2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
6 * Copyright (c) 2004-2009 Silicon Graphics, Inc. All Rights Reserved.
10 * Cross Partition Communication (XPC) channel support.
12 * This is the part of XPC that manages the channels and
13 * sends/receives messages across them to/from other partitions.
17 #include <linux/device.h>
21 * Process a connect message from a remote partition.
23 * Note: xpc_process_connect() is expecting to be called with the
24 * spin_lock_irqsave held and will leave it locked upon return.
27 xpc_process_connect(struct xpc_channel
*ch
, unsigned long *irq_flags
)
31 DBUG_ON(!spin_is_locked(&ch
->lock
));
33 if (!(ch
->flags
& XPC_C_OPENREQUEST
) ||
34 !(ch
->flags
& XPC_C_ROPENREQUEST
)) {
35 /* nothing more to do for now */
38 DBUG_ON(!(ch
->flags
& XPC_C_CONNECTING
));
40 if (!(ch
->flags
& XPC_C_SETUP
)) {
41 spin_unlock_irqrestore(&ch
->lock
, *irq_flags
);
42 ret
= xpc_arch_ops
.setup_msg_structures(ch
);
43 spin_lock_irqsave(&ch
->lock
, *irq_flags
);
46 XPC_DISCONNECT_CHANNEL(ch
, ret
, irq_flags
);
48 ch
->flags
|= XPC_C_SETUP
;
50 if (ch
->flags
& XPC_C_DISCONNECTING
)
54 if (!(ch
->flags
& XPC_C_OPENREPLY
)) {
55 ch
->flags
|= XPC_C_OPENREPLY
;
56 xpc_arch_ops
.send_chctl_openreply(ch
, irq_flags
);
59 if (!(ch
->flags
& XPC_C_ROPENREPLY
))
62 if (!(ch
->flags
& XPC_C_OPENCOMPLETE
)) {
63 ch
->flags
|= (XPC_C_OPENCOMPLETE
| XPC_C_CONNECTED
);
64 xpc_arch_ops
.send_chctl_opencomplete(ch
, irq_flags
);
67 if (!(ch
->flags
& XPC_C_ROPENCOMPLETE
))
70 dev_info(xpc_chan
, "channel %d to partition %d connected\n",
71 ch
->number
, ch
->partid
);
73 ch
->flags
= (XPC_C_CONNECTED
| XPC_C_SETUP
); /* clear all else */
77 * spin_lock_irqsave() is expected to be held on entry.
80 xpc_process_disconnect(struct xpc_channel
*ch
, unsigned long *irq_flags
)
82 struct xpc_partition
*part
= &xpc_partitions
[ch
->partid
];
83 u32 channel_was_connected
= (ch
->flags
& XPC_C_WASCONNECTED
);
85 DBUG_ON(!spin_is_locked(&ch
->lock
));
87 if (!(ch
->flags
& XPC_C_DISCONNECTING
))
90 DBUG_ON(!(ch
->flags
& XPC_C_CLOSEREQUEST
));
92 /* make sure all activity has settled down first */
94 if (atomic_read(&ch
->kthreads_assigned
) > 0 ||
95 atomic_read(&ch
->references
) > 0) {
98 DBUG_ON((ch
->flags
& XPC_C_CONNECTEDCALLOUT_MADE
) &&
99 !(ch
->flags
& XPC_C_DISCONNECTINGCALLOUT_MADE
));
101 if (part
->act_state
== XPC_P_AS_DEACTIVATING
) {
102 /* can't proceed until the other side disengages from us */
103 if (xpc_arch_ops
.partition_engaged(ch
->partid
))
108 /* as long as the other side is up do the full protocol */
110 if (!(ch
->flags
& XPC_C_RCLOSEREQUEST
))
113 if (!(ch
->flags
& XPC_C_CLOSEREPLY
)) {
114 ch
->flags
|= XPC_C_CLOSEREPLY
;
115 xpc_arch_ops
.send_chctl_closereply(ch
, irq_flags
);
118 if (!(ch
->flags
& XPC_C_RCLOSEREPLY
))
122 /* wake those waiting for notify completion */
123 if (atomic_read(&ch
->n_to_notify
) > 0) {
124 /* we do callout while holding ch->lock, callout can't block */
125 xpc_arch_ops
.notify_senders_of_disconnect(ch
);
128 /* both sides are disconnected now */
130 if (ch
->flags
& XPC_C_DISCONNECTINGCALLOUT_MADE
) {
131 spin_unlock_irqrestore(&ch
->lock
, *irq_flags
);
132 xpc_disconnect_callout(ch
, xpDisconnected
);
133 spin_lock_irqsave(&ch
->lock
, *irq_flags
);
136 DBUG_ON(atomic_read(&ch
->n_to_notify
) != 0);
138 /* it's now safe to free the channel's message queues */
139 xpc_arch_ops
.teardown_msg_structures(ch
);
144 ch
->local_nentries
= 0;
145 ch
->remote_nentries
= 0;
146 ch
->kthreads_assigned_limit
= 0;
147 ch
->kthreads_idle_limit
= 0;
150 * Mark the channel disconnected and clear all other flags, including
151 * XPC_C_SETUP (because of call to
152 * xpc_arch_ops.teardown_msg_structures()) but not including
153 * XPC_C_WDISCONNECT (if it was set).
