[Qemu-devel] [PATCH v4 7/9] Packet abstraction used by VMWARE network devices

[Dmitry Fleytman]

Signed-off-by: Dmitry Fleytman <address@hidden>
Signed-off-by: Yan Vugenfirer <address@hidden>
---
 hw/vmxnet_pkt.c | 1243 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 hw/vmxnet_pkt.h |  479 +++++++++++++++++++++
 2 files changed, 1722 insertions(+), 0 deletions(-)
 create mode 100644 hw/vmxnet_pkt.c
 create mode 100644 hw/vmxnet_pkt.h

diff --git a/hw/vmxnet_pkt.c b/hw/vmxnet_pkt.c
new file mode 100644
index 0000000..5fe2672
--- /dev/null
+++ b/hw/vmxnet_pkt.c
@@ -0,0 +1,1243 @@
+/*
+ * QEMU VMWARE VMXNET* paravirtual NICs - packets abstractions
+ *
+ * Copyright (c) 2012 Ravello Systems LTD (http://ravellosystems.com)
+ *
+ * Developed by Daynix Computing LTD (http://www.daynix.com)
+ *
+ * Authors:
+ * Dmitry Fleytman <address@hidden>
+ * Tamir Shomer <address@hidden>
+ * Yan Vugenfirer <address@hidden>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ */
+
+#include "vmxnet_pkt.h"
+#include "vmxnet_utils.h"
+#include "iov.h"
+
+#include "net/checksum.h"
+
+/*=============================================================================
+ *=============================================================================
+ *
+ *                            TX CODE
+ *
+ *=============================================================================
+ *===========================================================================*/
+
+enum {
+    VMXNET_TX_PKT_VHDR_FRAG = 0,
+    VMXNET_TX_PKT_L2HDR_FRAG,
+    VMXNET_TX_PKT_L3HDR_FRAG,
+    VMXNET_TX_PKT_PL_START_FRAG
+};
+
+/* TX packet private context */
+typedef struct _Vmxnet_TxPkt {
+    struct virtio_net_hdr virt_hdr;
+    bool has_virt_hdr;
+
+    struct iovec *vec;
+
+    uint8_t l2_hdr[ETH_MAX_L2_HDR_LEN];
+    uint8_t l3_hdr[ETH_MAX_L3_HDR_LEN];
+
+    uint32_t payload_len;
+
+    uint32_t payload_frags;
+    uint32_t max_payload_frags;
+
+    uint16_t hdr_len;
+    eth_pkt_types_e packet_type;
+    uint16_t l3_proto;
+} Vmxnet_TxPkt;
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_init
+ *
+ * Desc: Init function for tx packet functionality.
+ *
+ * Params:  (OUT) pkt - private handle.
+ *          (IN) max_frags - max tx ip fragments.
+ *          (IN) has_virt_hdr - device uses virtio header.
+ *
+ * Return:  0 on success, -1 on error
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+int vmxnet_tx_pkt_init(Vmxnet_TxPkt_h *pkt, uint32_t max_frags,
+    bool has_virt_hdr)
+{
+    int rc = 0;
+
+    Vmxnet_TxPkt *p = g_malloc(sizeof *p);
+    if (!p) {
+        rc = -1;
+        goto Exit;
+    }
+
+    memset(p, 0, sizeof *p);
+
+    p->vec = g_malloc((sizeof *p->vec) *
+        (max_frags + VMXNET_TX_PKT_PL_START_FRAG));
+    if (!p->vec) {
+        rc = -1;
+        goto Exit;
+    }
+
+    p->max_payload_frags = max_frags;
+    p->has_virt_hdr = has_virt_hdr;
+    p->vec[VMXNET_TX_PKT_VHDR_FRAG].iov_base = &p->virt_hdr;
+    p->vec[VMXNET_TX_PKT_VHDR_FRAG].iov_len =
+        p->has_virt_hdr ? sizeof p->virt_hdr : 0;
+    p->vec[VMXNET_TX_PKT_L2HDR_FRAG].iov_base = &p->l2_hdr;
+    p->vec[VMXNET_TX_PKT_L3HDR_FRAG].iov_base = &p->l3_hdr;
+
+    *pkt = p;
+
+Exit:
+    if (rc) {
+        vmxnet_tx_pkt_uninit(p);
+    }
+    return rc;
+}
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_uninit
+ *
+ * Desc: Clean all tx packet resources.
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  nothing
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+void vmxnet_tx_pkt_uninit(Vmxnet_TxPkt_h pkt)
+{
+    Vmxnet_TxPkt *p = (Vmxnet_TxPkt *)pkt;
+
+    if (p) {
+        if (p->vec) {
+            g_free(p->vec);
+        }
+
+        g_free(p);
+    }
+}
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_update_ip_checksums
+ *
+ * Desc: fix ip header fields and calculate checksums needed.
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  Nothing.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+void vmxnet_tx_pkt_update_ip_checksums(Vmxnet_TxPkt_h pkt)
+{
+    uint16_t csum;
+    Vmxnet_TxPkt *p = (Vmxnet_TxPkt *)pkt;
+    assert(p);
+    uint8_t gso_type = p->virt_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN;
+    struct ip_header *ip_hdr;
+    target_phys_addr_t payload = (target_phys_addr_t)
+        (uint64_t) p->vec[VMXNET_TX_PKT_PL_START_FRAG].iov_base;
+
+    if (VIRTIO_NET_HDR_GSO_TCPV4 != gso_type &&
+        VIRTIO_NET_HDR_GSO_UDP != gso_type) {
+        return;
+    }
+
+    ip_hdr = p->vec[VMXNET_TX_PKT_L3HDR_FRAG].iov_base;
+
+    if (p->payload_len + p->vec[VMXNET_TX_PKT_L3HDR_FRAG].iov_len >
+        ETH_MAX_IP_DGRAM_LEN) {
+        return;
+    }
+
+    ip_hdr->ip_len = cpu_to_be16(p->payload_len +
+        p->vec[VMXNET_TX_PKT_L3HDR_FRAG].iov_len);
+
+    /* Calculate IP header checksum                    */
+    ip_hdr->ip_sum = 0;
+    csum = net_raw_checksum((uint8_t *)ip_hdr,
+        p->vec[VMXNET_TX_PKT_L3HDR_FRAG].iov_len);
+    ip_hdr->ip_sum = cpu_to_be16(csum);
+
+    /* Calculate IP pseudo header checksum             */
+    csum = cpu_to_be16(eth_calc_pseudo_hdr_csum(ip_hdr, p->payload_len));
+    cpu_physical_memory_write(payload + p->virt_hdr.csum_offset,
+                              &csum, sizeof(csum));
+}
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_get_l4_proto
+ *
+ * Desc: get l4 protocol.
