mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-25 02:09:42 +00:00
![David S. Miller](/assets/img/avatar_default.png)
Honestly all the conflicts were simple overlapping changes, nothing really interesting to report. Signed-off-by: David S. Miller <davem@davemloft.net>
846 lines
22 KiB
C
846 lines
22 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
|
|
* Copyright (c) 2016,2017 Facebook
|
|
*/
|
|
#include <linux/bpf.h>
|
|
#include <linux/btf.h>
|
|
#include <linux/err.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/filter.h>
|
|
#include <linux/perf_event.h>
|
|
#include <uapi/linux/btf.h>
|
|
|
|
#include "map_in_map.h"
|
|
|
|
#define ARRAY_CREATE_FLAG_MASK \
|
|
(BPF_F_NUMA_NODE | BPF_F_ACCESS_MASK)
|
|
|
|
static void bpf_array_free_percpu(struct bpf_array *array)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < array->map.max_entries; i++) {
|
|
free_percpu(array->pptrs[i]);
|
|
cond_resched();
|
|
}
|
|
}
|
|
|
|
static int bpf_array_alloc_percpu(struct bpf_array *array)
|
|
{
|
|
void __percpu *ptr;
|
|
int i;
|
|
|
|
for (i = 0; i < array->map.max_entries; i++) {
|
|
ptr = __alloc_percpu_gfp(array->elem_size, 8,
|
|
GFP_USER | __GFP_NOWARN);
|
|
if (!ptr) {
|
|
bpf_array_free_percpu(array);
|
|
return -ENOMEM;
|
|
}
|
|
array->pptrs[i] = ptr;
|
|
cond_resched();
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Called from syscall */
|
|
int array_map_alloc_check(union bpf_attr *attr)
|
|
{
|
|
bool percpu = attr->map_type == BPF_MAP_TYPE_PERCPU_ARRAY;
|
|
int numa_node = bpf_map_attr_numa_node(attr);
|
|
|
|
/* check sanity of attributes */
|
|
if (attr->max_entries == 0 || attr->key_size != 4 ||
|
|
attr->value_size == 0 ||
|
|
attr->map_flags & ~ARRAY_CREATE_FLAG_MASK ||
|
|
!bpf_map_flags_access_ok(attr->map_flags) ||
|
|
(percpu && numa_node != NUMA_NO_NODE))
|
|
return -EINVAL;
|
|
|
|
if (attr->value_size > KMALLOC_MAX_SIZE)
|
|
/* if value_size is bigger, the user space won't be able to
|
|
* access the elements.
|
|
*/
|
|
return -E2BIG;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct bpf_map *array_map_alloc(union bpf_attr *attr)
|
|
{
|
|
bool percpu = attr->map_type == BPF_MAP_TYPE_PERCPU_ARRAY;
|
|
int ret, numa_node = bpf_map_attr_numa_node(attr);
|
|
u32 elem_size, index_mask, max_entries;
|
|
bool unpriv = !capable(CAP_SYS_ADMIN);
|
|
u64 cost, array_size, mask64;
|
|
struct bpf_map_memory mem;
|
|
struct bpf_array *array;
|
|
|
|
elem_size = round_up(attr->value_size, 8);
|
|
|
|
max_entries = attr->max_entries;
|
|
|
|
/* On 32 bit archs roundup_pow_of_two() with max_entries that has
|
|
* upper most bit set in u32 space is undefined behavior due to
|
|
* resulting 1U << 32, so do it manually here in u64 space.
