OpenE2K/qemu-e2k
13
4
Fork 0
Code Issues 4 Pull Requests Projects 2 Releases Activity

eepro100: Pad received short frames

Browse Source 
QEMU sends frames smaller than 60 bytes to ethernet nics.
Such frames are rejected by real NICs and their emulations.
To avoid this behaviour, other NIC emulations pad received
frames. This patch enables this workaround for eepro100, too.

All related code is marked with CONFIG_PAD_RECEIVED_FRAMES,
so we can drop this in case QEMU's networking code is
ever changed.

Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
Stefan Weil 2011-04-30 22:40:07 +02:00 committed by Michael S. Tsirkin
parent 27112f18f9
commit 792f1d6394
1 changed files with 25 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

26
hw/eepro100.c
View File

@ -48,6 +48,15 @@
#include "eeprom93xx.h"
#include "sysemu.h"
/* QEMU sends frames smaller than 60 bytes to ethernet nics.
* Such frames are rejected by real nics and their emulations.
* To avoid this behaviour, other nic emulations pad received
* frames. The following definition enables this padding for
* eepro100, too. We keep the define around in case it might
* become useful the future if the core networking is ever
* changed to pad short packets itself. */
#define CONFIG_PAD_RECEIVED_FRAMES
#define KiB 1024
/* Debug EEPRO100 card. */
@ -1640,19 +1649,32 @@ static ssize_t nic_receive(VLANClientState *nc, const uint8_t * buf, size_t size
*/
EEPRO100State *s = DO_UPCAST(NICState, nc, nc)->opaque;
uint16_t rfd_status = 0xa000;
#if defined(CONFIG_PAD_RECEIVED_FRAMES)
uint8_t min_buf[60];
#endif
static const uint8_t broadcast_macaddr[6] =
{ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
#if defined(CONFIG_PAD_RECEIVED_FRAMES)
/* Pad to minimum Ethernet frame length */
if (size < sizeof(min_buf)) {
memcpy(min_buf, buf, size);
memset(&min_buf[size], 0, sizeof(min_buf) - size);
buf = min_buf;
size = sizeof(min_buf);
}
#endif
if (s->configuration[8] & 0x80) {
/* CSMA is disabled. */
logout("%p received while CSMA is disabled\n", s);
return -1;
#if !defined(CONFIG_PAD_RECEIVED_FRAMES)
} else if (size < 64 && (s->configuration[7] & BIT(0))) {
/* Short frame and configuration byte 7/0 (discard short receive) set:
* Short frame is discarded */
logout("%p received short frame (%zu byte)\n", s, size);
s->statistics.rx_short_frame_errors++;
#if 0
return -1;
#endif
} else if ((size > MAX_ETH_FRAME_SIZE + 4) && !(s->configuration[18] & BIT(3))) {
@ -1731,9 +1753,11 @@ static ssize_t nic_receive(VLANClientState *nc, const uint8_t * buf, size_t size
"(%zu bytes); data truncated\n", rfd_size, size);
size = rfd_size;
}
#if !defined(CONFIG_PAD_RECEIVED_FRAMES)
if (size < 64) {
rfd_status |= 0x0080;
}
#endif
TRACE(OTHER, logout("command 0x%04x, link 0x%08x, addr 0x%08x, size %u\n",
rfd_command, rx.link, rx.rx_buf_addr, rfd_size));
stw_phys(s->ru_base + s->ru_offset + offsetof(eepro100_rx_t, status),