]> git.saurik.com Git - apple/xnu.git/blobdiff - osfmk/ipc/ipc_kmsg.c
xnu-792.6.22.tar.gz
[apple/xnu.git] / osfmk / ipc / ipc_kmsg.c
index 58a91459339e668fd5dcbe38bc8f58f6f519007d..2edc405596e4eb3551388f95fb03eb75977a4e52 100644 (file)
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2000-2005 Apple Computer, Inc. All rights reserved.
  *
  * @APPLE_LICENSE_HEADER_START@
  * 
  *     Operations on kernel messages.
  */
 
-#include <cpus.h>
 #include <norma_vm.h>
 
+#include <mach/mach_types.h>
 #include <mach/boolean.h>
 #include <mach/kern_return.h>
 #include <mach/message.h>
 #include <mach/port.h>
+#include <mach/vm_map.h>
+#include <mach/mach_vm.h>
 #include <mach/vm_statistics.h>
+
+#include <kern/kern_types.h>
 #include <kern/assert.h>
+#include <kern/ipc_kobject.h>
 #include <kern/kalloc.h>
+#include <kern/zalloc.h>
+#include <kern/processor.h>
 #include <kern/thread.h>
 #include <kern/sched_prim.h>
 #include <kern/spl.h>
 #include <kern/misc_protos.h>
 #include <kern/counters.h>
+#include <kern/cpu_data.h>
+
 #include <vm/vm_map.h>
 #include <vm/vm_object.h>
 #include <vm/vm_kern.h>
+
 #include <ipc/port.h>
+#include <ipc/ipc_types.h>
 #include <ipc/ipc_entry.h>
 #include <ipc/ipc_kmsg.h>
 #include <ipc/ipc_notify.h>
 
 #include <string.h>
 
+#ifdef ppc
+#include <ppc/Firmware.h>
+#include <ppc/low_trace.h>
+#endif
+
+
 extern vm_map_t                ipc_kernel_copy_map;
 extern vm_size_t       ipc_kmsg_max_vm_space;
 extern vm_size_t       msg_ool_size_small;
 
 #define MSG_OOL_SIZE_SMALL     msg_ool_size_small
 
+#if defined(__LP64__)
+#define MAP_SIZE_DIFFERS(map)  (map->max_offset < MACH_VM_MAX_ADDRESS)
+#define OTHER_OOL_DESCRIPTOR   mach_msg_ool_descriptor32_t
+#define OTHER_OOL_PORTS_DESCRIPTOR     mach_msg_ool_ports_descriptor32_t
+#else
+#define MAP_SIZE_DIFFERS(map)  (map->max_offset > VM_MAX_ADDRESS)
+#define OTHER_OOL_DESCRIPTOR   mach_msg_ool_descriptor64_t
+#define OTHER_OOL_PORTS_DESCRIPTOR     mach_msg_ool_ports_descriptor64_t
+#endif
+
+#define DESC_SIZE_ADJUSTMENT   (sizeof(OTHER_OOL_DESCRIPTOR) - \
+                                sizeof(mach_msg_ool_descriptor_t))
+
+/* scatter list macros */
+
+#define SKIP_PORT_DESCRIPTORS(s, c)                                    \
+MACRO_BEGIN                                                            \
+       if ((s) != MACH_MSG_DESCRIPTOR_NULL) {                          \
+               while ((c) > 0) {                                       \
+                       if ((s)->type.type != MACH_MSG_PORT_DESCRIPTOR) \
+                               break;                                  \
+                       (s)++; (c)--;                                   \
+               }                                                       \
+               if (c == 0)                                             \
+                       (s) = MACH_MSG_DESCRIPTOR_NULL;                 \
+       }                                                               \
+MACRO_END
+
+#define INCREMENT_SCATTER(s, c, d)                                     \
+MACRO_BEGIN                                                            \
+       if ((s) != MACH_MSG_DESCRIPTOR_NULL) {                          \
+           s = (d) ? (mach_msg_descriptor_t *)                         \
+               ((OTHER_OOL_DESCRIPTOR *)(s) + 1) :                     \
+               (s + 1);                                                \
+               (c)--;                                                  \
+       }                                                               \
+MACRO_END
+
+/* zone for cached ipc_kmsg_t structures */
+zone_t                 ipc_kmsg_zone;
 
 /*
  * Forward declarations
@@ -104,26 +161,21 @@ void ipc_kmsg_clean(
 
 void ipc_kmsg_clean_body(
        ipc_kmsg_t      kmsg,
-       mach_msg_type_number_t  number);
+       mach_msg_type_number_t  number,
+       mach_msg_descriptor_t   *desc);
 
 void ipc_kmsg_clean_partial(
        ipc_kmsg_t              kmsg,
        mach_msg_type_number_t  number,
+       mach_msg_descriptor_t   *desc,
        vm_offset_t             paddr,
        vm_size_t               length);
 
-mach_msg_return_t ipc_kmsg_copyout_body(
-       ipc_kmsg_t              kmsg,
-       ipc_space_t             space,
-       vm_map_t                map,
-       mach_msg_body_t         *slist);
-
 mach_msg_return_t ipc_kmsg_copyin_body(
        ipc_kmsg_t              kmsg,
        ipc_space_t             space,
        vm_map_t                map);
 
-void ikm_cache_init(void);
 /*
  *     We keep a per-processor cache of kernel message buffers.
  *     The cache saves the overhead/locking of using kalloc/kfree.
@@ -131,35 +183,6 @@ void ikm_cache_init(void);
  *     and it also uses less memory.  Access to the cache doesn't
  *     require locking.
  */
-#define IKM_STASH 16   /* # of cache entries per cpu */
-ipc_kmsg_t     ipc_kmsg_cache[ NCPUS ][ IKM_STASH ];
-unsigned int   ipc_kmsg_cache_avail[NCPUS];
-
-/*
- *     Routine:        ipc_kmsg_init
- *     Purpose:
- *             Initialize the kmsg system.  For each CPU, we need to
- *             pre-stuff the kmsg cache.
- */
-void
-ipc_kmsg_init()
-{
-       unsigned int    cpu, i;
-
-       for (cpu = 0; cpu < NCPUS; ++cpu) {
-               for (i = 0; i < IKM_STASH; ++i) {
-                       ipc_kmsg_t kmsg;
-
-                       kmsg = (ipc_kmsg_t)
-                              kalloc(ikm_plus_overhead(IKM_SAVED_MSG_SIZE));
-                       if (kmsg == IKM_NULL)
-                               panic("ipc_kmsg_init");
-                       ikm_init(kmsg, IKM_SAVED_MSG_SIZE);
-                       ipc_kmsg_cache[cpu][i] = kmsg;
-               }
-               ipc_kmsg_cache_avail[cpu] = IKM_STASH;
-       }
-}
 
 /*
  *     Routine:        ipc_kmsg_alloc
@@ -173,31 +196,70 @@ ipc_kmsg_t
 ipc_kmsg_alloc(
        mach_msg_size_t msg_and_trailer_size)
 {
+       mach_msg_size_t max_expanded_size;
        ipc_kmsg_t kmsg;
 
-       if ((msg_and_trailer_size <= IKM_SAVED_MSG_SIZE)) {
-               unsigned int    cpu, i;
+#if !defined(__LP64__)
+       mach_msg_size_t size = msg_and_trailer_size - MAX_TRAILER_SIZE;
+
+       /*
+        * LP64support -
+        * Pad the allocation in case we need to expand the
+        * message descrptors for user spaces with pointers larger than
+        * the kernel's own.  We don't know how many descriptors
+        * there are yet, so just assume the whole body could be
+        * descriptors (if there could be any at all).
+        *
+        * The expansion space is left in front of the header,
+        * because it is easier to pull the header and descriptors
+        * forward as we process them than it is to push all the
+        * data backwards.
+        */
+       max_expanded_size = 
+               (size > sizeof(mach_msg_base_t)) ?
+               (msg_and_trailer_size + DESC_SIZE_ADJUSTMENT * 
+                ((size - sizeof(mach_msg_base_t)) /
+                 (sizeof(mach_msg_ool_descriptor_t))))
+               :
+               (msg_and_trailer_size);
+#else
+       max_expanded_size = msg_and_trailer_size;
+#endif
+
+       /* round up for ikm_cache */
+       if (max_expanded_size < IKM_SAVED_MSG_SIZE)
+               max_expanded_size = IKM_SAVED_MSG_SIZE;
+
+       if (max_expanded_size == IKM_SAVED_MSG_SIZE) {
+               struct ikm_cache        *cache;
+               unsigned int            i;
 
                disable_preemption();
-               cpu = cpu_number();
-               if ((i = ipc_kmsg_cache_avail[cpu]) > 0) {
+               cache = &PROCESSOR_DATA(current_processor(), ikm_cache);
+               if ((i = cache->avail) > 0) {
                        assert(i <= IKM_STASH);
-                       kmsg = ipc_kmsg_cache[cpu][--i];
-                       ipc_kmsg_cache_avail[cpu] = i;
-                       ikm_check_init(kmsg, IKM_SAVED_MSG_SIZE);
+                       kmsg = cache->entries[--i];
+                       cache->avail = i;
+                       ikm_check_init(kmsg, max_expanded_size);
                        enable_preemption();
+                       kmsg->ikm_header = (mach_msg_header_t *)
+                                          ((vm_offset_t)(kmsg + 1) +
+                                           max_expanded_size -
+                                           msg_and_trailer_size);
                        return (kmsg);
                }
                enable_preemption();
+               kmsg = (ipc_kmsg_t)zalloc(ipc_kmsg_zone);
+       } else {
+               kmsg = (ipc_kmsg_t)kalloc(ikm_plus_overhead(max_expanded_size));
        }
 
-       /* round up for ikm_cache */
-       if (msg_and_trailer_size < IKM_SAVED_MSG_SIZE)
-           msg_and_trailer_size = IKM_SAVED_MSG_SIZE;
-
-       kmsg = (ipc_kmsg_t)kalloc(ikm_plus_overhead(msg_and_trailer_size));
        if (kmsg != IKM_NULL) {
-               ikm_init(kmsg, msg_and_trailer_size);
+               ikm_init(kmsg, max_expanded_size);
+               kmsg->ikm_header = (mach_msg_header_t *)
+                                  ((vm_offset_t)(kmsg + 1) +
+                                   max_expanded_size -
+                                   msg_and_trailer_size);
        }
        return(kmsg);
 }
@@ -224,8 +286,7 @@ ipc_kmsg_free(
        /*
         * Check to see if the message is bound to the port.  If so,
         * mark it not in use.  If the port isn't already dead, then
-        * leave the message associated with it.  Otherwise, free it
-        * (not to the cache).
+        * leave the message associated with it.  Otherwise, free it.
         */
        port = ikm_prealloc_inuse_port(kmsg);
        if (port != IP_NULL) {
@@ -237,32 +298,28 @@ ipc_kmsg_free(
                        return;
                }
                ip_check_unlock(port);  /* May be last reference */
-               goto free_it;
        }
 
