nouveau/vmm: increase size of vmm pte tracker struct to u32 (v2)

We need to tracker large counts of spte than previously due to unref
getting delayed sometimes.

This doesn't fix LPT tracking yet, it just creates space for it.

Reviewed-by: Mary Guillemard <mary@mary.zone>
Tested-by: Mary Guillemard <mary@mary.zone>
Tested-by: Mel Henning <mhenning@darkrefraction.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Link: https://patch.msgid.link/20260204030208.2313241-3-airlied@gmail.com

Author: airlied

drivers/gpu/drm/nouveau/nvkm/subdev/mmu/vmm.c

@@ -387,7 +387,7 @@ nvkm_vmm_sparse_ptes(const struct nvkm_vmm_desc *desc,
 	} else
 	if (desc->type == LPT) {
 		union nvkm_pte_tracker sparse = { .s.sparse = 1 };
-		memset(&pgt->pte[ptei].u, sparse.u, ptes);
+		memset32(&pgt->pte[ptei].u, sparse.u, ptes);
 	}
 }
 
@@ -399,7 +399,7 @@ nvkm_vmm_sparse_unref_ptes(struct nvkm_vmm_iter *it, bool pfn, u32 ptei, u32 pte
 		memset(&pt->pde[ptei], 0x00, sizeof(pt->pde[0]) * ptes);
 	else
 	if (it->desc->type == LPT)
-		memset(&pt->pte[ptei].u, 0x00, sizeof(pt->pte[0]) * ptes);
+		memset32(&pt->pte[ptei].u, 0x00, ptes);
 	return nvkm_vmm_unref_ptes(it, pfn, ptei, ptes);
 }
 
@@ -458,7 +458,7 @@ nvkm_vmm_ref_hwpt(struct nvkm_vmm_iter *it, struct nvkm_vmm_pt *pgd, u32 pdei)
 					desc->func->sparse(vmm, pt, pteb, ptes);
 				else
 					desc->func->invalid(vmm, pt, pteb, ptes);
-				memset(&pgt->pte[pteb], 0x00, ptes);
+				memset32(&pgt->pte[pteb].u, 0x00, ptes);
 			} else {
 				desc->func->unmap(vmm, pt, pteb, ptes);
 				while (ptes--)

drivers/gpu/drm/nouveau/nvkm/subdev/mmu/vmm.h

@@ -5,11 +5,12 @@
 enum nvkm_memory_target;
 
 union nvkm_pte_tracker {
-	u8 u;
+	u32 u;
 	struct {
-		u8 sparse:1;
-		u8 spte_valid:1;
-		u8 sptes:6;
+		u32 sparse:1;
+		u32 spte_valid:1;
+		u32 padding:14;
+		u32 sptes:16;
 	} s;
 };