155 ch
->flags
= (XPC_C_DISCONNECTED
| (ch
->flags
& XPC_C_WDISCONNECT
));
157 atomic_dec(&part
->nchannels_active
);
159 if (channel_was_connected
) {
160 dev_info(xpc_chan
, "channel %d to partition %d disconnected, "
161 "reason=%d\n", ch
->number
, ch
->partid
, ch
->reason
);
164 if (ch
->flags
& XPC_C_WDISCONNECT
) {
165 /* we won't lose the CPU since we're holding ch->lock */
166 complete(&ch
->wdisconnect_wait
);
167 } else if (ch
->delayed_chctl_flags
) {
168 if (part
->act_state
!= XPC_P_AS_DEACTIVATING
) {
169 /* time to take action on any delayed chctl flags */
170 spin_lock(&part
->chctl_lock
);
171 part
->chctl
.flags
[ch
->number
] |=
172 ch
->delayed_chctl_flags
;
173 spin_unlock(&part
->chctl_lock
);
175 ch
->delayed_chctl_flags
= 0;
180 * Process a change in the channel's remote connection state.
183 xpc_process_openclose_chctl_flags(struct xpc_partition
*part
, int ch_number
,
186 unsigned long irq_flags
;
187 struct xpc_openclose_args
*args
=
188 &part
->remote_openclose_args
[ch_number
];
189 struct xpc_channel
*ch
= &part
->channels
[ch_number
];
190 enum xp_retval reason
;
192 int create_kthread
= 0;
194 spin_lock_irqsave(&ch
->lock
, irq_flags
);
198 if ((ch
->flags
& XPC_C_DISCONNECTED
) &&
199 (ch
->flags
& XPC_C_WDISCONNECT
)) {
201 * Delay processing chctl flags until thread waiting disconnect
202 * has had a chance to see that the channel is disconnected.
204 ch
->delayed_chctl_flags
|= chctl_flags
;
208 if (chctl_flags
& XPC_CHCTL_CLOSEREQUEST
) {
210 dev_dbg(xpc_chan
, "XPC_CHCTL_CLOSEREQUEST (reason=%d) received "
211 "from partid=%d, channel=%d\n", args
->reason
,
212 ch
->partid
, ch
->number
);
215 * If RCLOSEREQUEST is set, we're probably waiting for
216 * RCLOSEREPLY. We should find it and a ROPENREQUEST packed
217 * with this RCLOSEREQUEST in the chctl_flags.
220 if (ch
->flags
& XPC_C_RCLOSEREQUEST
) {
221 DBUG_ON(!(ch
->flags
& XPC_C_DISCONNECTING
));
222 DBUG_ON(!(ch
->flags
& XPC_C_CLOSEREQUEST
));
223 DBUG_ON(!(ch
->flags
& XPC_C_CLOSEREPLY
));
224 DBUG_ON(ch
->flags
& XPC_C_RCLOSEREPLY
);
226 DBUG_ON(!(chctl_flags
& XPC_CHCTL_CLOSEREPLY
));
227 chctl_flags
&= ~XPC_CHCTL_CLOSEREPLY
;
228 ch
->flags
|= XPC_C_RCLOSEREPLY
;
230 /* both sides have finished disconnecting */
231 xpc_process_disconnect(ch
, &irq_flags
);
232 DBUG_ON(!(ch
->flags
& XPC_C_DISCONNECTED
));
236 if (ch
->flags
& XPC_C_DISCONNECTED
) {
237 if (!(chctl_flags
& XPC_CHCTL_OPENREQUEST
)) {
238 if (part
->chctl
.flags
[ch_number
] &
239 XPC_CHCTL_OPENREQUEST
) {
241 DBUG_ON(ch
->delayed_chctl_flags
!= 0);
242 spin_lock(&part
->chctl_lock
);
243 part
->chctl
.flags
[ch_number
] |=
244 XPC_CHCTL_CLOSEREQUEST
;
245 spin_unlock(&part
->chctl_lock
);
250 XPC_SET_REASON(ch
, 0, 0);
251 ch
->flags
&= ~XPC_C_DISCONNECTED
;
253 atomic_inc(&part