        /*
         * Peek and see if it has to go back in the cache.
         */
-       if (kmsg->ikm_size == IKM_SAVED_MSG_SIZE &&
-           ipc_kmsg_cache_avail[cpu_number()] < IKM_STASH) {
-               unsigned int cpu, i;
+       if (kmsg->ikm_size == IKM_SAVED_MSG_SIZE) {
+               struct ikm_cache        *cache;
+               unsigned int            i;
 
                disable_preemption();
-               cpu = cpu_number();
-
-               i = ipc_kmsg_cache_avail[cpu];
-               if (i < IKM_STASH) {
-                       assert(i >= 0);
-                       ipc_kmsg_cache[cpu][i] = kmsg;
-                       ipc_kmsg_cache_avail[cpu] = i + 1;
+               cache = &PROCESSOR_DATA(current_processor(), ikm_cache);
+               if ((i = cache->avail) < IKM_STASH) {
+                       cache->entries[i] = kmsg;
+                       cache->avail = i + 1;
                        enable_preemption();
                        return;
                }
                enable_preemption();
+               zfree(ipc_kmsg_zone, kmsg);
+               return;
        }
-
- free_it:
-       kfree((vm_offset_t) kmsg, ikm_plus_overhead(size));
+       kfree(kmsg, ikm_plus_overhead(size));
 }
 
 
@@ -406,16 +463,16 @@ ipc_kmsg_destroy(
  *     Conditions:
  *             No locks held.
  */
-
+void
 ipc_kmsg_destroy_dest(
        ipc_kmsg_t kmsg)
 {
     ipc_port_t port;
        
-    port = kmsg->ikm_header.msgh_remote_port;
+    port = kmsg->ikm_header->msgh_remote_port;
 
     ipc_port_release(port);
-    kmsg->ikm_header.msgh_remote_port = MACH_PORT_NULL;
+    kmsg->ikm_header->msgh_remote_port = MACH_PORT_NULL;
     ipc_kmsg_destroy(kmsg);
 }
 
@@ -431,16 +488,15 @@ ipc_kmsg_destroy_dest(
 
 void
 ipc_kmsg_clean_body(
-       ipc_kmsg_t      kmsg,
-       mach_msg_type_number_t  number)
+       __unused ipc_kmsg_t     kmsg,
+       mach_msg_type_number_t  number,
+       mach_msg_descriptor_t   *saddr)
 {
-    mach_msg_descriptor_t      *saddr, *eaddr;
+    mach_msg_descriptor_t      *eaddr;
 
     if ( number == 0 )
        return;
 
-    saddr = (mach_msg_descriptor_t *) 
-                       ((mach_msg_base_t *) &kmsg->ikm_header + 1);
     eaddr = saddr + number;
 
     for ( ; saddr < eaddr; saddr++ ) {
@@ -505,7 +561,7 @@ ipc_kmsg_clean_body(
 
                assert(dsc->count != 0);
 
-               kfree((vm_offset_t) dsc->address, 
+               kfree(dsc->address, 
                     (vm_size_t) dsc->count * sizeof(mach_port_name_t));
                break;
            }
@@ -533,17 +589,18 @@ void
 ipc_kmsg_clean_partial(
        ipc_kmsg_t              kmsg,
        mach_msg_type_number_t  number,
+       mach_msg_descriptor_t   *desc,
        vm_offset_t             paddr,
        vm_size_t               length)
 {
        ipc_object_t object;
-       mach_msg_bits_t mbits = kmsg->ikm_header.msgh_bits;
+       mach_msg_bits_t mbits = kmsg->ikm_header->msgh_bits;
 
-       object = (ipc_object_t) kmsg->ikm_header.msgh_remote_port;
+       object = (ipc_object_t) kmsg->ikm_header->msgh_remote_port;
        assert(IO_VALID(object));
        ipc_object_destroy(object, MACH_MSGH_BITS_REMOTE(mbits));
 
-       object = (ipc_object_t) kmsg->ikm_header.msgh_local_port;
+       object = (ipc_object_t) kmsg->ikm_header->msgh_local_port;
        if (IO_VALID(object))
                ipc_object_destroy(object, MACH_MSGH_BITS_LOCAL(mbits));
 
@@ -551,7 +608,7 @@ ipc_kmsg_clean_partial(
                (void) vm_deallocate(ipc_kernel_copy_map, paddr, length);
        }
 
-       ipc_kmsg_clean_body(kmsg, number);
+       ipc_kmsg_clean_body(kmsg, number, desc);
 }
 
 /*
@@ -570,20 +627,21 @@ ipc_kmsg_clean(
        ipc_object_t object;
        mach_msg_bits_t mbits;
 
-       mbits = kmsg->ikm_header.msgh_bits;
-       object = (ipc_object_t) kmsg->ikm_header.msgh_remote_port;
+       mbits = kmsg->ikm_header->msgh_bits;
+       object = (ipc_object_t) kmsg->ikm_header->msgh_remote_port;
        if (IO_VALID(object))
                ipc_object_destroy(object, MACH_MSGH_BITS_REMOTE(mbits));
 
-       object = (ipc_object_t) kmsg->ikm_header.msgh_local_port;
+       object = (ipc_object_t) kmsg->ikm_header->msgh_local_port;
        if (IO_VALID(object))
                ipc_object_destroy(object, MACH_MSGH_BITS_LOCAL(mbits));
 
        if (mbits & MACH_MSGH_BITS_COMPLEX) {
                mach_msg_body_t *body;
 
-               body = (mach_msg_body_t *) (&kmsg->ikm_header + 1);
-               ipc_kmsg_clean_body(kmsg, body->msgh_descriptor_count);
+               body = (mach_msg_body_t *) (kmsg->ikm_header + 1);
+               ipc_kmsg_clean_body(kmsg, body->msgh_descriptor_count,
+                                   (mach_msg_descriptor_t *)(body + 1));
        }
 }
 
@@ -624,6 +682,8 @@ ipc_kmsg_clear_prealloc(
        IP_CLEAR_PREALLOC(port, kmsg);
 }
 
+
+
 /*
  *     Routine:        ipc_kmsg_get
  *     Purpose:
@@ -641,16 +701,13 @@ ipc_kmsg_clear_prealloc(
 
 mach_msg_return_t
 ipc_kmsg_get(
-       mach_msg_header_t       *msg,
-       mach_msg_size_t         size,
+       mach_vm_address_t       msg_addr,
+       mach_msg_size_t size,
        ipc_kmsg_t              *kmsgp)
 {
        mach_msg_size_t                 msg_and_trailer_size;
        ipc_kmsg_t                      kmsg;
-       mach_msg_format_0_trailer_t     *trailer;
-       mach_port_name_t                dest_name;
-       ipc_entry_t                     dest_entry;
-       ipc_port_t                      dest_port;
+       mach_msg_max_trailer_t          *trailer;
 
        if ((size < sizeof(mach_msg_header_t)) || (size & 3))
                return MACH_SEND_MSG_TOO_SMALL;
@@ -662,12 +719,12 @@ ipc_kmsg_get(
        if (kmsg == IKM_NULL)
                return MACH_SEND_NO_BUFFER;
 
-       if (copyinmsg((char *) msg, (char *) &kmsg->ikm_header, size)) {
+       if (copyinmsg(msg_addr, (char *) kmsg->ikm_header, size)) {
                ipc_kmsg_free(kmsg);
                return MACH_SEND_INVALID_DATA;
        }
 
-       kmsg->ikm_header.msgh_size = size;
+       kmsg->ikm_header->msgh_size = size;
 
        /* 
         * I reserve for the trailer the largest space (MAX_TRAILER_SIZE)
@@ -675,11 +732,17 @@ ipc_kmsg_get(
         * is initialized to the minimum (sizeof(mach_msg_trailer_t)), to optimize
         * the cases where no implicit data is requested.
         */
-       trailer = (mach_msg_format_0_trailer_t *) ((vm_offset_t)&kmsg->ikm_header + size);
-       trailer->msgh_sender = current_thread()->top_act->task->sec_token;
+       trailer = (mach_msg_max_trailer_t *) ((vm_offset_t)kmsg->ikm_header + size);
+       trailer->msgh_sender = current_thread()->task->sec_token;
+       trailer->msgh_audit = current_thread()->task->audit_token;
        trailer->msgh_trailer_type = MACH_MSG_TRAILER_FORMAT_0;
        trailer->msgh_trailer_size = MACH_MSG_TRAILER_MINIMUM_SIZE;
-
+       
+#ifdef ppc
+       if(trcWork.traceMask) dbgTrace(0x1100, (unsigned int)kmsg->ikm_header->msgh_id, 
+               (unsigned int)kmsg->ikm_header->msgh_remote_port, 
+               (unsigned int)kmsg->ikm_header->msgh_local_port, 0); 
+#endif
        *kmsgp = kmsg;
        return MACH_MSG_SUCCESS;
 }
@@ -687,7 +750,9 @@ ipc_kmsg_get(
 /*
  *     Routine:        ipc_kmsg_get_from_kernel
  *     Purpose:
- *             Allocates a kernel message buffer.
+ *             First checks for a preallocated message
+ *             reserved for kernel clients.  If not found -
+ *             allocates a new kernel message buffer.
  *             Copies a kernel message to the message buffer.
  *             Only resource errors are allowed.
  *     Conditions:
@@ -701,16 +766,16 @@ ipc_kmsg_get(
 mach_msg_return_t
 ipc_kmsg_get_from_kernel(
        mach_msg_header_t       *msg,
-       mach_msg_size_t         size,
+       mach_msg_size_t size,
        ipc_kmsg_t              *kmsgp)
 {
        ipc_kmsg_t      kmsg;
        mach_msg_size_t msg_and_trailer_size;
-       mach_msg_format_0_trailer_t *trailer;
+       mach_msg_max_trailer_t *trailer;
        ipc_port_t      dest_port;
 
        assert(size >= sizeof(mach_msg_header_t));
-       assert((size & 3) == 0);
+//     assert((size & 3) == 0);
 
        assert(IP_VALID((ipc_port_t) msg->msgh_remote_port));
        dest_port = (ipc_port_t)msg->msgh_remote_port;
@@ -746,9 +811,9 @@ ipc_kmsg_get_from_kernel(
                        return MACH_SEND_NO_BUFFER;
        }
 
