/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
 */
#include <sys/types.h>
#include <sys/sunddi.h>
#include <sys/dlpi.h>
#include <sys/ib/clients/rdsv3/rdsv3_sc.h>
#include <sys/ib/clients/rdsv3/rdsv3_debug.h>

/*
 * RDS Path MAP
 *
 * N - Node record, P - Path record
 *
 * rds_path_map -
 *              |
 *              v
 *              ---------       ---------       ---------
 *              |   N   |------>|  N    |------>|   N   |------> NULL
 * NULL <-------|       |<------|       |<------|       |
 *              ---------       ---------       ---------
 *               |               |               |
 *               |               |               |
 *               v               v               v
 *              --------        ---------       ---------
 *              |  P   |        |  P    |       |  P    |
 *              --------        ---------       ---------
 *              |  ^            |   ^           |   ^
 *              |  |            |   |           |   |
 *              v  |            v   |           v   |
 *              --------        --------        ---------
 *              |   P  |        |  P   |        |  P    |
 *              --------        --------        ---------
 *                o                o               o
 *                o                o               o
 *                o                o               o
 */

typedef struct rds_path_record_s {
        ipaddr_t                        libd_ip;
        ipaddr_t                        ribd_ip;
        struct rds_path_record_s        *up;
        struct rds_path_record_s        *downp;
        char                            lifname[MAXNAMELEN];
        char                            rifname[MAXNAMELEN];
} rds_path_record_t;

typedef struct rds_node_record_s {
        struct rds_node_record_s        *nextp;
        ipaddr_t                        lnode_ip;       /* local ip */
        ipaddr_t                        rnode_ip;       /* remote ip */
        struct rds_path_record_s        *downp;
        struct rds_node_record_s        *prevp;
} rds_node_record_t;

static char                     sc_device_name[MAXNAMELEN] = "NotInitialized";
static kmutex_t                 rdsv3_pathmap_lock;
static rds_node_record_t        *rdsv3_pathmap = NULL;

#define RDS_VALIDATE_PATH(p)                                            \
        if ((p->local.iftype != DL_IB) || (p->remote.iftype != DL_IB))  \
                return

#define isalpha(ch)     (((ch) >= 'a' && (ch) <= 'z') || \
                        ((ch) >= 'A' && (ch) <= 'Z'))

/*
 * Called by SC to register the Sun Cluster device name
 */
void
rdsv3_clif_name(char *name)
{
        int     i;

        ASSERT(name != NULL);

        mutex_enter(&rdsv3_pathmap_lock);

        /* extract the device name from the interface name */
        i = strlen(name) - 1;
        while ((i >= 0) && (!isalpha(name[i]))) i--;
        if (i >= 0) {
                (void) strncpy(sc_device_name, name, i + 1);
                sc_device_name[i + 1] = '\0';
        }

        mutex_exit(&rdsv3_pathmap_lock);
}

/*
 * Called by SC on discovering a new path
 */
void
rdsv3_path_up(rds_path_t *path)
{
        rds_node_record_t       *p;
        rds_path_record_t       *p1;

        ASSERT(path != NULL);

        /* ignore if the end points are not of type DL_IB */
        RDS_VALIDATE_PATH(path);

        mutex_enter(&rdsv3_pathmap_lock);

        p = rdsv3_pathmap;
        while ((p) && ((p->lnode_ip != path->local.node_ipaddr) ||
            (p->rnode_ip != path->remote.node_ipaddr))) {
                p = p->nextp;
        }

        if (p == NULL) {
                p = (rds_node_record_t *)kmem_alloc(sizeof (rds_node_record_t),
                    KM_SLEEP);
                p1 = (rds_path_record_t *)kmem_alloc(
                    sizeof (rds_path_record_t), KM_SLEEP);

                p->nextp = NULL;
                p->lnode_ip = path->local.node_ipaddr;
                p->rnode_ip = path->remote.node_ipaddr;
                p->downp = p1;
                p->prevp = NULL;

                p1->libd_ip = path->local.ipaddr;
                p1->ribd_ip = path->remote.ipaddr;
                p1->up = NULL;
                p1->downp = NULL;
                (void) strcpy(p1->lifname, path->local.ifname);
                (void) strcpy(p1->rifname, path->remote.ifname);

                if (rdsv3_pathmap == NULL) {
                        rdsv3_pathmap = p;
                } else {
                        /* insert this node at the head */
                        rdsv3_pathmap->prevp = p;
                        p->nextp = rdsv3_pathmap;
                        rdsv3_pathmap = p;
                }
        } else {
                /* we found a match */
                p1 = (rds_path_record_t *)kmem_alloc(
                    sizeof (rds_path_record_t), KM_SLEEP);

                p1->libd_ip = path->local.ipaddr;
                p1->ribd_ip = path->remote.ipaddr;
                p1->downp = p->downp;
                p->downp->up = p1;
                p1->up = NULL;
                p->downp = p1;
                (void) strcpy(p1->lifname, path->local.ifname);
                (void) strcpy(p1->rifname, path->remote.ifname);
        }

        mutex_exit(&rdsv3_pathmap_lock);
}

/*
 * Called by SC to delete a path
 */
void
rdsv3_path_down(rds_path_t *path)
{
        rds_node_record_t       *p;
        rds_path_record_t       *p1, *p1up, *p1downp;

        ASSERT(path != NULL);