|
|
*/
|
|
mask64 = fls_long(max_entries - 1);
|
|
mask64 = 1ULL << mask64;
|
|
mask64 -= 1;
|
|
|
|
index_mask = mask64;
|
|
if (unpriv) {
|
|
/* round up array size to nearest power of 2,
|
|
* since cpu will speculate within index_mask limits
|
|
*/
|
|
max_entries = index_mask + 1;
|
|
/* Check for overflows. */
|
|
if (max_entries < attr->max_entries)
|
|
return ERR_PTR(-E2BIG);
|
|
}
|
|
|
|
array_size = sizeof(*array);
|
|
if (percpu)
|
|
array_size += (u64) max_entries * sizeof(void *);
|
|
else
|
|
array_size += (u64) max_entries * elem_size;
|
|
|
|
/* make sure there is no u32 overflow later in round_up() */
|
|
cost = array_size;
|
|
if (percpu)
|
|
cost += (u64)attr->max_entries * elem_size * num_possible_cpus();
|
|
|
|
ret = bpf_map_charge_init(&mem, cost);
|
|
if (ret < 0)
|
|
return ERR_PTR(ret);
|
|
|
|
/* allocate all map elements and zero-initialize them */
|
|
array = bpf_map_area_alloc(array_size, numa_node);
|
|
if (!array) {
|
|
bpf_map_charge_finish(&mem);
|
|
return ERR_PTR(-ENOMEM);
|
|
}
|
|
array->index_mask = index_mask;
|
|
array->map.unpriv_array = unpriv;
|
|
|
|
/* copy mandatory map attributes */
|
|
bpf_map_init_from_attr(&array->map, attr);
|
|
bpf_map_charge_move(&array->map.memory, &mem);
|
|
array->elem_size = elem_size;
|
|
|
|
if (percpu && bpf_array_alloc_percpu(array)) {
|
|
bpf_map_charge_finish(&array->map.memory);
|
|
bpf_map_area_free(array);
|
|
return ERR_PTR(-ENOMEM);
|
|
}
|
|
|
|
return &array->map;
|
|
}
|
|
|
|
/* Called from syscall or from eBPF program */
|
|
static void *array_map_lookup_elem(struct bpf_map *map, void *key)
|
|
{
|
|
struct bpf_array *array = container_of(map, struct bpf_array, map);
|
|
u32 index = *(u32 *)key;
|
|
|
|
if (unlikely(index >= array->map.max_entries))
|
|
return NULL;
|
|
|
|
return array->value + array->elem_size * (index & array->index_mask);
|
|
}
|
|
|
|
static int array_map_direct_value_addr(const struct bpf_map *map, u64 *imm,
|
|
u32 off)
|
|
{
|
|
struct bpf_array *array = container_of(map, struct bpf_array, map);
|
|
|
|
if (map->max_entries != 1)
|
|
return -ENOTSUPP;
|
|
if (off >= map->value_size)
|
|
return -EINVAL;
|
|
|
|
*imm = (unsigned long)array->value;
|
|
return 0;
|
|
}
|
|
|
|
static int array_map_direct_value_meta(const struct bpf_map *map, u64 imm,
|
|
u32 *off)
|
|
{
|
|
struct bpf_array *array = container_of(map, struct bpf_array, map);
|
|
u64 base = (unsigned long)array->value;
|
|
u64 range = array->elem_size;
|
|
|
|
if (map->max_entries != 1)
|
|
return -ENOTSUPP;
|
|
if (imm < base || imm >= base + range)
|
|
return -ENOENT;
|
|
|
|
*off = imm - base;
|
|
return 0;
|
|
}
|
|
|
|
/* 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_array *array = container_of(map, struct bpf_array, map);
|
|
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);
|
|
if (map->unpriv_array) {
|
|
*insn++ = BPF_JMP_IMM(BPF_JGE, ret, map->max_entries, 4);
|
|
*insn++ = BPF_ALU32_IMM(BPF_AND, ret, array->index_mask);
|
|
} else {
|
|
*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)
|
|
{
|
|
struct bpf_array *array = container_of(map, struct bpf_array, map);
