Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
[wrt350n-kernel.git] / arch / ia64 / sn / kernel / xpc_partition.c
blob7ba403232cb8321516bbbceb0cb8eeb841a467d8
1 /*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
6 * Copyright (c) 2004-2006 Silicon Graphics, Inc. All Rights Reserved.
7 */
11 * Cross Partition Communication (XPC) partition support.
13 * This is the part of XPC that detects the presence/absence of
14 * other partitions. It provides a heartbeat and monitors the
15 * heartbeats of other partitions.
20 #include <linux/kernel.h>
21 #include <linux/sysctl.h>
22 #include <linux/cache.h>
23 #include <linux/mmzone.h>
24 #include <linux/nodemask.h>
25 #include <asm/uncached.h>
26 #include <asm/sn/bte.h>
27 #include <asm/sn/intr.h>
28 #include <asm/sn/sn_sal.h>
29 #include <asm/sn/nodepda.h>
30 #include <asm/sn/addrs.h>
31 #include <asm/sn/xpc.h>
34 /* XPC is exiting flag */
35 int xpc_exiting;
38 /* SH_IPI_ACCESS shub register value on startup */
39 static u64 xpc_sh1_IPI_access;
40 static u64 xpc_sh2_IPI_access0;
41 static u64 xpc_sh2_IPI_access1;
42 static u64 xpc_sh2_IPI_access2;
43 static u64 xpc_sh2_IPI_access3;
46 /* original protection values for each node */
47 u64 xpc_prot_vec[MAX_NUMNODES];
50 /* this partition's reserved page pointers */
51 struct xpc_rsvd_page *xpc_rsvd_page;
52 static u64 *xpc_part_nasids;
53 static u64 *xpc_mach_nasids;
54 struct xpc_vars *xpc_vars;
55 struct xpc_vars_part *xpc_vars_part;
57 static int xp_nasid_mask_bytes; /* actual size in bytes of nasid mask */
58 static int xp_nasid_mask_words; /* actual size in words of nasid mask */
62 * For performance reasons, each entry of xpc_partitions[] is cacheline
63 * aligned. And xpc_partitions[] is padded with an additional entry at the
64 * end so that the last legitimate entry doesn't share its cacheline with
65 * another variable.
67 struct xpc_partition xpc_partitions[XP_MAX_PARTITIONS + 1];
71 * Generic buffer used to store a local copy of portions of a remote
72 * partition's reserved page (either its header and part_nasids mask,
73 * or its vars).
75 char *xpc_remote_copy_buffer;
76 void *xpc_remote_copy_buffer_base;
80 * Guarantee that the kmalloc'd memory is cacheline aligned.
82 void *
83 xpc_kmalloc_cacheline_aligned(size_t size, gfp_t flags, void **base)
85 /* see if kmalloc will give us cachline aligned memory by default */
86 *base = kmalloc(size, flags);
87 if (*base == NULL) {
88 return NULL;
90 if ((u64) *base == L1_CACHE_ALIGN((u64) *base)) {
91 return *base;
93 kfree(*base);
95 /* nope, we'll have to do it ourselves */
96 *base = kmalloc(size + L1_CACHE_BYTES, flags);
97 if (*base == NULL) {
98 return NULL;
100 return (void *) L1_CACHE_ALIGN((u64) *base);
105 * Given a nasid, get the physical address of the partition's reserved page
106 * for that nasid. This function returns 0 on any error.
108 static u64
109 xpc_get_rsvd_page_pa(int nasid)
111 bte_result_t bte_res;
112 s64 status;
113 u64 cookie = 0;
114 u64 rp_pa = nasid; /* seed with nasid */
115 u64 len = 0;
116 u64 buf = buf;
117 u64 buf_len = 0;
118 void *buf_base = NULL;
121 while (1) {
123 status = sn_partition_reserved_page_pa(buf, &cookie, &rp_pa,
124 &len);
126 dev_dbg(xpc_part, "SAL returned with status=%li, cookie="
127 "0x%016lx, address=0x%016lx, len=0x%016lx\n",
128 status, cookie, rp_pa, len);
130 if (status != SALRET_MORE_PASSES) {
131 break;
134 if (L1_CACHE_ALIGN(len) > buf_len) {
135 kfree(buf_base);
136 buf_len = L1_CACHE_ALIGN(len);
137 buf = (u64) xpc_kmalloc_cacheline_aligned(buf_len,
138 GFP_KERNEL, &buf_base);
139 if (buf_base == NULL) {
140 dev_err(xpc_part, "unable to kmalloc "
141 "len=0x%016lx\n", buf_len);
142 status = SALRET_ERROR;
143 break;
147 bte_res = xp_bte_copy(rp_pa, buf, buf_len,
148 (BTE_NOTIFY | BTE_WACQUIRE), NULL);
149 if (bte_res != BTE_SUCCESS) {
150 dev_dbg(xpc_part, "xp_bte_copy failed %i\n", bte_res);
151 status = SALRET_ERROR;
152 break;
156 kfree(buf_base);
158 if (status != SALRET_OK) {
159 rp_pa = 0;
161 dev_dbg(xpc_part, "reserved page at phys address 0x%016lx\n", rp_pa);
162 return rp_pa;
167 * Fill the partition reserved page with the information needed by
168 * other partitions to discover we are alive and establish initial
169 * communications.
