compat: Fix broken partial backport of extack op parameter

A series of commits added support for the extended ack
parameter to the newlink, changelink and validate ops in
the rtnl_link_ops structure:
a8b8a889e369d ("net: add netlink_ext_ack argument to rtnl_link_ops.validate")
7a3f4a185169b ("net: add netlink_ext_ack argument to rtnl_link_ops.newlink")
ad744b223c521 ("net: add netlink_ext_ack argument to rtnl_link_ops.changelink")

These commits were all added at the same time and present since the
Linux kernel 4.13 release. In our compatiblity layer we have a
define HAVE_EXT_ACK_IN_RTNL_LINKOPS that indicates the presence of
the extended ack parameter for these three link operations.

At least one distro has only backported two of the three patches,
for newlink and changelink, while not backporting patch a8b8a889e369d
for the validate op.  Our compatibility layer code in acinclude.m4
is able to find the presence of the extack within the rtnl_link_ops
structure so it defines HAVE_EXT_ACK_IN_RTNL_LINKOPS but since the
validate link op does not have the extack parameter the compilation
fails on recent kernels for that particular distro. Other kernel
distributions based upon this distro will presumably also encounter
the compile errors.

Introduce a new function in acinclude.m4 that will find function
op definitions and then search for the required parameter.  Then
use this function to define HAVE_RTNLOP_VALIDATE_WITH_EXTACK so
that we can detect and enable correct compilation on kernels
which have not backported the entire set of patches.  This function
is generic to any function op - it need not be in a structure.

In places where HAVE_EXT_ACK_IN_RTNL_LINKOPS wraps validate functions
replace it with the new HAVE_RTNLOP_VALIDATE_WITH_EXTACK define.

Passes Travis here:
https://travis-ci.org/github/gvrose8192/ovs-experimental/builds/674599698

Passes a kernel check-kmod test on several systems, including
sles12 sp4 4.12.14-95.48-default kernel, without any regressions.

VMWare-BZ: #2544032
Signed-off-by: Greg Rose <gvrose8192@gmail.com>
Reviewed-by: Yifeng Sun <pkusunyifeng@gmail.com>
Signed-off-by: William Tu <u9012063@gmail.com>

diff --git a/acinclude.m4 b/acinclude.m4
index 02efea6de2fe07f3ca1ff41f52c2af48070d2f78..0901f28702397f060094e51530ceea6433dc350d 100644 (file)
--- a/acinclude.m4
+++ b/acinclude.m4
@@ -520,6 +520,37 @@ AC_DEFUN([OVS_FIND_PARAM_IFELSE], [
   fi
 ])
 
+dnl OVS_FIND_OP_PARAM_IFELSE(FILE, OP, REGEX, [IF-MATCH], [IF-NO-MATCH])
+dnl
+dnl Looks for OP in FILE. If it is found, greps for REGEX within the
+dnl OP definition. If this is successful, runs IF-MATCH, otherwise
+dnl IF_NO_MATCH. If IF-MATCH is empty then it defines to
+dnl OVS_DEFINE(HAVE_<OP>_WITH_<REGEX>), with <OP> and <REGEX>
+dnl translated to uppercase.
+AC_DEFUN([OVS_FIND_OP_PARAM_IFELSE], [
+  AC_MSG_CHECKING([whether $2 has member $3 in $1])
+  if test -f $1; then
+    awk '/$2[[ \t\n]]*\)\(/,/;/' $1 2>/dev/null | grep '$3' >/dev/null
+    status=$?
+    case $status in
+      0)
+        AC_MSG_RESULT([yes])
+        m4_if([$4], [], [OVS_DEFINE([HAVE_]m4_toupper([$2])[_WITH_]m4_toupper([$3]))], [$4])
+        ;;
+      1)
+        AC_MSG_RESULT([no])
+        $5
+        ;;
+      *)
+        AC_MSG_ERROR([grep exited with status $status])
+        ;;
+    esac
+  else
+    AC_MSG_RESULT([file not found])
+    $5
+  fi
+])
+
 dnl OVS_DEFINE(NAME)
 dnl
 dnl Defines NAME to 1 in kcompat.h.
@@ -1056,6 +1087,9 @@ AC_DEFUN([OVS_CHECK_LINUX_COMPAT], [
   OVS_GREP_IFELSE([$KSRC/include/net/netlink.h],
                   [nla_parse_deprecated_strict],
                   [OVS_DEFINE([HAVE_NLA_PARSE_DEPRECATED_STRICT])])
+  OVS_FIND_OP_PARAM_IFELSE([$KSRC/include/net/rtnetlink.h],
+                           [validate], [extack],
+                           [OVS_DEFINE([HAVE_RTNLOP_VALIDATE_WITH_EXTACK])])
 
   if cmp -s datapath/linux/kcompat.h.new \
             datapath/linux/kcompat.h >/dev/null 2>&1; then

diff --git a/datapath/linux/compat/geneve.c b/datapath/linux/compat/geneve.c
index 5b183963d637884902439a87a66598b687ffcee5..1551a37217ec8b24a82645a51f08759576a6da97 100644 (file)
--- a/datapath/linux/compat/geneve.c
+++ b/datapath/linux/compat/geneve.c
@@ -1419,7 +1419,7 @@ static const struct nla_policy geneve_policy[IFLA_GENEVE_MAX + 1] = {
        [IFLA_GENEVE_UDP_ZERO_CSUM6_RX] = { .type = NLA_U8 },
 };
 
