#define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__

  
  #ifdef CONFIG_PROC_FS
  #include <linux/errno.h>
  #include <linux/kernel.h>

  #include <linux/string.h>

  #include <linux/mm.h>
  #include <linux/module.h>
  #include <linux/proc_fs.h>
  #include <linux/time.h>
  #include <linux/seq_file.h>

  #include <linux/uaccess.h>

  #include <linux/atmmpc.h>
  #include <linux/atm.h>

  #include <linux/gfp.h>

  #include "mpc.h"
  #include "mpoa_caches.h"
  
  /*
   * mpoa_proc.c: Implementation MPOA client's proc

   * file system statistics

   */
  
  #if 1

  #define dprintk(format, args...)					\
  	printk(KERN_DEBUG "mpoa:%s: " format, __FILE__, ##args)  /* debug */

  #else

  #define dprintk(format, args...)					\
  	do { if (0)							\
  		printk(KERN_DEBUG "mpoa:%s: " format, __FILE__, ##args);\
  	} while (0)
  #endif
  
  #if 0
  #define ddprintk(format, args...)					\
  	printk(KERN_DEBUG "mpoa:%s: " format, __FILE__, ##args)  /* debug */
  #else
  #define ddprintk(format, args...)					\
  	do { if (0)							\
  		printk(KERN_DEBUG "mpoa:%s: " format, __FILE__, ##args);\
  	} while (0)

  #endif
  
  #define STAT_FILE_NAME "mpc"     /* Our statistic file's name */
  
  extern struct mpoa_client *mpcs;
  extern struct proc_dir_entry *atm_proc_root;  /* from proc.c. */
  
  static int proc_mpc_open(struct inode *inode, struct file *file);
  static ssize_t proc_mpc_write(struct file *file, const char __user *buff,

  			      size_t nbytes, loff_t *ppos);

  
  static int parse_qos(const char *buff);
  
  /*
   *   Define allowed FILE OPERATIONS
   */

  static const struct file_operations mpc_file_operations = {

  	.owner =	THIS_MODULE,
  	.open =		proc_mpc_open,
  	.read =		seq_read,
  	.llseek =	seq_lseek,
  	.write =	proc_mpc_write,
  	.release =	seq_release,
  };
  
  /*
   * Returns the state of an ingress cache entry as a string
   */

  static const char *ingress_state_string(int state)
  {
  	switch (state) {

  	case INGRESS_RESOLVING:

  		return "resolving  ";

  	case INGRESS_RESOLVED:

  		return "resolved   ";

  	case INGRESS_INVALID:

  		return "invalid    ";

  	case INGRESS_REFRESHING:

  		return "refreshing ";

  	}

  
  	return "";

  }
  
  /*
   * Returns the state of an egress cache entry as a string
   */

  static const char *egress_state_string(int state)
  {
  	switch (state) {

  	case EGRESS_RESOLVED:

  		return "resolved   ";

  	case EGRESS_PURGE:

  		return "purge      ";

  	case EGRESS_INVALID:

  		return "invalid    ";

  	}

  
  	return "";

  }
  
  /*
   * FIXME: mpcs (and per-mpc lists) have no locking whatsoever.
   */
  
  static void *mpc_start(struct seq_file *m, loff_t *pos)
  {
  	loff_t l = *pos;
  	struct mpoa_client *mpc;
  
  	if (!l--)
  		return SEQ_START_TOKEN;
  	for (mpc = mpcs; mpc; mpc = mpc->next)
  		if (!l--)
  			return mpc;
  	return NULL;
  }
  
  static void *mpc_next(struct seq_file *m, void *v, loff_t *pos)
  {
  	struct mpoa_client *p = v;
  	(*pos)++;
  	return v == SEQ_START_TOKEN ? mpcs : p->next;
  }
  
  static void mpc_stop(struct seq_file *m, void *v)
  {
  }
  
  /*
   * READING function - called when the /proc/atm/mpoa file is read from.
   */
  static int mpc_show(struct seq_file *m, void *v)
  {
  	struct mpoa_client *mpc = v;

  	int i;
  	in_cache_entry *in_entry;
  	eg_cache_entry *eg_entry;
  	struct timeval now;
  	unsigned char ip_string[16];
  
  	if (v == SEQ_START_TOKEN) {
  		atm_mpoa_disp_qos(m);
  		return 0;
  	}

  	seq_printf(m, "
  Interface %d:
  
  ", mpc->dev_num);

  	seq_printf(m, "Ingress Entries:
  IP address      State      Holding time  Packets fwded  VPI  VCI
  ");
  	do_gettimeofday(&now);
  
  	for (in_entry = mpc->in_cache; in_entry; in_entry = in_entry->next) {

  		sprintf(ip_string, "%pI4", &in_entry->ctrl_info.in_dst_ip);

  		seq_printf(m, "%-16s%s%-14lu%-12u",

  			   ip_string,
  			   ingress_state_string(in_entry->entry_state),
  			   in_entry->ctrl_info.holding_time -
  			   (now.tv_sec-in_entry->tv.tv_sec),
  			   in_entry->packets_fwded);

  		if (in_entry->shortcut)

  			seq_printf(m, "   %-3d  %-3d",
  				   in_entry->shortcut->vpi,
  				   in_entry->shortcut->vci);

  		seq_printf(m, "
  ");
  	}
  
  	seq_printf(m, "
  ");
  	seq_printf(m, "Egress Entries:
  Ingress MPC ATM addr
  Cache-id        State      Holding time  Packets recvd  Latest IP addr   VPI VCI
  ");
  	for (eg_entry = mpc->eg_cache; eg_entry; eg_entry = eg_entry->next) {
  		unsigned char *p = eg_entry->ctrl_info.in_MPC_data_ATM_addr;

  		for (i = 0; i < ATM_ESA_LEN; i++)

  			seq_printf(m, "%02x", p[i]);
  		seq_printf(m, "
  %-16lu%s%-14lu%-15u",
  			   (unsigned long)ntohl(eg_entry->ctrl_info.cache_id),
  			   egress_state_string(eg_entry->entry_state),

