root/net/kcm/kcmproc.c
// SPDX-License-Identifier: GPL-2.0
#include <linux/in.h>
#include <linux/inet.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/net.h>
#include <linux/proc_fs.h>
#include <linux/rculist.h>
#include <linux/seq_file.h>
#include <linux/socket.h>
#include <net/inet_sock.h>
#include <net/kcm.h>
#include <net/net_namespace.h>
#include <net/netns/generic.h>
#include <net/tcp.h>

#ifdef CONFIG_PROC_FS
static struct kcm_mux *kcm_get_first(struct seq_file *seq)
{
        struct net *net = seq_file_net(seq);
        struct kcm_net *knet = net_generic(net, kcm_net_id);

        return list_first_or_null_rcu(&knet->mux_list,
                                      struct kcm_mux, kcm_mux_list);
}

static struct kcm_mux *kcm_get_next(struct kcm_mux *mux)
{
        struct kcm_net *knet = mux->knet;

        return list_next_or_null_rcu(&knet->mux_list, &mux->kcm_mux_list,
                                     struct kcm_mux, kcm_mux_list);
}

static struct kcm_mux *kcm_get_idx(struct seq_file *seq, loff_t pos)
{
        struct net *net = seq_file_net(seq);
        struct kcm_net *knet = net_generic(net, kcm_net_id);
        struct kcm_mux *m;

        list_for_each_entry_rcu(m, &knet->mux_list, kcm_mux_list) {
                if (!pos)
                        return m;
                --pos;
        }
        return NULL;
}

static void *kcm_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
        void *p;

        if (v == SEQ_START_TOKEN)
                p = kcm_get_first(seq);
        else
                p = kcm_get_next(v);
        ++*pos;
        return p;
}

static void *kcm_seq_start(struct seq_file *seq, loff_t *pos)
        __acquires(rcu)
{
        rcu_read_lock();

        if (!*pos)
                return SEQ_START_TOKEN;
        else
                return kcm_get_idx(seq, *pos - 1);
}

static void kcm_seq_stop(struct seq_file *seq, void *v)
        __releases(rcu)
{
        rcu_read_unlock();
}

struct kcm_proc_mux_state {
        struct seq_net_private p;
        int idx;
};

static void kcm_format_mux_header(struct seq_file *seq)
{
        struct net *net = seq_file_net(seq);
        struct kcm_net *knet = net_generic(net, kcm_net_id);

        seq_printf(seq,
                   "*** KCM statistics (%d MUX) ****\n",
                   knet->count);

        seq_printf(seq,
                   "%-14s %-10s %-16s %-10s %-16s %-8s %-8s %-8s %-8s %s",
                   "Object",
                   "RX-Msgs",
                   "RX-Bytes",
                   "TX-Msgs",
                   "TX-Bytes",
                   "Recv-Q",
                   "Rmem",
                   "Send-Q",
                   "Smem",
                   "Status");

        /* XXX: pdsts header stuff here */
        seq_puts(seq, "\n");
}

static void kcm_format_sock(struct kcm_sock *kcm, struct seq_file *seq,
                            int i, int *len)
{
        seq_printf(seq,
                   "   kcm-%-7u %-10llu %-16llu %-10llu %-16llu %-8d %-8d %-8d %-8s ",
                   kcm->index,
                   kcm->stats.rx_msgs,
                   kcm->stats.rx_bytes,
                   kcm->stats.tx_msgs,
                   kcm->stats.tx_bytes,
                   kcm->sk.sk_receive_queue.qlen,
                   sk_rmem_alloc_get(&kcm->sk),
                   kcm->sk.sk_write_queue.qlen,
                   "-");

        if (kcm->tx_psock)
                seq_printf(seq, "Psck-%u ", kcm->tx_psock->index);

        if (kcm->tx_wait)
                seq_puts(seq, "TxWait ");

        if (kcm->tx_wait_more)
                seq_puts(seq, "WMore ");

        if (kcm->rx_wait)
                seq_puts(seq, "RxWait ");

