forked from Minki/linux
2beee5f574
We're going to extend this with further information which is only relevant for prog array at this point. Given this info is not used in critical path, move it into its own structure such that the main array map structure can be kept on diet. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/b9ddccdb0f6f7026489ee955f16c96381e1e7238.1574452833.git.daniel@iogearbox.net
120 lines
3.0 KiB
C
120 lines
3.0 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/* Copyright (c) 2017 Facebook
|
|
*/
|
|
#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;
|
|
u32 inner_map_meta_size;
|
|
struct fd f;
|
|
|
|
f = fdget(inner_map_ufd);
|
|
inner_map = __bpf_map_get(f);
|
|
if (IS_ERR(inner_map))
|
|
return inner_map;
|
|
|
|
/* prog_array->aux->{type,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);
|
|
}
|
|
|
|
if (map_value_has_spin_lock(inner_map)) {
|
|
fdput(f);
|
|
return ERR_PTR(-ENOTSUPP);
|
|
}
|
|
|
|
inner_map_meta_size = sizeof(*inner_map_meta);
|
|
/* In some cases verifier needs to access beyond just base map. */
|
|
if (inner_map->ops == &array_map_ops)
|
|
inner_map_meta_size = sizeof(struct bpf_array);
|
|
|
|
inner_map_meta = kzalloc(inner_map_meta_size, 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->max_entries = inner_map->max_entries;
|
|
inner_map_meta->spin_lock_off = inner_map->spin_lock_off;
|
|
|
|
/* Misc members not needed in bpf_map_meta_equal() check. */
|
|
inner_map_meta->ops = inner_map->ops;
|
|
if (inner_map->ops == &array_map_ops) {
|
|
inner_map_meta->unpriv_array = inner_map->unpriv_array;
|
|
container_of(inner_map_meta, struct bpf_array, map)->index_mask =
|
|
container_of(inner_map, struct bpf_array, map)->index_mask;
|
|
}
|
|
|
|
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))
|
|
bpf_map_inc(inner_map);
|
|
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;
|
|
}
|