arch/ia64/sn/kernel/xpc_partition.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) 2004-2005 Silicon Graphics, Inc.  All Rights Reserved.
   7  */
   8
   9
  10 /*
  11  * Cross Partition Communication (XPC) partition support.
  12  *
  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.
  16  *
  17  */
  18
  19
  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 "xpc.h"
  32
  33
  34 /* XPC is exiting flag */
  35 int xpc_exiting;
  36
  37
  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;
  44
  45
  46 /* original protection values for each node */
  47 u64 xpc_prot_vec[MAX_COMPACT_NODES];
  48
  49
  50 /* this partition's reserved page */
  51 struct xpc_rsvd_page *xpc_rsvd_page;
  52
  53 /* this partition's XPC variables (within the reserved page) */
  54 struct xpc_vars *xpc_vars;
  55 struct xpc_vars_part *xpc_vars_part;
  56
  57
  58 /*
  59  * For performance reasons, each entry of xpc_partitions[] is cacheline
  60  * aligned. And xpc_partitions[] is padded with an additional entry at the
  61  * end so that the last legitimate entry doesn't share its cacheline with
  62  * another variable.
  63  */
  64 struct xpc_partition xpc_partitions[XP_MAX_PARTITIONS + 1];
  65
  66
  67 /*
  68  * Generic buffer used to store a local copy of the remote partitions
  69  * reserved page or XPC variables.
  70  *
  71  * xpc_discovery runs only once and is a seperate thread that is
  72  * very likely going to be processing in parallel with receiving
  73  * interrupts.
  74  */
  75 char ____cacheline_aligned
  76                 xpc_remote_copy_buffer[XPC_RSVD_PAGE_ALIGNED_SIZE];
  77
  78
  79 /* systune related variables */
  80 int xpc_hb_interval = XPC_HB_DEFAULT_INTERVAL;
  81 int xpc_hb_check_interval = XPC_HB_CHECK_DEFAULT_TIMEOUT;
  82
  83
  84 /*
  85  * Given a nasid, get the physical address of the  partition's reserved page
  86  * for that nasid. This function returns 0 on any error.
  87  */
  88 static u64
  89 xpc_get_rsvd_page_pa(int nasid, u64 buf, u64 buf_size)
  90 {
  91         bte_result_t bte_res;
  92         s64 status;
  93         u64 cookie = 0;
  94         u64 rp_pa = nasid;      /* seed with nasid */
  95         u64 len = 0;
  96
  97
  98         while (1) {
  99
 100                 status = sn_partition_reserved_page_pa(buf, &cookie, &rp_pa,
 101                                                                 &len);
 102
 103                 dev_dbg(xpc_part, "SAL returned with status=%li, cookie="
 104                         "0x%016lx, address=0x%016lx, len=0x%016lx\n",
 105                         status, cookie, rp_pa, len);
 106
 107                 if (status != SALRET_MORE_PASSES) {
 108                         break;
 109                 }
 110
 111                 if (len > buf_size) {
 112                         dev_err(xpc_part, "len (=0x%016lx) > buf_size\n", len);
 113                         status = SALRET_ERROR;
 114                         break;
 115                 }
 116
 117                 bte_res = xp_bte_copy(rp_pa, ia64_tpa(buf), buf_size,
 118                                         (BTE_NOTIFY | BTE_WACQUIRE), NULL);
 119                 if (bte_res != BTE_SUCCESS) {
 120                         dev_dbg(xpc_part, "xp_bte_copy failed %i\n", bte_res);
 121                         status = SALRET_ERROR;
 122                         break;
 123                 }
 124         }
 125
 126         if (status != SALRET_OK) {
 127                 rp_pa = 0;
 128         }
 129         dev_dbg(xpc_part, "reserved page at phys address 0x%016lx\n", rp_pa);
 130         return rp_pa;
 131 }
 132
 133
 134 /*
 135  * Fill the partition reserved page with the information needed by
 136  * other partitions to discover we are alive and establish initial
 137  * communications.
 138  */
 139 struct xpc_rsvd_page *
 140 xpc_rsvd_page_init(void)
 141 {
 142         struct xpc_rsvd_page *rp;
 143         AMO_t *amos_page;
 144         u64 rp_pa, next_cl, nasid_array = 0;
 145         int i, ret;
 146
 147
 148         /* get the local reserved page's address */
 149
 150         rp_pa = xpc_get_rsvd_page_pa(cnodeid_to_nasid(0),
 151                                         (u64) xpc_remote_copy_buffer,
 152                                                 XPC_RSVD_PAGE_ALIGNED_SIZE);
 153         if (rp_pa == 0) {
 154                 dev_err(xpc_part, "SAL failed to locate the reserved page\n");
 155                 return NULL;
 156         }
 157         rp = (struct xpc_rsvd_page *) __va(rp_pa);
 158
 159         if (rp->partid != sn_partition_id) {
 160                 dev_err(xpc_part, "the reserved page's partid of %d should be "
 161                         "%d\n", rp->partid, sn_partition_id);
 162                 return NULL;
 163         }
 164
 165         rp->version = XPC_RP_VERSION;
 166
 167         /*
 168          * Place the XPC variables on the cache line following the
 169          * reserved page structure.