-       (void) memcpy((void *) &kmsg->ikm_header, (const void *) msg, size);
+       (void) memcpy((void *) kmsg->ikm_header, (const void *) msg, size);
 
-       kmsg->ikm_header.msgh_size = size;
+       kmsg->ikm_header->msgh_size = size;
 
        /* 
         * I reserve for the trailer the largest space (MAX_TRAILER_SIZE)
@@ -756,9 +821,10 @@ ipc_kmsg_get_from_kernel(
         * is initialized to the minimum (sizeof(mach_msg_trailer_t)), to
         * optimize the cases where no implicit data is requested.
         */
-       trailer = (mach_msg_format_0_trailer_t *) 
-                 ((vm_offset_t)&kmsg->ikm_header + size);
+       trailer = (mach_msg_max_trailer_t *) 
+                 ((vm_offset_t)kmsg->ikm_header + size);
        trailer->msgh_sender = KERNEL_SECURITY_TOKEN;
+       trailer->msgh_audit = KERNEL_AUDIT_TOKEN;
        trailer->msgh_trailer_type = MACH_MSG_TRAILER_FORMAT_0;
        trailer->msgh_trailer_size = MACH_MSG_TRAILER_MINIMUM_SIZE;
 
@@ -787,12 +853,11 @@ mach_msg_return_t
 ipc_kmsg_send(
        ipc_kmsg_t              kmsg,
        mach_msg_option_t       option,
-       mach_msg_timeout_t      timeout)
+       mach_msg_timeout_t      send_timeout)
 {
-       kern_return_t           save_wait_result;
-
        ipc_port_t port;
-       port = (ipc_port_t) kmsg->ikm_header.msgh_remote_port;
+
+       port = (ipc_port_t) kmsg->ikm_header->msgh_remote_port;
        assert(IP_VALID(port));
 
        ip_lock(port);
@@ -818,7 +883,7 @@ ipc_kmsg_send(
                if (kmsg == IKM_NULL)
                        return MACH_MSG_SUCCESS;
 
-               port = (ipc_port_t) kmsg->ikm_header.msgh_remote_port;
+               port = (ipc_port_t) kmsg->ikm_header->msgh_remote_port;
                assert(IP_VALID(port));
                ip_lock(port);
                /* fall thru with reply - same options */
@@ -839,12 +904,12 @@ ipc_kmsg_send(
 
                ip_release(port);
                ip_check_unlock(port);
-               kmsg->ikm_header.msgh_remote_port = MACH_PORT_NULL;
+               kmsg->ikm_header->msgh_remote_port = MACH_PORT_NULL;
                ipc_kmsg_destroy(kmsg);
                return MACH_MSG_SUCCESS;
        }
 
-       if (kmsg->ikm_header.msgh_bits & MACH_MSGH_BITS_CIRCULAR) {
+       if (kmsg->ikm_header->msgh_bits & MACH_MSGH_BITS_CIRCULAR) {
                ip_unlock(port);
 
                /* don't allow the creation of a circular loop */
@@ -859,7 +924,7 @@ ipc_kmsg_send(
         * queue.
         */
        ip_unlock(port);
-       return (ipc_mqueue_send(&port->ip_messages, kmsg, option, timeout));
+       return (ipc_mqueue_send(&port->ip_messages, kmsg, option, send_timeout));
 }
 
 /*
@@ -878,13 +943,13 @@ ipc_kmsg_send(
 
 mach_msg_return_t
 ipc_kmsg_put(
-       mach_msg_header_t       *msg,
+       mach_vm_address_t       msg_addr,
        ipc_kmsg_t              kmsg,
        mach_msg_size_t         size)
 {
        mach_msg_return_t mr;
 
-       if (copyoutmsg((const char *) &kmsg->ikm_header, (char *) msg, size))
+       if (copyoutmsg((const char *) kmsg->ikm_header, msg_addr, size))
                mr = MACH_RCV_INVALID_DATA;
        else
                mr = MACH_MSG_SUCCESS;
@@ -909,7 +974,7 @@ ipc_kmsg_put_to_kernel(
        ipc_kmsg_t              kmsg,
        mach_msg_size_t         size)
 {
-       (void) memcpy((void *) msg, (const void *) &kmsg->ikm_header, size);
+       (void) memcpy((void *) msg, (const void *) kmsg->ikm_header, size);
 
        ipc_kmsg_free(kmsg);
 }
@@ -997,7 +1062,8 @@ ipc_kmsg_copyin_header(
                }
 
                notify_port = (ipc_port_t) entry->ie_object;
-       }
+       } else
+               notify_port = IP_NULL;
 
        if (dest_name == reply_name) {
                ipc_entry_t entry;
@@ -1182,7 +1248,6 @@ ipc_kmsg_copyin_header(
                reply_soright = IP_NULL;
        } else {
                ipc_entry_t dest_entry, reply_entry;
-               ipc_port_t saved_reply;
 
                /*
                 *      This is the tough case to make atomic.
@@ -1326,6 +1391,8 @@ invalid_dest:
  *             MACH_MSG_INVALID_RT_DESCRIPTOR Dealloc and RT are incompatible
  */
 
+#define DESC_COUNT_SMALL 64
+
 mach_msg_return_t
 ipc_kmsg_copyin_body(
        ipc_kmsg_t      kmsg,
@@ -1334,73 +1401,111 @@ ipc_kmsg_copyin_body(
 {
     ipc_object_t                       dest;
     mach_msg_body_t            *body;
-    mach_msg_descriptor_t      *saddr, *eaddr;
-    boolean_t                  complex;
-    mach_msg_return_t          mr;
-    int                                i;
-    kern_return_t              kr;
+    mach_msg_descriptor_t      *daddr, *naddr;
+    mach_msg_type_number_t     dsc_count;
+    boolean_t                  differs = MAP_SIZE_DIFFERS(map);
+    boolean_t                  complex = FALSE;
     vm_size_t                  space_needed = 0;
+    vm_size_t                  desc_size_space[DESC_COUNT_SMALL];
+    vm_size_t                  *user_desc_sizes = NULL;
     vm_offset_t                        paddr = 0;
-    mach_msg_descriptor_t      *sstart;
     vm_map_copy_t              copy = VM_MAP_COPY_NULL;
+    kern_return_t              kr;
+    mach_msg_type_number_t     i;
+    mach_msg_return_t          mr = MACH_MSG_SUCCESS;
     
     /*
      * Determine if the target is a kernel port.
      */
-    dest = (ipc_object_t) kmsg->ikm_header.msgh_remote_port;
-    complex = FALSE;
+    dest = (ipc_object_t) kmsg->ikm_header->msgh_remote_port;
+    body = (mach_msg_body_t *) (kmsg->ikm_header + 1);
+    naddr = (mach_msg_descriptor_t *) (body + 1);
 
-    body = (mach_msg_body_t *) (&kmsg->ikm_header + 1);
-    saddr = (mach_msg_descriptor_t *) (body + 1);
-    eaddr = saddr + body->msgh_descriptor_count;
-    
-    /* make sure the message does not ask for more msg descriptors
-     * than the message can hold.
-     */
-    
-    if (eaddr <= saddr ||
-       eaddr > (mach_msg_descriptor_t *) (&kmsg->ikm_header + 
-                           kmsg->ikm_header.msgh_size)) {
-       ipc_kmsg_clean_partial(kmsg,0,0,0);
-       return MACH_SEND_MSG_TOO_SMALL;
+    dsc_count = body->msgh_descriptor_count;
+    if (dsc_count == 0)
+       return MACH_MSG_SUCCESS;
+
+    if (differs) {
+       user_desc_sizes = (dsc_count <= DESC_COUNT_SMALL) ?
+           &desc_size_space : kalloc(dsc_count * sizeof(vm_size_t));
+       if (user_desc_sizes == NULL) {
+           ipc_kmsg_clean_partial(kmsg,0,0,0,0);
+           return KERN_RESOURCE_SHORTAGE;
+       }
     }
-    
+
     /*
      * Make an initial pass to determine kernal VM space requirements for
-     * physical copies.
+     * physical copies and possible contraction of the descriptors from
+     * processes with pointers larger than the kernel's.
      */
-    for (sstart = saddr; sstart <  eaddr; sstart++) {
+    daddr = 0;
+    for (i = 0; i < dsc_count; i++) {
+       daddr = naddr;
+
+       /* make sure the descriptor fits in the message */
+       if (differs) {
+           switch (daddr->type.type) {
+           case MACH_MSG_OOL_DESCRIPTOR:
+           case MACH_MSG_OOL_VOLATILE_DESCRIPTOR:
+           case MACH_MSG_OOL_PORTS_DESCRIPTOR:
+               user_desc_sizes[i] = sizeof(OTHER_OOL_DESCRIPTOR);
+               break;
+           default:
+               user_desc_sizes[i] = sizeof(*daddr);
+               break;
+           }
+           naddr = (mach_msg_descriptor_t *)
+                   ((vm_offset_t)daddr + user_desc_sizes[i]);
+       } else {
+           naddr = daddr + 1;
+       }
 
-       if (sstart->type.type == MACH_MSG_OOL_DESCRIPTOR ||
-           sstart->type.type == MACH_MSG_OOL_VOLATILE_DESCRIPTOR) {
+       if (naddr > (mach_msg_descriptor_t *)
+           ((vm_offset_t)kmsg->ikm_header + kmsg->ikm_header->msgh_size)) {
+           ipc_kmsg_clean_partial(kmsg,0,0,0,0);
+           mr = MACH_SEND_MSG_TOO_SMALL;
+           goto out;
+       }
+
+       switch (daddr->type.type) {
+           mach_msg_size_t size;
+
+       case MACH_MSG_OOL_DESCRIPTOR:
+       case MACH_MSG_OOL_VOLATILE_DESCRIPTOR:
+           size = (differs) ?
+               ((OTHER_OOL_DESCRIPTOR *)daddr)->size :
+           daddr->out_of_line.size;
+
+           if (daddr->out_of_line.copy != MACH_MSG_PHYSICAL_COPY &&
+               daddr->out_of_line.copy != MACH_MSG_VIRTUAL_COPY) {
+               /*
+                * Invalid copy option
+                */
+               ipc_kmsg_clean_partial(kmsg,0,0,0,0);
+               mr = MACH_SEND_INVALID_TYPE;
+               goto out;
+           }
+           
+           if ((size >= MSG_OOL_SIZE_SMALL) &&
+               (daddr->out_of_line.copy == MACH_MSG_PHYSICAL_COPY) &&
+               !(daddr->out_of_line.deallocate)) {
 