|
|
u32 index = *(u32 *)key;
|
|
|
|
if (unlikely(index >= array->map.max_entries))
|
|
return NULL;
|
|
|
|
return this_cpu_ptr(array->pptrs[index & array->index_mask]);
|
|
}
|
|
|
|
int bpf_percpu_array_copy(struct bpf_map *map, void *key, void *value)
|
|
{
|
|
struct bpf_array *array = container_of(map, struct bpf_array, map);
|
|
u32 index = *(u32 *)key;
|
|
void __percpu *pptr;
|
|
int cpu, off = 0;
|
|
u32 size;
|
|
|
|
if (unlikely(index >= array->map.max_entries))
|
|
return -ENOENT;
|
|
|
|
/* per_cpu areas are zero-filled and bpf programs can only
|
|
* access 'value_size' of them, so copying rounded areas
|
|
* will not leak any kernel data
|
|
*/
|
|
size = round_up(map->value_size, 8);
|
|
rcu_read_lock();
|
|
pptr = array->pptrs[index & array->index_mask];
|
|
for_each_possible_cpu(cpu) {
|
|
bpf_long_memcpy(value + off, per_cpu_ptr(pptr, cpu), size);
|
|
off += size;
|
|
}
|
|
rcu_read_unlock();
|
|
return 0;
|
|
}
|
|
|
|
/* Called from syscall */
|
|
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 = key ? *(u32 *)key : U32_MAX;
|
|
u32 *next = (u32 *)next_key;
|
|
|
|
if (index >= array->map.max_entries) {
|
|
*next = 0;
|
|
return 0;
|
|
}
|
|
|
|
if (index == array->map.max_entries - 1)
|
|
return -ENOENT;
|
|
|
|
*next = index + 1;
|
|
return 0;
|
|
}
|
|
|
|
/* Called from syscall or from eBPF program */
|
|
static int 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);
|
|
u32 index = *(u32 *)key;
|
|
char *val;
|
|
|
|
if (unlikely((map_flags & ~BPF_F_LOCK) > BPF_EXIST))
|
|
/* unknown flags */
|
|
return -EINVAL;
|
|
|
|
if (unlikely(index >= array->map.max_entries))
|
|
/* all elements were pre-allocated, cannot insert a new one */
|
|
return -E2BIG;
|
|
|
|
if (unlikely(map_flags & BPF_NOEXIST))
|
|
/* all elements already exist */
|
|
return -EEXIST;
|
|
|
|
if (unlikely((map_flags & BPF_F_LOCK) &&
|
|
!map_value_has_spin_lock(map)))
|
|
return -EINVAL;
|
|
|
|
if (array->map.map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
|
|
memcpy(this_cpu_ptr(array->pptrs[index & array->index_mask]),
|
|
value, map->value_size);
|
|
} else {
|
|
val = array->value +
|
|
array->elem_size * (index & array->index_mask);
|
|
if (map_flags & BPF_F_LOCK)
|
|
copy_map_value_locked(map, val, value, false);
|
|
else
|
|
copy_map_value(map, val, value);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
int bpf_percpu_array_update(struct bpf_map *map, void *key, void *value,
|
|
u64 map_flags)
|
|
{
|
|
struct bpf_array *array = container_of(map, struct bpf_array, map);
|
|
u32 index = *(u32 *)key;
|
|
void __percpu *pptr;
|
|
int cpu, off = 0;
|
|
u32 size;
|
|
|
|
if (unlikely(map_flags > BPF_EXIST))
|
|
/* unknown flags */
|
|
return -EINVAL;
|
|
|
|
if (unlikely(index >= array->map.max_entries))
|
|
/* all elements were pre-allocated, cannot insert a new one */
|
|
return -E2BIG;
|
|
|
|
if (unlikely(map_flags == BPF_NOEXIST))
|
|
/* all elements already exist */
|
|
return -EEXIST;
|
|
|
|
/* the user space will provide round_up(value_size, 8) bytes that
|
|
* will be copied into per-cpu area. bpf programs can only access
|
|
