72fdbdce3d
Spelling and apostrophe fixes in arch/ia64/. Signed-off-by: Simon Arlott <simon@fire.lp0.eu> Signed-off-by: Tony Luck <tony.luck@intel.com>
2380 lines
61 KiB
C
2380 lines
61 KiB
C
/*
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* This file is subject to the terms and conditions of the GNU General Public
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* License. See the file "COPYING" in the main directory of this archive
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* for more details.
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*
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* Copyright (c) 2004-2006 Silicon Graphics, Inc. All Rights Reserved.
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*/
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/*
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* Cross Partition Communication (XPC) channel support.
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*
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* This is the part of XPC that manages the channels and
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* sends/receives messages across them to/from other partitions.
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*
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*/
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#include <linux/kernel.h>
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#include <linux/init.h>
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#include <linux/sched.h>
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#include <linux/cache.h>
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#include <linux/interrupt.h>
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#include <linux/mutex.h>
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#include <linux/completion.h>
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#include <asm/sn/bte.h>
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#include <asm/sn/sn_sal.h>
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#include <asm/sn/xpc.h>
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/*
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* Guarantee that the kzalloc'd memory is cacheline aligned.
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*/
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static void *
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xpc_kzalloc_cacheline_aligned(size_t size, gfp_t flags, void **base)
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{
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/* see if kzalloc will give us cachline aligned memory by default */
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*base = kzalloc(size, flags);
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if (*base == NULL) {
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return NULL;
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}
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if ((u64) *base == L1_CACHE_ALIGN((u64) *base)) {
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return *base;
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}
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kfree(*base);
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/* nope, we'll have to do it ourselves */
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*base = kzalloc(size + L1_CACHE_BYTES, flags);
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if (*base == NULL) {
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return NULL;
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}
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return (void *) L1_CACHE_ALIGN((u64) *base);
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}
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/*
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* Set up the initial values for the XPartition Communication channels.
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*/
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static void
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xpc_initialize_channels(struct xpc_partition *part, partid_t partid)
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{
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int ch_number;
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struct xpc_channel *ch;
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for (ch_number = 0; ch_number < part->nchannels; ch_number++) {
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ch = &part->channels[ch_number];
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ch->partid = partid;
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ch->number = ch_number;
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ch->flags = XPC_C_DISCONNECTED;
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ch->local_GP = &part->local_GPs[ch_number];
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ch->local_openclose_args =
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&part->local_openclose_args[ch_number];
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atomic_set(&ch->kthreads_assigned, 0);
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atomic_set(&ch->kthreads_idle, 0);
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atomic_set(&ch->kthreads_active, 0);
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atomic_set(&ch->references, 0);
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atomic_set(&ch->n_to_notify, 0);
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spin_lock_init(&ch->lock);
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mutex_init(&ch->msg_to_pull_mutex);
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init_completion(&ch->wdisconnect_wait);
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atomic_set(&ch->n_on_msg_allocate_wq, 0);
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init_waitqueue_head(&ch->msg_allocate_wq);
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init_waitqueue_head(&ch->idle_wq);
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}
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}
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/*
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* Setup the infrastructure necessary to support XPartition Communication
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* between the specified remote partition and the local one.
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*/
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enum xpc_retval
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xpc_setup_infrastructure(struct xpc_partition *part)
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{
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int ret, cpuid;
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struct timer_list *timer;
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partid_t partid = XPC_PARTID(part);
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/*
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* Zero out MOST of the entry for this partition. Only the fields
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* starting with `nchannels' will be zeroed. The preceding fields must
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* remain `viable' across partition ups and downs, since they may be
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* referenced during this memset() operation.
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*/
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memset(&part->nchannels, 0, sizeof(struct xpc_partition) -
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offsetof(struct xpc_partition, nchannels));
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/*
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* Allocate all of the channel structures as a contiguous chunk of
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* memory.
