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) 2004-2008 Silicon Graphics, Inc. All Rights Reserved. 7 */ 8 9/* 10 * Cross Partition Communication (XPC) partition support. 11 * 12 * This is the part of XPC that detects the presence/absence of 13 * other partitions. It provides a heartbeat and monitors the 14 * heartbeats of other partitions. 15 * 16 */ 17 18#include <linux/device.h> 19#include <linux/hardirq.h> 20#include <linux/slab.h> 21#include "xpc.h" 22#include <asm/uv/uv_hub.h> 23 24/* XPC is exiting flag */ 25int xpc_exiting; 26 27/* this partition's reserved page pointers */ 28struct xpc_rsvd_page *xpc_rsvd_page; 29static unsigned long *xpc_part_nasids; 30unsigned long *xpc_mach_nasids; 31 32static int xpc_nasid_mask_nbytes; /* #of bytes in nasid mask */ 33int xpc_nasid_mask_nlongs; /* #of longs in nasid mask */ 34 35struct xpc_partition *xpc_partitions; 36 37/* 38 * Guarantee that the kmalloc'd memory is cacheline aligned. 39 */ 40void * 41xpc_kmalloc_cacheline_aligned(size_t size, gfp_t flags, void **base) 42{ 43 /* see if kmalloc will give us cachline aligned memory by default */ 44 *base = kmalloc(size, flags); 45 if (*base == NULL) 46 return NULL; 47 48 if ((u64)*base == L1_CACHE_ALIGN((u64)*base)) 49 return *base; 50 51 kfree(*base); 52 53 /* nope, we'll have to do it ourselves */ 54 *base = kmalloc(size + L1_CACHE_BYTES, flags); 55 if (*base == NULL) 56 return NULL; 57 58 return (void *)L1_CACHE_ALIGN((u64)*base); 59} 60 61/* 62 * Given a nasid, get the physical address of the partition's reserved page 63 * for that nasid. This function returns 0 on any error. 64 */ 65static unsigned long 66xpc_get_rsvd_page_pa(int nasid) 67{ 68 enum xp_retval ret; 69 u64 cookie = 0; 70 unsigned long rp_pa = nasid; /* seed with nasid */ 71 size_t len = 0; 72 size_t buf_len = 0; 73 void *buf = buf; 74 void *buf_base = NULL; 75 enum xp_retval (*get_partition_rsvd_page_pa) 76 (void *, u64 *, unsigned long *, size_t *) = 77 xpc_arch_ops.get_partition_rsvd_page_pa; 78 79 while (1) { 80 81 /* !!! rp_pa will need to be _gpa on UV. 82 * ??? So do we save it into the architecture specific parts 83 * ??? of the xpc_partition structure? Do we rename this 84 * ??? function or have two versions? Rename rp_pa for UV to 85 * ??? rp_gpa? 86 */ 87 ret = get_partition_rsvd_page_pa(buf, &cookie, &rp_pa, &len); 88 89 dev_dbg(xpc_part, "SAL returned with ret=%d, cookie=0x%016lx, " 90 "address=0x%016lx, len=0x%016lx\n", ret, 91 (unsigned long)cookie, rp_pa, len); 92 93 if (ret != xpNeedMoreInfo) 94 break; 95 96 /* !!! L1_CACHE_ALIGN() is only a sn2-bte_copy requirement */ 97 if (is_shub()) 98 len = L1_CACHE_ALIGN(len); 99 100 if (len > buf_len) { 101 if (buf_base != NULL) 102 kfree(buf_base); 103 buf_len = L1_CACHE_ALIGN(len); 104 buf = xpc_kmalloc_cacheline_aligned(buf_len, GFP_KERNEL, 105 &buf_base); 106 if (buf_base == NULL) { 107 dev_err(xpc_part, "unable to kmalloc " 108 "len=0x%016lx\n", buf_len); 109 ret = xpNoMemory; 110 break; 111 } 112 } 113 114 ret = xp_remote_memcpy(xp_pa(buf), rp_pa, len); 115 if (ret != xpSuccess) { 116 dev_dbg(xpc_part, "xp_remote_memcpy failed %d\n", ret); 117 break; 118 } 119 } 120 121 kfree(buf_base); 122 123 if (ret != xpSuccess) 124 rp_pa = 0; 125 126 dev_dbg(xpc_part, "reserved page at phys address 0x%016lx\n", rp_pa); 127 return rp_pa; 128} 129 130/* 131 * Fill the partition reserved page with the information needed by 132 * other partitions to discover we are alive and establish initial 133 * communications. 