 170          */
 171         next_cl = (u64) rp + XPC_RSVD_PAGE_ALIGNED_SIZE;
 172         xpc_vars = (struct xpc_vars *) next_cl;
 173
 174         /*
 175          * Before clearing xpc_vars, see if a page of AMOs had been previously
 176          * allocated. If not we'll need to allocate one and set permissions
 177          * so that cross-partition AMOs are allowed.
 178          *
 179          * The allocated AMO page needs MCA reporting to remain disabled after
 180          * XPC has unloaded.  To make this work, we keep a copy of the pointer
 181          * to this page (i.e., amos_page) in the struct xpc_vars structure,
 182          * which is pointed to by the reserved page, and re-use that saved copy
 183          * on subsequent loads of XPC. This AMO page is never freed, and its
 184          * memory protections are never restricted.
 185          */
 186         if ((amos_page = xpc_vars->amos_page) == NULL) {
 187                 amos_page = (AMO_t *) TO_AMO(uncached_alloc_page(0));
 188                 if (amos_page == NULL) {
 189                         dev_err(xpc_part, "can't allocate page of AMOs\n");
 190                         return NULL;
 191                 }
 192
 193                 /*
 194                  * Open up AMO-R/W to cpu.  This is done for Shub 1.1 systems
 195                  * when xpc_allow_IPI_ops() is called via xpc_hb_init().
 196                  */
 197                 if (!enable_shub_wars_1_1()) {
 198                         ret = sn_change_memprotect(ia64_tpa((u64) amos_page),
 199                                         PAGE_SIZE, SN_MEMPROT_ACCESS_CLASS_1,
 200                                         &nasid_array);
 201                         if (ret != 0) {
 202                                 dev_err(xpc_part, "can't change memory "
 203                                         "protections\n");
 204                                 uncached_free_page(__IA64_UNCACHED_OFFSET |
 205                                                    TO_PHYS((u64) amos_page));
 206                                 return NULL;
 207                         }
 208                 }
 209         } else if (!IS_AMO_ADDRESS((u64) amos_page)) {
 210                 /*
 211                  * EFI's XPBOOT can also set amos_page in the reserved page,
 212                  * but it happens to leave it as an uncached physical address
 213                  * and we need it to be an uncached virtual, so we'll have to
 214                  * convert it.
 215                  */
 216                 if (!IS_AMO_PHYS_ADDRESS((u64) amos_page)) {
 217                         dev_err(xpc_part, "previously used amos_page address "
 218                                 "is bad = 0x%p\n", (void *) amos_page);
 219                         return NULL;
 220                 }
 221                 amos_page = (AMO_t *) TO_AMO((u64) amos_page);
 222         }
 223
 224         memset(xpc_vars, 0, sizeof(struct xpc_vars));
 225
 226         /*
 227          * Place the XPC per partition specific variables on the cache line
 228          * following the XPC variables structure.
 229          */
 230         next_cl += XPC_VARS_ALIGNED_SIZE;
 231         memset((u64 *) next_cl, 0, sizeof(struct xpc_vars_part) *
 232                                                         XP_MAX_PARTITIONS);
 233         xpc_vars_part = (struct xpc_vars_part *) next_cl;
 234         xpc_vars->vars_part_pa = __pa(next_cl);
 235
 236         xpc_vars->version = XPC_V_VERSION;
 237         xpc_vars->act_nasid = cpuid_to_nasid(0);
 238         xpc_vars->act_phys_cpuid = cpu_physical_id(0);
 239         xpc_vars->amos_page = amos_page;  /* save for next load of XPC */
 240
 241
 242         /*
 243          * Initialize the activation related AMO variables.
 244          */
 245         xpc_vars->act_amos = xpc_IPI_init(XP_MAX_PARTITIONS);
 246         for (i = 1; i < XP_NASID_MASK_WORDS; i++) {
 247                 xpc_IPI_init(i + XP_MAX_PARTITIONS);
 248         }
 249         /* export AMO page's physical address to other partitions */
 250         xpc_vars->amos_page_pa = ia64_tpa((u64) xpc_vars->amos_page);
 251
 252         /*
 253          * This signifies to the remote partition that our reserved
 254          * page is initialized.
