From: Johannes Berg <johannes.b...@intel.com>
There's no need to have struct bpf_map_type_list since
it just contains a list_head, the type, and the ops
pointer. Since the types are densely packed and not
actually dynamically registered, it's much easier and
smaller to have an array of type->ops pointer. Also
initialize this array statically to remove code needed
to initialize it.
Signed-off-by: Johannes Berg <johannes.b...@intel.com>
---
include/linux/bpf.h | 18 +++++++++------
kernel/bpf/arraymap.c | 64 ++++-----------------------------------------------
kernel/bpf/hashtab.c | 38 ++++--------------------------
kernel/bpf/lpm_trie.c | 14 +----------
kernel/bpf/stackmap.c | 14 +----------
kernel/bpf/syscall.c | 42 ++++++++++++++++++---------------
6 files changed, 46 insertions(+), 144 deletions(-)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 75cea2890751..4a95a25186e5 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -51,12 +51,6 @@ struct bpf_map {
atomic_t usercnt;
};
-struct bpf_map_type_list {
- struct list_head list_node;
- const struct bpf_map_ops *ops;
- enum bpf_map_type type;
-};
-
/* function argument constraints */
enum bpf_arg_type {
ARG_DONTCARE = 0, /* unused argument in helper function */
@@ -239,7 +233,17 @@ extern const struct bpf_verifier_ops kprobe_prog_ops;
extern const struct bpf_verifier_ops tracepoint_prog_ops;
extern const struct bpf_verifier_ops perf_event_prog_ops;
-void bpf_register_map_type(struct bpf_map_type_list *tl);
+extern const struct bpf_map_ops array_map_ops;
+extern const struct bpf_map_ops percpu_array_map_ops;
+extern const struct bpf_map_ops prog_array_map_ops;
+extern const struct bpf_map_ops perf_event_array_map_ops;
+extern const struct bpf_map_ops cgroup_array_map_ops;
+extern const struct bpf_map_ops htab_map_ops;
+extern const struct bpf_map_ops htab_lru_map_ops;
+extern const struct bpf_map_ops htab_percpu_map_ops;
+extern const struct bpf_map_ops htab_lru_percpu_map_ops;
+extern const struct bpf_map_ops trie_map_ops;
+extern const struct bpf_map_ops stack_map_ops;
struct bpf_prog *bpf_prog_get(u32 ufd);
struct bpf_prog *bpf_prog_get_type(u32 ufd, enum bpf_prog_type type);
diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c
index 6b6f41f0b211..376afd14cf32 100644
--- a/kernel/bpf/arraymap.c
+++ b/kernel/bpf/arraymap.c
@@ -260,7 +260,7 @@ static void array_map_free(struct bpf_map *map)
bpf_map_area_free(array);
}
-static const struct bpf_map_ops array_ops = {
+const struct bpf_map_ops array_map_ops = {
.map_alloc = array_map_alloc,
.map_free = array_map_free,
.map_get_next_key = array_map_get_next_key,
@@ -269,12 +269,7 @@ static const struct bpf_map_ops array_ops = {
.map_delete_elem = array_map_delete_elem,
};
-static struct bpf_map_type_list array_type __ro_after_init = {
- .ops = &array_ops,
- .type = BPF_MAP_TYPE_ARRAY,
-};
-
-static const struct bpf_map_ops percpu_array_ops = {
+const struct bpf_map_ops percpu_array_map_ops = {
.map_alloc = array_map_alloc,
.map_free = array_map_free,
.map_get_next_key = array_map_get_next_key,
