/*****************************************************************************
* wanproc.c     WAN Router Module. /proc filesystem interface.
*
*               This module is completely hardware-independent and provides
*               access to the router using Linux /proc filesystem.
*
* Author:       Gideon Hack
*
* Copyright:    (c) 1995-1999 Sangoma Technologies Inc.
*
*               This program is free software; you can redistribute it and/or
*               modify it under the terms of the GNU General Public License
*               as published by the Free Software Foundation; either version
*               2 of the License, or (at your option) any later version.
* ============================================================================
* Jun 02, 1999  Gideon Hack     Updates for Linux 2.2.X kernels.
* Jun 29, 1997  Alan Cox        Merged with 1.0.3 vendor code
* Jan 29, 1997  Gene Kozin      v1.0.1. Implemented /proc read routines
* Jan 30, 1997  Alan Cox        Hacked around for 2.1
* Dec 13, 1996  Gene Kozin      Initial version (based on Sangoma's WANPIPE)
*****************************************************************************/

#include <linux/init.h>         /* __initfunc et al. */
#include <linux/stddef.h>       /* offsetof(), etc. */
#include <linux/errno.h>        /* return codes */
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/wanrouter.h>    /* WAN router API definitions */
#include <linux/seq_file.h>
#include <linux/mutex.h>

#include <net/net_namespace.h>
#include <asm/io.h>

#define PROC_STATS_FORMAT "%30s: %12lu\n"

/****** Defines and Macros **************************************************/

#define PROT_DECODE(prot) ((prot == WANCONFIG_FR) ? " FR" :\
                              (prot == WANCONFIG_X25) ? " X25" : \
                                 (prot == WANCONFIG_PPP) ? " PPP" : \
                                    (prot == WANCONFIG_CHDLC) ? " CHDLC": \
                                       (prot == WANCONFIG_MPPP) ? " MPPP" : \
                                           " Unknown" )

/****** Function Prototypes *************************************************/

#ifdef CONFIG_PROC_FS

/* Miscellaneous */

/*
 *      Structures for interfacing with the /proc filesystem.
 *      Router creates its own directory /proc/net/router with the following
 *      entries:
 *      config          device configuration
 *      status          global device statistics
 *      <device>        entry for each WAN device
 */

/*
 *      Generic /proc/net/router/<file> file and inode operations
 */

/*
 *      /proc/net/router
 */

static DEFINE_MUTEX(config_mutex);
static struct proc_dir_entry *proc_router;

/* Strings */

/*
 *      Interface functions
 */

/****** Proc filesystem entry points ****************************************/

/*
 *      Iterator
 */
static void *r_start(struct seq_file *m, loff_t *pos)
        __acquires(kernel_lock)
{
        struct wan_device *wandev;
        loff_t l = *pos;

        mutex_lock(&config_mutex);
        if (!l--)
                return SEQ_START_TOKEN;
        for (wandev = wanrouter_router_devlist; l-- && wandev;
             wandev = wandev->next)
                ;
        return wandev;
}

static void *r_next(struct seq_file *m, void *v, loff_t *pos)
{
        struct wan_device *wandev = v;
        (*pos)++;
        return (v == SEQ_START_TOKEN) ? wanrouter_router_devlist : wandev->next;
}

static void r_stop(struct seq_file *m, void *v)
        __releases(kernel_lock)
{
        mutex_unlock(&config_mutex);
}

static int config_show(struct seq_file *m, void *v)
{
        struct wan_device *p = v;
        if (v == SEQ_START_TOKEN) {
                seq_puts(m, "Device name    | port |IRQ|DMA|  mem.addr  |"
                            "mem.size|option1|option2|option3|option4\n");
                return 0;
        }
        if (!p->state)
                return 0;
        seq_printf(m, "%-15s|0x%-4X|%3u|%3u| 0x%-8lX |0x%-6X|%7u|%7u|%7u|%7u\n",
                        p->name, p->ioport, p->irq, p->dma, p->maddr, p->msize,
                        p->hw_opt[0], p->hw_opt[1], p->hw_opt[2], p->hw_opt[3]);
        return 0;
}

