[IA64] move XP and XPC to drivers/misc/sgi-xp

Move XPC and XPNET from arch/ia64/sn/kernel to drivers/misc/sgi-xp.

Signed-off-by: Dean Nelson <dcn@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

1 files changed, 0 insertions, 2379 deletions

diff --git a/arch/ia64/sn/kernel/xpc_channel.c b/arch/ia64/sn/kernel/xpc_channel.c
deleted file mode 100644
index 44ccc0d789c9..000000000000
--- a/arch/ia64/sn/kernel/xpc_channel.c
+++ /dev/null
@@ -1,2379 +0,0 @@
-/*
- * This file is subject to the terms and conditions of the GNU General Public
- * License.  See the file "COPYING" in the main directory of this archive
- * for more details.
- *
- * Copyright (c) 2004-2006 Silicon Graphics, Inc.  All Rights Reserved.
- */
-
-
-/*
- * Cross Partition Communication (XPC) channel support.
- *
- *	This is the part of XPC that manages the channels and
- *	sends/receives messages across them to/from other partitions.
- *
- */
-
-
-#include <linux/kernel.h>
-#include <linux/init.h>
-#include <linux/sched.h>
-#include <linux/cache.h>
-#include <linux/interrupt.h>
-#include <linux/mutex.h>
-#include <linux/completion.h>
-#include <asm/sn/bte.h>
-#include <asm/sn/sn_sal.h>
-#include <asm/sn/xpc.h>
-
-
-/*
- * Guarantee that the kzalloc'd memory is cacheline aligned.
- */
-static void *
-xpc_kzalloc_cacheline_aligned(size_t size, gfp_t flags, void **base)
-{
-	/* see if kzalloc will give us cachline aligned memory by default */
-	*base = kzalloc(size, flags);
-	if (*base == NULL) {
-		return NULL;
-	}
-	if ((u64) *base == L1_CACHE_ALIGN((u64) *base)) {
-		return *base;
-	}
-	kfree(*base);
-
-	/* nope, we'll have to do it ourselves */
-	*base = kzalloc(size + L1_CACHE_BYTES, flags);
-	if (*base == NULL) {
-		return NULL;
-	}
-	return (void *) L1_CACHE_ALIGN((u64) *base);
-}
-
-
-/*
- * Set up the initial values for the XPartition Communication channels.
- */
-static void
-xpc_initialize_channels(struct xpc_partition *part, partid_t partid)
-{
-	int ch_number;
-	struct xpc_channel *ch;
-
-
-	for (ch_number = 0; ch_number < part->nchannels; ch_number++) {
-		ch = &part->channels[ch_number];
-
-		ch->partid = partid;
-		ch->number = ch_number;
-		ch->flags = XPC_C_DISCONNECTED;
-
-		ch->local_GP = &part->local_GPs[ch_number];
-		ch->local_openclose_args =
-					&part->local_openclose_args[ch_number];
-
-		atomic_set(&ch->kthreads_assigned, 0);
-		atomic_set(&ch->kthreads_idle, 0);
-		atomic_set(&ch->kthreads_active, 0);
-
-		atomic_set(&ch->references, 0);
-		atomic_set(&ch->n_to_notify, 0);
-
-		spin_lock_init(&ch->lock);
-		mutex_init(&ch->msg_to_pull_mutex);
-		init_completion(&ch->wdisconnect_wait);
-
-		atomic_set(&ch->n_on_msg_allocate_wq, 0);
-		init_waitqueue_head(&ch->msg_allocate_wq);
-		init_waitqueue_head(&ch->idle_wq);
-	}
-}
-
-
-/*
- * Setup the infrastructure necessary to support XPartition Communication
- * between the specified remote partition and the local one.
- */
-enum xpc_retval
-xpc_setup_infrastructure(struct xpc_partition *part)
-{
-	int ret, cpuid;
-	struct timer_list *timer;
-	partid_t partid = XPC_PARTID(part);
-
-
-	/*
-	 * Zero out MOST of the entry for this partition. Only the fields
-	 * starting with `nchannels' will be zeroed. The preceding fields must
-	 * remain `viable' across partition ups and downs, since they may be
-	 * referenced during this memset() operation.
-	 */
-	memset(&part->nchannels, 0, sizeof(struct xpc_partition) -
-				offsetof(struct xpc_partition, nchannels));
-
-	/*
-	 * Allocate all of the channel structures as a contiguous chunk of
-	 * memory.
-	 */
-	part->channels = kzalloc(sizeof(struct xpc_channel) * XPC_NCHANNELS,
-								GFP_KERNEL);
-	if (part->channels == NULL) {
-		dev_err(xpc_chan, "can't get memory for channels\n");
-		return xpcNoMemory;
-	}
-
-	part->nchannels = XPC_NCHANNELS;
-
-
-	/* allocate all the required GET/PUT values */
-
-	part->local_GPs = xpc_kzalloc_cacheline_aligned(XPC_GP_SIZE,
-					GFP_KERNEL, &part->local_GPs_base);
-	if (part->local_GPs == NULL) {
-		kfree(part->channels);
-		part->channels = NULL;
-		dev_err(xpc_chan, "can't get memory for local get/put "
-			"values\n");
-		return xpcNoMemory;
-	}
-
-	part->remote_GPs = xpc_kzalloc_cacheline_aligned(XPC_GP_SIZE,
-					GFP_KERNEL, &part->remote_GPs_base);
-	if (part->remote_GPs == NULL) {
-		dev_err(xpc_chan, "can't get memory for remote get/put "
-			"values\n");
-		kfree(part->local_GPs_base);
-		part->local_GPs = NULL;
-		kfree(part->channels);
-		part->channels = NULL;
-		return xpcNoMemory;
-	}
-
-
-	/* allocate all the required open and close args */
-
-	part->local_openclose_args = xpc_kzalloc_cacheline_aligned(
-					XPC_OPENCLOSE_ARGS_SIZE, GFP_KERNEL,
-					&part->local_openclose_args_base);
-	if (part->local_openclose_args == NULL) {
-		dev_err(xpc_chan, "can't get memory for local connect args\n");
-		kfree(part->remote_GPs_base);
-		part->remote_GPs = NULL;
-		kfree(part->local_GPs_base);
-		part->local_GPs = NULL;
-		kfree(part->channels);
-		part->channels = NULL;
-		return xpcNoMemory;
-	}
-
-	part->remote_openclose_args = xpc_kzalloc_cacheline_aligned(
-					XPC_OPENCLOSE_ARGS_SIZE, GFP_KERNEL,
-					&part->remote_openclose_args_base);
-	if (part->remote_openclose_args == NULL) {
-		dev_err(xpc_chan, "can't get memory for remote connect args\n");
-		kfree(part->local_openclose_args_base);
-		part->local_openclose_args = NULL;
-		kfree(part->remote_GPs_base);
-		part->remote_GPs = NULL;
-		kfree(part->local_GPs_base);
-		part->local_GPs = NULL;
-		kfree(part->channels);
-		part->channels = NULL;
-		return xpcNoMemory;
-	}
-
-
-	xpc_initialize_channels(part, partid);
-
-	atomic_set(&part->nchannels_active, 0);
-	atomic_set(&part->nchannels_engaged, 0);
-
-
-	/* local_IPI_amo were set to 0 by an earlier memset() */
-
-	/* Initialize this partitions AMO_t structure */
-	part->local_IPI_amo_va = xpc_IPI_init(partid);
-
-	spin_lock_init(&part->IPI_lock);
-
-	atomic_set(&part->channel_mgr_requests, 1);
-	init_waitqueue_head(&part->channel_mgr_wq);
-
-	sprintf(part->IPI_owner, "xpc%02d", partid);
-	ret = request_irq(SGI_XPC_NOTIFY, xpc_notify_IRQ_handler, IRQF_SHARED,
-				part->IPI_owner, (void *) (u64) partid);
-	if (ret != 0) {
-		dev_err(xpc_chan, "can't register NOTIFY IRQ handler, "
-			"errno=%d\n", -ret);
-		kfree(part->remote_openclose_args_base);
-		part->remote_openclose_args = NULL;
-		kfree(part->local_openclose_args_base);
-		part->local_openclose_args = NULL;
-		kfree(part->remote_GPs_base);
-		part->remote_GPs = NULL;
-		kfree(part->local_GPs_base);
-		part->local_GPs = NULL;
-		kfree(part->channels);
-		part->channels = NULL;
-		return xpcLackOfResources;
-	}
-
-	/* Setup a timer to check for dropped IPIs */
-	timer = &part->dropped_IPI_timer;
-	init_timer(timer);
-	timer->function = (void (*)(unsigned long)) xpc_dropped_IPI_check;
-	timer->data = (unsigned long) part;
-	timer->expires = jiffies + XPC_P_DROPPED_IPI_WAIT;
-	add_timer(timer);
-
-	/*
-	 * With the setting of the partition setup_state to XPC_P_SETUP, we're
-	 * declaring that this partition is ready to go.
-	 */
-	part->setup_state = XPC_P_SETUP;
-
-
-	/*
-	 * Setup the per partition specific variables required by the
-	 * remote partition to establish channel connections with us.
-	 *
-	 * The setting of the magic # indicates that these per partition
-	 * specific variables are ready to be used.
-	 */
-	xpc_vars_part[partid].GPs_pa = __pa(part->local_GPs);
-	xpc_vars_part[partid].openclose_args_pa =
-					__pa(part->local_openclose_args);
-	xpc_vars_part[partid].IPI_amo_pa = __pa(part->local_IPI_amo_va);
-	cpuid = raw_smp_processor_id();	/* any CPU in this partition will do */
-	xpc_vars_part[partid].IPI_nasid = cpuid_to_nasid(cpuid);
-	xpc_vars_part[partid].IPI_phys_cpuid = cpu_physical_id(cpuid);
-	xpc_vars_part[partid].nchannels = part->nchannels;
-	xpc_vars_part[partid].magic = XPC_VP_MAGIC1;
-
-	return xpcSuccess;
-}
-
-
-/*
- * Create a wrapper that hides the underlying mechanism for pulling a cacheline
- * (or multiple cachelines) from a remote partition.
- *
- * src must be a cacheline aligned physical address on the remote partition.
- * dst must be a cacheline aligned virtual address on this partition.
