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