ARM: 6214/2: driver for the character LCD found in ARM refdesigns
[linux-2.6.git] / drivers / misc / sgi-xp / xpc_sn2.c
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.
5  *
6  * Copyright (c) 2008-2009 Silicon Graphics, Inc.  All Rights Reserved.
7  */
8
9 /*
10  * Cross Partition Communication (XPC) sn2-based functions.
11  *
12  *     Architecture specific implementation of common functions.
13  *
14  */
15
16 #include <linux/delay.h>
17 #include <linux/slab.h>
18 #include <asm/uncached.h>
19 #include <asm/sn/mspec.h>
20 #include <asm/sn/sn_sal.h>
21 #include "xpc.h"
22
23 /*
24  * Define the number of u64s required to represent all the C-brick nasids
25  * as a bitmap.  The cross-partition kernel modules deal only with
26  * C-brick nasids, thus the need for bitmaps which don't account for
27  * odd-numbered (non C-brick) nasids.
28  */
29 #define XPC_MAX_PHYSNODES_SN2   (MAX_NUMALINK_NODES / 2)
30 #define XP_NASID_MASK_BYTES_SN2 ((XPC_MAX_PHYSNODES_SN2 + 7) / 8)
31 #define XP_NASID_MASK_WORDS_SN2 ((XPC_MAX_PHYSNODES_SN2 + 63) / 64)
32
33 /*
34  * Memory for XPC's amo variables is allocated by the MSPEC driver. These
35  * pages are located in the lowest granule. The lowest granule uses 4k pages
36  * for cached references and an alternate TLB handler to never provide a
37  * cacheable mapping for the entire region. This will prevent speculative
38  * reading of cached copies of our lines from being issued which will cause
39  * a PI FSB Protocol error to be generated by the SHUB. For XPC, we need 64
40  * amo variables (based on XP_MAX_NPARTITIONS_SN2) to identify the senders of
41  * NOTIFY IRQs, 128 amo variables (based on XP_NASID_MASK_WORDS_SN2) to identify
42  * the senders of ACTIVATE IRQs, 1 amo variable to identify which remote
43  * partitions (i.e., XPCs) consider themselves currently engaged with the
44  * local XPC and 1 amo variable to request partition deactivation.
45  */
46 #define XPC_NOTIFY_IRQ_AMOS_SN2         0
47 #define XPC_ACTIVATE_IRQ_AMOS_SN2       (XPC_NOTIFY_IRQ_AMOS_SN2 + \
48                                          XP_MAX_NPARTITIONS_SN2)
49 #define XPC_ENGAGED_PARTITIONS_AMO_SN2  (XPC_ACTIVATE_IRQ_AMOS_SN2 + \
50                                          XP_NASID_MASK_WORDS_SN2)
51 #define XPC_DEACTIVATE_REQUEST_AMO_SN2  (XPC_ENGAGED_PARTITIONS_AMO_SN2 + 1)
52
53 /*
54  * Buffer used to store a local copy of portions of a remote partition's
55  * reserved page (either its header and part_nasids mask, or its vars).
56  */
57 static void *xpc_remote_copy_buffer_base_sn2;
58 static char *xpc_remote_copy_buffer_sn2;
59
60 static struct xpc_vars_sn2 *xpc_vars_sn2;
61 static struct xpc_vars_part_sn2 *xpc_vars_part_sn2;
62
63 static int
64 xpc_setup_partitions_sn2(void)
65 {
66         /* nothing needs to be done */
67         return 0;
68 }
69
70 static void
71 xpc_teardown_partitions_sn2(void)
72 {
73         /* nothing needs to be done */
74 }
75
76 /* SH_IPI_ACCESS shub register value on startup */
77 static u64 xpc_sh1_IPI_access_sn2;
78 static u64 xpc_sh2_IPI_access0_sn2;
79 static u64 xpc_sh2_IPI_access1_sn2;
80 static u64 xpc_sh2_IPI_access2_sn2;
81 static u64 xpc_sh2_IPI_access3_sn2;
82
83 /*
84  * Change protections to allow IPI operations.
85  */
86 static void
87 xpc_allow_IPI_ops_sn2(void)
88 {
89         int node;
90         int nasid;
91
92         /* !!! The following should get moved into SAL. */
93         if (is_shub2()) {
94                 xpc_sh2_IPI_access0_sn2 =
95                     (u64)HUB_L((u64 *)LOCAL_MMR_ADDR(SH2_IPI_ACCESS0));
96                 xpc_sh2_IPI_access1_sn2 =
97                     (u64)HUB_L((u64 *)LOCAL_MMR_ADDR(SH2_IPI_ACCESS1));
98                 xpc_sh2_IPI_access2_sn2 =
99                     (u64)HUB_L((u64 *)LOCAL_MMR_ADDR(SH2_IPI_ACCESS2));
100                 xpc_sh2_IPI_access3_sn2 =
101                     (u64)HUB_L((u64 *)LOCAL_MMR_ADDR(SH2_IPI_ACCESS3));
102
103                 for_each_online_node(node) {
104                         nasid = cnodeid_to_nasid(node);
105                         HUB_S((u64 *)GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS0),
106                               -1UL);
107                         HUB_S((u64 *)GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS1),
108                               -1UL);
109                         HUB_S((u64 *)GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS2),
110                               -1UL);
111                         HUB_S((u64 *)GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS3),
112                               -1UL);
113                 }
114         } else {
115                 xpc_sh1_IPI_access_sn2 =
116                     (u64)HUB_L((u64 *)LOCAL_MMR_ADDR(SH1_IPI_ACCESS));
117
118                 for_each_online_node(node) {
119                         nasid = cnodeid_to_nasid(node);
120                         HUB_S((u64 *)GLOBAL_MMR_ADDR(nasid, SH1_IPI_ACCESS),
121                               -1UL);
122                 }
123         }
124 }
125
126 /*
127  * Restrict protections to disallow IPI operations.
128  */
129 static void
130 xpc_disallow_IPI_ops_sn2(void)
131 {
132         int node;
133         int nasid;
134
135         /* !!! The following should get moved into SAL. */
136         if (is_shub2()) {
137                 for_each_online_node(node) {
138                         nasid = cnodeid_to_nasid(node);
139                         HUB_S((u64 *)GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS0),
140                               xpc_sh2_IPI_access0_sn2);
141                         HUB_S((u64 *)GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS1),
142                               xpc_sh2_IPI_access1_sn2);
143                         HUB_S((u64 *)GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS2),
144                               xpc_sh2_IPI_access2_sn2);
145                         HUB_S((u64 *)GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS3),
146                               xpc_sh2_IPI_access3_sn2);
147                 }
148         } else {
149                 for_each_online_node(node) {
150                         nasid = cnodeid_to_nasid(node);
151                         HUB_S((u64 *)GLOBAL_MMR_ADDR(nasid, SH1_IPI_ACCESS),
152                               xpc_sh1_IPI_access_sn2);
153                 }
154         }
155 }
156
157 /*
158  * The following set of functions are used for the sending and receiving of
159  * IRQs (also known as IPIs). There are two flavors of IRQs, one that is
160  * associated with partition activity (SGI_XPC_ACTIVATE) and the other that
161  * is associated with channel activity (SGI_XPC_NOTIFY).
162  */
163
164 static u64
165 xpc_receive_IRQ_amo_sn2(struct amo *amo)
166 {
167         return FETCHOP_LOAD_OP(TO_AMO((u64)&amo->variable), FETCHOP_CLEAR);
168 }
169
170 static enum xp_retval
171 xpc_send_IRQ_sn2(struct amo *amo, u64 flag, int nasid, int phys_cpuid,
172                  int vector)
173 {
174         int ret = 0;
175         unsigned long irq_flags;
176
177         local_irq_save(irq_flags);
178
179         FETCHOP_STORE_OP(TO_AMO((u64)&amo->variable), FETCHOP_OR, flag);
180         sn_send_IPI_phys(nasid, phys_cpuid, vector, 0);
181
182         /*
183          * We must always use the nofault function regardless of whether we
184          * are on a Shub 1.1 system or a Shub 1.2 slice 0xc processor. If we
185          * didn't, we'd never know that the other partition is down and would
186          * keep sending IRQs and amos to it until the heartbeat times out.
187          */
188         ret = xp_nofault_PIOR((u64 *)GLOBAL_MMR_ADDR(NASID_GET(&amo->variable),
189                                                      xp_nofault_PIOR_target));
190
191         local_irq_restore(irq_flags);
192
193         return (ret == 0) ? xpSuccess : xpPioReadError;
194 }
195
196 static struct amo *
197 xpc_init_IRQ_amo_sn2(int index)
198 {
199         struct amo *amo = xpc_vars_sn2->amos_page + index;
200
201         (void)xpc_receive_IRQ_amo_sn2(amo);     /* clear amo variable */
202         return amo;
203 }
204
205 /*
206  * Functions associated with SGI_XPC_ACTIVATE IRQ.
207  */
208
209 /*
210  * Notify the heartbeat check thread that an activate IRQ has been received.
211  */
212 static irqreturn_t
213 xpc_handle_activate_IRQ_sn2(int irq, void *dev_id)
214 {
215         unsigned long irq_flags;
216
217         spin_lock_irqsave(&xpc_activate_IRQ_rcvd_lock, irq_flags);
218         xpc_activate_IRQ_rcvd++;
219         spin_unlock_irqrestore(&xpc_activate_IRQ_rcvd_lock, irq_flags);
220
221         wake_up_interruptible(&xpc_activate_IRQ_wq);
222         return IRQ_HANDLED;
223 }
224
225 /*
226  * Flag the appropriate amo variable and send an IRQ to the specified node.
227  */
228 static void
229 xpc_send_activate_IRQ_sn2(unsigned long amos_page_pa, int from_nasid,
230                           int to_nasid, int to_phys_cpuid)
231 {
232         struct amo *amos = (struct amo *)__va(amos_page_pa +
233                                               (XPC_ACTIVATE_IRQ_AMOS_SN2 *
234                                               sizeof(struct amo)));
235
236         (void)xpc_send_IRQ_sn2(&amos[BIT_WORD(from_nasid / 2)],
237                                BIT_MASK(from_nasid / 2), to_nasid,
238                                to_phys_cpuid, SGI_XPC_ACTIVATE);
239 }
240
241 static void
242 xpc_send_local_activate_IRQ_sn2(int from_nasid)
243 {
244         unsigned long irq_flags;
245         struct amo *amos = (struct amo *)__va(xpc_vars_sn2->amos_page_pa +
246                                               (XPC_ACTIVATE_IRQ_AMOS_SN2 *
247                                               sizeof(struct amo)));
248
249         /* fake the sending and receipt of an activate IRQ from remote nasid */
250         FETCHOP_STORE_OP(TO_AMO((u64)&amos[BIT_WORD(from_nasid / 2)].variable),
251                          FETCHOP_OR, BIT_MASK(from_nasid / 2));
252
253         spin_lock_irqsave(&xpc_activate_IRQ_rcvd_lock, irq_flags);
254         xpc_activate_IRQ_rcvd++;
255         spin_unlock_irqrestore(&xpc_activate_IRQ_rcvd_lock, irq_flags);
256
257         wake_up_interruptible(&xpc_activate_IRQ_wq);
258 }
259
260 /*
261  * Functions associated with SGI_XPC_NOTIFY IRQ.
262  */
263
264 /*
265  * Check to see if any chctl flags were sent from the specified partition.
266  */
267 static void
268 xpc_check_for_sent_chctl_flags_sn2(struct xpc_partition *part)
269 {
270         union xpc_channel_ctl_flags chctl;
271         unsigned long irq_flags;
272
273         chctl.all_flags = xpc_receive_IRQ_amo_sn2(part->sn.sn2.
274                                                   local_chctl_amo_va);
275         if (chctl.all_flags == 0)
276                 return;
277
278         spin_lock_irqsave(&part->chctl_lock, irq_flags);
279         part->chctl.all_flags |= chctl.all_flags;
280         spin_unlock_irqrestore(&part->chctl_lock, irq_flags);
281
282         dev_dbg(xpc_chan, "received notify IRQ from partid=%d, chctl.all_flags="
283                 "0x%llx\n", XPC_PARTID(part), chctl.all_flags);
284
285         xpc_wakeup_channel_mgr(part);
286 }
287
288 /*
289  * Handle the receipt of a SGI_XPC_NOTIFY IRQ by seeing whether the specified
290  * partition actually sent it. Since SGI_XPC_NOTIFY IRQs may be shared by more
291  * than one partition, we use an amo structure per partition to indicate
292  * whether a partition has sent an IRQ or not.  If it has, then wake up the
293  * associated kthread to handle it.
294  *
295  * All SGI_XPC_NOTIFY IRQs received by XPC are the result of IRQs sent by XPC
296  * running on other partitions.
297  *
298  * Noteworthy Arguments:
299  *
300  *      irq - Interrupt ReQuest number. NOT USED.
301  *
302  *      dev_id - partid of IRQ's potential sender.