@@ -283,19 +278,6 @@ static const struct bpf_map_ops percpu_array_ops = {
.map_delete_elem = array_map_delete_elem,
};
-static struct bpf_map_type_list percpu_array_type __ro_after_init = {
- .ops = &percpu_array_ops,
- .type = BPF_MAP_TYPE_PERCPU_ARRAY,
-};
-
-static int __init register_array_map(void)
-{
- bpf_register_map_type(&array_type);
- bpf_register_map_type(&percpu_array_type);
- return 0;
-}
-late_initcall(register_array_map);
-
static struct bpf_map *fd_array_map_alloc(union bpf_attr *attr)
{
/* only file descriptors can be stored in this type of map */
@@ -399,7 +381,7 @@ void bpf_fd_array_map_clear(struct bpf_map *map)
fd_array_map_delete_elem(map, &i);
}
-static const struct bpf_map_ops prog_array_ops = {
+const struct bpf_map_ops prog_array_map_ops = {
.map_alloc = fd_array_map_alloc,
.map_free = fd_array_map_free,
.map_get_next_key = array_map_get_next_key,
@@ -409,18 +391,6 @@ static const struct bpf_map_ops prog_array_ops = {
.map_fd_put_ptr = prog_fd_array_put_ptr,
};
-static struct bpf_map_type_list prog_array_type __ro_after_init = {
- .ops = &prog_array_ops,
- .type = BPF_MAP_TYPE_PROG_ARRAY,
-};
-
-static int __init register_prog_array_map(void)
-{
- bpf_register_map_type(&prog_array_type);
- return 0;
-}
-late_initcall(register_prog_array_map);
-
static struct bpf_event_entry *bpf_event_entry_gen(struct file *perf_file,
struct file *map_file)
{
@@ -511,7 +481,7 @@ static void perf_event_fd_array_release(struct bpf_map *map,
rcu_read_unlock();
}
-static const struct bpf_map_ops perf_event_array_ops = {
+const struct bpf_map_ops perf_event_array_map_ops = {
.map_alloc = fd_array_map_alloc,
.map_free = fd_array_map_free,
.map_get_next_key = array_map_get_next_key,
@@ -522,18 +492,6 @@ static const struct bpf_map_ops perf_event_array_ops = {
.map_release = perf_event_fd_array_release,
};
-static struct bpf_map_type_list perf_event_array_type __ro_after_init = {
- .ops = &perf_event_array_ops,
- .type = BPF_MAP_TYPE_PERF_EVENT_ARRAY,
-};
-
-static int __init register_perf_event_array_map(void)
-{
- bpf_register_map_type(&perf_event_array_type);
- return 0;
-}
-late_initcall(register_perf_event_array_map);
-
#ifdef CONFIG_CGROUPS
static void *cgroup_fd_array_get_ptr(struct bpf_map *map,
struct file *map_file /* not used */,
@@ -554,7 +512,7 @@ static void cgroup_fd_array_free(struct bpf_map *map)
fd_array_map_free(map);
}
-static const struct bpf_map_ops cgroup_array_ops = {
+const struct bpf_map_ops cgroup_array_map_ops = {
.map_alloc = fd_array_map_alloc,
.map_free = cgroup_fd_array_free,
.map_get_next_key = array_map_get_next_key,
@@ -563,16 +521,4 @@ static const struct bpf_map_ops cgroup_array_ops = {
.map_fd_get_ptr = cgroup_fd_array_get_ptr,
.map_fd_put_ptr = cgroup_fd_array_put_ptr,
};
-
-static struct bpf_map_type_list cgroup_array_type __ro_after_init = {
- .ops = &cgroup_array_ops,
- .type = BPF_MAP_TYPE_CGROUP_ARRAY,
-};
-
-static int __init register_cgroup_array_map(void)
-{
- bpf_register_map_type(&cgroup_array_type);
- return 0;
-}