-#ifdef  HAVE_EXT_ACK_IN_RTNL_LINKOPS
+#ifdef  HAVE_RTNLOP_VALIDATE_WITH_EXTACK
 static int geneve_validate(struct nlattr *tb[], struct nlattr *data[],
                           struct netlink_ext_ack *extack)
 #else

diff --git a/datapath/linux/compat/ip6_gre.c b/datapath/linux/compat/ip6_gre.c
index da0fa432b8247297540e1a5bf5759c35351700f2..3aa9844b370c4a7b05ae87e9e5e82732a976a535 100644 (file)
--- a/datapath/linux/compat/ip6_gre.c
+++ b/datapath/linux/compat/ip6_gre.c
@@ -1687,7 +1687,7 @@ static struct pernet_operations ip6gre_net_ops = {
        .id   = &ip6gre_net_id,
        .size = sizeof(struct ip6gre_net),
 };
-#ifdef HAVE_EXT_ACK_IN_RTNL_LINKOPS
+#ifdef HAVE_RTNLOP_VALIDATE_WITH_EXTACK
 static int rpl_ip6gre_tunnel_validate(struct nlattr *tb[],
                                      struct nlattr *data[],
                                      struct netlink_ext_ack *extack)
@@ -1713,7 +1713,7 @@ static int rpl_ip6gre_tunnel_validate(struct nlattr *tb[],
 }
 #define ip6gre_tunnel_validate rpl_ip6gre_tunnel_validate
 
-#ifdef HAVE_EXT_ACK_IN_RTNL_LINKOPS
+#ifdef HAVE_RTNLOP_VALIDATE_WITH_EXTACK
 static int rpl_ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[],
                                   struct netlink_ext_ack *extack)
 #else
@@ -1739,7 +1739,7 @@ static int rpl_ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[])
        }
 
 out:
-#ifdef HAVE_EXT_ACK_IN_RTNL_LINKOPS
+#ifdef HAVE_RTNLOP_VALIDATE_WITH_EXTACK
        return ip6gre_tunnel_validate(tb, data, extack);
 #else
        return ip6gre_tunnel_validate(tb, data);
@@ -1747,7 +1747,7 @@ out:
 }
 #define ip6gre_tap_validate rpl_ip6gre_tap_validate
 
-#ifdef HAVE_EXT_ACK_IN_RTNL_LINKOPS
+#ifdef HAVE_RTNLOP_VALIDATE_WITH_EXTACK
 static int rpl_ip6erspan_tap_validate(struct nlattr *tb[],
                                      struct nlattr *data[],
                                      struct netlink_ext_ack *extack)
@@ -1762,7 +1762,7 @@ static int rpl_ip6erspan_tap_validate(struct nlattr *tb[],
        if (!data)
                return 0;
 
-#ifdef HAVE_EXT_ACK_IN_RTNL_LINKOPS
+#ifdef HAVE_RTNLOP_VALIDATE_WITH_EXTACK
        ret = ip6gre_tap_validate(tb, data, extack);
 #else
        ret = ip6gre_tap_validate(tb, data);

diff --git a/datapath/linux/compat/ip6_tunnel.c b/datapath/linux/compat/ip6_tunnel.c
index 9f4bae7dd3d1406499e58fdd8c37570884822ae2..984a51bfb942d2dd80843ac20b926c976f7d7189 100644 (file)
--- a/datapath/linux/compat/ip6_tunnel.c
+++ b/datapath/linux/compat/ip6_tunnel.c
@@ -1754,7 +1754,7 @@ static int __net_init ip6_fb_tnl_dev_init(struct net_device *dev)
        return 0;
 }
 
-#ifdef HAVE_EXT_ACK_IN_RTNL_LINKOPS
+#ifdef HAVE_RTNLOP_VALIDATE_WITH_EXTACK
 static int rpl_ip6_tnl_validate(struct nlattr *tb[], struct nlattr *data[],
                                struct netlink_ext_ack *extack)
 #else

diff --git a/datapath/linux/compat/ip_gre.c b/datapath/linux/compat/ip_gre.c
index 41379b19a0467f92ab62ee2790edec8439273ec9..c194ffe0064453b271cb11b3c01fa4806ec6f986 100644 (file)
--- a/datapath/linux/compat/ip_gre.c
+++ b/datapath/linux/compat/ip_gre.c
@@ -623,7 +623,7 @@ static const struct gre_protocol ipgre_protocol = {
        .err_handler = __gre_err,
 };
 