 255          */
 256         rp->vars_pa = __pa(xpc_vars);
 257
 258         return rp;
 259 }
 260
 261
 262 /*
 263  * Change protections to allow IPI operations (and AMO operations on
 264  * Shub 1.1 systems).
 265  */
 266 void
 267 xpc_allow_IPI_ops(void)
 268 {
 269         int node;
 270         int nasid;
 271
 272
 273         // >>> Change SH_IPI_ACCESS code to use SAL call once it is available.
 274
 275         if (is_shub2()) {
 276                 xpc_sh2_IPI_access0 =
 277                         (u64) HUB_L((u64 *) LOCAL_MMR_ADDR(SH2_IPI_ACCESS0));
 278                 xpc_sh2_IPI_access1 =
 279                         (u64) HUB_L((u64 *) LOCAL_MMR_ADDR(SH2_IPI_ACCESS1));
 280                 xpc_sh2_IPI_access2 =
 281                         (u64) HUB_L((u64 *) LOCAL_MMR_ADDR(SH2_IPI_ACCESS2));
 282                 xpc_sh2_IPI_access3 =
 283                         (u64) HUB_L((u64 *) LOCAL_MMR_ADDR(SH2_IPI_ACCESS3));
 284
 285                 for_each_online_node(node) {
 286                         nasid = cnodeid_to_nasid(node);
 287                         HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS0),
 288                                                                 -1UL);
 289                         HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS1),
 290                                                                 -1UL);
 291                         HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS2),
 292                                                                 -1UL);
 293                         HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS3),
 294                                                                 -1UL);
 295                 }
 296
 297         } else {
 298                 xpc_sh1_IPI_access =
 299                         (u64) HUB_L((u64 *) LOCAL_MMR_ADDR(SH1_IPI_ACCESS));
 300
 301                 for_each_online_node(node) {
 302                         nasid = cnodeid_to_nasid(node);
 303                         HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, SH1_IPI_ACCESS),
 304                                                                 -1UL);
 305
 306                         /*
 307                          * Since the BIST collides with memory operations on
 308                          * SHUB 1.1 sn_change_memprotect() cannot be used.
 309                          */
 310                         if (enable_shub_wars_1_1()) {
 311                                 /* open up everything */
 312                                 xpc_prot_vec[node] = (u64) HUB_L((u64 *)
 313                                                 GLOBAL_MMR_ADDR(nasid,
 314                                                 SH1_MD_DQLP_MMR_DIR_PRIVEC0));
 315                                 HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid,
 316                                                 SH1_MD_DQLP_MMR_DIR_PRIVEC0),
 317                                                                 -1UL);
 318                                 HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid,
 319                                                 SH1_MD_DQRP_MMR_DIR_PRIVEC0),
 320                                                                 -1UL);
 321                         }
 322                 }
 323         }
 324 }
 325
 326
 327 /*
 328  * Restrict protections to disallow IPI operations (and AMO operations on
 329  * Shub 1.1 systems).
 330  */
 331 void
 332 xpc_restrict_IPI_ops(void)
 333 {
 334         int node;
 335         int nasid;
 336
 337
 338         // >>> Change SH_IPI_ACCESS code to use SAL call once it is available.
 339
 340         if (is_shub2()) {
 341
 342                 for_each_online_node(node) {
 343                         nasid = cnodeid_to_nasid(node);
 344                         HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS0),
 345                                                         xpc_sh2_IPI_access0);
 346                         HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS1),
 347                                                         xpc_sh2_IPI_access1);
 348                         HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS2),
 349                                                         xpc_sh2_IPI_access2);
 350                         HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, SH2_IPI_ACCESS3),
 351                                                         xpc_sh2_IPI_access3);
 352                 }
 353
 354         } else {
 355
 356                 for_each_online_node(node) {
 357                         nasid = cnodeid_to_nasid(node);
 358                         HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid, SH1_IPI_ACCESS),
 359                                                         xpc_sh1_IPI_access);
 360
 361                         if (enable_shub_wars_1_1()) {
 362                                 HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid,
 363                                                 SH1_MD_DQLP_MMR_DIR_PRIVEC0),
 364                                                         xpc_prot_vec[node]);
 365                                 HUB_S((u64 *) GLOBAL_MMR_ADDR(nasid,
 366                                                 SH1_MD_DQRP_MMR_DIR_PRIVEC0),
 367                                                         xpc_prot_vec[node]);
 368                         }
 369                 }
 370         }
 371 }
 372
 373
 374 /*
 375  * At periodic intervals, scan through all active partitions and ensure
 376  * their heartbeat is still active.  If not, the partition is deactivated.