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*/
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part->channels = kzalloc(sizeof(struct xpc_channel) * XPC_NCHANNELS,
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GFP_KERNEL);
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if (part->channels == NULL) {
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dev_err(xpc_chan, "can't get memory for channels\n");
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return xpcNoMemory;
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}
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part->nchannels = XPC_NCHANNELS;
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/* allocate all the required GET/PUT values */
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part->local_GPs = xpc_kzalloc_cacheline_aligned(XPC_GP_SIZE,
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GFP_KERNEL, &part->local_GPs_base);
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if (part->local_GPs == NULL) {
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kfree(part->channels);
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part->channels = NULL;
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dev_err(xpc_chan, "can't get memory for local get/put "
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"values\n");
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return xpcNoMemory;
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}
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part->remote_GPs = xpc_kzalloc_cacheline_aligned(XPC_GP_SIZE,
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GFP_KERNEL, &part->remote_GPs_base);
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if (part->remote_GPs == NULL) {
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dev_err(xpc_chan, "can't get memory for remote get/put "
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"values\n");
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kfree(part->local_GPs_base);
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part->local_GPs = NULL;
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kfree(part->channels);
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part->channels = NULL;
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return xpcNoMemory;
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}
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/* allocate all the required open and close args */
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part->local_openclose_args = xpc_kzalloc_cacheline_aligned(
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XPC_OPENCLOSE_ARGS_SIZE, GFP_KERNEL,
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&part->local_openclose_args_base);
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if (part->local_openclose_args == NULL) {
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dev_err(xpc_chan, "can't get memory for local connect args\n");
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kfree(part->remote_GPs_base);
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part->remote_GPs = NULL;
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kfree(part->local_GPs_base);
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part->local_GPs = NULL;
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kfree(part->channels);
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part->channels = NULL;
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return xpcNoMemory;
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}
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part->remote_openclose_args = xpc_kzalloc_cacheline_aligned(
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XPC_OPENCLOSE_ARGS_SIZE, GFP_KERNEL,
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&part->remote_openclose_args_base);
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if (part->remote_openclose_args == NULL) {
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dev_err(xpc_chan, "can't get memory for remote connect args\n");
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kfree(part->local_openclose_args_base);
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part->local_openclose_args = NULL;
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kfree(part->remote_GPs_base);
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part->remote_GPs = NULL;
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kfree(part->local_GPs_base);
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part->local_GPs = NULL;
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kfree(part->channels);
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part->channels = NULL;
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return xpcNoMemory;
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}
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xpc_initialize_channels(part, partid);
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atomic_set(&part->nchannels_active, 0);
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atomic_set(&part->nchannels_engaged, 0);
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/* local_IPI_amo were set to 0 by an earlier memset() */
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/* Initialize this partitions AMO_t structure */
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part->local_IPI_amo_va = xpc_IPI_init(partid);
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spin_lock_init(&part->IPI_lock);
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atomic_set(&part->channel_mgr_requests, 1);
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init_waitqueue_head(&part->channel_mgr_wq);
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sprintf(part->IPI_owner, "xpc%02d", partid);
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ret = request_irq(SGI_XPC_NOTIFY, xpc_notify_IRQ_handler, IRQF_SHARED,
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part->IPI_owner, (void *) (u64) partid);
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if (ret != 0) {
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dev_err(xpc_chan, "can't register NOTIFY IRQ handler, "
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"errno=%d\n", -ret);
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kfree(part->remote_openclose_args_base);
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part->remote_openclose_args = NULL;
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kfree(part->local_openclose_args_base);
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part->local_openclose_args = NULL;
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kfree(part->remote_GPs_base);
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part->remote_GPs = NULL;
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kfree(part->local_GPs_base);
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part->local_GPs = NULL;
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kfree(part->channels);
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part->channels = NULL;
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return xpcLackOfResources;
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}
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/* Setup a timer to check for dropped IPIs */
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timer = &part->dropped_IPI_timer;
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init_timer(timer);
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timer->function = (void (*)(unsigned long)) xpc_dropped_IPI_check;
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timer->data = (unsigned long) part;
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timer->expires = jiffies + XPC_P_DROPPED_IPI_WAIT;
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add_timer(timer);
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/*
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* With the setting of the partition setup_state to XPC_P_SETUP, we're
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* declaring that this partition is ready to go.
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*/
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part->setup_state = XPC_P_SETUP;
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/*
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* Setup the per partition specific variables required by the
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* remote partition to establish channel connections with us.
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*
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* The setting of the magic # indicates that these per partition
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* specific variables are ready to be used.
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*/
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xpc_vars_part[partid].GPs_pa = __pa(part->local_GPs);
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xpc_vars_part[partid].openclose_args_pa =
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__pa(part->local_openclose_args);
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xpc_vars_part[partid].IPI_amo_pa = __pa(part->local_IPI_amo_va);
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cpuid = raw_smp_processor_id(); /* any CPU in this partition will do */
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xpc_vars_part[partid].IPI_nasid = cpuid_to_nasid(cpuid);
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xpc_vars_part[partid].IPI_phys_cpuid = cpu_physical_id(cpuid);
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xpc_vars_part[partid].nchannels = part->nchannels;
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xpc_vars_part[partid].magic = XPC_VP_MAGIC1;
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return xpcSuccess;
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}
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/*
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* Create a wrapper that hides the underlying mechanism for pulling a cacheline
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* (or multiple cachelines) from a remote partition.