134 */ 135int 136xpc_setup_rsvd_page(void) 137{ 138 int ret; 139 struct xpc_rsvd_page *rp; 140 unsigned long rp_pa; 141 unsigned long new_ts_jiffies; 142 143 /* get the local reserved page's address */ 144 145 preempt_disable(); 146 rp_pa = xpc_get_rsvd_page_pa(xp_cpu_to_nasid(smp_processor_id())); 147 preempt_enable(); 148 if (rp_pa == 0) { 149 dev_err(xpc_part, "SAL failed to locate the reserved page\n"); 150 return -ESRCH; 151 } 152 rp = (struct xpc_rsvd_page *)__va(xp_socket_pa(rp_pa)); 153 154 if (rp->SAL_version < 3) { 155 /* SAL_versions < 3 had a SAL_partid defined as a u8 */ 156 rp->SAL_partid &= 0xff; 157 } 158 BUG_ON(rp->SAL_partid != xp_partition_id); 159 160 if (rp->SAL_partid < 0 || rp->SAL_partid >= xp_max_npartitions) { 161 dev_err(xpc_part, "the reserved page's partid of %d is outside " 162 "supported range (< 0 || >= %d)\n", rp->SAL_partid, 163 xp_max_npartitions); 164 return -EINVAL; 165 } 166 167 rp->version = XPC_RP_VERSION; 168 rp->max_npartitions = xp_max_npartitions; 169 170 /* establish the actual sizes of the nasid masks */ 171 if (rp->SAL_version == 1) { 172 /* SAL_version 1 didn't set the nasids_size field */ 173 rp->SAL_nasids_size = 128; 174 } 175 xpc_nasid_mask_nbytes = rp->SAL_nasids_size; 176 xpc_nasid_mask_nlongs = BITS_TO_LONGS(rp->SAL_nasids_size * 177 BITS_PER_BYTE); 178 179 /* setup the pointers to the various items in the reserved page */ 180 xpc_part_nasids = XPC_RP_PART_NASIDS(rp); 181 xpc_mach_nasids = XPC_RP_MACH_NASIDS(rp); 182 183 ret = xpc_arch_ops.setup_rsvd_page(rp); 184 if (ret != 0) 185 return ret; 186 187 /* 188 * Set timestamp of when reserved page was setup by XPC. 189 * This signifies to the remote partition that our reserved 190 * page is initialized. 191 */ 192 new_ts_jiffies = jiffies; 193 if (new_ts_jiffies == 0 || new_ts_jiffies == rp->ts_jiffies) 194 new_ts_jiffies++; 195 rp->ts_jiffies = new_ts_jiffies; 196 197 xpc_rsvd_page = rp; 198 return 0; 199} 200 201void 202xpc_teardown_rsvd_page(void) 203{ 204 /* a zero timestamp indicates our rsvd page is not initialized */ 205 xpc_rsvd_page->ts_jiffies = 0; 206} 207 208/* 209 * Get a copy of a portion of the remote partition's rsvd page. 210 * 211 * remote_rp points to a buffer that is cacheline aligned for BTE copies and 212 * is large enough to contain a copy of their reserved page header and 213 * part_nasids mask. 214 */ 215enum xp_retval 216xpc_get_remote_rp(int nasid, unsigned long *discovered_nasids, 217 struct xpc_rsvd_page *remote_rp, unsigned long *remote_rp_pa) 218{ 219 int l; 220 enum xp_retval ret; 221 222 /* get the reserved page's physical address */ 223 224 *remote_rp_pa = xpc_get_rsvd_page_pa(nasid); 225 if (*remote_rp_pa == 0) 226 return xpNoRsvdPageAddr; 227 228 /* pull over the reserved page header and part_nasids mask */ 229 ret = xp_remote_memcpy(xp_pa(remote_rp), *remote_rp_pa, 230 XPC_RP_HEADER_SIZE + xpc_nasid_mask_nbytes); 231 if (ret != xpSuccess) 232 return ret; 233 234 if (discovered_nasids != NULL) { 235 unsigned long *remote_part_nasids = 236 XPC_RP_PART_NASIDS(remote_rp); 237 238 for (l = 0; l < xpc_nasid_mask_nlongs; l++) 239 discovered_nasids[l] |= remote_part_nasids[l]; 240 } 241 242 /* zero timestamp indicates the reserved page has not been setup */ 243 if (remote_rp->ts_jiffies == 0) 244 return xpRsvdPageNotSet; 245 246 if (XPC_VERSION_MAJOR(remote_rp->version) != 247 XPC_VERSION_MAJOR(XPC_RP_VERSION)) { 248 return xpBadVersion; 249 } 250 251 /* check that both remote and local partids are valid for each side */ 252 if (remote_rp->SAL_partid < 0 || 253 remote_rp->SAL_partid >= xp_max_npartitions || 254 remote_rp->max_npartitions <= xp_partition_id) { 255 return xpInvalidPartid; 256 } 257 258 if (remote_rp->SAL_partid == xp_partition_id) 259 return xpLocalPartid; 260 261 return xpSuccess; 262} 263 264/* 265 * See if the other side has responded to a partition deactivate request 266 * from us. Though we requested the remote partition to deactivate with regard 267 * to us, we really only need