static void
xpc_teardown_ch_structures(struct xpc_partition *part)
{
DBUG_ON(atomic_read(&part->nchannels_engaged) != 0);
DBUG_ON(atomic_read(&part->nchannels_active) != 0);
/*
*/
DBUG_ON(part->setup_state != XPC_P_SS_SETUP);
part->setup_state = XPC_P_SS_WTEARDOWN;
wait_event(part->teardown_wq, (atomic_read(&part->references) == 0));
/* */
xpc_arch_ops.teardown_ch_structures(part);
kfree(part->remote_openclose_args_base);
part->remote_openclose_args = NULL;
kfree(part->channels);
part->channels = NULL;
part->setup_state = XPC_P_SS_TORNDOWN;
}
/*
* Wait for a message entry to become available for the specified channel,
* but don't wait any longer than 1 jiffy.
*/
enum xp_retval
xpc_allocate_msg_wait(struct xpc_channel *ch)
{
enum xp_retval ret;
if (ch->flags & XPC_C_DISCONNECTING) {
DBUG_ON(ch->reason == xpInterrupted);
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 == xpInterrupted);
} else if (ret == 0) {
ret = xpTimeout;
} else {
ret = xpInterrupted;
}
return ret;
}
/*
* Teardown the channel structures necessary to support XPartition Communication
* between the specified remote partition and the local one.
*/
static void
xpc_teardown_ch_structures(struct xpc_partition *part)
{
DBUG_ON(atomic_read(&part->nchannels_engaged) != 0);
DBUG_ON(atomic_read(&part->nchannels_active) != 0);
/*
* Make this partition inaccessible to local processes by marking it
* as no longer setup. Then wait before proceeding with the teardown
* until all existing references cease.
*/
DBUG_ON(part->setup_state != XPC_P_SS_SETUP);
part->setup_state = XPC_P_SS_WTEARDOWN;
wait_event(part->teardown_wq, (atomic_read(&part->references) == 0));
/* now we can begin tearing down the infrastructure */
xpc_teardown_ch_structures_sn(part);
kfree(part->remote_openclose_args_base);
part->remote_openclose_args = NULL;
kfree(part->channels);
part->channels = NULL;
part->setup_state = XPC_P_SS_TORNDOWN;
}
/*
* Wait for a message entry to become available for the specified channel,
* but don't wait any longer than 1 jiffy.
*/
enum xp_retval
xpc_allocate_msg_wait(struct xpc_channel *ch)
{
enum xp_retval ret;
DEFINE_WAIT(wait);
if (ch->flags & XPC_C_DISCONNECTING) {
DBUG_ON(ch->reason == xpInterrupted);
return ch->reason;
}
atomic_inc(&ch->n_on_msg_allocate_wq);
prepare_to_wait(&ch->msg_allocate_wq, &wait, TASK_INTERRUPTIBLE);
ret = schedule_timeout(1);
finish_wait(&ch->msg_allocate_wq, &wait);
atomic_dec(&ch->n_on_msg_allocate_wq);
if (ch->flags & XPC_C_DISCONNECTING) {
ret = ch->reason;
DBUG_ON(ch->reason == xpInterrupted);
} else if (ret == 0) {
ret = xpTimeout;
} else {
ret = xpInterrupted;
}
return ret;
}
/*
* Timer function to enforce the timelimit on the partition disengage.
*/
static void
xpc_timeout_partition_disengage(unsigned long data)
{
struct xpc_partition *part = (struct xpc_partition *)data;
DBUG_ON(time_is_after_jiffies(part->disengage_timeout));
(void)xpc_partition_disengaged(part);
DBUG_ON(part->disengage_timeout != 0);
DBUG_ON(xpc_partition_engaged(XPC_PARTID(part)));
}
/*
* Timer function to enforce the timelimit on the partition disengage request.
