[apple/xnu.git] / osfmk / kern / ipc_host.c

/*
 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this
 * file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
/*
 * @OSF_COPYRIGHT@
 */
/* 
 * Mach Operating System
 * Copyright (c) 1991,1990,1989,1988 Carnegie Mellon University
 * All Rights Reserved.
 * 
 * Permission to use, copy, modify and distribute this software and its
 * documentation is hereby granted, provided that both the copyright
 * notice and this permission notice appear in all copies of the
 * software, derivative works or modified versions, and any portions
 * thereof, and that both notices appear in supporting documentation.
 * 
 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
 * 
 * Carnegie Mellon requests users of this software to return to
 * 
 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
 *  School of Computer Science
 *  Carnegie Mellon University
 *  Pittsburgh PA 15213-3890
 * 
 * any improvements or extensions that they make and grant Carnegie Mellon
 * the rights to redistribute these changes.
 */
/*
 */

/*
 *      kern/ipc_host.c
 *
 *      Routines to implement host ports.
 */
#include <mach/message.h>
#include <mach/mach_traps.h>
#include <mach/etap_events.h>
#include <mach/mach_host_server.h>
#include <kern/host.h>
#include <kern/processor.h>
#include <kern/lock.h>
#include <kern/task.h>
#include <kern/thread.h>
#include <kern/ipc_host.h>
#include <kern/ipc_kobject.h>
#include <kern/misc_protos.h>
#include <kern/spl.h>
#include <ipc/ipc_port.h>
#include <ipc/ipc_space.h>

/*
 * Forward declarations
 */

void
ipc_processor_terminate(
        processor_t     processor);

void
ipc_processor_disable(
        processor_t     processor);

boolean_t
ref_pset_port_locked(
        ipc_port_t port, boolean_t matchn, processor_set_t *ppset);

/*
 *      ipc_host_init: set up various things.
 */

void ipc_host_init(void)
{
        ipc_port_t      port;
        int i;

        mutex_init(&realhost.lock, ETAP_MISC_MASTER);

        /*
         *      Allocate and set up the two host ports.
         */
        port = ipc_port_alloc_kernel();
        if (port == IP_NULL)
                panic("ipc_host_init");

        ipc_kobject_set(port, (ipc_kobject_t) &realhost, IKOT_HOST);
        realhost.host_self = port;

        port = ipc_port_alloc_kernel();
        if (port == IP_NULL)
                panic("ipc_host_init");

        ipc_kobject_set(port, (ipc_kobject_t) &realhost, IKOT_HOST_PRIV);
        realhost.host_priv_self = port;

        port = ipc_port_alloc_kernel();
        if (port == IP_NULL)
                panic("ipc_host_init");

        ipc_kobject_set(port, (ipc_kobject_t) &realhost, IKOT_HOST_SECURITY);
        realhost.host_security_self = port;

        realhost.io_master = IP_NULL;

        for (i = FIRST_EXCEPTION; i < EXC_TYPES_COUNT; i++) {
                        realhost.exc_actions[i].port = IP_NULL;
                }/* for */

        /*
         *      Set up ipc for default processor set.
         */
        ipc_pset_init(&default_pset);
        ipc_pset_enable(&default_pset);

        /*
         *      And for master processor
         */
        ipc_processor_init(master_processor);
        ipc_processor_enable(master_processor);
}

/*
 *      Routine:        host_self_trap [mach trap]
 *      Purpose:
 *              Give the caller send rights for his own host port.
 *      Conditions:
 *              Nothing locked.
 *      Returns:
 *              MACH_PORT_NULL if there are any resource failures
 *              or other errors.
 */

mach_port_name_t
host_self_trap(void)
{
        ipc_port_t sright;

        sright = ipc_port_copy_send(current_task()->itk_host);
        return ipc_port_copyout_send(sright, current_space());
}

/*
 *      ipc_processor_init:
 *
 *      Initialize ipc access to processor by allocating port.
 */

void
ipc_processor_init(
        processor_t     processor)
{
        ipc_port_t      port;

        port = ipc_port_alloc_kernel();
        if (port == IP_NULL)
                panic("ipc_processor_init");
        processor->processor_self = port;
}

/*
 *      ipc_processor_enable:
 *
 *      Enable ipc control of processor by setting port object.
 */
void
ipc_processor_enable(
        processor_t     processor)
{
        ipc_port_t      myport;

        myport = processor->processor_self;
        ipc_kobject_set(myport, (ipc_kobject_t) processor, IKOT_PROCESSOR);
}