303  */
304 static irqreturn_t
305 xpc_handle_notify_IRQ_sn2(int irq, void *dev_id)
306 {
307         short partid = (short)(u64)dev_id;
308         struct xpc_partition *part = &xpc_partitions[partid];
309
310         DBUG_ON(partid < 0 || partid >= XP_MAX_NPARTITIONS_SN2);
311
312         if (xpc_part_ref(part)) {
313                 xpc_check_for_sent_chctl_flags_sn2(part);
314
315                 xpc_part_deref(part);
316         }
317         return IRQ_HANDLED;
318 }
319
320 /*
321  * Check to see if xpc_handle_notify_IRQ_sn2() dropped any IRQs on the floor
322  * because the write to their associated amo variable completed after the IRQ
323  * was received.
324  */
325 static void
326 xpc_check_for_dropped_notify_IRQ_sn2(struct xpc_partition *part)
327 {
328         struct xpc_partition_sn2 *part_sn2 = &part->sn.sn2;
329
330         if (xpc_part_ref(part)) {
331                 xpc_check_for_sent_chctl_flags_sn2(part);
332
333                 part_sn2->dropped_notify_IRQ_timer.expires = jiffies +
334                     XPC_DROPPED_NOTIFY_IRQ_WAIT_INTERVAL;
335                 add_timer(&part_sn2->dropped_notify_IRQ_timer);
336                 xpc_part_deref(part);
337         }
338 }
339
340 /*
341  * Send a notify IRQ to the remote partition that is associated with the
342  * specified channel.
343  */
344 static void
345 xpc_send_notify_IRQ_sn2(struct xpc_channel *ch, u8 chctl_flag,
346                         char *chctl_flag_string, unsigned long *irq_flags)
347 {
348         struct xpc_partition *part = &xpc_partitions[ch->partid];
349         struct xpc_partition_sn2 *part_sn2 = &part->sn.sn2;
350         union xpc_channel_ctl_flags chctl = { 0 };
351         enum xp_retval ret;
352
353         if (likely(part->act_state != XPC_P_AS_DEACTIVATING)) {
354                 chctl.flags[ch->number] = chctl_flag;
355                 ret = xpc_send_IRQ_sn2(part_sn2->remote_chctl_amo_va,
356                                        chctl.all_flags,
357                                        part_sn2->notify_IRQ_nasid,
358                                        part_sn2->notify_IRQ_phys_cpuid,
359                                        SGI_XPC_NOTIFY);
360                 dev_dbg(xpc_chan, "%s sent to partid=%d, channel=%d, ret=%d\n",
361                         chctl_flag_string, ch->partid, ch->number, ret);
362                 if (unlikely(ret != xpSuccess)) {
363                         if (irq_flags != NULL)
364                                 spin_unlock_irqrestore(&ch->lock, *irq_flags);
365                         XPC_DEACTIVATE_PARTITION(part, ret);
366                         if (irq_flags != NULL)
367                                 spin_lock_irqsave(&ch->lock, *irq_flags);
368                 }
369         }
370 }
371
372 #define XPC_SEND_NOTIFY_IRQ_SN2(_ch, _ipi_f, _irq_f) \
373                 xpc_send_notify_IRQ_sn2(_ch, _ipi_f, #_ipi_f, _irq_f)
374
375 /*
376  * Make it look like the remote partition, which is associated with the
377  * specified channel, sent us a notify IRQ. This faked IRQ will be handled
378  * by xpc_check_for_dropped_notify_IRQ_sn2().
379  */
380 static void
381 xpc_send_local_notify_IRQ_sn2(struct xpc_channel *ch, u8 chctl_flag,
382                               char *chctl_flag_string)
383 {
384         struct xpc_partition *part = &xpc_partitions[ch->partid];
385         union xpc_channel_ctl_flags chctl = { 0 };
386
387         chctl.flags[ch->number] = chctl_flag;
388         FETCHOP_STORE_OP(TO_AMO((u64)&part->sn.sn2.local_chctl_amo_va->
389                                 variable), FETCHOP_OR, chctl.all_flags);
390         dev_dbg(xpc_chan, "%s sent local from partid=%d, channel=%d\n",
391                 chctl_flag_string, ch->partid, ch->number);
392 }
393
394 #define XPC_SEND_LOCAL_NOTIFY_IRQ_SN2(_ch, _ipi_f) \
395                 xpc_send_local_notify_IRQ_sn2(_ch, _ipi_f, #_ipi_f)
396
397 static void
398 xpc_send_chctl_closerequest_sn2(struct xpc_channel *ch,
399                                 unsigned long *irq_flags)
400 {
401         struct xpc_openclose_args *args = ch->sn.sn2.local_openclose_args;
402
403         args->reason = ch->reason;
404         XPC_SEND_NOTIFY_IRQ_SN2(ch, XPC_CHCTL_CLOSEREQUEST, irq_flags);
405 }
406
407 static void
408 xpc_send_chctl_closereply_sn2(struct xpc_channel *ch, unsigned long *irq_flags)
409 {
410         XPC_SEND_NOTIFY_IRQ_SN2(ch, XPC_CHCTL_CLOSEREPLY, irq_flags);
411 }
412
413 static void
414 xpc_send_chctl_openrequest_sn2(struct xpc_channel *ch, unsigned long *irq_flags)
415 {
416         struct xpc_openclose_args *args = ch->sn.sn2.local_openclose_args;
417
418         args->entry_size = ch->entry_size;
419         args->local_nentries = ch->local_nentries;
420         XPC_SEND_NOTIFY_IRQ_SN2(ch, XPC_CHCTL_OPENREQUEST, irq_flags);
421 }
422
423 static void
424 xpc_send_chctl_openreply_sn2(struct xpc_channel *ch, unsigned long *irq_flags)
425 {
426         struct xpc_openclose_args *args = ch->sn.sn2.local_openclose_args;
427
428         args->remote_nentries = ch->remote_nentries;
429         args->local_nentries = ch->local_nentries;
430         args->local_msgqueue_pa = xp_pa(ch->sn.sn2.local_msgqueue);
431         XPC_SEND_NOTIFY_IRQ_SN2(ch, XPC_CHCTL_OPENREPLY, irq_flags);
432 }
433
434 static void
435 xpc_send_chctl_opencomplete_sn2(struct xpc_channel *ch,
436                                 unsigned long *irq_flags)
437 {
438         XPC_SEND_NOTIFY_IRQ_SN2(ch, XPC_CHCTL_OPENCOMPLETE, irq_flags);
439 }
440
441 static void
442 xpc_send_chctl_msgrequest_sn2(struct xpc_channel *ch)
443 {
444         XPC_SEND_NOTIFY_IRQ_SN2(ch, XPC_CHCTL_MSGREQUEST, NULL);
445 }
446
447 static void
448 xpc_send_chctl_local_msgrequest_sn2(struct xpc_channel *ch)
449 {
450         XPC_SEND_LOCAL_NOTIFY_IRQ_SN2(ch, XPC_CHCTL_MSGREQUEST);
451 }
452
453 static enum xp_retval
454 xpc_save_remote_msgqueue_pa_sn2(struct xpc_channel *ch,
455                                 unsigned long msgqueue_pa)
456 {
457         ch->sn.sn2.remote_msgqueue_pa = msgqueue_pa;
458         return xpSuccess;
459 }
460
461 /*
462  * This next set of functions are used to keep track of when a partition is
463  * potentially engaged in accessing memory belonging to another partition.
464  */
465
466 static void
467 xpc_indicate_partition_engaged_sn2(struct xpc_partition *part)
468 {
469         unsigned long irq_flags;
470         struct amo *amo = (struct amo *)__va(part->sn.sn2.remote_amos_page_pa +
471                                              (XPC_ENGAGED_PARTITIONS_AMO_SN2 *
472                                              sizeof(struct amo)));
473
474         local_irq_save(irq_flags);
475
476         /* set bit corresponding to our partid in remote partition's amo */
477         FETCHOP_STORE_OP(TO_AMO((u64)&amo->variable), FETCHOP_OR,
478                          BIT(sn_partition_id));
479
480         /*
481          * We must always use the nofault function regardless of whether we
482          * are on a Shub 1.1 system or a Shub 1.2 slice 0xc processor. If we
483          * didn't, we'd never know that the other partition is down and would
484          * keep sending IRQs and amos to it until the heartbeat times out.
485          */
486         (void)xp_nofault_PIOR((u64 *)GLOBAL_MMR_ADDR(NASID_GET(&amo->
487                                                                variable),
488                                                      xp_nofault_PIOR_target));
489
490         local_irq_restore(irq_flags);
491 }
492
493 static void
494 xpc_indicate_partition_disengaged_sn2(struct xpc_partition *part)
495 {
496         struct xpc_partition_sn2 *part_sn2 = &part->sn.sn2;
497         unsigned long irq_flags;
498         struct amo *amo = (struct amo *)__va(part_sn2->remote_amos_page_pa +
499                                              (XPC_ENGAGED_PARTITIONS_AMO_SN2 *
500                                              sizeof(struct amo)));
501
502         local_irq_save(irq_flags);
503
504         /* clear bit corresponding to our partid in remote partition's amo */
505         FETCHOP_STORE_OP(TO_AMO((u64)&amo->variable), FETCHOP_AND,
506                          ~BIT(sn_partition_id));
507
508         /*
509          * We must always use the nofault function regardless of whether we
510          * are on a Shub 1.1 system or a Shub 1.2 slice 0xc processor. If we
511          * didn't, we'd never know that the other partition is down and would
512          * keep sending IRQs and amos to it until the heartbeat times out.
513          */
514         (void)xp_nofault_PIOR((u64 *)GLOBAL_MMR_ADDR(NASID_GET(&amo->
515                                                                variable),
516                                                      xp_nofault_PIOR_target));
517
518         local_irq_restore(irq_flags);
519
520         /*
521          * Send activate IRQ to get other side to see that we've cleared our
522          * bit in their engaged partitions amo.
523          */
524         xpc_send_activate_IRQ_sn2(part_sn2->remote_amos_page_pa,
525                                   cnodeid_to_nasid(0),
526                                   part_sn2->activate_IRQ_nasid,
527                                   part_sn2->activate_IRQ_phys_cpuid);
528 }
529
530 static void
531 xpc_assume_partition_disengaged_sn2(short partid)
532 {
533         struct amo *amo = xpc_vars_sn2->amos_page +
534                           XPC_ENGAGED_PARTITIONS_AMO_SN2;
535
536         /* clear bit(s) based on partid mask in our partition's amo */
537         FETCHOP_STORE_OP(TO_AMO((u64)&amo->variable), FETCHOP_AND,
538                          ~BIT(partid));
539 }
540
541 static int
542 xpc_partition_engaged_sn2(short partid)
543 {
544         struct amo *amo = xpc_vars_sn2->amos_page +
545                           XPC_ENGAGED_PARTITIONS_AMO_SN2;
546
547         /* our partition's amo variable ANDed with partid mask */
548         return (FETCHOP_LOAD_OP(TO_AMO((u64)&amo->variable), FETCHOP_LOAD) &
549                 BIT(partid)) != 0;
550 }
551
552 static int
553 xpc_any_partition_engaged_sn2(void)
554 {
555         struct amo *amo = xpc_vars_sn2->amos_page +
556                           XPC_ENGAGED_PARTITIONS_AMO_SN2;
557
558         /* our partition's amo variable */
559         return FETCHOP_LOAD_OP(TO_AMO((u64)&amo->variable), FETCHOP_LOAD) != 0;
560 }
561
562 /* original protection values for each node */
563 static u64 xpc_prot_vec_sn2[MAX_NUMNODES];
564
565 /*
566  * Change protections to allow amo operations on non-Shub 1.1 systems.
567  */
568 static enum xp_retval
569 xpc_allow_amo_ops_sn2(struct amo *amos_page)
570 {
571         enum xp_retval ret = xpSuccess;
572
573         /*
574          * On SHUB 1.1, we cannot call sn_change_memprotect() since the BIST
575          * collides with memory operations. On those systems we call
576          * xpc_allow_amo_ops_shub_wars_1_1_sn2() instead.
577          */
578         if (!enable_shub_wars_1_1())
579                 ret = xp_expand_memprotect(ia64_tpa((u64)amos_page), PAGE_SIZE);
580
581         return ret;
582 }
583
584 /*
585  * Change protections to allow amo operations on Shub 1.1 systems.