*/
static void
xpc_timeout_partition_disengage_request(unsigned long data)
{
struct xpc_partition *part = (struct xpc_partition *)data;
DBUG_ON(time_before(jiffies, part->disengage_request_timeout));
(void)xpc_partition_disengaged(part);
DBUG_ON(part->disengage_request_timeout != 0);
DBUG_ON(xpc_partition_engaged(1UL << XPC_PARTID(part)) != 0);
}
/*
* When XPC HB determines that a partition has come up, it will create a new
* kthread and that kthread will call this function to attempt to set up the
* basic infrastructure used for Cross Partition Communication with the newly
* upped partition.
*
* The kthread that was created by XPC HB and which setup the XPC
* infrastructure will remain assigned to the partition becoming the channel
* manager for that partition until the partition is deactivating, at which
* time the kthread will teardown the XPC infrastructure and then exit.
*/
static int
xpc_activating(void *__partid)
{
short partid = (u64)__partid;
struct xpc_partition *part = &xpc_partitions[partid];
unsigned long irq_flags;
DBUG_ON(partid < 0 || partid >= xp_max_npartitions);
spin_lock_irqsave(&part->act_lock, irq_flags);
if (part->act_state == XPC_P_AS_DEACTIVATING) {
part->act_state = XPC_P_AS_INACTIVE;
spin_unlock_irqrestore(&part->act_lock, irq_flags);
part->remote_rp_pa = 0;
return 0;
}
/* indicate the thread is activating */
DBUG_ON(part->act_state != XPC_P_AS_ACTIVATION_REQ);
part->act_state = XPC_P_AS_ACTIVATING;
XPC_SET_REASON(part, 0, 0);
spin_unlock_irqrestore(&part->act_lock, irq_flags);
dev_dbg(xpc_part, "activating partition %d\n", partid);
xpc_allow_hb(partid);
if (xpc_setup_ch_structures(part) == xpSuccess) {
(void)xpc_part_ref(part); /* this will always succeed */
if (xpc_make_first_contact(part) == xpSuccess) {
xpc_mark_partition_active(part);
xpc_channel_mgr(part);
/* won't return until partition is deactivating */
}
xpc_part_deref(part);
xpc_teardown_ch_structures(part);
}
xpc_disallow_hb(partid);
xpc_mark_partition_inactive(part);
if (part->reason == xpReactivating) {
/* interrupting ourselves results in activating partition */
xpc_request_partition_reactivation(part);
}
return 0;
}
static void
xpc_process_connect(struct xpc_channel *ch, unsigned long *irq_flags)
{
enum xp_retval ret;
DBUG_ON(!spin_is_locked(&ch->lock));
if (!(ch->flags & XPC_C_OPENREQUEST) ||
!(ch->flags & XPC_C_ROPENREQUEST)) {
return;
}
DBUG_ON(!(ch->flags & XPC_C_CONNECTING));
if (!(ch->flags & XPC_C_SETUP)) {
spin_unlock_irqrestore(&ch->lock, *irq_flags);
ret = xpc_arch_ops.setup_msg_structures(ch);
spin_lock_irqsave(&ch->lock, *irq_flags);
if (ret != xpSuccess)
XPC_DISCONNECT_CHANNEL(ch, ret, irq_flags);
else
ch->flags |= XPC_C_SETUP;
if (ch->flags & XPC_C_DISCONNECTING)
return;
}
if (!(ch->flags & XPC_C_OPENREPLY)) {
ch->flags |= XPC_C_OPENREPLY;
xpc_arch_ops.send_chctl_openreply(ch, irq_flags);
}
if (!(ch->flags & XPC_C_ROPENREPLY))
return;
if (!(ch->flags & XPC_C_OPENCOMPLETE)) {
ch->flags |= (XPC_C_OPENCOMPLETE | XPC_C_CONNECTED);
xpc_arch_ops.send_chctl_opencomplete(ch, irq_flags);
}
if (!(ch->flags & XPC_C_ROPENCOMPLETE))
return;
dev_info(xpc_chan, "channel %d to partition %d connected\n",
ch->number, ch->partid);
ch->flags = (XPC_C_CONNECTED | XPC_C_SETUP);
}
void
xpc_initiate_received(short partid, int ch_number, void *payload)
{
struct xpc_partition *part = &xpc_partitions[partid];
struct xpc_channel *ch;
DBUG_ON(partid < 0 || partid >= xp_max_npartitions);
DBUG_ON(ch_number < 0 || ch_number >= part->nchannels);
ch = &part->channels[ch_number];
xpc_arch_ops.received_payload(ch, payload);
xpc_msgqueue_deref(ch);
}
/*
* Acknowledge receipt of a delivered message's payload.
