sgi-xp: separate chctl_flags from XPC's notify IRQ
[linux-2.6/mini2440.git] / drivers / misc / sgi-xp / xpc_sn2.c
blob0fef7d86a5a2fe696293505f2012cf53c92f65af
1 /*
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
4 * for more details.
6 * Copyright (c) 2008 Silicon Graphics, Inc. All Rights Reserved.
7 */
9 /*
10 * Cross Partition Communication (XPC) sn2-based functions.
12 * Architecture specific implementation of common functions.
16 #include <linux/kernel.h>
17 #include <linux/delay.h>
18 #include <asm/uncached.h>
19 #include <asm/sn/sn_sal.h>
20 #include "xpc.h"
22 static struct xpc_vars_sn2 *xpc_vars; /* >>> Add _sn2 suffix? */
23 static struct xpc_vars_part_sn2 *xpc_vars_part; /* >>> Add _sn2 suffix? */
25 /* SH_IPI_ACCESS shub register value on startup */
26 static u64 xpc_sh1_IPI_access;
27 static u64 xpc_sh2_IPI_access0;
28 static u64 xpc_sh2_IPI_access1;
29 static u64 xpc_sh2_IPI_access2;
30 static u64 xpc_sh2_IPI_access3;
33 * Change protections to allow IPI operations.
35 static void
36 xpc_allow_IPI_ops_sn2(void)
38 int node;
39 int nasid;
41 /* >>> The following should get moved into SAL. */
42 if (is_shub2()) {
43 xpc_sh2_IPI_access0 =
44 (u64)HUB_L((u64 *)LOCAL_MMR_ADDR(SH2_IPI_ACCESS0));
45 xpc_sh2_IPI_access1 =
46 (u64)HUB_L((u64 *)LOCAL_MMR_ADDR(SH2_IPI_ACCESS1));
47 xpc_sh2_IPI_access2 =
48 (u64)HUB_L((u64 *)LOCAL_MMR_ADDR(SH2_IPI_ACCESS2));
49 xpc_sh2_IPI_access3 =
50 (u64)HUB_L((u64 *)LOCAL_MMR_ADDR(SH2_IPI_ACCESS3));
52 for_each_online_node(node) {
53 nasid = cnodeid_to_nasid(node);
54 HUB_S((u64 *)GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS0),
55 -1UL);
56 HUB_S((u64 *)GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS1),
57 -1UL);
58 HUB_S((u64 *)GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS2),
59 -1UL);
60 HUB_S((u64 *)GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS3),
61 -1UL);
63 } else {
64 xpc_sh1_IPI_access =
65 (u64)HUB_L((u64 *)LOCAL_MMR_ADDR(SH1_IPI_ACCESS));
67 for_each_online_node(node) {
68 nasid = cnodeid_to_nasid(node);
69 HUB_S((u64 *)GLOBAL_MMR_ADDR(nasid, SH1_IPI_ACCESS),
70 -1UL);
76 * Restrict protections to disallow IPI operations.
78 static void
79 xpc_disallow_IPI_ops_sn2(void)
81 int node;
82 int nasid;
84 /* >>> The following should get moved into SAL. */
85 if (is_shub2()) {
86 for_each_online_node(node) {
87 nasid = cnodeid_to_nasid(node);
88 HUB_S((u64 *)GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS0),
89 xpc_sh2_IPI_access0);
90 HUB_S((u64 *)GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS1),
91 xpc_sh2_IPI_access1);
92 HUB_S((u64 *)GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS2),
93 xpc_sh2_IPI_access2);
94 HUB_S((u64 *)GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS3),
95 xpc_sh2_IPI_access3);
97 } else {
98 for_each_online_node(node) {
99 nasid = cnodeid_to_nasid(node);
100 HUB_S((u64 *)GLOBAL_MMR_ADDR(nasid, SH1_IPI_ACCESS),
101 xpc_sh1_IPI_access);
107 * The following set of functions are used for the sending and receiving of
108 * IRQs (also known as IPIs). There are two flavors of IRQs, one that is
109 * associated with partition activity (SGI_XPC_ACTIVATE) and the other that
110 * is associated with channel activity (SGI_XPC_NOTIFY).
113 static u64
114 xpc_receive_IRQ_amo_sn2(AMO_t *amo)
116 return FETCHOP_LOAD_OP(TO_AMO((u64)&amo->variable), FETCHOP_CLEAR);
119 static enum xp_retval
120 xpc_send_IRQ_sn2(AMO_t *amo, u64 flag, int nasid, int phys_cpuid, int vector)
122 int ret = 0;
123 unsigned long irq_flags;
125 local_irq_save(irq_flags);
127 FETCHOP_STORE_OP(TO_AMO((u64)&amo->variable), FETCHOP_OR, flag);
128 sn_send_IPI_phys(nasid, phys_cpuid, vector, 0);
131 * We must always use the nofault function regardless of whether we
132 * are on a Shub 1.1 system or a Shub 1.2 slice 0xc processor. If we
133 * didn't, we'd never know that the other partition is down and would
134 * keep sending IRQs and AMOs to it until the heartbeat times out.
136 ret = xp_nofault_PIOR((u64 *)GLOBAL_MMR_ADDR(NASID_GET(&amo->variable),
137 xp_nofault_PIOR_target));
139 local_irq_restore(irq_flags);
141 return ((ret == 0) ? xpSuccess : xpPioReadError);
144 static AMO_t *
145 xpc_init_IRQ_amo_sn2(int index)
147 AMO_t *amo = xpc_vars->amos_page + index;
149 (void)xpc_receive_IRQ_amo_sn2(amo); /* clear AMO variable */
150 return amo;
154 * Functions associated with SGI_XPC_ACTIVATE IRQ.
158 * Notify the heartbeat check thread that an activate IRQ has been received.
160 static irqreturn_t
161 xpc_handle_activate_IRQ_sn2(int irq, void *dev_id)
163 atomic_inc(&xpc_activate_IRQ_rcvd);
164 wake_up_interruptible(&xpc_activate_IRQ_wq);
165 return IRQ_HANDLED;
169 * Flag the appropriate AMO variable and send an IRQ to the specified node.
171 static void
172 xpc_send_activate_IRQ_sn2(u64 amos_page_pa, int from_nasid, int to_nasid,
173 int to_phys_cpuid)
175 int w_index = XPC_NASID_W_INDEX(from_nasid);
176 int b_index = XPC_NASID_B_INDEX(from_nasid);
177 AMO_t *amos = (AMO_t *)__va(amos_page_pa +
178 (XPC_ACTIVATE_IRQ_AMOS * sizeof(AMO_t)));
180 (void)xpc_send_IRQ_sn2(&amos[w_index], (1UL << b_index), to_nasid,
181 to_phys_cpuid, SGI_XPC_ACTIVATE);
184 static void
185 xpc_send_local_activate_IRQ_sn2(int from_nasid)
187 int w_index = XPC_NASID_W_INDEX(from_nasid);
188 int b_index = XPC_NASID_B_INDEX(from_nasid);
189 AMO_t *amos = (AMO_t *)__va(xpc_vars->amos_page_pa +
190 (XPC_ACTIVATE_IRQ_AMOS * sizeof(AMO_t)));
192 /* fake the sending and receipt of an activate IRQ from remote nasid */
193 FETCHOP_STORE_OP(TO_AMO((u64)&amos[w_index].variable), FETCHOP_OR,
194 (1UL << b_index));
195 atomic_inc(&xpc_activate_IRQ_rcvd);
196 wake_up_interruptible(&xpc_activate_IRQ_wq);
200 * Functions associated with SGI_XPC_NOTIFY IRQ.
204 * Check to see if any chctl flags were sent from the specified partition.
206 static void
207 xpc_check_for_sent_chctl_flags_sn2(struct xpc_partition *part)
209 union xpc_channel_ctl_flags chctl;
210 unsigned long irq_flags;
212 chctl.all_flags = xpc_receive_IRQ_amo_sn2(part->sn.sn2.
213 local_chctl_amo_va);
214 if (chctl.all_flags == 0)
215 return;
217 spin_lock_irqsave(&part->chctl_lock, irq_flags);
218 part->chctl.all_flags |= chctl.all_flags;
219 spin_unlock_irqrestore(&part->chctl_lock, irq_flags);
221 dev_dbg(xpc_chan, "received notify IRQ from partid=%d, chctl.all_flags="
222 "0x%lx\n", XPC_PARTID(part), chctl.all_flags);
224 xpc_wakeup_channel_mgr(part);
228 * Handle the receipt of a SGI_XPC_NOTIFY IRQ by seeing whether the specified
229 * partition actually sent it. Since SGI_XPC_NOTIFY IRQs may be shared by more
230 * than one partition, we use an AMO_t structure per partition to indicate
231 * whether a partition has sent an IRQ or not. If it has, then wake up the
232 * associated kthread to handle it.
234 * All SGI_XPC_NOTIFY IRQs received by XPC are the result of IRQs sent by XPC
235 * running on other partitions.
237 * Noteworthy Arguments:
239 * irq - Interrupt ReQuest number. NOT USED.
241 * dev_id - partid of IRQ's potential sender.
243 static irqreturn_t
244 xpc_handle_notify_IRQ_sn2(int irq, void *dev_id)
246 short partid = (short)(u64)dev_id;
247 struct xpc_partition *part = &xpc_partitions[partid];
249 DBUG_ON(partid < 0 || partid >= xp_max_npartitions);
251 if (xpc_part_ref(part)) {
252 xpc_check_for_sent_chctl_flags_sn2(part);
254 xpc_part_deref(part);
256 return IRQ_HANDLED;
260 * Check to see if xpc_handle_notify_IRQ_sn2() dropped any IRQs on the floor
261 * because the write to their associated amo variable completed after the IRQ
262 * was received.
264 static void
265 xpc_check_for_dropped_notify_IRQ_sn2(struct xpc_partition *part)
267 struct xpc_partition_sn2 *part_sn2 = &part->sn.sn2;
269 if (xpc_part_ref(part)) {
270 xpc_check_for_sent_chctl_flags_sn2(part);
272 part_sn2->dropped_notify_IRQ_timer.expires = jiffies +
273 XPC_DROPPED_NOTIFY_IRQ_WAIT_INTERVAL;
274 add_timer(&part_sn2->dropped_notify_IRQ_timer);
275 xpc_part_deref(part);
280 * Send a notify IRQ to the remote partition that is associated with the
281 * specified channel.