+ *
+ * Params:  (IN) p - module context
+ *
+ * Return: l4 protocol
+ *
+ * Scope: Local
+ *
+ *****************************************************************************/
+static uint8_t vmxnet_tx_pkt_get_l4_proto(Vmxnet_TxPkt *p)
+{
+    struct ip_header *ip_hdr;
+    struct ip6_header *ip6_hdr;
+
+    if (!p->vec[VMXNET_TX_PKT_L3HDR_FRAG].iov_len) {
+        return 0;
+    }
+
+    if (ETH_P_IP == p->l3_proto) {
+        ip_hdr = p->vec[VMXNET_TX_PKT_L3HDR_FRAG].iov_base;
+        return ip_hdr->ip_p;
+    } else if (p->l3_proto == ETH_P_IPV6) {
+        ip6_hdr = p->vec[VMXNET_TX_PKT_L3HDR_FRAG].iov_base;
+        return ip6_hdr->ip6_nxt;
+    }
+
+    return 0;
+}
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_calculate_hdr_len
+ *
+ * Desc: store l2 and l3 headers length.
+ *
+ * Params:  (IN) p - module context
+ *
+ * Return: nothing
+ *
+ * Scope: Local
+ *
+ *****************************************************************************/
+static void vmxnet_tx_pkt_calculate_hdr_len(Vmxnet_TxPkt *p)
+{
+    p->hdr_len = p->vec[VMXNET_TX_PKT_L2HDR_FRAG].iov_len +
+        p->vec[VMXNET_TX_PKT_L3HDR_FRAG].iov_len;
+}
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_prepare
+ *
+ * Desc: populates headers and parses them to gether some metadata for later
+ *       use.
+ *
+ * Params:  (IN) pkt - private handle.
+ *          (IN) pa - physical address of tx data
+ *          (IN) len - length of data
+ *
+ * Return:  number of bytes populated by the function.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+size_t vmxnet_tx_pkt_prepare(Vmxnet_TxPkt_h pkt, target_phys_addr_t pa,
+    size_t len)
+{
+    Vmxnet_TxPkt *p = (Vmxnet_TxPkt *)pkt;
+    /* some pointers that my lines stay nice and short. */
+    void *l2_iov_base = NULL, *l3_iov_base = NULL;
+    size_t *l2_iov_len = NULL, *l3_iov_len = NULL;
+    assert(p);
+
+    l2_iov_base = p->vec[VMXNET_TX_PKT_L2HDR_FRAG].iov_base;
+    l2_iov_len = &p->vec[VMXNET_TX_PKT_L2HDR_FRAG].iov_len;
+    l3_iov_base = p->vec[VMXNET_TX_PKT_L3HDR_FRAG].iov_base;
+    l3_iov_len = &p->vec[VMXNET_TX_PKT_L3HDR_FRAG].iov_len;
+
+    cpu_physical_memory_read(pa, l2_iov_base, ETH_MAX_L2_HDR_LEN);
+
+    *l2_iov_len = eth_get_l2_hdr_length(l2_iov_base);
+
+    p->l3_proto = eth_get_l3_proto(l2_iov_base, *l2_iov_len);
+
+    switch (p->l3_proto) {
+    case ETH_P_IP:
+        assert(len >= *l2_iov_len + sizeof(struct ip_header));
+
+        cpu_physical_memory_read(pa + *l2_iov_len, l3_iov_base,
+            sizeof(struct ip_header));
+        *l3_iov_len = IP_HDR_GET_LEN(l3_iov_base);
+
+        /* handle optional header data */
+        if (*l3_iov_len > sizeof(struct ip_header)) {
+            cpu_physical_memory_read(
+                pa + *l2_iov_len + sizeof(struct ip_header),
+                l3_iov_base + sizeof(struct ip_header),
+                *l3_iov_len - sizeof(struct ip_header));
+        }
+        break;
+
+    case ETH_P_IPV6:
+        *l3_iov_len = sizeof(struct ip6_header);
+        if (len < *l2_iov_len + *l3_iov_len) {
+            /*
+             * no ipv6 header in this buffer. can happen in vmxnet,
+             * when zero copy is enabled
+             */
+            *l3_iov_len = 0;
+            break;
+        }
+        cpu_physical_memory_read(pa + *l2_iov_len, l3_iov_base, *l3_iov_len);
+        break;
+
+    default:
+        *l3_iov_len = 0;
+        break;
+    }
+
+    vmxnet_tx_pkt_calculate_hdr_len(p);
+    p->packet_type = get_eth_packet_type(l2_iov_base);
+
+    /* Return amount of data populated into vec */
+    return *l2_iov_len + *l3_iov_len;
+}
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_get_vhdr
+ *
+ * Desc: get virtio header.
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  virtio header
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+struct virtio_net_hdr *vmxnet_tx_pkt_get_vhdr(Vmxnet_TxPkt_h pkt)
+{
+    Vmxnet_TxPkt *p = (Vmxnet_TxPkt *)pkt;
+    assert(p);
+    return &p->virt_hdr;
+}
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_get_gso_type
+ *
+ * Desc: calculate gso type.
+ *
+ * Params:  (IN) pkt - private handle.
+ *          (IN) tso_enable
+ *
+ * Return:  gso type.
+ *
+ * Scope: Local
+ *
+ *****************************************************************************/
+static uint8_t vmxnet_tx_pkt_get_gso_type(Vmxnet_TxPkt *p, bool tso_enable)
+{
+    uint8_t rc = VIRTIO_NET_HDR_GSO_NONE;
+    uint16_t l3_proto;
+
+    l3_proto = eth_get_l3_proto(p->vec[VMXNET_TX_PKT_L2HDR_FRAG].iov_base,
+        p->vec[VMXNET_TX_PKT_L2HDR_FRAG].iov_len);
+
+    if (!tso_enable) {
+        goto Exit;
+    }
+
+    rc = eth_get_gso_type(l3_proto, p->vec[VMXNET_TX_PKT_L3HDR_FRAG].iov_base);
+
+Exit:
+    return rc;
+}
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_build_vheader
+ *
+ * Desc: build virtio header. (will be stored in module context)
+ *
+ * Params:  (IN) pkt - private handle.
