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|
// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
/* Copyright (C) 2016-2018 Netronome Systems, Inc. */
/*
* nfp_net_offload.c
* Netronome network device driver: TC offload functions for PF and VF
*/
#define pr_fmt(fmt) "NFP net bpf: " fmt
#include <linux/bpf.h>
#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <linux/pci.h>
#include <linux/jiffies.h>
#include <linux/timer.h>
#include <linux/list.h>
#include <linux/mm.h>
#include <net/pkt_cls.h>
#include <net/tc_act/tc_gact.h>
#include <net/tc_act/tc_mirred.h>
#include "main.h"
#include "../nfp_app.h"
#include "../nfp_net_ctrl.h"
#include "../nfp_net.h"
static int
nfp_map_ptr_record(struct nfp_app_bpf *bpf, struct nfp_prog *nfp_prog,
struct bpf_map *map)
{
struct nfp_bpf_neutral_map *record;
int err;
/* Reuse path - other offloaded program is already tracking this map. */
record = rhashtable_lookup_fast(&bpf->maps_neutral, &map->id,
nfp_bpf_maps_neutral_params);
if (record) {
nfp_prog->map_records[nfp_prog->map_records_cnt++] = record;
record->count++;
return 0;
}
/* Grab a single ref to the map for our record. The prog destroy ndo
* happens after free_used_maps().
*/
map = bpf_map_inc(map, false);
if (IS_ERR(map))
return PTR_ERR(map);
record = kmalloc(sizeof(*record), GFP_KERNEL);
if (!record) {
err = -ENOMEM;
goto err_map_put;
}
record->ptr = map;
record->map_id = map->id;
record->count = 1;
err = rhashtable_insert_fast(&bpf->maps_neutral, &record->l,
nfp_bpf_maps_neutral_params);
if (err)
goto err_free_rec;
nfp_prog->map_records[nfp_prog->map_records_cnt++] = record;
return 0;
err_free_rec:
kfree(record);
err_map_put:
bpf_map_put(map);
return err;
}
static void
nfp_map_ptrs_forget(struct nfp_app_bpf *bpf, struct nfp_prog *nfp_prog)
{
bool freed = false;
int i;
for (i = 0; i < nfp_prog->map_records_cnt; i++) {
if (--nfp_prog->map_records[i]->count) {
nfp_prog->map_records[i] = NULL;
continue;
}
WARN_ON(rhashtable_remove_fast(&bpf->maps_neutral,
&nfp_prog->map_records[i]->l,
nfp_bpf_maps_neutral_params));
freed = true;
}
if (freed) {
synchronize_rcu();
for (i = 0; i < nfp_prog->map_records_cnt; i++)
if (nfp_prog->map_records[i]) {
bpf_map_put(nfp_prog->map_records[i]->ptr);
kfree(nfp_prog->map_records[i]);
}
}
kfree(nfp_prog->map_records);
nfp_prog->map_records = NULL;
nfp_prog->map_records_cnt = 0;
}
static int
nfp_map_ptrs_record(struct nfp_app_bpf *bpf, struct nfp_prog *nfp_prog,
struct bpf_prog *prog)
{
int i, cnt, err;
/* Quickly count the maps we will have to remember */
cnt = 0;
for (i = 0; i < prog->aux->used_map_cnt; i++)
if (bpf_map_offload_neutral(prog->aux->used_maps[i]))
cnt++;
if (!cnt)
return 0;
nfp_prog->map_records = kmalloc_array(cnt,
sizeof(nfp_prog->map_records[0]),
GFP_KERNEL);
if (!nfp_prog->map_records)
return -ENOMEM;
for (i = 0; i < prog->aux->used_map_cnt; i++)
if (bpf_map_offload_neutral(prog->aux->used_maps[i])) {
err = nfp_map_ptr_record(bpf, nfp_prog,
