From: Your Name <you@xxxxxxxxxxx> 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@xxxxxxxxxx> --- drivers/vdpa/vdpa_user/vduse_dev.c | 49 ++++++++++++++++++++++++++++++ 1 file changed, 49 insertions(+) diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c index f845dc46b1db..1b833bf0ae37 100644 --- a/drivers/vdpa/vdpa_user/vduse_dev.c +++ b/drivers/vdpa/vdpa_user/vduse_dev.c @@ -1313,6 +1313,54 @@ 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 vdpa_reconnect_info *info; + info = &dev->reconnect_info[index]; + + 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_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; + + 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; + + info = &dev->reconnect_info[index]; + if (info->addr & (PAGE_SIZE - 1)) + return -EINVAL; + if (vma->vm_end - vma->vm_start != info->size) { + return -ENOTSUPP; + } + + vm_flags_set(vma, VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP); + vma->vm_ops = &vduse_vm_ops; + + return 0; +} + static int vduse_dev_open(struct inode *inode, struct file *file) { int ret; @@ -1345,6 +1393,7 @@ static const struct file_operations vduse_dev_fops = { .unlocked_ioctl = vduse_dev_ioctl, .compat_ioctl = compat_ptr_ioctl, .llseek = noop_llseek, + .mmap = vduse_mmap, }; static struct vduse_dev *vduse_dev_create(void) -- 2.34.3