+ *          (IN) tso_enable
+ *          (IN) csum_enable (has to be enabled if tso_enable is true)
+ *          (IN) gso_size - (relevent only if tso enabled)
+ *
+ * Return:  nothing
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+void vmxnet_tx_pkt_build_vheader(Vmxnet_TxPkt_h pkt, bool tso_enable,
+    bool csum_enable, uint32_t gso_size)
+{
+    Vmxnet_TxPkt *p = (Vmxnet_TxPkt *)pkt;
+    struct tcp_hdr l4hdr;
+    target_phys_addr_t l4hdr_pa;
+    assert(p);
+
+    /* csum has to be enabled if tso is. */
+    assert(csum_enable || !tso_enable);
+
+    p->virt_hdr.gso_type = vmxnet_tx_pkt_get_gso_type(p, tso_enable);
+
+    switch (p->virt_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
+    case VIRTIO_NET_HDR_GSO_NONE:
+        p->virt_hdr.hdr_len = 0;
+        p->virt_hdr.gso_size = 0;
+        break;
+
+    case VIRTIO_NET_HDR_GSO_UDP:
+        p->virt_hdr.gso_size = IP_FRAG_ALIGN_SIZE(gso_size);
+        p->virt_hdr.hdr_len = p->hdr_len + sizeof(struct udp_header);
+        break;
+
+    case VIRTIO_NET_HDR_GSO_TCPV4:
+    case VIRTIO_NET_HDR_GSO_TCPV6:
+        l4hdr_pa = (target_phys_addr_t)
+            (uint64_t) p->vec[VMXNET_TX_PKT_PL_START_FRAG].iov_base;
+        cpu_physical_memory_read(l4hdr_pa, &l4hdr, sizeof(l4hdr));
+        p->virt_hdr.hdr_len = p->hdr_len + l4hdr.th_off * sizeof(uint32_t);
+        p->virt_hdr.gso_size = IP_FRAG_ALIGN_SIZE(gso_size);
+        break;
+
+    default:
+        assert(false);
+    }
+
+    if (csum_enable) {
+        p->virt_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
+
+        p->virt_hdr.csum_start = p->vec[VMXNET_TX_PKT_L2HDR_FRAG].iov_len +
+            p->vec[VMXNET_TX_PKT_L3HDR_FRAG].iov_len;
+        switch (vmxnet_tx_pkt_get_l4_proto(p)) {
+        case IP_PROTO_TCP:
+            p->virt_hdr.csum_offset = offsetof(struct tcp_hdr, th_sum);
+            break;
+        case IP_PROTO_UDP:
+            p->virt_hdr.csum_offset = offsetof(struct udp_hdr, uh_sum);
+            break;
+        default:
+            assert(false);
+            break;
+        }
+    }
+}
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_setup_vlan_header
+ *
+ * Desc: updates vlan tag, and adds vlan header in case it is missing.
+ *
+ * Params:  (IN) pkt - private handle.
+ *          (IN) vlan
+ *
+ * Return:  Nothing
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+void vmxnet_tx_pkt_setup_vlan_header(Vmxnet_TxPkt_h pkt, uint16_t vlan)
+{
+    bool is_new;
+    Vmxnet_TxPkt *p = (Vmxnet_TxPkt *)pkt;
+    assert(p);
+
+    eth_setup_vlan_headers(p->vec[VMXNET_TX_PKT_L2HDR_FRAG].iov_base,
+        vlan, &is_new);
+
+    /* update l2hdrlen */
+    if (is_new) {
+        p->hdr_len += sizeof(struct vlan_header);
+        p->vec[VMXNET_TX_PKT_L2HDR_FRAG].iov_len += sizeof(struct vlan_header);
+    }
+}
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_add_fragment
+ *
+ * Desc: populate fragment into pkt context.
+ *
+ * Params:  (IN) pkt - private handle.
+ *          (IN) pa - physical address of fragment
+ *          (IN) len - length of fragment
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+void vmxnet_tx_pkt_add_fragment(Vmxnet_TxPkt_h pkt, target_phys_addr_t pa,
+    size_t len)
+{
+    Vmxnet_TxPkt *p = (Vmxnet_TxPkt *)pkt;
+    int abs_frag_num = p->payload_frags + VMXNET_TX_PKT_PL_START_FRAG;
+    assert(p);
+
+    if (!len) {
+        return;
+    }
+
+    assert(p->max_payload_frags > p->payload_frags);
+
+    p->vec[abs_frag_num].iov_base = (void *) (uint64_t) pa;
+    p->vec[abs_frag_num].iov_len = len;
+    p->payload_frags++;
+    p->payload_len += len;
+}
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_get_packet_type
+ *
+ * Desc: returns packet type
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  packet type.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+eth_pkt_types_e vmxnet_tx_pkt_get_packet_type(Vmxnet_TxPkt_h pkt)
+{
+    Vmxnet_TxPkt *p = (Vmxnet_TxPkt *)pkt;
+    assert(p);
+
+    return p->packet_type;
+}
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_get_total_len
+ *
+ * Desc: Returns the length of all populated data.
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  length of populated data.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+size_t vmxnet_tx_pkt_get_total_len(Vmxnet_TxPkt_h pkt)
+{
+    Vmxnet_TxPkt *p = (Vmxnet_TxPkt *)pkt;
+    assert(p);
+
+    return p->hdr_len + p->payload_len;
+}
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_unmap
+ *
+ * Desc: unmap all populated headers and fragments from iovec.
+ *
+ * Params:  (IN) p - private context.
+ *
+ * Return:  Nothing.
+ *
+ * Scope: Local
+ *
+ *****************************************************************************/
+static void vmxnet_tx_pkt_unmap(Vmxnet_TxPkt *p)
+{
+    int i;
+
+    for (i = VMXNET_TX_PKT_PL_START_FRAG;
+        i < p->payload_frags + VMXNET_TX_PKT_PL_START_FRAG; i++) {
+        cpu_physical_memory_unmap(p->vec[i].iov_base, p->vec[i].iov_len,
+            false, p->vec[i].iov_len);
+    }
+}
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_map
+ *
+ * Desc: map all populated headers and fragments into iovec.
