnode(struct device *dev, umode_t *mode) +{ + return kasprintf(GFP_KERNEL, "vduse/%s", dev_name(dev)); +} + +static void vduse_mgmtdev_release(struct device *dev) +{ +} + +static struct device vduse_mgmtdev = { + .init_name = "vduse", + .release = vduse_mgmtdev_release, +}; + +static struct vdpa_mgmt_dev mgmt_dev; + +static int vduse_dev_init_vdpa(struct vduse_dev *dev, const char *name) +{ + struct vduse_vdpa *vdev; + int ret; + + if (dev->vdev) + return -EEXIST; + + vdev = vdpa_alloc_device(struct vduse_vdpa, vdpa, dev->dev, + &vduse_vdpa_config_ops, name, true); + if (IS_ERR(vdev)) + return PTR_ERR(vdev); + + dev->vdev = vdev; + vdev->dev = dev; + vdev->vdpa.dev.dma_mask = &vdev->vdpa.dev.coherent_dma_mask; + ret = dma_set_mask_and_coherent(&vdev->vdpa.dev, DMA_BIT_MASK(64)); + if (ret) { + put_device(&vdev->vdpa.dev); + return ret; + } + set_dma_ops(&vdev->vdpa.dev, &vduse_dev_dma_ops); + vdev->vdpa.dma_dev = &vdev->vdpa.dev; + vdev->vdpa.mdev = &mgmt_dev; + + return 0; +} + +static int vdpa_dev_add(struct vdpa_mgmt_dev *mdev, const char *name) +{ + struct vduse_dev *dev; + int ret; + + mutex_lock(&vduse_lock); + dev = vduse_find_dev(name); + if (!dev || !vduse_dev_is_ready(dev)) { + mutex_unlock(&vduse_lock); + return -EINVAL; + } + ret = vduse_dev_init_vdpa(dev, name); + mutex_unlock(&vduse_lock); + if (ret) + return ret; + + ret = _vdpa_register_device(&dev->vdev->vdpa, dev->vq_num); + if (ret) { + put_device(&dev->vdev->vdpa.dev); + return ret; + } + + return 0; +} + +static void vdpa_dev_del(struct vdpa_mgmt_dev *mdev, struct vdpa_device *dev) +{ + _vdpa_unregister_device(dev); +} + +static const struct vdpa_mgmtdev_ops vdpa_dev_mgmtdev_ops = { + .dev_add = vdpa_dev_add, + .dev_del = vdpa_dev_del, +}; + +static struct virtio_device_id id_table[] = { + { VIRTIO_ID_BLOCK, VIRTIO_DEV_ANY_ID }, + { 0 }, +}; + +static struct vdpa_mgmt_dev mgmt_dev = { + .device = &vduse_mgmtdev, + .id_table = id_table, + .ops = &vdpa_dev_mgmtdev_ops, +}; + +static int vduse_mgmtdev_init(void) +{ + int ret; + + ret = device_register(&vduse_mgmtdev); + if (ret) + return ret; + + ret = vdpa_mgmtdev_register(&mgmt_dev); + if (ret) + goto err; + + return 0; +err: + device_unregister(&vduse_mgmtdev); + return ret; +} + +static void vduse_mgmtdev_exit(void) +{ + vdpa_mgmtdev_unregister(&mgmt_dev); + device_unregister(&vduse_mgmtdev); +} + +static int vduse_init(void) +{ + int ret; + struct device *dev; + + vduse_class = class_create(THIS_MODULE, "vduse"); + if (IS_ERR(vduse_class)) + return PTR_ERR(vduse_class); + + vduse_class->devnode = vduse_devnode; + vduse_class->dev_groups = vduse_dev_groups; + + ret = alloc_chrdev_region(&vduse_major, 0, VDUSE_DEV_MAX, "vduse"); + if (ret) + goto err_chardev_region; + + /* /dev/vduse/control */ + cdev_init(&vduse_ctrl_cdev, &vduse_ctrl_fops); + vduse_ctrl_cdev.owner = THIS_MODULE; + ret = cdev_add(&vduse_ctrl_cdev, vduse_major, 1); + if (ret) + goto err_ctrl_cdev; + + dev = device_create(vduse_class, NULL, vduse_major, NULL, "control"); + if (IS_ERR(dev)) { + ret = PTR_ERR(dev); + goto err_device; + } + + /* /dev/vduse/$DEVICE */ + cdev_init(&vduse_cdev, &vduse_dev_fops); + vduse_cdev.owner = THIS_MODULE; + ret = cdev_add(&vduse_cdev, MKDEV(MAJOR(vduse_major), 1), + VDUSE_DEV_MAX - 1); + if (ret) + goto err_cdev; + + vduse_irq_wq = alloc_workqueue("vduse-irq", + WQ_HIGHPRI | WQ_SYSFS | WQ_UNBOUND, 0); + if (!vduse_irq_wq) + goto err_wq; + + ret = vduse_domain_init(); + if (ret) + goto err_domain; + + ret = vduse_mgmtdev_init(); + if (ret) + goto err_mgmtdev; + + return 0; +err_mgmtdev: + vduse_domain_exit(); +err_domain: + destroy_workqueue(vduse_irq_wq); +err_wq: + cdev_del(&vduse_cdev); +err_cdev: + device_destroy(vduse_class, vduse_major); +err_device: + cdev_del(&vduse_ctrl_cdev); +err_ctrl_cdev: + unregister_chrdev_region(vduse_major, VDUSE_DEV_MAX); +err_chardev_region: + class_destroy(vduse_class); + return ret; +} +module_init(vduse_init); + +static void vduse_exit(void) +{ + vduse_mgmtdev_exit(); + vduse_domain_exit(); + destroy_workqueue(vduse_irq_wq); + cdev_del(&vduse_cdev); + device_destroy(vduse_class, vduse_major); + cdev_del(&vduse_ctrl_cdev); + unregister_chrdev_region(vduse_major, VDUSE_DEV_MAX); + class_destroy(vduse_class); +} +module_exit(vduse_exit); + +MODULE_LICENSE(DRV_LICENSE); +MODULE_AUTHOR(DRV_AUTHOR); +MODULE_DESCRIPTION(DRV_DESC); |