* value_size of it. During lookup the same extra bytes will be
|
|
* returned or zeros which were zero-filled by percpu_alloc,
|
|
* so no kernel data leaks possible
|
|
*/
|
|
size = round_up(map->value_size, 8);
|
|
rcu_read_lock();
|
|
pptr = array->pptrs[index & array->index_mask];
|
|
for_each_possible_cpu(cpu) {
|
|
bpf_long_memcpy(per_cpu_ptr(pptr, cpu), value + off, size);
|
|
off += size;
|
|
}
|
|
rcu_read_unlock();
|
|
return 0;
|
|
}
|
|
|
|
/* Called from syscall or from eBPF program */
|
|
static int array_map_delete_elem(struct bpf_map *map, void *key)
|
|
{
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* Called when map->refcnt goes to zero, either from workqueue or from syscall */
|
|
static void array_map_free(struct bpf_map *map)
|
|
{
|
|
struct bpf_array *array = container_of(map, struct bpf_array, map);
|
|
|
|
/* at this point bpf_prog->aux->refcnt == 0 and this map->refcnt == 0,
|
|
* so the programs (can be more than one that used this map) were
|
|
* disconnected from events. Wait for outstanding programs to complete
|
|
* and free the array
|
|
*/
|
|
synchronize_rcu();
|
|
|
|
if (array->map.map_type == BPF_MAP_TYPE_PERCPU_ARRAY)
|
|
bpf_array_free_percpu(array);
|
|
|
|
bpf_map_area_free(array);
|
|
}
|
|
|
|
static void array_map_seq_show_elem(struct bpf_map *map, void *key,
|
|
struct seq_file *m)
|
|
{
|
|
void *value;
|
|
|
|
rcu_read_lock();
|
|
|
|
value = array_map_lookup_elem(map, key);
|
|
if (!value) {
|
|
rcu_read_unlock();
|
|
return;
|
|
}
|
|
|
|
if (map->btf_key_type_id)
|
|
seq_printf(m, "%u: ", *(u32 *)key);
|
|
btf_type_seq_show(map->btf, map->btf_value_type_id, value, m);
|
|
seq_puts(m, "\n");
|
|
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
static void percpu_array_map_seq_show_elem(struct bpf_map *map, void *key,
|
|
struct seq_file *m)
|
|
{
|
|
struct bpf_array *array = container_of(map, struct bpf_array, map);
|
|
u32 index = *(u32 *)key;
|
|
void __percpu *pptr;
|
|
int cpu;
|
|
|
|
rcu_read_lock();
|
|
|
|
seq_printf(m, "%u: {\n", *(u32 *)key);
|
|
pptr = array->pptrs[index & array->index_mask];
|
|
for_each_possible_cpu(cpu) {
|
|
seq_printf(m, "\tcpu%d: ", cpu);
|
|
btf_type_seq_show(map->btf, map->btf_value_type_id,
|
|
per_cpu_ptr(pptr, cpu), m);
|
|
seq_puts(m, "\n");
|
|
}
|
|
seq_puts(m, "}\n");
|
|
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
static int array_map_check_btf(const struct bpf_map *map,
|
|
const struct btf *btf,
|
|
const struct btf_type *key_type,
|
|
const struct btf_type *value_type)
|
|
{
|
|
u32 int_data;
|
|
|
|
/* One exception for keyless BTF: .bss/.data/.rodata map */
|
|
if (btf_type_is_void(key_type)) {
|
|
if (map->map_type != BPF_MAP_TYPE_ARRAY ||
|
|
map->max_entries != 1)
|
|
return -EINVAL;
|
|
|
|
if (BTF_INFO_KIND(value_type->info) != BTF_KIND_DATASEC)
|
|
return -EINVAL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
if (BTF_INFO_KIND(key_type->info) != BTF_KIND_INT)
|
|
return -EINVAL;
|
|
|
|
int_data = *(u32 *)(key_type + 1);
|
|
/* bpf array can only take a u32 key. This check makes sure
|
|
* that the btf matches the attr used during map_create.