prog->aux->used_maps[i]);
if (err) {
nfp_map_ptrs_forget(bpf, nfp_prog);
return err;
}
}
WARN_ON(cnt != nfp_prog->map_records_cnt);
return 0;
}
static int
nfp_prog_prepare(struct nfp_prog *nfp_prog, const struct bpf_insn *prog,
unsigned int cnt)
{
struct nfp_insn_meta *meta;
unsigned int i;
for (i = 0; i < cnt; i++) {
meta = kzalloc(sizeof(*meta), GFP_KERNEL);
if (!meta)
return -ENOMEM;
meta->insn = prog[i];
meta->n = i;
if (is_mbpf_alu(meta)) {
meta->umin_src = U64_MAX;
meta->umin_dst = U64_MAX;
}
list_add_tail(&meta->l, &nfp_prog->insns);
}
nfp_prog->n_insns = cnt;
nfp_bpf_jit_prepare(nfp_prog);
return 0;
}
static void nfp_prog_free(struct nfp_prog *nfp_prog)
{
struct nfp_insn_meta *meta, *tmp;
kfree(nfp_prog->subprog);
list_for_each_entry_safe(meta, tmp, &nfp_prog->insns, l) {
list_del(&meta->l);
kfree(meta);
}
kfree(nfp_prog);
}
static int nfp_bpf_verifier_prep(struct bpf_prog *prog)
{
struct nfp_net *nn = netdev_priv(prog->aux->offload->netdev);
struct nfp_app *app = nn->app;
struct nfp_prog *nfp_prog;
int ret;
nfp_prog = kzalloc(sizeof(*nfp_prog), GFP_KERNEL);
if (!nfp_prog)
return -ENOMEM;
prog->aux->offload->dev_priv = nfp_prog;
INIT_LIST_HEAD(&nfp_prog->insns);
nfp_prog->type = prog->type;
nfp_prog->bpf = app->priv;
ret = nfp_prog_prepare(nfp_prog, prog->insnsi, prog->len);
if (ret)
goto err_free;
nfp_prog->verifier_meta = nfp_prog_first_meta(nfp_prog);
return 0;
err_free:
nfp_prog_free(nfp_prog);
return ret;
}
static int nfp_bpf_translate(struct bpf_prog *prog)
{
struct nfp_net *nn = netdev_priv(prog->aux->offload->netdev);
struct nfp_prog *nfp_prog = prog->aux->offload->dev_priv;
unsigned int max_instr;
int err;
/* We depend on dead code elimination succeeding */
if (prog->aux->offload->opt_failed)
return -EINVAL;
max_instr = nn_readw(nn, NFP_NET_CFG_BPF_MAX_LEN);
nfp_prog->__prog_alloc_len = max_instr * sizeof(u64);
nfp_prog->prog = kvmalloc(nfp_prog->__prog_alloc_len, GFP_KERNEL);
if (!nfp_prog->prog)
return -ENOMEM;
err = nfp_bpf_jit(nfp_prog);
if (err)
return err;
prog->aux->offload->jited_len = nfp_prog->prog_len * sizeof(u64);
prog->aux->offload->jited_image = nfp_prog->prog;
return nfp_map_ptrs_record(nfp_prog->bpf, nfp_prog, prog);
}
static void nfp_bpf_destroy(struct bpf_prog *prog)
{
struct nfp_prog *nfp_prog = prog->aux->offload->dev_priv;
kvfree(nfp_prog->prog);
nfp_map_ptrs_forget(nfp_prog->bpf, nfp_prog);
nfp_prog_free(nfp_prog);
}
/* Atomic engine requires values to be in big endian, we need to byte swap
* the value words used with xadd.
*/
static void nfp_map_bpf_byte_swap(struct nfp_bpf_map *nfp_map, void *value)
{
u32 *word = value;
unsigned int i;
for (i = 0; i < DIV_ROUND_UP(nfp_map->offmap->map.value_size, 4); i++)
if (nfp_map->use_map[i].type == NFP_MAP_USE_ATOMIC_CNT)
word[i] = (__force u32)cpu_to_be32(word[i]);
}
/* Mark value as unsafely initialized in case it becomes atomic later
* and we didn't byte swap something non-byte swap neutral.