*
* 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_payload().
*
* 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_send() or xpc_initiate_send_notify().
*/
void
xpc_initiate_received(short partid, int ch_number, void *payload)
{
struct xpc_partition *part = &xpc_partitions[partid];
struct xpc_channel *ch;
DBUG_ON(partid < 0 || partid >= xp_max_npartitions);
DBUG_ON(ch_number < 0 || ch_number >= part->nchannels);
ch = &part->channels[ch_number];
xpc_received_payload(ch, payload);
/* the call to xpc_msgqueue_ref() was done by xpc_deliver_payload() */
xpc_msgqueue_deref(ch);
}
/*
* Allocate msg_slots associated with the channel.
*/
static enum xp_retval
xpc_setup_msg_structures_uv(struct xpc_channel *ch)
{
static enum xp_retval ret;
struct xpc_channel_uv *ch_uv = &ch->sn.uv;
DBUG_ON(ch->flags & XPC_C_SETUP);
ch_uv->cached_notify_gru_mq_desc = kmalloc(sizeof(struct
gru_message_queue_desc),
GFP_KERNEL);
if (ch_uv->cached_notify_gru_mq_desc == NULL)
return xpNoMemory;
ret = xpc_allocate_send_msg_slot_uv(ch);
if (ret == xpSuccess) {
ret = xpc_allocate_recv_msg_slot_uv(ch);
if (ret != xpSuccess) {
kfree(ch_uv->send_msg_slots);
xpc_init_fifo_uv(&ch_uv->msg_slot_free_list);
}
}
return ret;
}
/*
* When XPC HB determines that a partition has come up, it will create a new
* kthread and that kthread will call this function to attempt to set up the
* basic infrastructure used for Cross Partition Communication with the newly
* upped partition.
*
* The kthread that was created by XPC HB and which setup the XPC
* infrastructure will remain assigned to the partition until the partition
* goes down. At which time the kthread will teardown the XPC infrastructure
* and then exit.
*
* XPC HB will put the remote partition's XPC per partition specific variables
* physical address into xpc_partitions[partid].remote_vars_part_pa prior to
* calling xpc_partition_up().
*/
static void
xpc_partition_up(struct xpc_partition *part)
{
DBUG_ON(part->channels != NULL);
dev_dbg(xpc_chan, "activating partition %d\n", XPC_PARTID(part));
if (xpc_setup_infrastructure(part) != xpSuccess)
return;
/*
* The kthread that XPC HB called us with will become the
* channel manager for this partition. It will not return
* back to XPC HB until the partition's XPC infrastructure
* has been dismantled.