static int status_show(struct seq_file *m, void *v)
{
        struct wan_device *p = v;
        if (v == SEQ_START_TOKEN) {
                seq_puts(m, "Device name    |protocol|station|interface|"
                            "clocking|baud rate| MTU |ndev|link state\n");
                return 0;
        }
        if (!p->state)
                return 0;
        seq_printf(m, "%-15s|%-8s| %-7s| %-9s|%-8s|%9u|%5u|%3u |",
                p->name,
                PROT_DECODE(p->config_id),
                p->config_id == WANCONFIG_FR ?
                        (p->station ? "Node" : "CPE") :
                        (p->config_id == WANCONFIG_X25 ?
                        (p->station ? "DCE" : "DTE") :
                        ("N/A")),
                p->interface ? "V.35" : "RS-232",
                p->clocking ? "internal" : "external",
                p->bps,
                p->mtu,
                p->ndev);

        switch (p->state) {
        case WAN_UNCONFIGURED:
                seq_printf(m, "%-12s\n", "unconfigured");
                break;
        case WAN_DISCONNECTED:
                seq_printf(m, "%-12s\n", "disconnected");
                break;
        case WAN_CONNECTING:
                seq_printf(m, "%-12s\n", "connecting");
                break;
        case WAN_CONNECTED:
                seq_printf(m, "%-12s\n", "connected");
                break;
        default:
                seq_printf(m, "%-12s\n", "invalid");
                break;
        }
        return 0;
}

static const struct seq_operations config_op = {
        .start  = r_start,
        .next   = r_next,
        .stop   = r_stop,
        .show   = config_show,
};

static const struct seq_operations status_op = {
        .start  = r_start,
        .next   = r_next,
        .stop   = r_stop,
        .show   = status_show,
};

static int config_open(struct inode *inode, struct file *file)
{
        return seq_open(file, &config_op);
}

static int status_open(struct inode *inode, struct file *file)
{
        return seq_open(file, &status_op);
}

static const struct file_operations config_fops = {
        .owner   = THIS_MODULE,
        .open    = config_open,
        .read    = seq_read,
        .llseek  = seq_lseek,
        .release = seq_release,
};

static const struct file_operations status_fops = {
        .owner   = THIS_MODULE,
        .open    = status_open,
        .read    = seq_read,
        .llseek  = seq_lseek,
        .release = seq_release,
};

static int wandev_show(struct seq_file *m, void *v)
{
        struct wan_device *wandev = m->private;

        if (wandev->magic != ROUTER_MAGIC)
                return 0;

        if (!wandev->state) {
                seq_puts(m, "device is not configured!\n");
                return 0;
        }

        /* Update device statistics */
        if (wandev->update) {
                int err = wandev->update(wandev);
                if (err == -EAGAIN) {
                        seq_puts(m, "Device is busy!\n");
                        return 0;
                }
                if (err) {
                        seq_puts(m, "Device is not configured!\n");
                        return 0;
                }
        }