283 static void
284 xpc_send_notify_IRQ_sn2(struct xpc_channel *ch, u8 chctl_flag,
285 char *chctl_flag_string, unsigned long *irq_flags)
287 struct xpc_partition *part = &xpc_partitions[ch->partid];
288 struct xpc_partition_sn2 *part_sn2 = &part->sn.sn2;
289 union xpc_channel_ctl_flags chctl = { 0 };
290 enum xp_retval ret;
292 if (likely(part->act_state != XPC_P_DEACTIVATING)) {
293 chctl.flags[ch->number] = chctl_flag;
294 ret = xpc_send_IRQ_sn2(part_sn2->remote_chctl_amo_va,
295 chctl.all_flags,
296 part_sn2->notify_IRQ_nasid,
297 part_sn2->notify_IRQ_phys_cpuid,
298 SGI_XPC_NOTIFY);
299 dev_dbg(xpc_chan, "%s sent to partid=%d, channel=%d, ret=%d\n",
300 chctl_flag_string, ch->partid, ch->number, ret);
301 if (unlikely(ret != xpSuccess)) {
302 if (irq_flags != NULL)
303 spin_unlock_irqrestore(&ch->lock, *irq_flags);
304 XPC_DEACTIVATE_PARTITION(part, ret);
305 if (irq_flags != NULL)
306 spin_lock_irqsave(&ch->lock, *irq_flags);
311 #define XPC_SEND_NOTIFY_IRQ_SN2(_ch, _ipi_f, _irq_f) \
312 xpc_send_notify_IRQ_sn2(_ch, _ipi_f, #_ipi_f, _irq_f)
315 * Make it look like the remote partition, which is associated with the
316 * specified channel, sent us a notify IRQ. This faked IRQ will be handled
317 * by xpc_check_for_dropped_notify_IRQ_sn2().
319 static void
320 xpc_send_local_notify_IRQ_sn2(struct xpc_channel *ch, u8 chctl_flag,
321 char *chctl_flag_string)
323 struct xpc_partition *part = &xpc_partitions[ch->partid];
324 union xpc_channel_ctl_flags chctl = { 0 };
326 chctl.flags[ch->number] = chctl_flag;
327 FETCHOP_STORE_OP(TO_AMO((u64)&part->sn.sn2.local_chctl_amo_va->
328 variable), FETCHOP_OR, chctl.all_flags);
329 dev_dbg(xpc_chan, "%s sent local from partid=%d, channel=%d\n",
330 chctl_flag_string, ch->partid, ch->number);
333 #define XPC_SEND_LOCAL_NOTIFY_IRQ_SN2(_ch, _ipi_f) \
334 xpc_send_local_notify_IRQ_sn2(_ch, _ipi_f, #_ipi_f)
336 static void
337 xpc_send_chctl_closerequest_sn2(struct xpc_channel *ch,
338 unsigned long *irq_flags)
340 struct xpc_openclose_args *args = ch->local_openclose_args;
342 args->reason = ch->reason;
343 XPC_SEND_NOTIFY_IRQ_SN2(ch, XPC_CHCTL_CLOSEREQUEST, irq_flags);
346 static void
347 xpc_send_chctl_closereply_sn2(struct xpc_channel *ch, unsigned long *irq_flags)
349 XPC_SEND_NOTIFY_IRQ_SN2(ch, XPC_CHCTL_CLOSEREPLY, irq_flags);
352 static void
353 xpc_send_chctl_openrequest_sn2(struct xpc_channel *ch, unsigned long *irq_flags)
355 struct xpc_openclose_args *args = ch->local_openclose_args;
357 args->msg_size = ch->msg_size;
358 args->local_nentries = ch->local_nentries;
359 XPC_SEND_NOTIFY_IRQ_SN2(ch, XPC_CHCTL_OPENREQUEST, irq_flags);
362 static void
363 xpc_send_chctl_openreply_sn2(struct xpc_channel *ch, unsigned long *irq_flags)
365 struct xpc_openclose_args *args = ch->local_openclose_args;
367 args->remote_nentries = ch->remote_nentries;
368 args->local_nentries = ch->local_nentries;
369 args->local_msgqueue_pa = __pa(ch->local_msgqueue);
370 XPC_SEND_NOTIFY_IRQ_SN2(ch, XPC_CHCTL_OPENREPLY, irq_flags);
373 static void
374 xpc_send_chctl_msgrequest_sn2(struct xpc_channel *ch)
376 XPC_SEND_NOTIFY_IRQ_SN2(ch, XPC_CHCTL_MSGREQUEST, NULL);
379 static void
380 xpc_send_chctl_local_msgrequest_sn2(struct xpc_channel *ch)
382 XPC_SEND_LOCAL_NOTIFY_IRQ_SN2(ch, XPC_CHCTL_MSGREQUEST);
386 * This next set of functions are used to keep track of when a partition is
387 * potentially engaged in accessing memory belonging to another partition.
390 static void
391 xpc_indicate_partition_engaged_sn2(struct xpc_partition *part)
393 unsigned long irq_flags;
394 AMO_t *amo = (AMO_t *)__va(part->sn.sn2.remote_amos_page_pa +
395 (XPC_ENGAGED_PARTITIONS_AMO *
396 sizeof(AMO_t)));
398 local_irq_save(irq_flags);
400 /* set bit corresponding to our partid in remote partition's AMO */
401 FETCHOP_STORE_OP(TO_AMO((u64)&amo->variable), FETCHOP_OR,
402 (1UL << sn_partition_id));
404 * We must always use the nofault function regardless of whether we
405 * are on a Shub 1.1 system or a Shub 1.2 slice 0xc processor. If we
406 * didn't, we'd never know that the other partition is down and would
407 * keep sending IRQs and AMOs to it until the heartbeat times out.
409 (void)xp_nofault_PIOR((u64 *)GLOBAL_MMR_ADDR(NASID_GET(&amo->
410 variable),
411 xp_nofault_PIOR_target));
413 local_irq_restore(irq_flags);
416 static void
417 xpc_indicate_partition_disengaged_sn2(struct xpc_partition *part)
419 struct xpc_partition_sn2 *part_sn2 = &part->sn.sn2;
420 unsigned long irq_flags;
421 AMO_t *amo = (AMO_t *)__va(part_sn2->remote_amos_page_pa +
422 (XPC_ENGAGED_PARTITIONS_AMO *
423 sizeof(AMO_t)));
425 local_irq_save(irq_flags);
427 /* clear bit corresponding to our partid in remote partition's AMO */
428 FETCHOP_STORE_OP(TO_AMO((u64)&amo->variable), FETCHOP_AND,
429 ~(1UL << sn_partition_id));
431 * We must always use the nofault function regardless of whether we
432 * are on a Shub 1.1 system or a Shub 1.2 slice 0xc processor. If we
433 * didn't, we'd never know that the other partition is down and would
434 * keep sending IRQs and AMOs to it until the heartbeat times out.
436 (void)xp_nofault_PIOR((u64 *)GLOBAL_MMR_ADDR(NASID_GET(&amo->
437 variable),
438 xp_nofault_PIOR_target));
440 local_irq_restore(irq_flags);
443 * Send activate IRQ to get other side to see that we've cleared our
444 * bit in their engaged partitions AMO.
446 xpc_send_activate_IRQ_sn2(part_sn2->remote_amos_page_pa,
447 cnodeid_to_nasid(0),
448 part_sn2->activate_IRQ_nasid,
449 part_sn2->activate_IRQ_phys_cpuid);
452 static int
453 xpc_partition_engaged_sn2(short partid)
455 AMO_t *amo = xpc_vars->amos_page + XPC_ENGAGED_PARTITIONS_AMO;
457 /* our partition's AMO variable ANDed with partid mask */
458 return (FETCHOP_LOAD_OP(TO_AMO((u64)&amo->variable), FETCHOP_LOAD) &
459 (1UL << partid)) != 0;
462 static int
463 xpc_any_partition_engaged_sn2(void)
465 AMO_t *amo = xpc_vars->amos_page + XPC_ENGAGED_PARTITIONS_AMO;
467 /* our partition's AMO variable */
468 return FETCHOP_LOAD_OP(TO_AMO((u64)&amo->variable), FETCHOP_LOAD) != 0;
471 static void
472 xpc_assume_partition_disengaged_sn2(short partid)
474 AMO_t *amo = xpc_vars->amos_page + XPC_ENGAGED_PARTITIONS_AMO;
476 /* clear bit(s) based on partid mask in our partition's AMO */
477 FETCHOP_STORE_OP(TO_AMO((u64)&amo->variable), FETCHOP_AND,
478 ~(1UL << partid));
481 /* original protection values for each node */
482 static u64 xpc_prot_vec_sn2[MAX_NUMNODES];
485 * Change protections to allow AMO operations on non-Shub 1.1 systems.
487 static enum xp_retval
488 xpc_allow_AMO_ops_sn2(AMO_t *amos_page)
490 u64 nasid_array = 0;
491 int ret;
494 * On SHUB 1.1, we cannot call sn_change_memprotect() since the BIST
495 * collides with memory operations. On those systems we call
496 * xpc_allow_AMO_ops_shub_wars_1_1_sn2() instead.
498 if (!enable_shub_wars_1_1()) {
499 ret = sn_change_memprotect(ia64_tpa((u64)amos_page), PAGE_SIZE,
500 SN_MEMPROT_ACCESS_CLASS_1,
501 &nasid_array);
502 if (ret != 0)
503 return xpSalError;
505 return xpSuccess;
509 * Change protections to allow AMO operations on Shub 1.1 systems.
511 static void
512 xpc_allow_AMO_ops_shub_wars_1_1_sn2(void)
514 int node;
515 int nasid;
517 if (!enable_shub_wars_1_1())
518 return;
520 for_each_online_node(node) {
521 nasid = cnodeid_to_nasid(node);
522 /* save current protection values */
523 xpc_prot_vec_sn2[node] =
524 (u64)HUB_L((u64 *)GLOBAL_MMR_ADDR(nasid,
525 SH1_MD_DQLP_MMR_DIR_PRIVEC0));
526 /* open up everything */
527 HUB_S((u64 *)GLOBAL_MMR_ADDR(nasid,
528 SH1_MD_DQLP_MMR_DIR_PRIVEC0),
529 -1UL);
530 HUB_S((u64 *)GLOBAL_MMR_ADDR(nasid,
531 SH1_MD_DQRP_MMR_DIR_PRIVEC0),
532 -1UL);
536 static enum xp_retval
537 xpc_rsvd_page_init_sn2(struct xpc_rsvd_page *rp)
539 AMO_t *amos_page;
540 int i;
541 int ret;
543 xpc_vars = XPC_RP_VARS(rp);
545 rp->sn.vars_pa = __pa(xpc_vars);
547 /* vars_part array follows immediately after vars */
548 xpc_vars_part = (struct xpc_vars_part_sn2 *)((u8 *)XPC_RP_VARS(rp) +
549 XPC_RP_VARS_SIZE);
552 * Before clearing xpc_vars, see if a page of AMOs had been previously
553 * allocated. If not we'll need to allocate one and set permissions
554 * so that cross-partition AMOs are allowed.
