/* 
 * This file is part of the Palacios Virtual Machine Monitor developed
 * by the V3VEE Project with funding from the United States National 
 * Science Foundation and the Department of Energy.  
 *
 * The V3VEE Project is a joint project between Northwestern University
 * and the University of New Mexico.  You can find out more at 
 * http://www.v3vee.org
 *
 * Copyright (c) 2008, Lei Xia <lxia@northwestern.edu>
 * Copyright (c) 2008, The V3VEE Project <http://www.v3vee.org> 
 * All rights reserved.
 *
 * Author: Lei Xia <lxia@northwestern.edu>
 * 		 
 *
 * This is free software.  You are permitted to use,
 * redistribute, and modify it as specified in the file "V3VEE_LICENSE".
 */
//backend device for Virtio NIC

#include <palacios/vmm_vnet.h>
#include <palacios/vmm.h>
#include <palacios/vmm_dev_mgr.h>
#include <devices/lnx_virtio_pci.h>
#include <palacios/vm_guest_mem.h>
#include <devices/pci.h>
#include <palacios/vmm_sprintf.h>

#ifndef CONFIG_DEBUG_VNET_NIC
#undef PrintDebug
#define PrintDebug(fmt, args...)
#endif


struct vnet_nic_state {
    char mac[6];
    struct guest_info * core;
    struct v3_dev_net_ops net_ops;
};

//used when virtio_nic get a packet from guest and send it to the backend
static int vnet_send(uint8_t * buf, uint32_t len, void * private_data, struct vm_device *dest_dev){
    struct v3_vnet_pkt * pkt = NULL;

    PrintDebug("Virtio VNET-NIC: send pkt size: %d\n", len);
#ifdef CONFIG_DEBUG_VNET_NIC
    v3_hexdump(buf, len, NULL, 0);
#endif

    pkt = (struct v3_vnet_pkt *)V3_Malloc(sizeof(struct v3_vnet_pkt));

    if(pkt == NULL){
	PrintError("Malloc() fails");
	return -1;
    }

    pkt->size = len;
    memcpy(pkt->data, buf, pkt->size);

    v3_vnet_send_pkt(pkt);

    V3_Free(pkt);
    return 0;
}


// We need to make this dynamically allocated
//static struct v3_dev_net_ops net_ops = {
//    .send = vnet_send, 
//};

static int virtio_input(struct v3_vm_info *info, struct v3_vnet_pkt * pkt, void * private_data){
    struct vnet_nic_state *vnetnic = (struct vnet_nic_state *)private_data;
	
    PrintDebug("Vnet-nic: In input: vnet_nic state %p\n", vnetnic);	

    return vnetnic->net_ops.recv(pkt->data, pkt->size, vnetnic->net_ops.frontend_data);
}

#if 0
static int sendto_buf(struct vnet_nic_dev_state *vnetnic_dev, uchar_t * buf, uint_t size) {
    struct eth_pkt *pkt;

    pkt = (struct eth_pkt *)V3_Malloc(sizeof(struct eth_pkt));
    if(pkt == NULL){
        PrintError("Vnet NIC: Memory allocate fails\n");
        return -1;
    }
  
    pkt->size = size;
    memcpy(pkt->data, buf, size);
    v3_enqueue(vnetnic_dev->inpkt_q, (addr_t)pkt);
	
    PrintDebug("Vnet NIC: sendto_buf: packet: (size:%d)\n", (int)pkt->size);

    return pkt->size;
}

/*
  *called in svm/vmx handler
  *iteative handled the unsent packet in incoming packet queues for
  *all virtio nic devices in this guest
  */
int v3_virtionic_pktprocess(struct guest_info * info)
{
    struct eth_pkt *pkt = NULL;
    struct virtio_net_state *net_state;
    int i;

    //PrintDebug("Virtio NIC: processing guest %p\n", info);
    for (i = 0; i < net_idx; i++) {
        while (1) {
            net_state = temp_net_states[i];
            if(net_state->dev->vm != info)
                break;

            pkt = (struct eth_pkt *)v3_dequeue(net_state->inpkt_q);
            if(pkt == NULL) 
                break;
			
            if (send_pkt_to_guest(net_state, pkt->data, pkt->size, 1, NULL)) {
                PrintDebug("Virtio NIC: %p In pkt_handle: send one packet! pt length %d\n", 
				net_state, (int)pkt->size);  
            } else {
                PrintDebug("Virtio NIC: %p In pkt_handle: Fail to send one packet, pt length %d, discard it!\n", 
				net_state, (int)pkt->size); 
            }
	
            V3_Free(pkt);
        }
    }
    
    return 0;
}


/*
  *called in svm/vmx handler
  *iteative handled the unsent packet in incoming packet queues for
  *all virtio nic devices in this guest
  */
int v3_vnetnic_pktprocess(struct guest_info * info)
{
 
    return 0;
}

#endif

//register a virtio device to the vnet as backend
int register_to_vnet(struct v3_vm_info * vm,
		     struct vnet_nic_state *vnet_nic,
		     char *dev_name,
		     uchar_t mac[6]) { 
   
    PrintDebug("Vnet-nic: register Vnet-nic device %s, state %p to VNET\n", dev_name, vnet_nic);
	
    v3_vnet_add_dev(vm, mac, virtio_input, (void *)vnet_nic);

    return 0;
}

static int vnet_nic_free(struct vm_device * dev) {
    return 0;
}

static struct v3_device_ops dev_ops = {
    .free = vnet_nic_free,
    .reset = NULL,
    .start = NULL,
    .stop = NULL,
};

static int vnet_nic_init(struct v3_vm_info * vm, v3_cfg_tree_t * cfg) {
    struct vnet_nic_state * vnetnic = NULL;
    char * name = v3_cfg_val(cfg, "name");

    v3_cfg_tree_t * frontend_cfg = v3_cfg_subtree(cfg, "frontend");

    vnetnic = (struct vnet_nic_state *)V3_Malloc(sizeof(struct vnet_nic_state));
    memset(vnetnic, 0, sizeof(struct vnet_nic_state));

    struct vm_device * dev = v3_allocate_device(name, &dev_ops, vnetnic);

    if (v3_attach_device(vm, dev) == -1) {
	PrintError("Could not attach device %s\n", name);
	return -1;
    }

    vnetnic->net_ops.send = vnet_send;
    if (v3_dev_connect_net(vm, v3_cfg_val(frontend_cfg, "tag"), 
			   &(vnetnic->net_ops), frontend_cfg, vnetnic) == -1) {
	PrintError("Could not connect %s to frontend %s\n", 
		   name, v3_cfg_val(frontend_cfg, "tag"));
	return -1;
    }

    if (register_to_vnet(vm, vnetnic, name, vnetnic->mac) == -1) {
	return -1;
    }

    PrintDebug("Vnet-nic device %s initialized\n", name);

    return 0;
}

device_register("VNET_NIC", vnet_nic_init)