171 struct xpc_rsvd_page *
172 xpc_rsvd_page_init(void)
174 struct xpc_rsvd_page *rp;
175 AMO_t *amos_page;
176 u64 rp_pa, nasid_array = 0;
177 int i, ret;
180 /* get the local reserved page's address */
182 preempt_disable();
183 rp_pa = xpc_get_rsvd_page_pa(cpuid_to_nasid(smp_processor_id()));
184 preempt_enable();
185 if (rp_pa == 0) {
186 dev_err(xpc_part, "SAL failed to locate the reserved page\n");
187 return NULL;
189 rp = (struct xpc_rsvd_page *) __va(rp_pa);
191 if (rp->partid != sn_partition_id) {
192 dev_err(xpc_part, "the reserved page's partid of %d should be "
193 "%d\n", rp->partid, sn_partition_id);
194 return NULL;
197 rp->version = XPC_RP_VERSION;
199 /* establish the actual sizes of the nasid masks */
200 if (rp->SAL_version == 1) {
201 /* SAL_version 1 didn't set the nasids_size field */
202 rp->nasids_size = 128;
204 xp_nasid_mask_bytes = rp->nasids_size;
205 xp_nasid_mask_words = xp_nasid_mask_bytes / 8;
207 /* setup the pointers to the various items in the reserved page */
208 xpc_part_nasids = XPC_RP_PART_NASIDS(rp);
209 xpc_mach_nasids = XPC_RP_MACH_NASIDS(rp);
210 xpc_vars = XPC_RP_VARS(rp);
211 xpc_vars_part = XPC_RP_VARS_PART(rp);
214 * Before clearing xpc_vars, see if a page of AMOs had been previously
215 * allocated. If not we'll need to allocate one and set permissions
216 * so that cross-partition AMOs are allowed.
218 * The allocated AMO page needs MCA reporting to remain disabled after
219 * XPC has unloaded. To make this work, we keep a copy of the pointer
220 * to this page (i.e., amos_page) in the struct xpc_vars structure,
221 * which is pointed to by the reserved page, and re-use that saved copy
222 * on subsequent loads of XPC. This AMO page is never freed, and its
223 * memory protections are never restricted.
225 if ((amos_page = xpc_vars->amos_page) == NULL) {
226 amos_page = (AMO_t *) TO_AMO(uncached_alloc_page(0));
227 if (amos_page == NULL) {
228 dev_err(xpc_part, "can't allocate page of AMOs\n");
229 return NULL;
233 * Open up AMO-R/W to cpu. This is done for Shub 1.1 systems
234 * when xpc_allow_IPI_ops() is called via xpc_hb_init().
236 if (!enable_shub_wars_1_1()) {
237 ret = sn_change_memprotect(ia64_tpa((u64) amos_page),
238 PAGE_SIZE, SN_MEMPROT_ACCESS_CLASS_1,
239 &nasid_array);
240 if (ret != 0) {
241 dev_err(xpc_part, "can't change memory "
242 "protections\n");
243 uncached_free_page(__IA64_UNCACHED_OFFSET |
244 TO_PHYS((u64) amos_page));
245 return NULL;
248 } else if (!IS_AMO_ADDRESS((u64) amos_page)) {
250 * EFI's XPBOOT can also set amos_page in the reserved page,
251 * but it happens to leave it as an uncached physical address
252 * and we need it to be an uncached virtual, so we'll have to
253 * convert it.
255 if (!IS_AMO_PHYS_ADDRESS((u64) amos_page)) {
256 dev_err(xpc_part, "previously used amos_page address "
257 "is bad = 0x%p\n", (void *) amos_page);
258 return NULL;
260 amos_page = (AMO_t *) TO_AMO((u64) amos_page);
263 /* clear xpc_vars */
264 memset(xpc_vars, 0, sizeof(struct xpc_vars));
266 xpc_vars->version = XPC_V_VERSION;
267 xpc_vars->act_nasid = cpuid_to_nasid(0);
268 xpc_vars->act_phys_cpuid = cpu_physical_id(0);
269 xpc_vars->vars_part_pa = __pa(xpc_vars_part);
270 xpc_vars->amos_page_pa = ia64_tpa((u64) amos_page);
271 xpc_vars->amos_page = amos_page; /* save for next load of XPC */
274 /* clear xpc_vars_part */
275 memset((u64 *) xpc_vars_part, 0, sizeof(struct xpc_vars_part) *
276 XP_MAX_PARTITIONS);
278 /* initialize the activate IRQ related AMO variables */
279 for (i = 0; i < xp_nasid_mask_words; i++) {
280 (void) xpc_IPI_init(XPC_ACTIVATE_IRQ_AMOS + i);
283 /* initialize the engaged remote partitions related AMO variables */
284 (void) xpc_IPI_init(XPC_ENGAGED_PARTITIONS_AMO);
285 (void) xpc_IPI_init(XPC_DISENGAGE_REQUEST_AMO);
287 /* timestamp of when reserved page was setup by XPC */
288 rp->stamp = CURRENT_TIME;
291 * This signifies to the remote partition that our reserved
292 * page is initialized.
