rtl8139.c

xen虚拟机源代码安装包

        DEBUG_PRINT(("RTL8139: +++ transmit loopback mode\n"));
        rtl8139_do_receive(s, buf, size, do_interrupt);
    }
    else
    {
        qemu_send_packet(s->vc, buf, size);
    }
}

static int rtl8139_transmit_one(RTL8139State *s, int descriptor)
{
    if (!rtl8139_transmitter_enabled(s))
    {
        DEBUG_PRINT(("RTL8139: +++ cannot transmit from descriptor %d: transmitter disabled\n",
                     descriptor));
        s->TxStatus[descriptor] = TxAborted | TxHostOwns;
        return 0;
    }

    if (s->TxStatus[descriptor] & TxHostOwns)
    {
        DEBUG_PRINT(("RTL8139: +++ cannot transmit from descriptor %d: owned by host (%08x)\n",
                     descriptor, s->TxStatus[descriptor]));
        s->TxStatus[descriptor] = TxAborted | TxHostOwns;
        return 0;
    }

    DEBUG_PRINT(("RTL8139: +++ transmitting from descriptor %d\n", descriptor));

    int txsize = s->TxStatus[descriptor] & 0x1fff;
    uint8_t txbuffer[0x2000];

    DEBUG_PRINT(("RTL8139: +++ transmit reading %d bytes from host memory at 0x%08x\n",
                 txsize, s->TxAddr[descriptor]));

    cpu_physical_memory_read(s->TxAddr[descriptor], txbuffer, txsize);

    /* Mark descriptor as transferred */
    s->TxStatus[descriptor] |= TxHostOwns;
    s->TxStatus[descriptor] |= TxStatOK;

    rtl8139_transfer_frame(s, txbuffer, txsize, 0);

    DEBUG_PRINT(("RTL8139: +++ transmitted %d bytes from descriptor %d\n", txsize, descriptor));

    /* update interrupt */
    s->IntrStatus |= TxOK;
    rtl8139_update_irq(s);

    return 1;
}

/* structures and macros for task offloading */
typedef struct ip_header
{
    uint8_t  ip_ver_len;    /* version and header length */
    uint8_t  ip_tos;        /* type of service */
    uint16_t ip_len;        /* total length */
    uint16_t ip_id;         /* identification */
    uint16_t ip_off;        /* fragment offset field */
    uint8_t  ip_ttl;        /* time to live */
    uint8_t  ip_p;          /* protocol */
    uint16_t ip_sum;        /* checksum */
    uint32_t ip_src,ip_dst; /* source and dest address */
} ip_header;

#define IP_HEADER_VERSION_4 4
#define IP_HEADER_VERSION(ip) ((ip->ip_ver_len >> 4)&0xf)
#define IP_HEADER_LENGTH(ip) (((ip->ip_ver_len)&0xf) << 2)

typedef struct tcp_header
{
    uint16_t th_sport;		/* source port */
    uint16_t th_dport;		/* destination port */
    uint32_t th_seq;			/* sequence number */
    uint32_t th_ack;			/* acknowledgement number */
    uint16_t th_offset_flags; /* data offset, reserved 6 bits, TCP protocol flags */
    uint16_t th_win;			/* window */
    uint16_t th_sum;			/* checksum */
    uint16_t th_urp;			/* urgent pointer */
} tcp_header;

typedef struct udp_header
{
    uint16_t uh_sport; /* source port */
    uint16_t uh_dport; /* destination port */
    uint16_t uh_ulen;  /* udp length */
    uint16_t uh_sum;   /* udp checksum */
} udp_header;

typedef struct ip_pseudo_header
{
    uint32_t ip_src;
    uint32_t ip_dst;
    uint8_t  zeros;
    uint8_t  ip_proto;
    uint16_t ip_payload;
} ip_pseudo_header;

#define IP_PROTO_TCP 6
#define IP_PROTO_UDP 17

#define TCP_HEADER_DATA_OFFSET(tcp) (((be16_to_cpu(tcp->th_offset_flags) >> 12)&0xf) << 2)
#define TCP_FLAGS_ONLY(flags) ((flags)&0x3f)
#define TCP_HEADER_FLAGS(tcp) TCP_FLAGS_ONLY(be16_to_cpu(tcp->th_offset_flags))

#define TCP_HEADER_CLEAR_FLAGS(tcp, off) ((tcp)->th_offset_flags &= cpu_to_be16(~TCP_FLAGS_ONLY(off)))

