/*
 * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
 */

/*
 * This file contains code imported from the OFED rds source file bind.c
 * Oracle elects to have and use the contents of bind.c under and governed
 * by the OpenIB.org BSD license (see below for full license text). However,
 * the following notice accompanied the original version of this file:
 */

/*
 * Copyright (c) 2006 Oracle.  All rights reserved.
 *
 * This software is available to you under a choice of one of two
 * licenses.  You may choose to be licensed under the terms of the GNU
 * General Public License (GPL) Version 2, available from the file
 * COPYING in the main directory of this source tree, or the
 * OpenIB.org BSD license below:
 *
 *     Redistribution and use in source and binary forms, with or
 *     without modification, are permitted provided that the following
 *     conditions are met:
 *
 *      - Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer.
 *
 *      - Redistributions in binary form must reproduce the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer in the documentation and/or other materials
 *        provided with the distribution.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 *
 */
#include <sys/types.h>
#include <sys/sysmacros.h>
#include <sys/random.h>
#include <sys/rds.h>

#include <sys/ib/clients/rdsv3/rdsv3.h>
#include <sys/ib/clients/rdsv3/rdsv3_debug.h>

kmutex_t        rdsv3_bind_lock;
avl_tree_t      rdsv3_bind_tree;

/*
 * Each node in the rdsv3_bind_tree is of this type.
 */
struct rdsv3_ip_bucket {
        ipaddr_t                ip;
        zoneid_t                zone;
        avl_node_t              ip_avl_node;
        krwlock_t               rwlock;
        uint_t                  nsockets;
        struct rdsv3_sock       *port[65536];
};

static int
rdsv3_bind_node_compare(const void *a, const void *b)
{
        struct rdsv3_ip_bucket *bp = (struct rdsv3_ip_bucket *)b;

        if (*(uint64_t *)a > (((uint64_t)bp->ip << 32) | bp->zone))
                return (+1);
        else if (*(uint64_t *)a < (((uint64_t)bp->ip << 32) | bp->zone))
                return (-1);

        return (0);
}

void
rdsv3_bind_init()
{
        RDSV3_DPRINTF4("rdsv3_bind_tree_init", "Enter");

        mutex_init(&rdsv3_bind_lock, NULL, MUTEX_DRIVER, NULL);
        avl_create(&rdsv3_bind_tree, rdsv3_bind_node_compare,
            sizeof (struct rdsv3_ip_bucket),
            offsetof(struct rdsv3_ip_bucket, ip_avl_node));

        RDSV3_DPRINTF4("rdsv3_bind_tree_init", "Return");
}

/* called on detach */
void
rdsv3_bind_exit()
{
        struct rdsv3_ip_bucket  *bucketp;
        void                    *cookie = NULL;

        RDSV3_DPRINTF2("rdsv3_bind_tree_exit", "Enter");

        while ((bucketp =
            avl_destroy_nodes(&rdsv3_bind_tree, &cookie)) != NULL) {
                rw_destroy(&bucketp->rwlock);
                kmem_free(bucketp, sizeof (struct rdsv3_ip_bucket));
        }

        avl_destroy(&rdsv3_bind_tree);
        mutex_destroy(&rdsv3_bind_lock);

        RDSV3_DPRINTF2("rdsv3_bind_tree_exit", "Return");
}

struct rdsv3_ip_bucket *
rdsv3_find_ip_bucket(ipaddr_t ipaddr, zoneid_t zoneid)
{
        struct rdsv3_ip_bucket  *bucketp;
        avl_index_t             where;
        uint64_t                needle = ((uint64_t)ipaddr << 32) | zoneid;

        mutex_enter(&rdsv3_bind_lock);
        bucketp = avl_find(&rdsv3_bind_tree, &needle, &where);
        if (bucketp == NULL) {
                /* allocate a new bucket for this IP & zone */
                bucketp =
                    kmem_zalloc(sizeof (struct rdsv3_ip_bucket), KM_SLEEP);
                rw_init(&bucketp->rwlock, NULL, RW_DRIVER, NULL);
                bucketp->ip = ipaddr;
                bucketp->zone = zoneid;
                avl_insert(&rdsv3_bind_tree, bucketp, where);
        }
        mutex_exit(&rdsv3_bind_lock);

        return (bucketp);
}

/*
 * Return the rdsv3_sock bound at the given local address.
 *
 * The rx path can race with rdsv3_release.  We notice if rdsv3_release() has
 * marked this socket and don't return a rs ref to the rx path.
 */
struct rdsv3_sock *
rdsv3_find_bound(struct rdsv3_connection *conn, uint16_be_t port)
{
        struct rdsv3_sock *rs;

        RDSV3_DPRINTF4("rdsv3_find_bound", "Enter(ip:port: %u.%u.%u.%u:%d)",
            NIPQUAD(conn->c_laddr), ntohs(port));

        rw_enter(&conn->c_bucketp->rwlock, RW_READER);
        ASSERT(ntohl(conn->c_laddr) == conn->c_bucketp->ip);
        rs = conn->c_bucketp->port[ntohs(port)];
        if (rs && !rdsv3_sk_sock_flag(rdsv3_rs_to_sk(rs), SOCK_DEAD))
                rdsv3_sk_sock_hold(rdsv3_rs_to_sk(rs));
        else
                rs = NULL;
        rw_exit(&conn->c_bucketp->rwlock);