*/
(void)xpc_part_ref(part); /* this will always succeed */
if (xpc_make_first_contact(part) == xpSuccess)
xpc_channel_mgr(part);
xpc_part_deref(part);
xpc_teardown_infrastructure(part);
}
void
xpc_disconnect(int ch_number)
{
struct xpc_registration *registration;
DBUG_ON(ch_number < 0 || ch_number >= XPC_MAX_NCHANNELS);
registration = &xpc_registrations[ch_number];
mutex_lock(®istration->mutex);
if (registration->func == NULL) {
mutex_unlock(®istration->mutex);
return;
}
registration->func = NULL;
registration->key = NULL;
registration->nentries = 0;
registration->entry_size = 0;
registration->assigned_limit = 0;
registration->idle_limit = 0;
xpc_interface.disconnect(ch_number);
mutex_unlock(®istration->mutex);
return;
}
void
xpc_activate_kthreads(struct xpc_channel *ch, int needed)
{
int idle = atomic_read(&ch->kthreads_idle);
int assigned = atomic_read(&ch->kthreads_assigned);
int wakeup;
DBUG_ON(needed <= 0);
if (idle > 0) {
wakeup = (needed > idle) ? idle : needed;
needed -= wakeup;
dev_dbg(xpc_chan, "wakeup %d idle kthreads, partid=%d, "
"channel=%d\n", wakeup, ch->partid, ch->number);
/* only wakeup the requested number of kthreads */
wake_up_nr(&ch->idle_wq, wakeup);
}
if (needed <= 0)
return;
if (needed + assigned > ch->kthreads_assigned_limit) {
needed = ch->kthreads_assigned_limit - assigned;
if (needed <= 0)
return;
}
dev_dbg(xpc_chan, "create %d new kthreads, partid=%d, channel=%d\n",
needed, ch->partid, ch->number);
xpc_create_kthreads(ch, needed, 0);
}
void
xpc_activate_partition(struct xpc_partition *part)
{
short partid = XPC_PARTID(part);
unsigned long irq_flags;
struct task_struct *kthread;
spin_lock_irqsave(&part->act_lock, irq_flags);
DBUG_ON(part->act_state != XPC_P_AS_INACTIVE);
part->act_state = XPC_P_AS_ACTIVATION_REQ;
XPC_SET_REASON(part, xpCloneKThread, __LINE__);
spin_unlock_irqrestore(&part->act_lock, irq_flags);
kthread = kthread_run(xpc_activating, (void *)((u64)partid), "xpc%02d",
partid);
if (IS_ERR(kthread)) {
spin_lock_irqsave(&part->act_lock, irq_flags);
part->act_state = XPC_P_AS_INACTIVE;
XPC_SET_REASON(part, xpCloneKThreadFailed, __LINE__);
spin_unlock_irqrestore(&part->act_lock, irq_flags);
}
}
/*
* 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 xp_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_send_chctl_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 xpDisconnecting 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_channel(const int line, struct xpc_channel *ch,
enum xp_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);
ch->flags &= ~(XPC_C_OPENREQUEST | XPC_C_OPENREPLY |
XPC_C_ROPENREQUEST | XPC_C_ROPENREPLY |
XPC_C_CONNECTING | XPC_C_CONNECTED);
xpc_arch_ops.send_chctl_closerequest(ch, irq_flags);
if (channel_was_connected)
ch->flags |= XPC_C_WASCONNECTED;
spin_unlock_irqrestore(&ch->lock, *irq_flags);
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)) {
xpc_create_kthreads(ch, 1, 1);
}
if (atomic_read(&ch->n_on_msg_allocate_wq) > 0)
wake_up(&ch->msg_allocate_wq);
spin_lock_irqsave(&ch->lock, *irq_flags);
}
/*
