/*
* Copyright (C) 2016 Netronome Systems, Inc.
*
* This software is dual licensed under the GNU General License Version 2,
* June 1991 as shown in the file COPYING in the top-level directory of this
* source tree or the BSD 2-Clause License provided below. You have the
* option to license this software under the complete terms of either license.
*
* The BSD 2-Clause License:
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* 1. Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer.
*
* 2. Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
/*
* nfp_net_offload.c
* Netronome network device driver: TC offload functions for PF and VF
*/
#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 <net/pkt_cls.h>
#include <net/tc_act/tc_gact.h>
#include <net/tc_act/tc_mirred.h>
#include "main.h"
#include "../nfp_net_ctrl.h"
#include "../nfp_net.h"
static int
nfp_net_bpf_offload_prepare(struct nfp_net *nn,
struct tc_cls_bpf_offload *cls_bpf,
struct nfp_bpf_result *res,
void **code, dma_addr_t *dma_addr, u16 max_instr)
{
unsigned int code_sz = max_instr * sizeof(u64);
unsigned int stack_size;
u16 start_off, done_off;
unsigned int max_mtu;
int ret;
max_mtu = nn_readb(nn, NFP_NET_CFG_BPF_INL_MTU) * 64 - 32;
if (max_mtu < nn->dp.netdev->mtu) {
nn_info(nn, "BPF offload not supported with MTU larger than HW packet split boundary\n");
return -EOPNOTSUPP;
}
start_off = nn_readw(nn, NFP_NET_CFG_BPF_START);
done_off = nn_readw(nn, NFP_NET_CFG_BPF_DONE);
stack_size = nn_readb(nn, NFP_NET_CFG_BPF_STACK_SZ) * 64;
if (cls_bpf->prog->aux->stack_depth > stack_size) {
nn_info(nn, "stack too large: program %dB > FW stack %dB\n",
cls_bpf->prog->aux->stack_depth, stack_size);
return -EOPNOTSUPP;
}
*code = dma_zalloc_coherent(nn->dp.dev, code_sz, dma_addr, GFP_KERNEL);
if (!*code)
return -ENOMEM;
ret = nfp_bpf_jit(cls_bpf->prog, *code, start_off, done_off,
max_instr, res);
if (ret)
goto out;
return 0;
out:
dma_free_coherent(nn->dp.dev, code_sz, *code, *dma_addr);
return ret;
}
static void
nfp_net_bpf_load_and_start(struct nfp_net *nn, u32 tc_flags,
void *code, dma_addr_t dma_addr,
unsigned int code_sz, unsigned int n_instr)
{
int err;
nn->dp.bpf_offload_skip_sw = !!(tc_flags & TCA_CLS_FLAGS_SKIP_SW);
nn_writew(nn, NFP_NET_CFG_BPF_SIZE, n_instr);
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)
nn_err(nn, "FW command error while loading BPF: %d\n", 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)
nn_err(nn, "FW command error while enabling BPF: %d\n", err);
dma_free_coherent(nn->dp.dev, code_sz, code, dma_addr);
}
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);
nn->dp.bpf_offload_skip_sw = 0;
return nfp_net_reconfig(nn, NFP_NET_CFG_UPDATE_GEN);
}
int nfp_net_bpf_offload(struct nfp_net *nn, struct tc_cls_bpf_offload *cls_bpf)
{
struct nfp_bpf_result res;
dma_addr_t dma_addr;
u16 max_instr;
void *code;
int err;
max_instr = nn_readw(nn, NFP_NET_CFG_BPF_MAX_LEN);
switch (cls_bpf->command) {
case TC_CLSBPF_REPLACE:
/* There is nothing stopping us from implementing seamless
* replace but the simple method of loading I adopted in
* the firmware does not handle atomic replace (i.e. we have to
* stop the BPF offload and re-enable it). Leaking-in a few
* frames which didn't have BPF applied in the hardware should
* be fine if software fallback is available, though.
*/
if (nn->dp.bpf_offload_skip_sw)
return -EBUSY;
err = nfp_net_bpf_offload_prepare(nn, cls_bpf, &res, &code,
&dma_addr, max_instr);
if (err)
return err;
nfp_net_bpf_stop(nn);
nfp_net_bpf_load_and_start(nn, cls_bpf->gen_flags, code,
dma_addr, max_instr * sizeof(u64),
res.n_instr);
return 0;
case TC_CLSBPF_ADD:
if (nn->dp.ctrl & NFP_NET_CFG_CTRL_BPF)
return -EBUSY;
err = nfp_net_bpf_offload_prepare(nn, cls_bpf, &res, &code,
&dma_addr, max_instr);
if (err)
return err;
nfp_net_bpf_load_and_start(nn, cls_bpf->gen_flags, code,
dma_addr, max_instr * sizeof(u64),
res.n_instr);
return 0;
case TC_CLSBPF_DESTROY:
return nfp_net_bpf_stop(nn);
default:
return -EOPNOTSUPP;
}
}