/*
 *      ipc_processor_disable:
 *
 *      Disable ipc control of processor by clearing port object.
 */
void
ipc_processor_disable(
        processor_t     processor)
{
        ipc_port_t      myport;

        myport = processor->processor_self;
        if (myport == IP_NULL)
                return;
        ipc_kobject_set(myport, IKO_NULL, IKOT_NONE);
}

/*
 *      ipc_processor_terminate:
 *
 *      Processor is off-line.  Destroy ipc control port.
 */
void
ipc_processor_terminate(
        processor_t     processor)
{
        ipc_port_t      myport;
        spl_t           s;

        s = splsched();
        processor_lock(processor);
        myport = processor->processor_self;
        if (myport == IP_NULL) {
                processor_unlock(processor);
                splx(s);
                return;
        }

        processor->processor_self = IP_NULL;
        processor_unlock(processor);
        splx(s);

        ipc_port_dealloc_kernel(myport);
}
        
/*
 *      ipc_pset_init:
 *
 *      Initialize ipc control of a processor set by allocating its ports.
 */

void
ipc_pset_init(
        processor_set_t         pset)
{
        ipc_port_t      port;

        port = ipc_port_alloc_kernel();
        if (port == IP_NULL)
                panic("ipc_pset_init");
        pset->pset_self = port;

        port = ipc_port_alloc_kernel();
        if (port == IP_NULL)
                panic("ipc_pset_init");
        pset->pset_name_self = port;
}

/*
 *      ipc_pset_enable:
 *
 *      Enable ipc access to a processor set.
 */
void
ipc_pset_enable(
        processor_set_t         pset)
{
        pset_lock(pset);
        if (pset->active) {
                ipc_kobject_set(pset->pset_self,
                                (ipc_kobject_t) pset, IKOT_PSET);
                ipc_kobject_set(pset->pset_name_self,
                                (ipc_kobject_t) pset, IKOT_PSET_NAME);
                pset->ref_count += 2;
        }
        pset_unlock(pset);
}

/*
 *      ipc_pset_disable:
 *
 *      Disable ipc access to a processor set by clearing the port objects.
 *      Caller must hold pset lock and a reference to the pset.  Ok to
 *      just decrement pset reference count as a result.
 */
void
ipc_pset_disable(
        processor_set_t         pset)
{
        ipc_kobject_set(pset->pset_self, IKO_NULL, IKOT_NONE);
        ipc_kobject_set(pset->pset_name_self, IKO_NULL, IKOT_NONE);
        pset->ref_count -= 2;
}

/*
 *      ipc_pset_terminate:
 *
 *      Processor set is dead.  Deallocate the ipc control structures.
 */
void
ipc_pset_terminate(
        processor_set_t         pset)
{
        ipc_port_dealloc_kernel(pset->pset_self);
        ipc_port_dealloc_kernel(pset->pset_name_self);
}

/*
 *      processor_set_default, processor_set_default_priv:
 *
 *      Return ports for manipulating default_processor set.  MiG code
 *      differentiates between these two routines.
 */
kern_return_t
processor_set_default(
        host_t                  host,
        processor_set_t         *pset)
{
        if (host == HOST_NULL)
                return(KERN_INVALID_ARGUMENT);

        *pset = &default_pset;
        pset_reference(*pset);
        return(KERN_SUCCESS);
}

/*
 *      Routine:        convert_port_to_host
 *      Purpose:
 *              Convert from a port to a host.
 *              Doesn't consume the port ref; the host produced may be null.
 *      Conditions:
 *              Nothing locked.
 */

host_t
convert_port_to_host(
        ipc_port_t      port)
{
        host_t host = HOST_NULL;

        if (IP_VALID(port)) {
                ip_lock(port);
                if (ip_active(port) &&
                    ((ip_kotype(port) == IKOT_HOST) ||
                     (ip_kotype(port) == IKOT_HOST_PRIV) 
                     ))
                        host = (host_t) port->ip_kobject;
                ip_unlock(port);
        }

        return host;
}

/*
 *      Routine:        convert_port_to_host_priv
 *      Purpose:
 *              Convert from a port to a host.
 *              Doesn't consume the port ref; the host produced may be null.
 *      Conditions:
 *              Nothing locked.
 */

host_t
convert_port_to_host_priv(
        ipc_port_t      port)
{
        host_t host = HOST_NULL;

        if (IP_VALID(port)) {
                ip_lock(port);
                if (ip_active(port) &&
                    (ip_kotype(port) == IKOT_HOST_PRIV))
                        host = (host_t) port->ip_kobject;
                ip_unlock(port);
        }

