/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
+ * Copyright (c) 2016,2017 Facebook
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public
#include <linux/filter.h>
#include <linux/perf_event.h>
+#include "map_in_map.h"
+
static void bpf_array_free_percpu(struct bpf_array *array)
{
int i;
return array->value + array->elem_size * index;
}
+/* emit BPF instructions equivalent to C code of array_map_lookup_elem() */
+static u32 array_map_gen_lookup(struct bpf_map *map, struct bpf_insn *insn_buf)
+{
+ struct bpf_insn *insn = insn_buf;
+ u32 elem_size = round_up(map->value_size, 8);
+ const int ret = BPF_REG_0;
+ const int map_ptr = BPF_REG_1;
+ const int index = BPF_REG_2;
+
+ *insn++ = BPF_ALU64_IMM(BPF_ADD, map_ptr, offsetof(struct bpf_array, value));
+ *insn++ = BPF_LDX_MEM(BPF_W, ret, index, 0);
+ *insn++ = BPF_JMP_IMM(BPF_JGE, ret, map->max_entries, 3);
+
+ if (is_power_of_2(elem_size)) {
+ *insn++ = BPF_ALU64_IMM(BPF_LSH, ret, ilog2(elem_size));
+ } else {
+ *insn++ = BPF_ALU64_IMM(BPF_MUL, ret, elem_size);
+ }
+ *insn++ = BPF_ALU64_REG(BPF_ADD, ret, map_ptr);
+ *insn++ = BPF_JMP_IMM(BPF_JA, 0, 0, 1);
+ *insn++ = BPF_MOV64_IMM(ret, 0);
+ return insn - insn_buf;
+}
+
/* Called from eBPF program */
static void *percpu_array_map_lookup_elem(struct bpf_map *map, void *key)
{
static int array_map_get_next_key(struct bpf_map *map, void *key, void *next_key)
{
struct bpf_array *array = container_of(map, struct bpf_array, map);
- u32 index = *(u32 *)key;
+ u32 index = key ? *(u32 *)key : U32_MAX;
u32 *next = (u32 *)next_key;
if (index >= array->map.max_entries) {
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,
.map_lookup_elem = array_map_lookup_elem,
.map_update_elem = array_map_update_elem,
.map_delete_elem = array_map_delete_elem,
+ .map_gen_lookup = array_map_gen_lookup,
};
-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,
.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 */
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,
.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)
{
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,
.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 */,
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,
.map_fd_get_ptr = cgroup_fd_array_get_ptr,
.map_fd_put_ptr = cgroup_fd_array_put_ptr,
};
+#endif
-static struct bpf_map_type_list cgroup_array_type __ro_after_init = {
- .ops = &cgroup_array_ops,
- .type = BPF_MAP_TYPE_CGROUP_ARRAY,
-};
+static struct bpf_map *array_of_map_alloc(union bpf_attr *attr)
+{
+ struct bpf_map *map, *inner_map_meta;
+
+ inner_map_meta = bpf_map_meta_alloc(attr->inner_map_fd);
+ if (IS_ERR(inner_map_meta))
+ return inner_map_meta;
-static int __init register_cgroup_array_map(void)
+ map = fd_array_map_alloc(attr);
+ if (IS_ERR(map)) {
+ bpf_map_meta_free(inner_map_meta);
+ return map;
+ }
+
+ map->inner_map_meta = inner_map_meta;
+
+ return map;
+}
+
+static void array_of_map_free(struct bpf_map *map)
{
- bpf_register_map_type(&cgroup_array_type);
- return 0;
+ /* map->inner_map_meta is only accessed by syscall which
+ * is protected by fdget/fdput.
+ */
+ bpf_map_meta_free(map->inner_map_meta);
+ bpf_fd_array_map_clear(map);
+ fd_array_map_free(map);
}
-late_initcall(register_cgroup_array_map);
-#endif
+
+static void *array_of_map_lookup_elem(struct bpf_map *map, void *key)
+{
+ struct bpf_map **inner_map = array_map_lookup_elem(map, key);
+
+ if (!inner_map)
+ return NULL;
+
+ return READ_ONCE(*inner_map);
+}
+
+const struct bpf_map_ops array_of_maps_map_ops = {
+ .map_alloc = array_of_map_alloc,
+ .map_free = array_of_map_free,
+ .map_get_next_key = array_map_get_next_key,
+ .map_lookup_elem = array_of_map_lookup_elem,
+ .map_delete_elem = fd_array_map_delete_elem,
+ .map_fd_get_ptr = bpf_map_fd_get_ptr,
+ .map_fd_put_ptr = bpf_map_fd_put_ptr,
+};
projects / platform / kernel / linux-rpi.git / blobdiff