e1000: NetClientInfo.receive_iov implemented

This patch implements the NetClientInfo.receive_iov method for the
e1000 device emulation. In this way a network backend that uses
qemu_sendv_packet() can deliver the fragmented packet without
requiring an additional copy in the frontend/backend network code
(nc_sendv_compat() function).

The existing method NetClientInfo.receive has been reimplemented
using the new method.

Signed-off-by: Vincenzo Maffione <v.maffione@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Vincenzo Maffione 2013-09-12 10:47:37 +02:00 committed by Stefan Hajnoczi
parent a26405b350
commit 97410dde60

View file

@ -32,6 +32,7 @@
#include "hw/loader.h"
#include "sysemu/sysemu.h"
#include "sysemu/dma.h"
#include "qemu/iov.h"
#include "e1000_regs.h"
@ -64,6 +65,8 @@ static int debugflags = DBGBIT(TXERR) | DBGBIT(GENERAL);
/* this is the size past which hardware will drop packets when setting LPE=1 */
#define MAXIMUM_ETHERNET_LPE_SIZE 16384
#define MAXIMUM_ETHERNET_HDR_LEN (14+4)
/*
* HW models:
* E1000_DEV_ID_82540EM works with Windows and Linux
@ -899,7 +902,7 @@ static uint64_t rx_desc_base(E1000State *s)
}
static ssize_t
e1000_receive(NetClientState *nc, const uint8_t *buf, size_t size)
e1000_receive_iov(NetClientState *nc, const struct iovec *iov, int iovcnt)
{
E1000State *s = qemu_get_nic_opaque(nc);
PCIDevice *d = PCI_DEVICE(s);
@ -908,8 +911,12 @@ e1000_receive(NetClientState *nc, const uint8_t *buf, size_t size)
unsigned int n, rdt;
uint32_t rdh_start;
uint16_t vlan_special = 0;
uint8_t vlan_status = 0, vlan_offset = 0;
uint8_t vlan_status = 0;
uint8_t min_buf[MIN_BUF_SIZE];
struct iovec min_iov;
uint8_t *filter_buf = iov->iov_base;
size_t size = iov_size(iov, iovcnt);
size_t iov_ofs = 0;
size_t desc_offset;
size_t desc_size;
size_t total_size;
@ -924,10 +931,16 @@ e1000_receive(NetClientState *nc, const uint8_t *buf, size_t size)
/* Pad to minimum Ethernet frame length */
if (size < sizeof(min_buf)) {
memcpy(min_buf, buf, size);
iov_to_buf(iov, iovcnt, 0, min_buf, size);
memset(&min_buf[size], 0, sizeof(min_buf) - size);
buf = min_buf;
size = sizeof(min_buf);
min_iov.iov_base = filter_buf = min_buf;
min_iov.iov_len = size = sizeof(min_buf);
iovcnt = 1;
iov = &min_iov;
} else if (iov->iov_len < MAXIMUM_ETHERNET_HDR_LEN) {
/* This is very unlikely, but may happen. */
iov_to_buf(iov, iovcnt, 0, min_buf, MAXIMUM_ETHERNET_HDR_LEN);
filter_buf = min_buf;
}
/* Discard oversized packets if !LPE and !SBP. */
@ -938,14 +951,24 @@ e1000_receive(NetClientState *nc, const uint8_t *buf, size_t size)
return size;
}
if (!receive_filter(s, buf, size))
if (!receive_filter(s, filter_buf, size)) {
return size;
}
if (vlan_enabled(s) && is_vlan_packet(s, buf)) {
vlan_special = cpu_to_le16(be16_to_cpup((uint16_t *)(buf + 14)));
memmove((uint8_t *)buf + 4, buf, 12);
if (vlan_enabled(s) && is_vlan_packet(s, filter_buf)) {
vlan_special = cpu_to_le16(be16_to_cpup((uint16_t *)(filter_buf
+ 14)));
iov_ofs = 4;
if (filter_buf == iov->iov_base) {
memmove(filter_buf + 4, filter_buf, 12);
} else {
iov_from_buf(iov, iovcnt, 4, filter_buf, 12);
while (iov->iov_len <= iov_ofs) {
iov_ofs -= iov->iov_len;
iov++;
}
}
vlan_status = E1000_RXD_STAT_VP;
vlan_offset = 4;
size -= 4;
}
@ -967,12 +990,23 @@ e1000_receive(NetClientState *nc, const uint8_t *buf, size_t size)
desc.status |= (vlan_status | E1000_RXD_STAT_DD);
if (desc.buffer_addr) {
if (desc_offset < size) {
size_t iov_copy;
hwaddr ba = le64_to_cpu(desc.buffer_addr);
size_t copy_size = size - desc_offset;
if (copy_size > s->rxbuf_size) {
copy_size = s->rxbuf_size;
}
pci_dma_write(d, le64_to_cpu(desc.buffer_addr),
buf + desc_offset + vlan_offset, copy_size);
do {
iov_copy = MIN(copy_size, iov->iov_len - iov_ofs);
pci_dma_write(d, ba, iov->iov_base + iov_ofs, iov_copy);
copy_size -= iov_copy;
ba += iov_copy;
iov_ofs += iov_copy;
if (iov_ofs == iov->iov_len) {
iov++;
iov_ofs = 0;
}
} while (copy_size);
}
desc_offset += desc_size;
desc.length = cpu_to_le16(desc_size);
@ -1022,6 +1056,17 @@ e1000_receive(NetClientState *nc, const uint8_t *buf, size_t size)
return size;
}
static ssize_t
e1000_receive(NetClientState *nc, const uint8_t *buf, size_t size)
{
const struct iovec iov = {
.iov_base = (uint8_t *)buf,
.iov_len = size
};
return e1000_receive_iov(nc, &iov, 1);
}
static uint32_t
mac_readreg(E1000State *s, int index)
{
@ -1448,6 +1493,7 @@ static NetClientInfo net_e1000_info = {
.size = sizeof(NICState),
.can_receive = e1000_can_receive,
.receive = e1000_receive,
.receive_iov = e1000_receive_iov,
.cleanup = e1000_cleanup,
.link_status_changed = e1000_set_link_status,
};