--- /dev/null
+/* -*- 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_using_tpring && d_buf)
+ free(d_buf);
+
+ 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