586  */
587 static void
588 xpc_allow_amo_ops_shub_wars_1_1_sn2(void)
589 {
590         int node;
591         int nasid;
592
593         if (!enable_shub_wars_1_1())
594                 return;
595
596         for_each_online_node(node) {
597                 nasid = cnodeid_to_nasid(node);
598                 /* save current protection values */
599                 xpc_prot_vec_sn2[node] =
600                     (u64)HUB_L((u64 *)GLOBAL_MMR_ADDR(nasid,
601                                                   SH1_MD_DQLP_MMR_DIR_PRIVEC0));
602                 /* open up everything */
603                 HUB_S((u64 *)GLOBAL_MMR_ADDR(nasid,
604                                              SH1_MD_DQLP_MMR_DIR_PRIVEC0),
605                       -1UL);
606                 HUB_S((u64 *)GLOBAL_MMR_ADDR(nasid,
607                                              SH1_MD_DQRP_MMR_DIR_PRIVEC0),
608                       -1UL);
609         }
610 }
611
612 static enum xp_retval
613 xpc_get_partition_rsvd_page_pa_sn2(void *buf, u64 *cookie, unsigned long *rp_pa,
614                                    size_t *len)
615 {
616         s64 status;
617         enum xp_retval ret;
618
619         status = sn_partition_reserved_page_pa((u64)buf, cookie,
620                         (u64 *)rp_pa, (u64 *)len);
621         if (status == SALRET_OK)
622                 ret = xpSuccess;
623         else if (status == SALRET_MORE_PASSES)
624                 ret = xpNeedMoreInfo;
625         else
626                 ret = xpSalError;
627
628         return ret;
629 }
630
631
632 static int
633 xpc_setup_rsvd_page_sn2(struct xpc_rsvd_page *rp)
634 {
635         struct amo *amos_page;
636         int i;
637         int ret;
638
639         xpc_vars_sn2 = XPC_RP_VARS(rp);
640
641         rp->sn.sn2.vars_pa = xp_pa(xpc_vars_sn2);
642
643         /* vars_part array follows immediately after vars */
644         xpc_vars_part_sn2 = (struct xpc_vars_part_sn2 *)((u8 *)XPC_RP_VARS(rp) +
645                                                          XPC_RP_VARS_SIZE);
646
647         /*
648          * Before clearing xpc_vars_sn2, see if a page of amos had been
649          * previously allocated. If not we'll need to allocate one and set
650          * permissions so that cross-partition amos are allowed.
651          *
652          * The allocated amo page needs MCA reporting to remain disabled after
653          * XPC has unloaded.  To make this work, we keep a copy of the pointer
654          * to this page (i.e., amos_page) in the struct xpc_vars_sn2 structure,
655          * which is pointed to by the reserved page, and re-use that saved copy
656          * on subsequent loads of XPC. This amo page is never freed, and its
657          * memory protections are never restricted.
658          */
659         amos_page = xpc_vars_sn2->amos_page;
660         if (amos_page == NULL) {
661                 amos_page = (struct amo *)TO_AMO(uncached_alloc_page(0, 1));
662                 if (amos_page == NULL) {
663                         dev_err(xpc_part, "can't allocate page of amos\n");
664                         return -ENOMEM;
665                 }
666
667                 /*
668                  * Open up amo-R/W to cpu.  This is done on Shub 1.1 systems
669                  * when xpc_allow_amo_ops_shub_wars_1_1_sn2() is called.
670                  */
671                 ret = xpc_allow_amo_ops_sn2(amos_page);
672                 if (ret != xpSuccess) {
673                         dev_err(xpc_part, "can't allow amo operations\n");
674                         uncached_free_page(__IA64_UNCACHED_OFFSET |
675                                            TO_PHYS((u64)amos_page), 1);
676                         return -EPERM;
677                 }
678         }
679
680         /* clear xpc_vars_sn2 */
681         memset(xpc_vars_sn2, 0, sizeof(struct xpc_vars_sn2));
682
683         xpc_vars_sn2->version = XPC_V_VERSION;
684         xpc_vars_sn2->activate_IRQ_nasid = cpuid_to_nasid(0);
685         xpc_vars_sn2->activate_IRQ_phys_cpuid = cpu_physical_id(0);
686         xpc_vars_sn2->vars_part_pa = xp_pa(xpc_vars_part_sn2);
687         xpc_vars_sn2->amos_page_pa = ia64_tpa((u64)amos_page);
688         xpc_vars_sn2->amos_page = amos_page;    /* save for next load of XPC */
689
690         /* clear xpc_vars_part_sn2 */
691         memset((u64 *)xpc_vars_part_sn2, 0, sizeof(struct xpc_vars_part_sn2) *
692                XP_MAX_NPARTITIONS_SN2);
693
694         /* initialize the activate IRQ related amo variables */
695         for (i = 0; i < xpc_nasid_mask_nlongs; i++)
696                 (void)xpc_init_IRQ_amo_sn2(XPC_ACTIVATE_IRQ_AMOS_SN2 + i);
697
698         /* initialize the engaged remote partitions related amo variables */
699         (void)xpc_init_IRQ_amo_sn2(XPC_ENGAGED_PARTITIONS_AMO_SN2);
700         (void)xpc_init_IRQ_amo_sn2(XPC_DEACTIVATE_REQUEST_AMO_SN2);
701
702         return 0;
703 }
704
705 static int
706 xpc_hb_allowed_sn2(short partid, void *heartbeating_to_mask)
707 {
708         return test_bit(partid, heartbeating_to_mask);
709 }
710
711 static void
712 xpc_allow_hb_sn2(short partid)
713 {
714         DBUG_ON(xpc_vars_sn2 == NULL);
715         set_bit(partid, xpc_vars_sn2->heartbeating_to_mask);
716 }
717
718 static void
719 xpc_disallow_hb_sn2(short partid)
720 {
721         DBUG_ON(xpc_vars_sn2 == NULL);
722         clear_bit(partid, xpc_vars_sn2->heartbeating_to_mask);
723 }
724
725 static void
726 xpc_disallow_all_hbs_sn2(void)
727 {
728         DBUG_ON(xpc_vars_sn2 == NULL);
729         bitmap_zero(xpc_vars_sn2->heartbeating_to_mask, xp_max_npartitions);
730 }
731
732 static void
733 xpc_increment_heartbeat_sn2(void)
734 {
735         xpc_vars_sn2->heartbeat++;
736 }
737
738 static void
739 xpc_offline_heartbeat_sn2(void)
740 {
741         xpc_increment_heartbeat_sn2();
742         xpc_vars_sn2->heartbeat_offline = 1;
743 }
744
745 static void
746 xpc_online_heartbeat_sn2(void)
747 {
748         xpc_increment_heartbeat_sn2();
749         xpc_vars_sn2->heartbeat_offline = 0;
750 }
751
752 static void
753 xpc_heartbeat_init_sn2(void)
754 {
755         DBUG_ON(xpc_vars_sn2 == NULL);
756
757         bitmap_zero(xpc_vars_sn2->heartbeating_to_mask, XP_MAX_NPARTITIONS_SN2);
758         xpc_online_heartbeat_sn2();
759 }
760
761 static void
762 xpc_heartbeat_exit_sn2(void)
763 {
764         xpc_offline_heartbeat_sn2();
765 }
766
767 static enum xp_retval
768 xpc_get_remote_heartbeat_sn2(struct xpc_partition *part)
769 {
770         struct xpc_vars_sn2 *remote_vars;
771         enum xp_retval ret;
772
773         remote_vars = (struct xpc_vars_sn2 *)xpc_remote_copy_buffer_sn2;
774
775         /* pull the remote vars structure that contains the heartbeat */
776         ret = xp_remote_memcpy(xp_pa(remote_vars),
777                                part->sn.sn2.remote_vars_pa,
778                                XPC_RP_VARS_SIZE);
779         if (ret != xpSuccess)
780                 return ret;
781
782         dev_dbg(xpc_part, "partid=%d, heartbeat=%lld, last_heartbeat=%lld, "
783                 "heartbeat_offline=%lld, HB_mask[0]=0x%lx\n", XPC_PARTID(part),
784                 remote_vars->heartbeat, part->last_heartbeat,
785                 remote_vars->heartbeat_offline,
786                 remote_vars->heartbeating_to_mask[0]);
787
788         if ((remote_vars->heartbeat == part->last_heartbeat &&
789             !remote_vars->heartbeat_offline) ||
790             !xpc_hb_allowed_sn2(sn_partition_id,
791                                 remote_vars->heartbeating_to_mask)) {
792                 ret = xpNoHeartbeat;
793         } else {
794                 part->last_heartbeat = remote_vars->heartbeat;
795         }
796
797         return ret;
798 }
799
800 /*
801  * Get a copy of the remote partition's XPC variables from the reserved page.
802  *
803  * remote_vars points to a buffer that is cacheline aligned for BTE copies and
804  * assumed to be of size XPC_RP_VARS_SIZE.
805  */
806 static enum xp_retval
807 xpc_get_remote_vars_sn2(unsigned long remote_vars_pa,
808                         struct xpc_vars_sn2 *remote_vars)
809 {
810         enum xp_retval ret;
811
812         if (remote_vars_pa == 0)
813                 return xpVarsNotSet;
814
815         /* pull over the cross partition variables */
816         ret = xp_remote_memcpy(xp_pa(remote_vars), remote_vars_pa,
817                                XPC_RP_VARS_SIZE);
818         if (ret != xpSuccess)
819                 return ret;
820
821         if (XPC_VERSION_MAJOR(remote_vars->version) !=
822             XPC_VERSION_MAJOR(XPC_V_VERSION)) {
823                 return xpBadVersion;
824         }
825
826         return xpSuccess;
827 }
828
829 static void
830 xpc_request_partition_activation_sn2(struct xpc_rsvd_page *remote_rp,
831                                      unsigned long remote_rp_pa, int nasid)
832 {
833         xpc_send_local_activate_IRQ_sn2(nasid);
834 }
835
836 static void
837 xpc_request_partition_reactivation_sn2(struct xpc_partition *part)
838 {
839         xpc_send_local_activate_IRQ_sn2(part->sn.sn2.activate_IRQ_nasid);
840 }
841
842 static void
843 xpc_request_partition_deactivation_sn2(struct xpc_partition *part)
844 {
845         struct xpc_partition_sn2 *part_sn2 = &part->sn.sn2;
846         unsigned long irq_flags;
847         struct amo *amo = (struct amo *)__va(part_sn2->remote_amos_page_pa +
848                                              (XPC_DEACTIVATE_REQUEST_AMO_SN2 *
849                                              sizeof(struct amo)));
850
851         local_irq_save(irq_flags);
852
853         /* set bit corresponding to our partid in remote partition's amo */
854         FETCHOP_STORE_OP(TO_AMO((u64)&amo->variable), FETCHOP_OR,
855                          BIT(sn_partition_id));
856
857         /*
858          * We must always use the nofault function regardless of whether we
859          * are on a Shub 1.1 system or a Shub 1.2 slice 0xc processor. If we
860          * didn't, we'd never know that the other partition is down and would
861          * keep sending IRQs and amos to it until the heartbeat times out.
862          */
863         (void)xp_nofault_PIOR((u64 *)GLOBAL_MMR_ADDR(NASID_GET(&amo->
864                                                                variable),
865                                                      xp_nofault_PIOR_target));
866
867         local_irq_restore(irq_flags);
868
869         /*
870          * Send activate IRQ to get other side to see that we've set our
871          * bit in their deactivate request amo.
872          */
873         xpc_send_activate_IRQ_sn2(part_sn2->remote_amos_page_pa,
874                                   cnodeid_to_nasid(0),
875                                   part_sn2->activate_IRQ_nasid,
876                                   part_sn2->activate_IRQ_phys_cpuid);
877 }
878
879 static void
880 xpc_cancel_partition_deactivation_request_sn2(struct xpc_partition *part)
881 {
882         unsigned long irq_flags;
883         struct amo *amo = (struct amo *)__va(part->sn.sn2.remote_amos_page_pa +
884                                              (XPC_DEACTIVATE_REQUEST_AMO_SN2 *
885                                              sizeof(struct amo)));
886
887         local_irq_save(irq_flags);
888
889         /* clear bit corresponding to our partid in remote partition's amo */
890         FETCHOP_STORE_OP(TO_AMO((u64)&amo->variable), FETCHOP_AND,
891                          ~BIT(sn_partition_id));
892
893         /*
894          * We must always use the nofault function regardless of whether we
895          * are on a Shub 1.1 system or a Shub 1.2 slice 0xc processor. If we
896          * didn't, we'd never know that the other partition is down and would
897          * keep sending IRQs and amos to it until the heartbeat times out.
898          */
899         (void)xp_nofault_PIOR((u64 *)GLOBAL_MMR_ADDR(NASID_GET(&amo->
900                                                                variable),
901                                                      xp_nofault_PIOR_target));
902
903         local_irq_restore(irq_flags);
904 }
905
906 static int
907 xpc_partition_deactivation_requested_sn2(short partid)
908 {
909         struct amo *amo = xpc_vars_sn2->amos_page +
910                           XPC_DEACTIVATE_REQUEST_AMO_SN2;
911
912         /* our partition's amo variable ANDed with partid mask */
913         return (FETCHOP_LOAD_OP(TO_AMO((u64)&amo->variable), FETCHOP_LOAD) &
914                 BIT(partid)) != 0;
915 }
916
917 /*
918  * Update the remote partition's info.