- * cnt must be an cacheline sized
- */
-static enum xpc_retval
-xpc_pull_remote_cachelines(struct xpc_partition *part, void *dst,
-				const void *src, size_t cnt)
-{
-	bte_result_t bte_ret;
-
-
-	DBUG_ON((u64) src != L1_CACHE_ALIGN((u64) src));
-	DBUG_ON((u64) dst != L1_CACHE_ALIGN((u64) dst));
-	DBUG_ON(cnt != L1_CACHE_ALIGN(cnt));
-
-	if (part->act_state == XPC_P_DEACTIVATING) {
-		return part->reason;
-	}
-
-	bte_ret = xp_bte_copy((u64) src, (u64) dst, (u64) cnt,
-					(BTE_NORMAL | BTE_WACQUIRE), NULL);
-	if (bte_ret == BTE_SUCCESS) {
-		return xpcSuccess;
-	}
-
-	dev_dbg(xpc_chan, "xp_bte_copy() from partition %d failed, ret=%d\n",
-		XPC_PARTID(part), bte_ret);
-
-	return xpc_map_bte_errors(bte_ret);
-}
-
-
-/*
- * Pull the remote per partition specific variables from the specified
- * partition.
- */
-enum xpc_retval
-xpc_pull_remote_vars_part(struct xpc_partition *part)
-{
-	u8 buffer[L1_CACHE_BYTES * 2];
-	struct xpc_vars_part *pulled_entry_cacheline =
-			(struct xpc_vars_part *) L1_CACHE_ALIGN((u64) buffer);
-	struct xpc_vars_part *pulled_entry;
-	u64 remote_entry_cacheline_pa, remote_entry_pa;
-	partid_t partid = XPC_PARTID(part);
-	enum xpc_retval ret;
-
-
-	/* pull the cacheline that contains the variables we're interested in */
-
-	DBUG_ON(part->remote_vars_part_pa !=
-				L1_CACHE_ALIGN(part->remote_vars_part_pa));
-	DBUG_ON(sizeof(struct xpc_vars_part) != L1_CACHE_BYTES / 2);
-
-	remote_entry_pa = part->remote_vars_part_pa +
-			sn_partition_id * sizeof(struct xpc_vars_part);
-
-	remote_entry_cacheline_pa = (remote_entry_pa & ~(L1_CACHE_BYTES - 1));
-
-	pulled_entry = (struct xpc_vars_part *) ((u64) pulled_entry_cacheline +
-				(remote_entry_pa & (L1_CACHE_BYTES - 1)));
-
-	ret = xpc_pull_remote_cachelines(part, pulled_entry_cacheline,
-					(void *) remote_entry_cacheline_pa,
-					L1_CACHE_BYTES);
-	if (ret != xpcSuccess) {
-		dev_dbg(xpc_chan, "failed to pull XPC vars_part from "
-			"partition %d, ret=%d\n", partid, ret);
-		return ret;
-	}
-
-
-	/* see if they've been set up yet */
-
-	if (pulled_entry->magic != XPC_VP_MAGIC1 &&
-				pulled_entry->magic != XPC_VP_MAGIC2) {
-
-		if (pulled_entry->magic != 0) {
-			dev_dbg(xpc_chan, "partition %d's XPC vars_part for "
-				"partition %d has bad magic value (=0x%lx)\n",
-				partid, sn_partition_id, pulled_entry->magic);
-			return xpcBadMagic;
-		}
-
-		/* they've not been initialized yet */
-		return xpcRetry;
-	}
-
-	if (xpc_vars_part[partid].magic == XPC_VP_MAGIC1) {
-
-		/* validate the variables */
-
-		if (pulled_entry->GPs_pa == 0 ||
-				pulled_entry->openclose_args_pa == 0 ||
-					pulled_entry->IPI_amo_pa == 0) {
-
-			dev_err(xpc_chan, "partition %d's XPC vars_part for "
-				"partition %d are not valid\n", partid,
-				sn_partition_id);
-			return xpcInvalidAddress;
-		}
-
-		/* the variables we imported look to be valid */
-
-		part->remote_GPs_pa = pulled_entry->GPs_pa;
-		part->remote_openclose_args_pa =
-					pulled_entry->openclose_args_pa;
-		part->remote_IPI_amo_va =
-				      (AMO_t *) __va(pulled_entry->IPI_amo_pa);
-		part->remote_IPI_nasid = pulled_entry->IPI_nasid;
-		part->remote_IPI_phys_cpuid = pulled_entry->IPI_phys_cpuid;
-
-		if (part->nchannels > pulled_entry->nchannels) {
-			part->nchannels = pulled_entry->nchannels;
-		}
-
-		/* let the other side know that we've pulled their variables */
-
-		xpc_vars_part[partid].magic = XPC_VP_MAGIC2;
-	}
-
-	if (pulled_entry->magic == XPC_VP_MAGIC1) {
-		return xpcRetry;
-	}
-
-	return xpcSuccess;
-}
-
-
-/*
- * Get the IPI flags and pull the openclose args and/or remote GPs as needed.
- */
-static u64
-xpc_get_IPI_flags(struct xpc_partition *part)
-{
-	unsigned long irq_flags;
-	u64 IPI_amo;
-	enum xpc_retval ret;
-
-
-	/*
-	 * See if there are any IPI flags to be handled.
-	 */
-
-	spin_lock_irqsave(&part->IPI_lock, irq_flags);
-	if ((IPI_amo = part->local_IPI_amo) != 0) {
-		part->local_IPI_amo = 0;
-	}
-	spin_unlock_irqrestore(&part->IPI_lock, irq_flags);
-
-
-	if (XPC_ANY_OPENCLOSE_IPI_FLAGS_SET(IPI_amo)) {
-		ret = xpc_pull_remote_cachelines(part,
-					part->remote_openclose_args,
-					(void *) part->remote_openclose_args_pa,
-					XPC_OPENCLOSE_ARGS_SIZE);
-		if (ret != xpcSuccess) {
-			XPC_DEACTIVATE_PARTITION(part, ret);
-
-			dev_dbg(xpc_chan, "failed to pull openclose args from "
-				"partition %d, ret=%d\n", XPC_PARTID(part),
-				ret);
-
-			/* don't bother processing IPIs anymore */
-			IPI_amo = 0;
-		}
-	}
-
-	if (XPC_ANY_MSG_IPI_FLAGS_SET(IPI_amo)) {
-		ret = xpc_pull_remote_cachelines(part, part->remote_GPs,
-						(void *) part->remote_GPs_pa,
-						XPC_GP_SIZE);
-		if (ret != xpcSuccess) {
-			XPC_DEACTIVATE_PARTITION(part, ret);
-
-			dev_dbg(xpc_chan, "failed to pull GPs from partition "
-				"%d, ret=%d\n", XPC_PARTID(part), ret);
-
-			/* don't bother processing IPIs anymore */
-			IPI_amo = 0;
-		}
-	}
-
-	return IPI_amo;
-}
-
-
-/*
- * Allocate the local message queue and the notify queue.
- */
-static enum xpc_retval
-xpc_allocate_local_msgqueue(struct xpc_channel *ch)
-{
-	unsigned long irq_flags;
-	int nentries;
-	size_t nbytes;
-
-
-	// >>> may want to check for ch->flags & XPC_C_DISCONNECTING between
-	// >>> iterations of the for-loop, bail if set?
-
-	// >>> should we impose a minimum #of entries? like 4 or 8?
-	for (nentries = ch->local_nentries; nentries > 0; nentries--) {
-
-		nbytes = nentries * ch->msg_size;
-		ch->local_msgqueue = xpc_kzalloc_cacheline_aligned(nbytes,
-						GFP_KERNEL,
-						&ch->local_msgqueue_base);
-		if (ch->local_msgqueue == NULL) {
-			continue;
-		}
-
-		nbytes = nentries * sizeof(struct xpc_notify);
-		ch->notify_queue = kzalloc(nbytes, GFP_KERNEL);
-		if (ch->notify_queue == NULL) {
-			kfree(ch->local_msgqueue_base);
-			ch->local_msgqueue = NULL;
-			continue;
-		}
-
-		spin_lock_irqsave(&ch->lock, irq_flags);
-		if (nentries < ch->local_nentries) {
-			dev_dbg(xpc_chan, "nentries=%d local_nentries=%d, "
-				"partid=%d, channel=%d\n", nentries,
-				ch->local_nentries, ch->partid, ch->number);
-
-			ch->local_nentries = nentries;
-		}
-		spin_unlock_irqrestore(&ch->lock, irq_flags);
-		return xpcSuccess;
-	}
-
-	dev_dbg(xpc_chan, "can't get memory for local message queue and notify "
-		"queue, partid=%d, channel=%d\n", ch->partid, ch->number);
-	return xpcNoMemory;
-}
-
-
-/*
- * Allocate the cached remote message queue.
- */
-static enum xpc_retval
-xpc_allocate_remote_msgqueue(struct xpc_channel *ch)
-{
-	unsigned long irq_flags;
-	int nentries;
-	size_t nbytes;
-
-
-	DBUG_ON(ch->remote_nentries <= 0);
-
-	// >>> may want to check for ch->flags & XPC_C_DISCONNECTING between
-	// >>> iterations of the for-loop, bail if set?
-
-	// >>> should we impose a minimum #of entries? like 4 or 8?
-	for (nentries = ch->remote_nentries; nentries > 0; nentries--) {
-
-		nbytes = nentries * ch->msg_size;
-		ch->remote_msgqueue = xpc_kzalloc_cacheline_aligned(nbytes,
-						GFP_KERNEL,
-						&ch->remote_msgqueue_base);
-		if (ch->remote_msgqueue == NULL) {
-			continue;
-		}
-
-		spin_lock_irqsave(&ch->lock, irq_flags);
-		if (nentries < ch->remote_nentries) {
-			dev_dbg(xpc_chan, "nentries=%d remote_nentries=%d, "
-				"partid=%d, channel=%d\n", nentries,
-				ch->remote_nentries, ch->partid, ch->number);
-
-			ch->remote_nentries = nentries;
-		}
-		spin_unlock_irqrestore(&ch->lock, irq_flags);
-		return xpcSuccess;
-	}
-
-	dev_dbg(xpc_chan, "can't get memory for cached remote message queue, "
-		"partid=%d, channel=%d\n", ch->partid, ch->number);
-	return xpcNoMemory;
-}
-
-
-/*
- * Allocate message queues and other stuff associated with a channel.
- *
- * Note: Assumes all of the channel sizes are filled in.
- */
-static enum xpc_retval
-xpc_allocate_msgqueues(struct xpc_channel *ch)
-{
-	unsigned long irq_flags;
-	enum xpc_retval ret;
-
-
-	DBUG_ON(ch->flags & XPC_C_SETUP);
-
-	if ((ret = xpc_allocate_local_msgqueue(ch)) != xpcSuccess) {
-		return ret;
-	}
-
-	if ((ret = xpc_allocate_remote_msgqueue(ch)) != xpcSuccess) {
-		kfree(ch->local_msgqueue_base);
-		ch->local_msgqueue = NULL;
-		kfree(ch->notify_queue);
-		ch->notify_queue = NULL;
-		return ret;
-	}
-
-	spin_lock_irqsave(&ch->lock, irq_flags);
-	ch->flags |= XPC_C_SETUP;
-	spin_unlock_irqrestore(&ch->lock, irq_flags);
-
-	return xpcSuccess;
-}
-
-
-/*
- * Process a connect message from a remote partition.
