/* * Copyright (c) 2000-2005 Apple Computer, Inc. All rights reserved. * * @APPLE_LICENSE_HEADER_START@ * * The contents of this file constitute Original Code as defined in and * are subject to the Apple Public Source License Version 1.1 (the * "License"). You may not use this file except in compliance with the * License. Please obtain a copy of the License at * http://www.apple.com/publicsource and read it before using this file. * * This 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 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 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. */ /* */ /* * File: ipc/mach_msg.c * Author: Rich Draves * Date: 1989 * * Exported message traps. See mach/message.h. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifndef offsetof #define offsetof(type, member) ((size_t)(&((type *)0)->member)) #endif /* offsetof */ /* * Forward declarations - kernel internal routines */ mach_msg_return_t mach_msg_send( mach_msg_header_t *msg, mach_msg_option_t option, mach_msg_size_t send_size, mach_msg_timeout_t send_timeout, mach_port_name_t notify); mach_msg_return_t mach_msg_receive( mach_msg_header_t *msg, mach_msg_option_t option, mach_msg_size_t rcv_size, mach_port_name_t rcv_name, mach_msg_timeout_t rcv_timeout, void (*continuation)(mach_msg_return_t), mach_msg_size_t slist_size); mach_msg_return_t mach_msg_receive_results(void); mach_msg_return_t msg_receive_error( ipc_kmsg_t kmsg, mach_vm_address_t msg_addr, mach_msg_option_t option, mach_port_seqno_t seqno, ipc_space_t space); security_token_t KERNEL_SECURITY_TOKEN = KERNEL_SECURITY_TOKEN_VALUE; audit_token_t KERNEL_AUDIT_TOKEN = KERNEL_AUDIT_TOKEN_VALUE; mach_msg_format_0_trailer_t trailer_template = { /* mach_msg_trailer_type_t */ MACH_MSG_TRAILER_FORMAT_0, /* mach_msg_trailer_size_t */ MACH_MSG_TRAILER_MINIMUM_SIZE, /* mach_port_seqno_t */ 0, /* security_token_t */ KERNEL_SECURITY_TOKEN_VALUE }; /* * Routine: mach_msg_send * Purpose: * Send a message. * Conditions: * Nothing locked. * Returns: * MACH_MSG_SUCCESS Sent the message. * MACH_SEND_MSG_TOO_SMALL Message smaller than a header. * MACH_SEND_NO_BUFFER Couldn't allocate buffer. * MACH_SEND_INVALID_DATA Couldn't copy message data. * MACH_SEND_INVALID_HEADER * Illegal value in the message header bits. * MACH_SEND_INVALID_DEST The space is dead. * MACH_SEND_INVALID_NOTIFY Bad notify port. * MACH_SEND_INVALID_DEST Can't copyin destination port. * MACH_SEND_INVALID_REPLY Can't copyin reply port. * MACH_SEND_TIMED_OUT Timeout expired without delivery. * MACH_SEND_INTERRUPTED Delivery interrupted. * MACH_SEND_NO_NOTIFY Can't allocate a msg-accepted request. * MACH_SEND_WILL_NOTIFY Msg-accepted notif. requested. * MACH_SEND_NOTIFY_IN_PROGRESS * This space has already forced a message to this port. */ mach_msg_return_t mach_msg_send( mach_msg_header_t *msg, mach_msg_option_t option, mach_msg_size_t send_size, mach_msg_timeout_t send_timeout, mach_port_name_t notify) { ipc_space_t space = current_space(); vm_map_t map = current_map(); ipc_kmsg_t kmsg; mach_msg_return_t mr; mach_msg_size_t msg_and_trailer_size; mach_msg_max_trailer_t *trailer; if ((send_size < sizeof(mach_msg_header_t)) || (send_size & 3)) return MACH_SEND_MSG_TOO_SMALL; msg_and_trailer_size = send_size + MAX_TRAILER_SIZE; kmsg = ipc_kmsg_alloc(msg_and_trailer_size); if (kmsg == IKM_NULL) return MACH_SEND_NO_BUFFER; (void) memcpy((void *) kmsg->ikm_header, (const void *) msg, send_size); kmsg->ikm_header->msgh_size = send_size; /* * reserve for the trailer the largest space (MAX_TRAILER_SIZE) * However, the internal size field of the trailer (msgh_trailer_size) * is initialized to the minimum (sizeof(mach_msg_trailer_t)), to optimize * the cases where no implicit data is requested. */ trailer = (mach_msg_max_trailer_t *) ((vm_offset_t)kmsg->ikm_header + send_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; if (option & MACH_SEND_CANCEL) { if (notify == MACH_PORT_NULL) mr = MACH_SEND_INVALID_NOTIFY; else mr = ipc_kmsg_copyin(kmsg, space, map, notify); } else mr = ipc_kmsg_copyin(kmsg, space, map, MACH_PORT_NULL); if (mr != MACH_MSG_SUCCESS) { ipc_kmsg_free(kmsg); return mr; } mr = ipc_kmsg_send(kmsg, option & MACH_SEND_TIMEOUT, send_timeout); if (mr != MACH_MSG_SUCCESS) { mr |= ipc_kmsg_copyout_pseudo(kmsg, space, map, MACH_MSG_BODY_NULL); (void) memcpy((void *) msg, (const void *) kmsg->ikm_header, kmsg->ikm_header->msgh_size); ipc_kmsg_free(kmsg); } return mr; } /* * Routine: mach_msg_receive * Purpose: * Receive a message. * Conditions: * Nothing locked. * Returns: * MACH_MSG_SUCCESS Received a message. * MACH_RCV_INVALID_NAME The name doesn't denote a right, * or the denoted right is not receive or port set. * MACH_RCV_IN_SET Receive right is a member of a set. * MACH_RCV_TOO_LARGE Message wouldn't fit into buffer. * MACH_RCV_TIMED_OUT Timeout expired without a message. * MACH_RCV_INTERRUPTED Reception interrupted. * MACH_RCV_PORT_DIED Port/set died while receiving. * MACH_RCV_PORT_CHANGED Port moved into set while receiving. * MACH_RCV_INVALID_DATA Couldn't copy to user buffer. * MACH_RCV_INVALID_NOTIFY Bad notify port. * MACH_RCV_HEADER_ERROR */ mach_msg_return_t mach_msg_receive_results(void) { thread_t self = current_thread(); ipc_space_t space = current_space(); vm_map_t map = current_map(); ipc_object_t object = self->ith_object; mach_msg_return_t mr = self->ith_state; mach_vm_address_t msg_addr = self->ith_msg_addr; mach_msg_option_t option = self->ith_option; ipc_kmsg_t kmsg = self->ith_kmsg; mach_port_seqno_t seqno = self->ith_seqno; mach_msg_format_0_trailer_t *trailer; ipc_object_release(object); if (mr != MACH_MSG_SUCCESS) { if (mr == MACH_RCV_TOO_LARGE ) { if (option & MACH_RCV_LARGE) { /* * We need to inform the user-level code that it needs more * space. The value for how much space was returned in the * msize save area instead of the message (which was left on * the queue). */ if (copyout((char *) &self->ith_msize, msg_addr + offsetof(mach_msg_header_t, msgh_size), sizeof(mach_msg_size_t))) mr = MACH_RCV_INVALID_DATA; goto out; } if (msg_receive_error(kmsg, msg_addr, option, seqno, space) == MACH_RCV_INVALID_DATA) mr = MACH_RCV_INVALID_DATA; } goto out; } trailer = (mach_msg_format_0_trailer_t *) ((vm_offset_t)kmsg->ikm_header + round_msg(kmsg->ikm_header->msgh_size)); if (option & MACH_RCV_TRAILER_MASK) { trailer->msgh_seqno = seqno; trailer->msgh_trailer_size = REQUESTED_TRAILER_SIZE(option); } /* * If MACH_RCV_OVERWRITE was specified, try to get the scatter * list and verify it against the contents of the message. If * there is any problem with it, we will continue without it as * normal. */ if (option & MACH_RCV_OVERWRITE) { mach_msg_size_t slist_size = self->ith_scatter_list_size; mach_msg_body_t *slist; slist = ipc_kmsg_get_scatter(msg_addr, slist_size, kmsg); mr = ipc_kmsg_copyout(kmsg, space, map, MACH_PORT_NULL, slist); ipc_kmsg_free_scatter(slist, slist_size); } else { mr = ipc_kmsg_copyout(kmsg, space, map, MACH_PORT_NULL, MACH_MSG_BODY_NULL); } if (mr != MACH_MSG_SUCCESS) { if ((mr &~ MACH_MSG_MASK) == MACH_RCV_BODY_ERROR) { if (ipc_kmsg_put(msg_addr, kmsg, kmsg->ikm_header->msgh_size + trailer->msgh_trailer_size) == MACH_RCV_INVALID_DATA) mr = MACH_RCV_INVALID_DATA; } else { if (msg_receive_error(kmsg, msg_addr, option, seqno, space) == MACH_RCV_INVALID_DATA) mr = MACH_RCV_INVALID_DATA; } goto out; } mr = ipc_kmsg_put(msg_addr, kmsg, kmsg->ikm_header->msgh_size + trailer->msgh_trailer_size); out: return mr; } mach_msg_return_t mach_msg_receive( mach_msg_header_t *msg, mach_msg_option_t option, mach_msg_size_t rcv_size, mach_port_name_t rcv_name, mach_msg_timeout_t rcv_timeout, void (*continuation)(mach_msg_return_t), mach_msg_size_t slist_size) { thread_t self = current_thread(); ipc_space_t space = current_space(); ipc_object_t object; ipc_mqueue_t mqueue; mach_msg_return_t mr; mr = ipc_mqueue_copyin(space, rcv_name, &mqueue, &object); if (mr != MACH_MSG_SUCCESS) { return mr; } /* hold ref for object */ self->ith_msg_addr = CAST_DOWN(mach_vm_address_t, msg); self->ith_object = object; self->ith_msize = rcv_size; self->ith_option = option; self->ith_scatter_list_size = slist_size; self->ith_continuation = continuation; ipc_mqueue_receive(mqueue, option, rcv_size, rcv_timeout, THREAD_ABORTSAFE); if ((option & MACH_RCV_TIMEOUT) && rcv_timeout == 0) thread_poll_yield(self); return mach_msg_receive_results(); } void mach_msg_receive_continue(void) { thread_t self = current_thread(); (*self->ith_continuation)(mach_msg_receive_results()); } /* * Toggle this to compile the hotpath in/out * If compiled in, the run-time toggle "enable_hotpath" below * eases testing & debugging */ #define ENABLE_HOTPATH 1 /* Hacked on for now */ #if ENABLE_HOTPATH /* * These counters allow tracing of hotpath behavior under test loads. * A couple key counters are unconditional (see below). */ #define HOTPATH_DEBUG 0 /* Toggle to include lots of counters */ #if HOTPATH_DEBUG #define HOT(expr) expr unsigned int c_mmot_FIRST = 0; /* Unused First Counter */ unsigned int c_mmot_combined_S_R = 0; /* hotpath candidates */ unsigned int c_mach_msg_trap_switch_fast = 0; /* hotpath successes */ unsigned int c_mmot_kernel_send = 0; /* kernel server */ unsigned int c_mmot_cold_000 = 0; /* see below ... */ unsigned int c_mmot_smallsendsize = 0; unsigned int c_mmot_oddsendsize = 0; unsigned int c_mmot_bigsendsize = 0; unsigned int c_mmot_copyinmsg_fail = 0; unsigned int c_mmot_g_slow_copyin3 = 0; unsigned int c_mmot_cold_006 = 0; unsigned int c_mmot_cold_007 = 0; unsigned int c_mmot_cold_008 = 0; unsigned int c_mmot_cold_009 = 0; unsigned int c_mmot_cold_010 = 0; unsigned int c_mmot_cold_012 = 0; unsigned int c_mmot_cold_013 = 0; unsigned int c_mmot_cold_014 = 0; unsigned int c_mmot_cold_016 = 0; unsigned int c_mmot_cold_018 = 0; unsigned int c_mmot_cold_019 = 0; unsigned int c_mmot_cold_020 = 0; unsigned int c_mmot_cold_021 = 0; unsigned int c_mmot_cold_022 = 0; unsigned int c_mmot_cold_023 = 0; unsigned int c_mmot_cold_024 = 0; unsigned int c_mmot_cold_025 = 0; unsigned int c_mmot_cold_026 = 0; unsigned int c_mmot_cold_027 = 0; unsigned int c_mmot_hot_fSR_ok = 0; unsigned int c_mmot_cold_029 = 0; unsigned int c_mmot_cold_030 = 0; unsigned int c_mmot_cold_031 = 0; unsigned int c_mmot_cold_032 = 0; unsigned int c_mmot_cold_033 = 0; unsigned int c_mmot_bad_rcvr = 0; unsigned int c_mmot_rcvr_swapped = 0; unsigned int c_mmot_rcvr_locked = 0; unsigned int c_mmot_rcvr_tswapped = 0; unsigned int c_mmot_rcvr_freed = 0; unsigned int c_mmot_g_slow_copyout6 = 0; unsigned int c_mmot_g_slow_copyout5 = 0; unsigned int c_mmot_cold_037 = 0; unsigned int c_mmot_cold_038 = 0; unsigned int c_mmot_cold_039 = 0; unsigned int c_mmot_g_slow_copyout4 = 0; unsigned int c_mmot_g_slow_copyout3 = 0; unsigned int c_mmot_hot_ok1 = 0; unsigned int c_mmot_hot_ok2 = 0; unsigned int c_mmot_hot_ok3 = 0; unsigned int c_mmot_g_slow_copyout1 = 0; unsigned int c_mmot_g_slow_copyout2 = 0; unsigned int c_mmot_getback_fast_copyin = 0; unsigned int c_mmot_cold_048 = 0; unsigned int c_mmot_getback_FastSR = 0; unsigned int c_mmot_cold_050 = 0; unsigned int c_mmot_cold_051 = 0; unsigned int c_mmot_cold_052 = 0; unsigned int c_mmot_cold_053 = 0; unsigned int c_mmot_fastkernelreply = 0; unsigned int c_mmot_cold_055 = 0; unsigned int c_mmot_getback_fast_put = 0; unsigned int c_mmot_LAST = 0; /* End Marker - Unused */ void db_mmot_zero_counters(void); /* forward; */ void db_mmot_show_counters(void); /* forward; */ void /* Call from the debugger to clear all counters */ db_mmot_zero_counters(void) { register unsigned int *ip = &c_mmot_FIRST; while (ip <= &c_mmot_LAST) *ip++ = 0; } void /* Call from the debugger to show all counters */ db_mmot_show_counters(void) { #define xx(str) printf("%s: %d\n", # str, str); xx(c_mmot_combined_S_R); xx(c_mach_msg_trap_switch_fast); xx(c_mmot_kernel_send); xx(c_mmot_cold_000); xx(c_mmot_smallsendsize); xx(c_mmot_oddsendsize); xx(c_mmot_bigsendsize); xx(c_mmot_copyinmsg_fail); xx(c_mmot_g_slow_copyin3); xx(c_mmot_cold_006); xx(c_mmot_cold_007); xx(c_mmot_cold_008); xx(c_mmot_cold_009); xx(c_mmot_cold_010); xx(c_mmot_cold_012); xx(c_mmot_cold_013); xx(c_mmot_cold_014); xx(c_mmot_cold_016); xx(c_mmot_cold_018); xx(c_mmot_cold_019); xx(c_mmot_cold_020); xx(c_mmot_cold_021); xx(c_mmot_cold_022); xx(c_mmot_cold_023); xx(c_mmot_cold_024); xx(c_mmot_cold_025); xx(c_mmot_cold_026); xx(c_mmot_cold_027); xx(c_mmot_hot_fSR_ok); xx(c_mmot_cold_029); xx(c_mmot_cold_030); xx(c_mmot_cold_031); xx(c_mmot_cold_032); xx(c_mmot_cold_033); xx(c_mmot_bad_rcvr); xx(c_mmot_rcvr_swapped); xx(c_mmot_rcvr_locked); xx(c_mmot_rcvr_tswapped); xx(c_mmot_rcvr_freed); xx(c_mmot_g_slow_copyout6); xx(c_mmot_g_slow_copyout5); xx(c_mmot_cold_037); xx(c_mmot_cold_038); xx(c_mmot_cold_039); xx(c_mmot_g_slow_copyout4); xx(c_mmot_g_slow_copyout3); xx(c_mmot_g_slow_copyout1); xx(c_mmot_hot_ok3); xx(c_mmot_hot_ok2); xx(c_mmot_hot_ok1); xx(c_mmot_g_slow_copyout2); xx(c_mmot_getback_fast_copyin); xx(c_mmot_cold_048); xx(c_mmot_getback_FastSR); xx(c_mmot_cold_050); xx(c_mmot_cold_051); xx(c_mmot_cold_052); xx(c_mmot_cold_053); xx(c_mmot_fastkernelreply); xx(c_mmot_cold_055); xx(c_mmot_getback_fast_put); #undef xx } #else /* !HOTPATH_DEBUG */ /* * Duplicate just these few so we can always do a quick sanity check */ unsigned int c_mmot_combined_S_R = 0; /* hotpath candidates */ unsigned int c_mach_msg_trap_switch_fast = 0; /* hotpath successes */ unsigned int c_mmot_kernel_send = 0; /* kernel server calls */ #define HOT(expr) /* no optional counters */ #endif /* !HOTPATH_DEBUG */ boolean_t enable_hotpath = TRUE; /* Patchable, just in case ... */ #endif /* HOTPATH_ENABLE */ /* * Routine: mach_msg_overwrite_trap [mach trap] * Purpose: * Possibly send a message; possibly receive a message. * Conditions: * Nothing locked. * Returns: * All of mach_msg_send and mach_msg_receive error codes. */ mach_msg_return_t mach_msg_overwrite_trap( struct mach_msg_overwrite_trap_args *args) { mach_vm_address_t msg_addr = args->msg; mach_msg_option_t option = args->option; mach_msg_size_t send_size = args->send_size; mach_msg_size_t rcv_size = args->rcv_size; mach_port_name_t rcv_name = args->rcv_name; mach_msg_timeout_t msg_timeout = args->timeout; mach_port_name_t notify = args->notify; mach_vm_address_t rcv_msg_addr = args->rcv_msg; mach_msg_size_t scatter_list_size = 0; /* NOT INITIALIZED - but not used in pactice */ register mach_msg_header_t *hdr; mach_msg_return_t mr = MACH_MSG_SUCCESS; /* mask out some of the options before entering the hot path */ mach_msg_option_t masked_option = option & ~(MACH_SEND_TRAILER|MACH_RCV_TRAILER_MASK|MACH_RCV_LARGE); #if ENABLE_HOTPATH /* BEGINNING OF HOT PATH */ if ((masked_option == (MACH_SEND_MSG|MACH_RCV_MSG)) && enable_hotpath) { thread_t self = current_thread(); mach_msg_format_0_trailer_t *trailer; ipc_space_t space = self->task->itk_space; ipc_kmsg_t kmsg; register ipc_port_t dest_port; ipc_object_t rcv_object; ipc_mqueue_t rcv_mqueue; mach_msg_size_t reply_size; c_mmot_combined_S_R++; /* * This case is divided into ten sections, each * with a label. There are five optimized * sections and six unoptimized sections, which * do the same thing but handle all possible * cases and are slower. * * The five sections for an RPC are * 1) Get request message into a buffer. * 2) Copyin request message and rcv_name. * (fast_copyin or slow_copyin) * 3) Enqueue request and dequeue reply. * (fast_send_receive or * slow_send and slow_receive) * 4) Copyout reply message. * (fast_copyout or slow_copyout) * 5) Put reply message to user's buffer. * * Keep the locking hierarchy firmly in mind. * (First spaces, then ports, then port sets, * then message queues.) Only a non-blocking * attempt can be made to acquire locks out of * order, or acquire two locks on the same level. * Acquiring two locks on the same level will * fail if the objects are really the same, * unless simple locking is disabled. This is OK, * because then the extra unlock does nothing. * * There are two major reasons these RPCs can't use * ipc_thread_switch, and use slow_send/slow_receive: * 1) Kernel RPCs. * 2) Servers fall behind clients, so * client doesn't find a blocked server thread and * server finds waiting messages and can't block. */ mr = ipc_kmsg_get(msg_addr, send_size, &kmsg); if (mr != KERN_SUCCESS) { return mr; } hdr = kmsg->ikm_header; trailer = (mach_msg_format_0_trailer_t *) ((vm_offset_t) hdr + send_size); /* * fast_copyin: * * optimized ipc_kmsg_copyin/ipc_mqueue_copyin * * We have the request message data in kmsg. * Must still do copyin, send, receive, etc. * * If the message isn't simple, we can't combine * ipc_kmsg_copyin_header and ipc_mqueue_copyin, * because copyin of the message body might * affect rcv_name. */ switch (hdr->msgh_bits) { case