919  */
920 static void
921 xpc_update_partition_info_sn2(struct xpc_partition *part, u8 remote_rp_version,
922                               unsigned long *remote_rp_ts_jiffies,
923                               unsigned long remote_rp_pa,
924                               unsigned long remote_vars_pa,
925                               struct xpc_vars_sn2 *remote_vars)
926 {
927         struct xpc_partition_sn2 *part_sn2 = &part->sn.sn2;
928
929         part->remote_rp_version = remote_rp_version;
930         dev_dbg(xpc_part, "  remote_rp_version = 0x%016x\n",
931                 part->remote_rp_version);
932
933         part->remote_rp_ts_jiffies = *remote_rp_ts_jiffies;
934         dev_dbg(xpc_part, "  remote_rp_ts_jiffies = 0x%016lx\n",
935                 part->remote_rp_ts_jiffies);
936
937         part->remote_rp_pa = remote_rp_pa;
938         dev_dbg(xpc_part, "  remote_rp_pa = 0x%016lx\n", part->remote_rp_pa);
939
940         part_sn2->remote_vars_pa = remote_vars_pa;
941         dev_dbg(xpc_part, "  remote_vars_pa = 0x%016lx\n",
942                 part_sn2->remote_vars_pa);
943
944         part->last_heartbeat = remote_vars->heartbeat - 1;
945         dev_dbg(xpc_part, "  last_heartbeat = 0x%016llx\n",
946                 part->last_heartbeat);
947
948         part_sn2->remote_vars_part_pa = remote_vars->vars_part_pa;
949         dev_dbg(xpc_part, "  remote_vars_part_pa = 0x%016lx\n",
950                 part_sn2->remote_vars_part_pa);
951
952         part_sn2->activate_IRQ_nasid = remote_vars->activate_IRQ_nasid;
953         dev_dbg(xpc_part, "  activate_IRQ_nasid = 0x%x\n",
954                 part_sn2->activate_IRQ_nasid);
955
956         part_sn2->activate_IRQ_phys_cpuid =
957             remote_vars->activate_IRQ_phys_cpuid;
958         dev_dbg(xpc_part, "  activate_IRQ_phys_cpuid = 0x%x\n",
959                 part_sn2->activate_IRQ_phys_cpuid);
960
961         part_sn2->remote_amos_page_pa = remote_vars->amos_page_pa;
962         dev_dbg(xpc_part, "  remote_amos_page_pa = 0x%lx\n",
963                 part_sn2->remote_amos_page_pa);
964
965         part_sn2->remote_vars_version = remote_vars->version;
966         dev_dbg(xpc_part, "  remote_vars_version = 0x%x\n",
967                 part_sn2->remote_vars_version);
968 }
969
970 /*
971  * Prior code has determined the nasid which generated a activate IRQ.
972  * Inspect that nasid to determine if its partition needs to be activated
973  * or deactivated.
974  *
975  * A partition is considered "awaiting activation" if our partition
976  * flags indicate it is not active and it has a heartbeat.  A
977  * partition is considered "awaiting deactivation" if our partition
978  * flags indicate it is active but it has no heartbeat or it is not
979  * sending its heartbeat to us.
980  *
981  * To determine the heartbeat, the remote nasid must have a properly
982  * initialized reserved page.
983  */
984 static void
985 xpc_identify_activate_IRQ_req_sn2(int nasid)
986 {
987         struct xpc_rsvd_page *remote_rp;
988         struct xpc_vars_sn2 *remote_vars;
989         unsigned long remote_rp_pa;
990         unsigned long remote_vars_pa;
991         int remote_rp_version;
992         int reactivate = 0;
993         unsigned long remote_rp_ts_jiffies = 0;
994         short partid;
995         struct xpc_partition *part;
996         struct xpc_partition_sn2 *part_sn2;
997         enum xp_retval ret;
998
999         /* pull over the reserved page structure */
1000
1001         remote_rp = (struct xpc_rsvd_page *)xpc_remote_copy_buffer_sn2;
1002
1003         ret = xpc_get_remote_rp(nasid, NULL, remote_rp, &remote_rp_pa);
1004         if (ret != xpSuccess) {
1005                 dev_warn(xpc_part, "unable to get reserved page from nasid %d, "
1006                          "which sent interrupt, reason=%d\n", nasid, ret);
1007                 return;
1008         }
1009
1010         remote_vars_pa = remote_rp->sn.sn2.vars_pa;
1011         remote_rp_version = remote_rp->version;
1012         remote_rp_ts_jiffies = remote_rp->ts_jiffies;
1013
1014         partid = remote_rp->SAL_partid;
1015         part = &xpc_partitions[partid];
1016         part_sn2 = &part->sn.sn2;
1017
1018         /* pull over the cross partition variables */
1019
1020         remote_vars = (struct xpc_vars_sn2 *)xpc_remote_copy_buffer_sn2;
1021
1022         ret = xpc_get_remote_vars_sn2(remote_vars_pa, remote_vars);
1023         if (ret != xpSuccess) {
1024                 dev_warn(xpc_part, "unable to get XPC variables from nasid %d, "
1025                          "which sent interrupt, reason=%d\n", nasid, ret);
1026
1027                 XPC_DEACTIVATE_PARTITION(part, ret);
1028                 return;
1029         }
1030
1031         part->activate_IRQ_rcvd++;
1032
1033         dev_dbg(xpc_part, "partid for nasid %d is %d; IRQs = %d; HB = "
1034                 "%lld:0x%lx\n", (int)nasid, (int)partid,
1035                 part->activate_IRQ_rcvd,
1036                 remote_vars->heartbeat, remote_vars->heartbeating_to_mask[0]);
1037
1038         if (xpc_partition_disengaged(part) &&
1039             part->act_state == XPC_P_AS_INACTIVE) {
1040
1041                 xpc_update_partition_info_sn2(part, remote_rp_version,
1042                                               &remote_rp_ts_jiffies,
1043                                               remote_rp_pa, remote_vars_pa,
1044                                               remote_vars);
1045
1046                 if (xpc_partition_deactivation_requested_sn2(partid)) {
1047                         /*
1048                          * Other side is waiting on us to deactivate even though
1049                          * we already have.
1050                          */
1051                         return;
1052                 }
1053
1054                 xpc_activate_partition(part);
1055                 return;
1056         }
1057
1058         DBUG_ON(part->remote_rp_version == 0);
1059         DBUG_ON(part_sn2->remote_vars_version == 0);
1060
1061         if (remote_rp_ts_jiffies != part->remote_rp_ts_jiffies) {
1062
1063                 /* the other side rebooted */
1064
1065                 DBUG_ON(xpc_partition_engaged_sn2(partid));
1066                 DBUG_ON(xpc_partition_deactivation_requested_sn2(partid));
1067
1068                 xpc_update_partition_info_sn2(part, remote_rp_version,
1069                                               &remote_rp_ts_jiffies,
1070                                               remote_rp_pa, remote_vars_pa,
1071                                               remote_vars);
1072                 reactivate = 1;
1073         }
1074
1075         if (part->disengage_timeout > 0 && !xpc_partition_disengaged(part)) {
1076                 /* still waiting on other side to disengage from us */
1077                 return;
1078         }
1079
1080         if (reactivate)
1081                 XPC_DEACTIVATE_PARTITION(part, xpReactivating);
1082         else if (xpc_partition_deactivation_requested_sn2(partid))
1083                 XPC_DEACTIVATE_PARTITION(part, xpOtherGoingDown);
1084 }
1085
1086 /*
1087  * Loop through the activation amo variables and process any bits
1088  * which are set.  Each bit indicates a nasid sending a partition
1089  * activation or deactivation request.
1090  *
1091  * Return #of IRQs detected.
1092  */
1093 int
1094 xpc_identify_activate_IRQ_sender_sn2(void)
1095 {
1096         int l;
1097         int b;
1098         unsigned long nasid_mask_long;
1099         u64 nasid;              /* remote nasid */
1100         int n_IRQs_detected = 0;
1101         struct amo *act_amos;
1102
1103         act_amos = xpc_vars_sn2->amos_page + XPC_ACTIVATE_IRQ_AMOS_SN2;
1104
1105         /* scan through activate amo variables looking for non-zero entries */
1106         for (l = 0; l < xpc_nasid_mask_nlongs; l++) {
1107
1108                 if (xpc_exiting)
1109                         break;
1110
1111                 nasid_mask_long = xpc_receive_IRQ_amo_sn2(&act_amos[l]);
1112
1113                 b = find_first_bit(&nasid_mask_long, BITS_PER_LONG);
1114                 if (b >= BITS_PER_LONG) {
1115                         /* no IRQs from nasids in this amo variable */
1116                         continue;
1117                 }
1118
1119                 dev_dbg(xpc_part, "amo[%d] gave back 0x%lx\n", l,
1120                         nasid_mask_long);
1121
1122                 /*
1123                  * If this nasid has been added to the machine since
1124                  * our partition was reset, this will retain the
1125                  * remote nasid in our reserved pages machine mask.
1126                  * This is used in the event of module reload.
1127                  */
1128                 xpc_mach_nasids[l] |= nasid_mask_long;
1129
1130                 /* locate the nasid(s) which sent interrupts */
1131
1132                 do {
1133                         n_IRQs_detected++;
1134                         nasid = (l * BITS_PER_LONG + b) * 2;
1135                         dev_dbg(xpc_part, "interrupt from nasid %lld\n", nasid);
1136                         xpc_identify_activate_IRQ_req_sn2(nasid);
1137
1138                         b = find_next_bit(&nasid_mask_long, BITS_PER_LONG,
1139                                           b + 1);
1140                 } while (b < BITS_PER_LONG);
1141         }
1142         return n_IRQs_detected;
1143 }
1144
1145 static void
1146 xpc_process_activate_IRQ_rcvd_sn2(void)
1147 {
1148         unsigned long irq_flags;
1149         int n_IRQs_expected;
1150         int n_IRQs_detected;
1151
1152         spin_lock_irqsave(&xpc_activate_IRQ_rcvd_lock, irq_flags);
1153         n_IRQs_expected = xpc_activate_IRQ_rcvd;
1154         xpc_activate_IRQ_rcvd = 0;
1155         spin_unlock_irqrestore(&xpc_activate_IRQ_rcvd_lock, irq_flags);
1156
1157         n_IRQs_detected = xpc_identify_activate_IRQ_sender_sn2();
1158         if (n_IRQs_detected < n_IRQs_expected) {
1159                 /* retry once to help avoid missing amo */
1160                 (void)xpc_identify_activate_IRQ_sender_sn2();
1161         }
1162 }
1163
1164 /*
1165  * Setup the channel structures that are sn2 specific.
1166  */
1167 static enum xp_retval
1168 xpc_setup_ch_structures_sn2(struct xpc_partition *part)
1169 {
1170         struct xpc_partition_sn2 *part_sn2 = &part->sn.sn2;
1171         struct xpc_channel_sn2 *ch_sn2;
1172         enum xp_retval retval;
1173         int ret;
1174         int cpuid;
1175         int ch_number;
1176         struct timer_list *timer;
1177         short partid = XPC_PARTID(part);
1178
1179         /* allocate all the required GET/PUT values */
1180
1181         part_sn2->local_GPs =
1182             xpc_kzalloc_cacheline_aligned(XPC_GP_SIZE, GFP_KERNEL,
1183                                           &part_sn2->local_GPs_base);
1184         if (part_sn2->local_GPs == NULL) {
1185                 dev_err(xpc_chan, "can't get memory for local get/put "
1186                         "values\n");
1187                 return xpNoMemory;
1188         }
1189
1190         part_sn2->remote_GPs =
1191             xpc_kzalloc_cacheline_aligned(XPC_GP_SIZE, GFP_KERNEL,
1192                                           &part_sn2->remote_GPs_base);
1193         if (part_sn2->remote_GPs == NULL) {
1194                 dev_err(xpc_chan, "can't get memory for remote get/put "
1195                         "values\n");
1196                 retval = xpNoMemory;
1197                 goto out_1;
1198         }
1199
1200         part_sn2->remote_GPs_pa = 0;
1201
1202         /* allocate all the required open and close args */
1203
1204         part_sn2->local_openclose_args =
1205             xpc_kzalloc_cacheline_aligned(XPC_OPENCLOSE_ARGS_SIZE,
1206                                           GFP_KERNEL, &part_sn2->
1207                                           local_openclose_args_base);
1208         if (part_sn2->local_openclose_args == NULL) {
1209                 dev_err(xpc_chan, "can't get memory for local connect args\n");
1210                 retval = xpNoMemory;
1211                 goto out_2;
1212         }
1213
1214         part_sn2->remote_openclose_args_pa = 0;
1215
1216         part_sn2->local_chctl_amo_va = xpc_init_IRQ_amo_sn2(partid);
1217
1218         part_sn2->notify_IRQ_nasid = 0;
1219         part_sn2->notify_IRQ_phys_cpuid = 0;
1220         part_sn2->remote_chctl_amo_va = NULL;
1221
1222         sprintf(part_sn2->notify_IRQ_owner, "xpc%02d", partid);
1223         ret = request_irq(SGI_XPC_NOTIFY, xpc_handle_notify_IRQ_sn2,
1224                           IRQF_SHARED, part_sn2->notify_IRQ_owner,
1225                           (void *)(u64)partid);
1226         if (ret != 0) {
1227                 dev_err(xpc_chan, "can't register NOTIFY IRQ handler, "
1228                         "errno=%d\n", -ret);
1229                 retval = xpLackOfResources;
1230                 goto out_3;
1231         }
1232
1233         /* Setup a timer to check for dropped notify IRQs */
1234         timer = &part_sn2->dropped_notify_IRQ_timer;
1235         init_timer(timer);
1236         timer->function =
1237             (void (*)(unsigned long))xpc_check_for_dropped_notify_IRQ_sn2;
1238         timer->data = (unsigned long)part;
1239         timer->expires = jiffies + XPC_DROPPED_NOTIFY_IRQ_WAIT_INTERVAL;
1240         add_timer(timer);
1241
1242         for (ch_number = 0; ch_number < part->nchannels; ch_number++) {
1243                 ch_sn2 = &part->channels[ch_number].sn.sn2;
1244
1245                 ch_sn2->local_GP = &part_sn2->local_GPs[ch_number];
1246                 ch_sn2->local_openclose_args =
1247                     &part_sn2->local_openclose_args[ch_number];
1248
1249                 mutex_init(&ch_sn2->msg_to_pull_mutex);
1250         }
1251
1252         /*
1253          * Setup the per partition specific variables required by the
1254          * remote partition to establish channel connections with us.
