Hi Thomas,
> diff --git a/drivers/video/fbdev/core/fb_defio.c
> b/drivers/video/fbdev/core/fb_defio.c
> index 6aaf6d0abf39..6924d489a289 100644
> --- a/drivers/video/fbdev/core/fb_defio.c
> +++ b/drivers/video/fbdev/core/fb_defio.c
> @@ -181,6 +181,7 @@ int fb_deferred_io_mmap(struct fb_info *info, struct
> vm_area_struct *vma)
> vma->vm_private_data = info;
> return 0;
> }
> +EXPORT_SYMBOL_GPL(fb_deferred_io_mmap);
>
> /* workqueue callback */
> static void fb_deferred_io_work(struct work_struct *work)
> diff --git a/drivers/video/fbdev/core/fbmem.c
> b/drivers/video/fbdev/core/fbmem.c
> index 84427470367b..52440e3f8f69 100644
> --- a/drivers/video/fbdev/core/fbmem.c
> +++ b/drivers/video/fbdev/core/fbmem.c
> @@ -1334,7 +1334,6 @@ static int
> fb_mmap(struct file *file, struct vm_area_struct * vma)
> {
> struct fb_info *info = file_fb_info(file);
> - int (*fb_mmap_fn)(struct fb_info *info, struct vm_area_struct *vma);
> unsigned long mmio_pgoff;
> unsigned long start;
> u32 len;
> @@ -1343,14 +1342,7 @@ fb_mmap(struct file *file, struct vm_area_struct * vma)
> return -ENODEV;
> mutex_lock(&info->mm_lock);
>
> - fb_mmap_fn = info->fbops->fb_mmap;
> -
> -#if IS_ENABLED(CONFIG_FB_DEFERRED_IO)
> - if (info->fbdefio)
> - fb_mmap_fn = fb_deferred_io_mmap;
> -#endif
> -
> - if (fb_mmap_fn) {
> + if (info->fbops->fb_mmap) {
> int res;
>
> /*
> @@ -1358,11 +1350,18 @@ fb_mmap(struct file *file, struct vm_area_struct *
> vma)
> * SME protection is removed ahead of the call
> */
> vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
> - res = fb_mmap_fn(info, vma);
> + res = info->fbops->fb_mmap(info, vma);
> mutex_unlock(&info->mm_lock);
> return res;
> }
>
> + /*
> + * FB deferred I/O wants you to handle mmap in your drivers. At a
> + * minimum, point struct fb_ops.fb_mmap to fb_deferred_io_mmap().
> + */
> + if (dev_WARN_ONCE(info->dev, info->fbdefio, "fbdev mmap not set up for
> defered I/O.\n"))
> + return -ENODEV;
> +
If not configured - then why not just call fb_deferred_io_mmap(), as
this seems to be the default implementation anyway.
Then drivers that needs it can override - and the rest fallback to the
default.
Sam
