v9/syscall/install_utrap.c

	install_utrap.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (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 2005 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

#include <sys/types.h>
#include <sys/errno.h>
#include <sys/systm.h>
#include <sys/atomic.h>
#include <sys/kmem.h>
#include <sys/machpcb.h>
#include <sys/utrap.h>
#include <sys/model.h>
#include <sys/cmn_err.h>

int
install_utrap(utrap_entry_t type, utrap_handler_t new_handler,
    utrap_handler_t *old_handlerp)
{
    struct proc *p = curthread->t_procp;
    utrap_handler_t *ov, *nv, *pv, *sv, *tmp;
    int idx;

    /*
     * Check trap number.
     */
    switch (type) {
    case UTRAP_V8P_FP_DISABLED:
#ifdef SF_ERRATA_30 /* call causes fp-disabled */
        {
        extern int spitfire_call_bug;

        if (spitfire_call_bug) {
            cmn_err(CE_WARN, "UTRAP_V8P_FP_DISABLED "
                "not supported for cpu version < 2.2");
            return ((int)set_errno(ENOSYS));
        }
        }
#endif /* SF_ERRATA_30 */
        idx = UTRAP_V8P_FP_DISABLED;
        break;
    case UTRAP_V8P_MEM_ADDRESS_NOT_ALIGNED:
        idx = UTRAP_V8P_MEM_ADDRESS_NOT_ALIGNED;
        break;
    default:
        return ((int)set_errno(EINVAL));
    }
    if (get_udatamodel() == DATAMODEL_LP64) {
        cmn_err(CE_WARN, "install_utrap private interface "
            "not supported for LP64 user programs");
        return ((int)set_errno(EINVAL));
    }

    /*
     * Be sure handler address is word aligned.
     */
    nv = (utrap_handler_t *)(caddr32_t)new_handler;
    if (nv != UTRAP_UTH_NOCHANGE) {
        if (((uintptr_t)nv) & 0x3)
            return ((int)set_errno(EINVAL));
    }
    /*
     * Allocate proc space for saving the addresses to these user
     * trap handlers, which must later be freed. Use casptr to
     * do this atomically.
     */
    if (p->p_utraps == NULL) {
        pv = sv = kmem_zalloc((UT_PRECISE_MAXTRAPS+1) *
            sizeof (utrap_handler_t *), KM_SLEEP);
        tmp = casptr(&p->p_utraps, NULL, sv);
        if (tmp != NULL) {
            kmem_free(pv, (UT_PRECISE_MAXTRAPS+1) *
                sizeof (utrap_handler_t *));
        }
    }
    ASSERT(p->p_utraps != NULL);

    /*
     * Use casptr to atomically install the handler.
     */
    ov = p->p_utraps[idx];
    if (new_handler != (utrap_handler_t)UTRAP_UTH_NOCHANGE) {
        for (;;) {
            tmp = casptr(&p->p_utraps[idx], ov, nv);
            if (ov == tmp)
                break;
            ov = tmp;
        }
    }
    if (old_handlerp != NULL) {
        if (suword32(old_handlerp, (uint32_t)ov) == -1)
            return ((int)set_errno(EINVAL));
    }
    return (0);
}

void
utrap_dup(struct proc *pp, struct proc *cp)
{
    if (pp->p_utraps != NULL) {
        cp->p_utraps = kmem_alloc((UT_PRECISE_MAXTRAPS+1) *
            sizeof (utrap_handler_t *), KM_SLEEP);
        bcopy(pp->p_utraps, cp->p_utraps,
            (UT_PRECISE_MAXTRAPS+1) * sizeof (utrap_handler_t *));
    } else {
        cp->p_utraps = NULL;
    }
}

void
utrap_free(struct proc *p)
{
    /* Free any kmem_alloc'ed space for user trap handlers. */
    if (p->p_utraps != NULL) {
        kmem_free(p->p_utraps, (UT_PRECISE_MAXTRAPS+1) *
            sizeof (utrap_handler_t *));
        p->p_utraps = NULL;
    }
}

