qemu:virtio-net: Add additional MACs via a filter table (Alex Williamson)

Create a filter table and allow the guest to populate it with the
MAC class control commands.  We manage the size and usage of the
filter table including enabling promiscuous and all-multi modes
as necessary.  The guest should therefore assume the table is
infinite.  Eventually this might allow us to bind directly to a
hardware NIC and manipulate a physical MAC filter.

The specifics of the TABLE_SET command are documented in
virtio-net.h.  Separate buffers in the same command are used
for unicaste and multicast addresses for priority and
sychronization.  With this we can export the VIRTIO_NET_F_CTRL_RX
feature bit.

Signed-off-by: Alex Williamson <alex.williamson@hp.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>


git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6539 c046a42c-6fe2-441c-8c8c-71466251a162
This commit is contained in:
aliguori 2009-02-05 22:36:28 +00:00
parent 3831ab2094
commit b6503ed9b8
2 changed files with 109 additions and 2 deletions

View File

@ -16,7 +16,9 @@
#include "qemu-timer.h"
#include "virtio-net.h"
#define VIRTIO_NET_VM_VERSION 4
#define VIRTIO_NET_VM_VERSION 5
#define MAC_TABLE_ENTRIES 32
typedef struct VirtIONet
{
@ -32,6 +34,10 @@ typedef struct VirtIONet
int mergeable_rx_bufs;
int promisc;
int allmulti;
struct {
int in_use;
uint8_t *macs;
} mac_table;
} VirtIONet;
/* TODO
@ -87,13 +93,18 @@ static void virtio_net_reset(VirtIODevice *vdev)
/* Reset back to compatibility mode */
n->promisc = 1;
n->allmulti = 0;
/* Flush any MAC filter table state */
n->mac_table.in_use = 0;
memset(n->mac_table.macs, 0, MAC_TABLE_ENTRIES * ETH_ALEN);
}
static uint32_t virtio_net_get_features(VirtIODevice *vdev)
{
uint32_t features = (1 << VIRTIO_NET_F_MAC) |
(1 << VIRTIO_NET_F_STATUS) |
(1 << VIRTIO_NET_F_CTRL_VQ);
(1 << VIRTIO_NET_F_CTRL_VQ) |
(1 << VIRTIO_NET_F_CTRL_RX);
return features;
}
@ -127,6 +138,53 @@ static int virtio_net_handle_rx_mode(VirtIONet *n, uint8_t cmd,
return VIRTIO_NET_OK;
}
static int virtio_net_handle_mac(VirtIONet *n, uint8_t cmd,
VirtQueueElement *elem)
{
struct virtio_net_ctrl_mac mac_data;
if (cmd != VIRTIO_NET_CTRL_MAC_TABLE_SET || elem->out_num != 3 ||
elem->out_sg[1].iov_len < sizeof(mac_data) ||
elem->out_sg[2].iov_len < sizeof(mac_data))
return VIRTIO_NET_ERR;
n->mac_table.in_use = 0;
memset(n->mac_table.macs, 0, MAC_TABLE_ENTRIES * ETH_ALEN);
mac_data.entries = ldl_le_p(elem->out_sg[1].iov_base);
if (sizeof(mac_data.entries) +
(mac_data.entries * ETH_ALEN) > elem->out_sg[1].iov_len)
return VIRTIO_NET_ERR;
if (mac_data.entries <= MAC_TABLE_ENTRIES) {
memcpy(n->mac_table.macs, elem->out_sg[1].iov_base + sizeof(mac_data),
mac_data.entries * ETH_ALEN);
n->mac_table.in_use += mac_data.entries;
} else {
n->promisc = 1;
return VIRTIO_NET_OK;
}
mac_data.entries = ldl_le_p(elem->out_sg[2].iov_base);
if (sizeof(mac_data.entries) +
(mac_data.entries * ETH_ALEN) > elem->out_sg[2].iov_len)
return VIRTIO_NET_ERR;
if (mac_data.entries) {
if (n->mac_table.in_use + mac_data.entries <= MAC_TABLE_ENTRIES) {
memcpy(n->mac_table.macs + (n->mac_table.in_use * ETH_ALEN),
elem->out_sg[2].iov_base + sizeof(mac_data),
mac_data.entries * ETH_ALEN);
n->mac_table.in_use += mac_data.entries;
