/* 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 <net/net_namespace.h>
#include <net/atmclip.h>
#include <asm/uaccess.h>
#include <asm/atomic.h>
#include <asm/param.h> /* for HZ */
#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,
};

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, '\n');
}

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 == (void *)1) {
                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 = (void *)1;
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;
        struct seq_file *seq;
        int rc = -ENOMEM;

        state = kmalloc(sizeof(*state), GFP_KERNEL);
        if (!state)
                goto out;

        rc = seq_open(file, ops);
        if (rc)
                goto out_kfree;

        state->family = family;

        seq = file->private_data;
        seq->private = state;
out:
        return rc;
out_kfree:
        kfree(state);
        goto out;
}

static int vcc_seq_release(struct inode *inode, struct file *file)
{
        return seq_release_private(inode, file);
}

static void *vcc_seq_start(struct seq_file *seq, loff_t *pos)
{
        struct vcc_state *state = seq->private;
        loff_t left = *pos;

        read_lock(&vcc_sklist_lock);
        state->sk = (void *)1;
        return left ? vcc_walk(state, left) : (void *)1;
}

static void vcc_seq_stop(struct seq_file *seq, void *v)
{
        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 *class_name[] = { "off","UBR","CBR","VBR","ABR" };
        static const char *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, '\n');
}

static const char *vcc_state(struct atm_vcc *vcc)
{
        static const char *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, "%p ", 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]\n", vcc->flags, sk->sk_err,
                  atomic_read(&sk->sk_wmem_alloc), sk->sk_sndbuf,
                  atomic_read(&sk->sk_rmem_alloc), 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@%p%10s" : "N/A@%p%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, '\n');
}

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]\n";

        if (v == (void *)1)
                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)\n";

        if (v == (void *)1)
                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        = vcc_seq_release,
};

static int vcc_seq_show(struct seq_file *seq, void *v)
{
        if (v == (void *)1) {
                seq_printf(seq, sizeof(void *) == 4 ? "%-8s%s" : "%-16s%s",
                        "Address ", "Itf VPI VCI   Fam Flags Reply "
                        "Send buffer     Recv buffer      [refcnt]\n");
        } 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        = vcc_seq_release,
};

static int svc_seq_show(struct seq_file *seq, void *v)
{
        static char atm_svc_banner[] =
                "Itf VPI VCI           State      Remote\n";

        if (v == (void *)1)
                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        = vcc_seq_release,
};

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 digits,num;
        int error;

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

        error = -ENOMEM;
        digits = 0;
        for (num = dev->number; num; num /= 10) digits++;
        if (!digits) digits++;

        dev->proc_name = kmalloc(strlen(dev->type) + digits + 2, GFP_KERNEL);
        if (!dev->proc_name)
                goto err_out;
        sprintf(dev->proc_name,"%s:%d",dev->type, dev->number);

        dev->proc_entry = create_proc_entry(dev->proc_name, 0, atm_proc_root);
        if (!dev->proc_entry)
                goto err_free_name;
        dev->proc_entry->data = dev;
        dev->proc_entry->proc_fops = &proc_atm_dev_ops;
        dev->proc_entry->owner = THIS_MODULE;
        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);
        }
        remove_proc_entry("atm", init_net.proc_net);
}

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

        atm_proc_root = proc_mkdir("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 = create_proc_entry(e->name, S_IRUGO, atm_proc_root);
                if (!dirent)
                        goto err_out_remove;
                dirent->proc_fops = e->proc_fops;
                dirent->owner = THIS_MODULE;
                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();
}