556 * The allocated AMO page needs MCA reporting to remain disabled after
557 * XPC has unloaded. To make this work, we keep a copy of the pointer
558 * to this page (i.e., amos_page) in the struct xpc_vars structure,
559 * which is pointed to by the reserved page, and re-use that saved copy
560 * on subsequent loads of XPC. This AMO page is never freed, and its
561 * memory protections are never restricted.
563 amos_page = xpc_vars->amos_page;
564 if (amos_page == NULL) {
565 amos_page = (AMO_t *)TO_AMO(uncached_alloc_page(0, 1));
566 if (amos_page == NULL) {
567 dev_err(xpc_part, "can't allocate page of AMOs\n");
568 return xpNoMemory;
572 * Open up AMO-R/W to cpu. This is done on Shub 1.1 systems
573 * when xpc_allow_AMO_ops_shub_wars_1_1_sn2() is called.
575 ret = xpc_allow_AMO_ops_sn2(amos_page);
576 if (ret != xpSuccess) {
577 dev_err(xpc_part, "can't allow AMO operations\n");
578 uncached_free_page(__IA64_UNCACHED_OFFSET |
579 TO_PHYS((u64)amos_page), 1);
580 return ret;
584 /* clear xpc_vars */
585 memset(xpc_vars, 0, sizeof(struct xpc_vars_sn2));
587 xpc_vars->version = XPC_V_VERSION;
588 xpc_vars->activate_IRQ_nasid = cpuid_to_nasid(0);
589 xpc_vars->activate_IRQ_phys_cpuid = cpu_physical_id(0);
590 xpc_vars->vars_part_pa = __pa(xpc_vars_part);
591 xpc_vars->amos_page_pa = ia64_tpa((u64)amos_page);
592 xpc_vars->amos_page = amos_page; /* save for next load of XPC */
594 /* clear xpc_vars_part */
595 memset((u64 *)xpc_vars_part, 0, sizeof(struct xpc_vars_part_sn2) *
596 xp_max_npartitions);
598 /* initialize the activate IRQ related AMO variables */
599 for (i = 0; i < xp_nasid_mask_words; i++)
600 (void)xpc_init_IRQ_amo_sn2(XPC_ACTIVATE_IRQ_AMOS + i);
602 /* initialize the engaged remote partitions related AMO variables */
603 (void)xpc_init_IRQ_amo_sn2(XPC_ENGAGED_PARTITIONS_AMO);
604 (void)xpc_init_IRQ_amo_sn2(XPC_DEACTIVATE_REQUEST_AMO);
606 return xpSuccess;
609 static void
610 xpc_increment_heartbeat_sn2(void)
612 xpc_vars->heartbeat++;
615 static void
616 xpc_offline_heartbeat_sn2(void)
618 xpc_increment_heartbeat_sn2();
619 xpc_vars->heartbeat_offline = 1;
622 static void
623 xpc_online_heartbeat_sn2(void)
625 xpc_increment_heartbeat_sn2();
626 xpc_vars->heartbeat_offline = 0;
629 static void
630 xpc_heartbeat_init_sn2(void)
632 DBUG_ON(xpc_vars == NULL);
634 bitmap_zero(xpc_vars->heartbeating_to_mask, XP_MAX_NPARTITIONS_SN2);
635 xpc_heartbeating_to_mask = &xpc_vars->heartbeating_to_mask[0];
636 xpc_online_heartbeat_sn2();
639 static void
640 xpc_heartbeat_exit_sn2(void)
642 xpc_offline_heartbeat_sn2();
646 * At periodic intervals, scan through all active partitions and ensure
647 * their heartbeat is still active. If not, the partition is deactivated.
649 static void
650 xpc_check_remote_hb_sn2(void)
652 struct xpc_vars_sn2 *remote_vars;
653 struct xpc_partition *part;
654 short partid;
655 enum xp_retval ret;
657 remote_vars = (struct xpc_vars_sn2 *)xpc_remote_copy_buffer;
659 for (partid = 0; partid < xp_max_npartitions; partid++) {
661 if (xpc_exiting)
662 break;
664 if (partid == sn_partition_id)
665 continue;
667 part = &xpc_partitions[partid];
669 if (part->act_state == XPC_P_INACTIVE ||
670 part->act_state == XPC_P_DEACTIVATING) {
671 continue;
674 /* pull the remote_hb cache line */
675 ret = xp_remote_memcpy(remote_vars,
676 (void *)part->sn.sn2.remote_vars_pa,
677 XPC_RP_VARS_SIZE);
678 if (ret != xpSuccess) {
679 XPC_DEACTIVATE_PARTITION(part, ret);
680 continue;
683 dev_dbg(xpc_part, "partid = %d, heartbeat = %ld, last_heartbeat"
684 " = %ld, heartbeat_offline = %ld, HB_mask[0] = 0x%lx\n",
685 partid, remote_vars->heartbeat, part->last_heartbeat,
686 remote_vars->heartbeat_offline,
687 remote_vars->heartbeating_to_mask[0]);
689 if (((remote_vars->heartbeat == part->last_heartbeat) &&
690 (remote_vars->heartbeat_offline == 0)) ||
691 !xpc_hb_allowed(sn_partition_id,
692 &remote_vars->heartbeating_to_mask)) {
694 XPC_DEACTIVATE_PARTITION(part, xpNoHeartbeat);
695 continue;
698 part->last_heartbeat = remote_vars->heartbeat;
703 * Get a copy of the remote partition's XPC variables from the reserved page.
705 * remote_vars points to a buffer that is cacheline aligned for BTE copies and
706 * assumed to be of size XPC_RP_VARS_SIZE.
708 static enum xp_retval
709 xpc_get_remote_vars_sn2(u64 remote_vars_pa, struct xpc_vars_sn2 *remote_vars)
711 enum xp_retval ret;
713 if (remote_vars_pa == 0)
714 return xpVarsNotSet;
716 /* pull over the cross partition variables */
717 ret = xp_remote_memcpy(remote_vars, (void *)remote_vars_pa,
718 XPC_RP_VARS_SIZE);
719 if (ret != xpSuccess)
720 return ret;
722 if (XPC_VERSION_MAJOR(remote_vars->version) !=
723 XPC_VERSION_MAJOR(XPC_V_VERSION)) {
724 return xpBadVersion;
727 return xpSuccess;
730 static void
731 xpc_request_partition_activation_sn2(struct xpc_rsvd_page *remote_rp,
732 u64 remote_rp_pa, int nasid)
734 xpc_send_local_activate_IRQ_sn2(nasid);
737 static void
738 xpc_request_partition_reactivation_sn2(struct xpc_partition *part)
740 xpc_send_local_activate_IRQ_sn2(part->sn.sn2.activate_IRQ_nasid);
743 static void
744 xpc_request_partition_deactivation_sn2(struct xpc_partition *part)
746 struct xpc_partition_sn2 *part_sn2 = &part->sn.sn2;
747 unsigned long irq_flags;
748 AMO_t *amo = (AMO_t *)__va(part_sn2->remote_amos_page_pa +
749 (XPC_DEACTIVATE_REQUEST_AMO * sizeof(AMO_t)));
751 local_irq_save(irq_flags);
753 /* set bit corresponding to our partid in remote partition's AMO */
754 FETCHOP_STORE_OP(TO_AMO((u64)&amo->variable), FETCHOP_OR,
755 (1UL << sn_partition_id));
757 * We must always use the nofault function regardless of whether we
758 * are on a Shub 1.1 system or a Shub 1.2 slice 0xc processor. If we
759 * didn't, we'd never know that the other partition is down and would
760 * keep sending IRQs and AMOs to it until the heartbeat times out.
762 (void)xp_nofault_PIOR((u64 *)GLOBAL_MMR_ADDR(NASID_GET(&amo->
763 variable),
764 xp_nofault_PIOR_target));
766 local_irq_restore(irq_flags);
769 * Send activate IRQ to get other side to see that we've set our
770 * bit in their deactivate request AMO.
772 xpc_send_activate_IRQ_sn2(part_sn2->remote_amos_page_pa,
773 cnodeid_to_nasid(0),
774 part_sn2->activate_IRQ_nasid,
775 part_sn2->activate_IRQ_phys_cpuid);
778 static void
779 xpc_cancel_partition_deactivation_request_sn2(struct xpc_partition *part)
781 unsigned long irq_flags;
782 AMO_t *amo = (AMO_t *)__va(part->sn.sn2.remote_amos_page_pa +
783 (XPC_DEACTIVATE_REQUEST_AMO * sizeof(AMO_t)));
785 local_irq_save(irq_flags);
787 /* clear bit corresponding to our partid in remote partition's AMO */
788 FETCHOP_STORE_OP(TO_AMO((u64)&amo->variable), FETCHOP_AND,
789 ~(1UL << sn_partition_id));
791 * We must always use the nofault function regardless of whether we
792 * are on a Shub 1.1 system or a Shub 1.2 slice 0xc processor. If we
793 * didn't, we'd never know that the other partition is down and would
794 * keep sending IRQs and AMOs to it until the heartbeat times out.
796 (void)xp_nofault_PIOR((u64 *)GLOBAL_MMR_ADDR(NASID_GET(&amo->
797 variable),
798 xp_nofault_PIOR_target));
800 local_irq_restore(irq_flags);
803 static int
804 xpc_partition_deactivation_requested_sn2(short partid)
806 AMO_t *amo = xpc_vars->amos_page + XPC_DEACTIVATE_REQUEST_AMO;
808 /* our partition's AMO variable ANDed with partid mask */
809 return (FETCHOP_LOAD_OP(TO_AMO((u64)&amo->variable), FETCHOP_LOAD) &
810 (1UL << partid)) != 0;
814 * Update the remote partition's info.
