/* net/atm/proc.c - ATM /proc interface
   *
   * Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA
   *
   * seq_file api usage by romieu@fr.zoreil.com
   *
   * Evaluating the efficiency of the whole thing if left as an exercise to
   * the reader.
   */

  #include <linux/module.h> /* for EXPORT_SYMBOL */
  #include <linux/string.h>
  #include <linux/types.h>
  #include <linux/mm.h>
  #include <linux/fs.h>
  #include <linux/stat.h>
  #include <linux/proc_fs.h>
  #include <linux/seq_file.h>
  #include <linux/errno.h>
  #include <linux/atm.h>
  #include <linux/atmdev.h>
  #include <linux/netdevice.h>
  #include <linux/atmclip.h>
  #include <linux/init.h> /* for __init */

  #include <linux/slab.h>

  #include <net/net_namespace.h>

  #include <net/atmclip.h>

  #include <linux/uaccess.h>
  #include <linux/param.h> /* for HZ */

  #include <linux/atomic.h>

  #include "resources.h"
  #include "common.h" /* atm_proc_init prototype */
  #include "signaling.h" /* to get sigd - ugly too */

  static ssize_t proc_dev_atm_read(struct file *file, char __user *buf,
  				 size_t count, loff_t *pos);

  static const struct file_operations proc_atm_dev_ops = {

  	.owner =	THIS_MODULE,
  	.read =		proc_dev_atm_read,

  	.llseek =	noop_llseek,

  };
  
  static void add_stats(struct seq_file *seq, const char *aal,
    const struct k_atm_aal_stats *stats)
  {
  	seq_printf(seq, "%s ( %d %d %d %d %d )", aal,

  		   atomic_read(&stats->tx), atomic_read(&stats->tx_err),
  		   atomic_read(&stats->rx), atomic_read(&stats->rx_err),
  		   atomic_read(&stats->rx_drop));

  }
  
  static void atm_dev_info(struct seq_file *seq, const struct atm_dev *dev)
  {
  	int i;
  
  	seq_printf(seq, "%3d %-8s", dev->number, dev->type);
  	for (i = 0; i < ESI_LEN; i++)
  		seq_printf(seq, "%02x", dev->esi[i]);
  	seq_puts(seq, "  ");
  	add_stats(seq, "0", &dev->stats.aal0);
  	seq_puts(seq, "  ");
  	add_stats(seq, "5", &dev->stats.aal5);
  	seq_printf(seq, "\t[%d]", atomic_read(&dev->refcnt));
  	seq_putc(seq, '
  ');
  }
  
  struct vcc_state {
  	int bucket;
  	struct sock *sk;
  	int family;
  };
  
  static inline int compare_family(struct sock *sk, int family)
  {
  	return !family || (sk->sk_family == family);
  }
  
  static int __vcc_walk(struct sock **sock, int family, int *bucket, loff_t l)
  {
  	struct sock *sk = *sock;

  	if (sk == SEQ_START_TOKEN) {

  		for (*bucket = 0; *bucket < VCC_HTABLE_SIZE; ++*bucket) {
  			struct hlist_head *head = &vcc_hash[*bucket];
  
  			sk = hlist_empty(head) ? NULL : __sk_head(head);
  			if (sk)
  				break;
  		}
  		l--;

  	}

  try_again:
  	for (; sk; sk = sk_next(sk)) {
  		l -= compare_family(sk, family);
  		if (l < 0)
  			goto out;
  	}
  	if (!sk && ++*bucket < VCC_HTABLE_SIZE) {
  		sk = sk_head(&vcc_hash[*bucket]);
  		goto try_again;
  	}

  	sk = SEQ_START_TOKEN;

  out:
  	*sock = sk;
  	return (l < 0);
  }
  
  static inline void *vcc_walk(struct vcc_state *state, loff_t l)
  {
  	return __vcc_walk(&state->sk, state->family, &state->bucket, l) ?
  	       state : NULL;
  }
  
  static int __vcc_seq_open(struct inode *inode, struct file *file,

  	int family, const struct seq_operations *ops)

  {
  	struct vcc_state *state;

  	state = __seq_open_private(file, ops, sizeof(*state));
  	if (state == NULL)
  		return -ENOMEM;

  
  	state->family = family;

  	return 0;

  }
  
  static void *vcc_seq_start(struct seq_file *seq, loff_t *pos)