-               if (sstart->out_of_line.copy != MACH_MSG_PHYSICAL_COPY &&
-                   sstart->out_of_line.copy != MACH_MSG_VIRTUAL_COPY) {
+               /*
+                * Out-of-line memory descriptor, accumulate kernel
+                * memory requirements
+                */
+               space_needed += round_page(size);
+               if (space_needed > ipc_kmsg_max_vm_space) {
+                   
                    /*
-                    * Invalid copy option
+                    * Per message kernel memory limit exceeded
                     */
-                   ipc_kmsg_clean_partial(kmsg,0,0,0);
-                   return MACH_SEND_INVALID_TYPE;
+                   ipc_kmsg_clean_partial(kmsg,0,0,0,0);
+                   mr = MACH_MSG_VM_KERNEL;
+                   goto out;
                }
-               
-               if ((sstart->out_of_line.size >= MSG_OOL_SIZE_SMALL) &&
-                   (sstart->out_of_line.copy == MACH_MSG_PHYSICAL_COPY) &&
-                   !(sstart->out_of_line.deallocate)) {
-
-                       /*
-                        * Out-of-line memory descriptor, accumulate kernel
-                        * memory requirements
-                        */
-                       space_needed += round_page(sstart->out_of_line.size);
-                       if (space_needed > ipc_kmsg_max_vm_space) {
-
-                               /*
-                                * Per message kernel memory limit exceeded
-                                */
-                               ipc_kmsg_clean_partial(kmsg,0,0,0);
-                               return MACH_MSG_VM_KERNEL;
-                       }
-               }
+           }
        }
     }
 
@@ -1410,69 +1515,106 @@ ipc_kmsg_copyin_body(
      * space.
      */
     if (space_needed) {
-       if (vm_allocate(ipc_kernel_copy_map, &paddr, space_needed, TRUE) !=
+       if (vm_allocate(ipc_kernel_copy_map, &paddr, space_needed, VM_FLAGS_ANYWHERE) !=
            KERN_SUCCESS) {
-               ipc_kmsg_clean_partial(kmsg,0,0,0);
-               return MACH_MSG_VM_KERNEL;
+           ipc_kmsg_clean_partial(kmsg,0,0,0,0);
+               mr = MACH_MSG_VM_KERNEL;
+               goto out;
        }
     }
 
     /* 
      * handle the OOL regions and port descriptors.
-     * the check for complex messages was done earlier.
+     * We process them in reverse order starting with the last one
+     * scanned above.  That way, we can compact them up against
+     * the message body (if the user-descriptor size is larger than
+     * the kernel representation).
      */
-    
-    for (i = 0, sstart = saddr; sstart <  eaddr; sstart++) {
-       
-       switch (sstart->type.type) {
+    naddr -= 1;
+    do {
+
+       switch (daddr->type.type) {
            
+           /* port descriptors are the same size everywhere, how nice */
            case MACH_MSG_PORT_DESCRIPTOR: {
-               mach_msg_type_name_t            name;
+               mach_msg_type_name_t            user_disp;
+               mach_msg_type_name_t            result_disp;
+               mach_port_name_t                name;
                ipc_object_t                    object;
-               mach_msg_port_descriptor_t      *dsc;
+               volatile mach_msg_port_descriptor_t     *dsc;
+               volatile mach_msg_port_descriptor_t     *user_dsc;
                
-               dsc = &sstart->port;
+               user_dsc = &daddr->port;
+               dsc = &naddr->port;
                
-               /* this is really the type SEND, SEND_ONCE, etc. */
-               name = dsc->disposition;
-               dsc->disposition = ipc_object_copyin_type(name);
+               user_disp = user_dsc->disposition;
+               result_disp = ipc_object_copyin_type(user_disp);
                
-               if (!MACH_PORT_VALID((mach_port_name_t)dsc->name)) {
-                   complex = TRUE;
-                   break;
-               }
-               kr = ipc_object_copyin(space, (mach_port_name_t)dsc->name, name, &object);
-               if (kr != KERN_SUCCESS) {
-                   ipc_kmsg_clean_partial(kmsg, i, paddr, space_needed);
-                   return MACH_SEND_INVALID_RIGHT;
-               }
-               if ((dsc->disposition == MACH_MSG_TYPE_PORT_RECEIVE) &&
-                   ipc_port_check_circularity((ipc_port_t) object,
-                                              (ipc_port_t) dest)) {
-                   kmsg->ikm_header.msgh_bits |= MACH_MSGH_BITS_CIRCULAR;
+               name = (mach_port_name_t)user_dsc->name;
+               if (MACH_PORT_VALID(name)) {
+
+                   kr = ipc_object_copyin(space, name, user_disp, &object);
+                   if (kr != KERN_SUCCESS) {
+                       mr = MACH_SEND_INVALID_RIGHT;
+                       break;
+                   }
+
+                   if ((result_disp == MACH_MSG_TYPE_PORT_RECEIVE) &&
+                       ipc_port_check_circularity((ipc_port_t) object,
+                                                  (ipc_port_t) dest)) {
+                       kmsg->ikm_header->msgh_bits |= MACH_MSGH_BITS_CIRCULAR;
+                   }
+                   dsc->name = (ipc_port_t) object;
+               } else {
+                   dsc->name = (mach_port_t)name;
                }
-               dsc->name = (ipc_port_t) object;
+               dsc->disposition = result_disp;
+               dsc->type = MACH_MSG_PORT_DESCRIPTOR;
                complex = TRUE;
                break;
            }
+
+           /* out of line descriptors differ in size between 32 and 64 bit processes */
            case MACH_MSG_OOL_VOLATILE_DESCRIPTOR:
            case MACH_MSG_OOL_DESCRIPTOR: {
                vm_size_t                       length;
                boolean_t                       dealloc;
-               vm_offset_t                     addr;
-               vm_offset_t                     kaddr;
-               mach_msg_ool_descriptor_t       *dsc;
-               
-               dsc = &sstart->out_of_line;
-               dealloc = dsc->deallocate;
-               addr = (vm_offset_t) dsc->address;
-               
-               length = dsc->size;
+               mach_msg_copy_options_t         copy_options;
+               mach_vm_offset_t                addr;
+               mach_msg_descriptor_type_t      dsc_type;
+
+               volatile mach_msg_ool_descriptor_t      *dsc;
+
+               if (differs) {
+                   volatile OTHER_OOL_DESCRIPTOR       *user_dsc;
+
+                   user_dsc = (OTHER_OOL_DESCRIPTOR *)&daddr->out_of_line;
+                   addr = (mach_vm_offset_t) user_dsc->address;
+                   length = user_dsc->size;
+                   dealloc = user_dsc->deallocate;
+                   copy_options = user_dsc->copy;
+                   dsc_type = user_dsc->type;
+               } else {
+                   volatile mach_msg_ool_descriptor_t  *user_dsc;
                
+                   user_dsc = &daddr->out_of_line;
+                   addr = CAST_USER_ADDR_T(user_dsc->address);
+                   dealloc = user_dsc->deallocate;
+                   copy_options = user_dsc->copy;
+                   dsc_type = user_dsc->type;
+                   length = user_dsc->size;
+               }
+
+               dsc = &naddr->out_of_line;
+               dsc->size = length;
+               dsc->deallocate = dealloc;
+               dsc->copy = copy_options;
+               dsc->type = dsc_type;
+
                if (length == 0) {
                    dsc->address = 0;
                } else if ((length >= MSG_OOL_SIZE_SMALL) &&
-                          (dsc->copy == MACH_MSG_PHYSICAL_COPY) && !dealloc) {
+                          (copy_options == MACH_MSG_PHYSICAL_COPY) && !dealloc) {
 
                        /*
                         * If the request is a physical copy and the source
@@ -1484,11 +1626,9 @@ ipc_kmsg_copyin_body(
                         * is not being deallocated, we must be prepared
                         * to page if the region is sufficiently large.
                         */
-                       if (copyin((const char *) addr, (char *) paddr, 
-                                                               length)) {
-                               ipc_kmsg_clean_partial(kmsg, i, paddr, 
-                                                          space_needed);
-                               return MACH_SEND_INVALID_MEMORY;
+                       if (copyin(addr, (char *) paddr, length)) {
+                               mr = MACH_SEND_INVALID_MEMORY;
+                               break;
                        }       
 
                        /*
@@ -1500,11 +1640,10 @@ ipc_kmsg_copyin_body(
                                (void) memset((void *) (paddr + length), 0,
                                        round_page(length) - length);
                        }
-                       if (vm_map_copyin(ipc_kernel_copy_map, paddr, length,
-                                          TRUE, &copy) != KERN_SUCCESS) {
-                           ipc_kmsg_clean_partial(kmsg, i, paddr, 
-                                                      space_needed);
-                           return MACH_MSG_VM_KERNEL;
+                       if (vm_map_copyin(ipc_kernel_copy_map, (vm_map_address_t)paddr,
+                                         (vm_map_size_t)length, TRUE, &copy) != KERN_SUCCESS) {
+                           mr = MACH_MSG_VM_KERNEL;
+                           break;
                        }
                        dsc->address = (void *) copy;
                        paddr += round_page(length);
@@ -1519,12 +1658,13 @@ ipc_kmsg_copyin_body(
                         * NOTE: A virtual copy is OK if the original is being
                         * deallocted, even if a physical copy was requested.
                         */
-                       kr = vm_map_copyin(map, addr, length, dealloc, &copy);
+                       kr = vm_map_copyin(map, addr, 
+                                          (vm_map_size_t)length, dealloc, &copy);
                        if (kr != KERN_SUCCESS) {
-                           ipc_kmsg_clean_partial(kmsg,i,paddr,space_needed);
-                           return (kr == KERN_RESOURCE_SHORTAGE) ?
+                           mr = (kr == KERN_RESOURCE_SHORTAGE) ?
                                   MACH_MSG_VM_KERNEL :
                                   MACH_SEND_INVALID_MEMORY;
+                           break;
                        }
                        dsc->address = (void *) copy;
                }
@@ -1533,18 +1673,46 @@ ipc_kmsg_copyin_body(
            }
            case MACH_MSG_OOL_PORTS_DESCRIPTOR: {
                vm_size_t                               length;
-               vm_offset_t                             data;
-               vm_offset_t                             addr;
+               void                                    *data;
                ipc_object_t                            *objects;
-               int                                     j;
-               mach_msg_type_name_t                    name;
-               mach_msg_ool_ports_descriptor_t         *dsc;
-               
-               dsc = &sstart->ool_ports;
-               addr = (vm_offset_t) dsc->address;
+               unsigned int                            j;
+               mach_vm_offset_t                        addr;
+               mach_msg_type_name_t                    user_disp;
+               mach_msg_type_name_t                    result_disp;
+               mach_msg_type_number_t                  count;
+               mach_msg_copy_options_t                 copy_option;
+               boolean_t                               deallocate;
+
+               volatile mach_msg_ool_ports_descriptor_t        *dsc;
+
+               if (differs) {
+                   volatile OTHER_OOL_PORTS_DESCRIPTOR         *user_dsc;
+                   
+                   user_dsc = (OTHER_OOL_PORTS_DESCRIPTOR *)&daddr->ool_ports;
+                   addr = (mach_vm_offset_t)user_dsc->address;
+                   count = user_dsc->count;
+                   deallocate = user_dsc->deallocate;
+                   copy_option = user_dsc->copy;
+                   user_disp = user_dsc->disposition;
+               } else {
+                   volatile mach_msg_ool_ports_descriptor_t    *user_dsc;
+
+                   user_dsc = &daddr->ool_ports;
+                   addr = CAST_USER_ADDR_T(user_dsc->address);
+                   count = user_dsc->count;
+                   deallocate = user_dsc->deallocate;
+                   copy_option = user_dsc->copy;
+                   user_disp = user_dsc->disposition;
+               }
+
+               dsc = &naddr->ool_ports;
+               dsc->deallocate = deallocate;
+               dsc->copy = copy_option;
+               dsc->type = daddr->type.type;
+               dsc->count = count;
 
