From acebffb966ddfedbc9e2a73f47940fefbdfeed73 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Maciej=20=C5=BBenczykowski?= <maze@google.com>
Date: Mon, 16 May 2022 16:05:15 -0700
Subject: [PATCH] add proper minimum bpfloader version annotations for
 block/clatd/dscp_policy/netd
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In practice this doesn't actually really matter, since older versions
of the bpfloader won't even look in the relevant directories:

BpfLoader v0.9 is the first one that looks into
  '/apex/com.android.tethering/etc/bpf/net_shared',
but it is only v0.12 that pins the resulting programs and maps
correctly into
  /sys/fs/bpf/net_shared/
hence the annotations for block/clatd/dscp_policy.

BpfLoader v0.13 is the first one that looks into
  '/apex/com.android.tethering/etc/bpf/netd_shared'
subdirectory and pins into
  /sys/fs/bpf/netd_shared/
hence the annotation for netd.

But it's best to explicitly document the intent.

Note that in practice the mainline module will fail spectacularly
on a T OS if it can't find the programs and maps
(presumably due to the bpfloader being too old)
but will work on S even though the bpfloader there is much older,
because these programs/maps are not required on pre-T OS.

This change is thus really only documentation.

Bug: 218408035
Test: TreeHugger
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: I5ffa2faf83ca337b84e34b01df84436629989c58
---
 bpf_progs/block.c       | 3 +++
 bpf_progs/clatd.c       | 3 +++
 bpf_progs/dscp_policy.c | 3 +++
 bpf_progs/netd.c        | 3 +++
 4 files changed, 12 insertions(+)

diff --git a/bpf_progs/block.c b/bpf_progs/block.c
index ddd9a1cbed..601b93281e 100644
--- a/bpf_progs/block.c
+++ b/bpf_progs/block.c
@@ -19,6 +19,9 @@
 #include <netinet/in.h>
 #include <stdint.h>
 
+// The resulting .o needs to load on the Android T bpfloader v0.12+
+#define BPFLOADER_MIN_VER 12u
+
 #include "bpf_helpers.h"
 
 #define ALLOW 1
diff --git a/bpf_progs/clatd.c b/bpf_progs/clatd.c
index 9a9d3373dc..87795f58ad 100644
--- a/bpf_progs/clatd.c
+++ b/bpf_progs/clatd.c
@@ -30,6 +30,9 @@
 #define __kernel_udphdr udphdr
 #include <linux/udp.h>
 
+// The resulting .o needs to load on the Android T bpfloader v0.12+
+#define BPFLOADER_MIN_VER 12u
+
 #include "bpf_helpers.h"
 #include "bpf_net_helpers.h"
 #include "bpf_shared.h"
diff --git a/bpf_progs/dscp_policy.c b/bpf_progs/dscp_policy.c
index d5df7ef6ba..7211f2b866 100644
--- a/bpf_progs/dscp_policy.c
+++ b/bpf_progs/dscp_policy.c
@@ -27,6 +27,9 @@
 #include <netinet/udp.h>
 #include <string.h>
 
+// The resulting .o needs to load on the Android T bpfloader v0.12+
+#define BPFLOADER_MIN_VER 12u
+
 #include "bpf_helpers.h"
 #include "dscp_policy.h"
 
diff --git a/bpf_progs/netd.c b/bpf_progs/netd.c
index f3f675fb87..e484010256 100644
--- a/bpf_progs/netd.c
+++ b/bpf_progs/netd.c
@@ -14,6 +14,9 @@
  * limitations under the License.
  */
 
+// The resulting .o needs to load on the Android T Beta 3 bpfloader v0.13+
+#define BPFLOADER_MIN_VER 13u
+
 #include <bpf_helpers.h>
 #include <linux/bpf.h>
 #include <linux/if.h>