[PATCH v3 2/4] fbdev: Add flag indicating framebuffer is allocated from kernel memory

mhkelley58
2025-05-23T16:15:44Z

From: Michael Kelley <mhklinux@outlook.com>

Add a flag that fbdev drivers can set to indicate that the framebuffer
memory comes from alloc_pages() or similar as opposed to vmalloc()
memory. The flag is to be used by fbdev deferred I/O.

Signed-off-by: Michael Kelley <mhklinux@outlook.com>
---
Changes in v3:
* This patch is new in v3. The definition of FBINFO_KMEMFB
was previously combined into the next patch of the series.
[Helge Deller]

include/linux/fb.h | 1 +
1 file changed, 1 insertion(+)

diff --git a/include/linux/fb.h b/include/linux/fb.h
index 05cc251035da..a1121116eef0 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -396,6 +396,7 @@ struct fb_tile_ops {

/* hints */
#define FBINFO_VIRTFB 0x0004 /* FB is System RAM, not device. */
+#define FBINFO_KMEMFB 0x0008 /* FB is allocated in contig kernel mem */
#define FBINFO_PARTIAL_PAN_OK 0x0040 /* otw use pan only for double-buffering */
#define FBINFO_READS_FAST 0x0080 /* soft-copy faster than rendering */

--
2.25.1