        return host;
}

/*
 *      Routine:        convert_port_to_processor
 *      Purpose:
 *              Convert from a port to a processor.
 *              Doesn't consume the port ref;
 *              the processor produced may be null.
 *      Conditions:
 *              Nothing locked.
 */

processor_t
convert_port_to_processor(
        ipc_port_t      port)
{
        processor_t processor = PROCESSOR_NULL;

        if (IP_VALID(port)) {
                ip_lock(port);
                if (ip_active(port) &&
                    (ip_kotype(port) == IKOT_PROCESSOR))
                        processor = (processor_t) port->ip_kobject;
                ip_unlock(port);
        }

        return processor;
}

/*
 *      Routine:        convert_port_to_pset
 *      Purpose:
 *              Convert from a port to a pset.
 *              Doesn't consume the port ref; produces a pset ref,
 *              which may be null.
 *      Conditions:
 *              Nothing locked.
 */

processor_set_t
convert_port_to_pset(
        ipc_port_t      port)
{
        boolean_t r;
        processor_set_t pset = PROCESSOR_SET_NULL;

        r = FALSE;
        while (!r && IP_VALID(port)) {
                ip_lock(port);
                r = ref_pset_port_locked(port, FALSE, &pset);
                /* port unlocked */
        }
        return pset;
}

/*
 *      Routine:        convert_port_to_pset_name
 *      Purpose:
 *              Convert from a port to a pset.
 *              Doesn't consume the port ref; produces a pset ref,
 *              which may be null.
 *      Conditions:
 *              Nothing locked.
 */

processor_set_name_t
convert_port_to_pset_name(
        ipc_port_t      port)
{
        boolean_t r;
        processor_set_t pset = PROCESSOR_SET_NULL;

        r = FALSE;
        while (!r && IP_VALID(port)) {
                ip_lock(port);
                r = ref_pset_port_locked(port, TRUE, &pset);
                /* port unlocked */
        }
        return pset;
}

boolean_t
ref_pset_port_locked(ipc_port_t port, boolean_t matchn, processor_set_t *ppset)
{
        processor_set_t pset;

        pset = PROCESSOR_SET_NULL;
        if (ip_active(port) &&
                ((ip_kotype(port) == IKOT_PSET) ||
                 (matchn && (ip_kotype(port) == IKOT_PSET_NAME)))) {
                pset = (processor_set_t) port->ip_kobject;
                if (!pset_lock_try(pset)) {
                        ip_unlock(port);
                        mutex_pause();
                        return (FALSE);
                }
                pset->ref_count++;
                pset_unlock(pset);
        }
        *ppset = pset;
        ip_unlock(port);
        return (TRUE);
}

/*
 *      Routine:        convert_host_to_port
 *      Purpose:
 *              Convert from a host to a port.
 *              Produces a naked send right which may be invalid.
 *      Conditions:
 *              Nothing locked.
 */

ipc_port_t
convert_host_to_port(
        host_t          host)
{
        ipc_port_t port;

        port = ipc_port_make_send(host->host_self);

        return port;
}

/*
 *      Routine:        convert_processor_to_port
 *      Purpose:
 *              Convert from a processor to a port.
 *              Produces a naked send right which may be invalid.
 *      Conditions:
 *              Nothing locked.
 */

ipc_port_t
convert_processor_to_port(
        processor_t             processor)
{
        ipc_port_t port;
        spl_t   s;

        s = splsched();
        processor_lock(processor);

        if (processor->processor_self != IP_NULL)
                port = ipc_port_make_send(processor->processor_self);
        else
                port = IP_NULL;

        processor_unlock(processor);
        splx(s);

        return port;
}

/*
 *      Routine:        convert_pset_to_port
 *      Purpose:
 *              Convert from a pset to a port.
 *              Consumes a pset ref; produces a naked send right
 *              which may be invalid.
 *      Conditions:
 *              Nothing locked.
 */

ipc_port_t
convert_pset_to_port(
        processor_set_t         pset)
{
        ipc_port_t port;

        pset_lock(pset);
        if (pset->active)
                port = ipc_port_make_send(pset->pset_self);
        else
                port = IP_NULL;
        pset_unlock(pset);

        pset_deallocate(pset);
        return port;
}

/*
 *      Routine:        convert_pset_name_to_port
 *      Purpose:
 *              Convert from a pset to a port.
 *              Consumes a pset ref; produces a naked send right
 *              which may be invalid.
 *      Conditions:
 *              Nothing locked.
 */