294 rp->vars_pa = __pa(xpc_vars);
296 return rp;
301 * Change protections to allow IPI operations (and AMO operations on
302 * Shub 1.1 systems).
304 void
305 xpc_allow_IPI_ops(void)
307 int node;
308 int nasid;
311 // >>> Change SH_IPI_ACCESS code to use SAL call once it is available.
313 if (is_shub2()) {
314 xpc_sh2_IPI_access0 =
315 (u64) HUB_L((u64 *) LOCAL_MMR_ADDR(SH2_IPI_ACCESS0));
316 xpc_sh2_IPI_access1 =
317 (u64) HUB_L((u64 *) LOCAL_MMR_ADDR(SH2_IPI_ACCESS1));
318 xpc_sh2_IPI_access2 =
319 (u64) HUB_L((u64 *) LOCAL_MMR_ADDR(SH2_IPI_ACCESS2));
320 xpc_sh2_IPI_access3 =
321 (u64) HUB_L((u64 *) LOCAL_MMR_ADDR(SH2_IPI_ACCESS3));
323 for_each_online_node(node) {
324 nasid = cnodeid_to_nasid(node);
325 HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS0),
326 -1UL);
327 HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS1),
328 -1UL);
329 HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS2),
330 -1UL);
331 HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS3),
332 -1UL);
335 } else {
336 xpc_sh1_IPI_access =
337 (u64) HUB_L((u64 *) LOCAL_MMR_ADDR(SH1_IPI_ACCESS));
339 for_each_online_node(node) {
340 nasid = cnodeid_to_nasid(node);
341 HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, SH1_IPI_ACCESS),
342 -1UL);
345 * Since the BIST collides with memory operations on
346 * SHUB 1.1 sn_change_memprotect() cannot be used.
348 if (enable_shub_wars_1_1()) {
349 /* open up everything */
350 xpc_prot_vec[node] = (u64) HUB_L((u64 *)
351 GLOBAL_MMR_ADDR(nasid,
352 SH1_MD_DQLP_MMR_DIR_PRIVEC0));
353 HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid,
354 SH1_MD_DQLP_MMR_DIR_PRIVEC0),
355 -1UL);
356 HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid,
357 SH1_MD_DQRP_MMR_DIR_PRIVEC0),
358 -1UL);
366 * Restrict protections to disallow IPI operations (and AMO operations on
367 * Shub 1.1 systems).
369 void
370 xpc_restrict_IPI_ops(void)
372 int node;
373 int nasid;
376 // >>> Change SH_IPI_ACCESS code to use SAL call once it is available.
378 if (is_shub2()) {
380 for_each_online_node(node) {
381 nasid = cnodeid_to_nasid(node);
382 HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS0),
383 xpc_sh2_IPI_access0);
384 HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS1),
385 xpc_sh2_IPI_access1);
386 HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS2),
387 xpc_sh2_IPI_access2);
388 HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS3),
389 xpc_sh2_IPI_access3);
392 } else {
394 for_each_online_node(node) {
395 nasid = cnodeid_to_nasid(node);
396 HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, SH1_IPI_ACCESS),
397 xpc_sh1_IPI_access);
399 if (enable_shub_wars_1_1()) {
400 HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid,
401 SH1_MD_DQLP_MMR_DIR_PRIVEC0),
402 xpc_prot_vec[node]);
403 HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid,
404 SH1_MD_DQRP_MMR_DIR_PRIVEC0),
405 xpc_prot_vec[node]);
413 * At periodic intervals, scan through all active partitions and ensure
414 * their heartbeat is still active. If not, the partition is deactivated.
416 void
417 xpc_check_remote_hb(void)
419 struct xpc_vars *remote_vars;
420 struct xpc_partition *part;
421 partid_t partid;
422 bte_result_t bres;
425 remote_vars = (struct xpc_vars *) xpc_remote_copy_buffer;
427 for (partid = 1; partid < XP_MAX_PARTITIONS; partid++) {
429 if (xpc_exiting) {
430 break;
433 if (partid == sn_partition_id) {
434 continue;
437 part = &xpc_partitions[partid];
439 if (part->act_state == XPC_P_INACTIVE ||
440 part->act_state == XPC_P_DEACTIVATING) {
441 continue;
444 /* pull the remote_hb cache line */
445 bres = xp_bte_copy(part->remote_vars_pa,
446 (u64) remote_vars,
447 XPC_RP_VARS_SIZE,
448 (BTE_NOTIFY | BTE_WACQUIRE), NULL);
449 if (bres != BTE_SUCCESS) {
450 XPC_DEACTIVATE_PARTITION(part,
451 xpc_map_bte_errors(bres));
452 continue;
455 dev_dbg(xpc_part, "partid = %d, heartbeat = %ld, last_heartbeat"
456 " = %ld, heartbeat_offline = %ld, HB_mask = 0x%lx\n",
457 partid, remote_vars->heartbeat, part->last_heartbeat,
458 remote_vars->heartbeat_offline,
459 remote_vars->heartbeating_to_mask);
461 if (((remote_vars->heartbeat == part->last_heartbeat) &&
462 (remote_vars->heartbeat_offline == 0)) ||
463 !xpc_hb_allowed(sn_partition_id, remote_vars)) {
465 XPC_DEACTIVATE_PARTITION(part, xpcNoHeartbeat);
466 continue;
469 part->last_heartbeat = remote_vars->heartbeat;
475 * Get a copy of a portion of the remote partition's rsvd page.