 377  */
 378 void
 379 xpc_check_remote_hb(void)
 380 {
 381         struct xpc_vars *remote_vars;
 382         struct xpc_partition *part;
 383         partid_t partid;
 384         bte_result_t bres;
 385
 386
 387         remote_vars = (struct xpc_vars *) xpc_remote_copy_buffer;
 388
 389         for (partid = 1; partid < XP_MAX_PARTITIONS; partid++) {
 390                 if (partid == sn_partition_id) {
 391                         continue;
 392                 }
 393
 394                 part = &xpc_partitions[partid];
 395
 396                 if (part->act_state == XPC_P_INACTIVE ||
 397                                 part->act_state == XPC_P_DEACTIVATING) {
 398                         continue;
 399                 }
 400
 401                 /* pull the remote_hb cache line */
 402                 bres = xp_bte_copy(part->remote_vars_pa,
 403                                         ia64_tpa((u64) remote_vars),
 404                                         XPC_VARS_ALIGNED_SIZE,
 405                                         (BTE_NOTIFY | BTE_WACQUIRE), NULL);
 406                 if (bres != BTE_SUCCESS) {
 407                         XPC_DEACTIVATE_PARTITION(part,
 408                                                 xpc_map_bte_errors(bres));
 409                         continue;
 410                 }
 411
 412                 dev_dbg(xpc_part, "partid = %d, heartbeat = %ld, last_heartbeat"
 413                         " = %ld, kdb_status = %ld, HB_mask = 0x%lx\n", partid,
 414                         remote_vars->heartbeat, part->last_heartbeat,
 415                         remote_vars->kdb_status,
 416                         remote_vars->heartbeating_to_mask);
 417
 418                 if (((remote_vars->heartbeat == part->last_heartbeat) &&
 419                         (remote_vars->kdb_status == 0)) ||
 420                              !XPC_HB_ALLOWED(sn_partition_id, remote_vars)) {
 421
 422                         XPC_DEACTIVATE_PARTITION(part, xpcNoHeartbeat);
 423                         continue;
 424                 }
 425
 426                 part->last_heartbeat = remote_vars->heartbeat;
 427         }
 428 }
 429
 430
 431 /*
 432  * Get a copy of the remote partition's rsvd page.
 433  *
 434  * remote_rp points to a buffer that is cacheline aligned for BTE copies and
 435  * assumed to be of size XPC_RSVD_PAGE_ALIGNED_SIZE.
 436  */
 437 static enum xpc_retval
 438 xpc_get_remote_rp(int nasid, u64 *discovered_nasids,
 439                 struct xpc_rsvd_page *remote_rp, u64 *remote_rsvd_page_pa)
 440 {
 441         int bres, i;
 442
 443
 444         /* get the reserved page's physical address */
 445
 446         *remote_rsvd_page_pa = xpc_get_rsvd_page_pa(nasid, (u64) remote_rp,
 447                                                 XPC_RSVD_PAGE_ALIGNED_SIZE);
 448         if (*remote_rsvd_page_pa == 0) {
 449                 return xpcNoRsvdPageAddr;
 450         }
 451
 452
 453         /* pull over the reserved page structure */
 454
 455         bres = xp_bte_copy(*remote_rsvd_page_pa, ia64_tpa((u64) remote_rp),
 456                                 XPC_RSVD_PAGE_ALIGNED_SIZE,
 457                                 (BTE_NOTIFY | BTE_WACQUIRE), NULL);
 458         if (bres != BTE_SUCCESS) {
 459                 return xpc_map_bte_errors(bres);
 460         }
 461
 462
 463         if (discovered_nasids != NULL) {
 464                 for (i = 0; i < XP_NASID_MASK_WORDS; i++) {
 465                         discovered_nasids[i] |= remote_rp->part_nasids[i];
 466                 }
 467         }
 468
 469
 470         /* check that the partid is for another partition */
 471
 472         if (remote_rp->partid < 1 ||
 473                                 remote_rp->partid > (XP_MAX_PARTITIONS - 1)) {
 474                 return xpcInvalidPartid;
 475         }
 476
 477         if (remote_rp->partid == sn_partition_id) {
 478                 return xpcLocalPartid;
 479         }
 480
 481
 482         if (XPC_VERSION_MAJOR(remote_rp->version) !=
 483                                         XPC_VERSION_MAJOR(XPC_RP_VERSION)) {
 484                 return xpcBadVersion;
 485         }
 486
 487         return xpcSuccess;
 488 }
 489
 490
 491 /*
 492  * Get a copy of the remote partition's XPC variables.
 493  *
 494  * remote_vars points to a buffer that is cacheline aligned for BTE copies and
 495  * assumed to be of size XPC_VARS_ALIGNED_SIZE.