MACH_MSGH_BITS(MACH_MSG_TYPE_COPY_SEND, MACH_MSG_TYPE_MAKE_SEND_ONCE): { register ipc_entry_t table; register ipc_entry_num_t size; register ipc_port_t reply_port; /* sending a request message */ { register mach_port_index_t index; register mach_port_gen_t gen; { register mach_port_name_t reply_name = (mach_port_name_t)hdr->msgh_local_port; if (reply_name != rcv_name) { HOT(c_mmot_g_slow_copyin3++); goto slow_copyin; } /* optimized ipc_entry_lookup of reply_name */ index = MACH_PORT_INDEX(reply_name); gen = MACH_PORT_GEN(reply_name); is_read_lock(space); assert(space->is_active); size = space->is_table_size; table = space->is_table; { register ipc_entry_t entry; register ipc_entry_bits_t bits; if (index < size) { entry = &table[index]; bits = entry->ie_bits; if (IE_BITS_GEN(bits) != gen || (bits & IE_BITS_COLLISION)) { entry = IE_NULL; } } else { entry = IE_NULL; bits = 0; } if (entry == IE_NULL) { entry = ipc_entry_lookup(space, reply_name); if (entry == IE_NULL) { HOT(c_mmot_cold_006++); goto abort_request_copyin; } bits = entry->ie_bits; } /* check type bit */ if (! (bits & MACH_PORT_TYPE_RECEIVE)) { HOT(c_mmot_cold_007++); goto abort_request_copyin; } reply_port = (ipc_port_t) entry->ie_object; assert(reply_port != IP_NULL); } } } /* optimized ipc_entry_lookup of dest_name */ { register mach_port_index_t index; register mach_port_gen_t gen; { register mach_port_name_t dest_name = (mach_port_name_t)hdr->msgh_remote_port; index = MACH_PORT_INDEX(dest_name); gen = MACH_PORT_GEN(dest_name); { register ipc_entry_t entry; register ipc_entry_bits_t bits; if (index < size) { entry = &table[index]; bits = entry->ie_bits; if (IE_BITS_GEN(bits) != gen || (bits & IE_BITS_COLLISION)) { entry = IE_NULL; } } else { entry = IE_NULL; bits = 0; } if (entry == IE_NULL) { entry = ipc_entry_lookup(space, dest_name); if (entry == IE_NULL) { HOT(c_mmot_cold_008++); goto abort_request_copyin; } bits = entry->ie_bits; } /* check type bit */ if (! (bits & MACH_PORT_TYPE_SEND)) { HOT(c_mmot_cold_009++); goto abort_request_copyin; } assert(IE_BITS_UREFS(bits) > 0); dest_port = (ipc_port_t) entry->ie_object; assert(dest_port != IP_NULL); } } } /* * To do an atomic copyin, need simultaneous * locks on both ports and the space. If * dest_port == reply_port, and simple locking is * enabled, then we will abort. Otherwise it's * OK to unlock twice. */ ip_lock(dest_port); if (!ip_active(dest_port) || !ip_lock_try(reply_port)) { ip_unlock(dest_port); HOT(c_mmot_cold_010++); goto abort_request_copyin; } is_read_unlock(space); assert(dest_port->ip_srights > 0); dest_port->ip_srights++; ip_reference(dest_port); assert(ip_active(reply_port)); assert(reply_port->ip_receiver_name == (mach_port_name_t)hdr->msgh_local_port); assert(reply_port->ip_receiver == space); reply_port->ip_sorights++; ip_reference(reply_port); hdr->msgh_bits = MACH_MSGH_BITS(MACH_MSG_TYPE_PORT_SEND, MACH_MSG_TYPE_PORT_SEND_ONCE); hdr->msgh_remote_port = dest_port; hdr->msgh_local_port = reply_port; /* make sure we can queue to the destination */ if (dest_port->ip_receiver == ipc_space_kernel) { /* * The kernel server has a reference to * the reply port, which it hands back * to us in the reply message. We do * not need to keep another reference to * it. */ ip_unlock(reply_port); assert(ip_active(dest_port)); dest_port->ip_messages.imq_seqno++; ip_unlock(dest_port); goto kernel_send; } if (imq_full(&dest_port->ip_messages)) { HOT(c_mmot_cold_013++); goto abort_request_send_receive; } /* optimized ipc_mqueue_copyin */ rcv_object = (ipc_object_t) reply_port; io_reference(rcv_object); rcv_mqueue = &reply_port->ip_messages; io_unlock(rcv_object); HOT(c_mmot_hot_fSR_ok++); goto fast_send_receive; abort_request_copyin: is_read_unlock(space); goto slow_copyin; abort_request_send_receive: ip_unlock(dest_port); ip_unlock(reply_port); goto slow_send; } case MACH_MSGH_BITS(MACH_MSG_TYPE_MOVE_SEND_ONCE, 0): { register ipc_entry_num_t size; register ipc_entry_t table; /* sending a reply message */ { register mach_port_name_t reply_name = (mach_port_name_t)hdr->msgh_local_port; if (reply_name != MACH_PORT_NULL) { HOT(c_mmot_cold_018++); goto slow_copyin; } } is_write_lock(space); assert(space->is_active); /* optimized ipc_entry_lookup */ size = space->is_table_size; table = space->is_table; { register ipc_entry_t entry; register mach_port_gen_t gen; register mach_port_index_t index; { register mach_port_name_t dest_name = (mach_port_name_t)hdr->msgh_remote_port; index = MACH_PORT_INDEX(dest_name); gen = MACH_PORT_GEN(dest_name); } if (index >= size) { HOT(c_mmot_cold_019++); goto abort_reply_dest_copyin; } entry = &table[index]; /* check generation, collision bit, and type bit */ if ((entry->ie_bits & (IE_BITS_GEN_MASK| IE_BITS_COLLISION| MACH_PORT_TYPE_SEND_ONCE)) != (gen | MACH_PORT_TYPE_SEND_ONCE)) { HOT(c_mmot_cold_020++); goto abort_reply_dest_copyin; } /* optimized ipc_right_copyin */ assert(IE_BITS_TYPE(entry->ie_bits) == MACH_PORT_TYPE_SEND_ONCE); assert(IE_BITS_UREFS(entry->ie_bits) == 1); if (entry->ie_request != 0) { HOT(c_mmot_cold_021++); goto abort_reply_dest_copyin; } dest_port = (ipc_port_t) entry->ie_object; assert(dest_port != IP_NULL); ip_lock(dest_port); if (!ip_active(dest_port)) { ip_unlock(dest_port); HOT(c_mmot_cold_022++); goto abort_reply_dest_copyin; } assert(dest_port->ip_sorights > 0); /* optimized ipc_entry_dealloc */ entry->ie_bits = gen; entry->ie_next = table->ie_next; table->ie_next = index; entry->ie_object = IO_NULL; } hdr->msgh_bits = MACH_MSGH_BITS(MACH_MSG_TYPE_PORT_SEND_ONCE, 0); hdr->msgh_remote_port = dest_port; /* make sure we can queue