to wait for the other side to disengage from us. 268 */ 269int 270xpc_partition_disengaged(struct xpc_partition *part) 271{ 272 short partid = XPC_PARTID(part); 273 int disengaged; 274 275 disengaged = !xpc_arch_ops.partition_engaged(partid); 276 if (part->disengage_timeout) { 277 if (!disengaged) { 278 if (time_is_after_jiffies(part->disengage_timeout)) { 279 /* timelimit hasn't been reached yet */ 280 return 0; 281 } 282 283 /* 284 * Other side hasn't responded to our deactivate 285 * request in a timely fashion, so assume it's dead. 286 */ 287 288 dev_info(xpc_part, "deactivate request to remote " 289 "partition %d timed out\n", partid); 290 xpc_disengage_timedout = 1; 291 xpc_arch_ops.assume_partition_disengaged(partid); 292 disengaged = 1; 293 } 294 part->disengage_timeout = 0; 295 296 /* cancel the timer function, provided it's not us */ 297 if (!in_interrupt()) 298 del_singleshot_timer_sync(&part->disengage_timer); 299 300 DBUG_ON(part->act_state != XPC_P_AS_DEACTIVATING && 301 part->act_state != XPC_P_AS_INACTIVE); 302 if (part->act_state != XPC_P_AS_INACTIVE) 303 xpc_wakeup_channel_mgr(part); 304 305 xpc_arch_ops.cancel_partition_deactivation_request(part); 306 } 307 return disengaged; 308} 309 310/* 311 * Mark specified partition as active. 312 */ 313enum xp_retval 314xpc_mark_partition_active(struct xpc_partition *part) 315{ 316 unsigned long irq_flags; 317 enum xp_retval ret; 318 319 dev_dbg(xpc_part, "setting partition %d to ACTIVE\n", XPC_PARTID(part)); 320 321 spin_lock_irqsave(&part->act_lock, irq_flags); 322 if (part->act_state == XPC_P_AS_ACTIVATING) { 323 part->act_state = XPC_P_AS_ACTIVE; 324 ret = xpSuccess; 325 } else { 326 DBUG_ON(part->reason == xpSuccess); 327 ret = part->reason; 328 } 329 spin_unlock_irqrestore(&part->act_lock, irq_flags); 330 331 return ret; 332} 333 334/* 335 * Start the process of deactivating the specified partition. 336 */ 337void 338xpc_deactivate_partition(const int line, struct xpc_partition *part, 339 enum xp_retval reason) 340{ 341 unsigned long irq_flags; 342 343 spin_lock_irqsave(&part->act_lock, irq_flags); 344 345 if (part->act_state == XPC_P_AS_INACTIVE) { 346 XPC_SET_REASON(part, reason, line); 347 spin_unlock_irqrestore(&part->act_lock, irq_flags); 348 if (reason == xpReactivating) { 349 /* we interrupt ourselves to reactivate partition */ 350 xpc_arch_ops.request_partition_reactivation(part); 351 } 352 return; 353 } 354 if (part->act_state == XPC_P_AS_DEACTIVATING) { 355 if ((part->reason == xpUnloading && reason != xpUnloading) || 356 reason == xpReactivating) { 357 XPC_SET_REASON(part, reason, line); 358 } 359 spin_unlock_irqrestore(&part->act_lock, irq_flags); 360 return; 361 } 362 363 part->act_state = XPC_P_AS_DEACTIVATING; 364 XPC_SET_REASON(part, reason, line); 365 366 spin_unlock_irqrestore(&part->act_lock, irq_flags); 367 368 /* ask remote partition to deactivate with regard to us */ 369 xpc_arch_ops.request_partition_deactivation(part); 370 371 /* set a timelimit on the disengage phase of the deactivation request */ 372 part->disengage_timeout = jiffies + (xpc_disengage_timelimit * HZ); 373 part->disengage_timer.expires = part->disengage_timeout; 374 add_timer(&part->disengage_timer); 375 376 dev_dbg(xpc_part, "bringing partition %d down, reason = %d\n", 377 XPC_PARTID(part), reason); 378 379 xpc_partition_going_down(part, reason); 380} 381 382/* 383 * Mark specified partition as inactive. 384 */ 385void 386xpc_mark_partition_inactive(struct xpc_partition *part) 387{ 388 unsigned long irq_flags; 389 390 dev_dbg(xpc_part, "setting partition %d to INACTIVE\n", 391 XPC_PARTID(part)); 392 393 spin_lock_irqsave(&part->act_lock, irq_flags); 394 part->act_state = XPC_P_AS_INACTIVE; 395 spin_unlock_irqrestore(&part->act_lock, irq_flags); 396 part->remote_rp_pa = 0; 397} 398 399/* 400 * SAL has provided a partition and machine mask. The partition mask 401 * contains a bit for each even nasid in our partition. The machine 402 * mask contains a bit for each even nasid in the entire machine. 