1/* 2 * salinfo.c 3 * 4 * Creates entries in /proc/sal for various system features. 5 * 6 * Copyright (c) 2003, 2006 Silicon Graphics, Inc. All rights reserved. 7 * Copyright (c) 2003 Hewlett-Packard Co 8 * Bjorn Helgaas <bjorn.helgaas@hp.com> 9 * 10 * 10/30/2001 jbarnes@sgi.com copied much of Stephane's palinfo 11 * code to create this file 12 * Oct 23 2003 kaos@sgi.com 13 * Replace IPI with set_cpus_allowed() to read a record from the required cpu. 14 * Redesign salinfo log processing to separate interrupt and user space 15 * contexts. 16 * Cache the record across multi-block reads from user space. 17 * Support > 64 cpus. 18 * Delete module_exit and MOD_INC/DEC_COUNT, salinfo cannot be a module. 19 * 20 * Jan 28 2004 kaos@sgi.com 21 * Periodically check for outstanding MCA or INIT records. 22 * 23 * Dec 5 2004 kaos@sgi.com 24 * Standardize which records are cleared automatically. 25 * 26 * Aug 18 2005 kaos@sgi.com 27 * mca.c may not pass a buffer, a NULL buffer just indicates that a new 28 * record is available in SAL. 29 * Replace some NR_CPUS by cpus_online, for hotplug cpu. 30 * 31 * Jan 5 2006 kaos@sgi.com 32 * Handle hotplug cpus coming online. 33 * Handle hotplug cpus going offline while they still have outstanding records. 34 * Use the cpu_* macros consistently. 35 * Replace the counting semaphore with a mutex and a test if the cpumask is non-empty. 36 * Modify the locking to make the test for "work to do" an atomic operation. 37 */ 38 39#include <linux/capability.h> 40#include <linux/cpu.h> 41#include <linux/types.h> 42#include <linux/proc_fs.h> 43#include <linux/module.h> 44#include <linux/smp.h> 45#include <linux/timer.h> 46#include <linux/vmalloc.h> 47#include <linux/semaphore.h> 48 49#include <asm/sal.h> 50#include <asm/uaccess.h> 51 52MODULE_AUTHOR("Jesse Barnes <jbarnes@sgi.com>"); 53MODULE_DESCRIPTION("/proc interface to IA-64 SAL features"); 54MODULE_LICENSE("GPL"); 55 56static int salinfo_read(char *page, char **start, off_t off, int count, int *eof, void *data); 57 58typedef struct { 59 const char *name; /* name of the proc entry */ 60 unsigned long feature; /* feature bit */ 61 struct proc_dir_entry *entry; /* registered entry (removal) */ 62} salinfo_entry_t; 63 64/* 65 * List {name,feature} pairs for every entry in /proc/sal/<feature> 66 * that this module exports 67 */ 68static salinfo_entry_t salinfo_entries[]={ 69 { "bus_lock", IA64_SAL_PLATFORM_FEATURE_BUS_LOCK, }, 70 { "irq_redirection", IA64_SAL_PLATFORM_FEATURE_IRQ_REDIR_HINT, }, 71 { "ipi_redirection", IA64_SAL_PLATFORM_FEATURE_IPI_REDIR_HINT, }, 72 { "itc_drift", IA64_SAL_PLATFORM_FEATURE_ITC_DRIFT, }, 73}; 74 75#define NR_SALINFO_ENTRIES ARRAY_SIZE(salinfo_entries) 76 77static char *salinfo_log_name[] = { 78 "mca", 79 "init", 80 "cmc", 81 "cpe", 82}; 83 84static struct proc_dir_entry *salinfo_proc_entries[ 85 ARRAY_SIZE(salinfo_entries) + /* /proc/sal/bus_lock */ 86 ARRAY_SIZE(salinfo_log_name) + /* /proc/sal/{mca,...