to the destination */ assert(dest_port->ip_receiver != ipc_space_kernel); /* optimized ipc_entry_lookup/ipc_mqueue_copyin */ { register ipc_entry_t entry; register ipc_entry_bits_t bits; { register mach_port_index_t index; register mach_port_gen_t gen; index = MACH_PORT_INDEX(rcv_name); gen = MACH_PORT_GEN(rcv_name); if (index < size) { entry = &table[index]; bits = entry->ie_bits; if (IE_BITS_GEN(bits) != gen || (bits & IE_BITS_COLLISION)) { entry = IE_NULL; } } else { entry = IE_NULL; bits = 0; } if (entry == IE_NULL) { entry = ipc_entry_lookup(space, rcv_name); if (entry == IE_NULL) { HOT(c_mmot_cold_024++); goto abort_reply_rcv_copyin; } bits = entry->ie_bits; } } /* check type bits; looking for receive or set */ #if 0 /* * JMM - The check below for messages in the receive * mqueue is insufficient to work with port sets, since * the messages stay in the port queues. For now, don't * allow portsets (but receiving on portsets when sending * a message to a send-once right is actually a very * common case (so we should re-enable). */ if (bits & MACH_PORT_TYPE_PORT_SET) { register ipc_pset_t rcv_pset; rcv_pset = (ipc_pset_t) entry->ie_object; assert(rcv_pset != IPS_NULL); ips_lock(rcv_pset); assert(ips_active(rcv_pset)); rcv_object = (ipc_object_t) rcv_pset; rcv_mqueue = &rcv_pset->ips_messages; } else #endif /* 0 */ if (bits & MACH_PORT_TYPE_RECEIVE) { register ipc_port_t rcv_port; rcv_port = (ipc_port_t) entry->ie_object; assert(rcv_port != IP_NULL); if (!ip_lock_try(rcv_port)) { HOT(c_mmot_cold_025++); goto abort_reply_rcv_copyin; } assert(ip_active(rcv_port)); if (rcv_port->ip_pset_count != 0) { ip_unlock(rcv_port); HOT(c_mmot_cold_026++); goto abort_reply_rcv_copyin; } rcv_object = (ipc_object_t) rcv_port; rcv_mqueue = &rcv_port->ip_messages; } else { HOT(c_mmot_cold_027++); goto abort_reply_rcv_copyin; } } is_write_unlock(space); io_reference(rcv_object); io_unlock(rcv_object); HOT(c_mmot_hot_fSR_ok++); goto fast_send_receive; abort_reply_dest_copyin: is_write_unlock(space); HOT(c_mmot_cold_029++); goto slow_copyin; abort_reply_rcv_copyin: ip_unlock(dest_port); is_write_unlock(space); HOT(c_mmot_cold_030++); goto slow_send; } default: HOT(c_mmot_cold_031++); goto slow_copyin; } /*NOTREACHED*/ fast_send_receive: /* * optimized ipc_mqueue_send/ipc_mqueue_receive * * Finished get/copyin of kmsg and copyin of rcv_name. * space is unlocked, dest_port is locked, * we can queue kmsg to dest_port, * rcv_mqueue is set, and rcv_object holds a ref * so the mqueue cannot go away. * * JMM - For now, rcv_object is just a port. Portsets * are disabled for the time being. */ assert(ip_active(dest_port)); assert(dest_port->ip_receiver != ipc_space_kernel); // assert(!imq_full(&dest_port->ip_messages) || // (MACH_MSGH_BITS_REMOTE(hdr->msgh_bits) == // MACH_MSG_TYPE_PORT_SEND_ONCE)); assert((hdr->msgh_bits & MACH_MSGH_BITS_CIRCULAR) == 0); { register ipc_mqueue_t dest_mqueue; wait_queue_t waitq; thread_t receiver; processor_t processor; boolean_t still_running; spl_t s; s = splsched(); processor = current_processor(); if (processor->current_pri >= BASEPRI_RTQUEUES) goto abort_send_receive1; dest_mqueue = &dest_port->ip_messages; waitq = &dest_mqueue->imq_wait_queue; imq_lock(dest_mqueue); wait_queue_peek64_locked(waitq, IPC_MQUEUE_RECEIVE, &receiver, &waitq); /* queue still locked, thread locked - but still on q */ if ( receiver == THREAD_NULL ) { abort_send_receive: imq_unlock(dest_mqueue); abort_send_receive1: splx(s); ip_unlock(dest_port); ipc_object_release(rcv_object); HOT(c_mmot_cold_032++); goto slow_send; } assert(receiver->state & TH_WAIT); assert(receiver->wait_queue == waitq); assert(receiver->wait_event == IPC_MQUEUE_RECEIVE); /* * Make sure that the scheduling restrictions of the receiver * are consistent with a handoff here (if it comes down to that). */ if ( receiver->sched_pri >= BASEPRI_RTQUEUES || receiver->processor_set != processor->processor_set || (receiver->bound_processor != PROCESSOR_NULL && receiver->bound_processor != processor)) { HOT(c_mmot_cold_033++); fall_off: thread_unlock(receiver); if (waitq != &dest_mqueue->imq_wait_queue) wait_queue_unlock(waitq); goto abort_send_receive; } /* * Check that the receiver can stay on the hot path. */ if (ipc_kmsg_copyout_size(kmsg, receiver->map) + REQUESTED_TRAILER_SIZE(receiver->ith_option) > receiver->ith_msize) { /* * The receiver can't accept the message. */ HOT(c_mmot_bad_rcvr++); goto fall_off; } /* * Before committing to the handoff, make sure that we are * really going to block (i.e. there are no messages already * queued for us. This violates lock ordering, so make sure * we don't deadlock. After the trylock succeeds below, we * may have up to 3 message queues locked: * - the dest port mqueue * - a portset mqueue (where waiting receiver was found) * - finally our own rcv_mqueue * * JMM - Need to make this check appropriate for portsets as * well before re-enabling them. */ if (!imq_lock_try(rcv_mqueue)) { goto fall_off; } if (ipc_kmsg_queue_first(&rcv_mqueue->imq_messages) != IKM_NULL) { imq_unlock(rcv_mqueue); HOT(c_mmot_cold_033++); goto fall_off; } /* At this point we are committed to do the "handoff". */ c_mach_msg_trap_switch_fast++; /* * Go ahead and pull the receiver from the waitq. If the * waitq wasn't the one for the mqueue, unlock it. */ wait_queue_pull_thread_locked(waitq, receiver, (waitq != &dest_mqueue->imq_wait_queue)); /* * Store the kmsg and seqno where the receiver can pick it up. */ receiver->ith_state = MACH_MSG_SUCCESS; receiver->ith_kmsg = kmsg; receiver->ith_seqno = dest_mqueue->imq_seqno++; /* * Unblock the