                /* calculate length of data in bytes, rounding up */
-               length = dsc->count * sizeof(mach_port_name_t);
+               length = count * sizeof(mach_port_name_t);
                
                if (length == 0) {
                    complex = TRUE;
@@ -1554,57 +1722,55 @@ ipc_kmsg_copyin_body(
 
                data = kalloc(length);
 
-               if (data == 0) {
-                   ipc_kmsg_clean_partial(kmsg, i, paddr, space_needed);
-                   return MACH_SEND_NO_BUFFER;
+               if (data == NULL) {
+                   mr = MACH_SEND_NO_BUFFER;
+                   break;
                }
                
-               if (copyinmap(map, addr, data, length)) {
+               if (copyinmap(map, addr, data, length) != KERN_SUCCESS) {
                    kfree(data, length);
-                   ipc_kmsg_clean_partial(kmsg, i, paddr, space_needed);
-                   return MACH_SEND_INVALID_MEMORY;
+                   mr = MACH_SEND_INVALID_MEMORY;
+                   break;
                }
 
-               if (dsc->deallocate) {
-                       (void) vm_deallocate(map, addr, length);
+               if (deallocate) {
+                   (void) mach_vm_deallocate(map, addr, (mach_vm_size_t)length);
                }
                
-               dsc->address = (void *) data;
-               
-               /* this is really the type SEND, SEND_ONCE, etc. */
-               name = dsc->disposition;
-               dsc->disposition = ipc_object_copyin_type(name);
+               dsc->address = data;
                
+               result_disp = ipc_object_copyin_type(user_disp);
+               dsc->disposition = result_disp;
+
                objects = (ipc_object_t *) data;
                
-               for ( j = 0; j < dsc->count; j++) {
+               for ( j = 0; j < count; j++) {
                    mach_port_name_t port = (mach_port_name_t) objects[j];
                    ipc_object_t object;
                    
                    if (!MACH_PORT_VALID(port))
                        continue;
                    
-                   kr = ipc_object_copyin(space, port, name, &object);
+                   kr = ipc_object_copyin(space, port, user_disp, &object);
 
                    if (kr != KERN_SUCCESS) {
-                       int k;
+                       unsigned int k;
 
                        for(k = 0; k < j; k++) {
                            object = objects[k];
-                           if (!MACH_PORT_VALID(port))
-                               continue;
-                           ipc_object_destroy(object, dsc->disposition);
+                           if (IPC_OBJECT_VALID(object))
+                               ipc_object_destroy(object, result_disp);
                        }
                        kfree(data, length);
-                       ipc_kmsg_clean_partial(kmsg, i, paddr, space_needed);
-                       return MACH_SEND_INVALID_RIGHT;
+                       mr = MACH_SEND_INVALID_RIGHT;
+                       break;
                    }
                    
                    if ((dsc->disposition == MACH_MSG_TYPE_PORT_RECEIVE) &&
                        ipc_port_check_circularity(
                                                   (ipc_port_t) object,
                                                   (ipc_port_t) dest))
-                       kmsg->ikm_header.msgh_bits |= MACH_MSGH_BITS_CIRCULAR;
+                       kmsg->ikm_header->msgh_bits |= MACH_MSGH_BITS_CIRCULAR;
                    
                    objects[j] = object;
                }
@@ -1616,16 +1782,42 @@ ipc_kmsg_copyin_body(
                /*
                 * Invalid descriptor
                 */
-               ipc_kmsg_clean_partial(kmsg, i, paddr, space_needed);
-               return MACH_SEND_INVALID_TYPE;
+               mr = MACH_SEND_INVALID_TYPE;
+               break;
            }
        }
-       i++ ;
-    }
+
+       if (MACH_MSG_SUCCESS != mr) {
+           ipc_kmsg_clean_partial(kmsg, dsc_count - i,
+                                  naddr + 1, paddr, space_needed);
+           goto out;
+       }
+
+    } while (--i > 0
+            && 
+            (daddr = (differs) ? (mach_msg_descriptor_t *)((vm_offset_t)(daddr) -
+                                 user_desc_sizes[i - 1]) : daddr - 1)
+            &&
+            naddr--);
     
-    if (!complex)
-       kmsg->ikm_header.msgh_bits &= ~MACH_MSGH_BITS_COMPLEX;
-    return MACH_MSG_SUCCESS;
+    if (!complex) {
+       kmsg->ikm_header->msgh_bits &= ~MACH_MSGH_BITS_COMPLEX;
+    }
+
+    if (differs && naddr != daddr) {
+       mach_msg_base_t *old_base = (mach_msg_base_t *)kmsg->ikm_header;
+       mach_msg_base_t *new_base = (mach_msg_base_t *)naddr - 1;
+
+       memmove(new_base, old_base, sizeof(mach_msg_base_t));
+       new_base->header.msgh_size -= (vm_offset_t)naddr - (vm_offset_t)daddr;
+       kmsg->ikm_header = &new_base->header;
+    }
+
+ out:
+    if (differs && dsc_count > DESC_COUNT_SMALL)
+       kfree(user_desc_sizes, body->msgh_descriptor_count * sizeof(vm_size_t));
+
+    return mr;
 }
 
 
@@ -1663,11 +1855,11 @@ ipc_kmsg_copyin(
 {
     mach_msg_return_t          mr;
     
-    mr = ipc_kmsg_copyin_header(&kmsg->ikm_header, space, notify);
+    mr = ipc_kmsg_copyin_header(kmsg->ikm_header, space, notify);
     if (mr != MACH_MSG_SUCCESS)
        return mr;
     
-    if ((kmsg->ikm_header.msgh_bits & MACH_MSGH_BITS_COMPLEX) == 0)
+    if ((kmsg->ikm_header->msgh_bits & MACH_MSGH_BITS_COMPLEX) == 0)
        return MACH_MSG_SUCCESS;
     
     return( ipc_kmsg_copyin_body( kmsg, space, map) );
@@ -1693,11 +1885,11 @@ void
 ipc_kmsg_copyin_from_kernel(
        ipc_kmsg_t      kmsg)
 {
-       mach_msg_bits_t bits = kmsg->ikm_header.msgh_bits;
+       mach_msg_bits_t bits = kmsg->ikm_header->msgh_bits;
        mach_msg_type_name_t rname = MACH_MSGH_BITS_REMOTE(bits);
        mach_msg_type_name_t lname = MACH_MSGH_BITS_LOCAL(bits);
-       ipc_object_t remote = (ipc_object_t) kmsg->ikm_header.msgh_remote_port;
-       ipc_object_t local = (ipc_object_t) kmsg->ikm_header.msgh_local_port;
+       ipc_object_t remote = (ipc_object_t) kmsg->ikm_header->msgh_remote_port;
+       ipc_object_t local = (ipc_object_t) kmsg->ikm_header->msgh_local_port;
 
        /* translate the destination and reply ports */
 
@@ -1715,13 +1907,13 @@ ipc_kmsg_copyin_from_kernel(
                bits = (MACH_MSGH_BITS_COMPLEX |
                        MACH_MSGH_BITS(MACH_MSG_TYPE_PORT_SEND, 0));
 
-               kmsg->ikm_header.msgh_bits = bits;
+               kmsg->ikm_header->msgh_bits = bits;
        } else {
                bits = (MACH_MSGH_BITS_OTHER(bits) |
                        MACH_MSGH_BITS(ipc_object_copyin_type(rname),
                                       ipc_object_copyin_type(lname)));
 
-               kmsg->ikm_header.msgh_bits = bits;
+               kmsg->ikm_header->msgh_bits = bits;
                if ((bits & MACH_MSGH_BITS_COMPLEX) == 0)
                        return;
        }
@@ -1729,7 +1921,7 @@ ipc_kmsg_copyin_from_kernel(
        mach_msg_descriptor_t   *saddr, *eaddr;
        mach_msg_body_t         *body;
 
-       body = (mach_msg_body_t *) (&kmsg->ikm_header + 1);
+       body = (mach_msg_body_t *) (kmsg->ikm_header + 1);
        saddr = (mach_msg_descriptor_t *) (body + 1);
        eaddr = (mach_msg_descriptor_t *) saddr + body->msgh_descriptor_count;
 
@@ -1764,7 +1956,7 @@ ipc_kmsg_copyin_from_kernel(
                       if ((dsc->disposition == MACH_MSG_TYPE_PORT_RECEIVE) &&
                           ipc_port_check_circularity((ipc_port_t) object, 
                                                (ipc_port_t) remote)) {
-                          kmsg->ikm_header.msgh_bits |= 
+                          kmsg->ikm_header->msgh_bits |= 
                                        MACH_MSGH_BITS_CIRCULAR;
                       }
                    }
@@ -1780,7 +1972,7 @@ ipc_kmsg_copyin_from_kernel(
                }
                case MACH_MSG_OOL_PORTS_DESCRIPTOR: {
                    ipc_object_t                        *objects;
-                   int                                 j;
+                   unsigned int                        j;
                    mach_msg_type_name_t                name;
                    mach_msg_ool_ports_descriptor_t     *dsc;
                