- *
- * Note: xpc_process_connect() is expecting to be called with the
- * spin_lock_irqsave held and will leave it locked upon return.
- */
-static void
-xpc_process_connect(struct xpc_channel *ch, unsigned long *irq_flags)
-{
-	enum xpc_retval ret;
-
-
-	DBUG_ON(!spin_is_locked(&ch->lock));
-
-	if (!(ch->flags & XPC_C_OPENREQUEST) ||
-				!(ch->flags & XPC_C_ROPENREQUEST)) {
-		/* nothing more to do for now */
-		return;
-	}
-	DBUG_ON(!(ch->flags & XPC_C_CONNECTING));
-
-	if (!(ch->flags & XPC_C_SETUP)) {
-		spin_unlock_irqrestore(&ch->lock, *irq_flags);
-		ret = xpc_allocate_msgqueues(ch);
-		spin_lock_irqsave(&ch->lock, *irq_flags);
-
-		if (ret != xpcSuccess) {
-			XPC_DISCONNECT_CHANNEL(ch, ret, irq_flags);
-		}
-		if (ch->flags & (XPC_C_CONNECTED | XPC_C_DISCONNECTING)) {
-			return;
-		}
-
-		DBUG_ON(!(ch->flags & XPC_C_SETUP));
-		DBUG_ON(ch->local_msgqueue == NULL);
-		DBUG_ON(ch->remote_msgqueue == NULL);
-	}
-
-	if (!(ch->flags & XPC_C_OPENREPLY)) {
-		ch->flags |= XPC_C_OPENREPLY;
-		xpc_IPI_send_openreply(ch, irq_flags);
-	}
-
-	if (!(ch->flags & XPC_C_ROPENREPLY)) {
-		return;
-	}
-
-	DBUG_ON(ch->remote_msgqueue_pa == 0);
-
-	ch->flags = (XPC_C_CONNECTED | XPC_C_SETUP);	/* clear all else */
-
-	dev_info(xpc_chan, "channel %d to partition %d connected\n",
-		ch->number, ch->partid);
-
-	spin_unlock_irqrestore(&ch->lock, *irq_flags);
-	xpc_create_kthreads(ch, 1, 0);
-	spin_lock_irqsave(&ch->lock, *irq_flags);
-}
-
-
-/*
- * Notify those who wanted to be notified upon delivery of their message.
- */
-static void
-xpc_notify_senders(struct xpc_channel *ch, enum xpc_retval reason, s64 put)
-{
-	struct xpc_notify *notify;
-	u8 notify_type;
-	s64 get = ch->w_remote_GP.get - 1;
-
-
-	while (++get < put && atomic_read(&ch->n_to_notify) > 0) {
-
-		notify = &ch->notify_queue[get % ch->local_nentries];
-
-		/*
-		 * See if the notify entry indicates it was associated with
-		 * a message who's sender wants to be notified. It is possible
-		 * that it is, but someone else is doing or has done the
-		 * notification.
-		 */
-		notify_type = notify->type;
-		if (notify_type == 0 ||
-				cmpxchg(&notify->type, notify_type, 0) !=
-								notify_type) {
-			continue;
-		}
-
-		DBUG_ON(notify_type != XPC_N_CALL);
-
-		atomic_dec(&ch->n_to_notify);
-
-		if (notify->func != NULL) {
-			dev_dbg(xpc_chan, "notify->func() called, notify=0x%p, "
-				"msg_number=%ld, partid=%d, channel=%d\n",
-				(void *) notify, get, ch->partid, ch->number);
-
-			notify->func(reason, ch->partid, ch->number,
-								notify->key);
-
-			dev_dbg(xpc_chan, "notify->func() returned, "
-				"notify=0x%p, msg_number=%ld, partid=%d, "
-				"channel=%d\n", (void *) notify, get,
-				ch->partid, ch->number);
-		}
-	}
-}
-
-
-/*
- * Free up message queues and other stuff that were allocated for the specified
- * channel.
- *
- * Note: ch->reason and ch->reason_line are left set for debugging purposes,
- * they're cleared when XPC_C_DISCONNECTED is cleared.
- */
-static void
-xpc_free_msgqueues(struct xpc_channel *ch)
-{
-	DBUG_ON(!spin_is_locked(&ch->lock));
-	DBUG_ON(atomic_read(&ch->n_to_notify) != 0);
-
-	ch->remote_msgqueue_pa = 0;
-	ch->func = NULL;
-	ch->key = NULL;
-	ch->msg_size = 0;
-	ch->local_nentries = 0;
-	ch->remote_nentries = 0;
-	ch->kthreads_assigned_limit = 0;
-	ch->kthreads_idle_limit = 0;
-
-	ch->local_GP->get = 0;
-	ch->local_GP->put = 0;
-	ch->remote_GP.get = 0;
-	ch->remote_GP.put = 0;
-	ch->w_local_GP.get = 0;
-	ch->w_local_GP.put = 0;
-	ch->w_remote_GP.get = 0;
-	ch->w_remote_GP.put = 0;
-	ch->next_msg_to_pull = 0;
-
-	if (ch->flags & XPC_C_SETUP) {
-		ch->flags &= ~XPC_C_SETUP;
-
-		dev_dbg(xpc_chan, "ch->flags=0x%x, partid=%d, channel=%d\n",
-			ch->flags, ch->partid, ch->number);
-
-		kfree(ch->local_msgqueue_base);
-		ch->local_msgqueue = NULL;
-		kfree(ch->remote_msgqueue_base);
-		ch->remote_msgqueue = NULL;
-		kfree(ch->notify_queue);
-		ch->notify_queue = NULL;
-	}
-}
-
-
-/*
- * spin_lock_irqsave() is expected to be held on entry.
- */
-static void
-xpc_process_disconnect(struct xpc_channel *ch, unsigned long *irq_flags)
-{
-	struct xpc_partition *part = &xpc_partitions[ch->partid];
-	u32 channel_was_connected = (ch->flags & XPC_C_WASCONNECTED);
-
-
-	DBUG_ON(!spin_is_locked(&ch->lock));
-
-	if (!(ch->flags & XPC_C_DISCONNECTING)) {
-		return;
-	}
-
-	DBUG_ON(!(ch->flags & XPC_C_CLOSEREQUEST));
-
-	/* make sure all activity has settled down first */
-
-	if (atomic_read(&ch->kthreads_assigned) > 0 ||
-				atomic_read(&ch->references) > 0) {
-		return;
-	}
-	DBUG_ON((ch->flags & XPC_C_CONNECTEDCALLOUT_MADE) &&
-			!(ch->flags & XPC_C_DISCONNECTINGCALLOUT_MADE));
-
-	if (part->act_state == XPC_P_DEACTIVATING) {
-		/* can't proceed until the other side disengages from us */
-		if (xpc_partition_engaged(1UL << ch->partid)) {
-			return;
-		}
-
-	} else {
-
-		/* as long as the other side is up do the full protocol */
-
-		if (!(ch->flags & XPC_C_RCLOSEREQUEST)) {
-			return;
-		}
-
-		if (!(ch->flags & XPC_C_CLOSEREPLY)) {
-			ch->flags |= XPC_C_CLOSEREPLY;
-			xpc_IPI_send_closereply(ch, irq_flags);
-		}
-
-		if (!(ch->flags & XPC_C_RCLOSEREPLY)) {
-			return;
-		}
-	}
-
-	/* wake those waiting for notify completion */
-	if (atomic_read(&ch->n_to_notify) > 0) {
-		/* >>> we do callout while holding ch->lock */
-		xpc_notify_senders(ch, ch->reason, ch->w_local_GP.put);
-	}
-
-	/* both sides are disconnected now */
-
-	if (ch->flags & XPC_C_DISCONNECTINGCALLOUT_MADE) {
-		spin_unlock_irqrestore(&ch->lock, *irq_flags);
-		xpc_disconnect_callout(ch, xpcDisconnected);
-		spin_lock_irqsave(&ch->lock, *irq_flags);
-	}
-
-	/* it's now safe to free the channel's message queues */
-	xpc_free_msgqueues(ch);
-
-	/* mark disconnected, clear all other flags except XPC_C_WDISCONNECT */
-	ch->flags = (XPC_C_DISCONNECTED | (ch->flags & XPC_C_WDISCONNECT));
-
-	atomic_dec(&part->nchannels_active);
-
-	if (channel_was_connected) {
-		dev_info(xpc_chan, "channel %d to partition %d disconnected, "
-			"reason=%d\n", ch->number, ch->partid, ch->reason);
-	}
-
-	if (ch->flags & XPC_C_WDISCONNECT) {
-		/* we won't lose the CPU since we're holding ch->lock */
-		complete(&ch->wdisconnect_wait);
-	} else if (ch->delayed_IPI_flags) {
-		if (part->act_state != XPC_P_DEACTIVATING) {
-			/* time to take action on any delayed IPI flags */
-			spin_lock(&part->IPI_lock);
-			XPC_SET_IPI_FLAGS(part->local_IPI_amo, ch->number,
-							ch->delayed_IPI_flags);
-			spin_unlock(&part->IPI_lock);
-		}
-		ch->delayed_IPI_flags = 0;
-	}
-}
-
-
-/*
- * Process a change in the channel's remote connection state.
- */
-static void
-xpc_process_openclose_IPI(struct xpc_partition *part, int ch_number,
-				u8 IPI_flags)
-{
-	unsigned long irq_flags;
-	struct xpc_openclose_args *args =
-				&part->remote_openclose_args[ch_number];
-	struct xpc_channel *ch = &part->channels[ch_number];
-	enum xpc_retval reason;
-
-
-
-	spin_lock_irqsave(&ch->lock, irq_flags);
-
-again:
-
-	if ((ch->flags & XPC_C_DISCONNECTED) &&
-					(ch->flags & XPC_C_WDISCONNECT)) {
-		/*
-		 * Delay processing IPI flags until thread waiting disconnect
-		 * has had a chance to see that the channel is disconnected.