        RDSV3_DPRINTF5("rdsv3_find_bound", "returning rs %p for %u.%u.%u.%u:%d",
            rs, NIPQUAD(conn->c_laddr), ntohs(port));

        return (rs);
}

/* returns -ve errno or +ve port */
static int
rdsv3_add_bound(struct rdsv3_sock *rs, uint32_be_t addr, uint16_be_t *port)
{
        int ret = -EADDRINUSE;
        uint16_t rover, last;
        struct rdsv3_ip_bucket *bucketp;

        RDSV3_DPRINTF4("rdsv3_add_bound", "Enter(addr:port: %x:%x)",
            ntohl(addr), ntohs(*port));

        if (*port != 0) {
                rover = ntohs(*port);
                last = rover;
        } else {
                (void) random_get_pseudo_bytes((uint8_t *)&rover,
                    sizeof (uint16_t));
                rover = MAX(rover, 2);
                last = rover - 1;
        }

        bucketp = rdsv3_find_ip_bucket(ntohl(addr), rs->rs_zoneid);

        /* leave the bind lock and get the bucket lock */
        rw_enter(&bucketp->rwlock, RW_WRITER);

        do {
                if (rover == 0)
                        rover++;

                if (bucketp->port[rover] == NULL) {
                        *port = htons(rover);
                        ret = 0;
                        break;
                }
        } while (rover++ != last);

        if (ret == 0)  {
                rs->rs_bound_addr = addr;
                rs->rs_bound_port = *port;
                bucketp->port[rover] = rs;
                bucketp->nsockets++;
                rdsv3_sock_addref(rs);

                RDSV3_DPRINTF5("rdsv3_add_bound",
                    "rs %p binding to %u.%u.%u.%u:%d",
                    rs, NIPQUAD(addr), rover);
        }

        rw_exit(&bucketp->rwlock);

        RDSV3_DPRINTF4("rdsv3_add_bound", "Return(ret: %d port: %d)",
            ret, rover);


        return (ret);
}

void
rdsv3_remove_bound(struct rdsv3_sock *rs)
{
        RDSV3_DPRINTF4("rdsv3_remove_bound", "Enter(rs: %p)", rs);

        if (rs->rs_bound_addr) {
                struct rdsv3_ip_bucket *bucketp;

                RDSV3_DPRINTF5("rdsv3_remove_bound",
                    "rs %p unbinding from %u.%u.%u.%u:%x",
                    rs, NIPQUAD(htonl(rs->rs_bound_addr)), rs->rs_bound_port);

                bucketp = rdsv3_find_ip_bucket(ntohl(rs->rs_bound_addr),
                    rs->rs_zoneid);

                rw_enter(&bucketp->rwlock, RW_WRITER);
                bucketp->port[ntohs(rs->rs_bound_port)] = NULL;
                bucketp->nsockets--;
                rs->rs_bound_addr = 0;
                rw_exit(&bucketp->rwlock);

                rdsv3_sock_put(rs);
        }

        RDSV3_DPRINTF4("rdsv3_remove_bound", "Return(rs: %p)", rs);
}

/* ARGSUSED */
int
rdsv3_bind(sock_lower_handle_t proto_handle, struct sockaddr *sa,
    socklen_t len, cred_t *cr)
{
        struct rsock    *sk = (struct rsock *)proto_handle;
        sin_t           *sin = (sin_t *)sa;
        struct rdsv3_sock       *rs = rdsv3_sk_to_rs(sk);
        int             ret;

        if (len != sizeof (sin_t) || (sin == NULL) ||
            !OK_32PTR((char *)sin)) {
                RDSV3_DPRINTF2("rdsv3_bind", "address to bind not specified");
                return (EINVAL);
        }

        RDSV3_DPRINTF4("rdsv3_bind", "Enter(rs: %p, addr: 0x%x, port: %x)",
            rs, ntohl(sin->sin_addr.s_addr), htons(sin->sin_port));

        if (sin->sin_addr.s_addr == INADDR_ANY) {
                RDSV3_DPRINTF2("rdsv3_bind", "Invalid address");
                return (EINVAL);
        }

        /* We don't allow multiple binds */
        if (rs->rs_bound_addr) {
                RDSV3_DPRINTF2("rdsv3_bind", "Multiple binds not allowed");
                return (EINVAL);
        }

        ret = rdsv3_add_bound(rs, sin->sin_addr.s_addr, &sin->sin_port);
        if (ret) {
                return (ret);
        }

        rs->rs_transport = rdsv3_trans_get_preferred(sin->sin_addr.s_addr);
        if (!rs->rs_transport) {
                rdsv3_remove_bound(rs);
                if (rdsv3_printk_ratelimit()) {
                        RDSV3_DPRINTF1("rdsv3_bind",
                            "RDS: rdsv3_bind() could not find a transport.\n");
                }
                return (EADDRNOTAVAIL);
        }

        RDSV3_DPRINTF4("rdsv3_bind", "Return: Assigned port: %x to sock: %p",
            sin->sin_port, rs);

        return (0);
}