->nchannels_active
);
254 ch
->flags
|= (XPC_C_CONNECTING
| XPC_C_ROPENREQUEST
);
257 chctl_flags
&= ~(XPC_CHCTL_OPENREQUEST
| XPC_CHCTL_OPENREPLY
|
258 XPC_CHCTL_OPENCOMPLETE
);
261 * The meaningful CLOSEREQUEST connection state fields are:
262 * reason = reason connection is to be closed
265 ch
->flags
|= XPC_C_RCLOSEREQUEST
;
267 if (!(ch
->flags
& XPC_C_DISCONNECTING
)) {
268 reason
= args
->reason
;
269 if (reason
<= xpSuccess
|| reason
> xpUnknownReason
)
270 reason
= xpUnknownReason
;
271 else if (reason
== xpUnregistering
)
272 reason
= xpOtherUnregistering
;
274 XPC_DISCONNECT_CHANNEL(ch
, reason
, &irq_flags
);
276 DBUG_ON(chctl_flags
& XPC_CHCTL_CLOSEREPLY
);
280 xpc_process_disconnect(ch
, &irq_flags
);
283 if (chctl_flags
& XPC_CHCTL_CLOSEREPLY
) {
285 dev_dbg(xpc_chan
, "XPC_CHCTL_CLOSEREPLY received from partid="
286 "%d, channel=%d\n", ch
->partid
, ch
->number
);
288 if (ch
->flags
& XPC_C_DISCONNECTED
) {
289 DBUG_ON(part
->act_state
!= XPC_P_AS_DEACTIVATING
);
293 DBUG_ON(!(ch
->flags
& XPC_C_CLOSEREQUEST
));
295 if (!(ch
->flags
& XPC_C_RCLOSEREQUEST
)) {
296 if (part
->chctl
.flags
[ch_number
] &
297 XPC_CHCTL_CLOSEREQUEST
) {
299 DBUG_ON(ch
->delayed_chctl_flags
!= 0);
300 spin_lock(&part
->chctl_lock
);
301 part
->chctl
.flags
[ch_number
] |=
302 XPC_CHCTL_CLOSEREPLY
;
303 spin_unlock(&part
->chctl_lock
);
308 ch
->flags
|= XPC_C_RCLOSEREPLY
;
310 if (ch
->flags
& XPC_C_CLOSEREPLY
) {
311 /* both sides have finished disconnecting */
312 xpc_process_disconnect(ch
, &irq_flags
);
316 if (chctl_flags
& XPC_CHCTL_OPENREQUEST
) {
318 dev_dbg(xpc_chan
, "XPC_CHCTL_OPENREQUEST (entry_size=%d, "
319 "local_nentries=%d) received from partid=%d, "
320 "channel=%d\n", args
->entry_size
, args
->local_nentries
,
321 ch
->partid
, ch
->number
);
323 if (part
->act_state
== XPC_P_AS_DEACTIVATING
||
324 (ch
->flags
& XPC_C_ROPENREQUEST
)) {
328 if (ch
->flags
& (XPC_C_DISCONNECTING
| XPC_C_WDISCONNECT
)) {
329 ch
->delayed_chctl_flags
|= XPC_CHCTL_OPENREQUEST
;
332 DBUG_ON(!(ch
->flags
& (XPC_C_DISCONNECTED
|
333 XPC_C_OPENREQUEST
)));
334 DBUG_ON(ch
->flags
& (XPC_C_ROPENREQUEST
| XPC_C_ROPENREPLY
|
335 XPC_C_OPENREPLY
| XPC_C_CONNECTED
));
338 * The meaningful OPENREQUEST connection state fields are:
339 * entry_size = size of channel's messages in bytes
340 * local_nentries = remote partition's local_nentries
342 if (args
->entry_size
== 0 || args
->local_nentries
== 0) {
343 /* assume OPENREQUEST was delayed by mistake */
347 ch
->flags
|= (XPC_C_ROPENREQUEST
| XPC_C_CONNECTING
);
348 ch
->remote_nentries
= args
->local_nentries
;
350 if (ch
->flags
& XPC_C_OPENREQUEST
) {
351 if (args
->entry_size
!= ch
->entry_size
) {
352 XPC_DISCONNECT_CHANNEL(ch
, xpUnequalMsgSizes
,
357 ch
->entry_size
= args
->entry_size