* 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 xp_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_setup_msg_structures(ch);
spin_lock_irqsave(&ch->lock, *irq_flags);
if (ret != xpSuccess)
XPC_DISCONNECT_CHANNEL(ch, ret, irq_flags);
ch->flags |= XPC_C_SETUP;
if (ch->flags & (XPC_C_CONNECTED | XPC_C_DISCONNECTING))
return;
}
if (!(ch->flags & XPC_C_OPENREPLY)) {
ch->flags |= XPC_C_OPENREPLY;
xpc_send_chctl_openreply(ch, irq_flags);
}
if (!(ch->flags & XPC_C_ROPENREPLY))
return;
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);
}
static enum xp_retval
xpc_save_remote_msgqueue_pa_uv(struct xpc_channel *ch,
unsigned long gru_mq_desc_gpa)
{
struct xpc_channel_uv *ch_uv = &ch->sn.uv;
DBUG_ON(ch_uv->cached_notify_gru_mq_desc == NULL);
return xpc_cache_remote_gru_mq_desc_uv(ch_uv->cached_notify_gru_mq_desc,
gru_mq_desc_gpa);
}
static enum xp_retval
xpc_send_activate_IRQ_uv(struct xpc_partition *part, void *msg, size_t msg_size,
int msg_type)
{
struct xpc_activate_mq_msghdr_uv *msg_hdr = msg;
struct xpc_partition_uv *part_uv = &part->sn.uv;
struct gru_message_queue_desc *gru_mq_desc;
unsigned long irq_flags;
enum xp_retval ret;
DBUG_ON(msg_size > XPC_ACTIVATE_MSG_SIZE_UV);
msg_hdr->type = msg_type;
msg_hdr->partid = xp_partition_id;
msg_hdr->act_state = part->act_state;
msg_hdr->rp_ts_jiffies = xpc_rsvd_page->ts_jiffies;
mutex_lock(&part_uv->cached_activate_gru_mq_desc_mutex);
again:
if (!(part_uv->flags & XPC_P_CACHED_ACTIVATE_GRU_MQ_DESC_UV)) {
gru_mq_desc = part_uv->cached_activate_gru_mq_desc;
if (gru_mq_desc == NULL) {
gru_mq_desc = kmalloc(sizeof(struct
gru_message_queue_desc),
GFP_KERNEL);
if (gru_mq_desc == NULL) {
ret = xpNoMemory;
goto done;
}
part_uv->cached_activate_gru_mq_desc = gru_mq_desc;
}
ret = xpc_cache_remote_gru_mq_desc_uv(gru_mq_desc,
part_uv->
activate_gru_mq_desc_gpa);
if (ret != xpSuccess)
goto done;
spin_lock_irqsave(&part_uv->flags_lock, irq_flags);
part_uv->flags |= XPC_P_CACHED_ACTIVATE_GRU_MQ_DESC_UV;
spin_unlock_irqrestore(&part_uv->flags_lock, irq_flags);
}
/* ??? Is holding a spin_lock (ch->lock) during this call a bad idea? */
ret = xpc_send_gru_msg(part_uv->cached_activate_gru_mq_desc, msg,
msg_size);
if (ret != xpSuccess) {
smp_rmb(); /* ensure a fresh copy of part_uv->flags */
if (!(part_uv->flags & XPC_P_CACHED_ACTIVATE_GRU_MQ_DESC_UV))
goto again;
}
done:
mutex_unlock(&part_uv->cached_activate_gru_mq_desc_mutex);
return ret;
}
/*
* Send a message that contains the user's payload on the specified channel
* connected to the specified partition.
*
* NOTE that this routine can sleep waiting for a message entry to become
* available. To not sleep, pass in the XPC_NOWAIT flag.
*
* Once sent, this routine will not wait for the message to be received, nor
* will notification be given when it does happen.
*
* Arguments:
*
* partid - ID of partition to which the channel is connected.
* ch_number - channel # to send message on.
* flags - see xp.h for valid flags.
* payload - pointer to the payload which is to be sent.
* payload_size - size of the payload in bytes.