 496  */
 497 static enum xpc_retval
 498 xpc_get_remote_vars(u64 remote_vars_pa, struct xpc_vars *remote_vars)
 499 {
 500         int bres;
 501
 502
 503         if (remote_vars_pa == 0) {
 504                 return xpcVarsNotSet;
 505         }
 506
 507
 508         /* pull over the cross partition variables */
 509
 510         bres = xp_bte_copy(remote_vars_pa, ia64_tpa((u64) remote_vars),
 511                                 XPC_VARS_ALIGNED_SIZE,
 512                                 (BTE_NOTIFY | BTE_WACQUIRE), NULL);
 513         if (bres != BTE_SUCCESS) {
 514                 return xpc_map_bte_errors(bres);
 515         }
 516
 517         if (XPC_VERSION_MAJOR(remote_vars->version) !=
 518                                         XPC_VERSION_MAJOR(XPC_V_VERSION)) {
 519                 return xpcBadVersion;
 520         }
 521
 522         return xpcSuccess;
 523 }
 524
 525
 526 /*
 527  * Prior code has determine the nasid which generated an IPI.  Inspect
 528  * that nasid to determine if its partition needs to be activated or
 529  * deactivated.
 530  *
 531  * A partition is consider "awaiting activation" if our partition
 532  * flags indicate it is not active and it has a heartbeat.  A
 533  * partition is considered "awaiting deactivation" if our partition
 534  * flags indicate it is active but it has no heartbeat or it is not
 535  * sending its heartbeat to us.
 536  *
 537  * To determine the heartbeat, the remote nasid must have a properly
 538  * initialized reserved page.
 539  */
 540 static void
 541 xpc_identify_act_IRQ_req(int nasid)
 542 {
 543         struct xpc_rsvd_page *remote_rp;
 544         struct xpc_vars *remote_vars;
 545         u64 remote_rsvd_page_pa;
 546         u64 remote_vars_pa;
 547         partid_t partid;
 548         struct xpc_partition *part;
 549         enum xpc_retval ret;
 550
 551
 552         /* pull over the reserved page structure */
 553
 554         remote_rp = (struct xpc_rsvd_page *) xpc_remote_copy_buffer;
 555
 556         ret = xpc_get_remote_rp(nasid, NULL, remote_rp, &remote_rsvd_page_pa);
 557         if (ret != xpcSuccess) {
 558                 dev_warn(xpc_part, "unable to get reserved page from nasid %d, "
 559                         "which sent interrupt, reason=%d\n", nasid, ret);
 560                 return;
 561         }
 562
 563         remote_vars_pa = remote_rp->vars_pa;
 564         partid = remote_rp->partid;
 565         part = &xpc_partitions[partid];
 566
 567
 568         /* pull over the cross partition variables */
 569
 570         remote_vars = (struct xpc_vars *) xpc_remote_copy_buffer;
 571
 572         ret = xpc_get_remote_vars(remote_vars_pa, remote_vars);
 573         if (ret != xpcSuccess) {
 574
 575                 dev_warn(xpc_part, "unable to get XPC variables from nasid %d, "
 576                         "which sent interrupt, reason=%d\n", nasid, ret);
 577
 578                 XPC_DEACTIVATE_PARTITION(part, ret);
 579                 return;
 580         }
 581
 582
 583         part->act_IRQ_rcvd++;
 584
 585         dev_dbg(xpc_part, "partid for nasid %d is %d; IRQs = %d; HB = "
 586                 "%ld:0x%lx\n", (int) nasid, (int) partid, part->act_IRQ_rcvd,
 587                 remote_vars->heartbeat, remote_vars->heartbeating_to_mask);
 588
 589
 590         if (part->act_state == XPC_P_INACTIVE) {
 591
 592                 part->remote_rp_pa = remote_rsvd_page_pa;
 593                 dev_dbg(xpc_part, "  remote_rp_pa = 0x%016lx\n",
 594                         part->remote_rp_pa);
 595
 596                 part->remote_vars_pa = remote_vars_pa;
 597                 dev_dbg(xpc_part, "  remote_vars_pa = 0x%016lx\n",
 598                         part->remote_vars_pa);
 599
 600                 part->last_heartbeat = remote_vars->heartbeat;
 601                 dev_dbg(xpc_part, "  last_heartbeat = 0x%016lx\n",
 602                         part->last_heartbeat);
 603
 604                 part->remote_vars_part_pa = remote_vars->vars_part_pa;
 605                 dev_dbg(xpc_part, "  remote_vars_part_pa = 0x%016lx\n",
 606                         part->remote_vars_part_pa);
 607
 608                 part->remote_act_nasid = remote_vars->act_nasid;
 609                 dev_dbg(xpc_part, "  remote_act_nasid = 0x%x\n",
 610                         part->remote_act_nasid);
 611
 612                 part->remote_act_phys_cpuid = remote_vars->act_phys_cpuid;
 613                 dev_dbg(xpc_part, "  remote_act_phys_cpuid = 0x%x\n",
 614                         part->remote_act_phys_cpuid);
 615
 616                 part->remote_amos_page_pa = remote_vars->amos_page_pa;
 617                 dev_dbg(xpc_part, "  remote_amos_page_pa = 0x%lx\n",
 618                         part->remote_amos_page_pa);
 619
 620                 xpc_activate_partition(part);
 621
 622         } else if (part->remote_amos_page_pa != remote_vars->amos_page_pa ||
 623                         !XPC_HB_ALLOWED(sn_partition_id, remote_vars)) {
 624
 625                 part->reactivate_nasid = nasid;
 626                 XPC_DEACTIVATE_PARTITION(part, xpcReactivating);
 627         }
 628 }
 629
 630
 631 /*
 632  * Loop through the activation AMO variables and process any bits
 633  * which are set.  Each bit indicates a nasid sending a partition
 634  * activation or deactivation request.