} */ 87 (2 * ARRAY_SIZE(salinfo_log_name)) + /* /proc/sal/mca/{event,data} */ 88 1]; /* /proc/sal */ 89 90/* Some records we get ourselves, some are accessed as saved data in buffers 91 * that are owned by mca.c. 92 */ 93struct salinfo_data_saved { 94 u8* buffer; 95 u64 size; 96 u64 id; 97 int cpu; 98}; 99 100/* State transitions. Actions are :- 101 * Write "read <cpunum>" to the data file. 102 * Write "clear <cpunum>" to the data file. 103 * Write "oemdata <cpunum> <offset> to the data file. 104 * Read from the data file. 105 * Close the data file. 106 * 107 * Start state is NO_DATA. 108 * 109 * NO_DATA 110 * write "read <cpunum>" -> NO_DATA or LOG_RECORD. 111 * write "clear <cpunum>" -> NO_DATA or LOG_RECORD. 112 * write "oemdata <cpunum> <offset> -> return -EINVAL. 113 * read data -> return EOF. 114 * close -> unchanged. Free record areas. 115 * 116 * LOG_RECORD 117 * write "read <cpunum>" -> NO_DATA or LOG_RECORD. 118 * write "clear <cpunum>" -> NO_DATA or LOG_RECORD. 119 * write "oemdata <cpunum> <offset> -> format the oem data, goto OEMDATA. 120 * read data -> return the INIT/MCA/CMC/CPE record. 121 * close -> unchanged. Keep record areas. 122 * 123 * OEMDATA 124 * write "read <cpunum>" -> NO_DATA or LOG_RECORD. 125 * write "clear <cpunum>" -> NO_DATA or LOG_RECORD. 126 * write "oemdata <cpunum> <offset> -> format the oem data, goto OEMDATA. 127 * read data -> return the formatted oemdata. 128 * close -> unchanged. Keep record areas. 129 * 130 * Closing the data file does not change the state. This allows shell scripts 131 * to manipulate salinfo data, each shell redirection opens the file, does one 132 * action then closes it again. The record areas are only freed at close when 133 * the state is NO_DATA. 134 */ 135enum salinfo_state { 136 STATE_NO_DATA, 137 STATE_LOG_RECORD, 138 STATE_OEMDATA, 139}; 140 141struct salinfo_data { 142 cpumask_t cpu_event; /* which cpus have outstanding events */ 143 struct semaphore mutex; 144 u8 *log_buffer; 145 u64 log_size; 146 u8 *oemdata; /* decoded oem data */ 147 u64 oemdata_size; 148 int open; /* single-open to prevent races */ 149 u8 type; 150 u8 saved_num; /* using a saved record? */ 151 enum salinfo_state state :8; /* processing state */ 152 u8 padding; 153 int cpu_check; /* next CPU to check */ 154 struct salinfo_data_saved data_saved[5];/* save last 5 records from mca.c, must be < 255 */ 155}; 156 157static struct salinfo_data salinfo_data[ARRAY_SIZE(salinfo_log_name)]; 158 159static DEFINE_SPINLOCK(data_lock); 160static DEFINE_SPINLOCK(data_saved_lock); 161 162/** salinfo_platform_oemdata - optional callback to decode oemdata from an error 163 * record. 164 * @sect_header: pointer to the start of the section to decode. 165 * @oemdata: returns vmalloc area containing the decoded output. 166 * @oemdata_size: returns length of decoded output (strlen). 167 * 168 * Description: If user space asks for oem data to be decoded by the kernel 169 * and/or prom and the platform has set salinfo_platform_oemdata to the address 170 * of a platform specific routine then call that routine. salinfo_platform_oemdata 171 * vmalloc's and formats its output area, returning the address of the text 172 * and its strlen. Returns 0 for success, -ve for error. The callback is 173 * invoked on the cpu that generated the error record. 