;
359 XPC_SET_REASON(ch
, 0, 0);
360 ch
->flags
&= ~XPC_C_DISCONNECTED
;
362 atomic_inc(&part
->nchannels_active
);
365 xpc_process_connect(ch
, &irq_flags
);
368 if (chctl_flags
& XPC_CHCTL_OPENREPLY
) {
370 dev_dbg(xpc_chan
, "XPC_CHCTL_OPENREPLY (local_msgqueue_pa="
371 "0x%lx, local_nentries=%d, remote_nentries=%d) "
372 "received from partid=%d, channel=%d\n",
373 args
->local_msgqueue_pa
, args
->local_nentries
,
374 args
->remote_nentries
, ch
->partid
, ch
->number
);
376 if (ch
->flags
& (XPC_C_DISCONNECTING
| XPC_C_DISCONNECTED
))
379 if (!(ch
->flags
& XPC_C_OPENREQUEST
)) {
380 XPC_DISCONNECT_CHANNEL(ch
, xpOpenCloseError
,
385 DBUG_ON(!(ch
->flags
& XPC_C_ROPENREQUEST
));
386 DBUG_ON(ch
->flags
& XPC_C_CONNECTED
);
389 * The meaningful OPENREPLY connection state fields are:
390 * local_msgqueue_pa = physical address of remote
391 * partition's local_msgqueue
392 * local_nentries = remote partition's local_nentries
393 * remote_nentries = remote partition's remote_nentries
395 DBUG_ON(args
->local_msgqueue_pa
== 0);
396 DBUG_ON(args
->local_nentries
== 0);
397 DBUG_ON(args
->remote_nentries
== 0);
399 ret
= xpc_arch_ops
.save_remote_msgqueue_pa(ch
,
400 args
->local_msgqueue_pa
);
401 if (ret
!= xpSuccess
) {
402 XPC_DISCONNECT_CHANNEL(ch
, ret
, &irq_flags
);
405 ch
->flags
|= XPC_C_ROPENREPLY
;
407 if (args
->local_nentries
< ch
->remote_nentries
) {
408 dev_dbg(xpc_chan
, "XPC_CHCTL_OPENREPLY: new "
409 "remote_nentries=%d, old remote_nentries=%d, "
410 "partid=%d, channel=%d\n",
411 args
->local_nentries
, ch
->remote_nentries
,
412 ch
->partid
, ch
->number
);
414 ch
->remote_nentries
= args
->local_nentries
;
416 if (args
->remote_nentries
< ch
->local_nentries
) {
417 dev_dbg(xpc_chan
, "XPC_CHCTL_OPENREPLY: new "
418 "local_nentries=%d, old local_nentries=%d, "
419 "partid=%d, channel=%d\n",
420 args
->remote_nentries
, ch
->local_nentries
,
421 ch
->partid
, ch
->number
);
423 ch
->local_nentries
= args
->remote_nentries
;
426 xpc_process_connect(ch
, &irq_flags
);
429 if (chctl_flags
& XPC_CHCTL_OPENCOMPLETE
) {
431 dev_dbg(xpc_chan
, "XPC_CHCTL_OPENCOMPLETE received from "
432 "partid=%d, channel=%d\n", ch
->partid
, ch
->number
);
434 if (ch
->flags
& (XPC_C_DISCONNECTING
| XPC_C_DISCONNECTED
))
437 if (!(ch
->flags
& XPC_C_OPENREQUEST
) ||
438 !(ch
->flags
& XPC_C_OPENREPLY
)) {
439 XPC_DISCONNECT_CHANNEL(ch
, xpOpenCloseError
,
444 DBUG_ON(!(ch
->flags
& XPC_C_ROPENREQUEST
));
445 DBUG_ON(!(ch
->flags
& XPC_C_ROPENREPLY
));
446 DBUG_ON(!(ch
->flags
& XPC_C_CONNECTED
));
448 ch
->flags
|= XPC_C_ROPENCOMPLETE
;
450 xpc_process_connect(ch
, &irq_flags
);
455 spin_unlock_irqrestore(&ch
->lock
, irq_flags
);
458 xpc_create_kthreads(ch
, 1, 0);
462 * Attempt to establish a channel connection to a remote partition.