receiver. If it was still running on another * CPU, we'll give it a chance to run with the message where * it is (and just select someother thread to run here). * Otherwise, we'll invoke it here as part of the handoff. */ still_running = thread_unblock(receiver, THREAD_AWAKENED); thread_unlock(receiver); imq_unlock(dest_mqueue); ip_unlock(dest_port); current_task()->messages_sent++; /* * Put self on receive port's queue. * Also save state that the sender of * our reply message needs to determine if it * can hand off directly back to us. */ thread_lock(self); self->ith_msg_addr = (rcv_msg_addr) ? rcv_msg_addr : msg_addr; self->ith_object = rcv_object; /* still holds reference */ self->ith_msize = rcv_size; self->ith_option = option; self->ith_scatter_list_size = scatter_list_size; self->ith_continuation = thread_syscall_return; waitq = &rcv_mqueue->imq_wait_queue; (void)wait_queue_assert_wait64_locked(waitq, IPC_MQUEUE_RECEIVE, THREAD_ABORTSAFE, 0, self); thread_unlock(self); imq_unlock(rcv_mqueue); /* * If the receiving thread wasn't still running, we switch directly * to it here. Otherwise we let the scheduler pick something for * here. In either case, block this thread as though it had called * ipc_mqueue_receive. */ if (still_running) { splx(s); thread_block(ipc_mqueue_receive_continue); } else { thread_run(self, ipc_mqueue_receive_continue, NULL, receiver); } /* NOTREACHED */ } fast_copyout: /* * Nothing locked and no references held, except * we have kmsg with msgh_seqno filled in. Must * still check against rcv_size and do * ipc_kmsg_copyout/ipc_kmsg_put. */ reply_size = send_size + trailer->msgh_trailer_size; if (rcv_size < reply_size) { HOT(c_mmot_g_slow_copyout6++); goto slow_copyout; } /* optimized ipc_kmsg_copyout/ipc_kmsg_copyout_header */ switch (hdr->msgh_bits) { case MACH_MSGH_BITS(MACH_MSG_TYPE_PORT_SEND, MACH_MSG_TYPE_PORT_SEND_ONCE): { ipc_port_t reply_port = (ipc_port_t) hdr->msgh_local_port; mach_port_name_t dest_name, reply_name; /* receiving a request message */ if (!IP_VALID(reply_port)) { HOT(c_mmot_g_slow_copyout5++); goto slow_copyout; } is_write_lock(space); assert(space->is_active); /* * To do an atomic copyout, need simultaneous * locks on both ports and the space. If * dest_port == reply_port, and simple locking is * enabled, then we will abort. Otherwise it's * OK to unlock twice. */ ip_lock(dest_port); if (!ip_active(dest_port) || !ip_lock_try(reply_port)) { HOT(c_mmot_cold_037++); goto abort_request_copyout; } if (!ip_active(reply_port)) { ip_unlock(reply_port); HOT(c_mmot_cold_038++); goto abort_request_copyout; } assert(reply_port->ip_sorights > 0); ip_unlock(reply_port); { register ipc_entry_t table; register ipc_entry_t entry; register mach_port_index_t index; /* optimized ipc_entry_get */ table = space->is_table; index = table->ie_next; if (index == 0) { HOT(c_mmot_cold_039++); goto abort_request_copyout; } entry = &table[index]; table->ie_next = entry->ie_next; entry->ie_request = 0; { register mach_port_gen_t gen; assert((entry->ie_bits &~ IE_BITS_GEN_MASK) == 0); gen = IE_BITS_NEW_GEN(entry->ie_bits); reply_name = MACH_PORT_MAKE(index, gen); /* optimized ipc_right_copyout */ entry->ie_bits = gen | (MACH_PORT_TYPE_SEND_ONCE | 1); } assert(MACH_PORT_VALID(reply_name)); entry->ie_object = (ipc_object_t) reply_port; is_write_unlock(space); } /* optimized ipc_object_copyout_dest */ assert(dest_port->ip_srights > 0); ip_release(dest_port); if (dest_port->ip_receiver == space) dest_name = dest_port->ip_receiver_name; else dest_name = MACH_PORT_NULL; if ((--dest_port->ip_srights == 0) && (dest_port->ip_nsrequest != IP_NULL)) { ipc_port_t nsrequest; mach_port_mscount_t mscount; /* a rather rare case */ nsrequest = dest_port->ip_nsrequest; mscount = dest_port->ip_mscount; dest_port->ip_nsrequest = IP_NULL; ip_unlock(dest_port); ipc_notify_no_senders(nsrequest, mscount); } else ip_unlock(dest_port); hdr->msgh_bits = MACH_MSGH_BITS(MACH_MSG_TYPE_PORT_SEND_ONCE, MACH_MSG_TYPE_PORT_SEND); hdr->msgh_remote_port = (mach_port_t)reply_name; hdr->msgh_local_port = (mach_port_t)dest_name; HOT(c_mmot_hot_ok1++); goto fast_put; abort_request_copyout: ip_unlock(dest_port); is_write_unlock(space); HOT(c_mmot_g_slow_copyout4++); goto slow_copyout; } case MACH_MSGH_BITS(MACH_MSG_TYPE_PORT_SEND_ONCE, 0): { register mach_port_name_t dest_name; /* receiving a reply message */ ip_lock(dest_port); if (!ip_active(dest_port)) { ip_unlock(dest_port); HOT(c_mmot_g_slow_copyout3++); goto slow_copyout; } /* optimized ipc_object_copyout_dest */ assert(dest_port->ip_sorights > 0); if (dest_port->ip_receiver == space) { ip_release(dest_port); dest_port->ip_sorights--; dest_name = dest_port->ip_receiver_name; ip_unlock(dest_port); } else { ip_unlock(dest_port); ipc_notify_send_once(dest_port); dest_name = MACH_PORT_NULL; } hdr->msgh_bits = MACH_MSGH_BITS(0, MACH_MSG_TYPE_PORT_SEND_ONCE); hdr->msgh_remote_port = MACH_PORT_NULL; hdr->msgh_local_port = (ipc_port_t)dest_name; HOT(c_mmot_hot_ok2++); goto fast_put; } case MACH_MSGH_BITS_COMPLEX| MACH_MSGH_BITS(MACH_MSG_TYPE_PORT_SEND_ONCE, 0): { register mach_port_name_t dest_name; /* receiving a complex reply message */ ip_lock(dest_port); if (!ip_active(dest_port)) { ip_unlock(dest_port); HOT(c_mmot_g_slow_copyout1++); goto slow_copyout; } /* optimized ipc_object_copyout_dest */ assert(dest_port->ip_sorights > 0); if (dest_port->ip_receiver == space) { ip_release(dest_port); dest_port->ip_sorights--; dest_name = dest_port->ip_receiver_name; ip_unlock(dest_port); } else { ip_unlock(dest_port); ipc_notify_send_once(dest_port); dest_name = MACH_PORT_NULL; } hdr->msgh_bits = MACH_MSGH_BITS_COMPLEX | MACH_MSGH_BITS(0, MACH_MSG_TYPE_PORT_SEND_ONCE); hdr->msgh_remote_port = MACH_PORT_NULL; hdr->msgh_local_port = (mach_port_t)dest_name; mr = ipc_kmsg_copyout_body(kmsg, space, current_map(), MACH_MSG_BODY_NULL); /* hdr and send_size may be invalid now - done use */ if (mr != MACH_MSG_SUCCESS) { if (ipc_kmsg_put(msg_addr, kmsg, kmsg->ikm_header->msgh_size + trailer->msgh_trailer_size) == MACH_RCV_INVALID_DATA) return MACH_RCV_INVALID_DATA; else return mr | MACH_RCV_BODY_ERROR; } HOT(c_mmot_hot_ok3++); goto fast_put; } default: HOT(c_mmot_g_slow_copyout2++); goto slow_copyout; } /*NOTREACHED*/ fast_put: mr = ipc_kmsg_put(rcv_msg_addr ? rcv_msg_addr : msg_addr, kmsg, kmsg->ikm_header->msgh_size + trailer->msgh_trailer_size); if (mr != MACH_MSG_SUCCESS) { return MACH_RCV_INVALID_DATA; } current_task()->messages_received++; return mr; /* BEGINNING OF WARM PATH */ /* * The slow path has a few non-register temporary * variables used only for call-by-reference. */ slow_copyin: { mach_port_seqno_t temp_seqno = 0; register mach_port_name_t reply_name = (mach_port_name_t)hdr->msgh_local_port; /* * We have the message data in kmsg, but * we still need to copyin, send it, * receive a reply, and do copyout. */ mr = ipc_kmsg_copyin(kmsg, space, current_map(), MACH_PORT_NULL); if (mr != MACH_MSG_SUCCESS) { ipc_kmsg_free(kmsg); return(mr); } /* * LP64support - We have to recompute the header pointer * and send_size - as they could have changed during the * complex copyin. */ hdr = kmsg->ikm_header; send_size = hdr->msgh_size; /* try to get back on optimized path */ if ((reply_name != rcv_name) || (hdr->msgh_bits & MACH_MSGH_BITS_CIRCULAR)) { HOT(c_mmot_cold_048++); goto slow_send; } dest_port = (ipc_port_t) hdr->msgh_remote_port; assert(IP_VALID(dest_port)); ip_lock(dest_port); if (!ip_active(dest_port)) { ip_unlock(dest_port); goto slow_send; } if (dest_port->ip_receiver == ipc_space_kernel) { dest_port->ip_messages.imq_seqno++; ip_unlock(dest_port); goto kernel_send; } if (!imq_full(&dest_port->ip_messages) || (MACH_MSGH_BITS_REMOTE(hdr->msgh_bits) == MACH_MSG_TYPE_PORT_SEND_ONCE)) { /* * Try an optimized ipc_mqueue_copyin. * It will work if this is a request message. */ register ipc_port_t reply_port; reply_port = (ipc_port_t) hdr->msgh_local_port; if (IP_VALID(reply_port)) { if (ip_lock_try(reply_port)) { if (ip_active(reply_port) && reply_port->ip_receiver == space && reply_port->ip_receiver_name == rcv_name && reply_port->ip_pset_count == 0) { /* Grab a reference to the reply port. */ rcv_object = (ipc_object_t) reply_port; io_reference(rcv_object); rcv_mqueue = &reply_port->ip_messages; io_unlock(rcv_object); HOT(c_mmot_getback_FastSR++); goto fast_send_receive; } ip_unlock(reply_port); } } } ip_unlock(dest_port); HOT(c_mmot_cold_050++); goto slow_send; kernel_send: /* * Special case: send message to kernel services. * The request message has been copied into the * kmsg. Nothing is locked. */ { register ipc_port_t reply_port; mach_port_seqno_t local_seqno; spl_t s; /* * Perform the kernel function. */ c_mmot_kernel_send++; current_task()->messages_sent++; kmsg = ipc_kobject_server(kmsg); if (kmsg == IKM_NULL) { /* * No reply. Take the * slow receive path. */ HOT(c_mmot_cold_051++); goto slow_get_rcv_port; } /* * Check that: * the reply port is alive * we hold the receive right * the name has not changed. * the port is not in a set * If any of these are not true, * we cannot directly receive the reply * message. */ hdr = kmsg->ikm_header; send_size = hdr->msgh_size; trailer = (mach_msg_format_0_trailer_t *) ((vm_offset_t) hdr + round_msg(send_size)); reply_port = (ipc_port_t) hdr->msgh_remote_port; ip_lock(reply_port); if ((!ip_active(reply_port)) || (reply_port->ip_receiver != space) || (reply_port->ip_receiver_name != rcv_name) || (reply_port->ip_pset_count != 0)) { ip_unlock(reply_port); ipc_kmsg_send_always(kmsg); HOT(c_mmot_cold_052++); goto slow_get_rcv_port; } s = splsched(); rcv_mqueue = &reply_port->ip_messages; imq_lock(rcv_mqueue); /* keep port locked, and don`t change ref count yet */ /* * If there are messages on the port * or other threads waiting for a message, * we cannot directly receive the reply. */ if (!wait_queue_empty(&rcv_mqueue->imq_wait_queue) || (ipc_kmsg_queue_first(&rcv_mqueue->imq_messages) != IKM_NULL)) { imq_unlock(rcv_mqueue); splx(s); ip_unlock(reply_port); ipc_kmsg_send_always(kmsg); HOT(c_mmot_cold_053++); goto slow_get_rcv_port; } /* * We can directly receive this reply. * Since there were no messages queued * on the reply port, there should be * no threads blocked waiting to send. */ dest_port = reply_port; local_seqno = rcv_mqueue->imq_seqno++; imq_unlock(rcv_mqueue); splx(s); /* * inline ipc_object_release. * Port is still locked. * Reference count was not incremented. */ ip_check_unlock(reply_port); if (option & MACH_RCV_TRAILER_MASK) { trailer->msgh_seqno = local_seqno; trailer->msgh_trailer_size = REQUESTED_TRAILER_SIZE(option); } /* copy out the kernel reply */ HOT(c_mmot_fastkernelreply++); goto fast_copyout; } slow_send: /* * Nothing is locked. We have acquired kmsg, but * we still need to send it and receive a reply. */ mr = ipc_kmsg_send(kmsg, MACH_MSG_OPTION_NONE, MACH_MSG_TIMEOUT_NONE); if (mr != MACH_MSG_SUCCESS) { mr |= ipc_kmsg_copyout_pseudo(kmsg, space, current_map(), MACH_MSG_BODY_NULL); (void) ipc_kmsg_put(msg_addr, kmsg, kmsg->ikm_header->msgh_size); return(mr); } slow_get_rcv_port: /* * We have sent the message. Copy in the receive port. */ mr = ipc_mqueue_copyin(space, rcv_name, &rcv_mqueue, &rcv_object); if (mr != MACH_MSG_SUCCESS) { return(mr); } /* hold ref for rcv_object */ /* * slow_receive: * * Now we have sent the request and copied in rcv_name, * and hold ref for rcv_object (to keep mqueue alive). * Just receive a reply and try to get back to fast path. */ self->ith_continuation = (void (*)(mach_msg_return_t))0; ipc_mqueue_receive(rcv_mqueue, MACH_MSG_OPTION_NONE, MACH_MSG_SIZE_MAX, MACH_MSG_TIMEOUT_NONE, THREAD_ABORTSAFE); mr = self->ith_state; temp_seqno = self->ith_seqno; ipc_object_release(rcv_object); if (mr != MACH_MSG_SUCCESS) { return(mr); } kmsg = self->ith_kmsg; hdr = kmsg->ikm_header; send_size = hdr->msgh_size; trailer = (mach_msg_format_0_trailer_t *) ((vm_offset_t) hdr + round_msg(send_size)); if (option & MACH_RCV_TRAILER_MASK) { trailer->msgh_seqno = temp_seqno; trailer->msgh_trailer_size = REQUESTED_TRAILER_SIZE(option); } dest_port = (ipc_port_t) hdr->msgh_remote_port; HOT(c_mmot_cold_055++); goto fast_copyout; slow_copyout: /* * Nothing locked and no references held, except * we have kmsg with msgh_seqno filled in. Must * still check against rcv_size and do * ipc_kmsg_copyout/ipc_kmsg_put. */ /* LP64support - have to compute real size as it would be received */ reply_size = ipc_kmsg_copyout_size(kmsg, current_map()) + REQUESTED_TRAILER_SIZE(option); if (rcv_size < reply_size) { if (msg_receive_error(kmsg, msg_addr, option, temp_seqno, space) == MACH_RCV_INVALID_DATA) { mr = MACH_RCV_INVALID_DATA; return(mr); } else { mr = MACH_RCV_TOO_LARGE; return(mr); } } mr = ipc_kmsg_copyout(kmsg, space, current_map(), MACH_PORT_NULL, MACH_MSG_BODY_NULL); if (mr != MACH_MSG_SUCCESS) { if ((mr &~ MACH_MSG_MASK) == MACH_RCV_BODY_ERROR) { if (ipc_kmsg_put(msg_addr, kmsg, reply_size) == MACH_RCV_INVALID_DATA) mr = MACH_RCV_INVALID_DATA; } else { if (msg_receive_error(kmsg, msg_addr, option, temp_seqno, space) == MACH_RCV_INVALID_DATA) mr = MACH_RCV_INVALID_DATA; } return(mr); } /* try to get back on optimized path */ HOT(c_mmot_getback_fast_put++); goto fast_put; /*NOTREACHED*/ } } /* END OF HOT PATH */ #endif /* ENABLE_HOTPATH */ if (option & MACH_SEND_MSG) { ipc_space_t space = current_space(); vm_map_t map = current_map(); ipc_kmsg_t kmsg; mr = ipc_kmsg_get(msg_addr, send_size, &kmsg); if (mr != MACH_MSG_SUCCESS) return mr; if (option & MACH_SEND_CANCEL) { if (notify == MACH_PORT_NULL) mr = MACH_SEND_INVALID_NOTIFY; else mr = ipc_kmsg_copyin(kmsg, space, map, notify); } else mr = ipc_kmsg_copyin(kmsg, space, map, MACH_PORT_NULL); if (mr != MACH_MSG_SUCCESS) { ipc_kmsg_free(kmsg); return mr; } mr = ipc_kmsg_send(kmsg, option & MACH_SEND_TIMEOUT, msg_timeout); if (mr != MACH_MSG_SUCCESS) { mr |= ipc_kmsg_copyout_pseudo(kmsg, space, map, MACH_MSG_BODY_NULL); (void) ipc_kmsg_put(msg_addr, kmsg, kmsg->ikm_header->msgh_size); return mr; } } if (option & MACH_RCV_MSG) { thread_t self = current_thread(); ipc_space_t space = current_space(); ipc_object_t object; ipc_mqueue_t mqueue; mr = ipc_mqueue_copyin(space, rcv_name, &mqueue, &object); if (mr != MACH_MSG_SUCCESS) { return mr; } /* hold ref for object */ /* * 1. MACH_RCV_OVERWRITE is on, and rcv_msg is our scatter list * and receive buffer * 2. MACH_RCV_OVERWRITE is off, and rcv_msg might be the * alternate receive buffer (separate send and receive buffers). */ if (option & MACH_RCV_OVERWRITE) self->ith_msg_addr = rcv_msg_addr; else if (rcv_msg_addr != (mach_vm_address_t)0) self->ith_msg_addr = rcv_msg_addr; else self->ith_msg_addr = msg_addr; self->ith_object = object; self->ith_msize = rcv_size; self->ith_option = option; self->ith_scatter_list_size = scatter_list_size; self->ith_continuation = thread_syscall_return; ipc_mqueue_receive(mqueue, option, rcv_size, msg_timeout, THREAD_ABORTSAFE); if ((option & MACH_RCV_TIMEOUT) && msg_timeout == 0) thread_poll_yield(self); return mach_msg_receive_results(); } return MACH_MSG_SUCCESS; } /* * Routine: mach_msg_trap [mach trap] * Purpose: * Possibly send a message; possibly receive a message. * Conditions: * Nothing locked. * Returns: * All of mach_msg_send and mach_msg_receive error codes. */ mach_msg_return_t mach_msg_trap( struct mach_msg_overwrite_trap_args *args) { kern_return_t kr; args->rcv_msg = (mach_vm_address_t)0; kr = mach_msg_overwrite_trap(args); return kr; } /* * Routine: msg_receive_error [internal] * Purpose: * Builds a minimal header/trailer and copies it to * the user message buffer. Invoked when in the case of a * MACH_RCV_TOO_LARGE or MACH_RCV_BODY_ERROR error. * Conditions: * Nothing locked. * Returns: * MACH_MSG_SUCCESS minimal header/trailer copied * MACH_RCV_INVALID_DATA copyout to user buffer failed */ mach_msg_return_t msg_receive_error( ipc_kmsg_t kmsg, mach_vm_address_t msg_addr, mach_msg_option_t option, mach_port_seqno_t seqno, ipc_space_t space) { mach_msg_format_0_trailer_t *trailer; /* * Copy out the destination port in the message. * Destroy all other rights and memory in the message. */ ipc_kmsg_copyout_dest(kmsg, space); /* * Build a minimal message with the requested trailer. */ trailer = (mach_msg_format_0_trailer_t *) ((vm_offset_t)kmsg->ikm_header + round_msg(sizeof(mach_msg_header_t))); kmsg->ikm_header->msgh_size = sizeof(mach_msg_header_t); bcopy( (char *)&trailer_template, (char *)trailer, sizeof(trailer_template)); if (option & MACH_RCV_TRAILER_MASK) { trailer->msgh_seqno = seqno; trailer->msgh_trailer_size = REQUESTED_TRAILER_SIZE(option); } /* * Copy the message to user space */ if (ipc_kmsg_put(msg_addr, kmsg, kmsg->ikm_header->msgh_size + trailer->msgh_trailer_size) == MACH_RCV_INVALID_DATA) return(MACH_RCV_INVALID_DATA); else return(MACH_MSG_SUCCESS); }