[Qemu-devel] [PATCH 4/4] qemu:e1000: Add support for qemu_vlan_rxfilter

[Alex Williamson <alex.williamson@hp.com>]

Make use of qemu_vlan_rxfilter so that we can filter at a lower
level.  We implement callbacks for devices being added and removed
so that we can fall back to our own filtering or make another attempt
to push filtering off to someone else.

Signed-off-by: Alex Williamson <alex.williamson@hp.com>
---

Updated to address e1000 multicast hash table.

 hw/e1000.c |   81 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
 1 files changed, 79 insertions(+), 2 deletions(-)

diff --git a/hw/e1000.c b/hw/e1000.c
index 6f841d6..e3e5fa5 100644
--- a/hw/e1000.c
+++ b/hw/e1000.c
@@ -85,6 +85,7 @@ typedef struct E1000State_st {
     uint32_t rxbuf_size;
     uint32_t rxbuf_min_shift;
     int check_rxov;
+    int vlan_rxfilter;
     struct e1000_tx {
         unsigned char header[256];
         unsigned char vlan_header[4];
@@ -143,6 +144,66 @@ static const char phy_regcap[0x20] = {
     [PHY_ID2] = PHY_R,		[M88E1000_PHY_SPEC_STATUS] = PHY_R
 };
 
+static void e1000_set_vlan_rxfilter(E1000State *s)
+{
+    static const uint8_t bcast[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
+    uint32_t rctl = s->mac_reg[RCTL], ra[2], *rp;
+    uint8_t *buf;
+    int i, flags = 0;
+
+    /*
+     * If the guest has encoded anything in the multicast hash table,
+     * we're stuck doing the filtering ourselves.  This should only
+     * happen if the guest has already consumed the RAR table.
+     */
+    for (i = 0; i < 128; i++) {
+        if (s->mac_reg[MTA + i]) {
+            qemu_vlan_rxfilter(s->vc, QEMU_NET_PROMISC, 0, NULL);
+            s->vlan_rxfilter = 0;
+            return;
+        }
+    }
+
+    if (rctl & E1000_RCTL_UPE)
+        flags |= QEMU_NET_PROMISC;
+    if (rctl & E1000_RCTL_MPE)
+        flags |= QEMU_NET_ALLMULTI;
+
+    /* Allocate for maximum size, 16 + bcast */
+    buf = qemu_mallocz(17 * 6);
+
+    for (i = 0, rp = s->mac_reg + RA; rp < s->mac_reg + RA + 32; rp += 2) {
+        if (!(rp[1] & E1000_RAH_AV))
+            continue;
+        ra[0] = cpu_to_le32(rp[0]);
+        ra[1] = cpu_to_le32(rp[1]);
+        memcpy(&buf[i * 6], (uint8_t *)ra, 6);
+        i++;
+    }
+
+    if (rctl & E1000_RCTL_BAM) {
+        memcpy(&buf[i * 6], bcast, 6);
+        i++;
+    }
+
+    s->vlan_rxfilter = qemu_vlan_rxfilter(s->vc, flags, i, buf);
+    qemu_free(buf);
+}
+
+static void e1000_vlan_client_added(void *opaque)
+{
+    E1000State *s = opaque;
+
+    s->vlan_rxfilter = 0;
+}
+
+static void e1000_vlan_client_removed(void *opaque)
+{
+    E1000State *s = opaque;
+
+    e1000_set_vlan_rxfilter(s);
+}
+
 static void
 ioport_map(PCIDevice *pci_dev, int region_num, uint32_t addr,
            uint32_t size, int type)
@@ -198,6 +259,7 @@ set_rx_control(E1000State *s, int index, uint32_t val)
     s->rxbuf_min_shift = ((val / E1000_RCTL_RDMTS_QUAT) & 3) + 1;
     DBGOUT(RX, "RCTL: %d, mac_reg[RCTL] = 0x%x\n", s->mac_reg[RDT],
            s->mac_reg[RCTL]);
+    e1000_set_vlan_rxfilter(s);
 }
 
 static void
@@ -532,6 +594,9 @@ receive_filter(E1000State *s, const uint8_t *buf, int size)
             return 0;
     }
 
+    if (s->vlan_rxfilter)
+        return 1;
+
     if (rctl & E1000_RCTL_UPE)			// promiscuous
         return 1;
 
@@ -715,6 +780,13 @@ mac_writereg(E1000State *s, int index, uint32_t val)
 }
 
 static void
+mac_writereg_rx(E1000State *s, int index, uint32_t val)
+{
+    s->mac_reg[index] = val;
+    e1000_set_vlan_rxfilter(s);
+}
+
+static void
 set_rdt(E1000State *s, int index, uint32_t val)
 {
     s->check_rxov = 0;
@@ -790,8 +862,8 @@ static void (*macreg_writeops[])(E1000State *, int, uint32_t) = {
     [TDH] = set_16bit,	[RDH] = set_16bit,	[RDT] = set_rdt,
     [IMC] = set_imc,	[IMS] = set_ims,	[ICR] = set_icr,
     [EECD] = set_eecd,	[RCTL] = set_rx_control,
-    [RA ... RA+31] = &mac_writereg,
-    [MTA ... MTA+127] = &mac_writereg,
+    [RA ... RA+31] = &mac_writereg_rx,
+    [MTA ... MTA+127] = &mac_writereg_rx,
     [VFTA ... VFTA+127] = &mac_writereg,
 };
 enum { NWRITEOPS = ARRAY_SIZE(macreg_writeops) };
@@ -964,6 +1036,9 @@ nic_load(QEMUFile *f, void *opaque, int version_id)
         for (j = 0; j < mac_regarraystosave[i].size; j++)
             qemu_get_be32s(f,
                            s->mac_reg + mac_regarraystosave[i].array0 + j);
+
+    e1000_set_vlan_rxfilter(s);
+
     return 0;
 }
 
@@ -1088,6 +1163,8 @@ pci_e1000_init(PCIBus *bus, NICInfo *nd, int devfn)
     d->vc = qemu_new_vlan_client(nd->vlan, nd->model, nd->name,
                                  e1000_receive, e1000_can_receive, d);
     d->vc->link_status_changed = e1000_set_link_status;
+    d->vc->vlan_client_added = e1000_vlan_client_added;
+    d->vc->vlan_client_removed = e1000_vlan_client_removed;
 
     qemu_format_nic_info_str(d->vc, d->nd->macaddr);