477 * remote_rp points to a buffer that is cacheline aligned for BTE copies and
478 * is large enough to contain a copy of their reserved page header and
479 * part_nasids mask.
481 static enum xpc_retval
482 xpc_get_remote_rp(int nasid, u64 *discovered_nasids,
483 struct xpc_rsvd_page *remote_rp, u64 *remote_rp_pa)
485 int bres, i;
488 /* get the reserved page's physical address */
490 *remote_rp_pa = xpc_get_rsvd_page_pa(nasid);
491 if (*remote_rp_pa == 0) {
492 return xpcNoRsvdPageAddr;
496 /* pull over the reserved page header and part_nasids mask */
497 bres = xp_bte_copy(*remote_rp_pa, (u64) remote_rp,
498 XPC_RP_HEADER_SIZE + xp_nasid_mask_bytes,
499 (BTE_NOTIFY | BTE_WACQUIRE), NULL);
500 if (bres != BTE_SUCCESS) {
501 return xpc_map_bte_errors(bres);
505 if (discovered_nasids != NULL) {
506 u64 *remote_part_nasids = XPC_RP_PART_NASIDS(remote_rp);
509 for (i = 0; i < xp_nasid_mask_words; i++) {
510 discovered_nasids[i] |= remote_part_nasids[i];
515 /* check that the partid is for another partition */
517 if (remote_rp->partid < 1 ||
518 remote_rp->partid > (XP_MAX_PARTITIONS - 1)) {
519 return xpcInvalidPartid;
522 if (remote_rp->partid == sn_partition_id) {
523 return xpcLocalPartid;
527 if (XPC_VERSION_MAJOR(remote_rp->version) !=
528 XPC_VERSION_MAJOR(XPC_RP_VERSION)) {
529 return xpcBadVersion;
532 return xpcSuccess;
537 * Get a copy of the remote partition's XPC variables from the reserved page.
539 * remote_vars points to a buffer that is cacheline aligned for BTE copies and
540 * assumed to be of size XPC_RP_VARS_SIZE.
542 static enum xpc_retval
543 xpc_get_remote_vars(u64 remote_vars_pa, struct xpc_vars *remote_vars)
545 int bres;
548 if (remote_vars_pa == 0) {
549 return xpcVarsNotSet;
552 /* pull over the cross partition variables */
553 bres = xp_bte_copy(remote_vars_pa, (u64) remote_vars, XPC_RP_VARS_SIZE,
554 (BTE_NOTIFY | BTE_WACQUIRE), NULL);
555 if (bres != BTE_SUCCESS) {
556 return xpc_map_bte_errors(bres);
559 if (XPC_VERSION_MAJOR(remote_vars->version) !=
560 XPC_VERSION_MAJOR(XPC_V_VERSION)) {
561 return xpcBadVersion;
564 return xpcSuccess;
569 * Update the remote partition's info.
571 static void
572 xpc_update_partition_info(struct xpc_partition *part, u8 remote_rp_version,
573 struct timespec *remote_rp_stamp, u64 remote_rp_pa,
574 u64 remote_vars_pa, struct xpc_vars *remote_vars)
576 part->remote_rp_version = remote_rp_version;
577 dev_dbg(xpc_part, " remote_rp_version = 0x%016x\n",
578 part->remote_rp_version);
580 part->remote_rp_stamp = *remote_rp_stamp;
581 dev_dbg(xpc_part, " remote_rp_stamp (tv_sec = 0x%lx tv_nsec = 0x%lx\n",
582 part->remote_rp_stamp.tv_sec, part->remote_rp_stamp.tv_nsec);
584 part->remote_rp_pa = remote_rp_pa;
585 dev_dbg(xpc_part, " remote_rp_pa = 0x%016lx\n", part->remote_rp_pa);
587 part->remote_vars_pa = remote_vars_pa;
588 dev_dbg(xpc_part, " remote_vars_pa = 0x%016lx\n",
589 part->remote_vars_pa);
591 part->last_heartbeat = remote_vars->heartbeat;
592 dev_dbg(xpc_part, " last_heartbeat = 0x%016lx\n",
593 part->last_heartbeat);
595 part->remote_vars_part_pa = remote_vars->vars_part_pa;
596 dev_dbg(xpc_part, " remote_vars_part_pa = 0x%016lx\n",
597 part->remote_vars_part_pa);
599 part->remote_act_nasid = remote_vars->act_nasid;
600 dev_dbg(xpc_part, " remote_act_nasid = 0x%x\n",
601 part->remote_act_nasid);
603 part->remote_act_phys_cpuid = remote_vars->act_phys_cpuid;
604 dev_dbg(xpc_part, " remote_act_phys_cpuid = 0x%x\n",
605 part->remote_act_phys_cpuid);
607 part->remote_amos_page_pa = remote_vars->amos_page_pa;
608 dev_dbg(xpc_part, " remote_amos_page_pa = 0x%lx\n",
609 part->remote_amos_page_pa);
611 part->remote_vars_version = remote_vars->version;
612 dev_dbg(xpc_part, " remote_vars_version = 0x%x\n",
613 part->remote_vars_version);
618 * Prior code has determined the nasid which generated an IPI. Inspect
619 * that nasid to determine if its partition needs to be activated or
620 * deactivated.