ipc_port_t
convert_pset_name_to_port(
        processor_set_name_t            pset)
{
        ipc_port_t port;

        pset_lock(pset);
        if (pset->active)
                port = ipc_port_make_send(pset->pset_name_self);
        else
                port = IP_NULL;
        pset_unlock(pset);

        pset_deallocate(pset);
        return port;
}

/*
 *      Routine:        convert_port_to_host_security
 *      Purpose:
 *              Convert from a port to a host security.
 *              Doesn't consume the port ref; the port produced may be null.
 *      Conditions:
 *              Nothing locked.
 */

host_t
convert_port_to_host_security(
        ipc_port_t port)
{
        host_t host = HOST_NULL;

        if (IP_VALID(port)) {
                ip_lock(port);
                if (ip_active(port) &&
                    (ip_kotype(port) == IKOT_HOST_SECURITY))
                        host = (host_t) port->ip_kobject;
                ip_unlock(port);
        }

        return host;
}

/*
 *      Routine:        host_set_exception_ports [kernel call]
 *      Purpose:
 *                      Sets the host exception port, flavor and
 *                      behavior for the exception types specified by the mask.
 *                      There will be one send right per exception per valid
 *                      port.
 *      Conditions:
 *              Nothing locked.  If successful, consumes
 *              the supplied send right.
 *      Returns:
 *              KERN_SUCCESS            Changed the special port.
 *              KERN_INVALID_ARGUMENT   The host_priv is not valid,
 *                                      Illegal mask bit set.
 *                                      Illegal exception behavior
 */
kern_return_t
host_set_exception_ports(
        host_priv_t                             host_priv,
        exception_mask_t                exception_mask,
        ipc_port_t                      new_port,
        exception_behavior_t            new_behavior,
        thread_state_flavor_t           new_flavor)
{
        register int    i;
        ipc_port_t      old_port[EXC_TYPES_COUNT];

        if (host_priv == HOST_PRIV_NULL) {
                return KERN_INVALID_ARGUMENT;
        }

        assert(host_priv == &realhost);

        if (exception_mask & ~EXC_MASK_ALL) {
                return KERN_INVALID_ARGUMENT;
        }

        if (IP_VALID(new_port)) {
                switch (new_behavior) {
                case EXCEPTION_DEFAULT:
                case EXCEPTION_STATE:
                case EXCEPTION_STATE_IDENTITY:
                        break;
                default:
                        return KERN_INVALID_ARGUMENT;
                }
        }
        /* Cannot easily check "new_flavor", but that just means that
         * the flavor in the generated exception message might be garbage:
         * GIGO
         */
        host_lock(host_priv);

        for (i = FIRST_EXCEPTION; i < EXC_TYPES_COUNT; i++) {
                if (exception_mask & (1 << i)) {
                        old_port[i] = host_priv->exc_actions[i].port;
                        host_priv->exc_actions[i].port =
                                ipc_port_copy_send(new_port);
                        host_priv->exc_actions[i].behavior = new_behavior;
                        host_priv->exc_actions[i].flavor = new_flavor;
                } else
                        old_port[i] = IP_NULL;
        }/* for */

        /*
         * Consume send rights without any lock held.
         */
        host_unlock(host_priv);
        for (i = FIRST_EXCEPTION; i < EXC_TYPES_COUNT; i++)
                if (IP_VALID(old_port[i]))
                        ipc_port_release_send(old_port[i]);
        if (IP_VALID(new_port))          /* consume send right */
                ipc_port_release_send(new_port);

        return KERN_SUCCESS;
}

/*
 *      Routine:        host_get_exception_ports [kernel call]
 *      Purpose:
 *              Clones a send right for each of the host's exception
 *              ports specified in the mask and returns the behaviour
 *              and flavor of said port.
 *
 *              Returns upto [in} CountCnt elements.
 *
 *      Conditions:
 *              Nothing locked.
 *      Returns:
 *              KERN_SUCCESS            Extracted a send right.
 *              KERN_INVALID_ARGUMENT   Invalid host_priv specified,
 *                                      Invalid special port,
 *                                      Illegal mask bit set.
 *              KERN_FAILURE            The thread is dead.
 */
kern_return_t
host_get_exception_ports(
        host_priv_t                     host_priv,
        exception_mask_t                exception_mask,
        exception_mask_array_t          masks,
        mach_msg_type_number_t          * CountCnt,
        exception_port_array_t          ports,
        exception_behavior_array_t      behaviors,
        thread_state_flavor_array_t     flavors         )
{
        register int    i,
                        j,
                        count;