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*
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* src must be a cacheline aligned physical address on the remote partition.
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* dst must be a cacheline aligned virtual address on this partition.
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* cnt must be an cacheline sized
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*/
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static enum xpc_retval
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xpc_pull_remote_cachelines(struct xpc_partition *part, void *dst,
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const void *src, size_t cnt)
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{
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bte_result_t bte_ret;
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DBUG_ON((u64) src != L1_CACHE_ALIGN((u64) src));
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DBUG_ON((u64) dst != L1_CACHE_ALIGN((u64) dst));
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DBUG_ON(cnt != L1_CACHE_ALIGN(cnt));
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if (part->act_state == XPC_P_DEACTIVATING) {
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return part->reason;
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}
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bte_ret = xp_bte_copy((u64) src, (u64) dst, (u64) cnt,
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(BTE_NORMAL | BTE_WACQUIRE), NULL);
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if (bte_ret == BTE_SUCCESS) {
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return xpcSuccess;
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}
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dev_dbg(xpc_chan, "xp_bte_copy() from partition %d failed, ret=%d\n",
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XPC_PARTID(part), bte_ret);
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return xpc_map_bte_errors(bte_ret);
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}
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/*
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* Pull the remote per partition specific variables from the specified
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* partition.
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*/
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enum xpc_retval
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xpc_pull_remote_vars_part(struct xpc_partition *part)
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{
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u8 buffer[L1_CACHE_BYTES * 2];
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struct xpc_vars_part *pulled_entry_cacheline =
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(struct xpc_vars_part *) L1_CACHE_ALIGN((u64) buffer);
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struct xpc_vars_part *pulled_entry;
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u64 remote_entry_cacheline_pa, remote_entry_pa;
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partid_t partid = XPC_PARTID(part);
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enum xpc_retval ret;
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/* pull the cacheline that contains the variables we're interested in */
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DBUG_ON(part->remote_vars_part_pa !=
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L1_CACHE_ALIGN(part->remote_vars_part_pa));
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DBUG_ON(sizeof(struct xpc_vars_part) != L1_CACHE_BYTES / 2);
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remote_entry_pa = part->remote_vars_part_pa +
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sn_partition_id * sizeof(struct xpc_vars_part);
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remote_entry_cacheline_pa = (remote_entry_pa & ~(L1_CACHE_BYTES - 1));
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pulled_entry = (struct xpc_vars_part *) ((u64) pulled_entry_cacheline +
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(remote_entry_pa & (L1_CACHE_BYTES - 1)));
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ret = xpc_pull_remote_cachelines(part, pulled_entry_cacheline,
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(void *) remote_entry_cacheline_pa,
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L1_CACHE_BYTES);
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if (ret != xpcSuccess) {
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dev_dbg(xpc_chan, "failed to pull XPC vars_part from "
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"partition %d, ret=%d\n", partid, ret);
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return ret;
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}
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/* see if they've been set up yet */
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if (pulled_entry->magic != XPC_VP_MAGIC1 &&
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pulled_entry->magic != XPC_VP_MAGIC2) {
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if (pulled_entry->magic != 0) {
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dev_dbg(xpc_chan, "partition %d's XPC vars_part for "
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"partition %d has bad magic value (=0x%lx)\n",
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partid, sn_partition_id, pulled_entry->magic);
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return xpcBadMagic;
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}
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/* they've not been initialized yet */
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return xpcRetry;
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}
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if (xpc_vars_part[partid].magic == XPC_VP_MAGIC1) {
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/* validate the variables */
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if (pulled_entry->GPs_pa == 0 ||
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pulled_entry->openclose_args_pa == 0 ||
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pulled_entry->IPI_amo_pa == 0) {
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dev_err(xpc_chan, "partition %d's XPC vars_part for "
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"partition %d are not valid\n", partid,
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sn_partition_id);
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return xpcInvalidAddress;
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}
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/* the variables we imported look to be valid */
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part->remote_GPs_pa = pulled_entry->GPs_pa;
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part->remote_openclose_args_pa =
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pulled_entry->openclose_args_pa;
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part->remote_IPI_amo_va =
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(AMO_t *) __va(pulled_entry->IPI_amo_pa);
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part->remote_IPI_nasid = pulled_entry->IPI_nasid;
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part->remote_IPI_phys_cpuid = pulled_entry->IPI_phys_cpuid;
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if (part->nchannels > pulled_entry->nchannels) {
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part->nchannels = pulled_entry->nchannels;
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}
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/* let the other side know that we've pulled their variables */
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xpc_vars_part[partid].magic = XPC_VP_MAGIC2;
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}
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if (pulled_entry->magic == XPC_VP_MAGIC1) {
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return xpcRetry;
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}
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return xpcSuccess;
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}
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/*
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* Get the IPI flags and pull the openclose args and/or remote GPs as needed.