-		 */
-		ch->delayed_IPI_flags |= IPI_flags;
-		spin_unlock_irqrestore(&ch->lock, irq_flags);
-		return;
-	}
-
-
-	if (IPI_flags & XPC_IPI_CLOSEREQUEST) {
-
-		dev_dbg(xpc_chan, "XPC_IPI_CLOSEREQUEST (reason=%d) received "
-			"from partid=%d, channel=%d\n", args->reason,
-			ch->partid, ch->number);
-
-		/*
-		 * If RCLOSEREQUEST is set, we're probably waiting for
-		 * RCLOSEREPLY. We should find it and a ROPENREQUEST packed
-		 * with this RCLOSEREQUEST in the IPI_flags.
-		 */
-
-		if (ch->flags & XPC_C_RCLOSEREQUEST) {
-			DBUG_ON(!(ch->flags & XPC_C_DISCONNECTING));
-			DBUG_ON(!(ch->flags & XPC_C_CLOSEREQUEST));
-			DBUG_ON(!(ch->flags & XPC_C_CLOSEREPLY));
-			DBUG_ON(ch->flags & XPC_C_RCLOSEREPLY);
-
-			DBUG_ON(!(IPI_flags & XPC_IPI_CLOSEREPLY));
-			IPI_flags &= ~XPC_IPI_CLOSEREPLY;
-			ch->flags |= XPC_C_RCLOSEREPLY;
-
-			/* both sides have finished disconnecting */
-			xpc_process_disconnect(ch, &irq_flags);
-			DBUG_ON(!(ch->flags & XPC_C_DISCONNECTED));
-			goto again;
-		}
-
-		if (ch->flags & XPC_C_DISCONNECTED) {
-			if (!(IPI_flags & XPC_IPI_OPENREQUEST)) {
-				if ((XPC_GET_IPI_FLAGS(part->local_IPI_amo,
-					 ch_number) & XPC_IPI_OPENREQUEST)) {
-
-					DBUG_ON(ch->delayed_IPI_flags != 0);
-					spin_lock(&part->IPI_lock);
-					XPC_SET_IPI_FLAGS(part->local_IPI_amo,
-							ch_number,
-							XPC_IPI_CLOSEREQUEST);
-					spin_unlock(&part->IPI_lock);
-				}
-				spin_unlock_irqrestore(&ch->lock, irq_flags);
-				return;
-			}
-
-			XPC_SET_REASON(ch, 0, 0);
-			ch->flags &= ~XPC_C_DISCONNECTED;
-
-			atomic_inc(&part->nchannels_active);
-			ch->flags |= (XPC_C_CONNECTING | XPC_C_ROPENREQUEST);
-		}
-
-		IPI_flags &= ~(XPC_IPI_OPENREQUEST | XPC_IPI_OPENREPLY);
-
-		/*
-		 * The meaningful CLOSEREQUEST connection state fields are:
-		 *      reason = reason connection is to be closed
-		 */
-
-		ch->flags |= XPC_C_RCLOSEREQUEST;
-
-		if (!(ch->flags & XPC_C_DISCONNECTING)) {
-			reason = args->reason;
-			if (reason <= xpcSuccess || reason > xpcUnknownReason) {
-				reason = xpcUnknownReason;
-			} else if (reason == xpcUnregistering) {
-				reason = xpcOtherUnregistering;
-			}
-
-			XPC_DISCONNECT_CHANNEL(ch, reason, &irq_flags);
-
-			DBUG_ON(IPI_flags & XPC_IPI_CLOSEREPLY);
-			spin_unlock_irqrestore(&ch->lock, irq_flags);
-			return;
-		}
-
-		xpc_process_disconnect(ch, &irq_flags);
-	}
-
-
-	if (IPI_flags & XPC_IPI_CLOSEREPLY) {
-
-		dev_dbg(xpc_chan, "XPC_IPI_CLOSEREPLY received from partid=%d,"
-			" channel=%d\n", ch->partid, ch->number);
-
-		if (ch->flags & XPC_C_DISCONNECTED) {
-			DBUG_ON(part->act_state != XPC_P_DEACTIVATING);
-			spin_unlock_irqrestore(&ch->lock, irq_flags);
-			return;
-		}
-
-		DBUG_ON(!(ch->flags & XPC_C_CLOSEREQUEST));
-
-		if (!(ch->flags & XPC_C_RCLOSEREQUEST)) {
-			if ((XPC_GET_IPI_FLAGS(part->local_IPI_amo, ch_number)
-						& XPC_IPI_CLOSEREQUEST)) {
-
-				DBUG_ON(ch->delayed_IPI_flags != 0);
-				spin_lock(&part->IPI_lock);
-				XPC_SET_IPI_FLAGS(part->local_IPI_amo,
-						ch_number, XPC_IPI_CLOSEREPLY);
-				spin_unlock(&part->IPI_lock);
-			}
-			spin_unlock_irqrestore(&ch->lock, irq_flags);
-			return;
-		}
-
-		ch->flags |= XPC_C_RCLOSEREPLY;
-
-		if (ch->flags & XPC_C_CLOSEREPLY) {
-			/* both sides have finished disconnecting */
-			xpc_process_disconnect(ch, &irq_flags);
-		}
-	}
-
-
-	if (IPI_flags & XPC_IPI_OPENREQUEST) {
-
-		dev_dbg(xpc_chan, "XPC_IPI_OPENREQUEST (msg_size=%d, "
-			"local_nentries=%d) received from partid=%d, "
-			"channel=%d\n", args->msg_size, args->local_nentries,
-			ch->partid, ch->number);
-
-		if (part->act_state == XPC_P_DEACTIVATING ||
-					(ch->flags & XPC_C_ROPENREQUEST)) {
-			spin_unlock_irqrestore(&ch->lock, irq_flags);
-			return;
-		}
-
-		if (ch->flags & (XPC_C_DISCONNECTING | XPC_C_WDISCONNECT)) {
-			ch->delayed_IPI_flags |= XPC_IPI_OPENREQUEST;
-			spin_unlock_irqrestore(&ch->lock, irq_flags);
-			return;
-		}
-		DBUG_ON(!(ch->flags & (XPC_C_DISCONNECTED |
-							XPC_C_OPENREQUEST)));
-		DBUG_ON(ch->flags & (XPC_C_ROPENREQUEST | XPC_C_ROPENREPLY |
-					XPC_C_OPENREPLY | XPC_C_CONNECTED));
-
-		/*
-		 * The meaningful OPENREQUEST connection state fields are:
-		 *      msg_size = size of channel's messages in bytes
-		 *      local_nentries = remote partition's local_nentries
-		 */
-		if (args->msg_size == 0 || args->local_nentries == 0) {
-			/* assume OPENREQUEST was delayed by mistake */
-			spin_unlock_irqrestore(&ch->lock, irq_flags);
-			return;
-		}
-
-		ch->flags |= (XPC_C_ROPENREQUEST | XPC_C_CONNECTING);
-		ch->remote_nentries = args->local_nentries;
-
-
-		if (ch->flags & XPC_C_OPENREQUEST) {
-			if (args->msg_size != ch->msg_size) {
-				XPC_DISCONNECT_CHANNEL(ch, xpcUnequalMsgSizes,
-								&irq_flags);
-				spin_unlock_irqrestore(&ch->lock, irq_flags);
-				return;
-			}
-		} else {
-			ch->msg_size = args->msg_size;
-
-			XPC_SET_REASON(ch, 0, 0);
-			ch->flags &= ~XPC_C_DISCONNECTED;
-
-			atomic_inc(&part->nchannels_active);
-		}
-
-		xpc_process_connect(ch, &irq_flags);
-	}
-
-
-	if (IPI_flags & XPC_IPI_OPENREPLY) {
-
-		dev_dbg(xpc_chan, "XPC_IPI_OPENREPLY (local_msgqueue_pa=0x%lx, "
-			"local_nentries=%d, remote_nentries=%d) received from "
-			"partid=%d, channel=%d\n", args->local_msgqueue_pa,
-			args->local_nentries, args->remote_nentries,
-			ch->partid, ch->number);
-
-		if (ch->flags & (XPC_C_DISCONNECTING | XPC_C_DISCONNECTED)) {
-			spin_unlock_irqrestore(&ch->lock, irq_flags);
-			return;
-		}
-		if (!(ch->flags & XPC_C_OPENREQUEST)) {
-			XPC_DISCONNECT_CHANNEL(ch, xpcOpenCloseError,
-								&irq_flags);
-			spin_unlock_irqrestore(&ch->lock, irq_flags);
-			return;
-		}
-
-		DBUG_ON(!(ch->flags & XPC_C_ROPENREQUEST));
-		DBUG_ON(ch->flags & XPC_C_CONNECTED);
-
-		/*
-		 * The meaningful OPENREPLY connection state fields are:
-		 *      local_msgqueue_pa = physical address of remote
-		 *			    partition's local_msgqueue
-		 *      local_nentries = remote partition's local_nentries
-		 *      remote_nentries = remote partition's remote_nentries
-		 */
-		DBUG_ON(args->local_msgqueue_pa == 0);
-		DBUG_ON(args->local_nentries == 0);
-		DBUG_ON(args->remote_nentries == 0);
-
-		ch->flags |= XPC_C_ROPENREPLY;
-		ch->remote_msgqueue_pa = args->local_msgqueue_pa;
-
-		if (args->local_nentries < ch->remote_nentries) {
-			dev_dbg(xpc_chan, "XPC_IPI_OPENREPLY: new "
-				"remote_nentries=%d, old remote_nentries=%d, "
-				"partid=%d, channel=%d\n",
-				args->local_nentries, ch->remote_nentries,
-				ch->partid, ch->number);
-
-			ch->remote_nentries = args->local_nentries;
-		}
-		if (args->remote_nentries < ch->local_nentries) {
-			dev_dbg(xpc_chan, "XPC_IPI_OPENREPLY: new "
-				"local_nentries=%d, old local_nentries=%d, "
-				"partid=%d, channel=%d\n",
-				args->remote_nentries, ch->local_nentries,
-				ch->partid, ch->number);
-
-			ch->local_nentries = args->remote_nentries;
-		}
-
-		xpc_process_connect(ch, &irq_flags);
-	}
-
-	spin_unlock_irqrestore(&ch->lock, irq_flags);
-}
-
-
-/*
- * Attempt to establish a channel connection to a remote partition.
