graphics: upload streamed texture mips from sparse reservations

src/graphics/host_gpu/renderer/cache/bufferCache.cpp

@@ -491,8 +491,7 @@ std::pair<Buffer*, uint64_t> BufferCache::ObtainBufferForImage(uint64_t vaddr, u
 	}
 
 	auto [staging, stage_offset] = m_staging_buffer.Map(size, 16);
-	if (staging == nullptr || (!Libs::LibKernel::Memory::TryReadBacking(vaddr, staging, size) &&
-	                           !Libs::LibKernel::Memory::TryReadPrtBacking(vaddr, staging, size))) {
+	if (staging == nullptr || !Libs::LibKernel::Memory::TryReadSparseBacking(vaddr, staging, size)) {
 		EXIT("BufferCache: failed to read mapped guest image backing\n");
 	}
 	m_staging_buffer.Commit();

src/kernel/memory.cpp

@@ -963,10 +963,9 @@ static bool IsInPrtAperture(uint64_t address, uint64_t size = 1) {
 	return false;
 }
 
-bool TryReadPrtBacking(uint64_t vaddr, void* data, uint64_t size) {
+bool TryReadSparseBacking(uint64_t vaddr, void* data, uint64_t size) {
 	std::vector<VirtualRanges::Range> ranges;
-	if (g_guest_address_space == nullptr || g_virtual_ranges == nullptr ||
-	    !IsInPrtAperture(vaddr, size) || !g_virtual_ranges->QuerySpan(vaddr, size, &ranges)) {
+	if (!g_virtual_ranges->QuerySpan(vaddr, size, &ranges)) {
 		return false;
 	}
 	if (std::any_of(ranges.begin(), ranges.end(), [](const auto& range) {

src/kernel/memory.h

@@ -115,7 +115,7 @@ int MapAutomaticMemory(uint64_t vaddr, size_t size, int type, int prot);
 bool                   TryWriteBacking(uint64_t vaddr, const void* data, uint64_t size);
 bool                   TryReadBacking(uint64_t vaddr, void* data, uint64_t size);
 bool                   TryReadGpuCleanBacking(uint64_t vaddr, void* data, uint64_t size);
-bool                   TryReadPrtBacking(uint64_t vaddr, void* data, uint64_t size);
+bool                   TryReadSparseBacking(uint64_t vaddr, void* data, uint64_t size);
 [[nodiscard]] uint64_t ClampRangeSize(uint64_t vaddr, uint64_t size);
 void                   WriteBacking(uint64_t vaddr, const void* data, uint64_t size) noexcept;
 void                   InvalidateMemory(uint64_t vaddr, uint64_t size);

src/kernel/memoryAddressSpace.inc

@@ -212,14 +212,21 @@ public:
 		}
 
 		auto* destination = static_cast<uint8_t*>(data);
-		std::memset(destination, 0, size);
+		auto  cursor      = vaddr;
 		for (auto mapping = first; mapping != m_maps.end() && mapping->second.vaddr < end;
 		     ++mapping) {
 			const auto& entry  = mapping->second;
 			const auto  start  = std::max(vaddr, entry.vaddr);
 			const auto  bytes  = std::min(end, entry.vaddr + entry.size) - start;
 			const auto  offset = entry.backing_offset + start - entry.vaddr;
+			if (cursor < start) {
+				std::memset(destination + cursor - vaddr, 0, start - cursor);
+			}
 			std::memcpy(destination + start - vaddr, m_backing_base + offset, bytes);
+			cursor = start + bytes;
+		}
+		if (cursor < end) {
+			std::memset(destination + cursor - vaddr, 0, end - cursor);
 		}
 		return true;
 	}