-late_initcall(register_cgroup_array_map);
#endif
diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c
index 3ea87fb19a94..c7913d2aa8ba 100644
--- a/kernel/bpf/hashtab.c
+++ b/kernel/bpf/hashtab.c
@@ -1014,7 +1014,7 @@ static void htab_map_free(struct bpf_map *map)
kfree(htab);
}
-static const struct bpf_map_ops htab_ops = {
+const struct bpf_map_ops htab_map_ops = {
.map_alloc = htab_map_alloc,
.map_free = htab_map_free,
.map_get_next_key = htab_map_get_next_key,
@@ -1023,12 +1023,7 @@ static const struct bpf_map_ops htab_ops = {
.map_delete_elem = htab_map_delete_elem,
};
-static struct bpf_map_type_list htab_type __ro_after_init = {
- .ops = &htab_ops,
- .type = BPF_MAP_TYPE_HASH,
-};
-
-static const struct bpf_map_ops htab_lru_ops = {
+const struct bpf_map_ops htab_lru_map_ops = {
.map_alloc = htab_map_alloc,
.map_free = htab_map_free,
.map_get_next_key = htab_map_get_next_key,
@@ -1037,11 +1032,6 @@ static const struct bpf_map_ops htab_lru_ops = {
.map_delete_elem = htab_lru_map_delete_elem,
};
-static struct bpf_map_type_list htab_lru_type __ro_after_init = {
- .ops = &htab_lru_ops,
- .type = BPF_MAP_TYPE_LRU_HASH,
-};
-
/* Called from eBPF program */
static void *htab_percpu_map_lookup_elem(struct bpf_map *map, void *key)
{
@@ -1115,7 +1105,7 @@ int bpf_percpu_hash_update(struct bpf_map *map, void
*key, void *value,
return ret;
}
-static const struct bpf_map_ops htab_percpu_ops = {
+const struct bpf_map_ops htab_percpu_map_ops = {
.map_alloc = htab_map_alloc,
.map_free = htab_map_free,
.map_get_next_key = htab_map_get_next_key,
@@ -1124,12 +1114,7 @@ static const struct bpf_map_ops htab_percpu_ops = {
.map_delete_elem = htab_map_delete_elem,
};
-static struct bpf_map_type_list htab_percpu_type __ro_after_init = {
- .ops = &htab_percpu_ops,
- .type = BPF_MAP_TYPE_PERCPU_HASH,
-};
-
-static const struct bpf_map_ops htab_lru_percpu_ops = {
+const struct bpf_map_ops htab_lru_percpu_map_ops = {
.map_alloc = htab_map_alloc,
.map_free = htab_map_free,
.map_get_next_key = htab_map_get_next_key,
@@ -1137,18 +1122,3 @@ static const struct bpf_map_ops htab_lru_percpu_ops = {
.map_update_elem = htab_lru_percpu_map_update_elem,
.map_delete_elem = htab_lru_map_delete_elem,
};
-
-static struct bpf_map_type_list htab_lru_percpu_type __ro_after_init = {
- .ops = &htab_lru_percpu_ops,
- .type = BPF_MAP_TYPE_LRU_PERCPU_HASH,
-};
-
-static int __init register_htab_map(void)
-{
- bpf_register_map_type(&htab_type);
- bpf_register_map_type(&htab_percpu_type);
- bpf_register_map_type(&htab_lru_type);
- bpf_register_map_type(&htab_lru_percpu_type);
- return 0;
-}
-late_initcall(register_htab_map);
diff --git a/kernel/bpf/lpm_trie.c b/kernel/bpf/lpm_trie.c
index 8bfe0afaee10..352ae2a2830a 100644
--- a/kernel/bpf/lpm_trie.c
+++ b/kernel/bpf/lpm_trie.c
@@ -500,22 +500,10 @@ static void trie_free(struct bpf_map *map)
raw_spin_unlock(&trie->lock);
}
-static const struct bpf_map_ops trie_ops = {
+const struct bpf_map_ops trie_map_ops = {
.map_alloc = trie_alloc,
.map_free = trie_free,
.map_lookup_elem = trie_lookup_elem,
