| Message ID | 20230912030008.3599514-3-lulu@redhat.com (mailing list archive) |
|---|---|
| State | RFC |
| Headers | show |
| Series | Support reconnection in vduse | expand |
| Context | Check | Description |
|---|---|---|
| netdev/tree_selection | success | Not a local patch |
On Tue, Sep 12, 2023 at 11:00 AM Cindy Lu <lulu@redhat.com> wrote: > > Add the operation for mmap, The user space APP will > use this function to map the pages to userspace > > Signed-off-by: Cindy Lu <lulu@redhat.com> > --- > drivers/vdpa/vdpa_user/vduse_dev.c | 63 ++++++++++++++++++++++++++++++ > 1 file changed, 63 insertions(+) > > diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c > index 4c256fa31fc4..2c69f4004a6e 100644 > --- a/drivers/vdpa/vdpa_user/vduse_dev.c > +++ b/drivers/vdpa/vdpa_user/vduse_dev.c > @@ -1388,6 +1388,67 @@ static struct vduse_dev *vduse_dev_get_from_minor(int minor) > return dev; > } > > +static vm_fault_t vduse_vm_fault(struct vm_fault *vmf) > +{ > + struct vduse_dev *dev = vmf->vma->vm_file->private_data; > + struct vm_area_struct *vma = vmf->vma; > + u16 index = vma->vm_pgoff; > + struct vduse_virtqueue *vq; > + struct vdpa_reconnect_info *info; > + > + if (index == 0) { > + info = &dev->reconnect_status; > + } else { > + vq = &dev->vqs[index - 1]; > + info = &vq->reconnect_info; > + } > + vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); > + if (remap_pfn_range(vma, vmf->address & PAGE_MASK, PFN_DOWN(info->addr), > + PAGE_SIZE, vma->vm_page_prot)) > + return VM_FAULT_SIGBUS; > + return VM_FAULT_NOPAGE; > +} > + > +static const struct vm_operations_struct vduse_vm_ops = { > + .fault = vduse_vm_fault, > +}; > + > +static int vduse_dev_mmap(struct file *file, struct vm_area_struct *vma) > +{ > + struct vduse_dev *dev = file->private_data; > + struct vdpa_reconnect_info *info; > + unsigned long index = vma->vm_pgoff; > + struct vduse_virtqueue *vq; > + > + if (vma->vm_end - vma->vm_start != PAGE_SIZE) > + return -EINVAL; > + if ((vma->vm_flags & VM_SHARED) == 0) > + return -EINVAL; > + > + if (index > 65535) > + return -EINVAL; > + > + if (index == 0) { > + info = &dev->reconnect_status; > + } else { > + vq = &dev->vqs[index - 1]; > + info = &vq->reconnect_info; > + } > + > + if (info->index != index) > + return -EINVAL; Under which case could we meet this? > + > + if (info->addr & (PAGE_SIZE - 1)) > + return -EINVAL; And this? > + if (vma->vm_end - vma->vm_start != info->size) > + return -EOPNOTSUPP; > + > + vm_flags_set(vma, VM_IO | VM_PFNMAP | VM_DONTDUMP); Why do you use VM_IO, VM_PFNMAP and VM_DONTDUMP? Thanks > + vma->vm_ops = &vduse_vm_ops; > + > + return 0; > +} > + > static int vduse_dev_open(struct inode *inode, struct file *file) > { > int ret; > @@ -1420,6 +1481,8 @@ static const struct file_operations vduse_dev_fops = { > .unlocked_ioctl = vduse_dev_ioctl, > .compat_ioctl = compat_ptr_ioctl, > .llseek = noop_llseek, > + .mmap = vduse_dev_mmap, > + > }; > > static struct vduse_dev *vduse_dev_create(void) > -- > 2.34.3 >
diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c index 4c256fa31fc4..2c69f4004a6e 100644 --- a/drivers/vdpa/vdpa_user/vduse_dev.c +++ b/drivers/vdpa/vdpa_user/vduse_dev.c @@ -1388,6 +1388,67 @@ static struct vduse_dev *vduse_dev_get_from_minor(int minor) return dev; } +static vm_fault_t vduse_vm_fault(struct vm_fault *vmf) +{ + struct vduse_dev *dev = vmf->vma->vm_file->private_data; + struct vm_area_struct *vma = vmf->vma; + u16 index = vma->vm_pgoff; + struct vduse_virtqueue *vq; + struct vdpa_reconnect_info *info; + + if (index == 0) { + info = &dev->reconnect_status; + } else { + vq = &dev->vqs[index - 1]; + info = &vq->reconnect_info; + } + vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); + if (remap_pfn_range(vma, vmf->address & PAGE_MASK, PFN_DOWN(info->addr), + PAGE_SIZE, vma->vm_page_prot)) + return VM_FAULT_SIGBUS; + return VM_FAULT_NOPAGE; +} + +static const struct vm_operations_struct vduse_vm_ops = { + .fault = vduse_vm_fault, +}; + +static int vduse_dev_mmap(struct file *file, struct vm_area_struct *vma) +{ + struct vduse_dev *dev = file->private_data; + struct vdpa_reconnect_info *info; + unsigned long index = vma->vm_pgoff; + struct vduse_virtqueue *vq; + + if (vma->vm_end - vma->vm_start != PAGE_SIZE) + return -EINVAL; + if ((vma->vm_flags & VM_SHARED) == 0) + return -EINVAL; + + if (index > 65535) + return -EINVAL; + + if (index == 0) { + info = &dev->reconnect_status; + } else { + vq = &dev->vqs[index - 1]; + info = &vq->reconnect_info; + } + + if (info->index != index) + return -EINVAL; + + if (info->addr & (PAGE_SIZE - 1)) + return -EINVAL; + if (vma->vm_end - vma->vm_start != info->size) + return -EOPNOTSUPP; + + vm_flags_set(vma, VM_IO | VM_PFNMAP | VM_DONTDUMP); + vma->vm_ops = &vduse_vm_ops; + + return 0; +} + static int vduse_dev_open(struct inode *inode, struct file *file) { int ret; @@ -1420,6 +1481,8 @@ static const struct file_operations vduse_dev_fops = { .unlocked_ioctl = vduse_dev_ioctl, .compat_ioctl = compat_ptr_ioctl, .llseek = noop_llseek, + .mmap = vduse_dev_mmap, + }; static struct vduse_dev *vduse_dev_create(void)
Add the operation for mmap, The user space APP will use this function to map the pages to userspace Signed-off-by: Cindy Lu <lulu@redhat.com> --- drivers/vdpa/vdpa_user/vduse_dev.c | 63 ++++++++++++++++++++++++++++++ 1 file changed, 63 insertions(+)