        if (host_priv == HOST_PRIV_NULL)
                return KERN_INVALID_ARGUMENT;

        if (exception_mask & ~EXC_MASK_ALL) {
                return KERN_INVALID_ARGUMENT;
        }

        assert (host_priv == &realhost);

        host_lock(host_priv);

        count = 0;

        for (i = FIRST_EXCEPTION; i < EXC_TYPES_COUNT; i++) {
                if (exception_mask & (1 << i)) {
                        for (j = 0; j < count; j++) {
/*
 *                              search for an identical entry, if found
 *                              set corresponding mask for this exception.
 */
                                if (host_priv->exc_actions[i].port == ports[j] &&
                                        host_priv->exc_actions[i].behavior == behaviors[j]
                                  && host_priv->exc_actions[i].flavor == flavors[j])
                                {
                                        masks[j] |= (1 << i);
                                        break;
                                }
                        }/* for */
                        if (j == count) {
                                masks[j] = (1 << i);
                                ports[j] =
                                  ipc_port_copy_send(host_priv->exc_actions[i].port);
                                behaviors[j] = host_priv->exc_actions[i].behavior;
                                flavors[j] = host_priv->exc_actions[i].flavor;
                                count++;
                                if (count > *CountCnt) {
                                        break;
                                }
                        }
                }
        }/* for */
        host_unlock(host_priv);

        *CountCnt = count;
        return KERN_SUCCESS;
}

kern_return_t
host_swap_exception_ports(
        host_priv_t                             host_priv,
        exception_mask_t                exception_mask,
        ipc_port_t                      new_port,
        exception_behavior_t            new_behavior,
        thread_state_flavor_t           new_flavor,
        exception_mask_array_t          masks,
        mach_msg_type_number_t          * CountCnt,
        exception_port_array_t          ports,
        exception_behavior_array_t      behaviors,
        thread_state_flavor_array_t     flavors         )
{
        register int    i,
                        j,
                        count;
        ipc_port_t      old_port[EXC_TYPES_COUNT];

        if (host_priv == HOST_PRIV_NULL)
                return KERN_INVALID_ARGUMENT;

        if (exception_mask & ~EXC_MASK_ALL) {
                return KERN_INVALID_ARGUMENT;
        }

        if (IP_VALID(new_port)) {
                switch (new_behavior) {
                case EXCEPTION_DEFAULT:
                case EXCEPTION_STATE:
                case EXCEPTION_STATE_IDENTITY:
                        break;
                default:
                        return KERN_INVALID_ARGUMENT;
                }
        }
        /* Cannot easily check "new_flavor", but that just means that
         * the flavor in the generated exception message might be garbage:
         * GIGO */

        host_lock(host_priv);

        count = 0;

        for (i = FIRST_EXCEPTION; i < EXC_TYPES_COUNT; i++) {
                if (exception_mask & (1 << i)) {
                        for (j = 0; j < count; j++) {
/*
 *                              search for an identical entry, if found
 *                              set corresponding mask for this exception.
 */
                                if (host_priv->exc_actions[i].port == ports[j] &&
                                  host_priv->exc_actions[i].behavior == behaviors[j]
                                  && host_priv->exc_actions[i].flavor == flavors[j])
                                {
                                        masks[j] |= (1 << i);
                                        break;
                                }
                        }/* for */
                        if (j == count) {
                                masks[j] = (1 << i);
                                ports[j] =
                                ipc_port_copy_send(host_priv->exc_actions[i].port);
                                behaviors[j] = host_priv->exc_actions[i].behavior;
                                flavors[j] = host_priv->exc_actions[i].flavor;
                                count++;
                        }
                        old_port[i] = host_priv->exc_actions[i].port;
                        host_priv->exc_actions[i].port =
                                ipc_port_copy_send(new_port);
                        host_priv->exc_actions[i].behavior = new_behavior;
                        host_priv->exc_actions[i].flavor = new_flavor;
                        if (count > *CountCnt) {
                                break;
                        }
                } else
                        old_port[i] = IP_NULL;
        }/* for */
        host_unlock(host_priv);

        /*
         * Consume send rights without any lock held.
         */
        for (i = FIRST_EXCEPTION; i < EXC_TYPES_COUNT; i++)
                if (IP_VALID(old_port[i]))
                        ipc_port_release_send(old_port[i]);
        if (IP_VALID(new_port))          /* consume send right */
                ipc_port_release_send(new_port);
        *CountCnt = count;

        return KERN_SUCCESS;
}