Fix rdma-core 18 build (zrlio#50)

The rdma-core 18 build depends on many more kernel headers than
rdma-core 17. Fix the CCAN includes from the rdma-core 18 headers
because the directory structure in rdma-core was modified, whereas we
keep a more vanilla layout.

Add all of the userspace ABI kernel headers to the source tree so we can
build against the newer rdma-core version.

The updated build has been tested on my local system against rdma-core
17 and 18 and appears to work correctly.

Signed-off-by: Patrick MacArthur <[email protected]>

.gitignore

@@ -4,6 +4,7 @@ config.h*
 config.log
 config.status
 configure
+include/kernel-abi
 libtool
 Makefile
 /Makefile.in

README

@@ -15,6 +15,7 @@ Requirements
  - json-c
  - uthash (included in Fedora, Ubuntu, openSUSE, and EPEL for RHEL
    repositories)
+ - Python 2.7 (for build system)
 
 Setup instructions
 ------------------

config/make_abi_structs.py

@@ -0,0 +1,57 @@
+#!/usr/bin/env python
+# Copied from rdma-core 18.2
+"""This script transforms the structs inside the kernel ABI headers into a define
+of an anonymous struct.
+
+eg
+  struct abc {int foo;};
+becomes
+  #define _STRUCT_abc struct {int foo;};
+
+This allows the exact same struct to be included in the provider wrapper struct:
+
+struct abc_resp {
+   struct ibv_abc ibv_resp;
+   _STRUCT_abc;
+};
+
+Which duplicates the struct layout and naming we have historically used, but
+sources the data directly from the kernel headers instead of manually copying."""
+import re;
+import functools;
+import sys;
+
+def in_struct(ln,FO,nesting=0):
+    """Copy a top level structure over to the #define output, keeping track of
+    nested structures."""
+    if nesting == 0:
+        if re.match(r"(}.*);",ln):
+            FO.write(ln[:-1] + "\n\n");
+            return find_struct;
+
+    FO.write(ln + " \\\n");
+
+    if ln == "struct {" or ln == "union {":
+        return functools.partial(in_struct,nesting=nesting+1);
+
+    if re.match(r"}.*;",ln):
+        return functools.partial(in_struct,nesting=nesting-1);
+    return functools.partial(in_struct,nesting=nesting);
+
+def find_struct(ln,FO):
+    """Look for the start of a top level structure"""
+    if ln.startswith("struct ") or ln.startswith("union "):
+        g = re.match(r"(struct|union)\s+(\S+)\s+{",ln);
+        FO.write("#define _STRUCT_%s %s { \\\n"%(g.group(2),g.group(1)));
+        return in_struct;
+    return find_struct;
+
+with open(sys.argv[1]) as FI:
+    with open(sys.argv[2],"w") as FO:
+        state = find_struct;
+        for ln in FI:
+            # Drop obvious comments
+            ln = ln.strip();
+            ln = re.sub(r"/\*.*\*/","",ln);
+            ln = re.sub(r"//.*$","",ln);
+            state = state(ln,FO);

config/rdma_core.m4

@@ -44,13 +44,13 @@ AC_DEFUN([_URDMA_FUNC_VERBS_INIT_AND_ALLOC_CONTEXT],
 AC_CACHE_CHECK([number of arguments verbs_init_and_alloc_context takes],
 	[dpdk_cv_func_verbs_init_and_alloc_context],
 	[old_CPPFLAGS="${CPPFLAGS}"
-	CPPFLAGS="-I${srcdir} -I${srcdir}/rdma-core/${ibverbs_pabi_version} ${CPPFLAGS}"
+	CPPFLAGS="-I${srcdir} -I${srcdir}/rdma-core/${ibverbs_pabi_version} -Iinclude -I${srcdir}/rdma-core/${ibverbs_pabi_version}/rdma ${CPPFLAGS}"
 	AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include <infiniband/driver.h>]],
 					 [verbs_init_and_alloc_context@{:@@:}@;])],
 	[[# No-argument case is invalid and means we didn't find a prototype]]
 	[dpdk_cv_func_verbs_init_and_alloc_context=no],
 	[AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include <infiniband/driver.h>]],
-					 [[struct foo { struct verbs_context bar; } *baz; verbs_init_and_alloc_context@{:@NULL, NULL, baz, bar, 0@:}@;]])],
+					 [[struct foo { struct verbs_context bar; } *baz; verbs_init_and_alloc_context@{:@NULL, 0, baz, bar, 0@:}@;]])],
 	[dpdk_cv_func_verbs_init_and_alloc_context=5],
 	[AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include <infiniband/driver.h>]],
 					 [[struct foo { struct verbs_context bar; } *baz; verbs_init_and_alloc_context@{:@NULL, NULL, baz, bar@:}@;]])],
@@ -94,6 +94,13 @@ AC_DEFINE_UNQUOTED([IBVERBS_PABI_VERSION], [${ibverbs_pabi_version}],
 		   [Define to rdma-core private ABI version])
 AC_SUBST([ibverbs_pabi_version])
 
+if test $ibverbs_pabi_version -ge 18; then
+	mkdir -p include/kernel-abi
+	${srcdir}/config/make_abi_structs.py \
+		${srcdir}/rdma-core/${ibverbs_pabi_version}/rdma/ib_user_verbs.h \
+		include/kernel-abi/ib_user_verbs.h
+	CPPFLAGS="${CPPFLAGS} -Iinclude"
+fi
 if test $ibverbs_pabi_version -ge 17; then
 	_URDMA_FUNC_VERBS_INIT_AND_ALLOC_CONTEXT
 fi