#define TCP_FLAG_FIN  0x01
#define TCP_FLAG_PUSH 0x08

/* produces ones' complement sum of data */
static uint16_t ones_complement_sum(uint8_t *data, size_t len)
{
    uint32_t result = 0;

    for (; len > 1; data+=2, len-=2)
    {
        result += *(uint16_t*)data;
    }

    /* add the remainder byte */
    if (len)
    {
        uint8_t odd[2] = {*data, 0};
        result += *(uint16_t*)odd;
    }

    while (result>>16)
        result = (result & 0xffff) + (result >> 16);

    return result;
}

static uint16_t ip_checksum(void *data, size_t len)
{
    return ~ones_complement_sum((uint8_t*)data, len);
}

static int rtl8139_cplus_transmit_one(RTL8139State *s)
{
    if (!rtl8139_transmitter_enabled(s))
    {
        DEBUG_PRINT(("RTL8139: +++ C+ mode: transmitter disabled\n"));
        return 0;
    }

    if (!rtl8139_cp_transmitter_enabled(s))
    {
        DEBUG_PRINT(("RTL8139: +++ C+ mode: C+ transmitter disabled\n"));
        return 0 ;
    }

    int descriptor = s->currCPlusTxDesc;

    target_phys_addr_t cplus_tx_ring_desc =
        rtl8139_addr64(s->TxAddr[0], s->TxAddr[1]);

    /* Normal priority ring */
    cplus_tx_ring_desc += 16 * descriptor;

    DEBUG_PRINT(("RTL8139: +++ C+ mode reading TX descriptor %d from host memory at %08x0x%08x = 0x%8lx\n",
           descriptor, s->TxAddr[1], s->TxAddr[0], cplus_tx_ring_desc));

    uint32_t val, txdw0,txdw1,txbufLO,txbufHI;

    cpu_physical_memory_read(cplus_tx_ring_desc,    (uint8_t *)&val, 4);
    txdw0 = le32_to_cpu(val);
    cpu_physical_memory_read(cplus_tx_ring_desc+4,  (uint8_t *)&val, 4);
    txdw1 = le32_to_cpu(val);
    cpu_physical_memory_read(cplus_tx_ring_desc+8,  (uint8_t *)&val, 4);
    txbufLO = le32_to_cpu(val);
    cpu_physical_memory_read(cplus_tx_ring_desc+12, (uint8_t *)&val, 4);
    txbufHI = le32_to_cpu(val);

    DEBUG_PRINT(("RTL8139: +++ C+ mode TX descriptor %d %08x %08x %08x %08x\n",
           descriptor,
           txdw0, txdw1, txbufLO, txbufHI));

/* w0 ownership flag */
#define CP_TX_OWN (1<<31)
/* w0 end of ring flag */
#define CP_TX_EOR (1<<30)
/* first segment of received packet flag */
#define CP_TX_FS (1<<29)
/* last segment of received packet flag */
#define CP_TX_LS (1<<28)
/* large send packet flag */
#define CP_TX_LGSEN (1<<27)
/* large send MSS mask, bits 16...25 */
#define CP_TC_LGSEN_MSS_MASK ((1 << 12) - 1)

/* IP checksum offload flag */
#define CP_TX_IPCS (1<<18)
/* UDP checksum offload flag */
#define CP_TX_UDPCS (1<<17)
/* TCP checksum offload flag */
#define CP_TX_TCPCS (1<<16)

/* w0 bits 0...15 : buffer size */
#define CP_TX_BUFFER_SIZE (1<<16)
#define CP_TX_BUFFER_SIZE_MASK (CP_TX_BUFFER_SIZE - 1)
/* w1 tag available flag */
#define CP_RX_TAGC (1<<17)
/* w1 bits 0...15 : VLAN tag */
#define CP_TX_VLAN_TAG_MASK ((1<<16) - 1)
/* w2 low  32bit of Rx buffer ptr */
/* w3 high 32bit of Rx buffer ptr */

/* set after transmission */
/* FIFO underrun flag */
#define CP_TX_STATUS_UNF (1<<25)
/* transmit error summary flag, valid if set any of three below */
#define CP_TX_STATUS_TES (1<<23)
/* out-of-window collision flag */
#define CP_TX_STATUS_OWC (1<<22)
/* link failure flag */
#define CP_TX_STATUS_LNKF (1<<21)
/* excessive collisions flag */
#define CP_TX_STATUS_EXC (1<<20)

    if (!(txdw0 & CP_TX_OWN))
    {
        DEBUG_PRINT(("RTL8139: C+ Tx mode : descriptor %d is owned by host\n", descriptor));
        return 0 ;
    }