        seq_puts(seq, "\n");
}

static void kcm_format_psock(struct kcm_psock *psock, struct seq_file *seq,
                             int i, int *len)
{
        seq_printf(seq,
                   "   psock-%-5u %-10llu %-16llu %-10llu %-16llu %-8d %-8d %-8d %-8d ",
                   psock->index,
                   psock->strp.stats.msgs,
                   psock->strp.stats.bytes,
                   psock->stats.tx_msgs,
                   psock->stats.tx_bytes,
                   psock->sk->sk_receive_queue.qlen,
                   atomic_read(&psock->sk->sk_rmem_alloc),
                   psock->sk->sk_write_queue.qlen,
                   refcount_read(&psock->sk->sk_wmem_alloc));

        if (psock->done)
                seq_puts(seq, "Done ");

        if (psock->tx_stopped)
                seq_puts(seq, "TxStop ");

        if (psock->strp.stopped)
                seq_puts(seq, "RxStop ");

        if (psock->tx_kcm)
                seq_printf(seq, "Rsvd-%d ", psock->tx_kcm->index);

        if (!psock->strp.paused && !psock->ready_rx_msg) {
                if (psock->sk->sk_receive_queue.qlen) {
                        if (psock->strp.need_bytes)
                                seq_printf(seq, "RxWait=%u ",
                                           psock->strp.need_bytes);
                        else
                                seq_printf(seq, "RxWait ");
                }
        } else  {
                if (psock->strp.paused)
                        seq_puts(seq, "RxPause ");

                if (psock->ready_rx_msg)
                        seq_puts(seq, "RdyRx ");
        }

        seq_puts(seq, "\n");
}

static void
kcm_format_mux(struct kcm_mux *mux, loff_t idx, struct seq_file *seq)
{
        int i, len;
        struct kcm_sock *kcm;
        struct kcm_psock *psock;

        /* mux information */
        seq_printf(seq,
                   "%-6s%-8s %-10llu %-16llu %-10llu %-16llu %-8s %-8s %-8s %-8s ",
                   "mux", "",
                   mux->stats.rx_msgs,
                   mux->stats.rx_bytes,
                   mux->stats.tx_msgs,
                   mux->stats.tx_bytes,
                   "-", "-", "-", "-");

        seq_printf(seq, "KCMs: %d, Psocks %d\n",
                   mux->kcm_socks_cnt, mux->psocks_cnt);

        /* kcm sock information */
        i = 0;
        spin_lock_bh(&mux->lock);
        list_for_each_entry(kcm, &mux->kcm_socks, kcm_sock_list) {
                kcm_format_sock(kcm, seq, i, &len);
                i++;
        }
        i = 0;
        list_for_each_entry(psock, &mux->psocks, psock_list) {
                kcm_format_psock(psock, seq, i, &len);
                i++;
        }
        spin_unlock_bh(&mux->lock);
}

static int kcm_seq_show(struct seq_file *seq, void *v)
{
        struct kcm_proc_mux_state *mux_state;

        mux_state = seq->private;
        if (v == SEQ_START_TOKEN) {
                mux_state->idx = 0;
                kcm_format_mux_header(seq);
        } else {
                kcm_format_mux(v, mux_state->idx, seq);
                mux_state->idx++;
        }
        return 0;
}

static const struct seq_operations kcm_seq_ops = {
        .show   = kcm_seq_show,
        .start  = kcm_seq_start,
        .next   = kcm_seq_next,
        .stop   = kcm_seq_stop,
};

static int kcm_stats_seq_show(struct seq_file *seq, void *v)
{
        struct kcm_psock_stats psock_stats;
        struct kcm_mux_stats mux_stats;
        struct strp_aggr_stats strp_stats;
        struct kcm_mux *mux;
        struct kcm_psock *psock;
        struct net *net = seq->private;
        struct kcm_net *knet = net_generic(net, kcm_net_id);

        memset(&mux_stats, 0, sizeof(mux_stats));
        memset(&psock_stats, 0, sizeof(psock_stats));
        memset(&strp_stats, 0, sizeof(strp_stats));

        mutex_lock(&knet->mutex);

        aggregate_mux_stats(&knet->aggregate_mux_stats, &mux_stats);
        aggregate_psock_stats(&knet->aggregate_psock_stats,
                              &psock_stats);
        aggregate_strp_stats(&knet->aggregate_strp_stats,
                             &strp_stats);