*/
enum xp_retval
xpc_initiate_send(short partid, int ch_number, u32 flags, void *payload,
u16 payload_size)
{
struct xpc_partition *part = &xpc_partitions[partid];
enum xp_retval ret = xpUnknownReason;
dev_dbg(xpc_chan, "payload=0x%p, partid=%d, channel=%d\n", payload,
partid, ch_number);
DBUG_ON(partid < 0 || partid >= xp_max_npartitions);
DBUG_ON(ch_number < 0 || ch_number >= part->nchannels);
DBUG_ON(payload == NULL);
if (xpc_part_ref(part)) {
ret = xpc_send_payload(&part->channels[ch_number], flags,
payload, payload_size, 0, NULL, NULL);
xpc_part_deref(part);
}
return ret;
}
enum xp_retval
xpc_connect(int ch_number, xpc_channel_func func, void *key, u16 payload_size,
u16 nentries, u32 assigned_limit, u32 idle_limit)
{
struct xpc_registration *registration;
DBUG_ON(ch_number < 0 || ch_number >= XPC_MAX_NCHANNELS);
DBUG_ON(payload_size == 0 || nentries == 0);
DBUG_ON(func == NULL);
DBUG_ON(assigned_limit == 0 || idle_limit > assigned_limit);
if (XPC_MSG_SIZE(payload_size) > XPC_MSG_MAX_SIZE)
return xpPayloadTooBig;
registration = &xpc_registrations[ch_number];
if (mutex_lock_interruptible(®istration->mutex) != 0)
return xpInterrupted;
if (registration->func != NULL) {
mutex_unlock(®istration->mutex);
return xpAlreadyRegistered;
}
registration->entry_size = XPC_MSG_SIZE(payload_size);
registration->nentries = nentries;
registration->assigned_limit = assigned_limit;
registration->idle_limit = idle_limit;
registration->key = key;
registration->func = func;
mutex_unlock(®istration->mutex);
xpc_interface.connect(ch_number);
return xpSuccess;
}
/*
* Register for automatic establishment of a channel connection whenever
* a partition comes up.
*
* Arguments:
*
* ch_number - channel # to register for connection.
* func - function to call for asynchronous notification of channel
* state changes (i.e., connection, disconnection, error) and
* the arrival of incoming messages.
* key - pointer to optional user-defined value that gets passed back
* to the user on any callouts made to func.
* payload_size - size in bytes of the XPC message's payload area which
* contains a user-defined message. The user should make
* this large enough to hold their largest message.
* nentries - max #of XPC message entries a message queue can contain.
* The actual number, which is determined when a connection
* is established and may be less then requested, will be
* passed to the user via the xpcConnected callout.
* assigned_limit - max number of kthreads allowed to be processing
* messages (per connection) at any given instant.
* idle_limit - max number of kthreads allowed to be idle at any given
* instant.
*/
enum xpc_retval
xpc_connect(int ch_number, xpc_channel_func func, void *key, u16 payload_size,
u16 nentries, u32 assigned_limit, u32 idle_limit)
{
struct xpc_registration *registration;
DBUG_ON(ch_number < 0 || ch_number >= XPC_NCHANNELS);
DBUG_ON(payload_size == 0 || nentries == 0);
DBUG_ON(func == NULL);
DBUG_ON(assigned_limit == 0 || idle_limit > assigned_limit);
registration = &xpc_registrations[ch_number];
if (mutex_lock_interruptible(®istration->mutex) != 0) {
return xpcInterrupted;
}
/* if XPC_CHANNEL_REGISTERED(ch_number) */
if (registration->func != NULL) {