1255          *
1256          * The setting of the magic # indicates that these per partition
1257          * specific variables are ready to be used.
1258          */
1259         xpc_vars_part_sn2[partid].GPs_pa = xp_pa(part_sn2->local_GPs);
1260         xpc_vars_part_sn2[partid].openclose_args_pa =
1261             xp_pa(part_sn2->local_openclose_args);
1262         xpc_vars_part_sn2[partid].chctl_amo_pa =
1263             xp_pa(part_sn2->local_chctl_amo_va);
1264         cpuid = raw_smp_processor_id(); /* any CPU in this partition will do */
1265         xpc_vars_part_sn2[partid].notify_IRQ_nasid = cpuid_to_nasid(cpuid);
1266         xpc_vars_part_sn2[partid].notify_IRQ_phys_cpuid =
1267             cpu_physical_id(cpuid);
1268         xpc_vars_part_sn2[partid].nchannels = part->nchannels;
1269         xpc_vars_part_sn2[partid].magic = XPC_VP_MAGIC1_SN2;
1270
1271         return xpSuccess;
1272
1273         /* setup of ch structures failed */
1274 out_3:
1275         kfree(part_sn2->local_openclose_args_base);
1276         part_sn2->local_openclose_args = NULL;
1277 out_2:
1278         kfree(part_sn2->remote_GPs_base);
1279         part_sn2->remote_GPs = NULL;
1280 out_1:
1281         kfree(part_sn2->local_GPs_base);
1282         part_sn2->local_GPs = NULL;
1283         return retval;
1284 }
1285
1286 /*
1287  * Teardown the channel structures that are sn2 specific.
1288  */
1289 static void
1290 xpc_teardown_ch_structures_sn2(struct xpc_partition *part)
1291 {
1292         struct xpc_partition_sn2 *part_sn2 = &part->sn.sn2;
1293         short partid = XPC_PARTID(part);
1294
1295         /*
1296          * Indicate that the variables specific to the remote partition are no
1297          * longer available for its use.
1298          */
1299         xpc_vars_part_sn2[partid].magic = 0;
1300
1301         /* in case we've still got outstanding timers registered... */
1302         del_timer_sync(&part_sn2->dropped_notify_IRQ_timer);
1303         free_irq(SGI_XPC_NOTIFY, (void *)(u64)partid);
1304
1305         kfree(part_sn2->local_openclose_args_base);
1306         part_sn2->local_openclose_args = NULL;
1307         kfree(part_sn2->remote_GPs_base);
1308         part_sn2->remote_GPs = NULL;
1309         kfree(part_sn2->local_GPs_base);
1310         part_sn2->local_GPs = NULL;
1311         part_sn2->local_chctl_amo_va = NULL;
1312 }
1313
1314 /*
1315  * Create a wrapper that hides the underlying mechanism for pulling a cacheline
1316  * (or multiple cachelines) from a remote partition.
1317  *
1318  * src_pa must be a cacheline aligned physical address on the remote partition.
1319  * dst must be a cacheline aligned virtual address on this partition.
1320  * cnt must be cacheline sized
1321  */
1322 /* ??? Replace this function by call to xp_remote_memcpy() or bte_copy()? */
1323 static enum xp_retval
1324 xpc_pull_remote_cachelines_sn2(struct xpc_partition *part, void *dst,
1325                                const unsigned long src_pa, size_t cnt)
1326 {
1327         enum xp_retval ret;
1328
1329         DBUG_ON(src_pa != L1_CACHE_ALIGN(src_pa));
1330         DBUG_ON((unsigned long)dst != L1_CACHE_ALIGN((unsigned long)dst));
1331         DBUG_ON(cnt != L1_CACHE_ALIGN(cnt));
1332
1333         if (part->act_state == XPC_P_AS_DEACTIVATING)
1334                 return part->reason;
1335
1336         ret = xp_remote_memcpy(xp_pa(dst), src_pa, cnt);
1337         if (ret != xpSuccess) {
1338                 dev_dbg(xpc_chan, "xp_remote_memcpy() from partition %d failed,"
1339                         " ret=%d\n", XPC_PARTID(part), ret);
1340         }
1341         return ret;
1342 }
1343
1344 /*
1345  * Pull the remote per partition specific variables from the specified
1346  * partition.
1347  */
1348 static enum xp_retval
1349 xpc_pull_remote_vars_part_sn2(struct xpc_partition *part)
1350 {
1351         struct xpc_partition_sn2 *part_sn2 = &part->sn.sn2;
1352         u8 buffer[L1_CACHE_BYTES * 2];
1353         struct xpc_vars_part_sn2 *pulled_entry_cacheline =
1354             (struct xpc_vars_part_sn2 *)L1_CACHE_ALIGN((u64)buffer);
1355         struct xpc_vars_part_sn2 *pulled_entry;
1356         unsigned long remote_entry_cacheline_pa;
1357         unsigned long remote_entry_pa;
1358         short partid = XPC_PARTID(part);
1359         enum xp_retval ret;
1360
1361         /* pull the cacheline that contains the variables we're interested in */
1362
1363         DBUG_ON(part_sn2->remote_vars_part_pa !=
1364                 L1_CACHE_ALIGN(part_sn2->remote_vars_part_pa));
1365         DBUG_ON(sizeof(struct xpc_vars_part_sn2) != L1_CACHE_BYTES / 2);
1366
1367         remote_entry_pa = part_sn2->remote_vars_part_pa +
1368             sn_partition_id * sizeof(struct xpc_vars_part_sn2);
1369
1370         remote_entry_cacheline_pa = (remote_entry_pa & ~(L1_CACHE_BYTES - 1));
1371
1372         pulled_entry = (struct xpc_vars_part_sn2 *)((u64)pulled_entry_cacheline
1373                                                     + (remote_entry_pa &
1374                                                     (L1_CACHE_BYTES - 1)));
1375
1376         ret = xpc_pull_remote_cachelines_sn2(part, pulled_entry_cacheline,
1377                                              remote_entry_cacheline_pa,
1378                                              L1_CACHE_BYTES);
1379         if (ret != xpSuccess) {
1380                 dev_dbg(xpc_chan, "failed to pull XPC vars_part from "
1381                         "partition %d, ret=%d\n", partid, ret);
1382                 return ret;
1383         }
1384
1385         /* see if they've been set up yet */
1386
1387         if (pulled_entry->magic != XPC_VP_MAGIC1_SN2 &&
1388             pulled_entry->magic != XPC_VP_MAGIC2_SN2) {
1389
1390                 if (pulled_entry->magic != 0) {
1391                         dev_dbg(xpc_chan, "partition %d's XPC vars_part for "
1392                                 "partition %d has bad magic value (=0x%llx)\n",
1393                                 partid, sn_partition_id, pulled_entry->magic);
1394                         return xpBadMagic;
1395                 }
1396
1397                 /* they've not been initialized yet */
1398                 return xpRetry;
1399         }
1400
1401         if (xpc_vars_part_sn2[partid].magic == XPC_VP_MAGIC1_SN2) {
1402
1403                 /* validate the variables */
1404
1405                 if (pulled_entry->GPs_pa == 0 ||
1406                     pulled_entry->openclose_args_pa == 0 ||
1407                     pulled_entry->chctl_amo_pa == 0) {
1408
1409                         dev_err(xpc_chan, "partition %d's XPC vars_part for "
1410                                 "partition %d are not valid\n", partid,
1411                                 sn_partition_id);
1412                         return xpInvalidAddress;
1413                 }
1414
1415                 /* the variables we imported look to be valid */
1416
1417                 part_sn2->remote_GPs_pa = pulled_entry->GPs_pa;
1418                 part_sn2->remote_openclose_args_pa =
1419                     pulled_entry->openclose_args_pa;
1420                 part_sn2->remote_chctl_amo_va =
1421                     (struct amo *)__va(pulled_entry->chctl_amo_pa);
1422                 part_sn2->notify_IRQ_nasid = pulled_entry->notify_IRQ_nasid;
1423                 part_sn2->notify_IRQ_phys_cpuid =
1424                     pulled_entry->notify_IRQ_phys_cpuid;
1425
1426                 if (part->nchannels > pulled_entry->nchannels)
1427                         part->nchannels = pulled_entry->nchannels;
1428
1429                 /* let the other side know that we've pulled their variables */
1430
1431                 xpc_vars_part_sn2[partid].magic = XPC_VP_MAGIC2_SN2;
1432         }
1433
1434         if (pulled_entry->magic == XPC_VP_MAGIC1_SN2)
1435                 return xpRetry;
1436
1437         return xpSuccess;
1438 }
1439
1440 /*
1441  * Establish first contact with the remote partititon. This involves pulling
1442  * the XPC per partition variables from the remote partition and waiting for
1443  * the remote partition to pull ours.
1444  */
1445 static enum xp_retval
1446 xpc_make_first_contact_sn2(struct xpc_partition *part)
1447 {
1448         struct xpc_partition_sn2 *part_sn2 = &part->sn.sn2;
1449         enum xp_retval ret;
1450
1451         /*
1452          * Register the remote partition's amos with SAL so it can handle
1453          * and cleanup errors within that address range should the remote
1454          * partition go down. We don't unregister this range because it is
1455          * difficult to tell when outstanding writes to the remote partition
1456          * are finished and thus when it is safe to unregister. This should
1457          * not result in wasted space in the SAL xp_addr_region table because
1458          * we should get the same page for remote_amos_page_pa after module
1459          * reloads and system reboots.
1460          */
1461         if (sn_register_xp_addr_region(part_sn2->remote_amos_page_pa,
1462                                        PAGE_SIZE, 1) < 0) {
1463                 dev_warn(xpc_part, "xpc_activating(%d) failed to register "
1464                          "xp_addr region\n", XPC_PARTID(part));
1465
1466                 ret = xpPhysAddrRegFailed;
1467                 XPC_DEACTIVATE_PARTITION(part, ret);
1468                 return ret;
1469         }
1470
1471         /*
1472          * Send activate IRQ to get other side to activate if they've not
1473          * already begun to do so.
1474          */
1475         xpc_send_activate_IRQ_sn2(part_sn2->remote_amos_page_pa,
1476                                   cnodeid_to_nasid(0),
1477                                   part_sn2->activate_IRQ_nasid,
1478                                   part_sn2->activate_IRQ_phys_cpuid);
1479
1480         while ((ret = xpc_pull_remote_vars_part_sn2(part)) != xpSuccess) {
1481                 if (ret != xpRetry) {
1482                         XPC_DEACTIVATE_PARTITION(part, ret);
1483                         return ret;
1484                 }
1485
1486                 dev_dbg(xpc_part, "waiting to make first contact with "
1487                         "partition %d\n", XPC_PARTID(part));
1488
1489                 /* wait a 1/4 of a second or so */
1490                 (void)msleep_interruptible(250);
1491
1492                 if (part->act_state == XPC_P_AS_DEACTIVATING)
1493                         return part->reason;
1494         }
1495
1496         return xpSuccess;
1497 }
1498
1499 /*
1500  * Get the chctl flags and pull the openclose args and/or remote GPs as needed.
1501  */
1502 static u64
1503 xpc_get_chctl_all_flags_sn2(struct xpc_partition *part)
1504 {
1505         struct xpc_partition_sn2 *part_sn2 = &part->sn.sn2;
1506         unsigned long irq_flags;
1507         union xpc_channel_ctl_flags chctl;
1508         enum xp_retval ret;
1509
1510         /*
1511          * See if there are any chctl flags to be handled.
