Commit 97410dde authored by Vincenzo Maffione's avatar Vincenzo Maffione Committed by Stefan Hajnoczi
Browse files

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: default avatarVincenzo Maffione <v.maffione@gmail.com>
Signed-off-by: default avatarStefan Hajnoczi <stefanha@redhat.com>
parent a26405b3

hw/net/e1000.c

+58 −12
Original line number Diff line number Diff line
@@ -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,

};