  	__acquires(vcc_sklist_lock)

  {
  	struct vcc_state *state = seq->private;
  	loff_t left = *pos;
  
  	read_lock(&vcc_sklist_lock);

  	state->sk = SEQ_START_TOKEN;
  	return left ? vcc_walk(state, left) : SEQ_START_TOKEN;

  }
  
  static void vcc_seq_stop(struct seq_file *seq, void *v)

  	__releases(vcc_sklist_lock)

  {
  	read_unlock(&vcc_sklist_lock);
  }
  
  static void *vcc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
  {
  	struct vcc_state *state = seq->private;
  
  	v = vcc_walk(state, 1);
  	*pos += !!PTR_ERR(v);
  	return v;
  }
  
  static void pvc_info(struct seq_file *seq, struct atm_vcc *vcc)
  {

  	static const char *const class_name[] = {
  		"off", "UBR", "CBR", "VBR", "ABR"};

  	static const char *const aal_name[] = {

  		"---",	"1",	"2",	"3/4",	/*  0- 3 */
  		"???",	"5",	"???",	"???",	/*  4- 7 */
  		"???",	"???",	"???",	"???",	/*  8-11 */
  		"???",	"0",	"???",	"???"};	/* 12-15 */
  
  	seq_printf(seq, "%3d %3d %5d %-3s %7d %-5s %7d %-6s",

  		   vcc->dev->number, vcc->vpi, vcc->vci,
  		   vcc->qos.aal >= ARRAY_SIZE(aal_name) ? "err" :
  		   aal_name[vcc->qos.aal], vcc->qos.rxtp.min_pcr,
  		   class_name[vcc->qos.rxtp.traffic_class],
  		   vcc->qos.txtp.min_pcr,
  		   class_name[vcc->qos.txtp.traffic_class]);

  	if (test_bit(ATM_VF_IS_CLIP, &vcc->flags)) {
  		struct clip_vcc *clip_vcc = CLIP_VCC(vcc);
  		struct net_device *dev;
  
  		dev = clip_vcc->entry ? clip_vcc->entry->neigh->dev : NULL;
  		seq_printf(seq, "CLIP, Itf:%s, Encap:",
  		    dev ? dev->name : "none?");
  		seq_printf(seq, "%s", clip_vcc->encap ? "LLC/SNAP" : "None");
  	}
  	seq_putc(seq, '
  ');
  }
  
  static const char *vcc_state(struct atm_vcc *vcc)
  {

  	static const char *const map[] = { ATM_VS2TXT_MAP };

  
  	return map[ATM_VF2VS(vcc->flags)];
  }
  
  static void vcc_info(struct seq_file *seq, struct atm_vcc *vcc)
  {
  	struct sock *sk = sk_atm(vcc);

  	seq_printf(seq, "%pK ", vcc);

  	if (!vcc->dev)
  		seq_printf(seq, "Unassigned    ");

  	else

  		seq_printf(seq, "%3d %3d %5d ", vcc->dev->number, vcc->vpi,
  			vcc->vci);
  	switch (sk->sk_family) {

  	case AF_ATMPVC:
  		seq_printf(seq, "PVC");
  		break;
  	case AF_ATMSVC:
  		seq_printf(seq, "SVC");
  		break;
  	default:
  		seq_printf(seq, "%3d", sk->sk_family);

  	}

  	seq_printf(seq, " %04lx  %5d %7d/%7d %7d/%7d [%d]
  ",
  		   vcc->flags, sk->sk_err,
  		   sk_wmem_alloc_get(sk), sk->sk_sndbuf,
  		   sk_rmem_alloc_get(sk), sk->sk_rcvbuf,
  		   atomic_read(&sk->sk_refcnt));

  }
  
  static void svc_info(struct seq_file *seq, struct atm_vcc *vcc)
  {
  	if (!vcc->dev)
  		seq_printf(seq, sizeof(void *) == 4 ?