464 static enum xp_retval
465 xpc_connect_channel(struct xpc_channel
*ch
)
467 unsigned long irq_flags
;
468 struct xpc_registration
*registration
= &xpc_registrations
[ch
->number
];
470 if (mutex_trylock(®istration
->mutex
) == 0)
473 if (!XPC_CHANNEL_REGISTERED(ch
->number
)) {
474 mutex_unlock(®istration
->mutex
);
475 return xpUnregistered
;
478 spin_lock_irqsave(&ch
->lock
, irq_flags
);
480 DBUG_ON(ch
->flags
& XPC_C_CONNECTED
);
481 DBUG_ON(ch
->flags
& XPC_C_OPENREQUEST
);
483 if (ch
->flags
& XPC_C_DISCONNECTING
) {
484 spin_unlock_irqrestore(&ch
->lock
, irq_flags
);
485 mutex_unlock(®istration
->mutex
);
489 /* add info from the channel connect registration to the channel */
491 ch
->kthreads_assigned_limit
= registration
->assigned_limit
;
492 ch
->kthreads_idle_limit
= registration
->idle_limit
;
493 DBUG_ON(atomic_read(&ch
->kthreads_assigned
) != 0);
494 DBUG_ON(atomic_read(&ch
->kthreads_idle
) != 0);
495 DBUG_ON(atomic_read(&ch
->kthreads_active
) != 0);
497 ch
->func
= registration
->func
;
498 DBUG_ON(registration
->func
== NULL
);
499 ch
->key
= registration
->key
;
501 ch
->local_nentries
= registration
->nentries
;
503 if (ch
->flags
& XPC_C_ROPENREQUEST
) {
504 if (registration
->entry_size
!= ch
->entry_size
) {
505 /* the local and remote sides aren't the same */
508 * Because XPC_DISCONNECT_CHANNEL() can block we're
509 * forced to up the registration sema before we unlock
510 * the channel lock. But that's okay here because we're
511 * done with the part that required the registration
512 * sema. XPC_DISCONNECT_CHANNEL() requires that the
513 * channel lock be locked and will unlock and relock
514 * the channel lock as needed.
516 mutex_unlock(®istration
->mutex
);
517 XPC_DISCONNECT_CHANNEL(ch
, xpUnequalMsgSizes
,
519 spin_unlock_irqrestore(&ch
->lock
, irq_flags
);
520 return xpUnequalMsgSizes
;
523 ch
->entry_size
= registration
->entry_size
;
525 XPC_SET_REASON(ch
, 0, 0);
526 ch
->flags
&= ~XPC_C_DISCONNECTED
;
528 atomic_inc(&xpc_partitions
[ch
->partid
].nchannels_active
);
531 mutex_unlock(®istration
->mutex
);
533 /* initiate the connection */
535 ch
->flags
|= (XPC_C_OPENREQUEST
| XPC_C_CONNECTING
);
536 xpc_arch_ops
.send_chctl_openrequest(ch
, &irq_flags
);
538 xpc_process_connect(ch
, &irq_flags
);
540 spin_unlock_irqrestore(&ch
->lock
, irq_flags
);
546 xpc_process_sent_chctl_flags(struct xpc_partition
*part
)
548 unsigned long irq_flags
;
549 union xpc_channel_ctl_flags chctl
;
550 struct xpc_channel
*ch
;
554 chctl
.all_flags
= xpc_arch_ops
.get_chctl_all_flags(part
);
557 * Initiate channel connections for registered channels.
559 * For each connected channel that has pending messages activate idle
560 * kthreads and/or create new kthreads as needed.
563 for (ch_number
= 0; ch_number
< part
->nchannels
; ch_number
++) {
564 ch
= &part
->channels
[ch_number
];
567 * Process any open or close related chctl flags, and then deal
568 * with connecting or disconnecting the channel as required.
571 if (chctl
.flags
[ch_number
] & XPC_OPENCLOSE_CHCTL_FLAGS
) {
572 xpc_process_openclose_chctl_flags(part
, ch_number
,
573 chctl
.flags
[ch_number
]);
576 ch_flags
= ch
->flags
; /* need an atomic snapshot of flags */
578 if (ch_flags
& XPC_C_DISCONNECTING
) {
579 spin_lock_irqsave(&ch
->lock
, irq_flags
);
580 xpc_process_disconnect(ch
, &irq_flags
);
581 spin_unlock_irqrestore(&ch
->lock
, irq_flags
);
585 if (part
->act_state
== XPC_P_AS_DEACTIVATING
)
588 if (!(ch_flags
& XPC_C_CONNECTED
)) {
589 if (!(ch_flags
& XPC_C_OPENREQUEST
)) {
590 DBUG_ON(ch_flags
& XPC_C_SETUP
);
591 (void)xpc_connect_channel(ch
);
597 * Process any message related chctl flags, this may involve
598 * the activation of kthreads to deliver any pending messages
599 * sent from the other partition.
602 if (chctl
.flags
[ch_number
] & XPC_MSG_CHCTL_FLAGS
)
603 xpc_arch_ops
.process_msg_chctl_flags(part
, ch_number
);
608 * XPC's heartbeat code calls this function to inform XPC that a partition is
609 * going down. XPC responds by tearing down the XPartition Communication
610 * infrastructure used for the just downed partition.