816 static void
817 xpc_update_partition_info_sn2(struct xpc_partition *part, u8 remote_rp_version,
818 unsigned long *remote_rp_stamp, u64 remote_rp_pa,
819 u64 remote_vars_pa,
820 struct xpc_vars_sn2 *remote_vars)
822 struct xpc_partition_sn2 *part_sn2 = &part->sn.sn2;
824 part->remote_rp_version = remote_rp_version;
825 dev_dbg(xpc_part, " remote_rp_version = 0x%016x\n",
826 part->remote_rp_version);
828 part->remote_rp_stamp = *remote_rp_stamp;
829 dev_dbg(xpc_part, " remote_rp_stamp = 0x%016lx\n",
830 part->remote_rp_stamp);
832 part->remote_rp_pa = remote_rp_pa;
833 dev_dbg(xpc_part, " remote_rp_pa = 0x%016lx\n", part->remote_rp_pa);
835 part_sn2->remote_vars_pa = remote_vars_pa;
836 dev_dbg(xpc_part, " remote_vars_pa = 0x%016lx\n",
837 part_sn2->remote_vars_pa);
839 part->last_heartbeat = remote_vars->heartbeat;
840 dev_dbg(xpc_part, " last_heartbeat = 0x%016lx\n",
841 part->last_heartbeat);
843 part_sn2->remote_vars_part_pa = remote_vars->vars_part_pa;
844 dev_dbg(xpc_part, " remote_vars_part_pa = 0x%016lx\n",
845 part_sn2->remote_vars_part_pa);
847 part_sn2->activate_IRQ_nasid = remote_vars->activate_IRQ_nasid;
848 dev_dbg(xpc_part, " activate_IRQ_nasid = 0x%x\n",
849 part_sn2->activate_IRQ_nasid);
851 part_sn2->activate_IRQ_phys_cpuid =
852 remote_vars->activate_IRQ_phys_cpuid;
853 dev_dbg(xpc_part, " activate_IRQ_phys_cpuid = 0x%x\n",
854 part_sn2->activate_IRQ_phys_cpuid);
856 part_sn2->remote_amos_page_pa = remote_vars->amos_page_pa;
857 dev_dbg(xpc_part, " remote_amos_page_pa = 0x%lx\n",
858 part_sn2->remote_amos_page_pa);
860 part_sn2->remote_vars_version = remote_vars->version;
861 dev_dbg(xpc_part, " remote_vars_version = 0x%x\n",
862 part_sn2->remote_vars_version);
866 * Prior code has determined the nasid which generated a activate IRQ.
867 * Inspect that nasid to determine if its partition needs to be activated
868 * or deactivated.
870 * A partition is considered "awaiting activation" if our partition
871 * flags indicate it is not active and it has a heartbeat. A
872 * partition is considered "awaiting deactivation" if our partition
873 * flags indicate it is active but it has no heartbeat or it is not
874 * sending its heartbeat to us.
876 * To determine the heartbeat, the remote nasid must have a properly
877 * initialized reserved page.
879 static void
880 xpc_identify_activate_IRQ_req_sn2(int nasid)
882 struct xpc_rsvd_page *remote_rp;
883 struct xpc_vars_sn2 *remote_vars;
884 u64 remote_rp_pa;
885 u64 remote_vars_pa;
886 int remote_rp_version;
887 int reactivate = 0;
888 unsigned long remote_rp_stamp = 0;
889 short partid;
890 struct xpc_partition *part;
891 struct xpc_partition_sn2 *part_sn2;
892 enum xp_retval ret;
894 /* pull over the reserved page structure */
896 remote_rp = (struct xpc_rsvd_page *)xpc_remote_copy_buffer;
898 ret = xpc_get_remote_rp(nasid, NULL, remote_rp, &remote_rp_pa);
899 if (ret != xpSuccess) {
900 dev_warn(xpc_part, "unable to get reserved page from nasid %d, "
901 "which sent interrupt, reason=%d\n", nasid, ret);
902 return;
905 remote_vars_pa = remote_rp->sn.vars_pa;
906 remote_rp_version = remote_rp->version;
907 remote_rp_stamp = remote_rp->stamp;
909 partid = remote_rp->SAL_partid;
910 part = &xpc_partitions[partid];
911 part_sn2 = &part->sn.sn2;
913 /* pull over the cross partition variables */
915 remote_vars = (struct xpc_vars_sn2 *)xpc_remote_copy_buffer;
917 ret = xpc_get_remote_vars_sn2(remote_vars_pa, remote_vars);
918 if (ret != xpSuccess) {
919 dev_warn(xpc_part, "unable to get XPC variables from nasid %d, "
920 "which sent interrupt, reason=%d\n", nasid, ret);
922 XPC_DEACTIVATE_PARTITION(part, ret);
923 return;
926 part->activate_IRQ_rcvd++;
928 dev_dbg(xpc_part, "partid for nasid %d is %d; IRQs = %d; HB = "
929 "%ld:0x%lx\n", (int)nasid, (int)partid, part->activate_IRQ_rcvd,
930 remote_vars->heartbeat, remote_vars->heartbeating_to_mask[0]);
932 if (xpc_partition_disengaged(part) &&
933 part->act_state == XPC_P_INACTIVE) {
935 xpc_update_partition_info_sn2(part, remote_rp_version,
936 &remote_rp_stamp, remote_rp_pa,
937 remote_vars_pa, remote_vars);
939 if (xpc_partition_deactivation_requested_sn2(partid)) {
941 * Other side is waiting on us to deactivate even though
942 * we already have.
944 return;
947 xpc_activate_partition(part);
948 return;
951 DBUG_ON(part->remote_rp_version == 0);
952 DBUG_ON(part_sn2->remote_vars_version == 0);
954 if (remote_rp_stamp != part->remote_rp_stamp) {
956 /* the other side rebooted */
958 DBUG_ON(xpc_partition_engaged_sn2(partid));
959 DBUG_ON(xpc_partition_deactivation_requested_sn2(partid));
961 xpc_update_partition_info_sn2(part, remote_rp_version,
962 &remote_rp_stamp, remote_rp_pa,
963 remote_vars_pa, remote_vars);
964 reactivate = 1;
967 if (part->disengage_timeout > 0 && !xpc_partition_disengaged(part)) {
968 /* still waiting on other side to disengage from us */
969 return;
972 if (reactivate)
973 XPC_DEACTIVATE_PARTITION(part, xpReactivating);
974 else if (xpc_partition_deactivation_requested_sn2(partid))
975 XPC_DEACTIVATE_PARTITION(part, xpOtherGoingDown);
979 * Loop through the activation AMO variables and process any bits
980 * which are set. Each bit indicates a nasid sending a partition
981 * activation or deactivation request.
983 * Return #of IRQs detected.
986 xpc_identify_activate_IRQ_sender_sn2(void)
988 int word, bit;
989 u64 nasid_mask;
990 u64 nasid; /* remote nasid */
991 int n_IRQs_detected = 0;
992 AMO_t *act_amos;
994 act_amos = xpc_vars->amos_page + XPC_ACTIVATE_IRQ_AMOS;
996 /* scan through act AMO variable looking for non-zero entries */
997 for (word = 0; word < xp_nasid_mask_words; word++) {
999 if (xpc_exiting)
1000 break;
1002 nasid_mask = xpc_receive_IRQ_amo_sn2(&act_amos[word]);
1003 if (nasid_mask == 0) {
1004 /* no IRQs from nasids in this variable */
1005 continue;
1008 dev_dbg(xpc_part, "AMO[%d] gave back 0x%lx\n", word,
1009 nasid_mask);
1012 * If this nasid has been added to the machine since
1013 * our partition was reset, this will retain the
1014 * remote nasid in our reserved pages machine mask.
1015 * This is used in the event of module reload.
1017 xpc_mach_nasids[word] |= nasid_mask;
1019 /* locate the nasid(s) which sent interrupts */
1021 for (bit = 0; bit < (8 * sizeof(u64)); bit++) {
1022 if (nasid_mask & (1UL << bit)) {
1023 n_IRQs_detected++;
1024 nasid = XPC_NASID_FROM_W_B(word, bit);
1025 dev_dbg(xpc_part, "interrupt from nasid %ld\n",
1026 nasid);
1027 xpc_identify_activate_IRQ_req_sn2(nasid);
1031 return n_IRQs_detected;
1034 static void
1035 xpc_process_activate_IRQ_rcvd_sn2(int n_IRQs_expected)
1037 int n_IRQs_detected;
1039 n_IRQs_detected = xpc_identify_activate_IRQ_sender_sn2();
1040 if (n_IRQs_detected < n_IRQs_expected) {
1041 /* retry once to help avoid missing AMO */
1042 (void)xpc_identify_activate_IRQ_sender_sn2();
1047 * Setup the infrastructure necessary to support XPartition Communication
1048 * between the specified remote partition and the local one.
1050 static enum xp_retval
1051 xpc_setup_infrastructure_sn2(struct xpc_partition *part)
1053 struct xpc_partition_sn2 *part_sn2 = &part->sn.sn2;
1054 enum xp_retval retval;
1055 int ret;
1056 int cpuid;
1057 int ch_number;
1058 struct xpc_channel *ch;
1059 struct timer_list *timer;
1060 short partid = XPC_PARTID(part);
1063 * Allocate all of the channel structures as a contiguous chunk of
1064 * memory.
