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/* -*- c++ -*- */
/*
* Copyright 2008,2009 Free Software Foundation, Inc.
*
* This file is part of GNU Radio
*
* GNU Radio is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3, or (at your option)
* any later version.
*
* GNU Radio is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include "eth_buffer.h"
#include "ethernet.h"
#include <usrp2/data_handler.h>
#include <linux/if_packet.h>
#include <sys/socket.h>
#include <sys/mman.h>
#include <sys/poll.h>
#include <iostream>
#include <cmath>
#include <errno.h>
#include <stdexcept>
#include <string.h>
#include <cstdio>
#define ETH_BUFFER_DEBUG 0 // define to 0 or 1
#if ETH_BUFFER_DEBUG
#define DEBUG_LOG(x) ::write(2, (x), 1)
#else
#define DEBUG_LOG(X)
#endif
#define DEFAULT_MEM_SIZE 25e6 // ~0.25s @ 100 MB/s
#define MAX_MEM_SIZE 1000e6 // ~10.00s @ 100 MB/s.
#define MAX_SLAB_SIZE 131072 // 128 KB (FIXME fish out of /proc/slabinfo)
#define MAX_PKT_SIZE 1512 // we don't do jumbo frames
namespace usrp2 {
eth_buffer::eth_buffer(size_t rx_bufsize)
: d_fd(0), d_using_tpring(false), d_buflen(0), d_buf(0), d_frame_nr(0),
d_frame_size(0), d_head(0), d_ring(0), d_ethernet(new ethernet())
{
if (rx_bufsize == 0)
d_buflen = (size_t)DEFAULT_MEM_SIZE;
else
d_buflen = std::min((size_t)MAX_MEM_SIZE, rx_bufsize);
memset(d_mac, 0, sizeof(d_mac));
}
eth_buffer::~eth_buffer()
{
close();
}
bool
eth_buffer::open(const std::string &ifname, int protocol)
{
if (!d_ethernet->open(ifname, protocol)) {
std::cerr << "eth_buffer: unable to open interface "
<< ifname << std::endl;
return false;
}
d_fd = d_ethernet->fd();
memcpy(d_mac, d_ethernet->mac(), sizeof(d_mac));
struct tpacket_req req;
size_t page_size = getpagesize();
// Calculate minimum power-of-two aligned size for frames
req.tp_frame_size =
(unsigned int)rint(pow(2, ceil(log2(TPACKET_ALIGN(TPACKET_HDRLEN)+TPACKET_ALIGN(MAX_PKT_SIZE)))));
d_frame_size = req.tp_frame_size;
// Calculate minimum contiguous pages needed to enclose a frame
int npages = (page_size > req.tp_frame_size) ? 1 : ((req.tp_frame_size+page_size-1)/page_size);
req.tp_block_size = page_size << (int)ceil(log2(npages));
// Calculate number of blocks
req.tp_block_nr = (int)(d_buflen/req.tp_block_size);
// Recalculate buffer length
d_buflen = req.tp_block_nr*req.tp_block_size;
// Finally, calculate total number of frames. Since frames, blocks,
// and pages are all power-of-two aligned, frames are contiguous
req.tp_frame_nr = d_buflen/req.tp_frame_size;
d_frame_nr = req.tp_frame_nr;
#if 0
if (ETH_BUFFER_DEBUG)
std::cerr << "eth_buffer:"
<< " frame_size=" << req.tp_frame_size
<< " block_size=" << req.tp_block_size
<< " block_nr=" << req.tp_block_nr
<< " frame_nr=" << req.tp_frame_nr
<< " buflen=" << d_buflen
<< std::endl;
#endif
// Try to get kernel shared memory buffer
if (setsockopt(d_fd, SOL_PACKET, PACKET_RX_RING, (void *)&req, sizeof(req))) {
perror("eth_buffer: setsockopt");
d_using_tpring = false;
if (!(d_buf = (uint8_t *)malloc(d_buflen))) {
std::cerr << "eth_buffer: failed to allocate packet memory" << std::endl;
return false;
}