  			   "N/A@%pK%10s" : "N/A@%pK%2s", vcc, "");

  	else
  		seq_printf(seq, "%3d %3d %5d         ",
  			   vcc->dev->number, vcc->vpi, vcc->vci);
  	seq_printf(seq, "%-10s ", vcc_state(vcc));
  	seq_printf(seq, "%s%s", vcc->remote.sas_addr.pub,
  	    *vcc->remote.sas_addr.pub && *vcc->remote.sas_addr.prv ? "+" : "");
  	if (*vcc->remote.sas_addr.prv) {
  		int i;
  
  		for (i = 0; i < ATM_ESA_LEN; i++)
  			seq_printf(seq, "%02x", vcc->remote.sas_addr.prv[i]);
  	}
  	seq_putc(seq, '
  ');
  }
  
  static int atm_dev_seq_show(struct seq_file *seq, void *v)
  {
  	static char atm_dev_banner[] =
  		"Itf Type    ESI/\"MAC\"addr "
  		"AAL(TX,err,RX,err,drop) ...               [refcnt]
  ";

  	if (v == &atm_devs)

  		seq_puts(seq, atm_dev_banner);
  	else {
  		struct atm_dev *dev = list_entry(v, struct atm_dev, dev_list);
  
  		atm_dev_info(seq, dev);
  	}

  	return 0;

  }

  static const struct seq_operations atm_dev_seq_ops = {

  	.start	= atm_dev_seq_start,
  	.next	= atm_dev_seq_next,
  	.stop	= atm_dev_seq_stop,
  	.show	= atm_dev_seq_show,
  };

  static int atm_dev_seq_open(struct inode *inode, struct file *file)
  {
  	return seq_open(file, &atm_dev_seq_ops);
  }

  static const struct file_operations devices_seq_fops = {

  	.open		= atm_dev_seq_open,
  	.read		= seq_read,
  	.llseek		= seq_lseek,
  	.release	= seq_release,
  };
  
  static int pvc_seq_show(struct seq_file *seq, void *v)
  {

  	static char atm_pvc_banner[] =

  		"Itf VPI VCI   AAL RX(PCR,Class) TX(PCR,Class)
  ";

  	if (v == SEQ_START_TOKEN)

  		seq_puts(seq, atm_pvc_banner);
  	else {
  		struct vcc_state *state = seq->private;
  		struct atm_vcc *vcc = atm_sk(state->sk);
  
  		pvc_info(seq, vcc);
  	}
  	return 0;
  }

  static const struct seq_operations pvc_seq_ops = {

  	.start	= vcc_seq_start,
  	.next	= vcc_seq_next,
  	.stop	= vcc_seq_stop,
  	.show	= pvc_seq_show,
  };
  
  static int pvc_seq_open(struct inode *inode, struct file *file)
  {
  	return __vcc_seq_open(inode, file, PF_ATMPVC, &pvc_seq_ops);
  }

  static const struct file_operations pvc_seq_fops = {

  	.open		= pvc_seq_open,
  	.read		= seq_read,
  	.llseek		= seq_lseek,

  	.release	= seq_release_private,

  };
  
  static int vcc_seq_show(struct seq_file *seq, void *v)
  {

  	if (v == SEQ_START_TOKEN) {

  		seq_printf(seq, sizeof(void *) == 4 ? "%-8s%s" : "%-16s%s",
  			"Address ", "Itf VPI VCI   Fam Flags Reply "
  			"Send buffer     Recv buffer      [refcnt]
  ");
  	} else {
  		struct vcc_state *state = seq->private;
  		struct atm_vcc *vcc = atm_sk(state->sk);
  
  		vcc_info(seq, vcc);
  	}
  	return 0;

  }

  static const struct seq_operations vcc_seq_ops = {

  	.start	= vcc_seq_start,
  	.next	= vcc_seq_next,
  	.stop	= vcc_seq_stop,
  	.show	= vcc_seq_show,

  };

  static int vcc_seq_open(struct inode *inode, struct file *file)
  {

  	return __vcc_seq_open(inode, file, 0, &vcc_seq_ops);

  }

  static const struct file_operations vcc_seq_fops = {

  	.open		= vcc_seq_open,
  	.read		= seq_read,
  	.llseek		= seq_lseek,

  	.release	= seq_release_private,

  };
  
  static int svc_seq_show(struct seq_file *seq, void *v)
  {

  	static const char atm_svc_banner[] =

  		"Itf VPI VCI           State      Remote
  ";

  	if (v == SEQ_START_TOKEN)

  		seq_puts(seq, atm_svc_banner);
  	else {
  		struct vcc_state *state = seq->private;
  		struct atm_vcc *vcc = atm_sk(state->sk);
  