mutex_unlock(®istration->mutex);
return xpcAlreadyRegistered;
}
/* register the channel for connection */
registration->msg_size = XPC_MSG_SIZE(payload_size);
registration->nentries = nentries;
registration->assigned_limit = assigned_limit;
registration->idle_limit = idle_limit;
registration->key = key;
registration->func = func;
mutex_unlock(®istration->mutex);
xpc_interface.connect(ch_number);
return xpcSuccess;
}
void
xpc_disconnect_wait(int ch_number)
{
unsigned long irq_flags;
short partid;
struct xpc_partition *part;
struct xpc_channel *ch;
int wakeup_channel_mgr;
/* now wait for all callouts to the caller's function to cease */
for (partid = 1; partid < XP_MAX_PARTITIONS; partid++) {
part = &xpc_partitions[partid];
if (!xpc_part_ref(part))
continue;
ch = &part->channels[ch_number];
if (!(ch->flags & XPC_C_WDISCONNECT)) {
xpc_part_deref(part);
continue;
}
wait_for_completion(&ch->wdisconnect_wait);
spin_lock_irqsave(&ch->lock, irq_flags);
DBUG_ON(!(ch->flags & XPC_C_DISCONNECTED));
wakeup_channel_mgr = 0;
if (ch->delayed_IPI_flags) {
if (part->act_state != XPC_P_DEACTIVATING) {
spin_lock(&part->IPI_lock);
XPC_SET_IPI_FLAGS(part->local_IPI_amo,
ch->number,
ch->delayed_IPI_flags);
spin_unlock(&part->IPI_lock);
wakeup_channel_mgr = 1;
}
ch->delayed_IPI_flags = 0;
}
ch->flags &= ~XPC_C_WDISCONNECT;
spin_unlock_irqrestore(&ch->lock, irq_flags);
if (wakeup_channel_mgr)
xpc_wakeup_channel_mgr(part);
xpc_part_deref(part);
}
}
static void
xpc_process_activate_IRQ_rcvd_uv(void)
{
unsigned long irq_flags;
short partid;
struct xpc_partition *part;
u8 act_state_req;
DBUG_ON(xpc_activate_IRQ_rcvd == 0);
spin_lock_irqsave(&xpc_activate_IRQ_rcvd_lock, irq_flags);
for (partid = 0; partid < XP_MAX_NPARTITIONS_UV; partid++) {
part = &xpc_partitions[partid];
if (part->sn.uv.act_state_req == 0)
continue;
xpc_activate_IRQ_rcvd--;
BUG_ON(xpc_activate_IRQ_rcvd < 0);
act_state_req = part->sn.uv.act_state_req;
part->sn.uv.act_state_req = 0;
spin_unlock_irqrestore(&xpc_activate_IRQ_rcvd_lock, irq_flags);
if (act_state_req == XPC_P_ASR_ACTIVATE_UV) {
if (part->act_state == XPC_P_AS_INACTIVE)
xpc_activate_partition(part);
else if (part->act_state == XPC_P_AS_DEACTIVATING)
XPC_DEACTIVATE_PARTITION(part, xpReactivating);
} else if (act_state_req == XPC_P_ASR_REACTIVATE_UV) {
if (part->act_state == XPC_P_AS_INACTIVE)
xpc_activate_partition(part);
else
XPC_DEACTIVATE_PARTITION(part, xpReactivating);
} else if (act_state_req == XPC_P_ASR_DEACTIVATE_UV) {
XPC_DEACTIVATE_PARTITION(part, part->sn.uv.reason);
} else {
BUG();
}
spin_lock_irqsave(&xpc_activate_IRQ_rcvd_lock, irq_flags);
if (xpc_activate_IRQ_rcvd == 0)
break;
}
spin_unlock_irqrestore(&xpc_activate_IRQ_rcvd_lock, irq_flags);
}
void
xpc_disconnect_wait(int ch_number)
{
unsigned long irq_flags;
short partid;
struct xpc_partition *part;
struct xpc_channel *ch;
int wakeup_channel_mgr;
/* */
for (partid = 0; partid < xp_max_npartitions; partid++) {
part = &xpc_partitions[partid];
if (!xpc_part_ref(part))
continue;
ch = &part->channels[ch_number];
if (!(ch->flags & XPC_C_WDISCONNECT)) {
xpc_part_deref(part);
continue;
}
wait_for_completion(&ch->wdisconnect_wait);
spin_lock_irqsave(&ch->lock, irq_flags);
DBUG_ON(!(ch->flags & XPC_C_DISCONNECTED));
