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