612 * XPC's heartbeat code will never call this function and xpc_partition_up()
613 * at the same time. Nor will it ever make multiple calls to either function
617 xpc_partition_going_down(struct xpc_partition
*part
, enum xp_retval reason
)
619 unsigned long irq_flags
;
621 struct xpc_channel
*ch
;
623 dev_dbg(xpc_chan
, "deactivating partition %d, reason=%d\n",
624 XPC_PARTID(part
), reason
);
626 if (!xpc_part_ref(part
)) {
627 /* infrastructure for this partition isn't currently set up */
631 /* disconnect channels associated with the partition going down */
633 for (ch_number
= 0; ch_number
< part
->nchannels
; ch_number
++) {
634 ch
= &part
->channels
[ch_number
];
636 xpc_msgqueue_ref(ch
);
637 spin_lock_irqsave(&ch
->lock
, irq_flags
);
639 XPC_DISCONNECT_CHANNEL(ch
, reason
, &irq_flags
);
641 spin_unlock_irqrestore(&ch
->lock
, irq_flags
);
642 xpc_msgqueue_deref(ch
);
645 xpc_wakeup_channel_mgr(part
);
647 xpc_part_deref(part
);
651 * Called by XP at the time of channel connection registration to cause
652 * XPC to establish connections to all currently active partitions.
655 xpc_initiate_connect(int ch_number
)
658 struct xpc_partition
*part
;
659 struct xpc_channel
*ch
;
661 DBUG_ON(ch_number
< 0 || ch_number
>= XPC_MAX_NCHANNELS
);
663 for (partid
= 0; partid
< xp_max_npartitions
; partid
++) {
664 part
= &xpc_partitions
[partid
];
666 if (xpc_part_ref(part
)) {
667 ch
= &part
->channels
[ch_number
];
670 * Initiate the establishment of a connection on the
671 * newly registered channel to the remote partition.
673 xpc_wakeup_channel_mgr(part
);
674 xpc_part_deref(part
);
680 xpc_connected_callout(struct xpc_channel
*ch
)
682 /* let the registerer know that a connection has been established */
684 if (ch
->func
!= NULL
) {
685 dev_dbg(xpc_chan
, "ch->func() called, reason=xpConnected, "
686 "partid=%d, channel=%d\n", ch
->partid
, ch
->number
);
688 ch
->func(xpConnected
, ch
->partid
, ch
->number
,
689 (void *)(u64
)ch
->local_nentries
, ch
->key
);
691 dev_dbg(xpc_chan
, "ch->func() returned, reason=xpConnected, "
692 "partid=%d, channel=%d\n", ch
->partid
, ch
->number
);
697 * Called by XP at the time of channel connection unregistration to cause
698 * XPC to teardown all current connections for the specified channel.
700 * Before returning xpc_initiate_disconnect() will wait until all connections
701 * on the specified channel have been closed/torndown. So the caller can be
702 * assured that they will not be receiving any more callouts from XPC to the
703 * function they registered via xpc_connect().
707 * ch_number - channel # to unregister.
710 xpc_initiate_disconnect(int ch_number
)
712 unsigned long irq_flags
;
714 struct xpc_partition
*part
;
715 struct xpc_channel
*ch
;
717 DBUG_ON(ch_number
< 0 || ch_number
>= XPC_MAX_NCHANNELS
);
719 /* initiate the channel disconnect for every active partition */
720 for (partid
= 0; partid
< xp_max_npartitions
; partid
++) {
721 part
= &xpc_partitions
[partid
];
723 if (xpc_part_ref(part
)) {
724 ch
= &part
->channels
[ch_number
];
725 xpc_msgqueue_ref(ch
);
727 spin_lock_irqsave(&ch
->lock
, irq_flags
);
729 if (!(ch
->flags
& XPC_C_DISCONNECTED
)) {
730 ch
->flags
|= XPC_C_WDISCONNECT
;
732 XPC_DISCONNECT_CHANNEL(ch
, xpUnregistering
,
736 spin_unlock_irqrestore(&ch
->lock
, irq_flags
);
738 xpc_msgqueue_deref(ch
);
739 xpc_part_deref(part
);
743 xpc_disconnect_wait(ch_number
);
747 * To disconnect a channel, and reflect it back to all who may be waiting.
749 * An OPEN is not allowed until XPC_C_DISCONNECTING is cleared by
750 * xpc_process_disconnect(), and if set, XPC_C_WDISCONNECT is cleared by
751 * xpc_disconnect_wait().
753 * THE CHANNEL IS TO BE LOCKED BY THE CALLER AND WILL REMAIN LOCKED UPON RETURN.
