On Thu, Feb 03, 2011 at 09:36:57AM -0700, Alex Williamson wrote:
> On Thu, 2011-02-03 at 17:38 +0200, Michael S. Tsirkin wrote:
> > e1000 supports multi-buffer packets larger than rxbuf_size.
> >
> > This fixes the following (on linux):
> > - in guest: ifconfig eth1 mtu 16110
> > - in host: ifconfig tap0 mtu 16110
> > ping -s 16082 <guest-ip>
> >
> > Red Hat bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=602205
> >
> > Signed-off-by: Michael S. Tsirkin <m...@redhat.com>
> > ---
> > hw/e1000.c | 25 ++++++++++++++++++++-----
> > 1 files changed, 20 insertions(+), 5 deletions(-)
> >
> > diff --git a/hw/e1000.c b/hw/e1000.c
> > index af101bd..2c133ab 100644
> > --- a/hw/e1000.c
> > +++ b/hw/e1000.c
> > @@ -642,6 +642,8 @@ e1000_receive(VLANClientState *nc, const uint8_t *buf,
> > size_t size)
> > uint16_t vlan_special = 0;
> > uint8_t vlan_status = 0, vlan_offset = 0;
> > uint8_t min_buf[MIN_BUF_SIZE];
> > + size_t desc_offset;
> > + size_t desc_size;
> >
> > if (!(s->mac_reg[RCTL] & E1000_RCTL_EN))
> > return -1;
> > @@ -654,7 +656,7 @@ e1000_receive(VLANClientState *nc, const uint8_t *buf,
> > size_t size)
> > size = sizeof(min_buf);
> > }
> >
> > - if (size > s->rxbuf_size) {
> > + if (0 && size > s->rxbuf_size) {
> > DBGOUT(RX, "packet too large for buffers (%lu > %d)\n",
> > (unsigned long)size, s->rxbuf_size);
> > return -1;
>
> Why are we saving this code if it's unreachable?
Just a leftover.
> > @@ -672,8 +674,15 @@ e1000_receive(VLANClientState *nc, const uint8_t *buf,
> > size_t size)
> > }
> >
> > rdh_start = s->mac_reg[RDH];
> > + desc_offset = 0;
> > do {
> > + desc_size = size - desc_offset;
> > + if (desc_size > s->rxbuf_size) {
> > + desc_size = s->rxbuf_size;
> > + }
> > if (s->mac_reg[RDH] == s->mac_reg[RDT] && s->check_rxov) {
> > + /* Discard all data written so far */
> > + s->mac_reg[RDH] = rdh_start;
> > set_ics(s, 0, E1000_ICS_RXO);
> > return -1;
> > }
> > @@ -684,9 +693,15 @@ e1000_receive(VLANClientState *nc, const uint8_t *buf,
> > size_t size)
> > desc.status |= (vlan_status | E1000_RXD_STAT_DD);
> > if (desc.buffer_addr) {
> > cpu_physical_memory_write(le64_to_cpu(desc.buffer_addr),
> > - (void *)(buf + vlan_offset), size);
> > - desc.length = cpu_to_le16(size + fcs_len(s));
> > - desc.status |= E1000_RXD_STAT_EOP|E1000_RXD_STAT_IXSM;
> > + (void *)(buf + desc_offset +
> > vlan_offset),
> > + desc_size);
> > + desc_offset += desc_size;
> > + if (desc_offset >= size) {
> > + desc.length = cpu_to_le16(desc_size + fcs_len(s));
> > + desc.status |= E1000_RXD_STAT_EOP | E1000_RXD_STAT_IXSM;
> > + } else {
> > + desc.length = cpu_to_le16(desc_size);
> > + }
> > } else { // as per intel docs; skip descriptors with null buf addr
> > DBGOUT(RX, "Null RX descriptor!!\n");
> > }
> > @@ -702,7 +717,7 @@ e1000_receive(VLANClientState *nc, const uint8_t *buf,
> > size_t size)
> > set_ics(s, 0, E1000_ICS_RXO);
> > return -1;
> > }
> > - } while (desc.buffer_addr == 0);
> > + } while (desc_offset < size);
> >
> > s->mac_reg[GPRC]++;
> > s->mac_reg[TPR]++;
>
>