174 */ 175int (*salinfo_platform_oemdata)(const u8 *sect_header, u8 **oemdata, u64 *oemdata_size); 176 177struct salinfo_platform_oemdata_parms { 178 const u8 *efi_guid; 179 u8 **oemdata; 180 u64 *oemdata_size; 181 int ret; 182}; 183 184/* Kick the mutex that tells user space that there is work to do. Instead of 185 * trying to track the state of the mutex across multiple cpus, in user 186 * context, interrupt context, non-maskable interrupt context and hotplug cpu, 187 * it is far easier just to grab the mutex if it is free then release it. 188 * 189 * This routine must be called with data_saved_lock held, to make the down/up 190 * operation atomic. 191 */ 192static void 193salinfo_work_to_do(struct salinfo_data *data) 194{ 195 (void)(down_trylock(&data->mutex) ?: 0); 196 up(&data->mutex); 197} 198 199static void 200salinfo_platform_oemdata_cpu(void *context) 201{ 202 struct salinfo_platform_oemdata_parms *parms = context; 203 parms->ret = salinfo_platform_oemdata(parms->efi_guid, parms->oemdata, parms->oemdata_size); 204} 205 206static void 207shift1_data_saved (struct salinfo_data *data, int shift) 208{ 209 memcpy(data->data_saved+shift, data->data_saved+shift+1, 210 (ARRAY_SIZE(data->data_saved) - (shift+1)) * sizeof(data->data_saved[0])); 211 memset(data->data_saved + ARRAY_SIZE(data->data_saved) - 1, 0, 212 sizeof(data->data_saved[0])); 213} 214 215/* This routine is invoked in interrupt context. Note: mca.c enables 216 * interrupts before calling this code for CMC/CPE. MCA and INIT events are 217 * not irq safe, do not call any routines that use spinlocks, they may deadlock. 218 * MCA and INIT records are recorded, a timer event will look for any 219 * outstanding events and wake up the user space code. 220 * 221 * The buffer passed from mca.c points to the output from ia64_log_get. This is 222 * a persistent buffer but its contents can change between the interrupt and 223 * when user space processes the record. Save the record id to identify 224 * changes. If the buffer is NULL then just update the bitmap. 225 */ 226void 227salinfo_log_wakeup(int type, u8 *buffer, u64 size, int irqsafe) 228{ 229 struct salinfo_data *data = salinfo_data + type; 230 struct salinfo_data_saved *data_saved; 231 unsigned long flags = 0; 232 int i; 233 int saved_size = ARRAY_SIZE(data->data_saved); 234 235 BUG_ON(type >= ARRAY_SIZE(salinfo_log_name)); 236 237 if (irqsafe) 238 spin_lock_irqsave(&data_saved_lock, flags); 239 if (buffer) { 240 for (i = 0, data_saved = data->data_saved; i < saved_size; ++i, ++data_saved) { 241 if (!data_saved->buffer) 242 break; 243 } 244 if (i == saved_size) { 245 if (!data->saved_num) { 246 shift1_data_saved(data, 0); 247 data_saved = data->data_saved + saved_size - 1; 248 } else 249 data_saved = NULL; 250 } 251 if (data_saved) { 252 data_saved->cpu = smp_processor_id(); 253 data_saved->id = ((sal_log_record_header_t *)buffer)->id; 254 data_saved->size = size; 255 data_saved->buffer = buffer; 256 } 257 } 258 cpu_set(smp_processor_id(), data->cpu_event); 259 if (irqsafe) { 260 salinfo_work_to_do(data); 261 spin_unlock_irqrestore(&data_saved_lock, flags); 262 } 263} 264 265/* Check for outstanding MCA/INIT records every minute (arbitrary) */ 266#define SALINFO_TIMER_DELAY (60*HZ) 267static struct timer_list salinfo_timer; 268extern void ia64_mlogbuf_dump(void); 269 270static void 271salinfo_timeout_check(struct salinfo_data *data) 272{ 273 unsigned long flags; 274 if (!data->open) 275 return; 276 if (!cpus_empty(data->cpu_event)) { 