756 xpc_disconnect_channel(const int line
, struct xpc_channel
*ch
,
757 enum xp_retval reason
, unsigned long *irq_flags
)
759 u32 channel_was_connected
= (ch
->flags
& XPC_C_CONNECTED
);
761 DBUG_ON(!spin_is_locked(&ch
->lock
));
763 if (ch
->flags
& (XPC_C_DISCONNECTING
| XPC_C_DISCONNECTED
))
766 DBUG_ON(!(ch
->flags
& (XPC_C_CONNECTING
| XPC_C_CONNECTED
)));
768 dev_dbg(xpc_chan
, "reason=%d, line=%d, partid=%d, channel=%d\n",
769 reason
, line
, ch
->partid
, ch
->number
);
771 XPC_SET_REASON(ch
, reason
, line
);
773 ch
->flags
|= (XPC_C_CLOSEREQUEST
| XPC_C_DISCONNECTING
);
774 /* some of these may not have been set */
775 ch
->flags
&= ~(XPC_C_OPENREQUEST
| XPC_C_OPENREPLY
|
776 XPC_C_ROPENREQUEST
| XPC_C_ROPENREPLY
|
777 XPC_C_CONNECTING
| XPC_C_CONNECTED
);
779 xpc_arch_ops
.send_chctl_closerequest(ch
, irq_flags
);
781 if (channel_was_connected
)
782 ch
->flags
|= XPC_C_WASCONNECTED
;
784 spin_unlock_irqrestore(&ch
->lock
, *irq_flags
);
786 /* wake all idle kthreads so they can exit */
787 if (atomic_read(&ch
->kthreads_idle
) > 0) {
788 wake_up_all(&ch
->idle_wq
);
790 } else if ((ch
->flags
& XPC_C_CONNECTEDCALLOUT_MADE
) &&
791 !(ch
->flags
& XPC_C_DISCONNECTINGCALLOUT
)) {
792 /* start a kthread that will do the xpDisconnecting callout */
793 xpc_create_kthreads(ch
, 1, 1);
796 /* wake those waiting to allocate an entry from the local msg queue */
797 if (atomic_read(&ch
->n_on_msg_allocate_wq
) > 0)
798 wake_up(&ch
->msg_allocate_wq
);
800 spin_lock_irqsave(&ch
->lock
, *irq_flags
);
804 xpc_disconnect_callout(struct xpc_channel
*ch
, enum xp_retval reason
)
807 * Let the channel's registerer know that the channel is being
808 * disconnected. We don't want to do this if the registerer was never
809 * informed of a connection being made.
812 if (ch
->func
!= NULL
) {
813 dev_dbg(xpc_chan
, "ch->func() called, reason=%d, partid=%d, "
814 "channel=%d\n", reason
, ch
->partid
, ch
->number
);
816 ch
->func(reason
, ch
->partid
, ch
->number
, NULL
, ch
->key
);
818 dev_dbg(xpc_chan
, "ch->func() returned, reason=%d, partid=%d, "
819 "channel=%d\n", reason
, ch
->partid
, ch
->number
);
824 * Wait for a message entry to become available for the specified channel,
825 * but don't wait any longer than 1 jiffy.
828 xpc_allocate_msg_wait(struct xpc_channel
*ch
)
832 if (ch
->flags
& XPC_C_DISCONNECTING
) {
833 DBUG_ON(ch
->reason
== xpInterrupted
);
837 atomic_inc(&ch
->n_on_msg_allocate_wq
);
838 ret
= interruptible_sleep_on_timeout(&ch
->msg_allocate_wq
, 1);
839 atomic_dec(&ch
->n_on_msg_allocate_wq
);
841 if (ch
->flags
& XPC_C_DISCONNECTING
) {
843 DBUG_ON(ch
->reason
== xpInterrupted
);
844 } else if (ret
== 0) {
854 * Send a message that contains the user's payload on the specified channel
855 * connected to the specified partition.
857 * NOTE that this routine can sleep waiting for a message entry to become
858 * available. To not sleep, pass in the XPC_NOWAIT flag.
860 * Once sent, this routine will not wait for the message to be received, nor
861 * will notification be given when it does happen.
865 * partid - ID of partition to which the channel is connected.
866 * ch_number - channel # to send message on.
867 * flags - see xp.h for valid flags.
868 * payload - pointer to the payload which is to be sent.
869 * payload_size - size of the payload in bytes.