*/
static void
nfp_map_bpf_byte_swap_record(struct nfp_bpf_map *nfp_map, void *value)
{
u32 *word = value;
unsigned int i;
for (i = 0; i < DIV_ROUND_UP(nfp_map->offmap->map.value_size, 4); i++)
if (nfp_map->use_map[i].type == NFP_MAP_UNUSED &&
word[i] != (__force u32)cpu_to_be32(word[i]))
nfp_map->use_map[i].non_zero_update = 1;
}
static int
nfp_bpf_map_lookup_entry(struct bpf_offloaded_map *offmap,
void *key, void *value)
{
int err;
err = nfp_bpf_ctrl_lookup_entry(offmap, key, value);
if (err)
return err;
nfp_map_bpf_byte_swap(offmap->dev_priv, value);
return 0;
}
static int
nfp_bpf_map_update_entry(struct bpf_offloaded_map *offmap,
void *key, void *value, u64 flags)
{
nfp_map_bpf_byte_swap(offmap->dev_priv, value);
nfp_map_bpf_byte_swap_record(offmap->dev_priv, value);
return nfp_bpf_ctrl_update_entry(offmap, key, value, flags);
}
static int
nfp_bpf_map_get_next_key(struct bpf_offloaded_map *offmap,
void *key, void *next_key)
{
if (!key)
return nfp_bpf_ctrl_getfirst_entry(offmap, next_key);
return nfp_bpf_ctrl_getnext_entry(offmap, key, next_key);
}
static int
nfp_bpf_map_delete_elem(struct bpf_offloaded_map *offmap, void *key)
{
if (offmap->map.map_type == BPF_MAP_TYPE_ARRAY)
return -EINVAL;
return nfp_bpf_ctrl_del_entry(offmap, key);
}
static const struct bpf_map_dev_ops nfp_bpf_map_ops = {
.map_get_next_key = nfp_bpf_map_get_next_key,
.map_lookup_elem = nfp_bpf_map_lookup_entry,
.map_update_elem = nfp_bpf_map_update_entry,
.map_delete_elem = nfp_bpf_map_delete_elem,
};
static int
nfp_bpf_map_alloc(struct nfp_app_bpf *bpf, struct bpf_offloaded_map *offmap)
{
struct nfp_bpf_map *nfp_map;
unsigned int use_map_size;
long long int res;
if (!bpf->maps.types)
return -EOPNOTSUPP;
if (offmap->map.map_flags ||
offmap->map.numa_node != NUMA_NO_NODE) {
pr_info("map flags are not supported\n");
return -EINVAL;
}
if (!(bpf->maps.types & 1 << offmap->map.map_type)) {
pr_info("map type not supported\n");
return -EOPNOTSUPP;
}
if (bpf->maps.max_maps == bpf->maps_in_use) {
pr_info("too many maps for a device\n");
return -ENOMEM;
}
if (bpf->maps.max_elems - bpf->map_elems_in_use <
offmap->map.max_entries) {
pr_info("map with too many elements: %u, left: %u\n",
offmap->map.max_entries,
bpf->maps.max_elems - bpf->map_elems_in_use);
return -ENOMEM;
}
if (round_up(offmap->map.key_size, 8) +
round_up(offmap->map.value_size, 8) > bpf->maps.max_elem_sz) {
pr_info("map elements too large: %u, FW max element size (key+value): %u\n",
round_up(offmap->map.key_size, 8) +
round_up(offmap->map.value_size, 8),
bpf->maps.max_elem_sz);
return -ENOMEM;
}
if (offmap->map.key_size > bpf->maps.max_key_sz) {
pr_info("map key size %u, FW max is %u\n",
offmap->map.key_size, bpf->maps.max_key_sz);
return -ENOMEM;
}
if (offmap->map.value_size > bpf->maps.max_val_sz) {