622 * A partition is consider "awaiting activation" if our partition
623 * flags indicate it is not active and it has a heartbeat. A
624 * partition is considered "awaiting deactivation" if our partition
625 * flags indicate it is active but it has no heartbeat or it is not
626 * sending its heartbeat to us.
628 * To determine the heartbeat, the remote nasid must have a properly
629 * initialized reserved page.
631 static void
632 xpc_identify_act_IRQ_req(int nasid)
634 struct xpc_rsvd_page *remote_rp;
635 struct xpc_vars *remote_vars;
636 u64 remote_rp_pa;
637 u64 remote_vars_pa;
638 int remote_rp_version;
639 int reactivate = 0;
640 int stamp_diff;
641 struct timespec remote_rp_stamp = { 0, 0 };
642 partid_t partid;
643 struct xpc_partition *part;
644 enum xpc_retval ret;
647 /* pull over the reserved page structure */
649 remote_rp = (struct xpc_rsvd_page *) xpc_remote_copy_buffer;
651 ret = xpc_get_remote_rp(nasid, NULL, remote_rp, &remote_rp_pa);
652 if (ret != xpcSuccess) {
653 dev_warn(xpc_part, "unable to get reserved page from nasid %d, "
654 "which sent interrupt, reason=%d\n", nasid, ret);
655 return;
658 remote_vars_pa = remote_rp->vars_pa;
659 remote_rp_version = remote_rp->version;
660 if (XPC_SUPPORTS_RP_STAMP(remote_rp_version)) {
661 remote_rp_stamp = remote_rp->stamp;
663 partid = remote_rp->partid;
664 part = &xpc_partitions[partid];
667 /* pull over the cross partition variables */
669 remote_vars = (struct xpc_vars *) xpc_remote_copy_buffer;
671 ret = xpc_get_remote_vars(remote_vars_pa, remote_vars);
672 if (ret != xpcSuccess) {
674 dev_warn(xpc_part, "unable to get XPC variables from nasid %d, "
675 "which sent interrupt, reason=%d\n", nasid, ret);
677 XPC_DEACTIVATE_PARTITION(part, ret);
678 return;
682 part->act_IRQ_rcvd++;
684 dev_dbg(xpc_part, "partid for nasid %d is %d; IRQs = %d; HB = "
685 "%ld:0x%lx\n", (int) nasid, (int) partid, part->act_IRQ_rcvd,
686 remote_vars->heartbeat, remote_vars->heartbeating_to_mask);
688 if (xpc_partition_disengaged(part) &&
689 part->act_state == XPC_P_INACTIVE) {
691 xpc_update_partition_info(part, remote_rp_version,
692 &remote_rp_stamp, remote_rp_pa,
693 remote_vars_pa, remote_vars);
695 if (XPC_SUPPORTS_DISENGAGE_REQUEST(part->remote_vars_version)) {
696 if (xpc_partition_disengage_requested(1UL << partid)) {
698 * Other side is waiting on us to disengage,
699 * even though we already have.
701 return;
703 } else {
704 /* other side doesn't support disengage requests */
705 xpc_clear_partition_disengage_request(1UL << partid);
708 xpc_activate_partition(part);
709 return;
712 DBUG_ON(part->remote_rp_version == 0);
713 DBUG_ON(part->remote_vars_version == 0);
715 if (!XPC_SUPPORTS_RP_STAMP(part->remote_rp_version)) {
716 DBUG_ON(XPC_SUPPORTS_DISENGAGE_REQUEST(part->
717 remote_vars_version));
719 if (!XPC_SUPPORTS_RP_STAMP(remote_rp_version)) {
720 DBUG_ON(XPC_SUPPORTS_DISENGAGE_REQUEST(remote_vars->
721 version));
722 /* see if the other side rebooted */
723 if (part->remote_amos_page_pa ==
724 remote_vars->amos_page_pa &&
725 xpc_hb_allowed(sn_partition_id,
726 remote_vars)) {
727 /* doesn't look that way, so ignore the IPI */
728 return;
733 * Other side rebooted and previous XPC didn't support the
734 * disengage request, so we don't need to do anything special.
737 xpc_update_partition_info(part, remote_rp_version,
738 &remote_rp_stamp, remote_rp_pa,
739 remote_vars_pa, remote_vars);
740 part->reactivate_nasid = nasid;
741 XPC_DEACTIVATE_PARTITION(part, xpcReactivating);
742 return;
745 DBUG_ON(!XPC_SUPPORTS_DISENGAGE_REQUEST(part->remote_vars_version));
747 if (!XPC_SUPPORTS_RP_STAMP(remote_rp_version)) {
748 DBUG_ON(!XPC_SUPPORTS_DISENGAGE_REQUEST(remote_vars->version));
751 * Other side rebooted and previous XPC did support the
752 * disengage request, but the new one doesn't.
