commit 36c53ba91e54ac2786aa2bd4865970dc42dbe04d
author Maciej Żenczykowski <maze@google.com> Mon Jul 05 15:20:34 2021 -0700
committer Maciej Żenczykowski <maze@google.com> Mon Jul 05 18:02:16 2021 -0700
tree 3a8021a617e59df89614369eed5ea479ae040794
parent df91d2b5b265849eb59fea3721a0d68f4f77edfe

bpf - struct bpf_map_def - add min/max kernel version.

This is also bpfloader v0.2.
Some newer map types (for example DEVMAP) are unusable
on older kernel versions.

Bug: 190519702
Test: atest, TreeHugger
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: I085cc723ff1c19d8acc8972a391f894e16dd1875

progs/include/bpf_helpers.h

diff --git a/progs/include/bpf_helpers.h b/progs/include/bpf_helpers.h
index 6e5fe69..abd19c6 100644
--- a/progs/include/bpf_helpers.h
+++ b/progs/include/bpf_helpers.h
@@ -59,6 +59,10 @@
  * implemented in the kernel sources.
  */
 
+#define KVER_NONE 0
+#define KVER(a, b, c) (((a) << 24) + ((b) << 16) + (c))
+#define KVER_INF 0xFFFFFFFFu
+
 /* generic functions */
 
 /*
@@ -110,6 +114,8 @@
             .mode = (md),                                                                        \
             .bpfloader_min_ver = DEFAULT_BPFLOADER_MIN_VER,                                      \
             .bpfloader_max_ver = DEFAULT_BPFLOADER_MAX_VER,                                      \
+            .min_kver = KVER_NONE,                                                               \
+            .max_kver = KVER_INF,                                                                \
     };                                                                                           \
                                                                                                  \
     static inline __always_inline __unused TypeOfValue* bpf_##the_map##_lookup_elem(             \
@@ -147,10 +153,6 @@
 static unsigned long long (*bpf_get_current_uid_gid)(void) = (void*) BPF_FUNC_get_current_uid_gid;
 static unsigned long long (*bpf_get_smp_processor_id)(void) = (void*) BPF_FUNC_get_smp_processor_id;
 
-#define KVER_NONE 0
-#define KVER(a, b, c) (((a) << 24) + ((b) << 16) + (c))
-#define KVER_INF 0xFFFFFFFF
-
 #define DEFINE_BPF_PROG_KVER_RANGE_OPT(SECTION_NAME, prog_uid, prog_gid, the_prog, min_kv, max_kv, \
                                        opt)                                                        \
     const struct bpf_prog_def SEC("progs") the_prog##_def = {                                      \

progs/include/bpf_map_def.h

diff --git a/progs/include/bpf_map_def.h b/progs/include/bpf_map_def.h
index f51b1c4..647c813 100644
--- a/progs/include/bpf_map_def.h
+++ b/progs/include/bpf_map_def.h
@@ -141,10 +141,15 @@
     // The following fields were added in version 0.1
     unsigned int bpfloader_min_ver;  // if missing, defaults to 0, ie. v0.0
     unsigned int bpfloader_max_ver;  // if missing, defaults to 0x10000, ie. v1.0
+
+    // The following fields were added in version 0.2
+    // kernelVersion() must be >= min_kver and < max_kver
+    unsigned int min_kver;
+    unsigned int max_kver;
 };
 
 // This needs to be updated whenever the above structure definition is expanded.
-_Static_assert(sizeof(struct bpf_map_def) == 40, "sizeof struct bpf_map_def != 40");
+_Static_assert(sizeof(struct bpf_map_def) == 48, "sizeof struct bpf_map_def != 48");
 _Static_assert(__alignof__(struct bpf_map_def) == 4, "__alignof__ struct bpf_map_def != 4");
 _Static_assert(_Alignof(struct bpf_map_def) == 4, "_Alignof struct bpf_map_def != 4");
 
@@ -162,6 +167,8 @@
     // The following fields were added in version 0.1
     unsigned int bpfloader_min_ver;  // if missing, defaults to 0, ie. v0.0
     unsigned int bpfloader_max_ver;  // if missing, defaults to 0x10000, ie. v1.0
+
+    // No new fields in version 0.2
 };
 
 // This needs to be updated whenever the above structure definition is expanded.