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*/
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static u64
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xpc_get_IPI_flags(struct xpc_partition *part)
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{
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unsigned long irq_flags;
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u64 IPI_amo;
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enum xpc_retval ret;
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/*
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* See if there are any IPI flags to be handled.
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*/
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spin_lock_irqsave(&part->IPI_lock, irq_flags);
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if ((IPI_amo = part->local_IPI_amo) != 0) {
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part->local_IPI_amo = 0;
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}
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spin_unlock_irqrestore(&part->IPI_lock, irq_flags);
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if (XPC_ANY_OPENCLOSE_IPI_FLAGS_SET(IPI_amo)) {
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ret = xpc_pull_remote_cachelines(part,
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part->remote_openclose_args,
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(void *) part->remote_openclose_args_pa,
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XPC_OPENCLOSE_ARGS_SIZE);
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if (ret != xpcSuccess) {
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XPC_DEACTIVATE_PARTITION(part, ret);
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dev_dbg(xpc_chan, "failed to pull openclose args from "
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"partition %d, ret=%d\n", XPC_PARTID(part),
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ret);
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/* don't bother processing IPIs anymore */
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IPI_amo = 0;
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}
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}
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if (XPC_ANY_MSG_IPI_FLAGS_SET(IPI_amo)) {
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ret = xpc_pull_remote_cachelines(part, part->remote_GPs,
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(void *) part->remote_GPs_pa,
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XPC_GP_SIZE);
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if (ret != xpcSuccess) {
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XPC_DEACTIVATE_PARTITION(part, ret);
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dev_dbg(xpc_chan, "failed to pull GPs from partition "
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"%d, ret=%d\n", XPC_PARTID(part), ret);
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/* don't bother processing IPIs anymore */
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IPI_amo = 0;
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}
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}
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return IPI_amo;
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}
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/*
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* Allocate the local message queue and the notify queue.
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*/
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static enum xpc_retval
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xpc_allocate_local_msgqueue(struct xpc_channel *ch)
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{
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unsigned long irq_flags;
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int nentries;
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size_t nbytes;
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// >>> may want to check for ch->flags & XPC_C_DISCONNECTING between
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// >>> iterations of the for-loop, bail if set?
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// >>> should we impose a minimum #of entries? like 4 or 8?
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for (nentries = ch->local_nentries; nentries > 0; nentries--) {
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nbytes = nentries * ch->msg_size;
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ch->local_msgqueue = xpc_kzalloc_cacheline_aligned(nbytes,
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GFP_KERNEL,
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&ch->local_msgqueue_base);
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if (ch->local_msgqueue == NULL) {
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continue;
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}
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nbytes = nentries * sizeof(struct xpc_notify);
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ch->notify_queue = kzalloc(nbytes, GFP_KERNEL);
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if (ch->notify_queue == NULL) {
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kfree(ch->local_msgqueue_base);
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ch->local_msgqueue = NULL;
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continue;
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}
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spin_lock_irqsave(&ch->lock, irq_flags);
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if (nentries < ch->local_nentries) {
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dev_dbg(xpc_chan, "nentries=%d local_nentries=%d, "
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"partid=%d, channel=%d\n", nentries,
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ch->local_nentries, ch->partid, ch->number);
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ch->local_nentries = nentries;
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}
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spin_unlock_irqrestore(&ch->lock, irq_flags);
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return xpcSuccess;
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}
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dev_dbg(xpc_chan, "can't get memory for local message queue and notify "
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"queue, partid=%d, channel=%d\n", ch->partid, ch->number);
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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(¬ify->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(®istration->mutex) == 0) {
|
|
return xpcRetry;
|
|
}
|
|
|
|
if (!XPC_CHANNEL_REGISTERED(ch->number)) {
|
|
mutex_unlock(®istration->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(®istration->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(®istration->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(®istration->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(¬ify->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);
|
|
}
|
|
|