+ *
+ * Params:  (IN) p - private context.
+ *          (OUT) mapped_fragments - length of iovec.
+ *
+ * Return:  iovec head. NULL on error.
+ *
+ * Scope: local
+ *
+ *****************************************************************************/
+static void *vmxnet_tx_pkt_map(Vmxnet_TxPkt *p, uint32_t *mapped_fragments)
+{
+    int i;
+
+    for (i = VMXNET_TX_PKT_PL_START_FRAG;
+        i < p->payload_frags + VMXNET_TX_PKT_PL_START_FRAG; i++) {
+        target_phys_addr_t mapped_len = p->vec[i].iov_len;
+        size_t orig_len = p->vec[i].iov_len;
+        p->vec[i].iov_base =
+            cpu_physical_memory_map((target_phys_addr_t) (uint64_t)
+                p->vec[i].iov_base, &mapped_len, false);
+        p->vec[i].iov_len = mapped_len;
+
+        if ((NULL == p->vec[i].iov_base) || (orig_len != mapped_len)) {
+            p->payload_frags = i + !!p->vec[i].iov_base;
+            vmxnet_tx_pkt_unmap(p);
+            return NULL;
+        }
+    }
+
+    *mapped_fragments = p->payload_frags + VMXNET_TX_PKT_PL_START_FRAG;
+    return p->vec;
+}
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_dump
+ *
+ * Desc: Prints packet data if debug is enabled
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  Nothing.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+void vmxnet_tx_pkt_dump(Vmxnet_TxPkt_h pkt)
+{
+#ifdef VMXNET_TX_PKT_DEBUG
+    Vmxnet_TxPkt *p = (Vmxnet_TxPkt *)pkt;
+    assert(p);
+
+    printf("TX PKT: hdr_len: %d, pkt_type: 0x%X, l2hdr_len: %lu, "
+        "l3hdr_len: %lu, payload_len: %u\n", p->hdr_len, p->packet_type,
+        p->vec[VMXNET_TX_PKT_L2HDR_FRAG].iov_len,
+        p->vec[VMXNET_TX_PKT_L3HDR_FRAG].iov_len, p->payload_len);
+#endif
+}
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_reset
+ *
+ * Desc: reset tx packet private context. (needed to be called between packets)
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  Nothing.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+void vmxnet_tx_pkt_reset(Vmxnet_TxPkt_h pkt)
+{
+    Vmxnet_TxPkt *p = (Vmxnet_TxPkt *)pkt;
+    int i;
+
+    /* no assert, as reset can be called before tx_pkt_init */
+    if (!p) {
+        return;
+    }
+
+    memset(&p->virt_hdr, 0, sizeof(p->virt_hdr));
+
+    assert(p->vec);
+    for (i = VMXNET_TX_PKT_L2HDR_FRAG; i < p->max_payload_frags; i++) {
+        p->vec[i].iov_len = 0;
+    }
+
+    p->payload_len = 0;
+    p->payload_frags = 0;
+    p->hdr_len = 0;
+    p->packet_type = 0;
+}
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_do_sw_csum
+ *
+ * Desc: Calculate l4 csum and put it in hdr.
+ *
+ * Params:  (IN) p - private handle.
+ *
+ * Return:  nothing.
+ *
+ * Scope: Local
+ *
+ *****************************************************************************/
+static void vmxnet_tx_pkt_do_sw_csum(Vmxnet_TxPkt *p)
+{
+    struct iovec *iov = &p->vec[VMXNET_TX_PKT_L2HDR_FRAG];
+    uint32_t csum_cntr;
+    uint16_t csum = 0;
+    /* num of iovec without vhdr */
+    uint32_t iov_len = p->payload_frags + VMXNET_TX_PKT_PL_START_FRAG - 1;
+    uint16_t csl;
+    struct ip_header *iphdr;
+    size_t csum_offset = p->virt_hdr.csum_start + p->virt_hdr.csum_offset;
+
+    /* Put zero to checksum field */
+    iov_from_buf(iov, iov_len, &csum, csum_offset, sizeof csum);
+
+    /* Calculate L4 TCP/UDP checksum */
+    csl = p->payload_len;
+
+    /* data checksum */
+    csum_cntr = iov_net_csum_add(iov, iov_len, p->virt_hdr.csum_start, csl);
+    /* add pseudo header to csum */
+    iphdr = p->vec[VMXNET_TX_PKT_L3HDR_FRAG].iov_base;
+    csum_cntr += eth_calc_pseudo_hdr_csum(iphdr, csl);
+
+    /* Put the checksum obtained into the packet */
+    csum = cpu_to_be16(net_checksum_finish(csum_cntr));
+    iov_from_buf(iov, iov_len, &csum, csum_offset, sizeof csum);
+}
+
+enum {
+    VMXNET_TX_PKT_FRAGMENT_L2_HDR_POS = 0,
+    VMXNET_TX_PKT_FRAGMENT_L3_HDR_POS,
+    VMXNET_TX_PKT_FRAGMENT_HEADER_NUM
+};
+
+#define VMXNET_MAX_FRAG_SG_LIST (64)
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_fetch_fragment
+ *
+ * Desc: Copy data from packet to fragment iov.
+ *
+ * Params:  (IN) p - private context.
+ *          (IN/OUT) src_idx - current index in packet iov
+ *          (IN/OUT) src_offset - current offset in iov member
+ *          (OUT) dst - fragment iov
+ *          (OUT) dst_idx - the used length of the fragment iov
+ *                          (+1 as this is an index)
+ *
+ * Return:  number of bytes sent.