- */
-static enum xpc_retval
-xpc_connect_channel(struct xpc_channel *ch)
-{
-	unsigned long irq_flags;
-	struct xpc_registration *registration = &xpc_registrations[ch->number];
-
-
-	if (mutex_trylock(&registration->mutex) == 0) {
-		return xpcRetry;
-	}
-
-	if (!XPC_CHANNEL_REGISTERED(ch->number)) {
-		mutex_unlock(&registration->mutex);
-		return xpcUnregistered;
-	}
-
-	spin_lock_irqsave(&ch->lock, irq_flags);
-
-	DBUG_ON(ch->flags & XPC_C_CONNECTED);
-	DBUG_ON(ch->flags & XPC_C_OPENREQUEST);
-
-	if (ch->flags & XPC_C_DISCONNECTING) {
-		spin_unlock_irqrestore(&ch->lock, irq_flags);
-		mutex_unlock(&registration->mutex);
-		return ch->reason;
-	}
-
-
-	/* add info from the channel connect registration to the channel */
-
-	ch->kthreads_assigned_limit = registration->assigned_limit;
-	ch->kthreads_idle_limit = registration->idle_limit;
-	DBUG_ON(atomic_read(&ch->kthreads_assigned) != 0);
-	DBUG_ON(atomic_read(&ch->kthreads_idle) != 0);
-	DBUG_ON(atomic_read(&ch->kthreads_active) != 0);
-
-	ch->func = registration->func;
-	DBUG_ON(registration->func == NULL);
-	ch->key = registration->key;
-
-	ch->local_nentries = registration->nentries;
-
-	if (ch->flags & XPC_C_ROPENREQUEST) {
-		if (registration->msg_size != ch->msg_size) {
-			/* the local and remote sides aren't the same */
-
-			/*
-			 * Because XPC_DISCONNECT_CHANNEL() can block we're
-			 * forced to up the registration sema before we unlock
-			 * the channel lock. But that's okay here because we're
-			 * done with the part that required the registration
-			 * sema. XPC_DISCONNECT_CHANNEL() requires that the
-			 * channel lock be locked and will unlock and relock
-			 * the channel lock as needed.
-			 */
-			mutex_unlock(&registration->mutex);
-			XPC_DISCONNECT_CHANNEL(ch, xpcUnequalMsgSizes,
-								&irq_flags);
-			spin_unlock_irqrestore(&ch->lock, irq_flags);
-			return xpcUnequalMsgSizes;
-		}
-	} else {
-		ch->msg_size = registration->msg_size;
-
-		XPC_SET_REASON(ch, 0, 0);
-		ch->flags &= ~XPC_C_DISCONNECTED;
-
-		atomic_inc(&xpc_partitions[ch->partid].nchannels_active);
-	}
-
-	mutex_unlock(&registration->mutex);
-
-
-	/* initiate the connection */
-
-	ch->flags |= (XPC_C_OPENREQUEST | XPC_C_CONNECTING);
-	xpc_IPI_send_openrequest(ch, &irq_flags);
-
-	xpc_process_connect(ch, &irq_flags);
-
-	spin_unlock_irqrestore(&ch->lock, irq_flags);
-
-	return xpcSuccess;
-}
-
-
-/*
- * Clear some of the msg flags in the local message queue.
- */
-static inline void
-xpc_clear_local_msgqueue_flags(struct xpc_channel *ch)
-{
-	struct xpc_msg *msg;
-	s64 get;
-
-
-	get = ch->w_remote_GP.get;
-	do {
-		msg = (struct xpc_msg *) ((u64) ch->local_msgqueue +
-				(get % ch->local_nentries) * ch->msg_size);
-		msg->flags = 0;
-	} while (++get < (volatile s64) ch->remote_GP.get);
-}
-
-
-/*
- * Clear some of the msg flags in the remote message queue.
- */
-static inline void
-xpc_clear_remote_msgqueue_flags(struct xpc_channel *ch)
-{
-	struct xpc_msg *msg;
-	s64 put;
-
-
-	put = ch->w_remote_GP.put;
-	do {
-		msg = (struct xpc_msg *) ((u64) ch->remote_msgqueue +
-				(put % ch->remote_nentries) * ch->msg_size);
-		msg->flags = 0;
-	} while (++put < (volatile s64) ch->remote_GP.put);
-}
-
-
-static void
-xpc_process_msg_IPI(struct xpc_partition *part, int ch_number)
-{
-	struct xpc_channel *ch = &part->channels[ch_number];
-	int nmsgs_sent;
-
-
-	ch->remote_GP = part->remote_GPs[ch_number];
-
-
-	/* See what, if anything, has changed for each connected channel */
-
-	xpc_msgqueue_ref(ch);
-
-	if (ch->w_remote_GP.get == ch->remote_GP.get &&
-				ch->w_remote_GP.put == ch->remote_GP.put) {
-		/* nothing changed since GPs were last pulled */
-		xpc_msgqueue_deref(ch);
-		return;
-	}
-
-	if (!(ch->flags & XPC_C_CONNECTED)){
-		xpc_msgqueue_deref(ch);
-		return;
-	}
-
-
-	/*
-	 * First check to see if messages recently sent by us have been
-	 * received by the other side. (The remote GET value will have
-	 * changed since we last looked at it.)
-	 */
-
-	if (ch->w_remote_GP.get != ch->remote_GP.get) {
-
-		/*
-		 * We need to notify any senders that want to be notified
-		 * that their sent messages have been received by their
-		 * intended recipients. We need to do this before updating
-		 * w_remote_GP.get so that we don't allocate the same message
-		 * queue entries prematurely (see xpc_allocate_msg()).
-		 */
-		if (atomic_read(&ch->n_to_notify) > 0) {
-			/*
-			 * Notify senders that messages sent have been
-			 * received and delivered by the other side.
-			 */
-			xpc_notify_senders(ch, xpcMsgDelivered,
-							ch->remote_GP.get);
-		}
-
-		/*
-		 * Clear msg->flags in previously sent messages, so that
-		 * they're ready for xpc_allocate_msg().
-		 */
-		xpc_clear_local_msgqueue_flags(ch);
-
-		ch->w_remote_GP.get = ch->remote_GP.get;
-
-		dev_dbg(xpc_chan, "w_remote_GP.get changed to %ld, partid=%d, "
-			"channel=%d\n", ch->w_remote_GP.get, ch->partid,
-			ch->number);
-
-		/*
-		 * If anyone was waiting for message queue entries to become
-		 * available, wake them up.
-		 */
-		if (atomic_read(&ch->n_on_msg_allocate_wq) > 0) {
-			wake_up(&ch->msg_allocate_wq);
-		}
-	}
-
-
-	/*
-	 * Now check for newly sent messages by the other side. (The remote
-	 * PUT value will have changed since we last looked at it.)
-	 */
-
-	if (ch->w_remote_GP.put != ch->remote_GP.put) {
-		/*
-		 * Clear msg->flags in previously received messages, so that
-		 * they're ready for xpc_get_deliverable_msg().
-		 */
-		xpc_clear_remote_msgqueue_flags(ch);
-
-		ch->w_remote_GP.put = ch->remote_GP.put;
-
-		dev_dbg(xpc_chan, "w_remote_GP.put changed to %ld, partid=%d, "
-			"channel=%d\n", ch->w_remote_GP.put, ch->partid,
-			ch->number);
-
-		nmsgs_sent = ch->w_remote_GP.put - ch->w_local_GP.get;
-		if (nmsgs_sent > 0) {
-			dev_dbg(xpc_chan, "msgs waiting to be copied and "
-				"delivered=%d, partid=%d, channel=%d\n",
-				nmsgs_sent, ch->partid, ch->number);
-
-			if (ch->flags & XPC_C_CONNECTEDCALLOUT_MADE) {
-				xpc_activate_kthreads(ch, nmsgs_sent);
-			}
-		}
-	}
-
-	xpc_msgqueue_deref(ch);
-}
-
-
-void
-xpc_process_channel_activity(struct xpc_partition *part)
-{
-	unsigned long irq_flags;
-	u64 IPI_amo, IPI_flags;
-	struct xpc_channel *ch;
-	int ch_number;
-	u32 ch_flags;
-
-
-	IPI_amo = xpc_get_IPI_flags(part);
-
-	/*
-	 * Initiate channel connections for registered channels.
-	 *
-	 * For each connected channel that has pending messages activate idle
-	 * kthreads and/or create new kthreads as needed.
-	 */
-
-	for (ch_number = 0; ch_number < part->nchannels; ch_number++) {
-		ch = &part->channels[ch_number];
-
-
-		/*
-		 * Process any open or close related IPI flags, and then deal
-		 * with connecting or disconnecting the channel as required.
-		 */
-
-		IPI_flags = XPC_GET_IPI_FLAGS(IPI_amo, ch_number);
-
-		if (XPC_ANY_OPENCLOSE_IPI_FLAGS_SET(IPI_flags)) {
-			xpc_process_openclose_IPI(part, ch_number, IPI_flags);
-		}
-
-		ch_flags = ch->flags;	/* need an atomic snapshot of flags */
-
-		if (ch_flags & XPC_C_DISCONNECTING) {
-			spin_lock_irqsave(&ch->lock, irq_flags);
-			xpc_process_disconnect(ch, &irq_flags);
-			spin_unlock_irqrestore(&ch->lock, irq_flags);
-			continue;
-		}
-
-		if (part->act_state == XPC_P_DEACTIVATING) {
-			continue;
-		}
-
-		if (!(ch_flags & XPC_C_CONNECTED)) {
-			if (!(ch_flags & XPC_C_OPENREQUEST)) {
-				DBUG_ON(ch_flags & XPC_C_SETUP);
-				(void) xpc_connect_channel(ch);
-			} else {
-				spin_lock_irqsave(&ch->lock, irq_flags);
-				xpc_process_connect(ch, &irq_flags);
-				spin_unlock_irqrestore(&ch->lock, irq_flags);
-			}
-			continue;
-		}
-
-
-		/*
-		 * Process any message related IPI flags, this may involve the
-		 * activation of kthreads to deliver any pending messages sent
-		 * from the other partition.
-		 */
-
-		if (XPC_ANY_MSG_IPI_FLAGS_SET(IPI_flags)) {
-			xpc_process_msg_IPI(part, ch_number);
-		}
-	}
-}
-
-
-/*
- * XPC's heartbeat code calls this function to inform XPC that a partition is
- * going down.  XPC responds by tearing down the XPartition Communication
- * infrastructure used for the just downed partition.
- *
- * XPC's heartbeat code will never call this function and xpc_partition_up()
- * at the same time. Nor will it ever make multiple calls to either function
- * at the same time.