pr_info("map value size %u, FW max is %u\n",
offmap->map.value_size, bpf->maps.max_val_sz);
return -ENOMEM;
}
use_map_size = DIV_ROUND_UP(offmap->map.value_size, 4) *
FIELD_SIZEOF(struct nfp_bpf_map, use_map[0]);
nfp_map = kzalloc(sizeof(*nfp_map) + use_map_size, GFP_USER);
if (!nfp_map)
return -ENOMEM;
offmap->dev_priv = nfp_map;
nfp_map->offmap = offmap;
nfp_map->bpf = bpf;
res = nfp_bpf_ctrl_alloc_map(bpf, &offmap->map);
if (res < 0) {
kfree(nfp_map);
return res;
}
nfp_map->tid = res;
offmap->dev_ops = &nfp_bpf_map_ops;
bpf->maps_in_use++;
bpf->map_elems_in_use += offmap->map.max_entries;
list_add_tail(&nfp_map->l, &bpf->map_list);
return 0;
}
static int
nfp_bpf_map_free(struct nfp_app_bpf *bpf, struct bpf_offloaded_map *offmap)
{
struct nfp_bpf_map *nfp_map = offmap->dev_priv;
nfp_bpf_ctrl_free_map(bpf, nfp_map);
list_del_init(&nfp_map->l);
bpf->map_elems_in_use -= offmap->map.max_entries;
bpf->maps_in_use--;
kfree(nfp_map);
return 0;
}
int nfp_ndo_bpf(struct nfp_app *app, struct nfp_net *nn, struct netdev_bpf *bpf)
{
switch (bpf->command) {
case BPF_OFFLOAD_MAP_ALLOC:
return nfp_bpf_map_alloc(app->priv, bpf->offmap);
case BPF_OFFLOAD_MAP_FREE:
return nfp_bpf_map_free(app->priv, bpf->offmap);
default:
return -EINVAL;
}
}
static unsigned long
nfp_bpf_perf_event_copy(void *dst, const void *src,
unsigned long off, unsigned long len)
{
memcpy(dst, src + off, len);
return 0;
}
int nfp_bpf_event_output(struct nfp_app_bpf *bpf, const void *data,
unsigned int len)
{
struct cmsg_bpf_event *cbe = (void *)data;
struct nfp_bpf_neutral_map *record;
u32 pkt_size, data_size, map_id;
u64 map_id_full;
if (len < sizeof(struct cmsg_bpf_event))
return -EINVAL;
pkt_size = be32_to_cpu(cbe->pkt_size);
data_size = be32_to_cpu(cbe->data_size);
map_id_full = be64_to_cpu(cbe->map_ptr);
map_id = map_id_full;
if (len < sizeof(struct cmsg_bpf_event) + pkt_size + data_size)
return -EINVAL;
if (cbe->hdr.ver != CMSG_MAP_ABI_VERSION)
return -EINVAL;
rcu_read_lock();
record = rhashtable_lookup_fast(&bpf->maps_neutral, &map_id,
nfp_bpf_maps_neutral_params);
if (!record || map_id_full > U32_MAX) {
rcu_read_unlock();
cmsg_warn(bpf, "perf event: map id %lld (0x%llx) not recognized, dropping event\n",
map_id_full, map_id_full);
return -EINVAL;
}
bpf_event_output(record->ptr, be32_to_cpu(cbe->cpu_id),
&cbe->data[round_up(pkt_size, 4)], data_size,
cbe->data, pkt_size, nfp_bpf_perf_event_copy);
rcu_read_unlock();
return 0;
}
static int
nfp_net_bpf_load(struct nfp_net *nn, struct bpf_prog *prog,
struct netlink_ext_ack *extack)
{
struct nfp_prog *nfp_prog = prog->aux->offload->dev_priv;
unsigned int fw_mtu, pkt_off, max_stack, max_prog_len;
dma_addr_t dma_addr;
void *img;
int err;
fw_mtu = nn_readb(nn, NFP_NET_CFG_BPF_INL_MTU) * 64 - 32;
pkt_off = min(prog->aux->max_pkt_offset, nn->dp.netdev->mtu);