-#ifdef HAVE_EXT_ACK_IN_RTNL_LINKOPS
+#ifdef HAVE_RTNLOP_VALIDATE_WITH_EXTACK
 static int ipgre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[],
                                 struct netlink_ext_ack *extack)
 #else
@@ -646,7 +646,7 @@ static int ipgre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[])
        return 0;
 }
 
-#ifdef HAVE_EXT_ACK_IN_RTNL_LINKOPS
+#ifdef HAVE_RTNLOP_VALIDATE_WITH_EXTACK
 static int ipgre_tap_validate(struct nlattr *tb[], struct nlattr *data[],
                              struct netlink_ext_ack *extack)
 #else
@@ -672,7 +672,7 @@ static int ipgre_tap_validate(struct nlattr *tb[], struct nlattr *data[])
        }
 
 out:
-#ifdef HAVE_EXT_ACK_IN_RTNL_LINKOPS
+#ifdef HAVE_RTNLOP_VALIDATE_WITH_EXTACK
        return ipgre_tunnel_validate(tb, data, NULL);
 #else
        return ipgre_tunnel_validate(tb, data);
@@ -707,7 +707,7 @@ enum {
 
 #define RPL_IFLA_GRE_MAX (IFLA_GRE_ERSPAN_HWID + 1)
 
-#ifdef HAVE_EXT_ACK_IN_RTNL_LINKOPS
+#ifdef HAVE_RTNLOP_VALIDATE_WITH_EXTACK
 static int erspan_validate(struct nlattr *tb[], struct nlattr *data[],
                           struct netlink_ext_ack *extack)
 #else
@@ -720,7 +720,7 @@ static int erspan_validate(struct nlattr *tb[], struct nlattr *data[])
        if (!data)
                return 0;
 
-#ifdef HAVE_EXT_ACK_IN_RTNL_LINKOPS
+#ifdef HAVE_RTNLOP_VALIDATE_WITH_EXTACK
        ret = ipgre_tap_validate(tb, data, NULL);
 #else
        ret = ipgre_tap_validate(tb, data);

diff --git a/datapath/linux/compat/lisp.c b/datapath/linux/compat/lisp.c
index 58144adf6a363ccd932c5496d54628a55b4b4a50..6dc066de8ebb977a0ea4a60cd2706433e8689af1 100644 (file)
--- a/datapath/linux/compat/lisp.c
+++ b/datapath/linux/compat/lisp.c
@@ -612,7 +612,7 @@ static const struct nla_policy lisp_policy[IFLA_LISP_MAX + 1] = {
        [IFLA_LISP_PORT]              = { .type = NLA_U16 },
 };
 
-#ifdef HAVE_EXT_ACK_IN_RTNL_LINKOPS
+#ifdef HAVE_RTNLOP_VALIDATE_WITH_EXTACK
 static int lisp_validate(struct nlattr *tb[], struct nlattr *data[],
                         struct netlink_ext_ack __always_unused *extack)
 #else

diff --git a/datapath/linux/compat/stt.c b/datapath/linux/compat/stt.c
index 8a5853f1934cbc2d0dc4be7240c64531a38ca29a..39a294764ec8fb053b5360fb813c61a2f6392571 100644 (file)
--- a/datapath/linux/compat/stt.c
+++ b/datapath/linux/compat/stt.c
@@ -1904,7 +1904,7 @@ static const struct nla_policy stt_policy[IFLA_STT_MAX + 1] = {
        [IFLA_STT_PORT]              = { .type = NLA_U16 },
 };
 
-#ifdef HAVE_EXT_ACK_IN_RTNL_LINKOPS
+#ifdef HAVE_RTNLOP_VALIDATE_WITH_EXTACK
 static int stt_validate(struct nlattr *tb[], struct nlattr *data[],
                        struct netlink_ext_ack __always_unused *extack)
 #else

diff --git a/datapath/linux/compat/vxlan.c b/datapath/linux/compat/vxlan.c
index 6090f429095c395fa7087b2303f921f62f9159d4..f8f667e9748b5918b1a496407252e38631e70024 100644 (file)
--- a/datapath/linux/compat/vxlan.c
+++ b/datapath/linux/compat/vxlan.c
@@ -1708,7 +1708,7 @@ static const struct nla_policy vxlan_policy[IFLA_VXLAN_MAX + 1] = {
        [IFLA_VXLAN_REMCSUM_NOPARTIAL]  = { .type = NLA_FLAG },
 };
 
-#ifdef HAVE_EXT_ACK_IN_RTNL_LINKOPS
+#ifdef HAVE_RTNLOP_VALIDATE_WITH_EXTACK
 static int vxlan_validate(struct nlattr *tb[], struct nlattr *data[],
                          struct netlink_ext_ack *extack)
 #else