        /* ignore if the end points are not of type DL_IB */
        RDS_VALIDATE_PATH(path);

        mutex_enter(&rdsv3_pathmap_lock);

        p = rdsv3_pathmap;
        while ((p) && ((p->lnode_ip != path->local.node_ipaddr) ||
            (p->rnode_ip != path->remote.node_ipaddr))) {
                p = p->nextp;
        }

        if (p == NULL) {
                /* no match */
                RDSV3_DPRINTF2("rdsv3_path_down", "Node record not found "
                    "(0x%x <-> 0x%x)", path->local.node_ipaddr,
                    path->remote.node_ipaddr);
                mutex_exit(&rdsv3_pathmap_lock);
                return;
        }

        p1 = p->downp;
        while ((p1) && ((p1->libd_ip != path->local.ipaddr) ||
            (p1->ribd_ip != path->remote.ipaddr))) {
                p1 = p1->downp;
        }

        if (p1 == NULL) {
                /* no match */
                RDSV3_DPRINTF2("rdsv3_path_down", "Path record not found "
                    "(0x%x <-> 0x%x)", path->local.ipaddr, path->remote.ipaddr);
                mutex_exit(&rdsv3_pathmap_lock);
                return;
        }

        /* we found the record, remove it */
        p1up = p1->up;
        p1downp = p1->downp;

        if (p1up) {
                p1up->downp = p1downp;
        } else {
                /* this is the first path record */
                p->downp = p1downp;
        }

        if (p1downp) {
                p1downp->up = p1up;
        }

        kmem_free(p1, sizeof (rds_path_record_t));

        /* remove the node record if there are no path records */
        if (p->downp == NULL) {
                if (p->prevp) {
                        p->prevp->nextp = p->nextp;
                } else {
                        /* this is the first node record */
                        ASSERT(p == rdsv3_pathmap);
                        rdsv3_pathmap = p->nextp;
                }

                if (p->nextp) {
                        p->nextp->prevp = p->prevp;
                }

                kmem_free(p, sizeof (rds_node_record_t));
        }

        mutex_exit(&rdsv3_pathmap_lock);
}

int
rdsv3_sc_path_lookup(ipaddr_t *localip, ipaddr_t *remip)
{
        rds_node_record_t       *p;
        rds_path_record_t       *p1, *p1downp;

        mutex_enter(&rdsv3_pathmap_lock);

        p = rdsv3_pathmap;
        while ((p) && ((p->lnode_ip != *localip) || (p->rnode_ip != *remip))) {
                p = p->nextp;
        }

        if (p == NULL) {
                /* no match */
                RDSV3_DPRINTF2("rdsv3_sc_path_lookup", "Node record not found "
                    "(0x%x <-> 0x%x)", *localip, *remip);
                mutex_exit(&rdsv3_pathmap_lock);
                return (0);
        }

        /* found a path */
        p1 = p->downp;
        *localip = p1->libd_ip;
        *remip = p1->ribd_ip;

        /*
         * But next time, we want to use a different path record so move this
         * path record to the end.
         */
        p1downp = p1->downp;
        if (p1downp != NULL) {
                p->downp = p1downp;
                p1downp->up = NULL;

                /* walk down to the last path record */
                while (p1downp->downp != NULL) {
                        p1downp = p1downp->downp;
                }

                /* Attach the first path record to the end */
                p1downp->downp = p1;
                p1->up = p1downp;
                p1->downp = NULL;
        }

        mutex_exit(&rdsv3_pathmap_lock);

        return (1);
}

boolean_t
rdsv3_if_lookup_by_name(char *devname)
{
        mutex_enter(&rdsv3_pathmap_lock);

        /*
         * Sun Cluster always names its interconnect virtual network interface
         * as clprivnetx, so  return TRUE if there is atleast one node record
         * and the interface name is clprivnet something.
         */
        if (strcmp(devname, sc_device_name) == 0) {
                /* clprivnet address */
                mutex_exit(&rdsv3_pathmap_lock);
                return (B_TRUE);
        }

        mutex_exit(&rdsv3_pathmap_lock);
        return (B_FALSE);
}

boolean_t
rdsv3_if_lookup_by_addr(ipaddr_t addr)
{
        rds_node_record_t       *p;
        rds_path_record_t       *p1;

        mutex_enter(&rdsv3_pathmap_lock);

        p = rdsv3_pathmap;
        while ((p) && (p->lnode_ip != addr)) {
                p1 = p->downp;
                while ((p1) && (p1->libd_ip != addr)) {
                        p1 = p1->downp;
                }

                /* we found a match */
                if (p1 != NULL)
                        break;

                /* go to the next node record */
                p = p->nextp;
        }

        mutex_exit(&rdsv3_pathmap_lock);
        if (p == NULL) {
                /* no match */
                RDSV3_DPRINTF2("rds_if_lookup_by_addr",
                    "Addr: 0x%x not found", addr);
                return (B_FALSE);
        }

        /* Found a matching node record */
        return (B_TRUE);
}

/*
 * If SC is configured then addr would be a clprivnet address. Find the
 * node record and return the first IB address. If the node record is not
 * found, then return addr as-is.
 */
ipaddr_t
rdsv3_scaddr_to_ibaddr(ipaddr_t addr)
{
        rds_node_record_t       *p;
        rds_path_record_t       *p1;
        ipaddr_t                ret = addr;

        mutex_enter(&rdsv3_pathmap_lock);

        p = rdsv3_pathmap;
        while ((p) && (p->lnode_ip != addr)) {
                /* go to the next node record */
                p = p->nextp;
        }

        if (p != NULL) {
                p1 = p->downp;
                ret = p1->libd_ip;
                RDSV3_DPRINTF3("rds_scaddr_to_ibaddr",
                    "Addr: 0x%x found: 0x%x", addr, p1->libd_ip);
        }
        mutex_exit(&rdsv3_pathmap_lock);

        /* Found a matching node record */
        return (ret);
}