  		svc_info(seq, vcc);
  	}
  	return 0;
  }

  static const struct seq_operations svc_seq_ops = {

  	.start	= vcc_seq_start,
  	.next	= vcc_seq_next,
  	.stop	= vcc_seq_stop,
  	.show	= svc_seq_show,
  };
  
  static int svc_seq_open(struct inode *inode, struct file *file)
  {
  	return __vcc_seq_open(inode, file, PF_ATMSVC, &svc_seq_ops);
  }

  static const struct file_operations svc_seq_fops = {

  	.open		= svc_seq_open,
  	.read		= seq_read,
  	.llseek		= seq_lseek,

  	.release	= seq_release_private,

  };
  
  static ssize_t proc_dev_atm_read(struct file *file, char __user *buf,
  				 size_t count, loff_t *pos)
  {
  	struct atm_dev *dev;
  	unsigned long page;
  	int length;

  	if (count == 0)
  		return 0;

  	page = get_zeroed_page(GFP_KERNEL);

  	if (!page)
  		return -ENOMEM;

  	dev = PDE(file->f_path.dentry->d_inode)->data;

  	if (!dev->ops->proc_read)
  		length = -EINVAL;
  	else {

  		length = dev->ops->proc_read(dev, pos, (char *)page);
  		if (length > count)
  			length = -EINVAL;

  	}
  	if (length >= 0) {

  		if (copy_to_user(buf, (char *)page, length))
  			length = -EFAULT;

  		(*pos)++;
  	}
  	free_page(page);
  	return length;
  }

  struct proc_dir_entry *atm_proc_root;
  EXPORT_SYMBOL(atm_proc_root);
  
  
  int atm_proc_dev_register(struct atm_dev *dev)
  {

  	int error;
  
  	/* No proc info */
  	if (!dev->ops->proc_read)
  		return 0;
  
  	error = -ENOMEM;

  	dev->proc_name = kasprintf(GFP_KERNEL, "%s:%d", dev->type, dev->number);

  	if (!dev->proc_name)
  		goto err_out;

  	dev->proc_entry = proc_create_data(dev->proc_name, 0, atm_proc_root,
  					   &proc_atm_dev_ops, dev);

  	if (!dev->proc_entry)
  		goto err_free_name;

  	return 0;

  err_free_name:
  	kfree(dev->proc_name);
  err_out:
  	return error;
  }

  void atm_proc_dev_deregister(struct atm_dev *dev)
  {
  	if (!dev->ops->proc_read)
  		return;
  
  	remove_proc_entry(dev->proc_name, atm_proc_root);
  	kfree(dev->proc_name);
  }
  
  static struct atm_proc_entry {
  	char *name;

  	const struct file_operations *proc_fops;

  	struct proc_dir_entry *dirent;
  } atm_proc_ents[] = {
  	{ .name = "devices",	.proc_fops = &devices_seq_fops },
  	{ .name = "pvc",	.proc_fops = &pvc_seq_fops },
  	{ .name = "svc",	.proc_fops = &svc_seq_fops },
  	{ .name = "vc",		.proc_fops = &vcc_seq_fops },
  	{ .name = NULL,		.proc_fops = NULL }
  };
  
  static void atm_proc_dirs_remove(void)
  {
  	static struct atm_proc_entry *e;
  
  	for (e = atm_proc_ents; e->name; e++) {

  		if (e->dirent)

  			remove_proc_entry(e->name, atm_proc_root);
  	}

  	proc_net_remove(&init_net, "atm");

  }
  
  int __init atm_proc_init(void)
  {
  	static struct atm_proc_entry *e;
  	int ret;

  	atm_proc_root = proc_net_mkdir(&init_net, "atm", init_net.proc_net);

  	if (!atm_proc_root)
  		goto err_out;
  	for (e = atm_proc_ents; e->name; e++) {
  		struct proc_dir_entry *dirent;

  		dirent = proc_create(e->name, S_IRUGO,
  				     atm_proc_root, e->proc_fops);

  		if (!dirent)
  			goto err_out_remove;

  		e->dirent = dirent;
  	}
  	ret = 0;
  out:
  	return ret;
  
  err_out_remove:
  	atm_proc_dirs_remove();
  err_out:
  	ret = -ENOMEM;
  	goto out;
  }

  void atm_proc_exit(void)

  {
  	atm_proc_dirs_remove();
  }