872 xpc_initiate_send(short partid
, int ch_number
, u32 flags
, void *payload
,
875 struct xpc_partition
*part
= &xpc_partitions
[partid
];
876 enum xp_retval ret
= xpUnknownReason
;
878 dev_dbg(xpc_chan
, "payload=0x%p, partid=%d, channel=%d\n", payload
,
881 DBUG_ON(partid
< 0 || partid
>= xp_max_npartitions
);
882 DBUG_ON(ch_number
< 0 || ch_number
>= part
->nchannels
);
883 DBUG_ON(payload
== NULL
);
885 if (xpc_part_ref(part
)) {
886 ret
= xpc_arch_ops
.send_payload(&part
->channels
[ch_number
],
887 flags
, payload
, payload_size
, 0, NULL
, NULL
);
888 xpc_part_deref(part
);
895 * Send a message that contains the user's payload on the specified channel
896 * connected to the specified partition.
898 * NOTE that this routine can sleep waiting for a message entry to become
899 * available. To not sleep, pass in the XPC_NOWAIT flag.
901 * This routine will not wait for the message to be sent or received.
903 * Once the remote end of the channel has received the message, the function
904 * passed as an argument to xpc_initiate_send_notify() will be called. This
905 * allows the sender to free up or re-use any buffers referenced by the
906 * message, but does NOT mean the message has been processed at the remote
909 * If this routine returns an error, the caller's function will NOT be called.
913 * partid - ID of partition to which the channel is connected.
914 * ch_number - channel # to send message on.
915 * flags - see xp.h for valid flags.
916 * payload - pointer to the payload which is to be sent.
917 * payload_size - size of the payload in bytes.
918 * func - function to call with asynchronous notification of message
919 * receipt. THIS FUNCTION MUST BE NON-BLOCKING.
920 * key - user-defined key to be passed to the function when it's called.
923 xpc_initiate_send_notify(short partid
, int ch_number
, u32 flags
, void *payload
,
924 u16 payload_size
, xpc_notify_func func
, void *key
)
926 struct xpc_partition
*part
= &xpc_partitions
[partid
];
927 enum xp_retval ret
= xpUnknownReason
;
929 dev_dbg(xpc_chan
, "payload=0x%p, partid=%d, channel=%d\n", payload
,
932 DBUG_ON(partid
< 0 || partid
>= xp_max_npartitions
);
933 DBUG_ON(ch_number
< 0 || ch_number
>= part
->nchannels
);
934 DBUG_ON(payload
== NULL
);
935 DBUG_ON(func
== NULL
);
937 if (xpc_part_ref(part
)) {
938 ret
= xpc_arch_ops
.send_payload(&part
->channels
[ch_number
],
939 flags
, payload
, payload_size
, XPC_N_CALL
, func
, key
);
940 xpc_part_deref(part
);
946 * Deliver a message's payload to its intended recipient.
949 xpc_deliver_payload(struct xpc_channel
*ch
)
953 payload
= xpc_arch_ops
.get_deliverable_payload(ch
);
954 if (payload
!= NULL
) {
957 * This ref is taken to protect the payload itself from being
958 * freed before the user is finished with it, which the user
959 * indicates by calling xpc_initiate_received().
961 xpc_msgqueue_ref(ch
);
963 atomic_inc(&ch
->kthreads_active
);
965 if (ch
->func
!= NULL
) {
966 dev_dbg(xpc_chan
, "ch->func() called, payload=0x%p "
967 "partid=%d channel=%d\n", payload
, ch
->partid
,
970 /* deliver the message to its intended recipient */
971 ch
->func(xpMsgReceived
, ch
->partid
, ch
->number
, payload
,
974 dev_dbg(xpc_chan
, "ch->func() returned, payload=0x%p "
975 "partid=%d channel=%d\n", payload
, ch
->partid
,
979 atomic_dec(&ch
->kthreads_active
);
984 * Acknowledge receipt of a delivered message's payload.
986 * This function, although called by users, does not call xpc_part_ref() to
987 * ensure that the partition infrastructure is in place. It relies on the
988 * fact that we called xpc_msgqueue_ref() in xpc_deliver_payload().
992 * partid - ID of partition to which the channel is connected.
993 * ch_number - channel # message received on.
994 * payload - pointer to the payload area allocated via
995 * xpc_initiate_send() or xpc_initiate_send_notify().
998 xpc_initiate_received(short partid
, int ch_number
, void *payload
)
1000 struct xpc_partition
*part
= &xpc_partitions
[partid
];
1001 struct xpc_channel
*ch
;
1003 DBUG_ON(partid
< 0 || partid
>= xp_max_npartitions
);
1004 DBUG_ON(ch_number
< 0 || ch_number
>= part
->nchannels
);
1006 ch
= &part
->channels
[ch_number
];
1007 xpc_arch_ops
.received_payload(ch
, payload
);
1009 /* the call to xpc_msgqueue_ref() was done by xpc_deliver_payload() */
1010 xpc_msgqueue_deref(ch
);