+ *
+ * Scope: Local
+ *
+ *****************************************************************************/
+static size_t vmxnet_tx_pkt_fetch_fragment(Vmxnet_TxPkt *p, int *src_idx,
+    size_t *src_offset, struct iovec *dst, int *dst_idx)
+{
+    size_t fetched = 0;
+    struct iovec *src = p->vec;
+
+    *dst_idx = VMXNET_TX_PKT_FRAGMENT_HEADER_NUM;
+
+    while (fetched < p->virt_hdr.gso_size) {
+
+        /* no more place in fragment iov */
+        if (*dst_idx == VMXNET_MAX_FRAG_SG_LIST) {
+            break;
+        }
+
+        /* no more data in iovec */
+        if (*src_idx == (p->payload_frags + VMXNET_TX_PKT_PL_START_FRAG)) {
+            break;
+        }
+
+
+        dst[*dst_idx].iov_base = src[*src_idx].iov_base + *src_offset;
+        dst[*dst_idx].iov_len = MIN(src[*src_idx].iov_len - *src_offset,
+            p->virt_hdr.gso_size - fetched);
+
+        *src_offset += dst[*dst_idx].iov_len;
+        fetched += dst[*dst_idx].iov_len;
+
+        if (*src_offset == src[*src_idx].iov_len) {
+            *src_offset = 0;
+            (*src_idx)++;
+        }
+
+        (*dst_idx)++;
+    }
+
+    return fetched;
+}
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_do_sw_fragmentation
+ *
+ * Desc: Preformes softwere fragmentation of the packet and sends in to qemu
+ *
+ * Params:  (IN) p - private context.
+ *          (IN) vc - VLANClientState.
+ *
+ * Return:  number of bytes sent.
+ *
+ * Scope: Local
+ *
+ *****************************************************************************/
+static size_t vmxnet_tx_pkt_do_sw_fragmentation(Vmxnet_TxPkt *p,
+    VLANClientState *vc)
+{
+    struct iovec fragment[VMXNET_MAX_FRAG_SG_LIST];
+    size_t fragment_len = 0;
+    bool more_frags = false;
+    /* some poiners for shorter code */
+    void *l2_iov_base, *l3_iov_base;
+    size_t l2_iov_len, l3_iov_len;
+    int src_idx =  VMXNET_TX_PKT_PL_START_FRAG, dst_idx;
+    size_t src_offset = 0;
+    size_t bytes_sent = 0;
+    size_t fragment_offset = 0;
+
+    l2_iov_base = p->vec[VMXNET_TX_PKT_L2HDR_FRAG].iov_base;
+    l2_iov_len = p->vec[VMXNET_TX_PKT_L2HDR_FRAG].iov_len;
+    l3_iov_base = p->vec[VMXNET_TX_PKT_L3HDR_FRAG].iov_base;
+    l3_iov_len = p->vec[VMXNET_TX_PKT_L3HDR_FRAG].iov_len;
+
+    /* Copy headers */
+    fragment[VMXNET_TX_PKT_FRAGMENT_L2_HDR_POS].iov_base = l2_iov_base;
+    fragment[VMXNET_TX_PKT_FRAGMENT_L2_HDR_POS].iov_len = l2_iov_len;
+    fragment[VMXNET_TX_PKT_FRAGMENT_L3_HDR_POS].iov_base = l3_iov_base;
+    fragment[VMXNET_TX_PKT_FRAGMENT_L3_HDR_POS].iov_len = l3_iov_len;
+
+
+    /* Put as much data as possible and send */
+    do {
+        fragment_len = vmxnet_tx_pkt_fetch_fragment(p, &src_idx, &src_offset,
+            fragment, &dst_idx);
+
+        more_frags = (fragment_offset + fragment_len < p->payload_len);
+
+        eth_setup_ip4_fragmentation(l2_iov_base, l2_iov_len, l3_iov_base,
+            l3_iov_len, fragment_len, fragment_offset, more_frags);
+
+        eth_fix_ip4_checksum(l3_iov_base, l3_iov_len);
+
+        bytes_sent += qemu_sendv_packet(vc, fragment, dst_idx);
+
+        fragment_offset += fragment_len;
+
+    } while (more_frags);
+
+    return bytes_sent;
+}
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_send
+ *
+ * Desc: Send packet to qemu. handles sw offloads if vhdr is not supported.
+ *
+ * Params:  (IN) pkt - private handle.
+ *          (IN) vc - VLANClientState.
+ *
+ * Return:  number of bytes sent.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+size_t vmxnet_tx_pkt_send(Vmxnet_TxPkt_h pkt, VLANClientState *vc)
+{
+    void *iovec = NULL;
+    uint32_t iovec_size;
+    size_t bytes_sent = 0;
+    Vmxnet_TxPkt *p = (Vmxnet_TxPkt *)pkt;
+    assert(p);
+
+    iovec = vmxnet_tx_pkt_map(p, &iovec_size);
+    if (!iovec) {
+        goto Exit;
+    }
+
+    if (!p->has_virt_hdr && p->virt_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
+        vmxnet_tx_pkt_do_sw_csum(p);
+    }
+
+    if (p->has_virt_hdr || VIRTIO_NET_HDR_GSO_NONE == p->virt_hdr.gso_type) {
+        bytes_sent = qemu_sendv_packet(vc, iovec, iovec_size);
+        goto Exit;
+    }
+
+    bytes_sent = vmxnet_tx_pkt_do_sw_fragmentation(p, vc);
+
+Exit:
+    vmxnet_tx_pkt_unmap(p);
+    return bytes_sent;
+}
+
+/*=============================================================================
+ *=============================================================================
+ *
+ *                            RX CODE
+ *
+ *=============================================================================
+ *===========================================================================*/
+
+/*
+ * RX packet may contain up to 2 fragments - rebuilt eth header
+ * in case of VLAN tag stripping
+ * and payload received from QEMU - in any case
+ */
+#define VMXNET_MAX_RX_PACKET_FRAGMENTS (2)
+
+typedef struct Vmxnet_RxPkt {
+    struct virtio_net_hdr virt_hdr;
+    struct eth_header eth_hdr;
+    struct iovec vec[VMXNET_MAX_RX_PACKET_FRAGMENTS];
+    uint16 vec_len;
+    uint32_t tot_len;
+    uint16_t vlan_tag;
+    bool vlan_stripped;
+    bool has_virt_hdr;
+    eth_pkt_types_e packet_type;
+} Vmxnet_RxPkt;
+
+/******************************************************************************
+ *
+ * Function: vmxnet_rx_pkt_init
+ *
+ * Desc: Init function for rx packet functionality.
+ *
+ * Params:  (OUT) pkt - private handle.
+ *          (IN) has_virt_hdr - device uses virtio header.