 635  *
 636  * Return #of IRQs detected.
 637  */
 638 int
 639 xpc_identify_act_IRQ_sender(void)
 640 {
 641         int word, bit;
 642         u64 nasid_mask;
 643         u64 nasid;                      /* remote nasid */
 644         int n_IRQs_detected = 0;
 645         AMO_t *act_amos;
 646         struct xpc_rsvd_page *rp = (struct xpc_rsvd_page *) xpc_rsvd_page;
 647
 648
 649         act_amos = xpc_vars->act_amos;
 650
 651
 652         /* scan through act AMO variable looking for non-zero entries */
 653         for (word = 0; word < XP_NASID_MASK_WORDS; word++) {
 654
 655                 nasid_mask = xpc_IPI_receive(&act_amos[word]);
 656                 if (nasid_mask == 0) {
 657                         /* no IRQs from nasids in this variable */
 658                         continue;
 659                 }
 660
 661                 dev_dbg(xpc_part, "AMO[%d] gave back 0x%lx\n", word,
 662                         nasid_mask);
 663
 664
 665                 /*
 666                  * If this nasid has been added to the machine since
 667                  * our partition was reset, this will retain the
 668                  * remote nasid in our reserved pages machine mask.
 669                  * This is used in the event of module reload.
 670                  */
 671                 rp->mach_nasids[word] |= nasid_mask;
 672
 673
 674                 /* locate the nasid(s) which sent interrupts */
 675
 676                 for (bit = 0; bit < (8 * sizeof(u64)); bit++) {
 677                         if (nasid_mask & (1UL << bit)) {
 678                                 n_IRQs_detected++;
 679                                 nasid = XPC_NASID_FROM_W_B(word, bit);
 680                                 dev_dbg(xpc_part, "interrupt from nasid %ld\n",
 681                                         nasid);
 682                                 xpc_identify_act_IRQ_req(nasid);
 683                         }
 684                 }
 685         }
 686         return n_IRQs_detected;
 687 }
 688
 689
 690 /*
 691  * Mark specified partition as active.
 692  */
 693 enum xpc_retval
 694 xpc_mark_partition_active(struct xpc_partition *part)
 695 {
 696         unsigned long irq_flags;
 697         enum xpc_retval ret;
 698
 699
 700         dev_dbg(xpc_part, "setting partition %d to ACTIVE\n", XPC_PARTID(part));
 701
 702         spin_lock_irqsave(&part->act_lock, irq_flags);
 703         if (part->act_state == XPC_P_ACTIVATING) {
 704                 part->act_state = XPC_P_ACTIVE;
 705                 ret = xpcSuccess;
 706         } else {
 707                 DBUG_ON(part->reason == xpcSuccess);
 708                 ret = part->reason;
 709         }
 710         spin_unlock_irqrestore(&part->act_lock, irq_flags);
 711
 712         return ret;
 713 }
 714
 715
 716 /*
 717  * Notify XPC that the partition is down.
 718  */
 719 void
 720 xpc_deactivate_partition(const int line, struct xpc_partition *part,
 721                                 enum xpc_retval reason)
 722 {
 723         unsigned long irq_flags;
 724         partid_t partid = XPC_PARTID(part);
 725
 726
 727         spin_lock_irqsave(&part->act_lock, irq_flags);
 728
 729         if (part->act_state == XPC_P_INACTIVE) {
 730                 XPC_SET_REASON(part, reason, line);
 731                 spin_unlock_irqrestore(&part->act_lock, irq_flags);
 732                 if (reason == xpcReactivating) {
 733                         /* we interrupt ourselves to reactivate partition */
 734                         xpc_IPI_send_reactivate(part);
 735                 }
 736                 return;
 737         }
 738         if (part->act_state == XPC_P_DEACTIVATING) {
 739                 if ((part->reason == xpcUnloading && reason != xpcUnloading) ||
 740                                         reason == xpcReactivating) {
 741                         XPC_SET_REASON(part, reason, line);
 742                 }
 743                 spin_unlock_irqrestore(&part->act_lock, irq_flags);
 744                 return;
 745         }
 746
 747         part->act_state = XPC_P_DEACTIVATING;
 748         XPC_SET_REASON(part, reason, line);
 749
 750         spin_unlock_irqrestore(&part->act_lock, irq_flags);
 751
 752         XPC_DISALLOW_HB(partid, xpc_vars);
 753
 754         dev_dbg(xpc_part, "bringing partition %d down, reason = %d\n", partid,
 755                 reason);
 756
 757         xpc_partition_down(part, reason);
 758 }
 759
 760
 761 /*
 762  * Mark specified partition as active.