        seq_printf(m, PROC_STATS_FORMAT,
                "total packets received", wandev->stats.rx_packets);
        seq_printf(m, PROC_STATS_FORMAT,
                "total packets transmitted", wandev->stats.tx_packets);
        seq_printf(m, PROC_STATS_FORMAT,
                "total bytes received", wandev->stats.rx_bytes);
        seq_printf(m, PROC_STATS_FORMAT,
                "total bytes transmitted", wandev->stats.tx_bytes);
        seq_printf(m, PROC_STATS_FORMAT,
                "bad packets received", wandev->stats.rx_errors);
        seq_printf(m, PROC_STATS_FORMAT,
                "packet transmit problems", wandev->stats.tx_errors);
        seq_printf(m, PROC_STATS_FORMAT,
                "received frames dropped", wandev->stats.rx_dropped);
        seq_printf(m, PROC_STATS_FORMAT,
                "transmit frames dropped", wandev->stats.tx_dropped);
        seq_printf(m, PROC_STATS_FORMAT,
                "multicast packets received", wandev->stats.multicast);
        seq_printf(m, PROC_STATS_FORMAT,
                "transmit collisions", wandev->stats.collisions);
        seq_printf(m, PROC_STATS_FORMAT,
                "receive length errors", wandev->stats.rx_length_errors);
        seq_printf(m, PROC_STATS_FORMAT,
                "receiver overrun errors", wandev->stats.rx_over_errors);
        seq_printf(m, PROC_STATS_FORMAT,
                "CRC errors", wandev->stats.rx_crc_errors);
        seq_printf(m, PROC_STATS_FORMAT,
                "frame format errors (aborts)", wandev->stats.rx_frame_errors);
        seq_printf(m, PROC_STATS_FORMAT,
                "receiver fifo overrun", wandev->stats.rx_fifo_errors);
        seq_printf(m, PROC_STATS_FORMAT,
                "receiver missed packet", wandev->stats.rx_missed_errors);
        seq_printf(m, PROC_STATS_FORMAT,
                "aborted frames transmitted", wandev->stats.tx_aborted_errors);
        return 0;
}

static int wandev_open(struct inode *inode, struct file *file)
{
        return single_open(file, wandev_show, PDE(inode)->data);
}

static const struct file_operations wandev_fops = {
        .owner   = THIS_MODULE,
        .open    = wandev_open,
        .read    = seq_read,
        .llseek  = seq_lseek,
        .release = single_release,
        .unlocked_ioctl  = wanrouter_ioctl,
};

/*
 *      Initialize router proc interface.
 */

int __init wanrouter_proc_init(void)
{
        struct proc_dir_entry *p;
        proc_router = proc_mkdir(ROUTER_NAME, init_net.proc_net);
        if (!proc_router)
                goto fail;

        p = proc_create("config", S_IRUGO, proc_router, &config_fops);
        if (!p)
                goto fail_config;
        p = proc_create("status", S_IRUGO, proc_router, &status_fops);
        if (!p)
                goto fail_stat;
        return 0;
fail_stat:
        remove_proc_entry("config", proc_router);
fail_config:
        remove_proc_entry(ROUTER_NAME, init_net.proc_net);
fail:
        return -ENOMEM;
}

/*
 *      Clean up router proc interface.
 */

void wanrouter_proc_cleanup(void)
{
        remove_proc_entry("config", proc_router);
        remove_proc_entry("status", proc_router);
        remove_proc_entry(ROUTER_NAME, init_net.proc_net);
}

/*
 *      Add directory entry for WAN device.
 */

int wanrouter_proc_add(struct wan_device* wandev)
{
        if (wandev->magic != ROUTER_MAGIC)
                return -EINVAL;

        wandev->dent = proc_create(wandev->name, S_IRUGO,
                                   proc_router, &wandev_fops);
        if (!wandev->dent)
                return -ENOMEM;
        wandev->dent->data      = wandev;
        return 0;
}

/*
 *      Delete directory entry for WAN device.
 */
int wanrouter_proc_delete(struct wan_device* wandev)
{
        if (wandev->magic != ROUTER_MAGIC)
                return -EINVAL;
        remove_proc_entry(wandev->name, proc_router);
        return 0;
}

#else

/*
 *      No /proc - output stubs
 */

int __init wanrouter_proc_init(void)
{
        return 0;
}

void wanrouter_proc_cleanup(void)
{
}

int wanrouter_proc_add(struct wan_device *wandev)
{
        return 0;
}

int wanrouter_proc_delete(struct wan_device *wandev)
{
        return 0;
}

#endif

/*
 *      End
 */