1512          */
1513
1514         spin_lock_irqsave(&part->chctl_lock, irq_flags);
1515         chctl = part->chctl;
1516         if (chctl.all_flags != 0)
1517                 part->chctl.all_flags = 0;
1518
1519         spin_unlock_irqrestore(&part->chctl_lock, irq_flags);
1520
1521         if (xpc_any_openclose_chctl_flags_set(&chctl)) {
1522                 ret = xpc_pull_remote_cachelines_sn2(part, part->
1523                                                      remote_openclose_args,
1524                                                      part_sn2->
1525                                                      remote_openclose_args_pa,
1526                                                      XPC_OPENCLOSE_ARGS_SIZE);
1527                 if (ret != xpSuccess) {
1528                         XPC_DEACTIVATE_PARTITION(part, ret);
1529
1530                         dev_dbg(xpc_chan, "failed to pull openclose args from "
1531                                 "partition %d, ret=%d\n", XPC_PARTID(part),
1532                                 ret);
1533
1534                         /* don't bother processing chctl flags anymore */
1535                         chctl.all_flags = 0;
1536                 }
1537         }
1538
1539         if (xpc_any_msg_chctl_flags_set(&chctl)) {
1540                 ret = xpc_pull_remote_cachelines_sn2(part, part_sn2->remote_GPs,
1541                                                      part_sn2->remote_GPs_pa,
1542                                                      XPC_GP_SIZE);
1543                 if (ret != xpSuccess) {
1544                         XPC_DEACTIVATE_PARTITION(part, ret);
1545
1546                         dev_dbg(xpc_chan, "failed to pull GPs from partition "
1547                                 "%d, ret=%d\n", XPC_PARTID(part), ret);
1548
1549                         /* don't bother processing chctl flags anymore */
1550                         chctl.all_flags = 0;
1551                 }
1552         }
1553
1554         return chctl.all_flags;
1555 }
1556
1557 /*
1558  * Allocate the local message queue and the notify queue.
1559  */
1560 static enum xp_retval
1561 xpc_allocate_local_msgqueue_sn2(struct xpc_channel *ch)
1562 {
1563         struct xpc_channel_sn2 *ch_sn2 = &ch->sn.sn2;
1564         unsigned long irq_flags;
1565         int nentries;
1566         size_t nbytes;
1567
1568         for (nentries = ch->local_nentries; nentries > 0; nentries--) {
1569
1570                 nbytes = nentries * ch->entry_size;
1571                 ch_sn2->local_msgqueue =
1572                     xpc_kzalloc_cacheline_aligned(nbytes, GFP_KERNEL,
1573                                                   &ch_sn2->local_msgqueue_base);
1574                 if (ch_sn2->local_msgqueue == NULL)
1575                         continue;
1576
1577                 nbytes = nentries * sizeof(struct xpc_notify_sn2);
1578                 ch_sn2->notify_queue = kzalloc(nbytes, GFP_KERNEL);
1579                 if (ch_sn2->notify_queue == NULL) {
1580                         kfree(ch_sn2->local_msgqueue_base);
1581                         ch_sn2->local_msgqueue = NULL;
1582                         continue;
1583                 }
1584
1585                 spin_lock_irqsave(&ch->lock, irq_flags);
1586                 if (nentries < ch->local_nentries) {
1587                         dev_dbg(xpc_chan, "nentries=%d local_nentries=%d, "
1588                                 "partid=%d, channel=%d\n", nentries,
1589                                 ch->local_nentries, ch->partid, ch->number);
1590
1591                         ch->local_nentries = nentries;
1592                 }
1593                 spin_unlock_irqrestore(&ch->lock, irq_flags);
1594                 return xpSuccess;
1595         }
1596
1597         dev_dbg(xpc_chan, "can't get memory for local message queue and notify "
1598                 "queue, partid=%d, channel=%d\n", ch->partid, ch->number);
1599         return xpNoMemory;
1600 }
1601
1602 /*
1603  * Allocate the cached remote message queue.
1604  */
1605 static enum xp_retval
1606 xpc_allocate_remote_msgqueue_sn2(struct xpc_channel *ch)
1607 {
1608         struct xpc_channel_sn2 *ch_sn2 = &ch->sn.sn2;
1609         unsigned long irq_flags;
1610         int nentries;
1611         size_t nbytes;
1612
1613         DBUG_ON(ch->remote_nentries <= 0);
1614
1615         for (nentries = ch->remote_nentries; nentries > 0; nentries--) {
1616
1617                 nbytes = nentries * ch->entry_size;
1618                 ch_sn2->remote_msgqueue =
1619                     xpc_kzalloc_cacheline_aligned(nbytes, GFP_KERNEL, &ch_sn2->
1620                                                   remote_msgqueue_base);
1621                 if (ch_sn2->remote_msgqueue == NULL)
1622                         continue;
1623
1624                 spin_lock_irqsave(&ch->lock, irq_flags);
1625                 if (nentries < ch->remote_nentries) {
1626                         dev_dbg(xpc_chan, "nentries=%d remote_nentries=%d, "
1627                                 "partid=%d, channel=%d\n", nentries,
1628                                 ch->remote_nentries, ch->partid, ch->number);
1629
1630                         ch->remote_nentries = nentries;
1631                 }
1632                 spin_unlock_irqrestore(&ch->lock, irq_flags);
1633                 return xpSuccess;
1634         }
1635
1636         dev_dbg(xpc_chan, "can't get memory for cached remote message queue, "
1637                 "partid=%d, channel=%d\n", ch->partid, ch->number);
1638         return xpNoMemory;
1639 }
1640
1641 /*
1642  * Allocate message queues and other stuff associated with a channel.
1643  *
1644  * Note: Assumes all of the channel sizes are filled in.
1645  */
1646 static enum xp_retval
1647 xpc_setup_msg_structures_sn2(struct xpc_channel *ch)
1648 {
1649         struct xpc_channel_sn2 *ch_sn2 = &ch->sn.sn2;
1650         enum xp_retval ret;
1651
1652         DBUG_ON(ch->flags & XPC_C_SETUP);
1653
1654         ret = xpc_allocate_local_msgqueue_sn2(ch);
1655         if (ret == xpSuccess) {
1656
1657                 ret = xpc_allocate_remote_msgqueue_sn2(ch);
1658                 if (ret != xpSuccess) {
1659                         kfree(ch_sn2->local_msgqueue_base);
1660                         ch_sn2->local_msgqueue = NULL;
1661                         kfree(ch_sn2->notify_queue);
1662                         ch_sn2->notify_queue = NULL;
1663                 }
1664         }
1665         return ret;
1666 }
1667
1668 /*
1669  * Free up message queues and other stuff that were allocated for the specified
1670  * channel.
1671  */
1672 static void
1673 xpc_teardown_msg_structures_sn2(struct xpc_channel *ch)
1674 {
1675         struct xpc_channel_sn2 *ch_sn2 = &ch->sn.sn2;
1676
1677         DBUG_ON(!spin_is_locked(&ch->lock));
1678
1679         ch_sn2->remote_msgqueue_pa = 0;
1680
1681         ch_sn2->local_GP->get = 0;
1682         ch_sn2->local_GP->put = 0;
1683         ch_sn2->remote_GP.get = 0;
1684         ch_sn2->remote_GP.put = 0;
1685         ch_sn2->w_local_GP.get = 0;
1686         ch_sn2->w_local_GP.put = 0;
1687         ch_sn2->w_remote_GP.get = 0;
1688         ch_sn2->w_remote_GP.put = 0;
1689         ch_sn2->next_msg_to_pull = 0;
1690
1691         if (ch->flags & XPC_C_SETUP) {
1692                 dev_dbg(xpc_chan, "ch->flags=0x%x, partid=%d, channel=%d\n",
1693                         ch->flags, ch->partid, ch->number);
1694
1695                 kfree(ch_sn2->local_msgqueue_base);
1696                 ch_sn2->local_msgqueue = NULL;
1697                 kfree(ch_sn2->remote_msgqueue_base);
1698                 ch_sn2->remote_msgqueue = NULL;
1699                 kfree(ch_sn2->notify_queue);
1700                 ch_sn2->notify_queue = NULL;
1701         }
1702 }
1703
1704 /*
1705  * Notify those who wanted to be notified upon delivery of their message.
1706  */
1707 static void
1708 xpc_notify_senders_sn2(struct xpc_channel *ch, enum xp_retval reason, s64 put)
1709 {
1710         struct xpc_notify_sn2 *notify;
1711         u8 notify_type;
1712         s64 get = ch->sn.sn2.w_remote_GP.get - 1;
1713
1714         while (++get < put && atomic_read(&ch->n_to_notify) > 0) {
1715
1716                 notify = &ch->sn.sn2.notify_queue[get % ch->local_nentries];
1717
1718                 /*
1719                  * See if the notify entry indicates it was associated with
1720                  * a message who's sender wants to be notified. It is possible
1721                  * that it is, but someone else is doing or has done the
1722                  * notification.
1723                  */
1724                 notify_type = notify->type;
1725                 if (notify_type == 0 ||
1726                     cmpxchg(&notify->type, notify_type, 0) != notify_type) {
1727                         continue;
1728                 }
1729
1730                 DBUG_ON(notify_type != XPC_N_CALL);
1731
1732                 atomic_dec(&ch->n_to_notify);
1733
1734                 if (notify->func != NULL) {
1735                         dev_dbg(xpc_chan, "notify->func() called, notify=0x%p "
1736                                 "msg_number=%lld partid=%d channel=%d\n",
1737                                 (void *)notify, get, ch->partid, ch->number);
1738
1739                         notify->func(reason, ch->partid, ch->number,
1740                                      notify->key);
1741
1742                         dev_dbg(xpc_chan, "notify->func() returned, notify=0x%p"
1743                                 " msg_number=%lld partid=%d channel=%d\n",
1744                                 (void *)notify, get, ch->partid, ch->number);
1745                 }
1746         }
1747 }
1748
1749 static void
1750 xpc_notify_senders_of_disconnect_sn2(struct xpc_channel *ch)
1751 {
1752         xpc_notify_senders_sn2(ch, ch->reason, ch->sn.sn2.w_local_GP.put);
1753 }
1754
1755 /*
1756  * Clear some of the msg flags in the local message queue.
1757  */
1758 static inline void
1759 xpc_clear_local_msgqueue_flags_sn2(struct xpc_channel *ch)
1760 {
1761         struct xpc_channel_sn2 *ch_sn2 = &ch->sn.sn2;
1762         struct xpc_msg_sn2 *msg;
1763         s64 get;
1764
1765         get = ch_sn2->w_remote_GP.get;
1766         do {
1767                 msg = (struct xpc_msg_sn2 *)((u64)ch_sn2->local_msgqueue +
1768                                              (get % ch->local_nentries) *
1769                                              ch->entry_size);
1770                 DBUG_ON(!(msg->flags & XPC_M_SN2_READY));
1771                 msg->flags = 0;
1772         } while (++get < ch_sn2->remote_GP.get);
1773 }
1774
1775 /*
1776  * Clear some of the msg flags in the remote message queue.
1777  */
1778 static inline void
1779 xpc_clear_remote_msgqueue_flags_sn2(struct xpc_channel *ch)
1780 {
1781         struct xpc_channel_sn2 *ch_sn2 = &ch->sn.sn2;
1782         struct xpc_msg_sn2 *msg;
1783         s64 put, remote_nentries = ch->remote_nentries;
1784
1785         /* flags are zeroed when the buffer is allocated */
1786         if (ch_sn2->remote_GP.put < remote_nentries)
1787                 return;
1788
1789         put = max(ch_sn2->w_remote_GP.put, remote_nentries);
1790         do {
1791                 msg = (struct xpc_msg_sn2 *)((u64)ch_sn2->remote_msgqueue +
1792                                              (put % remote_nentries) *
1793                                              ch->entry_size);
1794                 DBUG_ON(!(msg->flags & XPC_M_SN2_READY));
1795                 DBUG_ON(!(msg->flags & XPC_M_SN2_DONE));
1796                 DBUG_ON(msg->number != put - remote_nentries);
1797                 msg->flags = 0;
1798         } while (++put < ch_sn2->remote_GP.put);
1799 }
1800
1801 static int
1802 xpc_n_of_deliverable_payloads_sn2(struct xpc_channel *ch)
1803 {
1804         return ch->sn.sn2.w_remote_GP.put - ch->sn.sn2.w_local_GP.get;
1805 }
1806
1807 static void
1808 xpc_process_msg_chctl_flags_sn2(struct xpc_partition *part, int ch_number)
1809 {
1810         struct xpc_channel *ch = &part->channels[ch_number];
1811         struct xpc_channel_sn2 *ch_sn2 = &ch->sn.sn2;
1812         int npayloads_sent;
1813
1814         ch_sn2->remote_GP = part->sn.sn2.remote_GPs[ch_number];
1815
1816         /* See what, if anything, has changed for each connected channel */
1817
1818         xpc_msgqueue_ref(ch);
1819
1820         if (ch_sn2->w_remote_GP.get == ch_sn2->remote_GP.get &&
1821             ch_sn2->w_remote_GP.put == ch_sn2->remote_GP.put) {
1822                 /* nothing changed since GPs were last pulled */
1823                 xpc_msgqueue_deref(ch);
1824                 return;
1825         }
1826
1827         if (!(ch->flags & XPC_C_CONNECTED)) {
1828                 xpc_msgqueue_deref(ch);
1829                 return;
1830         }
1831
1832         /*
1833          * First check to see if messages recently sent by us have been
1834          * received by the other side. (The remote GET value will have
1835          * changed since we last looked at it.)