.map_update_elem = trie_update_elem,
.map_delete_elem = trie_delete_elem,
};
-
-static struct bpf_map_type_list trie_type __ro_after_init = {
- .ops = &trie_ops,
- .type = BPF_MAP_TYPE_LPM_TRIE,
-};
-
-static int __init register_trie_map(void)
-{
- bpf_register_map_type(&trie_type);
- return 0;
-}
-late_initcall(register_trie_map);
diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c
index 22aa45cd0324..4dfd6f2ec2f9 100644
--- a/kernel/bpf/stackmap.c
+++ b/kernel/bpf/stackmap.c
@@ -264,7 +264,7 @@ static void stack_map_free(struct bpf_map *map)
put_callchain_buffers();
}
-static const struct bpf_map_ops stack_map_ops = {
+const struct bpf_map_ops stack_map_ops = {
.map_alloc = stack_map_alloc,
.map_free = stack_map_free,
.map_get_next_key = stack_map_get_next_key,
@@ -272,15 +272,3 @@ static const struct bpf_map_ops stack_map_ops = {
.map_update_elem = stack_map_update_elem,
.map_delete_elem = stack_map_delete_elem,
};
-
-static struct bpf_map_type_list stack_map_type __ro_after_init = {
- .ops = &stack_map_ops,
- .type = BPF_MAP_TYPE_STACK_TRACE,
-};
-
-static int __init register_stack_map(void)
-{
- bpf_register_map_type(&stack_map_type);
- return 0;
-}
-late_initcall(register_stack_map);
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 421aa81ef5d4..c0c02667e641 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -27,30 +27,36 @@ DEFINE_PER_CPU(int, bpf_prog_active);
int sysctl_unprivileged_bpf_disabled __read_mostly;
-static LIST_HEAD(bpf_map_types);
+static const struct bpf_map_ops * const bpf_map_types[] = {
+ [BPF_MAP_TYPE_ARRAY] = &array_map_ops,
+ [BPF_MAP_TYPE_PERCPU_ARRAY] = &percpu_array_map_ops,
+ [BPF_MAP_TYPE_PROG_ARRAY] = &prog_array_map_ops,
+ [BPF_MAP_TYPE_PERF_EVENT_ARRAY] = &perf_event_array_map_ops,
+#ifdef CONFIG_CGROUPS
+ [BPF_MAP_TYPE_CGROUP_ARRAY] = &cgroup_array_map_ops,
+#endif
+ [BPF_MAP_TYPE_HASH] = &htab_map_ops,
+ [BPF_MAP_TYPE_PERCPU_HASH] = &htab_percpu_map_ops,
+ [BPF_MAP_TYPE_LRU_HASH] = &htab_lru_map_ops,
+ [BPF_MAP_TYPE_LRU_PERCPU_HASH] = &htab_lru_percpu_map_ops,
+ [BPF_MAP_TYPE_LPM_TRIE] = &trie_map_ops,
+ [BPF_MAP_TYPE_STACK_TRACE] = &stack_map_ops,
+};
static struct bpf_map *find_and_alloc_map(union bpf_attr *attr)
{
- struct bpf_map_type_list *tl;
struct bpf_map *map;
- list_for_each_entry(tl, &bpf_map_types, list_node) {
- if (tl->type == attr->map_type) {
- map = tl->ops->map_alloc(attr);
- if (IS_ERR(map))
- return map;
- map->ops = tl->ops;
- map->map_type = attr->map_type;
- return map;
- }
- }
- return ERR_PTR(-EINVAL);
-}
+ if (attr->map_type >= ARRAY_SIZE(bpf_map_types) ||
+ !bpf_map_types[attr->map_type])
+ return ERR_PTR(-EINVAL);
-/* boot time registration of different map implementations */
-void bpf_register_map_type(struct bpf_map_type_list *tl)
-{
- list_add(&tl->list_node, &bpf_map_types);
+ map = bpf_map_types[attr->map_type]->map_alloc(attr);
+ if (IS_ERR(map))
+ return map;
+ map->ops = bpf_map_types[attr->map_type];
+ map->map_type = attr->map_type;
+ return map;
}
void *bpf_map_area_alloc(size_t size)
--
2.11.0
