/*
 * 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 1999 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#include "ghd.h"

/*
 * Round up all allocations so that we can guarantee
 * long-long alignment.  This is the same alignment
 * provided by kmem_alloc().
 */
#define ROUNDUP(x)      (((x) + 0x07) & ~0x07)

/*
 * Private wrapper for gcmd_t
 */
typedef struct gw_gcmd_and_length {
        gcmd_t  gcmd;           /* this must be first */
        int     glen;           /* length includes HBA private area */
}gw_t;

/*
 * round up the size so the HBA private area is on a 8 byte boundary
 */
#define GW_PADDED_LENGTH        ROUNDUP(sizeof (gw_t))

typedef struct gcmd_padded_wrapper {
        union {
                gw_t    gw;
                char    gw_pad[GW_PADDED_LENGTH];

        } gwrap;
} gwrap_t;

/*
 * Allocate a gcmd_t wrapper and HBA private area
 */

gcmd_t *
ghd_gcmd_alloc(gtgt_t   *gtgtp,
                int     ccblen,
                int     sleep)
{
        gwrap_t *gwp;
        gcmd_t  *gcmdp;
        int      gwrap_len;

        ccblen = ROUNDUP(ccblen);
        gwrap_len = sizeof (gwrap_t) + ccblen;
        gwp = kmem_zalloc(gwrap_len, (sleep ? KM_SLEEP : KM_NOSLEEP));
        if (gwp == NULL) {
                ASSERT(sleep == FALSE);
                return (NULL);
        }

        /* save the total length for the free function */
        gwp->gwrap.gw.glen = gwrap_len;

        /*
         * save the ptr to HBA private area and initialize all
         * the gcmd_t members and save
         */
        gcmdp = &gwp->gwrap.gw.gcmd;
        GHD_GCMD_INIT(gcmdp, (void *)(gwp + 1), gtgtp);
        return (gcmdp);
}



/*
 * Free the gcmd_t wrapper and HBA private area
 */

void
ghd_gcmd_free(gcmd_t *gcmdp)
{
        kmem_free(gcmdp, ((gw_t *)gcmdp)->glen);
}