    DEBUG_PRINT(("RTL8139: +++ C+ Tx mode : transmitting from descriptor %d\n", descriptor));

    if (txdw0 & CP_TX_FS)
    {
        DEBUG_PRINT(("RTL8139: +++ C+ Tx mode : descriptor %d is first segment descriptor\n", descriptor));

        /* reset internal buffer offset */
        s->cplus_txbuffer_offset = 0;
    }

    int txsize = txdw0 & CP_TX_BUFFER_SIZE_MASK;
    target_phys_addr_t tx_addr = rtl8139_addr64(txbufLO, txbufHI);

    /* make sure we have enough space to assemble the packet */
    if (!s->cplus_txbuffer)
    {
        s->cplus_txbuffer_len = CP_TX_BUFFER_SIZE;
        s->cplus_txbuffer = malloc(s->cplus_txbuffer_len);
        s->cplus_txbuffer_offset = 0;

        DEBUG_PRINT(("RTL8139: +++ C+ mode transmission buffer allocated space %d\n", s->cplus_txbuffer_len));
    }

    if (s->cplus_txbuffer && s->cplus_txbuffer_offset + txsize >= s->cplus_txbuffer_len)
    {
	free(s->cplus_txbuffer);
	s->cplus_txbuffer = NULL;

	DEBUG_PRINT(("RTL8139: +++ C+ mode transmission buffer space exceeded: %d\n", s->cplus_txbuffer_offset + txsize));
    }

    if (!s->cplus_txbuffer)
    {
        /* out of memory */

        DEBUG_PRINT(("RTL8139: +++ C+ mode transmiter failed to reallocate %d bytes\n", s->cplus_txbuffer_len));

        /* update tally counter */
        ++s->tally_counters.TxERR;
        ++s->tally_counters.TxAbt;

        return 0;
    }

    /* append more data to the packet */

    DEBUG_PRINT(("RTL8139: +++ C+ mode transmit reading %d bytes from host memory at %016" PRIx64 " to offset %d\n",
                 txsize, (uint64_t)tx_addr, s->cplus_txbuffer_offset));

    cpu_physical_memory_read(tx_addr, s->cplus_txbuffer + s->cplus_txbuffer_offset, txsize);
    s->cplus_txbuffer_offset += txsize;

    /* seek to next Rx descriptor */
    if (txdw0 & CP_TX_EOR)
    {
        s->currCPlusTxDesc = 0;
    }
    else
    {
        ++s->currCPlusTxDesc;
        if (s->currCPlusTxDesc >= 64)
            s->currCPlusTxDesc = 0;
    }

    /* transfer ownership to target */
    txdw0 &= ~CP_RX_OWN;

    /* reset error indicator bits */
    txdw0 &= ~CP_TX_STATUS_UNF;
    txdw0 &= ~CP_TX_STATUS_TES;
    txdw0 &= ~CP_TX_STATUS_OWC;
    txdw0 &= ~CP_TX_STATUS_LNKF;
    txdw0 &= ~CP_TX_STATUS_EXC;

    /* update ring data */
    val = cpu_to_le32(txdw0);
    cpu_physical_memory_write(cplus_tx_ring_desc,    (uint8_t *)&val, 4);
//    val = cpu_to_le32(txdw1);
//    cpu_physical_memory_write(cplus_tx_ring_desc+4,  &val, 4);

    /* Now decide if descriptor being processed is holding the last segment of packet */
    if (txdw0 & CP_TX_LS)
    {
        DEBUG_PRINT(("RTL8139: +++ C+ Tx mode : descriptor %d is last segment descriptor\n", descriptor));

        /* can transfer fully assembled packet */

        uint8_t *saved_buffer  = s->cplus_txbuffer;
        int      saved_size    = s->cplus_txbuffer_offset;
        int      saved_buffer_len = s->cplus_txbuffer_len;

        /* reset the card space to protect from recursive call */
        s->cplus_txbuffer = NULL;
        s->cplus_txbuffer_offset = 0;
        s->cplus_txbuffer_len = 0;

        if (txdw0 & (CP_TX_IPCS | CP_TX_UDPCS | CP_TX_TCPCS | CP_TX_LGSEN))
        {
            DEBUG_PRINT(("RTL8139: +++ C+ mode offloaded task checksum\n"));

            #define ETH_P_IP	0x0800		/* Internet Protocol packet	*/
            #define ETH_HLEN    14
            #define ETH_MTU     1500

