Initial Changes for RDMA as a platform for MsQuic #5113

srsubra · 2025-05-22T17:21:36Z

this PR is mainly for help with debugging issues with datapath tests. A New PR will be raised only the code has completed testing

…quic into srsubra/msquic_rdma

…ra/msquic_rdma

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guhetier

Review in progress, making my way through the RDMA code.
Added a few generic comments.

guhetier · 2025-05-28T18:04:31Z

src/platform/datapath_xplat.c

@@ -37,6 +38,7 @@ CxPlatDataPathInitialize(
            ClientRecvContextLength,
            UdpCallbacks,
            TcpCallbacks,
+            RdmaCallbacks,


We need to clarify which design we follow for RDMA, between the "TCP / UDP" one and the "normal/xdp" one.
Which is tricky, because RDMA is a protocol (like udp/tcp) but it also largely align with what we do for xdp (co-exists as an alternative pipe to the network).

Maybe it will have to be part of a bigger refactoring of the datapath, later.

guhetier · 2025-05-28T18:05:44Z

src/platform/datapath_win.c

@@ -25,7 +25,7 @@ CxPlatSocketUpdateQeo(
    )
 {
    if (Socket->UseTcp || (Socket->RawSocketAvailable &&
-        !IS_LOOPBACK(Offloads[0].Address))) {
+        !IS_LOOPBACK(Offloads[0].Address))) {   


nit: Random witespaces

guhetier · 2025-05-28T18:12:51Z

src/inc/quic_datapath.h

+//
+// The following APIs are specific for RDMA Implementation
+//
+#define CXPLAT_RDMA_FLAG_SHARE_ENDPOINT     0x00000001   // Forces sharing of the address and port


Please use an enum for flags.

guhetier · 2025-05-28T18:23:31Z

src/platform/datapath_winuser.c

@@ -2643,7 +2705,8 @@ CxPlatSocketRelease(
    _In_ CXPLAT_SOCKET* Socket
    )
 {
-    if (CxPlatRefDecrement(&Socket->RefCount)) {
+    if (CxPlatRefDecrement(&Socket->RefCount))
+    {


nit: We try to keep a consistent style. Before we conclude the PR, we will need to fix it ({ are opened on the line of the if, a few spaces issues, etc... through the PR).

I won't comment on it for now, just a todo for later.

guhetier · 2025-05-28T22:33:03Z

src/platform/dbcc.vcxproj

@@ -0,0 +1,138 @@
+<Project ToolsVersion="Current">


File checked in by mistake?

guhetier · 2025-05-29T00:03:38Z