1066 DBUG_ON(part->channels != NULL);
1067 part->channels = kzalloc(sizeof(struct xpc_channel) * XPC_MAX_NCHANNELS,
1068 GFP_KERNEL);
1069 if (part->channels == NULL) {
1070 dev_err(xpc_chan, "can't get memory for channels\n");
1071 return xpNoMemory;
1074 /* allocate all the required GET/PUT values */
1076 part_sn2->local_GPs = xpc_kzalloc_cacheline_aligned(XPC_GP_SIZE,
1077 GFP_KERNEL,
1078 &part_sn2->
1079 local_GPs_base);
1080 if (part_sn2->local_GPs == NULL) {
1081 dev_err(xpc_chan, "can't get memory for local get/put "
1082 "values\n");
1083 retval = xpNoMemory;
1084 goto out_1;
1087 part_sn2->remote_GPs = xpc_kzalloc_cacheline_aligned(XPC_GP_SIZE,
1088 GFP_KERNEL,
1089 &part_sn2->
1090 remote_GPs_base);
1091 if (part_sn2->remote_GPs == NULL) {
1092 dev_err(xpc_chan, "can't get memory for remote get/put "
1093 "values\n");
1094 retval = xpNoMemory;
1095 goto out_2;
1098 part_sn2->remote_GPs_pa = 0;
1100 /* allocate all the required open and close args */
1102 part->local_openclose_args =
1103 xpc_kzalloc_cacheline_aligned(XPC_OPENCLOSE_ARGS_SIZE, GFP_KERNEL,
1104 &part->local_openclose_args_base);
1105 if (part->local_openclose_args == NULL) {
1106 dev_err(xpc_chan, "can't get memory for local connect args\n");
1107 retval = xpNoMemory;
1108 goto out_3;
1111 part->remote_openclose_args =
1112 xpc_kzalloc_cacheline_aligned(XPC_OPENCLOSE_ARGS_SIZE, GFP_KERNEL,
1113 &part->remote_openclose_args_base);
1114 if (part->remote_openclose_args == NULL) {
1115 dev_err(xpc_chan, "can't get memory for remote connect args\n");
1116 retval = xpNoMemory;
1117 goto out_4;
1120 part_sn2->remote_openclose_args_pa = 0;
1122 part_sn2->local_chctl_amo_va = xpc_init_IRQ_amo_sn2(partid);
1123 part->chctl.all_flags = 0;
1124 spin_lock_init(&part->chctl_lock);
1126 part_sn2->notify_IRQ_nasid = 0;
1127 part_sn2->notify_IRQ_phys_cpuid = 0;
1128 part_sn2->remote_chctl_amo_va = NULL;
1130 atomic_set(&part->channel_mgr_requests, 1);
1131 init_waitqueue_head(&part->channel_mgr_wq);
1133 sprintf(part_sn2->notify_IRQ_owner, "xpc%02d", partid);
1134 ret = request_irq(SGI_XPC_NOTIFY, xpc_handle_notify_IRQ_sn2,
1135 IRQF_SHARED, part_sn2->notify_IRQ_owner,
1136 (void *)(u64)partid);
1137 if (ret != 0) {
1138 dev_err(xpc_chan, "can't register NOTIFY IRQ handler, "
1139 "errno=%d\n", -ret);
1140 retval = xpLackOfResources;
1141 goto out_5;
1144 /* Setup a timer to check for dropped notify IRQs */
1145 timer = &part_sn2->dropped_notify_IRQ_timer;
1146 init_timer(timer);
1147 timer->function =
1148 (void (*)(unsigned long))xpc_check_for_dropped_notify_IRQ_sn2;
1149 timer->data = (unsigned long)part;
1150 timer->expires = jiffies + XPC_DROPPED_NOTIFY_IRQ_WAIT_INTERVAL;
1151 add_timer(timer);
1153 part->nchannels = XPC_MAX_NCHANNELS;
1155 atomic_set(&part->nchannels_active, 0);
1156 atomic_set(&part->nchannels_engaged, 0);
1158 for (ch_number = 0; ch_number < part->nchannels; ch_number++) {
1159 ch = &part->channels[ch_number];
1161 ch->partid = partid;
1162 ch->number = ch_number;
1163 ch->flags = XPC_C_DISCONNECTED;
1165 ch->sn.sn2.local_GP = &part_sn2->local_GPs[ch_number];
1166 ch->local_openclose_args =
1167 &part->local_openclose_args[ch_number];
1169 atomic_set(&ch->kthreads_assigned, 0);
1170 atomic_set(&ch->kthreads_idle, 0);
1171 atomic_set(&ch->kthreads_active, 0);
1173 atomic_set(&ch->references, 0);
1174 atomic_set(&ch->n_to_notify, 0);
1176 spin_lock_init(&ch->lock);
1177 mutex_init(&ch->sn.sn2.msg_to_pull_mutex);
1178 init_completion(&ch->wdisconnect_wait);
1180 atomic_set(&ch->n_on_msg_allocate_wq, 0);
1181 init_waitqueue_head(&ch->msg_allocate_wq);
1182 init_waitqueue_head(&ch->idle_wq);
1186 * With the setting of the partition setup_state to XPC_P_SETUP, we're
1187 * declaring that this partition is ready to go.
1189 part->setup_state = XPC_P_SETUP;
1192 * Setup the per partition specific variables required by the
1193 * remote partition to establish channel connections with us.
1195 * The setting of the magic # indicates that these per partition
1196 * specific variables are ready to be used.
1198 xpc_vars_part[partid].GPs_pa = __pa(part_sn2->local_GPs);
1199 xpc_vars_part[partid].openclose_args_pa =
1200 __pa(part->local_openclose_args);
1201 xpc_vars_part[partid].chctl_amo_pa = __pa(part_sn2->local_chctl_amo_va);
1202 cpuid = raw_smp_processor_id(); /* any CPU in this partition will do */
1203 xpc_vars_part[partid].notify_IRQ_nasid = cpuid_to_nasid(cpuid);
1204 xpc_vars_part[partid].notify_IRQ_phys_cpuid = cpu_physical_id(cpuid);
1205 xpc_vars_part[partid].nchannels = part->nchannels;
1206 xpc_vars_part[partid].magic = XPC_VP_MAGIC1;
1208 return xpSuccess;
1210 /* setup of infrastructure failed */
1211 out_5:
1212 kfree(part->remote_openclose_args_base);
1213 part->remote_openclose_args = NULL;
1214 out_4:
1215 kfree(part->local_openclose_args_base);
1216 part->local_openclose_args = NULL;
1217 out_3:
1218 kfree(part_sn2->remote_GPs_base);
1219 part_sn2->remote_GPs = NULL;
1220 out_2:
1221 kfree(part_sn2->local_GPs_base);
1222 part_sn2->local_GPs = NULL;
1223 out_1:
1224 kfree(part->channels);
1225 part->channels = NULL;
1226 return retval;
1230 * Teardown the infrastructure necessary to support XPartition Communication
1231 * between the specified remote partition and the local one.
1233 static void
1234 xpc_teardown_infrastructure_sn2(struct xpc_partition *part)
1236 struct xpc_partition_sn2 *part_sn2 = &part->sn.sn2;
1237 short partid = XPC_PARTID(part);
1240 * We start off by making this partition inaccessible to local
1241 * processes by marking it as no longer setup. Then we make it
1242 * inaccessible to remote processes by clearing the XPC per partition
1243 * specific variable's magic # (which indicates that these variables
1244 * are no longer valid) and by ignoring all XPC notify IRQs sent to
1245 * this partition.
1248 DBUG_ON(atomic_read(&part->nchannels_engaged) != 0);
1249 DBUG_ON(atomic_read(&part->nchannels_active) != 0);
1250 DBUG_ON(part->setup_state != XPC_P_SETUP);
1251 part->setup_state = XPC_P_WTEARDOWN;
1253 xpc_vars_part[partid].magic = 0;
1255 free_irq(SGI_XPC_NOTIFY, (void *)(u64)partid);
1258 * Before proceeding with the teardown we have to wait until all
1259 * existing references cease.
1261 wait_event(part->teardown_wq, (atomic_read(&part->references) == 0));
1263 /* now we can begin tearing down the infrastructure */
1265 part->setup_state = XPC_P_TORNDOWN;
1267 /* in case we've still got outstanding timers registered... */
1268 del_timer_sync(&part_sn2->dropped_notify_IRQ_timer);
1270 kfree(part->remote_openclose_args_base);
1271 part->remote_openclose_args = NULL;
1272 kfree(part->local_openclose_args_base);
1273 part->local_openclose_args = NULL;
1274 kfree(part_sn2->remote_GPs_base);
1275 part_sn2->remote_GPs = NULL;
1276 kfree(part_sn2->local_GPs_base);
1277 part_sn2->local_GPs = NULL;
1278 kfree(part->channels);
1279 part->channels = NULL;
1280 part_sn2->local_chctl_amo_va = NULL;
1284 * Create a wrapper that hides the underlying mechanism for pulling a cacheline
1285 * (or multiple cachelines) from a remote partition.
1287 * src must be a cacheline aligned physical address on the remote partition.
1288 * dst must be a cacheline aligned virtual address on this partition.
1289 * cnt must be cacheline sized
1291 /* >>> Replace this function by call to xp_remote_memcpy() or bte_copy()? */
1292 static enum xp_retval
1293 xpc_pull_remote_cachelines_sn2(struct xpc_partition *part, void *dst,
1294 const void *src, size_t cnt)
1296 enum xp_retval ret;
1298 DBUG_ON((u64)src != L1_CACHE_ALIGN((u64)src));
1299 DBUG_ON((u64)dst != L1_CACHE_ALIGN((u64)dst));
1300 DBUG_ON(cnt != L1_CACHE_ALIGN(cnt));
1302 if (part->act_state == XPC_P_DEACTIVATING)
1303 return part->reason;
1305 ret = xp_remote_memcpy(dst, src, cnt);
1306 if (ret != xpSuccess) {
1307 dev_dbg(xpc_chan, "xp_remote_memcpy() from partition %d failed,"
1308 " ret=%d\n", XPC_PARTID(part), ret);
1310 return ret;
1314 * Pull the remote per partition specific variables from the specified
1315 * partition.
