fbdev: Push pgprot_decrypted() into mmap implementations

If a driver sets struct fb_ops.fb_mmap, the fbdev core automatically
calls pgprot_decrypted(). But the default fb_mmap code doesn't handle
pgprot_decrypted().

Move the call to pgprot_decrypted() into each drivers' fb_mmap function.
This only concerns fb_mmap functions for system and DMA memory. For
I/O memory, which is the default case, nothing changes. The fb_mmap
for I/O-memory can later be moved into a helper as well.

DRM's fbdev emulation handles pgprot_decrypted() internally via the
Prime helpers. Fbdev doesn't have to do anything in this case. In
cases where DRM uses deferred I/O, this patch updates fb_mmap correctly.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231127131655.4020-30-tzimmermann@suse.de

drivers/auxdisplay/cfag12864bfb.c

@@ -51,6 +51,8 @@ static int cfag12864bfb_mmap(struct fb_info *info, struct vm_area_struct *vma)
 {
 	struct page *pages = virt_to_page(cfag12864b_buffer);
 
+	vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
+
 	return vm_map_pages_zero(vma, &pages, 1);
 }
 

drivers/auxdisplay/ht16k33.c

@@ -351,6 +351,8 @@ static int ht16k33_mmap(struct fb_info *info, struct vm_area_struct *vma)
 	struct ht16k33_priv *priv = info->par;
 	struct page *pages = virt_to_page(priv->fbdev.buffer);
 
+	vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
+
 	return vm_map_pages_zero(vma, &pages, 1);
 }
 

drivers/video/fbdev/amba-clcd.c

@@ -829,6 +829,8 @@ static int clcdfb_of_dma_setup(struct clcd_fb *fb)
 
 static int clcdfb_of_dma_mmap(struct clcd_fb *fb, struct vm_area_struct *vma)
 {
+	vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
+
 	return dma_mmap_wc(&fb->dev->dev, vma, fb->fb.screen_base,
 			   fb->fb.fix.smem_start, fb->fb.fix.smem_len);
 }

drivers/video/fbdev/au1100fb.c

@@ -342,6 +342,8 @@ int au1100fb_fb_mmap(struct fb_info *fbi, struct vm_area_struct *vma)
 {
 	struct au1100fb_device *fbdev = to_au1100fb_device(fbi);
 
+	vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
+
 	pgprot_val(vma->vm_page_prot) |= (6 << 9); //CCA=6
 
 	return dma_mmap_coherent(fbdev->dev, vma, fbdev->fb_mem, fbdev->fb_phys,

drivers/video/fbdev/au1200fb.c

@@ -1236,6 +1236,8 @@ static int au1200fb_fb_mmap(struct fb_info *info, struct vm_area_struct *vma)
 {
 	struct au1200fb_device *fbdev = info->par;
 
+	vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
+
 	return dma_mmap_coherent(fbdev->dev, vma,
 				 fbdev->fb_mem, fbdev->fb_phys, fbdev->fb_len);
 }

drivers/video/fbdev/core/fb_chrdev.c

@@ -325,11 +325,6 @@ static int fb_mmap(struct file *file, struct vm_area_struct *vma)
 	if (info->fbops->fb_mmap) {
 		int res;
 
-		/*
-		 * The framebuffer needs to be accessed decrypted, be sure
-		 * SME protection is removed ahead of the call
-		 */
-		vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
 		res = info->fbops->fb_mmap(info, vma);
 		mutex_unlock(&info->mm_lock);
 		return res;

drivers/video/fbdev/core/fb_defio.c

@@ -227,6 +227,8 @@ static const struct address_space_operations fb_deferred_io_aops = {
 
 int fb_deferred_io_mmap(struct fb_info *info, struct vm_area_struct *vma)
 {
+	vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
+
 	vma->vm_ops = &fb_deferred_io_vm_ops;
 	vm_flags_set(vma, VM_DONTEXPAND | VM_DONTDUMP);
 	if (!(info->flags & FBINFO_VIRTFB))

drivers/video/fbdev/ep93xx-fb.c

@@ -311,6 +311,8 @@ static int ep93xxfb_mmap(struct fb_info *info, struct vm_area_struct *vma)
 {
 	unsigned int offset = vma->vm_pgoff << PAGE_SHIFT;
 
+	vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
+
 	if (offset < info->fix.smem_len) {
 		return dma_mmap_wc(info->device, vma, info->screen_base,
 				   info->fix.smem_start, info->fix.smem_len);

drivers/video/fbdev/gbefb.c

@@ -1000,6 +1000,8 @@ static int gbefb_mmap(struct fb_info *info,
 	unsigned long phys_addr, phys_size;
 	u16 *tile;
 