} else
n->allmulti = 1;
}
return VIRTIO_NET_OK;
}
static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq)
{
VirtIONet *n = to_virtio_net(vdev);
@ -151,6 +209,8 @@ static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq)
if (ctrl.class == VIRTIO_NET_CTRL_RX_MODE)
status = virtio_net_handle_rx_mode(n, ctrl.cmd, &elem);
else if (ctrl.class == VIRTIO_NET_CTRL_MAC)
status = virtio_net_handle_mac(n, ctrl.cmd, &elem);
stb_p(elem.in_sg[elem.in_num - 1].iov_base, status);
@ -226,6 +286,7 @@ static int receive_filter(VirtIONet *n, const uint8_t *buf, int size)
{
static const uint8_t bcast[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
uint8_t *ptr = (uint8_t *)buf;
int i;
if (n->promisc)
return 1;
@ -244,6 +305,11 @@ static int receive_filter(VirtIONet *n, const uint8_t *buf, int size)
if (!memcmp(ptr, n->mac, ETH_ALEN))
return 1;
for (i = 0; i < n->mac_table.in_use; i++) {
if (!memcmp(ptr, &n->mac_table.macs[i * ETH_ALEN], ETH_ALEN))
return 1;
}
return 0;
}
@ -406,6 +472,8 @@ static void virtio_net_save(QEMUFile *f, void *opaque)
qemu_put_be16(f, n->status);
qemu_put_be32(f, n->promisc);
qemu_put_be32(f, n->allmulti);
qemu_put_be32(f, n->mac_table.in_use);
qemu_put_buffer(f, n->mac_table.macs, n->mac_table.in_use * ETH_ALEN);
}
static int virtio_net_load(QEMUFile *f, void *opaque, int version_id)
@ -429,6 +497,19 @@ static int virtio_net_load(QEMUFile *f, void *opaque, int version_id)
n->allmulti = qemu_get_be32(f);
}
if (version_id >= 5) {
n->mac_table.in_use = qemu_get_be32(f);
/* MAC_TABLE_ENTRIES may be different from the saved image */
if (n->mac_table.in_use <= MAC_TABLE_ENTRIES) {
qemu_get_buffer(f, n->mac_table.macs,
n->mac_table.in_use * ETH_ALEN);
} else if (n->mac_table.in_use) {
qemu_fseek(f, n->mac_table.in_use * ETH_ALEN, SEEK_CUR);
n->promisc = 1;
n->mac_table.in_use = 0;
}
}
if (n->tx_timer_active) {
qemu_mod_timer(n->tx_timer,
qemu_get_clock(vm_clock) + TX_TIMER_INTERVAL);
@ -474,6 +555,10 @@ void virtio_net_init(PCIBus *bus, NICInfo *nd, int devfn)
n->mergeable_rx_bufs = 0;
n->promisc = 1; /* for compatibility */
n->mac_table.macs = qemu_mallocz(MAC_TABLE_ENTRIES * ETH_ALEN);
if (!n->mac_table.macs)
return;
register_savevm("virtio-net", virtio_net_id++, VIRTIO_NET_VM_VERSION,
virtio_net_save, virtio_net_load, n);
}

View File

@ -113,4 +113,26 @@ typedef uint8_t virtio_net_ctrl_ack;
#define VIRTIO_NET_CTRL_RX_MODE_PROMISC 0
#define VIRTIO_NET_CTRL_RX_MODE_ALLMULTI 1
/*
* Control the MAC filter table.
*
* The MAC filter table is managed by the hypervisor, the guest should
* assume the size is infinite. Filtering should be considered
* non-perfect, ie. based on hypervisor resources, the guest may
* received packets from sources not specified in the filter list.
*
* In addition to the class/cmd header, the TABLE_SET command requires
* two out scatterlists. Each contains a 4 byte count of entries followed
* by a concatenated byte stream of the ETH_ALEN MAC addresses. The
* first sg list contains unicast addresses, the second is for multicast.
* This functionality is present if the VIRTIO_NET_F_CTRL_RX feature
* is available.
*/
struct virtio_net_ctrl_mac {
uint32_t entries;
uint8_t macs[][ETH_ALEN];
};
#define VIRTIO_NET_CTRL_MAC 1
#define VIRTIO_NET_CTRL_MAC_TABLE_SET 0
#endif