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