|
|
*/
|
|
if (BTF_INT_BITS(int_data) != 32 || BTF_INT_OFFSET(int_data))
|
|
return -EINVAL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
const struct bpf_map_ops array_map_ops = {
|
|
.map_alloc_check = array_map_alloc_check,
|
|
.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,
|
|
.map_direct_value_addr = array_map_direct_value_addr,
|
|
.map_direct_value_meta = array_map_direct_value_meta,
|
|
.map_seq_show_elem = array_map_seq_show_elem,
|
|
.map_check_btf = array_map_check_btf,
|
|
};
|
|
|
|
const struct bpf_map_ops percpu_array_map_ops = {
|
|
.map_alloc_check = array_map_alloc_check,
|
|
.map_alloc = array_map_alloc,
|
|
.map_free = array_map_free,
|
|
.map_get_next_key = array_map_get_next_key,
|
|
.map_lookup_elem = percpu_array_map_lookup_elem,
|
|
.map_update_elem = array_map_update_elem,
|
|
.map_delete_elem = array_map_delete_elem,
|
|
.map_seq_show_elem = percpu_array_map_seq_show_elem,
|
|
.map_check_btf = array_map_check_btf,
|
|
};
|
|
|
|
static int fd_array_map_alloc_check(union bpf_attr *attr)
|
|
{
|
|
/* only file descriptors can be stored in this type of map */
|
|
if (attr->value_size != sizeof(u32))
|
|
return -EINVAL;
|
|
/* Program read-only/write-only not supported for special maps yet. */
|
|
if (attr->map_flags & (BPF_F_RDONLY_PROG | BPF_F_WRONLY_PROG))
|
|
return -EINVAL;
|
|
return array_map_alloc_check(attr);
|
|
}
|
|
|
|
static void fd_array_map_free(struct bpf_map *map)
|
|
{
|
|
struct bpf_array *array = container_of(map, struct bpf_array, map);
|
|
int i;
|
|
|
|
synchronize_rcu();
|
|
|
|
/* make sure it's empty */
|
|
for (i = 0; i < array->map.max_entries; i++)
|
|
BUG_ON(array->ptrs[i] != NULL);
|
|
|
|
bpf_map_area_free(array);
|
|
}
|
|
|
|
static void *fd_array_map_lookup_elem(struct bpf_map *map, void *key)
|
|
{
|
|
return ERR_PTR(-EOPNOTSUPP);
|
|
}
|
|
|
|
/* only called from syscall */
|
|
int bpf_fd_array_map_lookup_elem(struct bpf_map *map, void *key, u32 *value)
|
|
{
|
|
void **elem, *ptr;
|
|
int ret = 0;
|
|
|
|
if (!map->ops->map_fd_sys_lookup_elem)
|
|
return -ENOTSUPP;
|
|
|
|
rcu_read_lock();
|
|
elem = array_map_lookup_elem(map, key);
|
|
if (elem && (ptr = READ_ONCE(*elem)))
|
|
*value = map->ops->map_fd_sys_lookup_elem(ptr);
|
|
else
|
|
ret = -ENOENT;
|
|
rcu_read_unlock();
|
|
|
|
return ret;
|
|
}
|
|
|
|
/* only called from syscall */
|
|
int bpf_fd_array_map_update_elem(struct bpf_map *map, struct file *map_file,
|
|
void *key, void *value, u64 map_flags)
|
|
{
|
|
struct bpf_array *array = container_of(map, struct bpf_array, map);
|
|
void *new_ptr, *old_ptr;
|
|
u32 index = *(u32 *)key, ufd;
|
|
|
|
if (map_flags != BPF_ANY)
|
|
return -EINVAL;
|
|
|
|
if (index >= array->map.max_entries)
|
|
return -E2BIG;
|
|
|
|
ufd = *(u32 *)value;
|
|
new_ptr = map->ops->map_fd_get_ptr(map, map_file, ufd);
|
|
if (IS_ERR(new_ptr))
|
|
return PTR_ERR(new_ptr);
|
|
|
|
old_ptr = xchg(array->ptrs + index, new_ptr);
|
|
if (old_ptr)
|
|
map->ops->map_fd_put_ptr(old_ptr);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int fd_array_map_delete_elem(struct bpf_map *map, void *key)
|
|
{
|
|
struct bpf_array *array = container_of(map, struct bpf_array, map);
