diff options
Diffstat (limited to 'kernel/bpf/arraymap.c')
| -rw-r--r-- | kernel/bpf/arraymap.c | 137 | 
1 files changed, 106 insertions, 31 deletions
diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c index cb31229a6fa4..29ace107f236 100644 --- a/kernel/bpf/arraymap.c +++ b/kernel/bpf/arraymap.c @@ -150,15 +150,15 @@ static int __init register_array_map(void)  }  late_initcall(register_array_map); -static struct bpf_map *prog_array_map_alloc(union bpf_attr *attr) +static struct bpf_map *fd_array_map_alloc(union bpf_attr *attr)  { -	/* only bpf_prog file descriptors can be stored in prog_array map */ +	/* only file descriptors can be stored in this type of map */  	if (attr->value_size != sizeof(u32))  		return ERR_PTR(-EINVAL);  	return array_map_alloc(attr);  } -static void prog_array_map_free(struct bpf_map *map) +static void fd_array_map_free(struct bpf_map *map)  {  	struct bpf_array *array = container_of(map, struct bpf_array, map);  	int i; @@ -167,21 +167,21 @@ static void prog_array_map_free(struct bpf_map *map)  	/* make sure it's empty */  	for (i = 0; i < array->map.max_entries; i++) -		BUG_ON(array->prog[i] != NULL); +		BUG_ON(array->ptrs[i] != NULL);  	kvfree(array);  } -static void *prog_array_map_lookup_elem(struct bpf_map *map, void *key) +static void *fd_array_map_lookup_elem(struct bpf_map *map, void *key)  {  	return NULL;  }  /* only called from syscall */ -static int prog_array_map_update_elem(struct bpf_map *map, void *key, -				      void *value, u64 map_flags) +static int fd_array_map_update_elem(struct bpf_map *map, void *key, +				    void *value, u64 map_flags)  {  	struct bpf_array *array = container_of(map, struct bpf_array, map); -	struct bpf_prog *prog, *old_prog; +	void *new_ptr, *old_ptr;  	u32 index = *(u32 *)key, ufd;  	if (map_flags != BPF_ANY) @@ -191,57 +191,75 @@ static int prog_array_map_update_elem(struct bpf_map *map, void *key,  		return -E2BIG;  	ufd = *(u32 *)value; -	prog = bpf_prog_get(ufd); -	if (IS_ERR(prog)) -		return PTR_ERR(prog); - -	if (!bpf_prog_array_compatible(array, prog)) { -		bpf_prog_put(prog); -		return -EINVAL; -	} +	new_ptr = map->ops->map_fd_get_ptr(map, ufd); +	if (IS_ERR(new_ptr)) +		return PTR_ERR(new_ptr); -	old_prog = xchg(array->prog + index, prog); -	if (old_prog) -		bpf_prog_put_rcu(old_prog); +	old_ptr = xchg(array->ptrs + index, new_ptr); +	if (old_ptr) +		map->ops->map_fd_put_ptr(old_ptr);  	return 0;  } -static int prog_array_map_delete_elem(struct bpf_map *map, void *key) +static int fd_array_map_delete_elem(struct bpf_map *map, void *key)  {  	struct bpf_array *array = container_of(map, struct bpf_array, map); -	struct bpf_prog *old_prog; +	void *old_ptr;  	u32 index = *(u32 *)key;  	if (index >= array->map.max_entries)  		return -E2BIG; -	old_prog = xchg(array->prog + index, NULL); -	if (old_prog) { -		bpf_prog_put_rcu(old_prog); +	old_ptr = xchg(array->ptrs + index, NULL); +	if (old_ptr) { +		map->ops->map_fd_put_ptr(old_ptr);  		return 0;  	} else {  		return -ENOENT;  	}  } +static void *prog_fd_array_get_ptr(struct bpf_map *map, int fd) +{ +	struct bpf_array *array = container_of(map, struct bpf_array, map); +	struct bpf_prog *prog = bpf_prog_get(fd); +	if (IS_ERR(prog)) +		return prog; + +	if (!bpf_prog_array_compatible(array, prog)) { +		bpf_prog_put(prog); +		return ERR_PTR(-EINVAL); +	} +	return prog; +} + +static void prog_fd_array_put_ptr(void *ptr) +{ +	struct bpf_prog *prog = ptr; + +	bpf_prog_put_rcu(prog); +} +  /* decrement refcnt of all bpf_progs that are stored in this map */ -void bpf_prog_array_map_clear(struct bpf_map *map) +void bpf_fd_array_map_clear(struct bpf_map *map)  {  	struct bpf_array *array = container_of(map, struct bpf_array, map);  	int i;  	for (i = 0; i < array->map.max_entries; i++) -		prog_array_map_delete_elem(map, &i); +		fd_array_map_delete_elem(map, &i);  }  static const struct bpf_map_ops prog_array_ops = { -	.map_alloc = prog_array_map_alloc, -	.map_free = prog_array_map_free, +	.map_alloc = fd_array_map_alloc, +	.map_free = fd_array_map_free,  	.map_get_next_key = array_map_get_next_key, -	.map_lookup_elem = prog_array_map_lookup_elem, -	.map_update_elem = prog_array_map_update_elem, -	.map_delete_elem = prog_array_map_delete_elem, +	.map_lookup_elem = fd_array_map_lookup_elem, +	.map_update_elem = fd_array_map_update_elem, +	.map_delete_elem = fd_array_map_delete_elem, +	.map_fd_get_ptr = prog_fd_array_get_ptr, +	.map_fd_put_ptr = prog_fd_array_put_ptr,  };  static struct bpf_map_type_list prog_array_type __read_mostly = { @@ -255,3 +273,60 @@ static int __init register_prog_array_map(void)  	return 0;  }  late_initcall(register_prog_array_map); + +static void perf_event_array_map_free(struct bpf_map *map) +{ +	bpf_fd_array_map_clear(map); +	fd_array_map_free(map); +} + +static void *perf_event_fd_array_get_ptr(struct bpf_map *map, int fd) +{ +	struct perf_event *event; +	const struct perf_event_attr *attr; + +	event = perf_event_get(fd); +	if (IS_ERR(event)) +		return event; + +	attr = perf_event_attrs(event); +	if (IS_ERR(attr)) +		return (void *)attr; + +	if (attr->type != PERF_TYPE_RAW && +	    attr->type != PERF_TYPE_HARDWARE) { +		perf_event_release_kernel(event); +		return ERR_PTR(-EINVAL); +	} +	return event; +} + +static void perf_event_fd_array_put_ptr(void *ptr) +{ +	struct perf_event *event = ptr; + +	perf_event_release_kernel(event); +} + +static const struct bpf_map_ops perf_event_array_ops = { +	.map_alloc = fd_array_map_alloc, +	.map_free = perf_event_array_map_free, +	.map_get_next_key = array_map_get_next_key, +	.map_lookup_elem = fd_array_map_lookup_elem, +	.map_update_elem = fd_array_map_update_elem, +	.map_delete_elem = fd_array_map_delete_elem, +	.map_fd_get_ptr = perf_event_fd_array_get_ptr, +	.map_fd_put_ptr = perf_event_fd_array_put_ptr, +}; + +static struct bpf_map_type_list perf_event_array_type __read_mostly = { +	.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);  | 