wakeup_channel_mgr = 0;
if (ch->delayed_chctl_flags) {
if (part->act_state != XPC_P_AS_DEACTIVATING) {
spin_lock(&part->chctl_lock);
part->chctl.flags[ch->number] |=
ch->delayed_chctl_flags;
spin_unlock(&part->chctl_lock);
wakeup_channel_mgr = 1;
}
ch->delayed_chctl_flags = 0;
}
ch->flags &= ~XPC_C_WDISCONNECT;
spin_unlock_irqrestore(&ch->lock, irq_flags);
if (wakeup_channel_mgr)
xpc_wakeup_channel_mgr(part);
xpc_part_deref(part);
}
}
void
xpc_process_sent_chctl_flags(struct xpc_partition *part)
{
unsigned long irq_flags;
union xpc_channel_ctl_flags chctl;
struct xpc_channel *ch;
int ch_number;
u32 ch_flags;
chctl.all_flags = xpc_arch_ops.get_chctl_all_flags(part);
for (ch_number = 0; ch_number < part->nchannels; ch_number++) {
ch = &part->channels[ch_number];
if (chctl.flags[ch_number] & XPC_OPENCLOSE_CHCTL_FLAGS) {
xpc_process_openclose_chctl_flags(part, ch_number,
chctl.flags[ch_number]);
}
ch_flags = ch->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_AS_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);
}
continue;
}
if (chctl.flags[ch_number] & XPC_MSG_CHCTL_FLAGS)
xpc_arch_ops.process_msg_chctl_flags(part, ch_number);
}
}
/*
* Handle the receipt of a SGI_XPC_NOTIFY IRQ by seeing whether the specified
* partition actually sent it. Since SGI_XPC_NOTIFY IRQs may be shared by more
* than one partition, we use an AMO_t structure per partition to indicate
* whether a partition has sent an IPI or not. If it has, then wake up the
* associated kthread to handle it.
*
* All SGI_XPC_NOTIFY IRQs received by XPC are the result of IPIs sent by XPC
* running on other partitions.
*
* Noteworthy Arguments:
*
* irq - Interrupt ReQuest number. NOT USED.
*
* dev_id - partid of IPI's potential sender.
*/
irqreturn_t
xpc_notify_IRQ_handler(int irq, void *dev_id)
{
short partid = (short)(u64)dev_id;
struct xpc_partition *part = &xpc_partitions[partid];
DBUG_ON(partid <= 0 || partid >= XP_MAX_PARTITIONS);
if (xpc_part_ref(part)) {
xpc_check_for_channel_activity(part);
xpc_part_deref(part);
}
return IRQ_HANDLED;
}
/*
* Free up msg_slots and clear other stuff that were setup for the specified
* channel.
*/
static void
xpc_teardown_msg_structures_uv(struct xpc_channel *ch)
{
struct xpc_channel_uv *ch_uv = &ch->sn.uv;
DBUG_ON(!spin_is_locked(&ch->lock));
kfree(ch_uv->cached_notify_gru_mq_desc);
ch_uv->cached_notify_gru_mq_desc = NULL;
if (ch->flags & XPC_C_SETUP) {
xpc_init_fifo_uv(&ch_uv->msg_slot_free_list);
kfree(ch_uv->send_msg_slots);
xpc_init_fifo_uv(&ch_uv->recv_msg_list);
kfree(ch_uv->recv_msg_slots);
}
}
/*
* Tell the callers of xpc_send_notify() that the status of their payloads
* is unknown because the channel is now disconnecting.
*
* We don't worry about putting these msg_slots on the free list since the
* msg_slots themselves are about to be kfree'd.
*/
static void
xpc_notify_senders_of_disconnect_uv(struct xpc_channel *ch)
{
struct xpc_send_msg_slot_uv *msg_slot;
int entry;
DBUG_ON(!(ch->flags & XPC_C_DISCONNECTING));
for (entry = 0; entry < ch->local_nentries; entry++) {
if (atomic_read(&ch->n_to_notify) == 0)
break;
msg_slot = &ch->sn.uv.send_msg_slots[entry];
if (msg_slot->func != NULL)
xpc_notify_sender_uv(ch, msg_slot, ch->reason);
}
}