1317 static enum xp_retval
1318 xpc_pull_remote_vars_part_sn2(struct xpc_partition *part)
1320 struct xpc_partition_sn2 *part_sn2 = &part->sn.sn2;
1321 u8 buffer[L1_CACHE_BYTES * 2];
1322 struct xpc_vars_part_sn2 *pulled_entry_cacheline =
1323 (struct xpc_vars_part_sn2 *)L1_CACHE_ALIGN((u64)buffer);
1324 struct xpc_vars_part_sn2 *pulled_entry;
1325 u64 remote_entry_cacheline_pa, remote_entry_pa;
1326 short partid = XPC_PARTID(part);
1327 enum xp_retval ret;
1329 /* pull the cacheline that contains the variables we're interested in */
1331 DBUG_ON(part_sn2->remote_vars_part_pa !=
1332 L1_CACHE_ALIGN(part_sn2->remote_vars_part_pa));
1333 DBUG_ON(sizeof(struct xpc_vars_part_sn2) != L1_CACHE_BYTES / 2);
1335 remote_entry_pa = part_sn2->remote_vars_part_pa +
1336 sn_partition_id * sizeof(struct xpc_vars_part_sn2);
1338 remote_entry_cacheline_pa = (remote_entry_pa & ~(L1_CACHE_BYTES - 1));
1340 pulled_entry = (struct xpc_vars_part_sn2 *)((u64)pulled_entry_cacheline
1341 + (remote_entry_pa &
1342 (L1_CACHE_BYTES - 1)));
1344 ret = xpc_pull_remote_cachelines_sn2(part, pulled_entry_cacheline,
1345 (void *)remote_entry_cacheline_pa,
1346 L1_CACHE_BYTES);
1347 if (ret != xpSuccess) {
1348 dev_dbg(xpc_chan, "failed to pull XPC vars_part from "
1349 "partition %d, ret=%d\n", partid, ret);
1350 return ret;
1353 /* see if they've been set up yet */
1355 if (pulled_entry->magic != XPC_VP_MAGIC1 &&
1356 pulled_entry->magic != XPC_VP_MAGIC2) {
1358 if (pulled_entry->magic != 0) {
1359 dev_dbg(xpc_chan, "partition %d's XPC vars_part for "
1360 "partition %d has bad magic value (=0x%lx)\n",
1361 partid, sn_partition_id, pulled_entry->magic);
1362 return xpBadMagic;
1365 /* they've not been initialized yet */
1366 return xpRetry;
1369 if (xpc_vars_part[partid].magic == XPC_VP_MAGIC1) {
1371 /* validate the variables */
1373 if (pulled_entry->GPs_pa == 0 ||
1374 pulled_entry->openclose_args_pa == 0 ||
1375 pulled_entry->chctl_amo_pa == 0) {
1377 dev_err(xpc_chan, "partition %d's XPC vars_part for "
1378 "partition %d are not valid\n", partid,
1379 sn_partition_id);
1380 return xpInvalidAddress;
1383 /* the variables we imported look to be valid */
1385 part_sn2->remote_GPs_pa = pulled_entry->GPs_pa;
1386 part_sn2->remote_openclose_args_pa =
1387 pulled_entry->openclose_args_pa;
1388 part_sn2->remote_chctl_amo_va =
1389 (AMO_t *)__va(pulled_entry->chctl_amo_pa);
1390 part_sn2->notify_IRQ_nasid = pulled_entry->notify_IRQ_nasid;
1391 part_sn2->notify_IRQ_phys_cpuid =
1392 pulled_entry->notify_IRQ_phys_cpuid;
1394 if (part->nchannels > pulled_entry->nchannels)
1395 part->nchannels = pulled_entry->nchannels;
1397 /* let the other side know that we've pulled their variables */
1399 xpc_vars_part[partid].magic = XPC_VP_MAGIC2;
1402 if (pulled_entry->magic == XPC_VP_MAGIC1)
1403 return xpRetry;
1405 return xpSuccess;
1409 * Establish first contact with the remote partititon. This involves pulling
1410 * the XPC per partition variables from the remote partition and waiting for
1411 * the remote partition to pull ours.
1413 static enum xp_retval
1414 xpc_make_first_contact_sn2(struct xpc_partition *part)
1416 struct xpc_partition_sn2 *part_sn2 = &part->sn.sn2;
1417 enum xp_retval ret;
1420 * Register the remote partition's AMOs with SAL so it can handle
1421 * and cleanup errors within that address range should the remote
1422 * partition go down. We don't unregister this range because it is
1423 * difficult to tell when outstanding writes to the remote partition
1424 * are finished and thus when it is safe to unregister. This should
1425 * not result in wasted space in the SAL xp_addr_region table because
1426 * we should get the same page for remote_amos_page_pa after module
1427 * reloads and system reboots.
1429 if (sn_register_xp_addr_region(part_sn2->remote_amos_page_pa,
1430 PAGE_SIZE, 1) < 0) {
1431 dev_warn(xpc_part, "xpc_activating(%d) failed to register "
1432 "xp_addr region\n", XPC_PARTID(part));
1434 ret = xpPhysAddrRegFailed;
1435 XPC_DEACTIVATE_PARTITION(part, ret);
1436 return ret;
1440 * Send activate IRQ to get other side to activate if they've not
1441 * already begun to do so.
1443 xpc_send_activate_IRQ_sn2(part_sn2->remote_amos_page_pa,
1444 cnodeid_to_nasid(0),
1445 part_sn2->activate_IRQ_nasid,
1446 part_sn2->activate_IRQ_phys_cpuid);
1448 while ((ret = xpc_pull_remote_vars_part_sn2(part)) != xpSuccess) {
1449 if (ret != xpRetry) {
1450 XPC_DEACTIVATE_PARTITION(part, ret);
1451 return ret;
1454 dev_dbg(xpc_part, "waiting to make first contact with "
1455 "partition %d\n", XPC_PARTID(part));
1457 /* wait a 1/4 of a second or so */
1458 (void)msleep_interruptible(250);
1460 if (part->act_state == XPC_P_DEACTIVATING)
1461 return part->reason;
1464 return xpSuccess;
1468 * Get the chctl flags and pull the openclose args and/or remote GPs as needed.
1470 static u64
1471 xpc_get_chctl_all_flags_sn2(struct xpc_partition *part)
1473 struct xpc_partition_sn2 *part_sn2 = &part->sn.sn2;
1474 unsigned long irq_flags;
1475 union xpc_channel_ctl_flags chctl;
1476 enum xp_retval ret;
1479 * See if there are any chctl flags to be handled.
1482 spin_lock_irqsave(&part->chctl_lock, irq_flags);
1483 chctl = part->chctl;
1484 if (chctl.all_flags != 0)
1485 part->chctl.all_flags = 0;
1487 spin_unlock_irqrestore(&part->chctl_lock, irq_flags);
1489 if (xpc_any_openclose_chctl_flags_set(&chctl)) {
1490 ret = xpc_pull_remote_cachelines_sn2(part, part->
1491 remote_openclose_args,
1492 (void *)part_sn2->
1493 remote_openclose_args_pa,
1494 XPC_OPENCLOSE_ARGS_SIZE);
1495 if (ret != xpSuccess) {
1496 XPC_DEACTIVATE_PARTITION(part, ret);
1498 dev_dbg(xpc_chan, "failed to pull openclose args from "
1499 "partition %d, ret=%d\n", XPC_PARTID(part),
1500 ret);
1502 /* don't bother processing chctl flags anymore */
1503 chctl.all_flags = 0;
1507 if (xpc_any_msg_chctl_flags_set(&chctl)) {
1508 ret = xpc_pull_remote_cachelines_sn2(part, part_sn2->remote_GPs,
1509 (void *)part_sn2->remote_GPs_pa,
1510 XPC_GP_SIZE);
1511 if (ret != xpSuccess) {
1512 XPC_DEACTIVATE_PARTITION(part, ret);
1514 dev_dbg(xpc_chan, "failed to pull GPs from partition "
1515 "%d, ret=%d\n", XPC_PARTID(part), ret);
1517 /* don't bother processing chctl flags anymore */
1518 chctl.all_flags = 0;
1522 return chctl.all_flags;
1526 * Notify those who wanted to be notified upon delivery of their message.
1528 static void
1529 xpc_notify_senders_sn2(struct xpc_channel *ch, enum xp_retval reason, s64 put)
1531 struct xpc_notify *notify;
1532 u8 notify_type;
1533 s64 get = ch->sn.sn2.w_remote_GP.get - 1;
1535 while (++get < put && atomic_read(&ch->n_to_notify) > 0) {
1537 notify = &ch->notify_queue[get % ch->local_nentries];
1540 * See if the notify entry indicates it was associated with
1541 * a message who's sender wants to be notified. It is possible
1542 * that it is, but someone else is doing or has done the
1543 * notification.
1545 notify_type = notify->type;
1546 if (notify_type == 0 ||
1547 cmpxchg(&notify->type, notify_type, 0) != notify_type) {
1548 continue;
1551 DBUG_ON(notify_type != XPC_N_CALL);
1553 atomic_dec(&ch->n_to_notify);
1555 if (notify->func != NULL) {
1556 dev_dbg(xpc_chan, "notify->func() called, notify=0x%p, "
1557 "msg_number=%ld, partid=%d, channel=%d\n",
1558 (void *)notify, get, ch->partid, ch->number);
1560 notify->func(reason, ch->partid, ch->number,
1561 notify->key);
1563 dev_dbg(xpc_chan, "notify->func() returned, "
1564 "notify=0x%p, msg_number=%ld, partid=%d, "
1565 "channel=%d\n", (void *)notify, get,
1566 ch->partid, ch->number);
1571 static void
1572 xpc_notify_senders_of_disconnect_sn2(struct xpc_channel *ch)
1574 xpc_notify_senders_sn2(ch, ch->reason, ch->sn.sn2.w_local_GP.put);
1578 * Clear some of the msg flags in the local message queue.
1580 static inline void
1581 xpc_clear_local_msgqueue_flags_sn2(struct xpc_channel *ch)
1583 struct xpc_channel_sn2 *ch_sn2 = &ch->sn.sn2;
1584 struct xpc_msg *msg;
1585 s64 get;
1587 get = ch_sn2->w_remote_GP.get;
1588 do {
1589 msg = (struct xpc_msg *)((u64)ch->local_msgqueue +
1590 (get % ch->local_nentries) *
1591 ch->msg_size);
1592 msg->flags = 0;
1593 } while (++get < ch_sn2->remote_GP.get);
1597 * Clear some of the msg flags in the remote message queue.
1599 static inline void
1600 xpc_clear_remote_msgqueue_flags_sn2(struct xpc_channel *ch)
1602 struct xpc_channel_sn2 *ch_sn2 = &ch->sn.sn2;
1603 struct xpc_msg *msg;
1604 s64 put;
1606 put = ch_sn2->w_remote_GP.put;
1607 do {
1608 msg = (struct xpc_msg *)((u64)ch->remote_msgqueue +
1609 (put % ch->remote_nentries) *
1610 ch->msg_size);
1611 msg->flags = 0;
1612 } while (++put < ch_sn2->remote_GP.put);
1615 static void
1616 xpc_process_msg_chctl_flags_sn2(struct xpc_partition *part, int ch_number)
1618 struct xpc_channel *ch = &part->channels[ch_number];
1619 struct xpc_channel_sn2 *ch_sn2 = &ch->sn.sn2;
1620 int nmsgs_sent;
1622 ch_sn2->remote_GP = part->sn.sn2.remote_GPs[ch_number];
1624 /* See what, if anything, has changed for each connected channel */
1626 xpc_msgqueue_ref(ch);
1628 if (ch_sn2->w_remote_GP.get == ch_sn2->remote_GP.get &&
1629 ch_sn2->w_remote_GP.put == ch_sn2->remote_GP.put) {
1630 /* nothing changed since GPs were last pulled */
1631 xpc_msgqueue_deref(ch);
1632 return;
1635 if (!(ch->flags & XPC_C_CONNECTED)) {
1636 xpc_msgqueue_deref(ch);
1637 return;
1641 * First check to see if messages recently sent by us have been
1642 * received by the other side. (The remote GET value will have
1643 * changed since we last looked at it.)