@@ -1804,7 +1996,7 @@ ipc_kmsg_copyin_from_kernel(
                            ipc_port_check_circularity(
                                                       (ipc_port_t) object,
                                                       (ipc_port_t) remote))
-                           kmsg->ikm_header.msgh_bits |= MACH_MSGH_BITS_CIRCULAR;
+                           kmsg->ikm_header->msgh_bits |= MACH_MSGH_BITS_CIRCULAR;
                    }
                    break;
                }
@@ -2231,178 +2423,326 @@ ipc_kmsg_copyout_body(
        mach_msg_body_t         *slist)
 {
     mach_msg_body_t            *body;
-    mach_msg_descriptor_t      *saddr, *eaddr;
+    mach_msg_descriptor_t      *daddr, *naddr;
+    mach_msg_descriptor_t      *saddr;
+    mach_msg_type_number_t     i, dsc_count, sdsc_count;
     mach_msg_return_t          mr = MACH_MSG_SUCCESS;
     kern_return_t              kr;
-    vm_offset_t                data;
-    mach_msg_descriptor_t      *sstart, *send;
+    void                       *data;
+    boolean_t                  differs = MAP_SIZE_DIFFERS(map);
 
-    body = (mach_msg_body_t *) (&kmsg->ikm_header + 1);
-    saddr = (mach_msg_descriptor_t *) (body + 1);
-    eaddr = saddr + body->msgh_descriptor_count;
+    body = (mach_msg_body_t *) (kmsg->ikm_header + 1);
+    dsc_count = body->msgh_descriptor_count;
+    daddr = (mach_msg_descriptor_t *) (body + 1);
 
     /*
      * Do scatter list setup
      */
     if (slist != MACH_MSG_BODY_NULL) {
-       sstart = (mach_msg_descriptor_t *) (slist + 1);
-       send = sstart + slist->msgh_descriptor_count;
+       saddr = (mach_msg_descriptor_t *) (slist + 1);
+       sdsc_count = slist->msgh_descriptor_count;
     }
     else {
-       sstart = MACH_MSG_DESCRIPTOR_NULL;
+       saddr = MACH_MSG_DESCRIPTOR_NULL;
+       sdsc_count = 0;
     }
 
-    for ( ; saddr < eaddr; saddr++ ) {
-       
-       switch (saddr->type.type) {
+    /*
+     * Compute the true size of the resulting descriptors
+     * after potential expansion and adjust the header
+     * and body location accordingly.
+     */
+    if (differs) {
+       mach_msg_size_t dsc_adjust;
+
+       naddr = daddr;
+       dsc_adjust = 0;
+       for (i = 0; i < dsc_count; i++, naddr++)
+           switch (naddr->type.type) {
+           case MACH_MSG_OOL_DESCRIPTOR:
+           case MACH_MSG_OOL_VOLATILE_DESCRIPTOR:
+           case MACH_MSG_OOL_PORTS_DESCRIPTOR:
+               dsc_adjust += DESC_SIZE_ADJUSTMENT;
+               break;
+           default:
+               break;
+           }
+       if (dsc_adjust) {
+           mach_msg_base_t *old_base = (mach_msg_base_t *)kmsg->ikm_header;
+           mach_msg_base_t *new_base;
+
+           new_base = (mach_msg_base_t *)((vm_offset_t)old_base - dsc_adjust);
+           memmove(new_base, old_base, sizeof(mach_msg_base_t));
+           kmsg->ikm_header = &new_base->header;
+           kmsg->ikm_header->msgh_size += dsc_adjust;
+           naddr = (mach_msg_descriptor_t *)(new_base + 1);
+       } else {
+           naddr = daddr;
+       }
+    } else {
+       naddr = daddr;
+    }
+
+    /*
+     * Now process the descriptors
+     */
+    for ( i = 0; i < dsc_count; i++, daddr++ ) {
+       switch (daddr->type.type) {
            
            case MACH_MSG_PORT_DESCRIPTOR: {
-               mach_msg_port_descriptor_t *dsc;
+               volatile mach_msg_port_descriptor_t *dsc;
+               volatile mach_msg_port_descriptor_t *user_dsc;
+               mach_port_t                     port;
+               mach_port_name_t                name;
+               mach_msg_type_name_t            disp;
                
                /* 
                 * Copyout port right carried in the message 
                 */
-               dsc = &saddr->port;
+               dsc = &daddr->port;
+               user_dsc = &naddr->port;
+               port = dsc->name;
+               disp = dsc->disposition;
                mr |= ipc_kmsg_copyout_object(space, 
-                                             (ipc_object_t) dsc->name, 
-                                             dsc->disposition, 
-                                             (mach_port_name_t *) &dsc->name);
-
+                                             (ipc_object_t)port, 
+                                             disp, 
+                                             &name);
+               user_dsc->name = (mach_port_t)name;
+               user_dsc->disposition = disp;
+               user_dsc->type = MACH_MSG_PORT_DESCRIPTOR;
+               naddr++;
                break;
            }
+
            case MACH_MSG_OOL_VOLATILE_DESCRIPTOR:
            case MACH_MSG_OOL_DESCRIPTOR : {
-               vm_offset_t                     rcv_addr;
-               vm_offset_t                     snd_addr;
+               vm_map_copy_t                   copy;
+               mach_vm_offset_t                rcv_addr;
                mach_msg_ool_descriptor_t       *dsc;
-               mach_msg_copy_options_t         copy_option;
+               mach_msg_copy_options_t         copy_options;
+               mach_msg_size_t                 size;
+               mach_msg_descriptor_type_t      dsc_type;
 
-               SKIP_PORT_DESCRIPTORS(sstart, send);
+               SKIP_PORT_DESCRIPTORS(saddr, sdsc_count);
 
-               dsc = &saddr->out_of_line;
-
-               assert(dsc->copy != MACH_MSG_KALLOC_COPY_T);
+               dsc = &daddr->out_of_line;
+               copy = (vm_map_copy_t) dsc->address;
+               size = dsc->size;
+               copy_options = dsc->copy;
+               assert(copy_options != MACH_MSG_KALLOC_COPY_T);
+               dsc_type = dsc->type;
 
-               copy_option = dsc->copy;
-
-               if ((snd_addr = (vm_offset_t) dsc->address) != 0) {
-                   if (sstart != MACH_MSG_DESCRIPTOR_NULL &&
-                       sstart->out_of_line.copy == MACH_MSG_OVERWRITE) {
+               if (copy != VM_MAP_COPY_NULL) {
+                   /*
+                    * Check to see if there is an overwrite descriptor
+                    * specified in the scatter list for this ool data.
+                    * The descriptor has already been verified.
+                    */
+                   if (saddr != MACH_MSG_DESCRIPTOR_NULL) {
+                       if (differs) {
+                           OTHER_OOL_DESCRIPTOR *scatter_dsc;
+
+                           scatter_dsc = (OTHER_OOL_DESCRIPTOR *)saddr;
+                           if (scatter_dsc->copy == MACH_MSG_OVERWRITE) {
+                               rcv_addr = (mach_vm_offset_t) scatter_dsc->address;
+                               copy_options = MACH_MSG_OVERWRITE;
+                           } else {
+                               rcv_addr = 0;
+                               copy_options = MACH_MSG_VIRTUAL_COPY;
+                           }
+                       } else {
+                           mach_msg_ool_descriptor_t *scatter_dsc;
 
-                       /*
-                        * There is an overwrite descriptor specified in the
-                        * scatter list for this ool data.  The descriptor
-                        * has already been verified
-                        */
-                       rcv_addr = (vm_offset_t) sstart->out_of_line.address;
-                       dsc->copy = MACH_MSG_OVERWRITE;
-                   } else {
-                       dsc->copy = MACH_MSG_ALLOCATE;
+                           scatter_dsc = &saddr->out_of_line;
+                           if (scatter_dsc->copy == MACH_MSG_OVERWRITE) {
+                               rcv_addr = CAST_USER_ADDR_T(scatter_dsc->address);
+                               copy_options = MACH_MSG_OVERWRITE;
+                           } else {
+                               rcv_addr = 0;
+                               copy_options = MACH_MSG_VIRTUAL_COPY;
+                           }
+                       }
+                       INCREMENT_SCATTER(saddr, sdsc_count, differs);
                    }
 
+
                    /*
                     * Whether the data was virtually or physically
                     * copied we have a vm_map_copy_t for it.
                     * If there's an overwrite region specified
                     * overwrite it, otherwise do a virtual copy out.
                     */
-                   if (dsc->copy == MACH_MSG_OVERWRITE) {
+                   if (copy_options == MACH_MSG_OVERWRITE) {
                            kr = vm_map_copy_overwrite(map, rcv_addr,
-                                           (vm_map_copy_t) dsc->address, TRUE);
+                                           copy, TRUE);
                    } else {
-                           kr = vm_map_copyout(map, &rcv_addr, 
-                                               (vm_map_copy_t) dsc->address);
+                           kr = vm_map_copyout(map, &rcv_addr, copy);
                    }   
                    if (kr != KERN_SUCCESS) {
                            if (kr == KERN_RESOURCE_SHORTAGE)
                                    mr |= MACH_MSG_VM_KERNEL;
                            else
                                    mr |= MACH_MSG_VM_SPACE;
-                           vm_map_copy_discard((vm_map_copy_t) dsc->address);
-                           dsc->address = 0;
-                           INCREMENT_SCATTER(sstart);
-                           break;
+                           vm_map_copy_discard(copy);
+                           rcv_addr = 0;
+                           size = 0;
                    }
-                   dsc->address = (void *) rcv_addr;
+               } else {
+                   rcv_addr = 0;
+                   size = 0;
+               }
+
+               /*
+                * Now update the descriptor as the user would see it.
+                * This may require expanding the descriptor to the user
+                * visible size.  There is already space allocated for
+                * this in what naddr points to.
+                */
+               if (differs) {
+                   volatile OTHER_OOL_DESCRIPTOR *user_dsc;
+                   
+                   user_dsc = (OTHER_OOL_DESCRIPTOR *)naddr;
+                   user_dsc->address = rcv_addr;
+                   user_dsc->deallocate = (copy_options == MACH_MSG_VIRTUAL_COPY) ?
+                                          TRUE : FALSE;
+                   user_dsc->copy = copy_options;
+                   user_dsc->type = dsc_type;
+                   user_dsc->size = size;
+                   naddr = (mach_msg_descriptor_t *)((OTHER_OOL_DESCRIPTOR *)naddr + 1);
+               } else {
+                   volatile mach_msg_ool_descriptor_t *user_dsc;
+                   
+                   user_dsc = &naddr->out_of_line;
+                   user_dsc->address = CAST_DOWN(void *, rcv_addr);
+                   user_dsc->size = size;
+                   user_dsc->deallocate = (copy_options == MACH_MSG_VIRTUAL_COPY) ?
+                                          TRUE : FALSE;
+                   user_dsc->copy = copy_options;
+                   user_dsc->type = dsc_type;
+                   naddr++;
                }
-               INCREMENT_SCATTER(sstart);
                break;
            }
+
            case MACH_MSG_OOL_PORTS_DESCRIPTOR : {
-               vm_offset_t                     addr;
+               mach_vm_offset_t                rcv_addr;
                mach_port_name_t                *objects;
-               mach_msg_type_number_t          j;
+               mach_msg_type_name_t            disp;
+               mach_msg_type_number_t          count, j;
                vm_size_t                       length;
-               mach_msg_ool_ports_descriptor_t *dsc;
 