 763  */
 764 void
 765 xpc_mark_partition_inactive(struct xpc_partition *part)
 766 {
 767         unsigned long irq_flags;
 768
 769
 770         dev_dbg(xpc_part, "setting partition %d to INACTIVE\n",
 771                 XPC_PARTID(part));
 772
 773         spin_lock_irqsave(&part->act_lock, irq_flags);
 774         part->act_state = XPC_P_INACTIVE;
 775         spin_unlock_irqrestore(&part->act_lock, irq_flags);
 776         part->remote_rp_pa = 0;
 777 }
 778
 779
 780 /*
 781  * SAL has provided a partition and machine mask.  The partition mask
 782  * contains a bit for each even nasid in our partition.  The machine
 783  * mask contains a bit for each even nasid in the entire machine.
 784  *
 785  * Using those two bit arrays, we can determine which nasids are
 786  * known in the machine.  Each should also have a reserved page
 787  * initialized if they are available for partitioning.
 788  */
 789 void
 790 xpc_discovery(void)
 791 {
 792         void *remote_rp_base;
 793         struct xpc_rsvd_page *remote_rp;
 794         struct xpc_vars *remote_vars;
 795         u64 remote_rsvd_page_pa;
 796         u64 remote_vars_pa;
 797         int region;
 798         int max_regions;
 799         int nasid;
 800         struct xpc_rsvd_page *rp;
 801         partid_t partid;
 802         struct xpc_partition *part;
 803         u64 *discovered_nasids;
 804         enum xpc_retval ret;
 805
 806
 807         remote_rp = xpc_kmalloc_cacheline_aligned(XPC_RSVD_PAGE_ALIGNED_SIZE,
 808                                                 GFP_KERNEL, &remote_rp_base);
 809         if (remote_rp == NULL) {
 810                 return;
 811         }
 812         remote_vars = (struct xpc_vars *) remote_rp;
 813
 814
 815         discovered_nasids = kmalloc(sizeof(u64) * XP_NASID_MASK_WORDS,
 816                                                         GFP_KERNEL);
 817         if (discovered_nasids == NULL) {
 818                 kfree(remote_rp_base);
 819                 return;
 820         }
 821         memset(discovered_nasids, 0, sizeof(u64) * XP_NASID_MASK_WORDS);
 822
 823         rp = (struct xpc_rsvd_page *) xpc_rsvd_page;
 824
 825         /*
 826          * The term 'region' in this context refers to the minimum number of
 827          * nodes that can comprise an access protection grouping. The access
 828          * protection is in regards to memory, IOI and IPI.
 829          */
 830 //>>> move the next two #defines into either include/asm-ia64/sn/arch.h or
 831 //>>> include/asm-ia64/sn/addrs.h
 832 #define SH1_MAX_REGIONS         64
 833 #define SH2_MAX_REGIONS         256
 834         max_regions = is_shub2() ? SH2_MAX_REGIONS : SH1_MAX_REGIONS;
 835
 836         for (region = 0; region < max_regions; region++) {
 837
 838                 if ((volatile int) xpc_exiting) {
 839                         break;
 840                 }
 841
 842                 dev_dbg(xpc_part, "searching region %d\n", region);
 843
 844                 for (nasid = (region * sn_region_size * 2);
 845                      nasid < ((region + 1) * sn_region_size * 2);
 846                      nasid += 2) {
 847
 848                         if ((volatile int) xpc_exiting) {
 849                                 break;
 850                         }
 851
 852                         dev_dbg(xpc_part, "checking nasid %d\n", nasid);
 853
 854
 855                         if (XPC_NASID_IN_ARRAY(nasid, rp->part_nasids)) {
 856                                 dev_dbg(xpc_part, "PROM indicates Nasid %d is "
 857                                         "part of the local partition; skipping "
 858                                         "region\n", nasid);
 859                                 break;
 860                         }
 861
 862                         if (!(XPC_NASID_IN_ARRAY(nasid, rp->mach_nasids))) {
 863                                 dev_dbg(xpc_part, "PROM indicates Nasid %d was "
 864                                         "not on Numa-Link network at reset\n",
 865                                         nasid);
 866                                 continue;
 867                         }
 868
 869                         if (XPC_NASID_IN_ARRAY(nasid, discovered_nasids)) {
 870                                 dev_dbg(xpc_part, "Nasid %d is part of a "
 871                                         "partition which was previously "
 872                                         "discovered\n", nasid);
 873                                 continue;
 874                         }
 875
 876
 877                         /* pull over the reserved page structure */
 878
 879                         ret = xpc_get_remote_rp(nasid, discovered_nasids,
 880                                               remote_rp, &remote_rsvd_page_pa);
 881                         if (ret != xpcSuccess) {
