ebpf: constify various function pointer structs

We can move bpf_map_ops and bpf_verifier_ops and other structs into ro
section, bpf_map_type_list and bpf_prog_type_list into read mostly.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 9 insertions, 9 deletions

diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c
index 9eb4d8a..8a66165 100644
--- a/kernel/bpf/arraymap.c
+++ b/kernel/bpf/arraymap.c
@@ -134,7 +134,7 @@ static void array_map_free(struct bpf_map *map)
 	kvfree(array);
 }
 
-static struct bpf_map_ops array_ops = {
+static const struct bpf_map_ops array_ops = {
 	.map_alloc = array_map_alloc,
 	.map_free = array_map_free,
 	.map_get_next_key = array_map_get_next_key,
@@ -143,14 +143,14 @@ static struct bpf_map_ops array_ops = {
 	.map_delete_elem = array_map_delete_elem,
 };
 
-static struct bpf_map_type_list tl = {
+static struct bpf_map_type_list array_type __read_mostly = {
 	.ops = &array_ops,
 	.type = BPF_MAP_TYPE_ARRAY,
 };
 
 static int __init register_array_map(void)
 {
-	bpf_register_map_type(&tl);
+	bpf_register_map_type(&array_type);
 	return 0;
 }
 late_initcall(register_array_map);
diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c
index b3ba436..83c209d 100644
--- a/kernel/bpf/hashtab.c
+++ b/kernel/bpf/hashtab.c
@@ -345,7 +345,7 @@ static void htab_map_free(struct bpf_map *map)
 	kfree(htab);
 }
 
-static struct bpf_map_ops htab_ops = {
+static const struct bpf_map_ops htab_ops = {
 	.map_alloc = htab_map_alloc,
 	.map_free = htab_map_free,
 	.map_get_next_key = htab_map_get_next_key,
@@ -354,14 +354,14 @@ static struct bpf_map_ops htab_ops = {
 	.map_delete_elem = htab_map_delete_elem,
 };
 
-static struct bpf_map_type_list tl = {
+static struct bpf_map_type_list htab_type __read_mostly = {
 	.ops = &htab_ops,
 	.type = BPF_MAP_TYPE_HASH,
 };
 
 static int __init register_htab_map(void)
 {
-	bpf_register_map_type(&tl);
+	bpf_register_map_type(&htab_type);
 	return 0;
 }
 late_initcall(register_htab_map);
diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
index 9e3414d..a3c7701 100644
--- a/kernel/bpf/helpers.c
+++ b/kernel/bpf/helpers.c
@@ -41,7 +41,7 @@ static u64 bpf_map_lookup_elem(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
 	return (unsigned long) value;
 }
 
-struct bpf_func_proto bpf_map_lookup_elem_proto = {
+const struct bpf_func_proto bpf_map_lookup_elem_proto = {
 	.func = bpf_map_lookup_elem,
 	.gpl_only = false,
 	.ret_type = RET_PTR_TO_MAP_VALUE_OR_NULL,
@@ -60,7 +60,7 @@ static u64 bpf_map_update_elem(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
 	return map->ops->map_update_elem(map, key, value, r4);
 }
 
-struct bpf_func_proto bpf_map_update_elem_proto = {
+const struct bpf_func_proto bpf_map_update_elem_proto = {
 	.func = bpf_map_update_elem,
 	.gpl_only = false,
 	.ret_type = RET_INTEGER,
@@ -80,7 +80,7 @@ static u64 bpf_map_delete_elem(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
 	return map->ops->map_delete_elem(map, key);
 }
 
-struct bpf_func_proto bpf_map_delete_elem_proto = {
+const struct bpf_func_proto bpf_map_delete_elem_proto = {
 	.func = bpf_map_delete_elem,
 	.gpl_only = false,
 	.ret_type = RET_INTEGER,