From e9679f83091072ca6d3e4ed9c5ce066ba1ed7c65 Mon Sep 17 00:00:00 2001
From: raphaelthegreat <47210458+raphaelthegreat@users.noreply.github.com>
Date: Sat, 8 Jun 2024 19:10:32 +0300
Subject: [PATCH] address_space: Don't reserve space again

---
 src/core/address_space.cpp | 21 ++++++++++++++++++---
 src/core/memory.cpp        |  5 +----
 2 files changed, 19 insertions(+), 7 deletions(-)

diff --git a/src/core/address_space.cpp b/src/core/address_space.cpp
index 409b453b..fe9780f5 100644
--- a/src/core/address_space.cpp
+++ b/src/core/address_space.cpp
@@ -116,6 +116,7 @@ struct AddressSpace::Impl {
     void* MapPrivate(VAddr virtual_addr, size_t size, u64 alignment, ULONG prot,
                      bool no_commit = false) {
         // Map a private allocation
+        PVOID addr = reinterpret_cast<PVOID>(virtual_addr);
         MEM_ADDRESS_REQUIREMENTS req{};
         MEM_EXTENDED_PARAMETER param{};
         // req.LowestStartingAddress =
@@ -129,9 +130,23 @@ struct AddressSpace::Impl {
         if (!no_commit) {
             alloc_type |= MEM_COMMIT;
         }
-        void* const ptr = VirtualAlloc2(process, reinterpret_cast<PVOID>(virtual_addr), size,
-                                        alloc_type, prot, &param, 1);
-        ASSERT_MSG(ptr, "{}", Common::GetLastErrorMsg());
+        // Check if the area has been reserved beforehand (typically for tesselation buffer)
+        // and in that case don't reserve it again as Windows complains.
+        if (virtual_addr) {
+            MEMORY_BASIC_INFORMATION info;
+            VirtualQuery(addr, &info, sizeof(info));
+            if (info.State == MEM_RESERVE) {
+                alloc_type &= ~MEM_RESERVE;
+            }
+        }
+        void* ptr{};
+        if (virtual_addr) {
+            ptr = VirtualAlloc2(process, addr, size, alloc_type, prot, NULL, 0);
+            ASSERT_MSG(ptr && VAddr(ptr) == virtual_addr, "{}", Common::GetLastErrorMsg());
+        } else {
+            ptr = VirtualAlloc2(process, nullptr, size, alloc_type, prot, &param, 1);
+            ASSERT_MSG(ptr, "{}", Common::GetLastErrorMsg());
+        }
         return ptr;
     }
 
diff --git a/src/core/memory.cpp b/src/core/memory.cpp
index acae3b52..5180a633 100644
--- a/src/core/memory.cpp
+++ b/src/core/memory.cpp
@@ -92,10 +92,7 @@ int MemoryManager::MapMemory(void** out_addr, VAddr virtual_addr, size_t size, M
             it++;
         }
         ASSERT(it != vma_map.end());
-        if (alignment > 0) {
-            ASSERT_MSG(it->second.base % alignment == 0, "Free region base is not aligned");
-        }
-        mapped_addr = it->second.base;
+        mapped_addr = alignment > 0 ? Common::AlignUp(it->second.base, alignment) : it->second.base;
     }
 
     // Perform the mapping.