drm/gem-shmem: Compute dumb-buffer sizes with drm_mode_size_dumb()

Call drm_mode_size_dumb() to compute dumb-buffer scanline pitch and
buffer size. Align the pitch to a multiple of 8.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Link: https://lore.kernel.org/r/20250821081918.79786-5-tzimmermann@suse.de

diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_gem_shmem_helper.c
index 50594cf8e17cc7cdad6b1de75d839d4e981a98b5..dc94a27710e5f48839a5d2e9e9ea5152ff22e438 100644 (file)
--- a/drivers/gpu/drm/drm_gem_shmem_helper.c
+++ b/drivers/gpu/drm/drm_gem_shmem_helper.c
@@ -18,6 +18,7 @@
 #include <drm/drm.h>
 #include <drm/drm_device.h>
 #include <drm/drm_drv.h>
+#include <drm/drm_dumb_buffers.h>
 #include <drm/drm_gem_shmem_helper.h>
 #include <drm/drm_prime.h>
 #include <drm/drm_print.h>
@@ -556,18 +557,11 @@ EXPORT_SYMBOL_GPL(drm_gem_shmem_purge_locked);
 int drm_gem_shmem_dumb_create(struct drm_file *file, struct drm_device *dev,
                              struct drm_mode_create_dumb *args)
 {
-       u32 min_pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
+       int ret;
 
-       if (!args->pitch || !args->size) {
-               args->pitch = min_pitch;
-               args->size = PAGE_ALIGN(args->pitch * args->height);
-       } else {
-               /* ensure sane minimum values */
-               if (args->pitch < min_pitch)
-                       args->pitch = min_pitch;
-               if (args->size < args->pitch * args->height)
-                       args->size = PAGE_ALIGN(args->pitch * args->height);
-       }
+       ret = drm_mode_size_dumb(dev, args, SZ_8, 0);
+       if (ret)
+               return ret;
 
        return drm_gem_shmem_create_with_handle(file, dev, args->size, &args->handle);
 }