/*
 * The code below supports the set of user traps which are required and
 * "must be provided by all ABI-conforming implementations", according to
 * 3.3.3 User Traps of the SPARC V9 ABI SUPPLEMENT, Delta Document 1.38.
 * There is only 1 deferred trap in Ultra I&II, the asynchronous error
 * traps, which are not required, so the deferred args are not used.
 */
/*ARGSUSED*/
int
sparc_utrap_install(utrap_entry_t type,
    utrap_handler_t new_precise, utrap_handler_t new_deferred,
    utrap_handler_t *old_precise, utrap_handler_t *old_deferred)
{
    struct proc *p = curthread->t_procp;
    utrap_handler_t *ov, *nvp, *pv, *sv, *tmp;
    int idx;

    /*
     * Check trap number.
     */
    switch (type) {
    case UT_ILLTRAP_INSTRUCTION:
        idx = UT_ILLTRAP_INSTRUCTION;
        break;
    case UT_FP_DISABLED:
#ifdef SF_ERRATA_30 /* call causes fp-disabled */
        {
        extern int spitfire_call_bug;

        if (spitfire_call_bug) {
            cmn_err(CE_WARN, "UT_FP_DISABLED "
                "not supported for cpu version < 2.2");
            return ((int)set_errno(ENOSYS));
        }
        }
#endif /* SF_ERRATA_30 */
        idx = UT_FP_DISABLED;
        break;
    case UT_FP_EXCEPTION_IEEE_754:
        idx = UT_FP_EXCEPTION_IEEE_754;
        break;
    case UT_TAG_OVERFLOW:
        idx = UT_TAG_OVERFLOW;
        break;
    case UT_DIVISION_BY_ZERO:
        idx = UT_DIVISION_BY_ZERO;
        break;
    case UT_MEM_ADDRESS_NOT_ALIGNED:
        idx = UT_MEM_ADDRESS_NOT_ALIGNED;
        break;
    case UT_PRIVILEGED_ACTION:
        idx = UT_PRIVILEGED_ACTION;
        break;
    case UT_TRAP_INSTRUCTION_16:
    case UT_TRAP_INSTRUCTION_17:
    case UT_TRAP_INSTRUCTION_18:
    case UT_TRAP_INSTRUCTION_19:
    case UT_TRAP_INSTRUCTION_20:
    case UT_TRAP_INSTRUCTION_21:
    case UT_TRAP_INSTRUCTION_22:
    case UT_TRAP_INSTRUCTION_23:
    case UT_TRAP_INSTRUCTION_24:
    case UT_TRAP_INSTRUCTION_25:
    case UT_TRAP_INSTRUCTION_26:
    case UT_TRAP_INSTRUCTION_27:
    case UT_TRAP_INSTRUCTION_28:
    case UT_TRAP_INSTRUCTION_29:
    case UT_TRAP_INSTRUCTION_30:
    case UT_TRAP_INSTRUCTION_31:
        idx = type;
        break;
    default:
        return ((int)set_errno(EINVAL));
    }

    if (get_udatamodel() == DATAMODEL_ILP32) {
        cmn_err(CE_WARN, "__sparc_utrap_install interface "
            "not supported for ILP32 user programs");
        return ((int)set_errno(EINVAL));
    }

    /*
     * Be sure handler address is word aligned.
     * There are no deferred traps, so ignore them.
     */
    nvp = (utrap_handler_t *)new_precise;
    if (nvp != UTRAP_UTH_NOCHANGE) {
        if (((uintptr_t)nvp) & 0x3)
            return ((int)set_errno(EINVAL));
    }

    /*
     * Allocate proc space for saving the addresses to these user
     * trap handlers, which must later be freed. Use casptr to
     * do this atomically.
     */
    if (p->p_utraps == NULL) {
        pv = sv = kmem_zalloc((UT_PRECISE_MAXTRAPS+1) *
            sizeof (utrap_handler_t *), KM_SLEEP);
        tmp = casptr(&p->p_utraps, NULL, sv);
        if (tmp != NULL) {
            kmem_free(pv, (UT_PRECISE_MAXTRAPS+1) *
                sizeof (utrap_handler_t *));
        }
    }
    ASSERT(p->p_utraps != NULL);

    /*
     * Use casptr to atomically install the handlers.
     */
    ov = p->p_utraps[idx];
    if (new_precise != (utrap_handler_t)UTH_NOCHANGE) {
        for (;;) {
            tmp = casptr(&p->p_utraps[idx], ov, nvp);
            if (ov == tmp)
                break;
            ov = tmp;
        }
    }
    if (old_precise != NULL) {
        if (suword64(old_precise, (uint64_t)ov) == -1)
            return ((int)set_errno(EINVAL));
    }
    return (0);
}