-               SKIP_PORT_DESCRIPTORS(sstart, send);
+               volatile mach_msg_ool_ports_descriptor_t        *dsc;
+               mach_msg_copy_options_t copy_options = MACH_MSG_VIRTUAL_COPY;
 
-               dsc = &saddr->ool_ports;
+               SKIP_PORT_DESCRIPTORS(saddr, sdsc_count);
 
-               length = dsc->count * sizeof(mach_port_name_t);
+               dsc = &daddr->ool_ports;
+               count = dsc->count;
+               disp = dsc->disposition;
+               length = count * sizeof(mach_port_name_t);
 
-               if (length != 0) {
-                   if (sstart != MACH_MSG_DESCRIPTOR_NULL &&
-                       sstart->ool_ports.copy == MACH_MSG_OVERWRITE) {
+               if (length != 0 && dsc->address != 0) {
 
-                       /*
-                        * There is an overwrite descriptor specified in the
-                        * scatter list for this ool data.  The descriptor
-                        * has already been verified
-                        */
-                       addr = (vm_offset_t) sstart->out_of_line.address;
-                       dsc->copy = MACH_MSG_OVERWRITE;
-                   } 
-                   else {
+                   /*
+                    * Check to see if there is an overwrite descriptor
+                    * specified in the scatter list for this ool data.
+                    * The descriptor has already been verified.
+                    */
+                   if (saddr != MACH_MSG_DESCRIPTOR_NULL) {
+                       if (differs) {
+                           OTHER_OOL_DESCRIPTOR *scatter_dsc;
+
+                           scatter_dsc = (OTHER_OOL_DESCRIPTOR *)saddr;
+                           rcv_addr = (mach_vm_offset_t) scatter_dsc->address;
+                           copy_options = scatter_dsc->copy;
+                       } else {
+                           mach_msg_ool_descriptor_t *scatter_dsc;
 
+                           scatter_dsc = &saddr->out_of_line;
+                           rcv_addr = CAST_USER_ADDR_T(scatter_dsc->address);
+                           copy_options = scatter_dsc->copy;
+                       }
+                       INCREMENT_SCATTER(saddr, sdsc_count, differs);
+                   }
+
+                   if (copy_options == MACH_MSG_VIRTUAL_COPY) {
                        /*
                         * Dynamically allocate the region
                         */
                        int anywhere = VM_MAKE_TAG(VM_MEMORY_MACH_MSG)|
                                       VM_FLAGS_ANYWHERE;
 
-                       dsc->copy = MACH_MSG_ALLOCATE;
-                       if ((kr = vm_allocate(map, &addr, length,
+                       if ((kr = mach_vm_allocate(map, &rcv_addr, 
+                                             (mach_vm_size_t)length,
                                              anywhere)) != KERN_SUCCESS) {
-                           ipc_kmsg_clean_body(kmsg,
-                                               body->msgh_descriptor_count);
-                           dsc->address = 0;
+                           ipc_kmsg_clean_body(kmsg, 1, daddr);
+                           rcv_addr = 0;
 
                            if (kr == KERN_RESOURCE_SHORTAGE){
                                mr |= MACH_MSG_VM_KERNEL;
                            } else {
                                mr |= MACH_MSG_VM_SPACE;
                            }
-                           INCREMENT_SCATTER(sstart);
-                           break;
-                       }
+                       }
                    }
-               } else {
-                   INCREMENT_SCATTER(sstart);
-                   break;
-               }
 
+
+                   /*
+                    * Handle the port rights and copy out the names
+                    * for those rights out to user-space.
+                    */
+                   if (rcv_addr != 0) {
+                       objects = (mach_port_name_t *) dsc->address ;
                
-               objects = (mach_port_name_t *) dsc->address ;
-               
-               /* copyout port rights carried in the message */
+                       /* copyout port rights carried in the message */
                
-               for ( j = 0; j < dsc->count ; j++) {
-                   ipc_object_t object =
-                       (ipc_object_t) objects[j];
+                       for ( j = 0; j < count ; j++) {
+                           ipc_object_t object =
+                               (ipc_object_t) objects[j];
                    
-                   mr |= ipc_kmsg_copyout_object(space, object,
-                                       dsc->disposition, &objects[j]);
+                           mr |= ipc_kmsg_copyout_object(space, object,
+                                                         disp, &objects[j]);
+                       }
+
+                       /* copyout to memory allocated above */
+                       data = dsc->address;
+                       if (copyoutmap(map, data, rcv_addr, length) != KERN_SUCCESS)
+                           mr |= MACH_MSG_VM_SPACE;
+                       kfree(data, length);
+                   }
+               } else {
+                   rcv_addr = 0;
                }
 
-               /* copyout to memory allocated above */
-               
-               data = (vm_offset_t) dsc->address;
-               (void) copyoutmap(map, data, addr, length);
-               kfree(data, length);
-               
-               dsc->address = (void *) addr;
-               INCREMENT_SCATTER(sstart);
+               /*
+                * Now update the descriptor based on the information
+                * calculated above.
+                */
+               if (differs) {
+                   volatile OTHER_OOL_PORTS_DESCRIPTOR *user_dsc;
+                   
+                   user_dsc = (OTHER_OOL_PORTS_DESCRIPTOR *)naddr;
+                   user_dsc->address = rcv_addr;
+                   user_dsc->deallocate = (copy_options == MACH_MSG_VIRTUAL_COPY) ?
+                                          TRUE : FALSE;
+                   user_dsc->copy = copy_options;
+                   user_dsc->disposition = disp;
+                   user_dsc->type = MACH_MSG_OOL_PORTS_DESCRIPTOR;
+                   user_dsc->count = count;
+                   naddr = (mach_msg_descriptor_t *)((OTHER_OOL_PORTS_DESCRIPTOR *)naddr + 1);
+               } else {
+                   volatile mach_msg_ool_ports_descriptor_t *user_dsc;
+                   
+                   user_dsc = &naddr->ool_ports;
+                   user_dsc->address = CAST_DOWN(void *, rcv_addr);
+                   user_dsc->count = count;
+                   user_dsc->deallocate = (copy_options == MACH_MSG_VIRTUAL_COPY) ?
+                                          TRUE : FALSE;
+                   user_dsc->copy = copy_options;
+                   user_dsc->disposition = disp;
+                   user_dsc->type = MACH_MSG_OOL_PORTS_DESCRIPTOR;
+                   naddr++;
+               }
                break;
            }
            default : {
@@ -2413,6 +2753,55 @@ ipc_kmsg_copyout_body(
     return mr;
 }
 
+/*
+ *     Routine:        ipc_kmsg_copyout_size
+ *     Purpose:
+ *             Compute the size of the message as copied out to the given
+ *             map. If the destination map's pointers are a different size
+ *             than the kernel's, we have to allow for expansion/
+ *             contraction of the descriptors as appropriate.
+ *     Conditions:
+ *             Nothing locked.
+ *     Returns:
+ *             size of the message as it would be received.
+ */
+
+mach_msg_size_t
+ipc_kmsg_copyout_size(
+       ipc_kmsg_t              kmsg,
+       vm_map_t                map)
+{
+       mach_msg_size_t         send_size;
+
+       send_size = kmsg->ikm_header->msgh_size;
+
+       if ((kmsg->ikm_header->msgh_bits & MACH_MSGH_BITS_COMPLEX) &&
+           MAP_SIZE_DIFFERS(map)) {
+
+               mach_msg_body_t *body;
+               mach_msg_descriptor_t *saddr, *eaddr;
+
+               body = (mach_msg_body_t *) (kmsg->ikm_header + 1);
+               saddr = (mach_msg_descriptor_t *) (body + 1);
+               eaddr = saddr + body->msgh_descriptor_count;
+               
+               for ( ; saddr < eaddr; saddr++ ) {
+                       switch (saddr->type.type) {
+
+                       case MACH_MSG_OOL_DESCRIPTOR:
+                       case MACH_MSG_OOL_VOLATILE_DESCRIPTOR:
+                       case MACH_MSG_OOL_PORTS_DESCRIPTOR:
+                               send_size += DESC_SIZE_ADJUSTMENT;
+                               break;
+
+                       default:
+                               break;
+                       }
+               }
+       }
+       return send_size;
+}
+
 /*
  *     Routine:        ipc_kmsg_copyout
  *     Purpose:
@@ -2441,11 +2830,11 @@ ipc_kmsg_copyout(
 {
        mach_msg_return_t mr;
 
-       mr = ipc_kmsg_copyout_header(&kmsg->ikm_header, space, notify);
+       mr = ipc_kmsg_copyout_header(kmsg->ikm_header, space, notify);
        if (mr != MACH_MSG_SUCCESS)
                return mr;
 
-       if (kmsg->ikm_header.msgh_bits & MACH_MSGH_BITS_COMPLEX) {
+       if (kmsg->ikm_header->msgh_bits & MACH_MSGH_BITS_COMPLEX) {
                mr = ipc_kmsg_copyout_body(kmsg, space, map, slist);
 
                if (mr != MACH_MSG_SUCCESS)
@@ -2482,9 +2871,9 @@ ipc_kmsg_copyout_pseudo(
        vm_map_t                map,
        mach_msg_body_t         *slist)
 {
-       mach_msg_bits_t mbits = kmsg->ikm_header.msgh_bits;
-       ipc_object_t dest = (ipc_object_t) kmsg->ikm_header.msgh_remote_port;
-       ipc_object_t reply = (ipc_object_t) kmsg->ikm_header.msgh_local_port;
+       mach_msg_bits_t mbits = kmsg->ikm_header->msgh_bits;
+       ipc_object_t dest = (ipc_object_t) kmsg->ikm_header->msgh_remote_port;
+       ipc_object_t reply = (ipc_object_t) kmsg->ikm_header->msgh_local_port;
        mach_msg_type_name_t dest_type = MACH_MSGH_BITS_REMOTE(mbits);
        mach_msg_type_name_t reply_type = MACH_MSGH_BITS_LOCAL(mbits);
        mach_port_name_t dest_name, reply_name;
@@ -2495,9 +2884,9 @@ ipc_kmsg_copyout_pseudo(
        mr = (ipc_kmsg_copyout_object(space, dest, dest_type, &dest_name) |
              ipc_kmsg_copyout_object(space, reply, reply_type, &reply_name));
 