        list_for_each_entry(mux, &knet->mux_list, kcm_mux_list) {
                spin_lock_bh(&mux->lock);
                aggregate_mux_stats(&mux->stats, &mux_stats);
                aggregate_psock_stats(&mux->aggregate_psock_stats,
                                      &psock_stats);
                aggregate_strp_stats(&mux->aggregate_strp_stats,
                                     &strp_stats);
                list_for_each_entry(psock, &mux->psocks, psock_list) {
                        aggregate_psock_stats(&psock->stats, &psock_stats);
                        save_strp_stats(&psock->strp, &strp_stats);
                }

                spin_unlock_bh(&mux->lock);
        }

        mutex_unlock(&knet->mutex);

        seq_printf(seq,
                   "%-8s %-10s %-16s %-10s %-16s %-10s %-10s %-10s %-10s %-10s\n",
                   "MUX",
                   "RX-Msgs",
                   "RX-Bytes",
                   "TX-Msgs",
                   "TX-Bytes",
                   "TX-Retries",
                   "Attach",
                   "Unattach",
                   "UnattchRsvd",
                   "RX-RdyDrops");

        seq_printf(seq,
                   "%-8s %-10llu %-16llu %-10llu %-16llu %-10u %-10u %-10u %-10u %-10u\n",
                   "",
                   mux_stats.rx_msgs,
                   mux_stats.rx_bytes,
                   mux_stats.tx_msgs,
                   mux_stats.tx_bytes,
                   mux_stats.tx_retries,
                   mux_stats.psock_attach,
                   mux_stats.psock_unattach_rsvd,
                   mux_stats.psock_unattach,
                   mux_stats.rx_ready_drops);

        seq_printf(seq,
                   "%-8s %-10s %-16s %-10s %-16s %-10s %-10s %-10s %-10s %-10s %-10s %-10s %-10s %-10s %-10s %-10s\n",
                   "Psock",
                   "RX-Msgs",
                   "RX-Bytes",
                   "TX-Msgs",
                   "TX-Bytes",
                   "Reserved",
                   "Unreserved",
                   "RX-Aborts",
                   "RX-Intr",
                   "RX-Unrecov",
                   "RX-MemFail",
                   "RX-NeedMor",
                   "RX-BadLen",
                   "RX-TooBig",
                   "RX-Timeout",
                   "TX-Aborts");

        seq_printf(seq,
                   "%-8s %-10llu %-16llu %-10llu %-16llu %-10llu %-10llu %-10u %-10u %-10u %-10u %-10u %-10u %-10u %-10u %-10u\n",
                   "",
                   strp_stats.msgs,
                   strp_stats.bytes,
                   psock_stats.tx_msgs,
                   psock_stats.tx_bytes,
                   psock_stats.reserved,
                   psock_stats.unreserved,
                   strp_stats.aborts,
                   strp_stats.interrupted,
                   strp_stats.unrecov_intr,
                   strp_stats.mem_fail,
                   strp_stats.need_more_hdr,
                   strp_stats.bad_hdr_len,
                   strp_stats.msg_too_big,
                   strp_stats.msg_timeouts,
                   psock_stats.tx_aborts);

        return 0;
}

static int kcm_proc_init_net(struct net *net)
{
        if (!proc_create_net_single("kcm_stats", 0444, net->proc_net,
                         kcm_stats_seq_show, NULL))
                goto out_kcm_stats;

        if (!proc_create_net("kcm", 0444, net->proc_net, &kcm_seq_ops,
                        sizeof(struct kcm_proc_mux_state)))
                goto out_kcm;

        return 0;

out_kcm:
        remove_proc_entry("kcm_stats", net->proc_net);
out_kcm_stats:
        return -ENOMEM;
}

static void kcm_proc_exit_net(struct net *net)
{
        remove_proc_entry("kcm", net->proc_net);
        remove_proc_entry("kcm_stats", net->proc_net);
}

static struct pernet_operations kcm_net_ops = {
        .init = kcm_proc_init_net,
        .exit = kcm_proc_exit_net,
};

int __init kcm_proc_init(void)
{
        return register_pernet_subsys(&kcm_net_ops);
}

void __exit kcm_proc_exit(void)
{
        unregister_pernet_subsys(&kcm_net_ops);
}

#endif /* CONFIG_PROC_FS */