<div dir="ltr">Reviewed-by: Jason Ekstrand <<a href="mailto:jason@jlekstrand.net">jason@jlekstrand.net</a>> <div><div class="gmail_extra"> <div class="gmail_quote">On Tue, Apr 4, 2017 at 5:09 PM, Kenneth Graunke <<a href="mailto:kenneth@whitecape.org" target="_blank">kenneth@whitecape.org</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">On modern systems with 4GB apertures, the size in bytes is 4294967296, or (1ull << 32). The kernel gives us the aperture size as a __u64, which works out great. Unfortunately, libdrm "helpfully" returns the data as a size_t, which on 32-bit systems means it truncates the aperture size to 0 bytes. We've happily reported this value as 0 MB of video memory via GLX_MESA_query_renderer since it was originally exposed. This patch bypasses libdrm and calls the ioctl ourselves so we can use a proper uint64_t, avoiding the 32-bit integer overflow. We now report a proper video memory size on 32-bit systems. --- src/mesa/drivers/dri/i965/intel_screen.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) diff --git a/src/mesa/drivers/dri/i965/intel_screen.c b/src/mesa/drivers/dri/i965/intel_screen.c index 811a9c5a867..f94e8a77c10 100644 --- a/src/mesa/drivers/dri/i965/intel_screen.c +++ b/src/mesa/drivers/dri/i965/intel_screen.c @@ -950,6 +950,17 @@ static const __DRIimageExtension intelImageExtension = { .createImageWithModifiers = intel_create_image_with_modifiers, }; +static uint64_t +get_aperture_size(int fd) +{ + struct drm_i915_gem_get_aperture aperture; + + if (drmIoctl(fd, DRM_IOCTL_I915_GEM_GET_APERTURE, &aperture) != 0) + return 0; + + return aperture.aper_size; +} + static int brw_query_renderer_integer(__DRIscreen *dri_screen, int param, unsigned int *value) @@ -972,10 +983,7 @@ brw_query_renderer_integer(__DRIscreen *dri_screen, * assume that there's some fragmentation, and we start doing extra * flushing, etc. That's the big cliff apps will care about. */ - size_t aper_size; - size_t mappable_size; - - drm_intel_get_aperture_sizes(dri_screen->fd, &mappable_size, &aper_size); + uint64_t aper_size = get_aperture_size(dri_screen->fd); const unsigned gpu_mappable_megabytes = (aper_size / (1024 * 1024)) * 3 / 4; -- 2.12.1 _______________________________________________ mesa-dev mailing list <a href="mailto:mesa-dev@lists.freedesktop.org">mesa-dev@lists.freedesktop.org</a> <a href="https://lists.freedesktop.org/mailman/listinfo/mesa-dev" rel="noreferrer" target="_blank">https://lists.freedesktop.org/mailman/listinfo/mesa-dev</a> </blockquote></div> </div></div></div>