if (fw_mtu < pkt_off) {
NL_SET_ERR_MSG_MOD(extack, "BPF offload not supported with potential packet access beyond HW packet split boundary");
return -EOPNOTSUPP;
}
max_stack = nn_readb(nn, NFP_NET_CFG_BPF_STACK_SZ) * 64;
if (nfp_prog->stack_size > max_stack) {
NL_SET_ERR_MSG_MOD(extack, "stack too large");
return -EOPNOTSUPP;
}
max_prog_len = nn_readw(nn, NFP_NET_CFG_BPF_MAX_LEN);
if (nfp_prog->prog_len > max_prog_len) {
NL_SET_ERR_MSG_MOD(extack, "program too long");
return -EOPNOTSUPP;
}
img = nfp_bpf_relo_for_vnic(nfp_prog, nn->app_priv);
if (IS_ERR(img))
return PTR_ERR(img);
dma_addr = dma_map_single(nn->dp.dev, img,
nfp_prog->prog_len * sizeof(u64),
DMA_TO_DEVICE);
if (dma_mapping_error(nn->dp.dev, dma_addr)) {
kfree(img);
return -ENOMEM;
}
nn_writew(nn, NFP_NET_CFG_BPF_SIZE, nfp_prog->prog_len);
nn_writeq(nn, NFP_NET_CFG_BPF_ADDR, dma_addr);
/* Load up the JITed code */
err = nfp_net_reconfig(nn, NFP_NET_CFG_UPDATE_BPF);
if (err)
NL_SET_ERR_MSG_MOD(extack,
"FW command error while loading BPF");
dma_unmap_single(nn->dp.dev, dma_addr, nfp_prog->prog_len * sizeof(u64),
DMA_TO_DEVICE);
kfree(img);
return err;
}
static void
nfp_net_bpf_start(struct nfp_net *nn, struct netlink_ext_ack *extack)
{
int err;
/* Enable passing packets through BPF function */
nn->dp.ctrl |= NFP_NET_CFG_CTRL_BPF;
nn_writel(nn, NFP_NET_CFG_CTRL, nn->dp.ctrl);
err = nfp_net_reconfig(nn, NFP_NET_CFG_UPDATE_GEN);
if (err)
NL_SET_ERR_MSG_MOD(extack,
"FW command error while enabling BPF");
}
static int nfp_net_bpf_stop(struct nfp_net *nn)
{
if (!(nn->dp.ctrl & NFP_NET_CFG_CTRL_BPF))
return 0;
nn->dp.ctrl &= ~NFP_NET_CFG_CTRL_BPF;
nn_writel(nn, NFP_NET_CFG_CTRL, nn->dp.ctrl);
return nfp_net_reconfig(nn, NFP_NET_CFG_UPDATE_GEN);
}
int nfp_net_bpf_offload(struct nfp_net *nn, struct bpf_prog *prog,
bool old_prog, struct netlink_ext_ack *extack)
{
int err;
if (prog && !bpf_offload_dev_match(prog, nn->dp.netdev))
return -EINVAL;
if (prog && old_prog) {
u8 cap;
cap = nn_readb(nn, NFP_NET_CFG_BPF_CAP);
if (!(cap & NFP_NET_BPF_CAP_RELO)) {
NL_SET_ERR_MSG_MOD(extack,
"FW does not support live reload");
return -EBUSY;
}
}
/* Something else is loaded, different program type? */
if (!old_prog && nn->dp.ctrl & NFP_NET_CFG_CTRL_BPF)
return -EBUSY;
if (old_prog && !prog)
return nfp_net_bpf_stop(nn);
err = nfp_net_bpf_load(nn, prog, extack);
if (err)
return err;
if (!old_prog)
nfp_net_bpf_start(nn, extack);
return 0;
}
const struct bpf_prog_offload_ops nfp_bpf_dev_ops = {
.insn_hook = nfp_verify_insn,
.finalize = nfp_bpf_finalize,
.replace_insn = nfp_bpf_opt_replace_insn,
.remove_insns = nfp_bpf_opt_remove_insns,
.prepare = nfp_bpf_verifier_prep,
.translate = nfp_bpf_translate,
.destroy = nfp_bpf_destroy,
};
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