            /* ip packet header */
            ip_header *ip = 0;
            int hlen = 0;
            uint8_t  ip_protocol = 0;
            uint16_t ip_data_len = 0;

            uint8_t *eth_payload_data = 0;
            size_t   eth_payload_len  = 0;

            int proto = be16_to_cpu(*(uint16_t *)(saved_buffer + 12));
            if (proto == ETH_P_IP)
            {
                DEBUG_PRINT(("RTL8139: +++ C+ mode has IP packet\n"));

                /* not aligned */
                eth_payload_data = saved_buffer + ETH_HLEN;
                eth_payload_len  = saved_size   - ETH_HLEN;

                ip = (ip_header*)eth_payload_data;

                if (IP_HEADER_VERSION(ip) != IP_HEADER_VERSION_4) {
                    DEBUG_PRINT(("RTL8139: +++ C+ mode packet has bad IP version %d expected %d\n", IP_HEADER_VERSION(ip), IP_HEADER_VERSION_4));
                    ip = NULL;
                } else {
                    hlen = IP_HEADER_LENGTH(ip);
                    ip_protocol = ip->ip_p;
                    ip_data_len = be16_to_cpu(ip->ip_len) - hlen;
                }
            }

            if (ip)
            {
                if (txdw0 & CP_TX_IPCS)
                {
                    DEBUG_PRINT(("RTL8139: +++ C+ mode need IP checksum\n"));

                    if (hlen<sizeof(ip_header) || hlen>eth_payload_len) {/* min header length */
                        /* bad packet header len */
                        /* or packet too short */
                    }
                    else
                    {
                        ip->ip_sum = 0;
                        ip->ip_sum = ip_checksum(ip, hlen);
                        DEBUG_PRINT(("RTL8139: +++ C+ mode IP header len=%d checksum=%04x\n", hlen, ip->ip_sum));
                    }
                }

                if ((txdw0 & CP_TX_LGSEN) && ip_protocol == IP_PROTO_TCP)
                {
#if defined (DEBUG_RTL8139)
                    int large_send_mss = (txdw0 >> 16) & CP_TC_LGSEN_MSS_MASK;
#endif
                    DEBUG_PRINT(("RTL8139: +++ C+ mode offloaded task TSO MTU=%d IP data %d frame data %d specified MSS=%d\n",
                                 ETH_MTU, ip_data_len, saved_size - ETH_HLEN, large_send_mss));

                    int tcp_send_offset = 0;
                    int send_count = 0;

                    /* maximum IP header length is 60 bytes */
                    uint8_t saved_ip_header[60];

                    /* save IP header template; data area is used in tcp checksum calculation */
                    memcpy(saved_ip_header, eth_payload_data, hlen);

                    /* a placeholder for checksum calculation routine in tcp case */
                    uint8_t *data_to_checksum     = eth_payload_data + hlen - 12;
                    //                    size_t   data_to_checksum_len = eth_payload_len  - hlen + 12;

                    /* pointer to TCP header */
                    tcp_header *p_tcp_hdr = (tcp_header*)(eth_payload_data + hlen);

                    int tcp_hlen = TCP_HEADER_DATA_OFFSET(p_tcp_hdr);

                    /* ETH_MTU = ip header len + tcp header len + payload */
                    int tcp_data_len = ip_data_len - tcp_hlen;
                    int tcp_chunk_size = ETH_MTU - hlen - tcp_hlen;

                    DEBUG_PRINT(("RTL8139: +++ C+ mode TSO IP data len %d TCP hlen %d TCP data len %d TCP chunk size %d\n",
                                 ip_data_len, tcp_hlen, tcp_data_len, tcp_chunk_size));

                    /* note the cycle below overwrites IP header data,
                       but restores it from saved_ip_header before sending packet */

                    int is_last_frame = 0;

                    for (tcp_send_offset = 0; tcp_send_offset < tcp_data_len; tcp_send_offset += tcp_chunk_size)
                    {
                        uint16_t chunk_size = tcp_chunk_size;

                        /* check if this is the last frame */
                        if (tcp_send_offset + tcp_chunk_size >= tcp_data_len)
                        {
                            is_last_frame = 1;
                            chunk_size = tcp_data_len - tcp_send_offset;
                        }

                        DEBUG_PRINT(("RTL8139: +++ C+ mode TSO TCP seqno %08x\n", be32_to_cpu(p_tcp_hdr->th_seq)));

                        /* add 4 TCP pseudoheader fields */
                        /* copy IP source and destination fields */
                        memcpy(data_to_checksum, saved_ip_header + 12, 8);

                        DEBUG_PRINT(("RTL8139: +++ C+ mode TSO calculating TCP checksum for packet with %d bytes data\n", tcp_hlen + chunk_size));

                        if (tcp_send_offset)
                        {