+ *
+ * Return:  0 on success, -1 on error
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+int vmxnet_rx_pkt_init(Vmxnet_RxPkt_h *pkt, bool has_virt_hdr)
+{
+    int rc = 0;
+
+    Vmxnet_RxPkt *p = g_malloc(sizeof *p);
+    if (!p) {
+        rc = -1;
+        goto Exit;
+    }
+
+    memset(p, 0, sizeof *p);
+    p->has_virt_hdr = has_virt_hdr;
+
+    *pkt = p;
+
+Exit:
+    if (rc) {
+        vmxnet_rx_pkt_uninit(p);
+    }
+    return rc;
+}
+
+/******************************************************************************
+ *
+ * Function: vmxnet_rx_pkt_uninit
+ *
+ * Desc: Clean all rx packet resources.
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  nothing
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+void vmxnet_rx_pkt_uninit(Vmxnet_RxPkt_h pkt)
+{
+    if (pkt) {
+        g_free(pkt);
+    }
+}
+
+/******************************************************************************
+ *
+ * Function: vmxnet_rx_pkt_get_vhdr
+ *
+ * Desc: returns virtio header stored in rx context.
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  virtio header
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+struct virtio_net_hdr *vmxnet_rx_pkt_get_vhdr(Vmxnet_RxPkt_h pkt)
+{
+    Vmxnet_RxPkt *p = (Vmxnet_RxPkt *)pkt;
+    assert(p);
+    return &p->virt_hdr;
+}
+
+/******************************************************************************
+ *
+ * Function: vmxnet_rx_pkt_attach_data
+ *
+ * Desc: Attach data to rx packet.
+ *
+ * Params:  (IN) pkt - private handle.
+ *          (IN) data
+ *          (IN) len
+ *          (IN) strip_vlan - should the module strip vlan from data.
+ *
+ * Return:  nothing.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+void vmxnet_rx_pkt_attach_data(Vmxnet_RxPkt_h pkt, const void *data, size_t 
len,
+    bool strip_vlan)
+{
+    Vmxnet_RxPkt *p = (Vmxnet_RxPkt *)pkt;
+    uint16_t vtag = 0;
+    uint16_t ploff;
+    assert(p);
+    p->vlan_stripped = false;
+
+    if (strip_vlan) {
+        p->vlan_stripped = eth_strip_vlan(&data, &p->eth_hdr, &ploff, &vtag);
+    }
+
+    if (p->vlan_stripped) {
+        p->vec[0].iov_base = &p->eth_hdr;
+        p->vec[0].iov_len = sizeof p->eth_hdr;
+        p->vec[1].iov_base = (uint8_t *) data + ploff;
+        p->vec[1].iov_len = len - ploff;
+        p->vec_len = 2;
+        p->tot_len = len - ploff + sizeof(struct eth_header);
+    } else {
+        p->vec[0].iov_base = (void *)data;
+        p->vec[0].iov_len = len;
+        p->vec_len = 1;
+        p->tot_len = len;
+    }
+
+    p->vlan_tag = vtag;
+}
+
+/******************************************************************************
+ *
+ * Function: vmxnet_rx_pkt_dump
+ *
+ * Desc: prints rx packet data if debug is enabled.
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  Nothing.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+void vmxnet_rx_pkt_dump(Vmxnet_RxPkt_h pkt)
+{
+#ifdef VMXNET_RX_PKT_DEBUG
+    Vmxnet_RxPkt *p = (Vmxnet_RxPkt *)pkt;
+    assert(p);
+
+    printf("RX PKT: tot_len: %d, vlan_stripped: %d, vlan_tag: %d\n",
+              p->tot_len, p->vlan_stripped, p->vlan_tag);
+#endif
+}
+
+/******************************************************************************
+ *
+ * Function: vmxnet_rx_pkt_set_packet_type
+ *
+ * Desc: save packet type in packet context
+ *
+ * Params:  (IN) pkt - private handle.
+ *          (IN) packet_type.
+ *
+ * Return:  Nothing.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+void vmxnet_rx_pkt_set_packet_type(Vmxnet_RxPkt_h pkt,
+    eth_pkt_types_e packet_type)
+{
+    Vmxnet_RxPkt *p = (Vmxnet_RxPkt *)pkt;
+    assert(p);
+
+    p->packet_type = packet_type;
+
+}
+
+/******************************************************************************
+ *
+ * Function: vmxnet_rx_pkt_get_packet_type
+ *
+ * Desc: returns packet type.
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  packet type.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+eth_pkt_types_e vmxnet_rx_pkt_get_packet_type(Vmxnet_RxPkt_h pkt)
+{
+    Vmxnet_RxPkt *p = (Vmxnet_RxPkt *)pkt;
+    assert(p);
+
+    return p->packet_type;
+}
+
+/******************************************************************************
+ *
+ * Function: vmxnet_rx_pkt_get_total_len
+ *
+ * Desc: returns total length of data attached to rx context.
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  nothing
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+size_t vmxnet_rx_pkt_get_total_len(Vmxnet_RxPkt_h pkt)
+{
+    Vmxnet_RxPkt *p = (Vmxnet_RxPkt *)pkt;
+    assert(p);
+
+    return p->tot_len;
+}
+
+/******************************************************************************
+ *
+ * Function: vmxnet_rx_pkt_get_iovec
+ *
+ * Desc: returns io vector that holds the attached data.
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  iovector.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+struct iovec *vmxnet_rx_pkt_get_iovec(Vmxnet_RxPkt_h pkt)
+{
+    Vmxnet_RxPkt *p = (Vmxnet_RxPkt *)pkt;
+    assert(p);
+
+    return p->vec;
+}
+
+/******************************************************************************
+ *
+ * Function: vmxnet_rx_pkt_set_vhdr
+ *
+ * Desc: copy passed phdr data to packet context.
+ *
+ * Params:  (IN) pkt - private handle.
+ *          (IN) vhdr - new vhdr data.
+ *
+ * Return:  Nothing.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+void vmxnet_rx_pkt_set_vhdr(Vmxnet_RxPkt_h pkt, struct virtio_net_hdr *vhdr)
+{
+    Vmxnet_RxPkt *p = (Vmxnet_RxPkt *)pkt;
+    assert(p);
+
+    memcpy(&p->virt_hdr, vhdr, sizeof p->virt_hdr);
+}
+
+/******************************************************************************
+ *
+ * Function: vmxnet_rx_pkt_is_vlan_stripped
+ *
+ * Desc: notifies caller if a vlan was stripped from the packet.