1836          */
1837
1838         if (ch_sn2->w_remote_GP.get != ch_sn2->remote_GP.get) {
1839
1840                 /*
1841                  * We need to notify any senders that want to be notified
1842                  * that their sent messages have been received by their
1843                  * intended recipients. We need to do this before updating
1844                  * w_remote_GP.get so that we don't allocate the same message
1845                  * queue entries prematurely (see xpc_allocate_msg()).
1846                  */
1847                 if (atomic_read(&ch->n_to_notify) > 0) {
1848                         /*
1849                          * Notify senders that messages sent have been
1850                          * received and delivered by the other side.
1851                          */
1852                         xpc_notify_senders_sn2(ch, xpMsgDelivered,
1853                                                ch_sn2->remote_GP.get);
1854                 }
1855
1856                 /*
1857                  * Clear msg->flags in previously sent messages, so that
1858                  * they're ready for xpc_allocate_msg().
1859                  */
1860                 xpc_clear_local_msgqueue_flags_sn2(ch);
1861
1862                 ch_sn2->w_remote_GP.get = ch_sn2->remote_GP.get;
1863
1864                 dev_dbg(xpc_chan, "w_remote_GP.get changed to %lld, partid=%d, "
1865                         "channel=%d\n", ch_sn2->w_remote_GP.get, ch->partid,
1866                         ch->number);
1867
1868                 /*
1869                  * If anyone was waiting for message queue entries to become
1870                  * available, wake them up.
1871                  */
1872                 if (atomic_read(&ch->n_on_msg_allocate_wq) > 0)
1873                         wake_up(&ch->msg_allocate_wq);
1874         }
1875
1876         /*
1877          * Now check for newly sent messages by the other side. (The remote
1878          * PUT value will have changed since we last looked at it.)
1879          */
1880
1881         if (ch_sn2->w_remote_GP.put != ch_sn2->remote_GP.put) {
1882                 /*
1883                  * Clear msg->flags in previously received messages, so that
1884                  * they're ready for xpc_get_deliverable_payload_sn2().
1885                  */
1886                 xpc_clear_remote_msgqueue_flags_sn2(ch);
1887
1888                 smp_wmb(); /* ensure flags have been cleared before bte_copy */
1889                 ch_sn2->w_remote_GP.put = ch_sn2->remote_GP.put;
1890
1891                 dev_dbg(xpc_chan, "w_remote_GP.put changed to %lld, partid=%d, "
1892                         "channel=%d\n", ch_sn2->w_remote_GP.put, ch->partid,
1893                         ch->number);
1894
1895                 npayloads_sent = xpc_n_of_deliverable_payloads_sn2(ch);
1896                 if (npayloads_sent > 0) {
1897                         dev_dbg(xpc_chan, "msgs waiting to be copied and "
1898                                 "delivered=%d, partid=%d, channel=%d\n",
1899                                 npayloads_sent, ch->partid, ch->number);
1900
1901                         if (ch->flags & XPC_C_CONNECTEDCALLOUT_MADE)
1902                                 xpc_activate_kthreads(ch, npayloads_sent);
1903                 }
1904         }
1905
1906         xpc_msgqueue_deref(ch);
1907 }
1908
1909 static struct xpc_msg_sn2 *
1910 xpc_pull_remote_msg_sn2(struct xpc_channel *ch, s64 get)
1911 {
1912         struct xpc_partition *part = &xpc_partitions[ch->partid];
1913         struct xpc_channel_sn2 *ch_sn2 = &ch->sn.sn2;
1914         unsigned long remote_msg_pa;
1915         struct xpc_msg_sn2 *msg;
1916         u32 msg_index;
1917         u32 nmsgs;
1918         u64 msg_offset;
1919         enum xp_retval ret;
1920
1921         if (mutex_lock_interruptible(&ch_sn2->msg_to_pull_mutex) != 0) {
1922                 /* we were interrupted by a signal */
1923                 return NULL;
1924         }
1925
1926         while (get >= ch_sn2->next_msg_to_pull) {
1927
1928                 /* pull as many messages as are ready and able to be pulled */
1929
1930                 msg_index = ch_sn2->next_msg_to_pull % ch->remote_nentries;
1931
1932                 DBUG_ON(ch_sn2->next_msg_to_pull >= ch_sn2->w_remote_GP.put);
1933                 nmsgs = ch_sn2->w_remote_GP.put - ch_sn2->next_msg_to_pull;
1934                 if (msg_index + nmsgs > ch->remote_nentries) {
1935                         /* ignore the ones that wrap the msg queue for now */
1936                         nmsgs = ch->remote_nentries - msg_index;
1937                 }
1938
1939                 msg_offset = msg_index * ch->entry_size;
1940                 msg = (struct xpc_msg_sn2 *)((u64)ch_sn2->remote_msgqueue +
1941                     msg_offset);
1942                 remote_msg_pa = ch_sn2->remote_msgqueue_pa + msg_offset;
1943
1944                 ret = xpc_pull_remote_cachelines_sn2(part, msg, remote_msg_pa,
1945                                                      nmsgs * ch->entry_size);
1946                 if (ret != xpSuccess) {
1947
1948                         dev_dbg(xpc_chan, "failed to pull %d msgs starting with"
1949                                 " msg %lld from partition %d, channel=%d, "
1950                                 "ret=%d\n", nmsgs, ch_sn2->next_msg_to_pull,
1951                                 ch->partid, ch->number, ret);
1952
1953                         XPC_DEACTIVATE_PARTITION(part, ret);
1954
1955                         mutex_unlock(&ch_sn2->msg_to_pull_mutex);
1956                         return NULL;
1957                 }
1958
1959                 ch_sn2->next_msg_to_pull += nmsgs;
1960         }
1961
1962         mutex_unlock(&ch_sn2->msg_to_pull_mutex);
1963
1964         /* return the message we were looking for */
1965         msg_offset = (get % ch->remote_nentries) * ch->entry_size;
1966         msg = (struct xpc_msg_sn2 *)((u64)ch_sn2->remote_msgqueue + msg_offset);
1967
1968         return msg;
1969 }
1970
1971 /*
1972  * Get the next deliverable message's payload.
1973  */
1974 static void *
1975 xpc_get_deliverable_payload_sn2(struct xpc_channel *ch)
1976 {
1977         struct xpc_channel_sn2 *ch_sn2 = &ch->sn.sn2;
1978         struct xpc_msg_sn2 *msg;
1979         void *payload = NULL;
1980         s64 get;
1981
1982         do {
1983                 if (ch->flags & XPC_C_DISCONNECTING)
1984                         break;
1985
1986                 get = ch_sn2->w_local_GP.get;
1987                 smp_rmb();      /* guarantee that .get loads before .put */
1988                 if (get == ch_sn2->w_remote_GP.put)
1989                         break;
1990
1991                 /* There are messages waiting to be pulled and delivered.
1992                  * We need to try to secure one for ourselves. We'll do this
1993                  * by trying to increment w_local_GP.get and hope that no one
1994                  * else beats us to it. If they do, we'll we'll simply have
1995                  * to try again for the next one.
1996                  */
1997
1998                 if (cmpxchg(&ch_sn2->w_local_GP.get, get, get + 1) == get) {
1999                         /* we got the entry referenced by get */
2000
2001                         dev_dbg(xpc_chan, "w_local_GP.get changed to %lld, "
2002                                 "partid=%d, channel=%d\n", get + 1,
2003                                 ch->partid, ch->number);
2004
2005                         /* pull the message from the remote partition */
2006
2007                         msg = xpc_pull_remote_msg_sn2(ch, get);
2008
2009                         if (msg != NULL) {
2010                                 DBUG_ON(msg->number != get);
2011                                 DBUG_ON(msg->flags & XPC_M_SN2_DONE);
2012                                 DBUG_ON(!(msg->flags & XPC_M_SN2_READY));
2013
2014                                 payload = &msg->payload;
2015                         }
2016                         break;
2017                 }
2018
2019         } while (1);
2020
2021         return payload;
2022 }
2023
2024 /*
2025  * Now we actually send the messages that are ready to be sent by advancing
2026  * the local message queue's Put value and then send a chctl msgrequest to the
2027  * recipient partition.
2028  */
2029 static void
2030 xpc_send_msgs_sn2(struct xpc_channel *ch, s64 initial_put)
2031 {
2032         struct xpc_channel_sn2 *ch_sn2 = &ch->sn.sn2;
2033         struct xpc_msg_sn2 *msg;
2034         s64 put = initial_put + 1;
2035         int send_msgrequest = 0;
2036
2037         while (1) {
2038
2039                 while (1) {
2040                         if (put == ch_sn2->w_local_GP.put)
2041                                 break;
2042
2043                         msg = (struct xpc_msg_sn2 *)((u64)ch_sn2->
2044                                                      local_msgqueue + (put %
2045                                                      ch->local_nentries) *
2046                                                      ch->entry_size);
2047
2048                         if (!(msg->flags & XPC_M_SN2_READY))
2049                                 break;
2050
2051                         put++;
2052                 }
2053
2054                 if (put == initial_put) {
2055                         /* nothing's changed */
2056                         break;
2057                 }
2058
2059                 if (cmpxchg_rel(&ch_sn2->local_GP->put, initial_put, put) !=
2060                     initial_put) {
2061                         /* someone else beat us to it */
2062                         DBUG_ON(ch_sn2->local_GP->put < initial_put);
2063                         break;
2064                 }
2065
2066                 /* we just set the new value of local_GP->put */
2067
2068                 dev_dbg(xpc_chan, "local_GP->put changed to %lld, partid=%d, "
2069                         "channel=%d\n", put, ch->partid, ch->number);
2070
2071                 send_msgrequest = 1;
2072
2073                 /*
2074                  * We need to ensure that the message referenced by
2075                  * local_GP->put is not XPC_M_SN2_READY or that local_GP->put
2076                  * equals w_local_GP.put, so we'll go have a look.
2077                  */
2078                 initial_put = put;
2079         }
2080
2081         if (send_msgrequest)
2082                 xpc_send_chctl_msgrequest_sn2(ch);
2083 }
2084
2085 /*
2086  * Allocate an entry for a message from the message queue associated with the
2087  * specified channel.
2088  */
2089 static enum xp_retval
2090 xpc_allocate_msg_sn2(struct xpc_channel *ch, u32 flags,
2091                      struct xpc_msg_sn2 **address_of_msg)
2092 {
2093         struct xpc_channel_sn2 *ch_sn2 = &ch->sn.sn2;
2094         struct xpc_msg_sn2 *msg;
2095         enum xp_retval ret;
2096         s64 put;
2097
2098         /*
2099          * Get the next available message entry from the local message queue.
2100          * If none are available, we'll make sure that we grab the latest
2101          * GP values.
2102          */
2103         ret = xpTimeout;
2104
2105         while (1) {
2106
2107                 put = ch_sn2->w_local_GP.put;
2108                 smp_rmb();      /* guarantee that .put loads before .get */
2109                 if (put - ch_sn2->w_remote_GP.get < ch->local_nentries) {
2110
2111                         /* There are available message entries. We need to try
2112                          * to secure one for ourselves. We'll do this by trying
2113                          * to increment w_local_GP.put as long as someone else
2114                          * doesn't beat us to it. If they do, we'll have to
2115                          * try again.
2116                          */
2117                         if (cmpxchg(&ch_sn2->w_local_GP.put, put, put + 1) ==
2118                             put) {
2119                                 /* we got the entry referenced by put */
2120                                 break;
2121                         }
2122                         continue;       /* try again */
2123                 }
2124
2125                 /*
2126                  * There aren't any available msg entries at this time.
2127                  *
2128                  * In waiting for a message entry to become available,
2129                  * we set a timeout in case the other side is not sending
2130                  * completion interrupts. This lets us fake a notify IRQ
2131                  * that will cause the notify IRQ handler to fetch the latest
2132                  * GP values as if an interrupt was sent by the other side.
2133                  */
2134                 if (ret == xpTimeout)
2135                         xpc_send_chctl_local_msgrequest_sn2(ch);
2136
2137                 if (flags & XPC_NOWAIT)
2138                         return xpNoWait;
2139
2140                 ret = xpc_allocate_msg_wait(ch);
2141                 if (ret != xpInterrupted && ret != xpTimeout)
2142                         return ret;
2143         }
2144
2145         /* get the message's address and initialize it */
2146         msg = (struct xpc_msg_sn2 *)((u64)ch_sn2->local_msgqueue +
2147                                      (put % ch->local_nentries) *
2148                                      ch->entry_size);
2149
2150         DBUG_ON(msg->flags != 0);
2151         msg->number = put;
2152
2153         dev_dbg(xpc_chan, "w_local_GP.put changed to %lld; msg=0x%p, "
2154                 "msg_number=%lld, partid=%d, channel=%d\n", put + 1,
2155                 (void *)msg, msg->number, ch->partid, ch->number);
2156
2157         *address_of_msg = msg;
2158         return xpSuccess;
2159 }
2160
2161 /*
2162  * Common code that does the actual sending of the message by advancing the
2163  * local message queue's Put value and sends a chctl msgrequest to the
2164  * partition the message is being sent to.