277 spin_lock_irqsave(&data_saved_lock, flags); 278 salinfo_work_to_do(data); 279 spin_unlock_irqrestore(&data_saved_lock, flags); 280 } 281} 282 283static void 284salinfo_timeout (unsigned long arg) 285{ 286 ia64_mlogbuf_dump(); 287 salinfo_timeout_check(salinfo_data + SAL_INFO_TYPE_MCA); 288 salinfo_timeout_check(salinfo_data + SAL_INFO_TYPE_INIT); 289 salinfo_timer.expires = jiffies + SALINFO_TIMER_DELAY; 290 add_timer(&salinfo_timer); 291} 292 293static int 294salinfo_event_open(struct inode *inode, struct file *file) 295{ 296 if (!capable(CAP_SYS_ADMIN)) 297 return -EPERM; 298 return 0; 299} 300 301static ssize_t 302salinfo_event_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos) 303{ 304 struct inode *inode = file->f_path.dentry->d_inode; 305 struct proc_dir_entry *entry = PDE(inode); 306 struct salinfo_data *data = entry->data; 307 char cmd[32]; 308 size_t size; 309 int i, n, cpu = -1; 310 311retry: 312 if (cpus_empty(data->cpu_event) && down_trylock(&data->mutex)) { 313 if (file->f_flags & O_NONBLOCK) 314 return -EAGAIN; 315 if (down_interruptible(&data->mutex)) 316 return -EINTR; 317 } 318 319 n = data->cpu_check; 320 for (i = 0; i < nr_cpu_ids; i++) { 321 if (cpu_isset(n, data->cpu_event)) { 322 if (!cpu_online(n)) { 323 cpu_clear(n, data->cpu_event); 324 continue; 325 } 326 cpu = n; 327 break; 328 } 329 if (++n == nr_cpu_ids) 330 n = 0; 331 } 332 333 if (cpu == -1) 334 goto retry; 335 336 ia64_mlogbuf_dump(); 337 338 /* for next read, start checking at next CPU */ 339 data->cpu_check = cpu; 340 if (++data->cpu_check == nr_cpu_ids) 341 data->cpu_check = 0; 342 343 snprintf(cmd, sizeof(cmd), "read %d\n", cpu); 344 345 size = strlen(cmd); 346 if (size > count) 347 size = count; 348 if (copy_to_user(buffer, cmd, size)) 349 return -EFAULT; 350 351 return size; 352} 353 354static const struct file_operations salinfo_event_fops = { 355 .open = salinfo_event_open, 356 .read = salinfo_event_read, 357}; 358 359static int 360salinfo_log_open(struct inode *inode, struct file *file) 361{ 362 struct proc_dir_entry *entry = PDE(inode); 363 struct salinfo_data *data = entry->data; 364 365 if (!capable(CAP_SYS_ADMIN)) 366 return -EPERM; 367 368 spin_lock(&data_lock); 369 if (data->open) { 370 spin_unlock(&data_lock); 371 return -EBUSY; 372 } 373 data->open = 1; 374 spin_unlock(&data_lock); 375 376 if (data->state == STATE_NO_DATA && 377 !(data->log_buffer = vmalloc(ia64_sal_get_state_info_size(data->type)))) { 378 data->open = 0; 379 return -ENOMEM; 380 } 381 382 return 0; 383} 384 385static int 386salinfo_log_release(struct inode *inode, struct file *file) 387{ 388 struct proc_dir_entry *entry = PDE(inode); 389 struct salinfo_data *data = entry->data; 390 391 if (data->state == STATE_NO_DATA) { 392 vfree(data->log_buffer); 393 vfree(data->oemdata); 394 data->log_buffer = NULL; 395 data->oemdata = NULL; 396 } 397 spin_lock(&data_lock); 398 data->open = 0; 399 spin_unlock(&data_lock); 400 return 0; 401} 402 403static void 404call_on_cpu(int cpu, void (*fn)(void *), void *arg) 405{ 406 cpumask_t save_cpus_allowed = current->cpus_allowed; 407 set_cpus_allowed_ptr(current, cpumask_of(cpu)); 408 (*fn)(arg); 409 set_cpus_allowed_ptr(current, &save_cpus_allowed); 410} 411 412static void 413salinfo_log_read_cpu(void *context) 414{ 415 struct salinfo_data *data = context; 416 sal_log_record_header_t *rh; 417 data->log_size = ia64_sal_get_state_info(data->type, (u64 *) data->log_buffer); 418 rh = (sal_log_record_header_t *)(data->log_buffer); 419 /* Clear corrected errors as they are read from SAL */ 420 if (rh->severity == sal_log_severity_corrected) 421 ia64_sal_clear_state_info(data->type); 422} 423 424static void 425salinfo_log_new_read(int cpu, struct salinfo_data *data) 426{ 427 struct salinfo_data_saved *data_saved; 428 unsigned long flags; 429 int i; 430 int saved_size = ARRAY_SIZE(data->data_saved); 431 432 data->saved_num = 0; 433 spin_lock_irqsave(&data_saved_lock, flags); 434retry: 435 for (i = 0, data_saved = data->data_saved; i < saved_size; ++i, ++data_saved) { 436 if (data_saved->buffer && data_saved->cpu == cpu) { 437 sal_log_record_header_t *rh = (sal_log_record_header_t *)(data_saved->buffer); 438 data->log_size = data_saved->size; 439 memcpy(data->log_buffer, rh, data->log_size); 440 barrier(); /* id check must not be moved */ 441 if (rh->id == data_saved->id) { 442 data->saved_num = i+1; 443 break; 444 } 445 /* saved record changed by mca.c since interrupt, discard it */ 446 shift1_data_saved(data, i); 447 goto retry; 448 } 449 } 450 spin_unlock_irqrestore(&data_saved_lock, flags); 451 452 if (!data->saved_num) 453 call_on_cpu(cpu, salinfo_log_read_cpu, data); 454 if (!data->log_size) { 455 data->state = STATE_NO_DATA; 456 cpu_clear(cpu, data->cpu_event); 457 } else { 458 data->state = STATE_LOG_RECORD; 459 } 460} 461 462static ssize_t 463salinfo_log_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos) 464{ 465 struct inode *inode = file->f_path.dentry->d_inode; 466 struct proc_dir_entry *entry = PDE(inode); 467 struct salinfo_data *data = entry->data; 468 u8 *buf; 469 u64 bufsize; 470 471 if (data->state == STATE_LOG_RECORD) { 472 buf = data->log_buffer; 473 bufsize = data->log_size; 474 } else if (data->state == STATE_OEMDATA) { 475 buf = data->oemdata; 476 bufsize = data->oemdata_size; 477 } else { 478 buf = NULL; 479 bufsize = 0; 480 } 481 return simple_read_from_buffer(buffer, count, ppos, buf, bufsize); 482} 483 484static void 485salinfo_log_clear_cpu(void *context) 486{ 487 struct salinfo_data *data = context; 488 ia64_sal_clear_state_info(data->type); 489} 490 491static int 492salinfo_log_clear(struct salinfo_data *data, int cpu) 493{ 494 sal_log_record_header_t *rh; 495 unsigned long flags; 496 spin_lock_irqsave(&data_saved_lock, flags); 497 data->state = STATE_NO_DATA; 498 if (!cpu_isset(cpu, data->cpu_event)) { 499 spin_unlock_irqrestore(&data_saved_lock, flags); 500 return 0; 501 } 502 cpu_clear(cpu, data->cpu_event); 503 if (data->saved_num) { 504 shift1_data_saved(data, data->saved_num - 1); 505 data->saved_num = 0; 506 } 507 spin_unlock_irqrestore(&data_saved_lock, flags); 508 rh = (sal_log_record_header_t *)(data->log_buffer); 509 /* Corrected errors have already been cleared from SAL */ 510 if (rh->severity != sal_log_severity_corrected) 511 call_on_cpu(cpu, salinfo_log_clear_cpu, data); 512 /* clearing a record may make a new record visible */ 513 salinfo_log_new_read(cpu, data); 514 if (data->state == STATE_LOG_RECORD) { 515 spin_lock_irqsave(&data_saved_lock, flags); 