755 xpc_clear_partition_engaged(1UL << partid);
756 xpc_clear_partition_disengage_request(1UL << partid);
758 xpc_update_partition_info(part, remote_rp_version,
759 &remote_rp_stamp, remote_rp_pa,
760 remote_vars_pa, remote_vars);
761 reactivate = 1;
763 } else {
764 DBUG_ON(!XPC_SUPPORTS_DISENGAGE_REQUEST(remote_vars->version));
766 stamp_diff = xpc_compare_stamps(&part->remote_rp_stamp,
767 &remote_rp_stamp);
768 if (stamp_diff != 0) {
769 DBUG_ON(stamp_diff >= 0);
772 * Other side rebooted and the previous XPC did support
773 * the disengage request, as does the new one.
776 DBUG_ON(xpc_partition_engaged(1UL << partid));
777 DBUG_ON(xpc_partition_disengage_requested(1UL <<
778 partid));
780 xpc_update_partition_info(part, remote_rp_version,
781 &remote_rp_stamp, remote_rp_pa,
782 remote_vars_pa, remote_vars);
783 reactivate = 1;
787 if (part->disengage_request_timeout > 0 &&
788 !xpc_partition_disengaged(part)) {
789 /* still waiting on other side to disengage from us */
790 return;
793 if (reactivate) {
794 part->reactivate_nasid = nasid;
795 XPC_DEACTIVATE_PARTITION(part, xpcReactivating);
797 } else if (XPC_SUPPORTS_DISENGAGE_REQUEST(part->remote_vars_version) &&
798 xpc_partition_disengage_requested(1UL << partid)) {
799 XPC_DEACTIVATE_PARTITION(part, xpcOtherGoingDown);
805 * Loop through the activation AMO variables and process any bits
806 * which are set. Each bit indicates a nasid sending a partition
807 * activation or deactivation request.
809 * Return #of IRQs detected.
812 xpc_identify_act_IRQ_sender(void)
814 int word, bit;
815 u64 nasid_mask;
816 u64 nasid; /* remote nasid */
817 int n_IRQs_detected = 0;
818 AMO_t *act_amos;
821 act_amos = xpc_vars->amos_page + XPC_ACTIVATE_IRQ_AMOS;
824 /* scan through act AMO variable looking for non-zero entries */
825 for (word = 0; word < xp_nasid_mask_words; word++) {
827 if (xpc_exiting) {
828 break;
831 nasid_mask = xpc_IPI_receive(&act_amos[word]);
832 if (nasid_mask == 0) {
833 /* no IRQs from nasids in this variable */
834 continue;
837 dev_dbg(xpc_part, "AMO[%d] gave back 0x%lx\n", word,
838 nasid_mask);
842 * If this nasid has been added to the machine since
843 * our partition was reset, this will retain the
844 * remote nasid in our reserved pages machine mask.
845 * This is used in the event of module reload.
847 xpc_mach_nasids[word] |= nasid_mask;
850 /* locate the nasid(s) which sent interrupts */
852 for (bit = 0; bit < (8 * sizeof(u64)); bit++) {
853 if (nasid_mask & (1UL << bit)) {
854 n_IRQs_detected++;
855 nasid = XPC_NASID_FROM_W_B(word, bit);
856 dev_dbg(xpc_part, "interrupt from nasid %ld\n",
857 nasid);
858 xpc_identify_act_IRQ_req(nasid);
862 return n_IRQs_detected;
867 * See if the other side has responded to a partition disengage request
868 * from us.
871 xpc_partition_disengaged(struct xpc_partition *part)
873 partid_t partid = XPC_PARTID(part);
874 int disengaged;
877 disengaged = (xpc_partition_engaged(1UL << partid) == 0);
878 if (part->disengage_request_timeout) {
879 if (!disengaged) {
880 if (jiffies < part->disengage_request_timeout) {
881 /* timelimit hasn't been reached yet */
882 return 0;
886 * Other side hasn't responded to our disengage
887 * request in a timely fashion, so assume it's dead.
890 dev_info(xpc_part, "disengage from remote partition %d "
891 "timed out\n", partid);
892 xpc_disengage_request_timedout = 1;
893 xpc_clear_partition_engaged(1UL << partid);
894 disengaged = 1;
896 part->disengage_request_timeout = 0;
898 /* cancel the timer function, provided it's not us */
899 if (!in_interrupt()) {
900 del_singleshot_timer_sync(&part->
901 disengage_request_timer);
904 DBUG_ON(part->act_state != XPC_P_DEACTIVATING &&
905 part->act_state != XPC_P_INACTIVE);
906 if (part->act_state != XPC_P_INACTIVE) {
907 xpc_wakeup_channel_mgr(part);
910 if (XPC_SUPPORTS_DISENGAGE_REQUEST(part->remote_vars_version)) {
911 xpc_cancel_partition_disengage_request(part);
914 return disengaged;
919 * Mark specified partition as active.