2165  */
2166 static enum xp_retval
2167 xpc_send_payload_sn2(struct xpc_channel *ch, u32 flags, void *payload,
2168                      u16 payload_size, u8 notify_type, xpc_notify_func func,
2169                      void *key)
2170 {
2171         enum xp_retval ret = xpSuccess;
2172         struct xpc_channel_sn2 *ch_sn2 = &ch->sn.sn2;
2173         struct xpc_msg_sn2 *msg = msg;
2174         struct xpc_notify_sn2 *notify = notify;
2175         s64 msg_number;
2176         s64 put;
2177
2178         DBUG_ON(notify_type == XPC_N_CALL && func == NULL);
2179
2180         if (XPC_MSG_SIZE(payload_size) > ch->entry_size)
2181                 return xpPayloadTooBig;
2182
2183         xpc_msgqueue_ref(ch);
2184
2185         if (ch->flags & XPC_C_DISCONNECTING) {
2186                 ret = ch->reason;
2187                 goto out_1;
2188         }
2189         if (!(ch->flags & XPC_C_CONNECTED)) {
2190                 ret = xpNotConnected;
2191                 goto out_1;
2192         }
2193
2194         ret = xpc_allocate_msg_sn2(ch, flags, &msg);
2195         if (ret != xpSuccess)
2196                 goto out_1;
2197
2198         msg_number = msg->number;
2199
2200         if (notify_type != 0) {
2201                 /*
2202                  * Tell the remote side to send an ACK interrupt when the
2203                  * message has been delivered.
2204                  */
2205                 msg->flags |= XPC_M_SN2_INTERRUPT;
2206
2207                 atomic_inc(&ch->n_to_notify);
2208
2209                 notify = &ch_sn2->notify_queue[msg_number % ch->local_nentries];
2210                 notify->func = func;
2211                 notify->key = key;
2212                 notify->type = notify_type;
2213
2214                 /* ??? Is a mb() needed here? */
2215
2216                 if (ch->flags & XPC_C_DISCONNECTING) {
2217                         /*
2218                          * An error occurred between our last error check and
2219                          * this one. We will try to clear the type field from
2220                          * the notify entry. If we succeed then
2221                          * xpc_disconnect_channel() didn't already process
2222                          * the notify entry.
2223                          */
2224                         if (cmpxchg(&notify->type, notify_type, 0) ==
2225                             notify_type) {
2226                                 atomic_dec(&ch->n_to_notify);
2227                                 ret = ch->reason;
2228                         }
2229                         goto out_1;
2230                 }
2231         }
2232
2233         memcpy(&msg->payload, payload, payload_size);
2234
2235         msg->flags |= XPC_M_SN2_READY;
2236
2237         /*
2238          * The preceding store of msg->flags must occur before the following
2239          * load of local_GP->put.
2240          */
2241         smp_mb();
2242
2243         /* see if the message is next in line to be sent, if so send it */
2244
2245         put = ch_sn2->local_GP->put;
2246         if (put == msg_number)
2247                 xpc_send_msgs_sn2(ch, put);
2248
2249 out_1:
2250         xpc_msgqueue_deref(ch);
2251         return ret;
2252 }
2253
2254 /*
2255  * Now we actually acknowledge the messages that have been delivered and ack'd
2256  * by advancing the cached remote message queue's Get value and if requested
2257  * send a chctl msgrequest to the message sender's partition.
2258  *
2259  * If a message has XPC_M_SN2_INTERRUPT set, send an interrupt to the partition
2260  * that sent the message.
2261  */
2262 static void
2263 xpc_acknowledge_msgs_sn2(struct xpc_channel *ch, s64 initial_get, u8 msg_flags)
2264 {
2265         struct xpc_channel_sn2 *ch_sn2 = &ch->sn.sn2;
2266         struct xpc_msg_sn2 *msg;
2267         s64 get = initial_get + 1;
2268         int send_msgrequest = 0;
2269
2270         while (1) {
2271
2272                 while (1) {
2273                         if (get == ch_sn2->w_local_GP.get)
2274                                 break;
2275
2276                         msg = (struct xpc_msg_sn2 *)((u64)ch_sn2->
2277                                                      remote_msgqueue + (get %
2278                                                      ch->remote_nentries) *
2279                                                      ch->entry_size);
2280
2281                         if (!(msg->flags & XPC_M_SN2_DONE))
2282                                 break;
2283
2284                         msg_flags |= msg->flags;
2285                         get++;
2286                 }
2287
2288                 if (get == initial_get) {
2289                         /* nothing's changed */
2290                         break;
2291                 }
2292
2293                 if (cmpxchg_rel(&ch_sn2->local_GP->get, initial_get, get) !=
2294                     initial_get) {
2295                         /* someone else beat us to it */
2296                         DBUG_ON(ch_sn2->local_GP->get <= initial_get);
2297                         break;
2298                 }
2299
2300                 /* we just set the new value of local_GP->get */
2301
2302                 dev_dbg(xpc_chan, "local_GP->get changed to %lld, partid=%d, "
2303                         "channel=%d\n", get, ch->partid, ch->number);
2304
2305                 send_msgrequest = (msg_flags & XPC_M_SN2_INTERRUPT);
2306
2307                 /*
2308                  * We need to ensure that the message referenced by
2309                  * local_GP->get is not XPC_M_SN2_DONE or that local_GP->get
2310                  * equals w_local_GP.get, so we'll go have a look.
2311                  */
2312                 initial_get = get;
2313         }
2314
2315         if (send_msgrequest)
2316                 xpc_send_chctl_msgrequest_sn2(ch);
2317 }
2318
2319 static void
2320 xpc_received_payload_sn2(struct xpc_channel *ch, void *payload)
2321 {
2322         struct xpc_msg_sn2 *msg;
2323         s64 msg_number;
2324         s64 get;
2325
2326         msg = container_of(payload, struct xpc_msg_sn2, payload);
2327         msg_number = msg->number;
2328
2329         dev_dbg(xpc_chan, "msg=0x%p, msg_number=%lld, partid=%d, channel=%d\n",
2330                 (void *)msg, msg_number, ch->partid, ch->number);
2331
2332         DBUG_ON((((u64)msg - (u64)ch->sn.sn2.remote_msgqueue) / ch->entry_size) !=
2333                 msg_number % ch->remote_nentries);
2334         DBUG_ON(!(msg->flags & XPC_M_SN2_READY));
2335         DBUG_ON(msg->flags & XPC_M_SN2_DONE);
2336
2337         msg->flags |= XPC_M_SN2_DONE;
2338
2339         /*
2340          * The preceding store of msg->flags must occur before the following
2341          * load of local_GP->get.
2342          */
2343         smp_mb();
2344
2345         /*
2346          * See if this message is next in line to be acknowledged as having
2347          * been delivered.
2348          */
2349         get = ch->sn.sn2.local_GP->get;
2350         if (get == msg_number)
2351                 xpc_acknowledge_msgs_sn2(ch, get, msg->flags);
2352 }
2353
2354 static struct xpc_arch_operations xpc_arch_ops_sn2 = {
2355         .setup_partitions = xpc_setup_partitions_sn2,
2356         .teardown_partitions = xpc_teardown_partitions_sn2,
2357         .process_activate_IRQ_rcvd = xpc_process_activate_IRQ_rcvd_sn2,
2358         .get_partition_rsvd_page_pa = xpc_get_partition_rsvd_page_pa_sn2,
2359         .setup_rsvd_page = xpc_setup_rsvd_page_sn2,
2360
2361         .allow_hb = xpc_allow_hb_sn2,
2362         .disallow_hb = xpc_disallow_hb_sn2,
2363         .disallow_all_hbs = xpc_disallow_all_hbs_sn2,
2364         .increment_heartbeat = xpc_increment_heartbeat_sn2,
2365         .offline_heartbeat = xpc_offline_heartbeat_sn2,
2366         .online_heartbeat = xpc_online_heartbeat_sn2,
2367         .heartbeat_init = xpc_heartbeat_init_sn2,
2368         .heartbeat_exit = xpc_heartbeat_exit_sn2,
2369         .get_remote_heartbeat = xpc_get_remote_heartbeat_sn2,
2370
2371         .request_partition_activation =
2372                 xpc_request_partition_activation_sn2,
2373         .request_partition_reactivation =
2374                 xpc_request_partition_reactivation_sn2,
2375         .request_partition_deactivation =
2376                 xpc_request_partition_deactivation_sn2,
2377         .cancel_partition_deactivation_request =
2378                 xpc_cancel_partition_deactivation_request_sn2,
2379
2380         .setup_ch_structures = xpc_setup_ch_structures_sn2,
2381         .teardown_ch_structures = xpc_teardown_ch_structures_sn2,
2382
2383         .make_first_contact = xpc_make_first_contact_sn2,
2384
2385         .get_chctl_all_flags = xpc_get_chctl_all_flags_sn2,
2386         .send_chctl_closerequest = xpc_send_chctl_closerequest_sn2,
2387         .send_chctl_closereply = xpc_send_chctl_closereply_sn2,
2388         .send_chctl_openrequest = xpc_send_chctl_openrequest_sn2,
2389         .send_chctl_openreply = xpc_send_chctl_openreply_sn2,
2390         .send_chctl_opencomplete = xpc_send_chctl_opencomplete_sn2,
2391         .process_msg_chctl_flags = xpc_process_msg_chctl_flags_sn2,
2392
2393         .save_remote_msgqueue_pa = xpc_save_remote_msgqueue_pa_sn2,
2394
2395         .setup_msg_structures = xpc_setup_msg_structures_sn2,
2396         .teardown_msg_structures = xpc_teardown_msg_structures_sn2,
2397
2398         .indicate_partition_engaged = xpc_indicate_partition_engaged_sn2,
2399         .indicate_partition_disengaged = xpc_indicate_partition_disengaged_sn2,
2400         .partition_engaged = xpc_partition_engaged_sn2,
2401         .any_partition_engaged = xpc_any_partition_engaged_sn2,
2402         .assume_partition_disengaged = xpc_assume_partition_disengaged_sn2,
2403
2404         .n_of_deliverable_payloads = xpc_n_of_deliverable_payloads_sn2,
2405         .send_payload = xpc_send_payload_sn2,
2406         .get_deliverable_payload = xpc_get_deliverable_payload_sn2,
2407         .received_payload = xpc_received_payload_sn2,
2408         .notify_senders_of_disconnect = xpc_notify_senders_of_disconnect_sn2,
2409 };
2410
2411 int
2412 xpc_init_sn2(void)
2413 {
2414         int ret;
2415         size_t buf_size;
2416
2417         xpc_arch_ops = xpc_arch_ops_sn2;
2418
2419         if (offsetof(struct xpc_msg_sn2, payload) > XPC_MSG_HDR_MAX_SIZE) {
2420                 dev_err(xpc_part, "header portion of struct xpc_msg_sn2 is "
2421                         "larger than %d\n", XPC_MSG_HDR_MAX_SIZE);
2422                 return -E2BIG;
2423         }
2424
2425         buf_size = max(XPC_RP_VARS_SIZE,
2426                        XPC_RP_HEADER_SIZE + XP_NASID_MASK_BYTES_SN2);
2427         xpc_remote_copy_buffer_sn2 = xpc_kmalloc_cacheline_aligned(buf_size,
2428                                                                    GFP_KERNEL,
2429                                               &xpc_remote_copy_buffer_base_sn2);
2430         if (xpc_remote_copy_buffer_sn2 == NULL) {
2431                 dev_err(xpc_part, "can't get memory for remote copy buffer\n");
2432                 return -ENOMEM;
2433         }
2434
2435         /* open up protections for IPI and [potentially] amo operations */
2436         xpc_allow_IPI_ops_sn2();
2437         xpc_allow_amo_ops_shub_wars_1_1_sn2();
2438
2439         /*
2440          * This is safe to do before the xpc_hb_checker thread has started
2441          * because the handler releases a wait queue.  If an interrupt is
2442          * received before the thread is waiting, it will not go to sleep,
2443          * but rather immediately process the interrupt.
2444          */
2445         ret = request_irq(SGI_XPC_ACTIVATE, xpc_handle_activate_IRQ_sn2, 0,
2446                           "xpc hb", NULL);
2447         if (ret != 0) {
2448                 dev_err(xpc_part, "can't register ACTIVATE IRQ handler, "
2449                         "errno=%d\n", -ret);
2450                 xpc_disallow_IPI_ops_sn2();
2451                 kfree(xpc_remote_copy_buffer_base_sn2);
2452         }
2453         return ret;
2454 }
2455
2456 void
2457 xpc_exit_sn2(void)
2458 {
2459         free_irq(SGI_XPC_ACTIVATE, NULL);
2460         xpc_disallow_IPI_ops_sn2();
2461         kfree(xpc_remote_copy_buffer_base_sn2);
2462 }