403 * 404 * Using those two bit arrays, we can determine which nasids are 405 * known in the machine. Each should also have a reserved page 406 * initialized if they are available for partitioning. 407 */ 408void 409xpc_discovery(void) 410{ 411 void *remote_rp_base; 412 struct xpc_rsvd_page *remote_rp; 413 unsigned long remote_rp_pa; 414 int region; 415 int region_size; 416 int max_regions; 417 int nasid; 418 struct xpc_rsvd_page *rp; 419 unsigned long *discovered_nasids; 420 enum xp_retval ret; 421 422 remote_rp = xpc_kmalloc_cacheline_aligned(XPC_RP_HEADER_SIZE + 423 xpc_nasid_mask_nbytes, 424 GFP_KERNEL, &remote_rp_base); 425 if (remote_rp == NULL) 426 return; 427 428 discovered_nasids = kzalloc(sizeof(long) * xpc_nasid_mask_nlongs, 429 GFP_KERNEL); 430 if (discovered_nasids == NULL) { 431 kfree(remote_rp_base); 432 return; 433 } 434 435 rp = (struct xpc_rsvd_page *)xpc_rsvd_page; 436 437 /* 438 * The term 'region' in this context refers to the minimum number of 439 * nodes that can comprise an access protection grouping. The access 440 * protection is in regards to memory, IOI and IPI. 441 */ 442 region_size = xp_region_size; 443 444 if (is_uv()) 445 max_regions = 256; 446 else { 447 max_regions = 64; 448 449 switch (region_size) { 450 case 128: 451 max_regions *= 2; 452 case 64: 453 max_regions *= 2; 454 case 32: 455 max_regions *= 2; 456 region_size = 16; 457 DBUG_ON(!is_shub2()); 458 } 459 } 460 461 for (region = 0; region < max_regions; region++) { 462 463 if (xpc_exiting) 464 break; 465 466 dev_dbg(xpc_part, "searching region %d\n", region); 467 468 for (nasid = (region * region_size * 2); 469 nasid < ((region + 1) * region_size * 2); nasid += 2) { 470 471 if (xpc_exiting) 472 break; 473 474 dev_dbg(xpc_part, "checking nasid %d\n", nasid); 475 476 if (test_bit(nasid / 2, xpc_part_nasids)) { 477 dev_dbg(xpc_part, "PROM indicates Nasid %d is " 478 "part of the local partition; skipping " 479 "region\n", nasid); 480 break; 481 } 482 483 if (!(test_bit(nasid / 2, xpc_mach_nasids))) { 484 dev_dbg(xpc_part, "PROM indicates Nasid %d was " 485 "not on Numa-Link network at reset\n", 486 nasid); 487 continue; 488 } 489 490 if (test_bit(nasid / 2, discovered_nasids)) { 491 dev_dbg(xpc_part, "Nasid %d is part of a " 492 "partition which was previously " 493 "discovered\n", nasid); 494 continue; 495 } 496 497 /* pull over the rsvd page header & part_nasids mask */ 498 499 ret = xpc_get_remote_rp(nasid, discovered_nasids, 500 remote_rp, &remote_rp_pa); 501 if (ret != xpSuccess) { 502 dev_dbg(xpc_part, "unable to get reserved page " 503 "from nasid %d, reason=%d\n", nasid, 504 ret); 505 506 if (ret == xpLocalPartid) 507 break; 508 509 continue; 510 } 511 512 xpc_arch_ops.request_partition_activation(remote_rp, 513 remote_rp_pa, nasid); 514 } 515 } 516 517 kfree(discovered_nasids); 518 kfree(remote_rp_base); 519} 520 521/* 522 * Given a partid, get the nasids owned by that partition from the 523 * remote partition's reserved page. 524 */ 525enum xp_retval 526xpc_initiate_partid_to_nasids(short partid, void *nasid_mask) 527{ 528 struct xpc_partition *part; 529 unsigned long part_nasid_pa; 530 531 part = &xpc_partitions[partid]; 532 if (part->remote_rp_pa == 0) 533 return xpPartitionDown; 534 535 memset(nasid_mask, 0, xpc_nasid_mask_nbytes); 536 537 part_nasid_pa = (unsigned long)XPC_RP_PART_NASIDS(part->remote_rp_pa); 538 539 return xp_remote_memcpy(xp_pa(nasid_mask), part_nasid_pa, 540 xpc_nasid_mask_nbytes); 541} 542