 882                                 dev_dbg(xpc_part, "unable to get reserved page "
 883                                         "from nasid %d, reason=%d\n", nasid,
 884                                         ret);
 885
 886                                 if (ret == xpcLocalPartid) {
 887                                         break;
 888                                 }
 889                                 continue;
 890                         }
 891
 892                         remote_vars_pa = remote_rp->vars_pa;
 893
 894                         partid = remote_rp->partid;
 895                         part = &xpc_partitions[partid];
 896
 897
 898                         /* pull over the cross partition variables */
 899
 900                         ret = xpc_get_remote_vars(remote_vars_pa, remote_vars);
 901                         if (ret != xpcSuccess) {
 902                                 dev_dbg(xpc_part, "unable to get XPC variables "
 903                                         "from nasid %d, reason=%d\n", nasid,
 904                                         ret);
 905
 906                                 XPC_DEACTIVATE_PARTITION(part, ret);
 907                                 continue;
 908                         }
 909
 910                         if (part->act_state != XPC_P_INACTIVE) {
 911                                 dev_dbg(xpc_part, "partition %d on nasid %d is "
 912                                         "already activating\n", partid, nasid);
 913                                 break;
 914                         }
 915
 916                         /*
 917                          * Register the remote partition's AMOs with SAL so it
 918                          * can handle and cleanup errors within that address
 919                          * range should the remote partition go down. We don't
 920                          * unregister this range because it is difficult to
 921                          * tell when outstanding writes to the remote partition
 922                          * are finished and thus when it is thus safe to
 923                          * unregister. This should not result in wasted space
 924                          * in the SAL xp_addr_region table because we should
 925                          * get the same page for remote_act_amos_pa after
 926                          * module reloads and system reboots.
 927                          */
 928                         if (sn_register_xp_addr_region(
 929                                             remote_vars->amos_page_pa,
 930                                                         PAGE_SIZE, 1) < 0) {
 931                                 dev_dbg(xpc_part, "partition %d failed to "
 932                                         "register xp_addr region 0x%016lx\n",
 933                                         partid, remote_vars->amos_page_pa);
 934
 935                                 XPC_SET_REASON(part, xpcPhysAddrRegFailed,
 936                                                 __LINE__);
 937                                 break;
 938                         }
 939
 940                         /*
 941                          * The remote nasid is valid and available.
 942                          * Send an interrupt to that nasid to notify
 943                          * it that we are ready to begin activation.
 944                          */
 945                         dev_dbg(xpc_part, "sending an interrupt to AMO 0x%lx, "
 946                                 "nasid %d, phys_cpuid 0x%x\n",
 947                                 remote_vars->amos_page_pa,
 948                                 remote_vars->act_nasid,
 949                                 remote_vars->act_phys_cpuid);
 950
 951                         xpc_IPI_send_activate(remote_vars);
 952                 }
 953         }
 954
 955         kfree(discovered_nasids);
 956         kfree(remote_rp_base);
 957 }
 958
 959
 960 /*
 961  * Given a partid, get the nasids owned by that partition from the
 962  * remote partition's reserved page.
 963  */
 964 enum xpc_retval
 965 xpc_initiate_partid_to_nasids(partid_t partid, void *nasid_mask)
 966 {
 967         struct xpc_partition *part;
 968         u64 part_nasid_pa;
 969         int bte_res;
 970
 971
 972         part = &xpc_partitions[partid];
 973         if (part->remote_rp_pa == 0) {
 974                 return xpcPartitionDown;
 975         }
 976
 977         part_nasid_pa = part->remote_rp_pa +
 978                 (u64) &((struct xpc_rsvd_page *) 0)->part_nasids;
 979
 980         bte_res = xp_bte_copy(part_nasid_pa, ia64_tpa((u64) nasid_mask),
 981                                 L1_CACHE_ALIGN(XP_NASID_MASK_BYTES),
 982                                 (BTE_NOTIFY | BTE_WACQUIRE), NULL);
 983
 984         return xpc_map_bte_errors(bte_res);
 985 }
 986