921 enum xpc_retval
922 xpc_mark_partition_active(struct xpc_partition *part)
924 unsigned long irq_flags;
925 enum xpc_retval ret;
928 dev_dbg(xpc_part, "setting partition %d to ACTIVE\n", XPC_PARTID(part));
930 spin_lock_irqsave(&part->act_lock, irq_flags);
931 if (part->act_state == XPC_P_ACTIVATING) {
932 part->act_state = XPC_P_ACTIVE;
933 ret = xpcSuccess;
934 } else {
935 DBUG_ON(part->reason == xpcSuccess);
936 ret = part->reason;
938 spin_unlock_irqrestore(&part->act_lock, irq_flags);
940 return ret;
945 * Notify XPC that the partition is down.
947 void
948 xpc_deactivate_partition(const int line, struct xpc_partition *part,
949 enum xpc_retval reason)
951 unsigned long irq_flags;
954 spin_lock_irqsave(&part->act_lock, irq_flags);
956 if (part->act_state == XPC_P_INACTIVE) {
957 XPC_SET_REASON(part, reason, line);
958 spin_unlock_irqrestore(&part->act_lock, irq_flags);
959 if (reason == xpcReactivating) {
960 /* we interrupt ourselves to reactivate partition */
961 xpc_IPI_send_reactivate(part);
963 return;
965 if (part->act_state == XPC_P_DEACTIVATING) {
966 if ((part->reason == xpcUnloading && reason != xpcUnloading) ||
967 reason == xpcReactivating) {
968 XPC_SET_REASON(part, reason, line);
970 spin_unlock_irqrestore(&part->act_lock, irq_flags);
971 return;
974 part->act_state = XPC_P_DEACTIVATING;
975 XPC_SET_REASON(part, reason, line);
977 spin_unlock_irqrestore(&part->act_lock, irq_flags);
979 if (XPC_SUPPORTS_DISENGAGE_REQUEST(part->remote_vars_version)) {
980 xpc_request_partition_disengage(part);
981 xpc_IPI_send_disengage(part);
983 /* set a timelimit on the disengage request */
984 part->disengage_request_timeout = jiffies +
985 (xpc_disengage_request_timelimit * HZ);
986 part->disengage_request_timer.expires =
987 part->disengage_request_timeout;
988 add_timer(&part->disengage_request_timer);
991 dev_dbg(xpc_part, "bringing partition %d down, reason = %d\n",
992 XPC_PARTID(part), reason);
994 xpc_partition_going_down(part, reason);
999 * Mark specified partition as inactive.
1001 void
1002 xpc_mark_partition_inactive(struct xpc_partition *part)
1004 unsigned long irq_flags;
1007 dev_dbg(xpc_part, "setting partition %d to INACTIVE\n",
1008 XPC_PARTID(part));
1010 spin_lock_irqsave(&part->act_lock, irq_flags);
1011 part->act_state = XPC_P_INACTIVE;
1012 spin_unlock_irqrestore(&part->act_lock, irq_flags);
1013 part->remote_rp_pa = 0;
1018 * SAL has provided a partition and machine mask. The partition mask
1019 * contains a bit for each even nasid in our partition. The machine
1020 * mask contains a bit for each even nasid in the entire machine.
1022 * Using those two bit arrays, we can determine which nasids are
1023 * known in the machine. Each should also have a reserved page
1024 * initialized if they are available for partitioning.
1026 void
1027 xpc_discovery(void)
1029 void *remote_rp_base;
1030 struct xpc_rsvd_page *remote_rp;
1031 struct xpc_vars *remote_vars;
1032 u64 remote_rp_pa;
1033 u64 remote_vars_pa;
1034 int region;
1035 int region_size;
1036 int max_regions;
1037 int nasid;
1038 struct xpc_rsvd_page *rp;
1039 partid_t partid;
1040 struct xpc_partition *part;
1041 u64 *discovered_nasids;
1042 enum xpc_retval ret;
1045 remote_rp = xpc_kmalloc_cacheline_aligned(XPC_RP_HEADER_SIZE +
1046 xp_nasid_mask_bytes,
1047 GFP_KERNEL, &remote_rp_base);
1048 if (remote_rp == NULL) {
1049 return;
1051 remote_vars = (struct xpc_vars *) remote_rp;
1054 discovered_nasids = kzalloc(sizeof(u64) * xp_nasid_mask_words,
1055 GFP_KERNEL);
1056 if (discovered_nasids == NULL) {
1057 kfree(remote_rp_base);
1058 return;
1061 rp = (struct xpc_rsvd_page *) xpc_rsvd_page;
1064 * The term 'region' in this context refers to the minimum number of
1065 * nodes that can comprise an access protection grouping. The access
1066 * protection is in regards to memory, IOI and IPI.