|
|
void *old_ptr;
|
|
u32 index = *(u32 *)key;
|
|
|
|
if (index >= array->map.max_entries)
|
|
return -E2BIG;
|
|
|
|
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,
|
|
struct file *map_file, 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)
|
|
{
|
|
bpf_prog_put(ptr);
|
|
}
|
|
|
|
static u32 prog_fd_array_sys_lookup_elem(void *ptr)
|
|
{
|
|
return ((struct bpf_prog *)ptr)->aux->id;
|
|
}
|
|
|
|
/* decrement refcnt of all bpf_progs that are stored in this map */
|
|
static 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++)
|
|
fd_array_map_delete_elem(map, &i);
|
|
}
|
|
|
|
static void prog_array_map_seq_show_elem(struct bpf_map *map, void *key,
|
|
struct seq_file *m)
|
|
{
|
|
void **elem, *ptr;
|
|
u32 prog_id;
|
|
|
|
rcu_read_lock();
|
|
|
|
elem = array_map_lookup_elem(map, key);
|
|
if (elem) {
|
|
ptr = READ_ONCE(*elem);
|
|
if (ptr) {
|
|
seq_printf(m, "%u: ", *(u32 *)key);
|
|
prog_id = prog_fd_array_sys_lookup_elem(ptr);
|
|
btf_type_seq_show(map->btf, map->btf_value_type_id,
|
|
&prog_id, m);
|
|
seq_puts(m, "\n");
|
|
}
|
|
}
|
|
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
const struct bpf_map_ops prog_array_map_ops = {
|
|
.map_alloc_check = fd_array_map_alloc_check,
|
|
.map_alloc = array_map_alloc,
|
|
.map_free = fd_array_map_free,
|
|
.map_get_next_key = array_map_get_next_key,
|
|
.map_lookup_elem = fd_array_map_lookup_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,
|
|
.map_fd_sys_lookup_elem = prog_fd_array_sys_lookup_elem,
|
|
.map_release_uref = bpf_fd_array_map_clear,
|
|
.map_seq_show_elem = prog_array_map_seq_show_elem,
|
|
};
|
|
|
|
static struct bpf_event_entry *bpf_event_entry_gen(struct file *perf_file,
|
|
struct file *map_file)
|
|
{
|
|
struct bpf_event_entry *ee;
|
|
|
|
ee = kzalloc(sizeof(*ee), GFP_ATOMIC);
|
|
if (ee) {
|
|
ee->event = perf_file->private_data;
|
|
ee->perf_file = perf_file;
|
|
ee->map_file = map_file;
|
|
}
|
|
|
|
return ee;
|
|
}
|
|
|
|
static void __bpf_event_entry_free(struct rcu_head *rcu)
|
|
{
|
|
struct bpf_event_entry *ee;
|
|
|
|
ee = container_of(rcu, struct bpf_event_entry, rcu);
|
|
fput(ee->perf_file);
|
|
kfree(ee);
|
|
}
|
|
|
|
static void bpf_event_entry_free_rcu(struct bpf_event_entry *ee)
|
|
{
|
|
call_rcu(&ee->rcu, __bpf_event_entry_free);
|
|
}
|
|
|
|
static void *perf_event_fd_array_get_ptr(struct bpf_map *map,
|
|
struct file *map_file, int fd)
|
|
{
|
|
struct bpf_event_entry *ee;
|
|
struct perf_event *event;
|
|
struct file *perf_file;
|
|
u64 value;
|
|
|
|
perf_file = perf_event_get(fd);
|
|
if (IS_ERR(perf_file))
|
|
return perf_file;
|
|
|
|
ee = ERR_PTR(-EOPNOTSUPP);
|
|
event = perf_file->private_data;
|
|
if (perf_event_read_local(event, &value, NULL, NULL) == -EOPNOTSUPP)
|
|
goto err_out;
|
|
|
|
ee = bpf_event_entry_gen(perf_file, map_file);
|
|
if (ee)
|
|
return ee;
|
|
ee = ERR_PTR(-ENOMEM);
|
|
err_out:
|
|
fput(perf_file);
|
|
return ee;
|
|
}
|
|
|
|
static void perf_event_fd_array_put_ptr(void *ptr)
|
|
{
|
|
bpf_event_entry_free_rcu(ptr);
|
|
}
|
|
|
|
static void perf_event_fd_array_release(struct bpf_map *map,
|
|