- */
-void
-xpc_partition_going_down(struct xpc_partition *part, enum xpc_retval reason)
-{
-	unsigned long irq_flags;
-	int ch_number;
-	struct xpc_channel *ch;
-
-
-	dev_dbg(xpc_chan, "deactivating partition %d, reason=%d\n",
-		XPC_PARTID(part), reason);
-
-	if (!xpc_part_ref(part)) {
-		/* infrastructure for this partition isn't currently set up */
-		return;
-	}
-
-
-	/* disconnect channels associated with the partition going down */
-
-	for (ch_number = 0; ch_number < part->nchannels; ch_number++) {
-		ch = &part->channels[ch_number];
-
-		xpc_msgqueue_ref(ch);
-		spin_lock_irqsave(&ch->lock, irq_flags);
-
-		XPC_DISCONNECT_CHANNEL(ch, reason, &irq_flags);
-
-		spin_unlock_irqrestore(&ch->lock, irq_flags);
-		xpc_msgqueue_deref(ch);
-	}
-
-	xpc_wakeup_channel_mgr(part);
-
-	xpc_part_deref(part);
-}
-
-
-/*
- * Teardown the infrastructure necessary to support XPartition Communication
- * between the specified remote partition and the local one.
- */
-void
-xpc_teardown_infrastructure(struct xpc_partition *part)
-{
-	partid_t partid = XPC_PARTID(part);
-
-
-	/*
-	 * We start off by making this partition inaccessible to local
-	 * processes by marking it as no longer setup. Then we make it
-	 * inaccessible to remote processes by clearing the XPC per partition
-	 * specific variable's magic # (which indicates that these variables
-	 * are no longer valid) and by ignoring all XPC notify IPIs sent to
-	 * this partition.
-	 */
-
-	DBUG_ON(atomic_read(&part->nchannels_engaged) != 0);
-	DBUG_ON(atomic_read(&part->nchannels_active) != 0);
-	DBUG_ON(part->setup_state != XPC_P_SETUP);
-	part->setup_state = XPC_P_WTEARDOWN;
-
-	xpc_vars_part[partid].magic = 0;
-
-
-	free_irq(SGI_XPC_NOTIFY, (void *) (u64) partid);
-
-
-	/*
-	 * Before proceeding with the teardown we have to wait until all
-	 * existing references cease.
-	 */
-	wait_event(part->teardown_wq, (atomic_read(&part->references) == 0));
-
-
-	/* now we can begin tearing down the infrastructure */
-
-	part->setup_state = XPC_P_TORNDOWN;
-
-	/* in case we've still got outstanding timers registered... */
-	del_timer_sync(&part->dropped_IPI_timer);
-
-	kfree(part->remote_openclose_args_base);
-	part->remote_openclose_args = NULL;
-	kfree(part->local_openclose_args_base);
-	part->local_openclose_args = NULL;
-	kfree(part->remote_GPs_base);
-	part->remote_GPs = NULL;
-	kfree(part->local_GPs_base);
-	part->local_GPs = NULL;
-	kfree(part->channels);
-	part->channels = NULL;
-	part->local_IPI_amo_va = NULL;
-}
-
-
-/*
- * Called by XP at the time of channel connection registration to cause
- * XPC to establish connections to all currently active partitions.
- */
-void
-xpc_initiate_connect(int ch_number)
-{
-	partid_t partid;
-	struct xpc_partition *part;
-	struct xpc_channel *ch;
-
-
-	DBUG_ON(ch_number < 0 || ch_number >= XPC_NCHANNELS);
-
-	for (partid = 1; partid < XP_MAX_PARTITIONS; partid++) {
-		part = &xpc_partitions[partid];
-
-		if (xpc_part_ref(part)) {
-			ch = &part->channels[ch_number];
-
-			/*
-			 * Initiate the establishment of a connection on the
-			 * newly registered channel to the remote partition.
-			 */
-			xpc_wakeup_channel_mgr(part);
-			xpc_part_deref(part);
-		}
-	}
-}
-
-
-void
-xpc_connected_callout(struct xpc_channel *ch)
-{
-	/* let the registerer know that a connection has been established */
-
-	if (ch->func != NULL) {
-		dev_dbg(xpc_chan, "ch->func() called, reason=xpcConnected, "
-			"partid=%d, channel=%d\n", ch->partid, ch->number);
-
-		ch->func(xpcConnected, ch->partid, ch->number,
-				(void *) (u64) ch->local_nentries, ch->key);
-
-		dev_dbg(xpc_chan, "ch->func() returned, reason=xpcConnected, "
-			"partid=%d, channel=%d\n", ch->partid, ch->number);
-	}
-}
-
-
-/*
- * Called by XP at the time of channel connection unregistration to cause
- * XPC to teardown all current connections for the specified channel.
- *
- * Before returning xpc_initiate_disconnect() will wait until all connections
- * on the specified channel have been closed/torndown. So the caller can be
- * assured that they will not be receiving any more callouts from XPC to the
- * function they registered via xpc_connect().
- *
- * Arguments:
- *
- *	ch_number - channel # to unregister.
- */
-void
-xpc_initiate_disconnect(int ch_number)
-{
-	unsigned long irq_flags;
-	partid_t partid;
-	struct xpc_partition *part;
-	struct xpc_channel *ch;
-
-
-	DBUG_ON(ch_number < 0 || ch_number >= XPC_NCHANNELS);
-
-	/* initiate the channel disconnect for every active partition */
-	for (partid = 1; partid < XP_MAX_PARTITIONS; partid++) {
-		part = &xpc_partitions[partid];
-
-		if (xpc_part_ref(part)) {
-			ch = &part->channels[ch_number];
-			xpc_msgqueue_ref(ch);
-
-			spin_lock_irqsave(&ch->lock, irq_flags);
-
-			if (!(ch->flags & XPC_C_DISCONNECTED)) {
-				ch->flags |= XPC_C_WDISCONNECT;
-
-				XPC_DISCONNECT_CHANNEL(ch, xpcUnregistering,
-								&irq_flags);
-			}
-
-			spin_unlock_irqrestore(&ch->lock, irq_flags);
-
-			xpc_msgqueue_deref(ch);
-			xpc_part_deref(part);
-		}
-	}
-
-	xpc_disconnect_wait(ch_number);
-}
-
-
-/*
- * To disconnect a channel, and reflect it back to all who may be waiting.
- *
- * An OPEN is not allowed until XPC_C_DISCONNECTING is cleared by
- * xpc_process_disconnect(), and if set, XPC_C_WDISCONNECT is cleared by
- * xpc_disconnect_wait().
- *
- * THE CHANNEL IS TO BE LOCKED BY THE CALLER AND WILL REMAIN LOCKED UPON RETURN.
- */
-void
-xpc_disconnect_channel(const int line, struct xpc_channel *ch,
-			enum xpc_retval reason, unsigned long *irq_flags)
-{
-	u32 channel_was_connected = (ch->flags & XPC_C_CONNECTED);
-
-
-	DBUG_ON(!spin_is_locked(&ch->lock));
-
-	if (ch->flags & (XPC_C_DISCONNECTING | XPC_C_DISCONNECTED)) {
-		return;
-	}
-	DBUG_ON(!(ch->flags & (XPC_C_CONNECTING | XPC_C_CONNECTED)));
-
-	dev_dbg(xpc_chan, "reason=%d, line=%d, partid=%d, channel=%d\n",
-		reason, line, ch->partid, ch->number);
-
-	XPC_SET_REASON(ch, reason, line);
-
-	ch->flags |= (XPC_C_CLOSEREQUEST | XPC_C_DISCONNECTING);
-	/* some of these may not have been set */
-	ch->flags &= ~(XPC_C_OPENREQUEST | XPC_C_OPENREPLY |
-			XPC_C_ROPENREQUEST | XPC_C_ROPENREPLY |
-			XPC_C_CONNECTING | XPC_C_CONNECTED);
-
-	xpc_IPI_send_closerequest(ch, irq_flags);
-
-	if (channel_was_connected) {
-		ch->flags |= XPC_C_WASCONNECTED;
-	}
-
-	spin_unlock_irqrestore(&ch->lock, *irq_flags);
-
-	/* wake all idle kthreads so they can exit */
-	if (atomic_read(&ch->kthreads_idle) > 0) {
-		wake_up_all(&ch->idle_wq);
-
-	} else if ((ch->flags & XPC_C_CONNECTEDCALLOUT_MADE) &&
-			!(ch->flags & XPC_C_DISCONNECTINGCALLOUT)) {
-		/* start a kthread that will do the xpcDisconnecting callout */
-		xpc_create_kthreads(ch, 1, 1);
-	}
-
-	/* wake those waiting to allocate an entry from the local msg queue */
-	if (atomic_read(&ch->n_on_msg_allocate_wq) > 0) {
-		wake_up(&ch->msg_allocate_wq);
-	}
-
-	spin_lock_irqsave(&ch->lock, *irq_flags);
-}
-
-
-void
-xpc_disconnect_callout(struct xpc_channel *ch, enum xpc_retval reason)
-{
-	/*
-	 * Let the channel's registerer know that the channel is being
-	 * disconnected. We don't want to do this if the registerer was never
-	 * informed of a connection being made.
-	 */
-
-	if (ch->func != NULL) {
-		dev_dbg(xpc_chan, "ch->func() called, reason=%d, partid=%d, "
-			"channel=%d\n", reason, ch->partid, ch->number);
-
-		ch->func(reason, ch->partid, ch->number, NULL, ch->key);
-
-		dev_dbg(xpc_chan, "ch->func() returned, reason=%d, partid=%d, "
-			"channel=%d\n", reason, ch->partid, ch->number);
-	}
-}
-
-
-/*
- * Wait for a message entry to become available for the specified channel,
- * but don't wait any longer than 1 jiffy.
- */
-static enum xpc_retval
-xpc_allocate_msg_wait(struct xpc_channel *ch)
-{
-	enum xpc_retval ret;
-
-
-	if (ch->flags & XPC_C_DISCONNECTING) {
-		DBUG_ON(ch->reason == xpcInterrupted);  // >>> Is this true?
-		return ch->reason;
-	}
-
-	atomic_inc(&ch->n_on_msg_allocate_wq);
-	ret = interruptible_sleep_on_timeout(&ch->msg_allocate_wq, 1);
-	atomic_dec(&ch->n_on_msg_allocate_wq);
-
-	if (ch->flags & XPC_C_DISCONNECTING) {
-		ret = ch->reason;
-		DBUG_ON(ch->reason == xpcInterrupted);  // >>> Is this true?
-	} else if (ret == 0) {
-		ret = xpcTimeout;
-	} else {
-		ret = xpcInterrupted;
-	}
-
-	return ret;
-}
-
-
-/*
- * Allocate an entry for a message from the message queue associated with the
- * specified channel.