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  true if vlan vas stripped form the packet, false otherwize.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+bool vmxnet_rx_pkt_is_vlan_stripped(Vmxnet_RxPkt_h pkt)
+{
+    Vmxnet_RxPkt *p = (Vmxnet_RxPkt *)pkt;
+    assert(p);
+
+    return p->vlan_stripped;
+}
+
+/******************************************************************************
+ *
+ * Function: vmxnet_rx_pkt_has_virt_hdr
+ *
+ * Desc: notifies caller if the packet has virtio header
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  true if packet has virtio header, false otherwize.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+bool vmxnet_rx_pkt_has_virt_hdr(Vmxnet_RxPkt_h pkt)
+{
+    Vmxnet_RxPkt *p = (Vmxnet_RxPkt *)pkt;
+    assert(p);
+
+    return p->has_virt_hdr;
+}
+
+/******************************************************************************
+ *
+ * Function: vmxnet_rx_pkt_get_num_frags
+ *
+ * Desc: returns number of frags attached to the packet.
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  number of frags.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+uint16_t vmxnet_rx_pkt_get_num_frags(Vmxnet_RxPkt_h pkt)
+{
+    Vmxnet_RxPkt *p = (Vmxnet_RxPkt *)pkt;
+    assert(p);
+
+    return p->vec_len;
+}
+
+/******************************************************************************
+ *
+ * Function: vmxnet_rx_pkt_get_vlan_tag
+ *
+ * Desc: returns vlan tag.
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  vlan tag.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+uint16_t vmxnet_rx_pkt_get_vlan_tag(Vmxnet_RxPkt_h pkt)
+{
+    Vmxnet_RxPkt *p = (Vmxnet_RxPkt *)pkt;
+    assert(p);
+
+    return p->vlan_tag;
+}
diff --git a/hw/vmxnet_pkt.h b/hw/vmxnet_pkt.h
new file mode 100644
index 0000000..099bf1a
--- /dev/null
+++ b/hw/vmxnet_pkt.h
@@ -0,0 +1,479 @@
+/*
+ * QEMU VMWARE VMXNET* paravirtual NICs - packets abstractions
+ *
+ * Copyright (c) 2012 Ravello Systems LTD (http://ravellosystems.com)
+ *
+ * Developed by Daynix Computing LTD (http://www.daynix.com)
+ *
+ * Authors:
+ * Dmitry Fleytman <address@hidden>
+ * Tamir Shomer <address@hidden>
+ * Yan Vugenfirer <address@hidden>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ */
+
+#ifndef VMXNET_PKT_H
+#define VMXNET_PKT_H
+
+#include "stdint.h"
+#include "stdbool.h"
+#include "vmxnet_utils.h"
+
+/* defines to enable packet dump functions */
+/*#define VMXNET_TX_PKT_DEBUG*/
+/*#define VMXNET_RX_PKT_DEBUG*/
+
+/*=============================================================================
+ *=============================================================================
+ *
+ *                            TX INTERFACE
+ *
+ *=============================================================================
+ *===========================================================================*/
+
+/* tx module context handle */
+typedef void *Vmxnet_TxPkt_h;
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_init
+ *
+ * Desc: Init function for tx packet functionality.
+ *
+ * Params:  (OUT) pkt - private handle.
+ *          (IN) max_frags - max tx ip fragments.
+ *          (IN) has_virt_hdr - device uses virtio header.
+ *
+ * Return:  0 on success, -1 on error
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+int vmxnet_tx_pkt_init(Vmxnet_TxPkt_h *pkt, uint32_t max_frags,
+    bool has_virt_hdr);
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_uninit
+ *
+ * Desc: Clean all tx packet resources.
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  nothing
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+void vmxnet_tx_pkt_uninit(Vmxnet_TxPkt_h pkt);
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_get_vhdr
+ *
+ * Desc: get virtio header.
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  virtio header
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+struct virtio_net_hdr *vmxnet_tx_pkt_get_vhdr(Vmxnet_TxPkt_h pkt);
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_build_vheader
+ *
+ * Desc: build virtio header. (will be stored in module context)
+ *
+ * Params:  (IN) pkt - private handle.
+ *          (IN) tso_enable
+ *          (IN) csum_enable (has to be enabled if tso_enable is true)
+ *          (IN) gso_size - (relevent only if tso enabled)
+ *
+ * Return:  nothing
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+void vmxnet_tx_pkt_build_vheader(Vmxnet_TxPkt_h pkt, bool tso_enable,
+    bool csum_enable, uint32_t gso_size);
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_prepare
+ *
+ * Desc: populates headers and parses them to gether some metadata for later
+ *       use.
+ *
+ * Params:  (IN) pkt - private handle.
+ *          (IN) pa - physical address of tx data
+ *          (IN) len - length of data
+ *
+ * Return:  number of bytes populated by the function.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+size_t vmxnet_tx_pkt_prepare(Vmxnet_TxPkt_h pkt, target_phys_addr_t pa,
+    size_t len);
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_setup_vlan_header
+ *
+ * Desc: updates vlan tag, and adds vlan header in case it is missing.
+ *
+ * Params:  (IN) pkt - private handle.
+ *          (IN) vlan
+ *
+ * Return:  Nothing
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+void vmxnet_tx_pkt_setup_vlan_header(Vmxnet_TxPkt_h pkt, uint16_t vlan);
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_add_fragment
+ *
+ * Desc: populate fragment into pkt context.
+ *
+ * Params:  (IN) pkt - private handle.
+ *          (IN) pa - physical addred of fragment
+ *          (IN) len - length of fragment
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+void vmxnet_tx_pkt_add_fragment(Vmxnet_TxPkt_h pkt, target_phys_addr_t pa,
+    size_t len);
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_update_ip_checksums
+ *
+ * Desc: fix ip header fields and calculate checksums needed.
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  Nothing.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+void vmxnet_tx_pkt_update_ip_checksums(Vmxnet_TxPkt_h pkt);
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_get_total_len
+ *
+ * Desc: Returns the length of all populated data.