struct file *map_file)
|
|
{
|
|
struct bpf_array *array = container_of(map, struct bpf_array, map);
|
|
struct bpf_event_entry *ee;
|
|
int i;
|
|
|
|
rcu_read_lock();
|
|
for (i = 0; i < array->map.max_entries; i++) {
|
|
ee = READ_ONCE(array->ptrs[i]);
|
|
if (ee && ee->map_file == map_file)
|
|
fd_array_map_delete_elem(map, &i);
|
|
}
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
const struct bpf_map_ops perf_event_array_map_ops = {
|
|
.map_alloc_check = fd_array_map_alloc_check,
|
|
.map_alloc = array_map_alloc,
|
|
.map_free = fd_array_map_free,
|
|
.map_get_next_key = array_map_get_next_key,
|
|
.map_lookup_elem = fd_array_map_lookup_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,
|
|
.map_release = perf_event_fd_array_release,
|
|
.map_check_btf = map_check_no_btf,
|
|
};
|
|
|
|
#ifdef CONFIG_CGROUPS
|
|
static void *cgroup_fd_array_get_ptr(struct bpf_map *map,
|
|
struct file *map_file /* not used */,
|
|
int fd)
|
|
{
|
|
return cgroup_get_from_fd(fd);
|
|
}
|
|
|
|
static void cgroup_fd_array_put_ptr(void *ptr)
|
|
{
|
|
/* cgroup_put free cgrp after a rcu grace period */
|
|
cgroup_put(ptr);
|
|
}
|
|
|
|
static void cgroup_fd_array_free(struct bpf_map *map)
|
|
{
|
|
bpf_fd_array_map_clear(map);
|
|
fd_array_map_free(map);
|
|
}
|
|
|
|
const struct bpf_map_ops cgroup_array_map_ops = {
|
|
.map_alloc_check = fd_array_map_alloc_check,
|
|
.map_alloc = array_map_alloc,
|
|
.map_free = cgroup_fd_array_free,
|
|
.map_get_next_key = array_map_get_next_key,
|
|
.map_lookup_elem = fd_array_map_lookup_elem,
|
|
.map_delete_elem = fd_array_map_delete_elem,
|
|
.map_fd_get_ptr = cgroup_fd_array_get_ptr,
|
|
.map_fd_put_ptr = cgroup_fd_array_put_ptr,
|
|
.map_check_btf = map_check_no_btf,
|
|
};
|
|
#endif
|
|
|
|
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;
|
|
|
|
map = 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)
|
|
{
|
|
/* 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);
|
|
}
|
|
|
|
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);
|
|
}
|
|
|
|
static u32 array_of_map_gen_lookup(struct bpf_map *map,
|
|
struct bpf_insn *insn_buf)
|
|
{
|
|
struct bpf_array *array = container_of(map, struct bpf_array, map);
|
|
u32 elem_size = round_up(map->value_size, 8);
|
|
struct bpf_insn *insn = insn_buf;
|
|
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);
|
|
if (map->unpriv_array) {
|
|
*insn++ = BPF_JMP_IMM(BPF_JGE, ret, map->max_entries, 6);
|
|
*insn++ = BPF_ALU32_IMM(BPF_AND, ret, array->index_mask);
|
|
} else {
|
|
*insn++ = BPF_JMP_IMM(BPF_JGE, ret, map->max_entries, 5);
|
|
}
|
|
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_LDX_MEM(BPF_DW, ret, ret, 0);
|
|
*insn++ = BPF_JMP_IMM(BPF_JEQ, ret, 0, 1);
|
|
*insn++ = BPF_JMP_IMM(BPF_JA, 0, 0, 1);
|
|
*insn++ = BPF_MOV64_IMM(ret, 0);
|
|
|
|
return insn - insn_buf;
|
|
}
|
|
|
|
const struct bpf_map_ops array_of_maps_map_ops = {
|
|
.map_alloc_check = fd_array_map_alloc_check,
|
|
.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,
|
|
.map_fd_sys_lookup_elem = bpf_map_fd_sys_lookup_elem,
|
|
.map_gen_lookup = array_of_map_gen_lookup,
|
|
.map_check_btf = map_check_no_btf,
|
|
};
|