1646 if (ch_sn2->w_remote_GP.get != ch_sn2->remote_GP.get) {
1649 * We need to notify any senders that want to be notified
1650 * that their sent messages have been received by their
1651 * intended recipients. We need to do this before updating
1652 * w_remote_GP.get so that we don't allocate the same message
1653 * queue entries prematurely (see xpc_allocate_msg()).
1655 if (atomic_read(&ch->n_to_notify) > 0) {
1657 * Notify senders that messages sent have been
1658 * received and delivered by the other side.
1660 xpc_notify_senders_sn2(ch, xpMsgDelivered,
1661 ch_sn2->remote_GP.get);
1665 * Clear msg->flags in previously sent messages, so that
1666 * they're ready for xpc_allocate_msg().
1668 xpc_clear_local_msgqueue_flags_sn2(ch);
1670 ch_sn2->w_remote_GP.get = ch_sn2->remote_GP.get;
1672 dev_dbg(xpc_chan, "w_remote_GP.get changed to %ld, partid=%d, "
1673 "channel=%d\n", ch_sn2->w_remote_GP.get, ch->partid,
1674 ch->number);
1677 * If anyone was waiting for message queue entries to become
1678 * available, wake them up.
1680 if (atomic_read(&ch->n_on_msg_allocate_wq) > 0)
1681 wake_up(&ch->msg_allocate_wq);
1685 * Now check for newly sent messages by the other side. (The remote
1686 * PUT value will have changed since we last looked at it.)
1689 if (ch_sn2->w_remote_GP.put != ch_sn2->remote_GP.put) {
1691 * Clear msg->flags in previously received messages, so that
1692 * they're ready for xpc_get_deliverable_msg().
1694 xpc_clear_remote_msgqueue_flags_sn2(ch);
1696 ch_sn2->w_remote_GP.put = ch_sn2->remote_GP.put;
1698 dev_dbg(xpc_chan, "w_remote_GP.put changed to %ld, partid=%d, "
1699 "channel=%d\n", ch_sn2->w_remote_GP.put, ch->partid,
1700 ch->number);
1702 nmsgs_sent = ch_sn2->w_remote_GP.put - ch_sn2->w_local_GP.get;
1703 if (nmsgs_sent > 0) {
1704 dev_dbg(xpc_chan, "msgs waiting to be copied and "
1705 "delivered=%d, partid=%d, channel=%d\n",
1706 nmsgs_sent, ch->partid, ch->number);
1708 if (ch->flags & XPC_C_CONNECTEDCALLOUT_MADE)
1709 xpc_activate_kthreads(ch, nmsgs_sent);
1713 xpc_msgqueue_deref(ch);
1716 static struct xpc_msg *
1717 xpc_pull_remote_msg_sn2(struct xpc_channel *ch, s64 get)
1719 struct xpc_partition *part = &xpc_partitions[ch->partid];
1720 struct xpc_channel_sn2 *ch_sn2 = &ch->sn.sn2;
1721 struct xpc_msg *remote_msg, *msg;
1722 u32 msg_index, nmsgs;
1723 u64 msg_offset;
1724 enum xp_retval ret;
1726 if (mutex_lock_interruptible(&ch_sn2->msg_to_pull_mutex) != 0) {
1727 /* we were interrupted by a signal */
1728 return NULL;
1731 while (get >= ch_sn2->next_msg_to_pull) {
1733 /* pull as many messages as are ready and able to be pulled */
1735 msg_index = ch_sn2->next_msg_to_pull % ch->remote_nentries;
1737 DBUG_ON(ch_sn2->next_msg_to_pull >= ch_sn2->w_remote_GP.put);
1738 nmsgs = ch_sn2->w_remote_GP.put - ch_sn2->next_msg_to_pull;
1739 if (msg_index + nmsgs > ch->remote_nentries) {
1740 /* ignore the ones that wrap the msg queue for now */
1741 nmsgs = ch->remote_nentries - msg_index;
1744 msg_offset = msg_index * ch->msg_size;
1745 msg = (struct xpc_msg *)((u64)ch->remote_msgqueue + msg_offset);
1746 remote_msg = (struct xpc_msg *)(ch->remote_msgqueue_pa +
1747 msg_offset);
1749 ret = xpc_pull_remote_cachelines_sn2(part, msg, remote_msg,
1750 nmsgs * ch->msg_size);
1751 if (ret != xpSuccess) {
1753 dev_dbg(xpc_chan, "failed to pull %d msgs starting with"
1754 " msg %ld from partition %d, channel=%d, "
1755 "ret=%d\n", nmsgs, ch_sn2->next_msg_to_pull,
1756 ch->partid, ch->number, ret);
1758 XPC_DEACTIVATE_PARTITION(part, ret);
1760 mutex_unlock(&ch_sn2->msg_to_pull_mutex);
1761 return NULL;
1764 ch_sn2->next_msg_to_pull += nmsgs;
1767 mutex_unlock(&ch_sn2->msg_to_pull_mutex);
1769 /* return the message we were looking for */
1770 msg_offset = (get % ch->remote_nentries) * ch->msg_size;
1771 msg = (struct xpc_msg *)((u64)ch->remote_msgqueue + msg_offset);
1773 return msg;
1776 static int
1777 xpc_n_of_deliverable_msgs_sn2(struct xpc_channel *ch)
1779 return ch->sn.sn2.w_remote_GP.put - ch->sn.sn2.w_local_GP.get;
1783 * Get a message to be delivered.
1785 static struct xpc_msg *
1786 xpc_get_deliverable_msg_sn2(struct xpc_channel *ch)
1788 struct xpc_channel_sn2 *ch_sn2 = &ch->sn.sn2;
1789 struct xpc_msg *msg = NULL;
1790 s64 get;
1792 do {
1793 if (ch->flags & XPC_C_DISCONNECTING)
1794 break;
1796 get = ch_sn2->w_local_GP.get;
1797 rmb(); /* guarantee that .get loads before .put */
1798 if (get == ch_sn2->w_remote_GP.put)
1799 break;
1801 /* There are messages waiting to be pulled and delivered.
1802 * We need to try to secure one for ourselves. We'll do this
1803 * by trying to increment w_local_GP.get and hope that no one
1804 * else beats us to it. If they do, we'll we'll simply have
1805 * to try again for the next one.
1808 if (cmpxchg(&ch_sn2->w_local_GP.get, get, get + 1) == get) {
1809 /* we got the entry referenced by get */
1811 dev_dbg(xpc_chan, "w_local_GP.get changed to %ld, "
1812 "partid=%d, channel=%d\n", get + 1,
1813 ch->partid, ch->number);
1815 /* pull the message from the remote partition */
1817 msg = xpc_pull_remote_msg_sn2(ch, get);
1819 DBUG_ON(msg != NULL && msg->number != get);
1820 DBUG_ON(msg != NULL && (msg->flags & XPC_M_DONE));
1821 DBUG_ON(msg != NULL && !(msg->flags & XPC_M_READY));
1823 break;
1826 } while (1);
1828 return msg;
1832 * Now we actually send the messages that are ready to be sent by advancing
1833 * the local message queue's Put value and then send a chctl msgrequest to the
1834 * recipient partition.
1836 static void
1837 xpc_send_msgs_sn2(struct xpc_channel *ch, s64 initial_put)
1839 struct xpc_channel_sn2 *ch_sn2 = &ch->sn.sn2;
1840 struct xpc_msg *msg;
1841 s64 put = initial_put + 1;
1842 int send_msgrequest = 0;
1844 while (1) {
1846 while (1) {
1847 if (put == ch_sn2->w_local_GP.put)
1848 break;
1850 msg = (struct xpc_msg *)((u64)ch->local_msgqueue +
1851 (put % ch->local_nentries) *
1852 ch->msg_size);
1854 if (!(msg->flags & XPC_M_READY))
1855 break;
1857 put++;
1860 if (put == initial_put) {
1861 /* nothing's changed */
1862 break;
1865 if (cmpxchg_rel(&ch_sn2->local_GP->put, initial_put, put) !=
1866 initial_put) {
1867 /* someone else beat us to it */
1868 DBUG_ON(ch_sn2->local_GP->put < initial_put);
1869 break;
1872 /* we just set the new value of local_GP->put */
1874 dev_dbg(xpc_chan, "local_GP->put changed to %ld, partid=%d, "
1875 "channel=%d\n", put, ch->partid, ch->number);
1877 send_msgrequest = 1;
1880 * We need to ensure that the message referenced by
1881 * local_GP->put is not XPC_M_READY or that local_GP->put
1882 * equals w_local_GP.put, so we'll go have a look.
1884 initial_put = put;
1887 if (send_msgrequest)
1888 xpc_send_chctl_msgrequest_sn2(ch);
1892 * Allocate an entry for a message from the message queue associated with the
1893 * specified channel.
1895 static enum xp_retval
1896 xpc_allocate_msg_sn2(struct xpc_channel *ch, u32 flags,
1897 struct xpc_msg **address_of_msg)
1899 struct xpc_channel_sn2 *ch_sn2 = &ch->sn.sn2;
1900 struct xpc_msg *msg;
1901 enum xp_retval ret;
1902 s64 put;
1905 * Get the next available message entry from the local message queue.
1906 * If none are available, we'll make sure that we grab the latest
1907 * GP values.
1909 ret = xpTimeout;
1911 while (1) {
1913 put = ch_sn2->w_local_GP.put;
1914 rmb(); /* guarantee that .put loads before .get */
1915 if (put - ch_sn2->w_remote_GP.get < ch->local_nentries) {
1917 /* There are available message entries. We need to try
1918 * to secure one for ourselves. We'll do this by trying
1919 * to increment w_local_GP.put as long as someone else
1920 * doesn't beat us to it. If they do, we'll have to
1921 * try again.
1923 if (cmpxchg(&ch_sn2->w_local_GP.put, put, put + 1) ==
1924 put) {
1925 /* we got the entry referenced by put */
1926 break;
1928 continue; /* try again */
1932 * There aren't any available msg entries at this time.
1934 * In waiting for a message entry to become available,
1935 * we set a timeout in case the other side is not sending
1936 * completion interrupts. This lets us fake a notify IRQ
1937 * that will cause the notify IRQ handler to fetch the latest
1938 * GP values as if an interrupt was sent by the other side.
