diff options
Diffstat (limited to 'drivers/vhost/vdpa.c')
| -rw-r--r-- | drivers/vhost/vdpa.c | 116 |
1 files changed, 113 insertions, 3 deletions
diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c index 0968361e3b77..7580e34f76c1 100644 --- a/drivers/vhost/vdpa.c +++ b/drivers/vhost/vdpa.c @@ -15,12 +15,14 @@ #include <linux/module.h> #include <linux/cdev.h> #include <linux/device.h> +#include <linux/mm.h> #include <linux/iommu.h> #include <linux/uuid.h> #include <linux/vdpa.h> #include <linux/nospec.h> #include <linux/vhost.h> #include <linux/virtio_net.h> +#include <linux/kernel.h> #include "vhost.h" @@ -70,6 +72,7 @@ struct vhost_vdpa { int nvqs; int virtio_id; int minor; + struct eventfd_ctx *config_ctx; }; static DEFINE_IDA(vhost_vdpa_ida); @@ -101,6 +104,17 @@ static irqreturn_t vhost_vdpa_virtqueue_cb(void *private) return IRQ_HANDLED; } +static irqreturn_t vhost_vdpa_config_cb(void *private) +{ + struct vhost_vdpa *v = private; + struct eventfd_ctx *config_ctx = v->config_ctx; + + if (config_ctx) + eventfd_signal(config_ctx, 1); + + return IRQ_HANDLED; +} + static void vhost_vdpa_reset(struct vhost_vdpa *v) { struct vdpa_device *vdpa = v->vdpa; @@ -288,6 +302,36 @@ static long vhost_vdpa_get_vring_num(struct vhost_vdpa *v, u16 __user *argp) return 0; } +static void vhost_vdpa_config_put(struct vhost_vdpa *v) +{ + if (v->config_ctx) + eventfd_ctx_put(v->config_ctx); +} + +static long vhost_vdpa_set_config_call(struct vhost_vdpa *v, u32 __user *argp) +{ + struct vdpa_callback cb; + int fd; + struct eventfd_ctx *ctx; + + cb.callback = vhost_vdpa_config_cb; + cb.private = v->vdpa; + if (copy_from_user(&fd, argp, sizeof(fd))) + return -EFAULT; + + ctx = fd == VHOST_FILE_UNBIND ? NULL : eventfd_ctx_fdget(fd); + swap(ctx, v->config_ctx); + + if (!IS_ERR_OR_NULL(ctx)) + eventfd_ctx_put(ctx); + + if (IS_ERR(v->config_ctx)) + return PTR_ERR(v->config_ctx); + + v->vdpa->config->set_config_cb(v->vdpa, &cb); + + return 0; +} static long vhost_vdpa_vring_ioctl(struct vhost_vdpa *v, unsigned int cmd, void __user *argp) { @@ -395,6 +439,9 @@ static long vhost_vdpa_unlocked_ioctl(struct file *filep, case VHOST_SET_LOG_FD: r = -ENOIOCTLCMD; break; + case VHOST_VDPA_SET_CONFIG_CALL: + r = vhost_vdpa_set_config_call(v, argp); + break; default: r = vhost_dev_ioctl(&v->vdev, cmd, argp); if (r == -ENOIOCTLCMD) @@ -527,7 +574,7 @@ static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v, if (!npages) return -EINVAL; - down_read(&dev->mm->mmap_sem); + mmap_read_lock(dev->mm); locked = atomic64_add_return(npages, &dev->mm->pinned_vm); lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; @@ -580,7 +627,7 @@ out: vhost_vdpa_unmap(v, msg->iova, msg->size); atomic64_sub(npages, &dev->mm->pinned_vm); } - up_read(&dev->mm->mmap_sem); + mmap_read_unlock(dev->mm); free_page((unsigned long)page_list); return ret; } @@ -694,7 +741,7 @@ static int vhost_vdpa_open(struct inode *inode, struct file *filep) vqs[i] = &v->vqs[i]; vqs[i]->handle_kick = handle_vq_kick; } - vhost_dev_init(dev, vqs, nvqs, 0, 0, 0, + vhost_dev_init(dev, vqs, nvqs, 0, 0, 0, false, vhost_vdpa_process_iotlb_msg); dev->iotlb = vhost_iotlb_alloc(0, 0); @@ -729,6 +776,7 @@ static int vhost_vdpa_release(struct inode *inode, struct file *filep) vhost_dev_stop(&v->vdev); vhost_vdpa_iotlb_free(v); vhost_vdpa_free_domain(v); + vhost_vdpa_config_put(v); vhost_dev_cleanup(&v->vdev); kfree(v->vdev.vqs); mutex_unlock(&d->mutex); @@ -739,12 +787,74 @@ static int vhost_vdpa_release(struct inode *inode, struct file *filep) return 0; } +#ifdef CONFIG_MMU +static vm_fault_t vhost_vdpa_fault(struct vm_fault *vmf) +{ + struct vhost_vdpa *v = vmf->vma->vm_file->private_data; + struct vdpa_device *vdpa = v->vdpa; + const struct vdpa_config_ops *ops = vdpa->config; + struct vdpa_notification_area notify; + struct vm_area_struct *vma = vmf->vma; + u16 index = vma->vm_pgoff; + + notify = ops->get_vq_notification(vdpa, index); + + vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); + if (remap_pfn_range(vma, vmf->address & PAGE_MASK, + notify.addr >> PAGE_SHIFT, PAGE_SIZE, + vma->vm_page_prot)) + return VM_FAULT_SIGBUS; + + return VM_FAULT_NOPAGE; +} + +static const struct vm_operations_struct vhost_vdpa_vm_ops = { + .fault = vhost_vdpa_fault, +}; + +static int vhost_vdpa_mmap(struct file *file, struct vm_area_struct *vma) +{ + struct vhost_vdpa *v = vma->vm_file->private_data; + struct vdpa_device *vdpa = v->vdpa; + const struct vdpa_config_ops *ops = vdpa->config; + struct vdpa_notification_area notify; + int index = vma->vm_pgoff; + + if (vma->vm_end - vma->vm_start != PAGE_SIZE) + return -EINVAL; + if ((vma->vm_flags & VM_SHARED) == 0) + return -EINVAL; + if (vma->vm_flags & VM_READ) + return -EINVAL; + if (index > 65535) + return -EINVAL; + if (!ops->get_vq_notification) + return -ENOTSUPP; + + /* To be safe and easily modelled by userspace, We only + * support the doorbell which sits on the page boundary and + * does not share the page with other registers. + */ + notify = ops->get_vq_notification(vdpa, index); + if (notify.addr & (PAGE_SIZE - 1)) + return -EINVAL; + if (vma->vm_end - vma->vm_start != notify.size) + return -ENOTSUPP; + + vma->vm_ops = &vhost_vdpa_vm_ops; + return 0; +} +#endif /* CONFIG_MMU */ + static const struct file_operations vhost_vdpa_fops = { .owner = THIS_MODULE, .open = vhost_vdpa_open, .release = vhost_vdpa_release, .write_iter = vhost_vdpa_chr_write_iter, .unlocked_ioctl = vhost_vdpa_unlocked_ioctl, +#ifdef CONFIG_MMU + .mmap = vhost_vdpa_mmap, +#endif /* CONFIG_MMU */ .compat_ioctl = compat_ptr_ioctl, }; |