- */
-static enum xpc_retval
-xpc_allocate_msg(struct xpc_channel *ch, u32 flags,
-			struct xpc_msg **address_of_msg)
-{
-	struct xpc_msg *msg;
-	enum xpc_retval ret;
-	s64 put;
-
-
-	/* this reference will be dropped in xpc_send_msg() */
-	xpc_msgqueue_ref(ch);
-
-	if (ch->flags & XPC_C_DISCONNECTING) {
-		xpc_msgqueue_deref(ch);
-		return ch->reason;
-	}
-	if (!(ch->flags & XPC_C_CONNECTED)) {
-		xpc_msgqueue_deref(ch);
-		return xpcNotConnected;
-	}
-
-
-	/*
-	 * Get the next available message entry from the local message queue.
-	 * If none are available, we'll make sure that we grab the latest
-	 * GP values.
-	 */
-	ret = xpcTimeout;
-
-	while (1) {
-
-		put = (volatile s64) ch->w_local_GP.put;
-		if (put - (volatile s64) ch->w_remote_GP.get <
-							ch->local_nentries) {
-
-			/* There are available message entries. We need to try
-			 * to secure one for ourselves. We'll do this by trying
-			 * to increment w_local_GP.put as long as someone else
-			 * doesn't beat us to it. If they do, we'll have to
-			 * try again.
-		 	 */
-			if (cmpxchg(&ch->w_local_GP.put, put, put + 1) ==
-									put) {
-				/* we got the entry referenced by put */
-				break;
-			}
-			continue;	/* try again */
-		}
-
-
-		/*
-		 * There aren't any available msg entries at this time.
-		 *
-		 * In waiting for a message entry to become available,
-		 * we set a timeout in case the other side is not
-		 * sending completion IPIs. This lets us fake an IPI
-		 * that will cause the IPI handler to fetch the latest
-		 * GP values as if an IPI was sent by the other side.
-		 */
-		if (ret == xpcTimeout) {
-			xpc_IPI_send_local_msgrequest(ch);
-		}
-
-		if (flags & XPC_NOWAIT) {
-			xpc_msgqueue_deref(ch);
-			return xpcNoWait;
-		}
-
-		ret = xpc_allocate_msg_wait(ch);
-		if (ret != xpcInterrupted && ret != xpcTimeout) {
-			xpc_msgqueue_deref(ch);
-			return ret;
-		}
-	}
-
-
-	/* get the message's address and initialize it */
-	msg = (struct xpc_msg *) ((u64) ch->local_msgqueue +
-				(put % ch->local_nentries) * ch->msg_size);
-
-
-	DBUG_ON(msg->flags != 0);
-	msg->number = put;
-
-	dev_dbg(xpc_chan, "w_local_GP.put changed to %ld; msg=0x%p, "
-		"msg_number=%ld, partid=%d, channel=%d\n", put + 1,
-		(void *) msg, msg->number, ch->partid, ch->number);
-
-	*address_of_msg = msg;
-
-	return xpcSuccess;
-}
-
-
-/*
- * Allocate an entry for a message from the message queue associated with the
- * specified channel. NOTE that this routine can sleep waiting for a message
- * entry to become available. To not sleep, pass in the XPC_NOWAIT flag.
- *
- * Arguments:
- *
- *	partid - ID of partition to which the channel is connected.
- *	ch_number - channel #.
- *	flags - see xpc.h for valid flags.
- *	payload - address of the allocated payload area pointer (filled in on
- * 	          return) in which the user-defined message is constructed.
- */
-enum xpc_retval
-xpc_initiate_allocate(partid_t partid, int ch_number, u32 flags, void **payload)
-{
-	struct xpc_partition *part = &xpc_partitions[partid];
-	enum xpc_retval ret = xpcUnknownReason;
-	struct xpc_msg *msg = NULL;
-
-
-	DBUG_ON(partid <= 0 || partid >= XP_MAX_PARTITIONS);
-	DBUG_ON(ch_number < 0 || ch_number >= part->nchannels);
-
-	*payload = NULL;
-
-	if (xpc_part_ref(part)) {
-		ret = xpc_allocate_msg(&part->channels[ch_number], flags, &msg);
-		xpc_part_deref(part);
-
-		if (msg != NULL) {
-			*payload = &msg->payload;
-		}
-	}
-
-	return ret;
-}
-
-
-/*
- * Now we actually send the messages that are ready to be sent by advancing
- * the local message queue's Put value and then send an IPI to the recipient
- * partition.
- */
-static void
-xpc_send_msgs(struct xpc_channel *ch, s64 initial_put)
-{
-	struct xpc_msg *msg;
-	s64 put = initial_put + 1;
-	int send_IPI = 0;
-
-
-	while (1) {
-
-		while (1) {
-			if (put == (volatile s64) ch->w_local_GP.put) {
-				break;
-			}
-
-			msg = (struct xpc_msg *) ((u64) ch->local_msgqueue +
-			       (put % ch->local_nentries) * ch->msg_size);
-
-			if (!(msg->flags & XPC_M_READY)) {
-				break;
-			}
-
-			put++;
-		}
-
-		if (put == initial_put) {
-			/* nothing's changed */
-			break;
-		}
-
-		if (cmpxchg_rel(&ch->local_GP->put, initial_put, put) !=
-								initial_put) {
-			/* someone else beat us to it */
-			DBUG_ON((volatile s64) ch->local_GP->put < initial_put);
-			break;
-		}
-
-		/* we just set the new value of local_GP->put */
-
-		dev_dbg(xpc_chan, "local_GP->put changed to %ld, partid=%d, "
-			"channel=%d\n", put, ch->partid, ch->number);
-
-		send_IPI = 1;
-
-		/*
-		 * We need to ensure that the message referenced by
-		 * local_GP->put is not XPC_M_READY or that local_GP->put
-		 * equals w_local_GP.put, so we'll go have a look.
-		 */
-		initial_put = put;
-	}
-
-	if (send_IPI) {
-		xpc_IPI_send_msgrequest(ch);
-	}
-}
-
-
-/*
- * Common code that does the actual sending of the message by advancing the
- * local message queue's Put value and sends an IPI to the partition the
- * message is being sent to.
- */
-static enum xpc_retval
-xpc_send_msg(struct xpc_channel *ch, struct xpc_msg *msg, u8 notify_type,
-			xpc_notify_func func, void *key)
-{
-	enum xpc_retval ret = xpcSuccess;
-	struct xpc_notify *notify = notify;
-	s64 put, msg_number = msg->number;
-
-
-	DBUG_ON(notify_type == XPC_N_CALL && func == NULL);
-	DBUG_ON((((u64) msg - (u64) ch->local_msgqueue) / ch->msg_size) !=
-					msg_number % ch->local_nentries);
-	DBUG_ON(msg->flags & XPC_M_READY);
-
-	if (ch->flags & XPC_C_DISCONNECTING) {
-		/* drop the reference grabbed in xpc_allocate_msg() */
-		xpc_msgqueue_deref(ch);
-		return ch->reason;
-	}
-
-	if (notify_type != 0) {
-		/*
-		 * Tell the remote side to send an ACK interrupt when the
-		 * message has been delivered.
-		 */
-		msg->flags |= XPC_M_INTERRUPT;
-
-		atomic_inc(&ch->n_to_notify);
-
-		notify = &ch->notify_queue[msg_number % ch->local_nentries];
-		notify->func = func;
-		notify->key = key;
-		notify->type = notify_type;
-
-		// >>> is a mb() needed here?
-
-		if (ch->flags & XPC_C_DISCONNECTING) {
-			/*
-			 * An error occurred between our last error check and
-			 * this one. We will try to clear the type field from
-			 * the notify entry. If we succeed then
-			 * xpc_disconnect_channel() didn't already process
-			 * the notify entry.
-			 */
-			if (cmpxchg(&notify->type, notify_type, 0) ==
-								notify_type) {
-				atomic_dec(&ch->n_to_notify);
-				ret = ch->reason;
-			}
-
-			/* drop the reference grabbed in xpc_allocate_msg() */
-			xpc_msgqueue_deref(ch);
-			return ret;
-		}
-	}
-
-	msg->flags |= XPC_M_READY;
-
-	/*
-	 * The preceding store of msg->flags must occur before the following
-	 * load of ch->local_GP->put.
-	 */
-	mb();
-
-	/* see if the message is next in line to be sent, if so send it */
-
-	put = ch->local_GP->put;
-	if (put == msg_number) {
-		xpc_send_msgs(ch, put);
-	}
-
-	/* drop the reference grabbed in xpc_allocate_msg() */
-	xpc_msgqueue_deref(ch);
-	return ret;
-}
-
-
-/*
- * Send a message previously allocated using xpc_initiate_allocate() on the
- * specified channel connected to the specified partition.
- *
- * This routine will not wait for the message to be received, nor will
- * notification be given when it does happen. Once this routine has returned
- * the message entry allocated via xpc_initiate_allocate() is no longer
- * accessable to the caller.
- *
- * This routine, although called by users, does not call xpc_part_ref() to
- * ensure that the partition infrastructure is in place. It relies on the
- * fact that we called xpc_msgqueue_ref() in xpc_allocate_msg().
- *
- * Arguments:
- *
- *	partid - ID of partition to which the channel is connected.
- *	ch_number - channel # to send message on.
- *	payload - pointer to the payload area allocated via
- *			xpc_initiate_allocate().
- */
-enum xpc_retval
-xpc_initiate_send(partid_t partid, int ch_number, void *payload)
-{
-	struct xpc_partition *part = &xpc_partitions[partid];
-	struct xpc_msg *msg = XPC_MSG_ADDRESS(payload);
-	enum xpc_retval ret;
-
-
-	dev_dbg(xpc_chan, "msg=0x%p, partid=%d, channel=%d\n", (void *) msg,
-		partid, ch_number);
-
-	DBUG_ON(partid <= 0 || partid >= XP_MAX_PARTITIONS);
-	DBUG_ON(ch_number < 0 || ch_number >= part->nchannels);
-	DBUG_ON(msg == NULL);
-
-	ret = xpc_send_msg(&part->channels[ch_number], msg, 0, NULL, NULL);
-
-	return ret;
-}
-
-
-/*
- * Send a message previously allocated using xpc_initiate_allocate on the
- * specified channel connected to the specified partition.
- *
- * This routine will not wait for the message to be sent. Once this routine
- * has returned the message entry allocated via xpc_initiate_allocate() is no
- * longer accessable to the caller.
- *
- * Once the remote end of the channel has received the message, the function
- * passed as an argument to xpc_initiate_send_notify() will be called. This
- * allows the sender to free up or re-use any buffers referenced by the
- * message, but does NOT mean the message has been processed at the remote
- * end by a receiver.
- *
- * If this routine returns an error, the caller's function will NOT be called.
- *
- * This routine, although called by users, does not call xpc_part_ref() to
- * ensure that the partition infrastructure is in place. It relies on the
- * fact that we called xpc_msgqueue_ref() in xpc_allocate_msg().
