Re: graphics/drm-61-kmod build failure for main-n276560-83dcc133c876

On Sat, Apr 19, 2025 at 06:06:59AM -0700, David Wolfskill wrote:
> Running:
> FreeBSD g1-118.catwhisker.org 15.0-CURRENT FreeBSD 15.0-CURRENT #445 main-n276537-7121e9414f29: Fri Apr 18 12:36:30 UTC 2025     root@g1-120.catwhisker.org:/common/S4/obj/usr/src/amd64.amd64/sys/CANARY amd64
> 
> after updating sources to main-n276560-83dcc133c876, with a ports tree
> at main-n703265-33b43edfb65d, I find:
> 
> ...
> --- i915_gem_mman.o ---
> /common/S4/obj/usr/src/amd64.amd64/sys/CANARY/common/ports/graphics/drm-61-kmod/work/drm-kmod-drm_v6.1.128_1/drivers/gpu/drm/i915/gem/i915_gem_mman.c:171:77: error: call to undeclared function 'vm_page_next'; ISO C99 and later do not support implicit function declarations [-Werror,-Wimplicit-function-declaration]
>   171 |                         for (vm_page_t page = vm_page_find_least(vmobj, 0); page != NULL; page = vm_page_next(page)) {
>       |                                                                                                  ^
> /common/S4/obj/usr/src/amd64.amd64/sys/CANARY/common/ports/graphics/drm-61-kmod/work/drm-kmod-drm_v6.1.128_1/drivers/gpu/drm/i915/gem/i915_gem_mman.c:171:75: error: incompatible integer to pointer conversion assigning to 'vm_page_t' (aka 'struct vm_page *') from 'int' [-Wint-conversion]
>   171 |                         for (vm_page_t page = vm_page_find_least(vmobj, 0); page != NULL; page = vm_page_next(page)) {
>       |                                                                                                ^ ~~~~~~~~~~~~~~~~~~
> 2 errors generated.
> *** [i915_gem_mman.o] Error code 1
> 
> make[1]: stopped making "all" in /common/S4/obj/usr/src/amd64.amd64/sys/CANARY/common/ports/graphics/drm-61-kmod/work/drm-kmod-drm_v6.1.128_1/i915
> make[1]: 1 error
> [end of excerpt from typescript -- dhw]
> 
> This is using METAMODE (as I've done for ages, now); unfortunately:
> 
> .ERROR_TARGET='all'
> .ERROR_META_FILE=''
> .MAKE.LEVEL='2'
> MAKEFILE=''
> 
> so not much to be gained there (that I can see).

Something like the following diff is needed.  It needs to be built
against the latest main, where __FreeBSD_version is bumped.

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
index 2a9946c7d0..f61eeefe7a 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
@@ -34,6 +34,7 @@
 #include <vm/vm_object.h>
 #include <vm/vm_pager.h>
 #include <vm/vm_param.h>
+#include <vm/vm_radix.h>
 #endif
 
 #ifdef __linux__ /* Mute unused function warning. */
@@ -168,9 +169,16 @@ i915_gem_mmap_ioctl(struct drm_device *dev, void *data,
 	if ((rv == KERN_SUCCESS) && (args->flags & I915_MMAP_WC)) {
 		VM_OBJECT_WLOCK(vmobj);
 		if (vm_object_set_memattr(vmobj, VM_MEMATTR_WRITE_COMBINING) != KERN_SUCCESS) {
-			for (vm_page_t page = vm_page_find_least(vmobj, 0); page != NULL; page = vm_page_next(page)) {
+#if __FreeBSD_version >= 1500038
+			struct pctrie_iter pages;
+			vm_page_t page;
+
+			vm_page_iter_init(&pages, vmobj);
+			VM_RADIX_FORALL(page, &pages)
+#else
+			for (vm_page_t page = vm_page_find_least(vmobj, 0); page != NULL; page = vm_page_next(page))
+#endif
 				pmap_page_set_memattr(page, VM_MEMATTR_WRITE_COMBINING);
-			}
 		}
 		VM_OBJECT_WUNLOCK(vmobj);
 	}