+	vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
+
 	/* check range */
 	if (vma->vm_pgoff > (~0UL >> PAGE_SHIFT))
 		return -EINVAL;

drivers/video/fbdev/omap/omapfb_main.c

@@ -1203,6 +1203,8 @@ static int omapfb_mmap(struct fb_info *info, struct vm_area_struct *vma)
 	struct omapfb_device *fbdev = plane->fbdev;
 	int r;
 
+	vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
+
 	omapfb_rqueue_lock(fbdev);
 	r = fbdev->ctrl->mmap(info, vma);
 	omapfb_rqueue_unlock(fbdev);

drivers/video/fbdev/omap2/omapfb/omapfb-main.c

@@ -1095,6 +1095,8 @@ static int omapfb_mmap(struct fb_info *fbi, struct vm_area_struct *vma)
 	u32 len;
 	int r;
 
+	vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
+
 	rg = omapfb_get_mem_region(ofbi->region);
 
 	start = omapfb_get_region_paddr(ofbi);

drivers/video/fbdev/ps3fb.c

@@ -708,6 +708,8 @@ static int ps3fb_mmap(struct fb_info *info, struct vm_area_struct *vma)
 {
 	int r;
 
+	vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
+
 	r = vm_iomap_memory(vma, info->fix.smem_start, info->fix.smem_len);
 
 	dev_dbg(info->device, "ps3fb: mmap framebuffer P(%lx)->V(%lx)\n",

drivers/video/fbdev/sa1100fb.c

@@ -562,6 +562,8 @@ static int sa1100fb_mmap(struct fb_info *info,
 		container_of(info, struct sa1100fb_info, fb);
 	unsigned long off = vma->vm_pgoff << PAGE_SHIFT;
 
+	vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
+
 	if (off < info->fix.smem_len) {
 		vma->vm_pgoff += 1; /* skip over the palette */
 		return dma_mmap_wc(fbi->dev, vma, fbi->map_cpu, fbi->map_dma,

drivers/video/fbdev/sbuslib.c

@@ -60,6 +60,7 @@ int sbusfb_mmap_helper(struct sbus_mmap_map *map,
 
 	/* VM_IO | VM_DONTEXPAND | VM_DONTDUMP are set by remap_pfn_range() */
 
+	vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
 	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 
 	/* Each page, see which map applies */

drivers/video/fbdev/sh_mobile_lcdcfb.c

@@ -1482,6 +1482,8 @@ sh_mobile_lcdc_overlay_mmap(struct fb_info *info, struct vm_area_struct *vma)
 	if (info->fbdefio)
 		return fb_deferred_io_mmap(info, vma);
 
+	vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
+
 	return dma_mmap_coherent(ovl->channel->lcdc->dev, vma, ovl->fb_mem,
 				 ovl->dma_handle, ovl->fb_size);
 }
@@ -1956,6 +1958,8 @@ sh_mobile_lcdc_mmap(struct fb_info *info, struct vm_area_struct *vma)
 	if (info->fbdefio)
 		return fb_deferred_io_mmap(info, vma);
 
+	vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
+
 	return dma_mmap_coherent(ch->lcdc->dev, vma, ch->fb_mem,
 				 ch->dma_handle, ch->fb_size);
 }

drivers/video/fbdev/smscufx.c

@@ -783,6 +783,8 @@ static int ufx_ops_mmap(struct fb_info *info, struct vm_area_struct *vma)
 	if (info->fbdefio)
 		return fb_deferred_io_mmap(info, vma);
 
+	vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
+
 	if (vma->vm_pgoff > (~0UL >> PAGE_SHIFT))
 		return -EINVAL;
 	if (size > info->fix.smem_len)

drivers/video/fbdev/udlfb.c

@@ -331,6 +331,8 @@ static int dlfb_ops_mmap(struct fb_info *info, struct vm_area_struct *vma)
 	if (info->fbdefio)
 		return fb_deferred_io_mmap(info, vma);
 
+	vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
+
 	if (vma->vm_pgoff > (~0UL >> PAGE_SHIFT))
 		return -EINVAL;
 	if (size > info->fix.smem_len)

drivers/video/fbdev/vermilion/vermilion.c

@@ -998,6 +998,8 @@ static int vmlfb_mmap(struct fb_info *info, struct vm_area_struct *vma)
 	int ret;
 	unsigned long prot;
 
+	vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
+
 	ret = vmlfb_vram_offset(vinfo, offset);
 	if (ret)
 		return -EINVAL;

drivers/video/fbdev/vfb.c

@@ -382,6 +382,8 @@ static int vfb_pan_display(struct fb_var_screeninfo *var,
 static int vfb_mmap(struct fb_info *info,
 		    struct vm_area_struct *vma)
 {
+	vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
+
 	return remap_vmalloc_range(vma, (void *)info->fix.smem_start, vma->vm_pgoff);
 }