- *
- * Arguments:
- *
- *	partid - ID of partition to which the channel is connected.
- *	ch_number - channel # to send message on.
- *	payload - pointer to the payload area allocated via
- *			xpc_initiate_allocate().
- *	func - function to call with asynchronous notification of message
- *		  receipt. THIS FUNCTION MUST BE NON-BLOCKING.
- *	key - user-defined key to be passed to the function when it's called.
- */
-enum xpc_retval
-xpc_initiate_send_notify(partid_t partid, int ch_number, void *payload,
-				xpc_notify_func func, void *key)
-{
-	struct xpc_partition *part = &xpc_partitions[partid];
-	struct xpc_msg *msg = XPC_MSG_ADDRESS(payload);
-	enum xpc_retval ret;
-
-
-	dev_dbg(xpc_chan, "msg=0x%p, partid=%d, channel=%d\n", (void *) msg,
-		partid, ch_number);
-
-	DBUG_ON(partid <= 0 || partid >= XP_MAX_PARTITIONS);
-	DBUG_ON(ch_number < 0 || ch_number >= part->nchannels);
-	DBUG_ON(msg == NULL);
-	DBUG_ON(func == NULL);
-
-	ret = xpc_send_msg(&part->channels[ch_number], msg, XPC_N_CALL,
-								func, key);
-	return ret;
-}
-
-
-static struct xpc_msg *
-xpc_pull_remote_msg(struct xpc_channel *ch, s64 get)
-{
-	struct xpc_partition *part = &xpc_partitions[ch->partid];
-	struct xpc_msg *remote_msg, *msg;
-	u32 msg_index, nmsgs;
-	u64 msg_offset;
-	enum xpc_retval ret;
-
-
-	if (mutex_lock_interruptible(&ch->msg_to_pull_mutex) != 0) {
-		/* we were interrupted by a signal */
-		return NULL;
-	}
-
-	while (get >= ch->next_msg_to_pull) {
-
-		/* pull as many messages as are ready and able to be pulled */
-
-		msg_index = ch->next_msg_to_pull % ch->remote_nentries;
-
-		DBUG_ON(ch->next_msg_to_pull >=
-					(volatile s64) ch->w_remote_GP.put);
-		nmsgs =  (volatile s64) ch->w_remote_GP.put -
-						ch->next_msg_to_pull;
-		if (msg_index + nmsgs > ch->remote_nentries) {
-			/* ignore the ones that wrap the msg queue for now */
-			nmsgs = ch->remote_nentries - msg_index;
-		}
-
-		msg_offset = msg_index * ch->msg_size;
-		msg = (struct xpc_msg *) ((u64) ch->remote_msgqueue +
-								msg_offset);
-		remote_msg = (struct xpc_msg *) (ch->remote_msgqueue_pa +
-								msg_offset);
-
-		if ((ret = xpc_pull_remote_cachelines(part, msg, remote_msg,
-				nmsgs * ch->msg_size)) != xpcSuccess) {
-
-			dev_dbg(xpc_chan, "failed to pull %d msgs starting with"
-				" msg %ld from partition %d, channel=%d, "
-				"ret=%d\n", nmsgs, ch->next_msg_to_pull,
-				ch->partid, ch->number, ret);
-
-			XPC_DEACTIVATE_PARTITION(part, ret);
-
-			mutex_unlock(&ch->msg_to_pull_mutex);
-			return NULL;
-		}
-
-		mb();	/* >>> this may not be needed, we're not sure */
-
-		ch->next_msg_to_pull += nmsgs;
-	}
-
-	mutex_unlock(&ch->msg_to_pull_mutex);
-
-	/* return the message we were looking for */
-	msg_offset = (get % ch->remote_nentries) * ch->msg_size;
-	msg = (struct xpc_msg *) ((u64) ch->remote_msgqueue + msg_offset);
-
-	return msg;
-}
-
-
-/*
- * Get a message to be delivered.
- */
-static struct xpc_msg *
-xpc_get_deliverable_msg(struct xpc_channel *ch)
-{
-	struct xpc_msg *msg = NULL;
-	s64 get;
-
-
-	do {
-		if ((volatile u32) ch->flags & XPC_C_DISCONNECTING) {
-			break;
-		}
-
-		get = (volatile s64) ch->w_local_GP.get;
-		if (get == (volatile s64) ch->w_remote_GP.put) {
-			break;
-		}
-
-		/* There are messages waiting to be pulled and delivered.
-		 * We need to try to secure one for ourselves. We'll do this
-		 * by trying to increment w_local_GP.get and hope that no one
-		 * else beats us to it. If they do, we'll we'll simply have
-		 * to try again for the next one.
-	 	 */
-
-		if (cmpxchg(&ch->w_local_GP.get, get, get + 1) == get) {
-			/* we got the entry referenced by get */
-
-			dev_dbg(xpc_chan, "w_local_GP.get changed to %ld, "
-				"partid=%d, channel=%d\n", get + 1,
-				ch->partid, ch->number);
-
-			/* pull the message from the remote partition */
-
-			msg = xpc_pull_remote_msg(ch, get);
-
-			DBUG_ON(msg != NULL && msg->number != get);
-			DBUG_ON(msg != NULL && (msg->flags & XPC_M_DONE));
-			DBUG_ON(msg != NULL && !(msg->flags & XPC_M_READY));
-
-			break;
-		}
-
-	} while (1);
-
-	return msg;
-}
-
-
-/*
- * Deliver a message to its intended recipient.
- */
-void
-xpc_deliver_msg(struct xpc_channel *ch)
-{
-	struct xpc_msg *msg;
-
-
-	if ((msg = xpc_get_deliverable_msg(ch)) != NULL) {
-
-		/*
-		 * This ref is taken to protect the payload itself from being
-		 * freed before the user is finished with it, which the user
-		 * indicates by calling xpc_initiate_received().
-		 */
-		xpc_msgqueue_ref(ch);
-
-		atomic_inc(&ch->kthreads_active);
-
-		if (ch->func != NULL) {
-			dev_dbg(xpc_chan, "ch->func() called, msg=0x%p, "
-				"msg_number=%ld, partid=%d, channel=%d\n",
-				(void *) msg, msg->number, ch->partid,
-				ch->number);
-
-			/* deliver the message to its intended recipient */
-			ch->func(xpcMsgReceived, ch->partid, ch->number,
-					&msg->payload, ch->key);
-
-			dev_dbg(xpc_chan, "ch->func() returned, msg=0x%p, "
-				"msg_number=%ld, partid=%d, channel=%d\n",
-				(void *) msg, msg->number, ch->partid,
-				ch->number);
-		}
-
-		atomic_dec(&ch->kthreads_active);
-	}
-}
-
-
-/*
- * Now we actually acknowledge the messages that have been delivered and ack'd
- * by advancing the cached remote message queue's Get value and if requested
- * send an IPI to the message sender's partition.
- */
-static void
-xpc_acknowledge_msgs(struct xpc_channel *ch, s64 initial_get, u8 msg_flags)
-{
-	struct xpc_msg *msg;
-	s64 get = initial_get + 1;
-	int send_IPI = 0;
-
-
-	while (1) {
-
-		while (1) {
-			if (get == (volatile s64) ch->w_local_GP.get) {
-				break;
-			}
-
-			msg = (struct xpc_msg *) ((u64) ch->remote_msgqueue +
-			       (get % ch->remote_nentries) * ch->msg_size);
-
-			if (!(msg->flags & XPC_M_DONE)) {
-				break;
-			}
-
-			msg_flags |= msg->flags;
-			get++;
-		}
-
-		if (get == initial_get) {
-			/* nothing's changed */
-			break;
-		}
-
-		if (cmpxchg_rel(&ch->local_GP->get, initial_get, get) !=
-								initial_get) {
-			/* someone else beat us to it */
-			DBUG_ON((volatile s64) ch->local_GP->get <=
-								initial_get);
-			break;
-		}
-
-		/* we just set the new value of local_GP->get */
-
-		dev_dbg(xpc_chan, "local_GP->get changed to %ld, partid=%d, "
-			"channel=%d\n", get, ch->partid, ch->number);
-
-		send_IPI = (msg_flags & XPC_M_INTERRUPT);
-
-		/*
-		 * We need to ensure that the message referenced by
-		 * local_GP->get is not XPC_M_DONE or that local_GP->get
-		 * equals w_local_GP.get, so we'll go have a look.
-		 */
-		initial_get = get;
-	}
-
-	if (send_IPI) {
-		xpc_IPI_send_msgrequest(ch);
-	}
-}
-
-
-/*
- * Acknowledge receipt of a delivered message.
- *
- * If a message has XPC_M_INTERRUPT set, send an interrupt to the partition
- * that sent the message.
- *
- * This function, although called by users, does not call xpc_part_ref() to
- * ensure that the partition infrastructure is in place. It relies on the
- * fact that we called xpc_msgqueue_ref() in xpc_deliver_msg().
- *
- * Arguments:
- *
- *	partid - ID of partition to which the channel is connected.
- *	ch_number - channel # message received on.
- *	payload - pointer to the payload area allocated via
- *			xpc_initiate_allocate().
- */
-void
-xpc_initiate_received(partid_t partid, int ch_number, void *payload)
-{
-	struct xpc_partition *part = &xpc_partitions[partid];
-	struct xpc_channel *ch;
-	struct xpc_msg *msg = XPC_MSG_ADDRESS(payload);
-	s64 get, msg_number = msg->number;
-
-
-	DBUG_ON(partid <= 0 || partid >= XP_MAX_PARTITIONS);
-	DBUG_ON(ch_number < 0 || ch_number >= part->nchannels);
-
-	ch = &part->channels[ch_number];
-
-	dev_dbg(xpc_chan, "msg=0x%p, msg_number=%ld, partid=%d, channel=%d\n",
-		(void *) msg, msg_number, ch->partid, ch->number);
-
-	DBUG_ON((((u64) msg - (u64) ch->remote_msgqueue) / ch->msg_size) !=
-					msg_number % ch->remote_nentries);
-	DBUG_ON(msg->flags & XPC_M_DONE);
-
-	msg->flags |= XPC_M_DONE;
-
-	/*
-	 * The preceding store of msg->flags must occur before the following
-	 * load of ch->local_GP->get.
-	 */
-	mb();
-
-	/*
-	 * See if this message is next in line to be acknowledged as having
-	 * been delivered.
-	 */
-	get = ch->local_GP->get;
-	if (get == msg_number) {
-		xpc_acknowledge_msgs(ch, get, msg->flags);
-	}
-
-	/* the call to xpc_msgqueue_ref() was done by xpc_deliver_msg()  */
-	xpc_msgqueue_deref(ch);
-}
-