1068 max_regions = 64;
1069 region_size = sn_region_size;
1071 switch (region_size) {
1072 case 128:
1073 max_regions *= 2;
1074 case 64:
1075 max_regions *= 2;
1076 case 32:
1077 max_regions *= 2;
1078 region_size = 16;
1079 DBUG_ON(!is_shub2());
1082 for (region = 0; region < max_regions; region++) {
1084 if ((volatile int) xpc_exiting) {
1085 break;
1088 dev_dbg(xpc_part, "searching region %d\n", region);
1090 for (nasid = (region * region_size * 2);
1091 nasid < ((region + 1) * region_size * 2);
1092 nasid += 2) {
1094 if ((volatile int) xpc_exiting) {
1095 break;
1098 dev_dbg(xpc_part, "checking nasid %d\n", nasid);
1101 if (XPC_NASID_IN_ARRAY(nasid, xpc_part_nasids)) {
1102 dev_dbg(xpc_part, "PROM indicates Nasid %d is "
1103 "part of the local partition; skipping "
1104 "region\n", nasid);
1105 break;
1108 if (!(XPC_NASID_IN_ARRAY(nasid, xpc_mach_nasids))) {
1109 dev_dbg(xpc_part, "PROM indicates Nasid %d was "
1110 "not on Numa-Link network at reset\n",
1111 nasid);
1112 continue;
1115 if (XPC_NASID_IN_ARRAY(nasid, discovered_nasids)) {
1116 dev_dbg(xpc_part, "Nasid %d is part of a "
1117 "partition which was previously "
1118 "discovered\n", nasid);
1119 continue;
1123 /* pull over the reserved page structure */
1125 ret = xpc_get_remote_rp(nasid, discovered_nasids,
1126 remote_rp, &remote_rp_pa);
1127 if (ret != xpcSuccess) {
1128 dev_dbg(xpc_part, "unable to get reserved page "
1129 "from nasid %d, reason=%d\n", nasid,
1130 ret);
1132 if (ret == xpcLocalPartid) {
1133 break;
1135 continue;
1138 remote_vars_pa = remote_rp->vars_pa;
1140 partid = remote_rp->partid;
1141 part = &xpc_partitions[partid];
1144 /* pull over the cross partition variables */
1146 ret = xpc_get_remote_vars(remote_vars_pa, remote_vars);
1147 if (ret != xpcSuccess) {
1148 dev_dbg(xpc_part, "unable to get XPC variables "
1149 "from nasid %d, reason=%d\n", nasid,
1150 ret);
1152 XPC_DEACTIVATE_PARTITION(part, ret);
1153 continue;
1156 if (part->act_state != XPC_P_INACTIVE) {
1157 dev_dbg(xpc_part, "partition %d on nasid %d is "
1158 "already activating\n", partid, nasid);
1159 break;
1163 * Register the remote partition's AMOs with SAL so it
1164 * can handle and cleanup errors within that address
1165 * range should the remote partition go down. We don't
1166 * unregister this range because it is difficult to
1167 * tell when outstanding writes to the remote partition
1168 * are finished and thus when it is thus safe to
1169 * unregister. This should not result in wasted space
1170 * in the SAL xp_addr_region table because we should
1171 * get the same page for remote_act_amos_pa after
1172 * module reloads and system reboots.
1174 if (sn_register_xp_addr_region(
1175 remote_vars->amos_page_pa,
1176 PAGE_SIZE, 1) < 0) {
1177 dev_dbg(xpc_part, "partition %d failed to "
1178 "register xp_addr region 0x%016lx\n",
1179 partid, remote_vars->amos_page_pa);
1181 XPC_SET_REASON(part, xpcPhysAddrRegFailed,
1182 __LINE__);
1183 break;
1187 * The remote nasid is valid and available.
1188 * Send an interrupt to that nasid to notify
1189 * it that we are ready to begin activation.
1191 dev_dbg(xpc_part, "sending an interrupt to AMO 0x%lx, "
1192 "nasid %d, phys_cpuid 0x%x\n",
1193 remote_vars->amos_page_pa,
1194 remote_vars->act_nasid,
1195 remote_vars->act_phys_cpuid);
1197 if (XPC_SUPPORTS_DISENGAGE_REQUEST(remote_vars->
1198 version)) {
1199 part->remote_amos_page_pa =
1200 remote_vars->amos_page_pa;
1201 xpc_mark_partition_disengaged(part);
1202 xpc_cancel_partition_disengage_request(part);
1204 xpc_IPI_send_activate(remote_vars);
1208 kfree(discovered_nasids);
1209 kfree(remote_rp_base);
1214 * Given a partid, get the nasids owned by that partition from the
1215 * remote partition's reserved page.
1217 enum xpc_retval
1218 xpc_initiate_partid_to_nasids(partid_t partid, void *nasid_mask)
1220 struct xpc_partition *part;
1221 u64 part_nasid_pa;
1222 int bte_res;
1225 part = &xpc_partitions[partid];
1226 if (part->remote_rp_pa == 0) {
1227 return xpcPartitionDown;
1230 memset(nasid_mask, 0, XP_NASID_MASK_BYTES);
1232 part_nasid_pa = (u64) XPC_RP_PART_NASIDS(part->remote_rp_pa);
1234 bte_res = xp_bte_copy(part_nasid_pa, (u64) nasid_mask,
1235 xp_nasid_mask_bytes, (BTE_NOTIFY | BTE_WACQUIRE), NULL);
1237 return xpc_map_bte_errors(bte_res);