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  length of populated data.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+size_t vmxnet_tx_pkt_get_total_len(Vmxnet_TxPkt_h pkt);
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_get_packet_type
+ *
+ * Desc: returns packet type
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  packet type.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+eth_pkt_types_e vmxnet_tx_pkt_get_packet_type(Vmxnet_TxPkt_h pkt);
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_dump
+ *
+ * Desc: Prints packet data if debug is enabled
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  Nothing.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+void vmxnet_tx_pkt_dump(Vmxnet_TxPkt_h pkt);
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_reset
+ *
+ * Desc: reset tx packet private context. (needed to be called between packets)
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  Nothing.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+void vmxnet_tx_pkt_reset(Vmxnet_TxPkt_h pkt);
+
+/******************************************************************************
+ *
+ * Function: vmxnet_tx_pkt_send
+ *
+ * Desc: Send packet to qemu. handles sw offloads if vhdr is not supported.
+ *
+ * Params:  (IN) pkt - private handle.
+ *          (IN) vc - VLANClientState.
+ *
+ * Return:  number of bytes sent.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+size_t vmxnet_tx_pkt_send(Vmxnet_TxPkt_h pkt, VLANClientState *vc);
+
+/*=============================================================================
+ *=============================================================================
+ *
+ *                            RX INTERFACE
+ *
+ *=============================================================================
+ *===========================================================================*/
+
+/* rx module context handle */
+typedef void *Vmxnet_RxPkt_h;
+
+/******************************************************************************
+ *
+ * Function: vmxnet_rx_pkt_uninit
+ *
+ * Desc: Clean all rx packet resources.
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  nothing
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+void vmxnet_rx_pkt_uninit(Vmxnet_RxPkt_h pkt);
+
+/******************************************************************************
+ *
+ * Function: vmxnet_rx_pkt_init
+ *
+ * Desc: Init function for rx packet functionality.
+ *
+ * Params:  (OUT) pkt - private handle.
+ *          (IN) has_virt_hdr - device uses virtio header.
+ *
+ * Return:  0 on success, -1 on error
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+int vmxnet_rx_pkt_init(Vmxnet_RxPkt_h *pkt, bool has_virt_hdr);
+
+/******************************************************************************
+ *
+ * Function: vmxnet_rx_pkt_get_total_len
+ *
+ * Desc: returns total length of data attached to rx context.
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  nothing
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+size_t vmxnet_rx_pkt_get_total_len(Vmxnet_RxPkt_h pkt);
+
+/******************************************************************************
+ *
+ * Function: vmxnet_rx_pkt_get_vhdr
+ *
+ * Desc: returns virtio header stored in rx context.
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  virtio header
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+struct virtio_net_hdr *vmxnet_rx_pkt_get_vhdr(Vmxnet_RxPkt_h pkt);
+
+/******************************************************************************
+ *
+ * Function: vmxnet_rx_pkt_get_packet_type
+ *
+ * Desc: returns packet type.
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  packet type.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+eth_pkt_types_e vmxnet_rx_pkt_get_packet_type(Vmxnet_RxPkt_h pkt);
+
+/******************************************************************************
+ *
+ * Function: vmxnet_rx_pkt_get_vlan_tag
+ *
+ * Desc: returns vlan tag.
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  vlan tag.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+uint16_t vmxnet_rx_pkt_get_vlan_tag(Vmxnet_RxPkt_h pkt);
+
+/******************************************************************************
+ *
+ * Function: vmxnet_rx_pkt_is_vlan_stripped
+ *
+ * Desc: notifies caller if a vlan was stripped from the packet.
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  true if vlan vas stripped form the packet, false otherwize.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+bool vmxnet_rx_pkt_is_vlan_stripped(Vmxnet_RxPkt_h pkt);
+
+/******************************************************************************
+ *
+ * Function: vmxnet_rx_pkt_has_virt_hdr
+ *
+ * Desc: notifies caller if the packet has virtio header
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  true if packet has virtio header, false otherwize.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+bool vmxnet_rx_pkt_has_virt_hdr(Vmxnet_RxPkt_h pkt);
+
+/******************************************************************************
+ *
+ * Function: vmxnet_rx_pkt_get_num_frags
+ *
+ * Desc: returns number of frags attached to the packet.
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  number of frags.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+uint16_t vmxnet_rx_pkt_get_num_frags(Vmxnet_RxPkt_h pkt);
+
+/******************************************************************************
+ *
+ * Function: vmxnet_rx_pkt_attach_data
+ *
+ * Desc: Attach data to rx packet.
+ *
+ * Params:  (IN) pkt - private handle.
+ *          (IN) data
+ *          (IN) len
+ *          (IN) strip_vlan - should the module strip vlan from data.
+ *
+ * Return:  nothing.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+void vmxnet_rx_pkt_attach_data(Vmxnet_RxPkt_h pkt, const void *data,
+    size_t len, bool strip_vlan);
+
+/******************************************************************************
+ *
+ * Function: vmxnet_rx_pkt_get_iovec
+ *
+ * Desc: returns io vector that holds the attached data.
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  iovector.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+struct iovec *vmxnet_rx_pkt_get_iovec(Vmxnet_RxPkt_h pkt);
+
+/******************************************************************************
+ *
+ * Function: vmxnet_rx_pkt_dump
+ *
+ * Desc: prints rx packet data if debug is enabled.
+ *
+ * Params:  (IN) pkt - private handle.
+ *
+ * Return:  Nothing.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+void vmxnet_rx_pkt_dump(Vmxnet_RxPkt_h pkt);
+
+/******************************************************************************
+ *
+ * Function: vmxnet_rx_pkt_set_vhdr
+ *
+ * Desc: copy passed phdr data to packet context.
+ *
+ * Params:  (IN) pkt - private handle.
+ *          (IN) vhdr - new vhdr data.
+ *
+ * Return:  Nothing.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+void vmxnet_rx_pkt_set_vhdr(Vmxnet_RxPkt_h pkt, struct virtio_net_hdr *vhdr);
+
+/******************************************************************************
+ *
+ * Function: vmxnet_rx_pkt_set_packet_type
+ *
+ * Desc: save packet type in packet context
+ *
+ * Params:  (IN) pkt - private handle.
+ *          (IN) packet_type.
+ *
+ * Return:  Nothing.
+ *
+ * Scope: Global
+ *
+ *****************************************************************************/
+void vmxnet_rx_pkt_set_packet_type(Vmxnet_RxPkt_h pkt,
+    eth_pkt_types_e packet_type);
+
+#endif
+
-- 
1.7.7.6