net: Don't overwrite waiting packets with asynchronous replies

Peter originally sent a fix, but it breaks a number of other things.
This addresses the original reported issue in a different way.

That report was:

> U-Boot has 1 common buffer to send Ethernet frames, pointed to by
> net_tx_packet.  When sending to an IP address without knowing the MAC
> address, U-Boot makes an ARP request (using the arp_tx_packet buffer)
> to find out the MAC address of the IP addressr. When a matching ARP
> reply is received, U-Boot continues sending the frame stored in the
> net_tx_packet buffer.
>
> However, in the mean time, if U-Boot needs to send out any network
> packets (e.g. replying ping packets or ARP requests for its own IP
> address etc.), it will use the net_tx_packet buffer to prepare the
> new packet. Thus this buffer is no longer the original packet meant
> to be transmitted after the ARP reply. The original packet will be
> lost.

This instead uses the ARP tx buffer to send async replies in the case
where we are actively waiting for an ARP reply.

Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>

Reported-by: Tran Tien Dat <peter.trantiendat@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
This commit is contained in:
Joe Hershberger 2018-09-26 16:49:02 -05:00
parent 72ff004258
commit ac3f26cc15
6 changed files with 29 additions and 10 deletions

View File

@ -655,6 +655,14 @@ static inline void net_set_state(enum net_loop_state state)
net_state = state;
}
/*
* net_get_async_tx_pkt_buf - Get a packet buffer that is not in use for
* sending an asynchronous reply
*
* returns - ptr to packet buffer
*/
uchar * net_get_async_tx_pkt_buf(void);
/* Transmit a packet */
static inline void net_send_packet(uchar *pkt, int len)
{

View File

@ -34,8 +34,7 @@ uchar *arp_wait_packet_ethaddr;
int arp_wait_tx_packet_size;
ulong arp_wait_timer_start;
int arp_wait_try;
static uchar *arp_tx_packet; /* THE ARP transmit packet */
uchar *arp_tx_packet; /* THE ARP transmit packet */
static uchar arp_tx_packet_buf[PKTSIZE_ALIGN + PKTALIGN];
void arp_init(void)
@ -126,6 +125,7 @@ void arp_receive(struct ethernet_hdr *et, struct ip_udp_hdr *ip, int len)
struct arp_hdr *arp;
struct in_addr reply_ip_addr;
int eth_hdr_size;
uchar *tx_packet;
/*
* We have to deal with two types of ARP packets:
@ -182,8 +182,9 @@ void arp_receive(struct ethernet_hdr *et, struct ip_udp_hdr *ip, int len)
(net_read_ip(&arp->ar_spa).s_addr & net_netmask.s_addr))
udelay(5000);
#endif
memcpy(net_tx_packet, et, eth_hdr_size + ARP_HDR_SIZE);
net_send_packet(net_tx_packet, eth_hdr_size + ARP_HDR_SIZE);
tx_packet = net_get_async_tx_pkt_buf();
memcpy(tx_packet, et, eth_hdr_size + ARP_HDR_SIZE);
net_send_packet(tx_packet, eth_hdr_size + ARP_HDR_SIZE);
return;
case ARPOP_REPLY: /* arp reply */

View File

@ -20,6 +20,7 @@ extern uchar *arp_wait_packet_ethaddr;
extern int arp_wait_tx_packet_size;
extern ulong arp_wait_timer_start;
extern int arp_wait_try;
extern uchar *arp_tx_packet;
void arp_init(void);
void arp_request(void);

View File

@ -799,6 +799,14 @@ void net_set_timeout_handler(ulong iv, thand_f *f)
}
}
uchar *net_get_async_tx_pkt_buf(void)
{
if (arp_is_waiting())
return arp_tx_packet; /* If we are waiting, we already sent */
else
return net_tx_packet;
}
int net_send_udp_packet(uchar *ether, struct in_addr dest, int dport, int sport,
int payload_len)
{

View File

@ -84,6 +84,7 @@ void ping_receive(struct ethernet_hdr *et, struct ip_udp_hdr *ip, int len)
struct icmp_hdr *icmph = (struct icmp_hdr *)&ip->udp_src;
struct in_addr src_ip;
int eth_hdr_size;
uchar *tx_packet;
switch (icmph->type) {
case ICMP_ECHO_REPLY:
@ -107,8 +108,10 @@ void ping_receive(struct ethernet_hdr *et, struct ip_udp_hdr *ip, int len)
icmph->type = ICMP_ECHO_REPLY;
icmph->checksum = 0;
icmph->checksum = compute_ip_checksum(icmph, len - IP_HDR_SIZE);
memcpy(net_tx_packet, et, eth_hdr_size + len);
net_send_packet(net_tx_packet, eth_hdr_size + len);
tx_packet = net_get_async_tx_pkt_buf();
memcpy(tx_packet, et, eth_hdr_size + len);
net_send_packet(tx_packet, eth_hdr_size + len);
return;
/* default:
return;*/

View File

@ -332,10 +332,9 @@ static int dm_test_eth_async_arp_reply(struct unit_test_state *uts)
sandbox_eth_set_tx_handler(0, sb_with_async_arp_handler);
/* Used by all of the ut_assert macros in the tx_handler */
sandbox_eth_set_priv(0, uts);
sandbox_eth_skip_timeout();
env_set("ethact", "eth@10002000");
ut_assert(net_loop(PING) == -ETIMEDOUT);
ut_assertok(net_loop(PING));
ut_asserteq_str("eth@10002000", env_get("ethact"));
sandbox_eth_set_tx_handler(0, NULL);
@ -418,10 +417,9 @@ static int dm_test_eth_async_ping_reply(struct unit_test_state *uts)
sandbox_eth_set_tx_handler(0, sb_with_async_ping_handler);
/* Used by all of the ut_assert macros in the tx_handler */
sandbox_eth_set_priv(0, uts);
sandbox_eth_skip_timeout();
env_set("ethact", "eth@10002000");
ut_assert(net_loop(PING) == -ETIMEDOUT);
ut_assertok(net_loop(PING));
ut_asserteq_str("eth@10002000", env_get("ethact"));
sandbox_eth_set_tx_handler(0, NULL);