1940 if (ret == xpTimeout)
1941 xpc_send_chctl_local_msgrequest_sn2(ch);
1943 if (flags & XPC_NOWAIT)
1944 return xpNoWait;
1946 ret = xpc_allocate_msg_wait(ch);
1947 if (ret != xpInterrupted && ret != xpTimeout)
1948 return ret;
1951 /* get the message's address and initialize it */
1952 msg = (struct xpc_msg *)((u64)ch->local_msgqueue +
1953 (put % ch->local_nentries) * ch->msg_size);
1955 DBUG_ON(msg->flags != 0);
1956 msg->number = put;
1958 dev_dbg(xpc_chan, "w_local_GP.put changed to %ld; msg=0x%p, "
1959 "msg_number=%ld, partid=%d, channel=%d\n", put + 1,
1960 (void *)msg, msg->number, ch->partid, ch->number);
1962 *address_of_msg = msg;
1963 return xpSuccess;
1967 * Common code that does the actual sending of the message by advancing the
1968 * local message queue's Put value and sends a chctl msgrequest to the
1969 * partition the message is being sent to.
1971 static enum xp_retval
1972 xpc_send_msg_sn2(struct xpc_channel *ch, u32 flags, void *payload,
1973 u16 payload_size, u8 notify_type, xpc_notify_func func,
1974 void *key)
1976 enum xp_retval ret = xpSuccess;
1977 struct xpc_msg *msg = msg;
1978 struct xpc_notify *notify = notify;
1979 s64 msg_number;
1980 s64 put;
1982 DBUG_ON(notify_type == XPC_N_CALL && func == NULL);
1984 if (XPC_MSG_SIZE(payload_size) > ch->msg_size)
1985 return xpPayloadTooBig;
1987 xpc_msgqueue_ref(ch);
1989 if (ch->flags & XPC_C_DISCONNECTING) {
1990 ret = ch->reason;
1991 goto out_1;
1993 if (!(ch->flags & XPC_C_CONNECTED)) {
1994 ret = xpNotConnected;
1995 goto out_1;
1998 ret = xpc_allocate_msg_sn2(ch, flags, &msg);
1999 if (ret != xpSuccess)
2000 goto out_1;
2002 msg_number = msg->number;
2004 if (notify_type != 0) {
2006 * Tell the remote side to send an ACK interrupt when the
2007 * message has been delivered.
2009 msg->flags |= XPC_M_INTERRUPT;
2011 atomic_inc(&ch->n_to_notify);
2013 notify = &ch->notify_queue[msg_number % ch->local_nentries];
2014 notify->func = func;
2015 notify->key = key;
2016 notify->type = notify_type;
2018 /* >>> is a mb() needed here? */
2020 if (ch->flags & XPC_C_DISCONNECTING) {
2022 * An error occurred between our last error check and
2023 * this one. We will try to clear the type field from
2024 * the notify entry. If we succeed then
2025 * xpc_disconnect_channel() didn't already process
2026 * the notify entry.
2028 if (cmpxchg(&notify->type, notify_type, 0) ==
2029 notify_type) {
2030 atomic_dec(&ch->n_to_notify);
2031 ret = ch->reason;
2033 goto out_1;
2037 memcpy(&msg->payload, payload, payload_size);
2039 msg->flags |= XPC_M_READY;
2042 * The preceding store of msg->flags must occur before the following
2043 * load of local_GP->put.
2045 mb();
2047 /* see if the message is next in line to be sent, if so send it */
2049 put = ch->sn.sn2.local_GP->put;
2050 if (put == msg_number)
2051 xpc_send_msgs_sn2(ch, put);
2053 out_1:
2054 xpc_msgqueue_deref(ch);
2055 return ret;
2059 * Now we actually acknowledge the messages that have been delivered and ack'd
2060 * by advancing the cached remote message queue's Get value and if requested
2061 * send a chctl msgrequest to the message sender's partition.
2063 static void
2064 xpc_acknowledge_msgs_sn2(struct xpc_channel *ch, s64 initial_get, u8 msg_flags)
2066 struct xpc_channel_sn2 *ch_sn2 = &ch->sn.sn2;
2067 struct xpc_msg *msg;
2068 s64 get = initial_get + 1;
2069 int send_msgrequest = 0;
2071 while (1) {
2073 while (1) {
2074 if (get == ch_sn2->w_local_GP.get)
2075 break;
2077 msg = (struct xpc_msg *)((u64)ch->remote_msgqueue +
2078 (get % ch->remote_nentries) *
2079 ch->msg_size);
2081 if (!(msg->flags & XPC_M_DONE))
2082 break;
2084 msg_flags |= msg->flags;
2085 get++;
2088 if (get == initial_get) {
2089 /* nothing's changed */
2090 break;
2093 if (cmpxchg_rel(&ch_sn2->local_GP->get, initial_get, get) !=
2094 initial_get) {
2095 /* someone else beat us to it */
2096 DBUG_ON(ch_sn2->local_GP->get <= initial_get);
2097 break;
2100 /* we just set the new value of local_GP->get */
2102 dev_dbg(xpc_chan, "local_GP->get changed to %ld, partid=%d, "
2103 "channel=%d\n", get, ch->partid, ch->number);
2105 send_msgrequest = (msg_flags & XPC_M_INTERRUPT);
2108 * We need to ensure that the message referenced by
2109 * local_GP->get is not XPC_M_DONE or that local_GP->get
2110 * equals w_local_GP.get, so we'll go have a look.
2112 initial_get = get;
2115 if (send_msgrequest)
2116 xpc_send_chctl_msgrequest_sn2(ch);
2119 static void
2120 xpc_received_msg_sn2(struct xpc_channel *ch, struct xpc_msg *msg)
2122 s64 get;
2123 s64 msg_number = msg->number;
2125 dev_dbg(xpc_chan, "msg=0x%p, msg_number=%ld, partid=%d, channel=%d\n",
2126 (void *)msg, msg_number, ch->partid, ch->number);
2128 DBUG_ON((((u64)msg - (u64)ch->remote_msgqueue) / ch->msg_size) !=
2129 msg_number % ch->remote_nentries);
2130 DBUG_ON(msg->flags & XPC_M_DONE);
2132 msg->flags |= XPC_M_DONE;
2135 * The preceding store of msg->flags must occur before the following
2136 * load of local_GP->get.
2138 mb();
2141 * See if this message is next in line to be acknowledged as having
2142 * been delivered.
2144 get = ch->sn.sn2.local_GP->get;
2145 if (get == msg_number)
2146 xpc_acknowledge_msgs_sn2(ch, get, msg->flags);
2150 xpc_init_sn2(void)
2152 int ret;
2154 xpc_rsvd_page_init = xpc_rsvd_page_init_sn2;
2155 xpc_increment_heartbeat = xpc_increment_heartbeat_sn2;
2156 xpc_offline_heartbeat = xpc_offline_heartbeat_sn2;
2157 xpc_online_heartbeat = xpc_online_heartbeat_sn2;
2158 xpc_heartbeat_init = xpc_heartbeat_init_sn2;
2159 xpc_heartbeat_exit = xpc_heartbeat_exit_sn2;
2160 xpc_check_remote_hb = xpc_check_remote_hb_sn2;
2162 xpc_request_partition_activation = xpc_request_partition_activation_sn2;
2163 xpc_request_partition_reactivation =
2164 xpc_request_partition_reactivation_sn2;
2165 xpc_request_partition_deactivation =
2166 xpc_request_partition_deactivation_sn2;
2167 xpc_cancel_partition_deactivation_request =
2168 xpc_cancel_partition_deactivation_request_sn2;
2170 xpc_process_activate_IRQ_rcvd = xpc_process_activate_IRQ_rcvd_sn2;
2171 xpc_setup_infrastructure = xpc_setup_infrastructure_sn2;
2172 xpc_teardown_infrastructure = xpc_teardown_infrastructure_sn2;
2173 xpc_make_first_contact = xpc_make_first_contact_sn2;
2174 xpc_get_chctl_all_flags = xpc_get_chctl_all_flags_sn2;
2175 xpc_notify_senders_of_disconnect = xpc_notify_senders_of_disconnect_sn2;
2176 xpc_process_msg_chctl_flags = xpc_process_msg_chctl_flags_sn2;
2177 xpc_n_of_deliverable_msgs = xpc_n_of_deliverable_msgs_sn2;
2178 xpc_get_deliverable_msg = xpc_get_deliverable_msg_sn2;
2180 xpc_indicate_partition_engaged = xpc_indicate_partition_engaged_sn2;
2181 xpc_partition_engaged = xpc_partition_engaged_sn2;
2182 xpc_any_partition_engaged = xpc_any_partition_engaged_sn2;
2183 xpc_indicate_partition_disengaged =
2184 xpc_indicate_partition_disengaged_sn2;
2185 xpc_assume_partition_disengaged = xpc_assume_partition_disengaged_sn2;
2187 xpc_send_chctl_closerequest = xpc_send_chctl_closerequest_sn2;
2188 xpc_send_chctl_closereply = xpc_send_chctl_closereply_sn2;
2189 xpc_send_chctl_openrequest = xpc_send_chctl_openrequest_sn2;
2190 xpc_send_chctl_openreply = xpc_send_chctl_openreply_sn2;
2192 xpc_send_msg = xpc_send_msg_sn2;
2193 xpc_received_msg = xpc_received_msg_sn2;
2195 /* open up protections for IPI and [potentially] AMO operations */
2196 xpc_allow_IPI_ops_sn2();
2197 xpc_allow_AMO_ops_shub_wars_1_1_sn2();
2200 * This is safe to do before the xpc_hb_checker thread has started
2201 * because the handler releases a wait queue. If an interrupt is
2202 * received before the thread is waiting, it will not go to sleep,
2203 * but rather immediately process the interrupt.
2205 ret = request_irq(SGI_XPC_ACTIVATE, xpc_handle_activate_IRQ_sn2, 0,
2206 "xpc hb", NULL);
2207 if (ret != 0) {
2208 dev_err(xpc_part, "can't register ACTIVATE IRQ handler, "
2209 "errno=%d\n", -ret);
2210 xpc_disallow_IPI_ops_sn2();
2212 return ret;
2215 void
2216 xpc_exit_sn2(void)
2218 free_irq(SGI_XPC_ACTIVATE, NULL);
2219 xpc_disallow_IPI_ops_sn2();