105 lines
2.5 KiB
C
105 lines
2.5 KiB
C
/* Copyright (c) 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
|
|
* License as published by the Free Software Foundation.
|
|
*/
|
|
#include <linux/slab.h>
|
|
#include <linux/bpf.h>
|
|
|
|
#include "map_in_map.h"
|
|
|
|
struct bpf_map *bpf_map_meta_alloc(int inner_map_ufd)
|
|
{
|
|
struct bpf_map *inner_map, *inner_map_meta;
|
|
struct fd f;
|
|
|
|
f = fdget(inner_map_ufd);
|
|
inner_map = __bpf_map_get(f);
|
|
if (IS_ERR(inner_map))
|
|
return inner_map;
|
|
|
|
/* prog_array->owner_prog_type and owner_jited
|
|
* is a runtime binding. Doing static check alone
|
|
* in the verifier is not enough.
|
|
*/
|
|
if (inner_map->map_type == BPF_MAP_TYPE_PROG_ARRAY ||
|
|
inner_map->map_type == BPF_MAP_TYPE_CGROUP_STORAGE ||
|
|
inner_map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) {
|
|
fdput(f);
|
|
return ERR_PTR(-ENOTSUPP);
|
|
}
|
|
|
|
/* Does not support >1 level map-in-map */
|
|
if (inner_map->inner_map_meta) {
|
|
fdput(f);
|
|
return ERR_PTR(-EINVAL);
|
|
}
|
|
|
|
inner_map_meta = kzalloc(sizeof(*inner_map_meta), GFP_USER);
|
|
if (!inner_map_meta) {
|
|
fdput(f);
|
|
return ERR_PTR(-ENOMEM);
|
|
}
|
|
|
|
inner_map_meta->map_type = inner_map->map_type;
|
|
inner_map_meta->key_size = inner_map->key_size;
|
|
inner_map_meta->value_size = inner_map->value_size;
|
|
inner_map_meta->map_flags = inner_map->map_flags;
|
|
inner_map_meta->ops = inner_map->ops;
|
|
inner_map_meta->max_entries = inner_map->max_entries;
|
|
|
|
fdput(f);
|
|
return inner_map_meta;
|
|
}
|
|
|
|
void bpf_map_meta_free(struct bpf_map *map_meta)
|
|
{
|
|
kfree(map_meta);
|
|
}
|
|
|
|
bool bpf_map_meta_equal(const struct bpf_map *meta0,
|
|
const struct bpf_map *meta1)
|
|
{
|
|
/* No need to compare ops because it is covered by map_type */
|
|
return meta0->map_type == meta1->map_type &&
|
|
meta0->key_size == meta1->key_size &&
|
|
meta0->value_size == meta1->value_size &&
|
|
meta0->map_flags == meta1->map_flags &&
|
|
meta0->max_entries == meta1->max_entries;
|
|
}
|
|
|
|
void *bpf_map_fd_get_ptr(struct bpf_map *map,
|
|
struct file *map_file /* not used */,
|
|
int ufd)
|
|
{
|
|
struct bpf_map *inner_map;
|
|
struct fd f;
|
|
|
|
f = fdget(ufd);
|
|
inner_map = __bpf_map_get(f);
|
|
if (IS_ERR(inner_map))
|
|
return inner_map;
|
|
|
|
if (bpf_map_meta_equal(map->inner_map_meta, inner_map))
|
|
inner_map = bpf_map_inc(inner_map, false);
|
|
else
|
|
inner_map = ERR_PTR(-EINVAL);
|
|
|
|
fdput(f);
|
|
return inner_map;
|
|
}
|
|
|
|
void bpf_map_fd_put_ptr(void *ptr)
|
|
{
|
|
/* ptr->ops->map_free() has to go through one
|
|
* rcu grace period by itself.
|
|
*/
|
|
bpf_map_put(ptr);
|
|
}
|
|
|
|
u32 bpf_map_fd_sys_lookup_elem(void *ptr)
|
|
{
|
|
return ((struct bpf_map *)ptr)->id;
|
|
}
|