std::cerr << "eth_buffer: using malloc'd memory for buffer" << std::endl;
}
else {
d_using_tpring = true;
void *p = mmap(0, d_buflen, PROT_READ|PROT_WRITE, MAP_SHARED, d_fd, 0);
if (p == MAP_FAILED){
perror("eth_buffer: mmap");
return false;
}
d_buf = (uint8_t *) p;
if (ETH_BUFFER_DEBUG)
std::cerr << "eth_buffer: using kernel shared mem for buffer" << std::endl;
}
// Initialize our pointers into the packet ring
d_ring = std::vector<uint8_t *>(req.tp_frame_nr);
for (unsigned int i=0; i < req.tp_frame_nr; i++) {
d_ring[i] = (uint8_t *)(d_buf+i*req.tp_frame_size);
}
// If not using kernel ring, instantiate select/read thread here
return true;
}
bool
eth_buffer::close()
{
// if we have background thread, stop it here
if(d_buf) {
if (!d_using_tpring)
free(d_buf);
else
munmap(d_buf, d_buflen);
}
return d_ethernet->close();
}
bool
eth_buffer::attach_pktfilter(pktfilter *pf)
{
return d_ethernet->attach_pktfilter(pf);
}
inline bool
eth_buffer::frame_available()
{
return (((tpacket_hdr *)d_ring[d_head])->tp_status != TP_STATUS_KERNEL);
}
eth_buffer::result
eth_buffer::rx_frames(data_handler *f, int timeout_in_ms)
{
DEBUG_LOG("\n");
while (!frame_available()) {
if (timeout_in_ms == 0) {
DEBUG_LOG("w");
return EB_WOULD_BLOCK;
}
struct pollfd pfd;
pfd.fd = d_fd;
pfd.revents = 0;
pfd.events = POLLIN;
DEBUG_LOG("P");
int pres = poll(&pfd, 1, timeout_in_ms);
if (pres == -1) {
perror("poll");
return EB_ERROR;
}
if (pres == 0) {
DEBUG_LOG("t");
return EB_TIMED_OUT;
}
}
// Iterate through available packets
while (frame_available()) {
// Get start of ethernet frame and length
tpacket_hdr *hdr = (tpacket_hdr *)d_ring[d_head];
void *base = (uint8_t *)hdr+hdr->tp_mac;
size_t len = hdr->tp_len;
// FYI, (base % 4 == 2) Not what we want given the current FPGA
// code. This means that our uint32_t samples are not 4-byte
// aligned. We'll have to deal with it downstream.
if (0)
fprintf(stderr, "eth_buffer: base = %p tp_mac = %3d tp_net = %3d\n",
base, hdr->tp_mac, hdr->tp_net);
// Invoke data handler
data_handler::result r = (*f)(base, len);
if (!(r & data_handler::KEEP))
hdr->tp_status = TP_STATUS_KERNEL; // mark it free
inc_head();
if (r & data_handler::DONE)
break;
}
DEBUG_LOG("|");
return EB_OK;
}
eth_buffer::result
eth_buffer::tx_frame(const void *base, size_t len, int flags)
{
DEBUG_LOG("T");
if (flags & EF_DONTWAIT) // FIXME: implement flags
throw std::runtime_error("tx_frame: EF_DONTWAIT not implemented");
int res = d_ethernet->write_packet(base, len);
if (res < 0 || (unsigned int)res != len)
return EB_ERROR;
return EB_OK;
}
eth_buffer::result
eth_buffer::tx_framev(const eth_iovec *iov, int iovcnt, int flags)
{
DEBUG_LOG("T");
if (flags & EF_DONTWAIT) // FIXME: implement flags
throw std::runtime_error("tx_frame: EF_DONTWAIT not implemented");
int res = d_ethernet->write_packetv(iov, iovcnt);
if (res < 0)
return EB_ERROR;
return EB_OK;
}
void
eth_buffer::release_frame(void *base)
{
// Get d_frame_size aligned header
tpacket_hdr *hdr = (tpacket_hdr *)((intptr_t)base & ~(d_frame_size-1));
hdr->tp_status = TP_STATUS_KERNEL; // mark it free
}
} // namespace usrp2
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