  			   (eg_entry->ctrl_info.holding_time -
  			    (now.tv_sec-eg_entry->tv.tv_sec)),

  			   eg_entry->packets_rcvd);

  		/* latest IP address */

  		sprintf(ip_string, "%pI4", &eg_entry->latest_ip_addr);

  		seq_printf(m, "%-16s", ip_string);
  
  		if (eg_entry->shortcut)

  			seq_printf(m, " %-3d %-3d",
  				   eg_entry->shortcut->vpi,
  				   eg_entry->shortcut->vci);

  		seq_printf(m, "
  ");
  	}
  	seq_printf(m, "
  ");
  	return 0;
  }

  static const struct seq_operations mpc_op = {

  	.start =	mpc_start,
  	.next =		mpc_next,
  	.stop =		mpc_stop,
  	.show =		mpc_show
  };
  
  static int proc_mpc_open(struct inode *inode, struct file *file)
  {
  	return seq_open(file, &mpc_op);
  }
  
  static ssize_t proc_mpc_write(struct file *file, const char __user *buff,

  			      size_t nbytes, loff_t *ppos)

  {

  	char *page, *p;

  	unsigned len;

  	if (nbytes == 0)

  		return 0;

  	if (nbytes >= PAGE_SIZE)

  		nbytes = PAGE_SIZE-1;

  	page = (char *)__get_free_page(GFP_KERNEL);
  	if (!page)

  		return -ENOMEM;

  	for (p = page, len = 0; len < nbytes; p++, len++) {
  		if (get_user(*p, buff++)) {

  			free_page((unsigned long)page);
  			return -EFAULT;
  		}

  		if (*p == '\0' || *p == '
  ')
  			break;
  	}

  	*p = '\0';

  
  	if (!parse_qos(page))

  		printk("mpoa: proc_mpc_write: could not parse '%s'
  ", page);
  
  	free_page((unsigned long)page);

  	return len;

  }
  
  static int parse_qos(const char *buff)
  {

  	/* possible lines look like this
  	 * add 130.230.54.142 tx=max_pcr,max_sdu rx=max_pcr,max_sdu
  	 */
  	unsigned char ip[4];

  	int tx_pcr, tx_sdu, rx_pcr, rx_sdu;

  	__be32 ipaddr;
  	struct atm_qos qos;
  
  	memset(&qos, 0, sizeof(struct atm_qos));

  
  	if (sscanf(buff, "del %hhu.%hhu.%hhu.%hhu",
  			ip, ip+1, ip+2, ip+3) == 4) {

  		ipaddr = *(__be32 *)ip;

  		return atm_mpoa_delete_qos(atm_mpoa_search_qos(ipaddr));
  	}
  
  	if (sscanf(buff, "add %hhu.%hhu.%hhu.%hhu tx=%d,%d rx=tx",
  			ip, ip+1, ip+2, ip+3, &tx_pcr, &tx_sdu) == 6) {
  		rx_pcr = tx_pcr;
  		rx_sdu = tx_sdu;
  	} else if (sscanf(buff, "add %hhu.%hhu.%hhu.%hhu tx=%d,%d rx=%d,%d",
  		ip, ip+1, ip+2, ip+3, &tx_pcr, &tx_sdu, &rx_pcr, &rx_sdu) != 8)
  		return 0;

  	ipaddr = *(__be32 *)ip;

  	qos.txtp.traffic_class = ATM_CBR;
  	qos.txtp.max_pcr = tx_pcr;
  	qos.txtp.max_sdu = tx_sdu;
  	qos.rxtp.traffic_class = ATM_CBR;
  	qos.rxtp.max_pcr = rx_pcr;
  	qos.rxtp.max_sdu = rx_sdu;

  	qos.aal = ATM_AAL5;

  	dprintk("parse_qos(): setting qos paramameters to tx=%d,%d rx=%d,%d
  ",
  		qos.txtp.max_pcr, qos.txtp.max_sdu,
  		qos.rxtp.max_pcr, qos.rxtp.max_sdu);

  
  	atm_mpoa_add_qos(ipaddr, &qos);
  	return 1;
  }
  
  /*
   * INITIALIZATION function - called when module is initialized/loaded.
   */
  int mpc_proc_init(void)
  {
  	struct proc_dir_entry *p;

  	p = proc_create(STAT_FILE_NAME, 0, atm_proc_root, &mpc_file_operations);

  	if (!p) {

  		pr_err("Unable to initialize /proc/atm/%s
  ", STAT_FILE_NAME);

  		return -ENOMEM;
  	}

  	return 0;
  }
  
  /*
   * DELETING function - called when module is removed.
   */
  void mpc_proc_clean(void)
  {

  	remove_proc_entry(STAT_FILE_NAME, atm_proc_root);

  }

  #endif /* CONFIG_PROC_FS */