[llvm] [OFFLOAD] Extend olMemRegister API to handle cases when a memory block may have been mapped outside of liboffload. (PR #172226)

[Kevin Sala Penades via llvm-commits]

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@@ -880,16 +841,17 @@ struct GenericDeviceTy : public DeviceAllocatorTy {
   /// Deallocate data from the device or involving the device.
   Error dataDelete(void *TgtPtr, TargetAllocTy Kind);
 
-  /// Pin host memory to optimize transfers and return the device accessible
-  /// pointer that devices should use for memory transfers involving the host
-  /// pinned allocation.
-  Expected<void *> dataLock(void *HstPtr, int64_t Size) {
-    return PinnedAllocs.lockHostBuffer(HstPtr, Size);
+  /// Pin or register host memory to optimize transfers and return the device
+  /// accessible pointer that devices should use for memory transfers involving
+  /// the host pinned allocation.
+  Expected<void *> registerMemory(void *HstPtr, int64_t Size,
+                                  bool LockMemory = true) {
+    return PinnedAllocs.registerMemory(HstPtr, Size, LockMemory);
   }
 
-  /// Unpin a host memory buffer that was previously pinned.
-  Error dataUnlock(void *HstPtr) {
-    return PinnedAllocs.unlockHostBuffer(HstPtr);
+  /// Unpin or unregister a host memory buffer that was previously pinned.
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kevinsala wrote:

`Unregisters and optionally page-unlocks...`

https://github.com/llvm/llvm-project/pull/172226