-       kmsg->ikm_header.msgh_bits = mbits &~ MACH_MSGH_BITS_CIRCULAR;
-       kmsg->ikm_header.msgh_remote_port = (ipc_port_t)dest_name;
-       kmsg->ikm_header.msgh_local_port = (ipc_port_t)reply_name;
+       kmsg->ikm_header->msgh_bits = mbits &~ MACH_MSGH_BITS_CIRCULAR;
+       kmsg->ikm_header->msgh_remote_port = (ipc_port_t)dest_name;
+       kmsg->ikm_header->msgh_local_port = (ipc_port_t)reply_name;
 
        if (mbits & MACH_MSGH_BITS_COMPLEX) {
                mr |= ipc_kmsg_copyout_body(kmsg, space, map, slist);
@@ -2527,9 +2916,9 @@ ipc_kmsg_copyout_dest(
        mach_msg_type_name_t reply_type;
        mach_port_name_t dest_name, reply_name;
 
-       mbits = kmsg->ikm_header.msgh_bits;
-       dest = (ipc_object_t) kmsg->ikm_header.msgh_remote_port;
-       reply = (ipc_object_t) kmsg->ikm_header.msgh_local_port;
+       mbits = kmsg->ikm_header->msgh_bits;
+       dest = (ipc_object_t) kmsg->ikm_header->msgh_remote_port;
+       reply = (ipc_object_t) kmsg->ikm_header->msgh_local_port;
        dest_type = MACH_MSGH_BITS_REMOTE(mbits);
        reply_type = MACH_MSGH_BITS_LOCAL(mbits);
 
@@ -2551,18 +2940,20 @@ ipc_kmsg_copyout_dest(
        } else
                reply_name = (mach_port_name_t) reply;
 
-       kmsg->ikm_header.msgh_bits = (MACH_MSGH_BITS_OTHER(mbits) |
+       kmsg->ikm_header->msgh_bits = (MACH_MSGH_BITS_OTHER(mbits) |
                                      MACH_MSGH_BITS(reply_type, dest_type));
-       kmsg->ikm_header.msgh_local_port = (ipc_port_t)dest_name;
-       kmsg->ikm_header.msgh_remote_port = (ipc_port_t)reply_name;
+       kmsg->ikm_header->msgh_local_port = (ipc_port_t)dest_name;
+       kmsg->ikm_header->msgh_remote_port = (ipc_port_t)reply_name;
 
        if (mbits & MACH_MSGH_BITS_COMPLEX) {
                mach_msg_body_t *body;
 
-               body = (mach_msg_body_t *) (&kmsg->ikm_header + 1);
-               ipc_kmsg_clean_body(kmsg, body->msgh_descriptor_count);
+               body = (mach_msg_body_t *) (kmsg->ikm_header + 1);
+               ipc_kmsg_clean_body(kmsg, body->msgh_descriptor_count, 
+                                   (mach_msg_descriptor_t *)(body + 1));
        }
 }
+
 /*
  *      Routine:        ipc_kmsg_copyin_scatter
  *      Purpose:
@@ -2588,10 +2979,10 @@ ipc_kmsg_copyout_dest(
  */
 
 mach_msg_body_t *
-ipc_kmsg_copyin_scatter(
-        mach_msg_header_t       *msg,
-        mach_msg_size_t         slist_size,
-        ipc_kmsg_t              kmsg)
+ipc_kmsg_get_scatter(
+       mach_vm_address_t       msg_addr,
+       mach_msg_size_t         slist_size,
+       ipc_kmsg_t              kmsg)
 {
         mach_msg_body_t         *slist;
         mach_msg_body_t         *body;
@@ -2607,18 +2998,18 @@ ipc_kmsg_copyin_scatter(
         if (slist == MACH_MSG_BODY_NULL)
                 return slist;
 
-        if (copyin((char *) (msg + 1), (char *)slist, slist_size)) {
-                kfree((vm_offset_t)slist, slist_size);
+        if (copyin(msg_addr + sizeof(mach_msg_header_t), (char *)slist, slist_size)) {
+                kfree(slist, slist_size);
                 return MACH_MSG_BODY_NULL;
         }
 
         if ((slist->msgh_descriptor_count* sizeof(mach_msg_descriptor_t)
              + sizeof(mach_msg_size_t)) > slist_size) {
-                kfree((vm_offset_t)slist, slist_size);
+                kfree(slist, slist_size);
                 return MACH_MSG_BODY_NULL;
         }
 
-        body = (mach_msg_body_t *) (&kmsg->ikm_header + 1);
+        body = (mach_msg_body_t *) (kmsg->ikm_header + 1);
         gstart = (mach_msg_descriptor_t *) (body + 1);
         gend = gstart + body->msgh_descriptor_count;
 
@@ -2640,7 +3031,7 @@ ipc_kmsg_copyin_scatter(
               * automatic size mismatch.
               */
              if (slist->msgh_descriptor_count == 0) {
-                        kfree((vm_offset_t)slist, slist_size);
+                        kfree(slist, slist_size);
                         return MACH_MSG_BODY_NULL;
              }
 
@@ -2667,23 +3058,23 @@ ipc_kmsg_copyin_scatter(
                     g_type == MACH_MSG_OOL_VOLATILE_DESCRIPTOR) {
                     if (sstart->type.type != MACH_MSG_OOL_DESCRIPTOR &&
                         sstart->type.type != MACH_MSG_OOL_VOLATILE_DESCRIPTOR) {
-                        kfree((vm_offset_t)slist, slist_size);
+                        kfree(slist, slist_size);
                         return MACH_MSG_BODY_NULL;
                     }
                     if (sstart->out_of_line.copy == MACH_MSG_OVERWRITE &&
                         gstart->out_of_line.size > sstart->out_of_line.size) {
-                        kfree((vm_offset_t)slist, slist_size);
+                        kfree(slist, slist_size);
                         return MACH_MSG_BODY_NULL;
                     }
                 }
                 else {
                  if (sstart->type.type != MACH_MSG_OOL_PORTS_DESCRIPTOR) {
-                        kfree((vm_offset_t)slist, slist_size);
+                        kfree(slist, slist_size);
                         return MACH_MSG_BODY_NULL;
                  }
                     if (sstart->ool_ports.copy == MACH_MSG_OVERWRITE &&
                         gstart->ool_ports.count > sstart->ool_ports.count) {
-                        kfree((vm_offset_t)slist, slist_size);
+                        kfree(slist, slist_size);
                         return MACH_MSG_BODY_NULL;
                     }
                 }
@@ -2709,7 +3100,7 @@ ipc_kmsg_free_scatter(
         mach_msg_size_t slist_size)
 {
         slist_size -= sizeof(mach_msg_header_t);
-        kfree((vm_offset_t)slist, slist_size);
+        kfree(slist, slist_size);
 }
 
 
@@ -2737,10 +3128,10 @@ ipc_kmsg_copyout_to_kernel(
        mach_msg_type_name_t reply_type;
        mach_port_name_t dest_name, reply_name;
 
-       dest = (ipc_object_t) kmsg->ikm_header.msgh_remote_port;
-       reply = (ipc_object_t) kmsg->ikm_header.msgh_local_port;
-       dest_type = MACH_MSGH_BITS_REMOTE(kmsg->ikm_header.msgh_bits);
-       reply_type = MACH_MSGH_BITS_LOCAL(kmsg->ikm_header.msgh_bits);
+       dest = (ipc_object_t) kmsg->ikm_header->msgh_remote_port;
+       reply = (ipc_object_t) kmsg->ikm_header->msgh_local_port;
+       dest_type = MACH_MSGH_BITS_REMOTE(kmsg->ikm_header->msgh_bits);
+       reply_type = MACH_MSGH_BITS_LOCAL(kmsg->ikm_header->msgh_bits);
 
        assert(IO_VALID(dest));
 
@@ -2756,11 +3147,11 @@ ipc_kmsg_copyout_to_kernel(
 
        reply_name = (mach_port_name_t) reply;
 
-       kmsg->ikm_header.msgh_bits =
-               (MACH_MSGH_BITS_OTHER(kmsg->ikm_header.msgh_bits) |
+       kmsg->ikm_header->msgh_bits =
+               (MACH_MSGH_BITS_OTHER(kmsg->ikm_header->msgh_bits) |
                                        MACH_MSGH_BITS(reply_type, dest_type));
-       kmsg->ikm_header.msgh_local_port = (ipc_port_t)dest_name;
-       kmsg->ikm_header.msgh_remote_port = (ipc_port_t)reply_name;
+       kmsg->ikm_header->msgh_local_port = (ipc_port_t)dest_name;
+       kmsg->ikm_header->msgh_remote_port = (ipc_port_t)reply_name;
 }
 
 #include <mach_kdb.h>
@@ -2774,25 +3165,25 @@ ipc_kmsg_copyout_to_kernel(
 void ipc_msg_print_untyped(
        mach_msg_body_t         *body);
 
-char * ipc_type_name(
+const char * ipc_type_name(
        int             type_name,
        boolean_t       received);
 
 void ipc_print_type_name(
        int     type_name);
 
-char *
+const char *
 msgh_bit_decode(
        mach_msg_bits_t bit);
 
-char *
+const char *
 mm_copy_options_string(
        mach_msg_copy_options_t option);
 
 void db_print_msg_uid(mach_msg_header_t *);
 
 
-char *
+const char *
 ipc_type_name(
        int             type_name,
        boolean_t       received)
@@ -2840,7 +3231,7 @@ void
 ipc_print_type_name(
        int     type_name)
 {
-       char *name = ipc_type_name(type_name, TRUE);
+       const char *name = ipc_type_name(type_name, TRUE);
        if (name) {
                printf("%s", name);
        } else {
@@ -2861,10 +3252,10 @@ ipc_kmsg_print(
                kmsg->ikm_prev,
                kmsg->ikm_size);
        printf("\n");
-       ipc_msg_print(&kmsg->ikm_header);
+       ipc_msg_print(kmsg->ikm_header);
 }
 
-char *
+const char *
 msgh_bit_decode(
        mach_msg_bits_t bit)
 {
@@ -2884,7 +3275,7 @@ ipc_msg_print(
 {
        mach_msg_bits_t mbits;
        unsigned int    bit, i;
-       char            *bit_name;
+       const char      *bit_name;
        int             needs_comma;
 
        mbits = msgh->msgh_bits;
@@ -2943,11 +3334,11 @@ ipc_msg_print(
 }
 
 
-char *
+const char *
 mm_copy_options_string(
        mach_msg_copy_options_t option)
 {
-       char    *name;
+       const char      *name;
 
        switch (option) {
            case MACH_MSG_PHYSICAL_COPY: