rocr: Improve memory protection and WSL compatibility (#2274)

* rocr: Add ProtectMemory API and use it in RemoveAccess
Replace munmap + mmap with mprotect when removing memory access.
This improves performance by 5-10x, ensures atomicity (no race
condition window), and prepares for WSL/DXG compatibility fixes.

Suggested-by: David Yat Sin <David.YatSin@amd.com>
Signed-off-by: Flora Cui <flora.cui@amd.com>
Signed-off-by: Horatio Zhang <Hongkun.Zhang@amd.com>

* rocr: Skip CPU mapping operations on WSL
On WSL, CPU cannot access GPU VRAM due to platform restrictions.
CPU access would fault-in system RAM instead, causing data corruption
and memory leaks. Return HSA_STATUS_ERROR to fail fast rather than
silently creating broken mappings. GPU-to-GPU mappings remain functional.

Signed-off-by: Flora Cui <flora.cui@amd.com>
Signed-off-by: Horatio Zhang <Hongkun.Zhang@amd.com>

* rocr: reduce ifdef linux
v2: Fix IsDXG check logic

Signed-off-by: David Yat Sin <David.YatSin@amd.com>
Signed-off-by: Horatio Zhang <Hongkun.Zhang@amd.com>

---------
Signed-off-by: Horatio Zhang <Hongkun.Zhang@amd.com>
Signed-off-by: David Yat Sin <David.YatSin@amd.com>
Signed-off-by: Flora Cui <flora.cui@amd.com>

projects/rocr-runtime/runtime/hsa-runtime/core/util/lnx/os_linux.cpp

@@ -930,6 +930,10 @@ bool UncommitMemory(void* addr, size_t size) {
                 0) != MAP_FAILED;
 }
 
+bool ProtectMemory(void* va, size_t size, MemProt perms) {
+  return ::mprotect(va, size, MemProtToOsProt(perms)) == 0;
+}
+
 uint64_t HostTotalPhysicalMemory() {
   static uint64_t totalPhys = 0;
 

projects/rocr-runtime/runtime/hsa-runtime/core/util/os.h

@@ -355,6 +355,8 @@ bool UncommitMemory(void* addr, size_t size);
 bool UnmapMemory(void* addr, size_t size);
 bool MapMemory(void* addr, size_t size, MemProt prot, int fd, uint64_t cpu_addr);
 
+bool ProtectMemory(void* va, size_t size, MemProt perms);
+
 uint64_t HostTotalPhysicalMemory();
 
 /// Find First Set for any OS

projects/rocr-runtime/runtime/hsa-runtime/core/util/win/os_win.cpp

@@ -470,6 +470,14 @@ bool MapMemory(void* addr, size_t size, MemProt perms, int fd [[maybe_unused]],
   return VirtualProtect(addr, size, memProtToOsProt(perms), &OldProtect) != 0;
 }
 
+bool ProtectMemory(void* va, size_t size, MemProt perms) {
+  if (perms == MEM_PROT_NONE) {
+    return UncommitMemory(addr, size);
+  }
+  DWORD oldProt;
+  return VirtualProtect(va, size, memProtToOsProt(perms), &oldProt) != 0;
+}
+
 int Ffs(int i) {
   int res = 0;
   unsigned long index;