516 cpu_set(cpu, data->cpu_event); 517 salinfo_work_to_do(data); 518 spin_unlock_irqrestore(&data_saved_lock, flags); 519 } 520 return 0; 521} 522 523static ssize_t 524salinfo_log_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos) 525{ 526 struct inode *inode = file->f_path.dentry->d_inode; 527 struct proc_dir_entry *entry = PDE(inode); 528 struct salinfo_data *data = entry->data; 529 char cmd[32]; 530 size_t size; 531 u32 offset; 532 int cpu; 533 534 size = sizeof(cmd); 535 if (count < size) 536 size = count; 537 if (copy_from_user(cmd, buffer, size)) 538 return -EFAULT; 539 540 if (sscanf(cmd, "read %d", &cpu) == 1) { 541 salinfo_log_new_read(cpu, data); 542 } else if (sscanf(cmd, "clear %d", &cpu) == 1) { 543 int ret; 544 if ((ret = salinfo_log_clear(data, cpu))) 545 count = ret; 546 } else if (sscanf(cmd, "oemdata %d %d", &cpu, &offset) == 2) { 547 if (data->state != STATE_LOG_RECORD && data->state != STATE_OEMDATA) 548 return -EINVAL; 549 if (offset > data->log_size - sizeof(efi_guid_t)) 550 return -EINVAL; 551 data->state = STATE_OEMDATA; 552 if (salinfo_platform_oemdata) { 553 struct salinfo_platform_oemdata_parms parms = { 554 .efi_guid = data->log_buffer + offset, 555 .oemdata = &data->oemdata, 556 .oemdata_size = &data->oemdata_size 557 }; 558 call_on_cpu(cpu, salinfo_platform_oemdata_cpu, &parms); 559 if (parms.ret) 560 count = parms.ret; 561 } else 562 data->oemdata_size = 0; 563 } else 564 return -EINVAL; 565 566 return count; 567} 568 569static const struct file_operations salinfo_data_fops = { 570 .open = salinfo_log_open, 571 .release = salinfo_log_release, 572 .read = salinfo_log_read, 573 .write = salinfo_log_write, 574}; 575 576static int __cpuinit 577salinfo_cpu_callback(struct notifier_block *nb, unsigned long action, void *hcpu) 578{ 579 unsigned int i, cpu = (unsigned long)hcpu; 580 unsigned long flags; 581 struct salinfo_data *data; 582 switch (action) { 583 case CPU_ONLINE: 584 case CPU_ONLINE_FROZEN: 585 spin_lock_irqsave(&data_saved_lock, flags); 586 for (i = 0, data = salinfo_data; 587 i < ARRAY_SIZE(salinfo_data); 588 ++i, ++data) { 589 cpu_set(cpu, data->cpu_event); 590 salinfo_work_to_do(data); 591 } 592 spin_unlock_irqrestore(&data_saved_lock, flags); 593 break; 594 case CPU_DEAD: 595 case CPU_DEAD_FROZEN: 596 spin_lock_irqsave(&data_saved_lock, flags); 597 for (i = 0, data = salinfo_data; 598 i < ARRAY_SIZE(salinfo_data); 599 ++i, ++data) { 600 struct salinfo_data_saved *data_saved; 601 int j; 602 for (j = ARRAY_SIZE(data->data_saved) - 1, data_saved = data->data_saved + j; 603 j >= 0; 604 --j, --data_saved) { 605 if (data_saved->buffer && data_saved->cpu == cpu) { 606 shift1_data_saved(data, j); 607 } 608 } 609 cpu_clear(cpu, data->cpu_event); 610 } 611 spin_unlock_irqrestore(&data_saved_lock, flags); 612 break; 613 } 614 return NOTIFY_OK; 615} 616 617static struct notifier_block salinfo_cpu_notifier __cpuinitdata = 618{ 619 .notifier_call = salinfo_cpu_callback, 620 .priority = 0, 621}; 622 623static int __init 624salinfo_init(void) 625{ 626 struct proc_dir_entry *salinfo_dir; /* /proc/sal dir entry */ 627 struct proc_dir_entry **sdir = salinfo_proc_entries; /* keeps track of every entry */ 628 struct proc_dir_entry *dir, *entry; 629 struct salinfo_data *data; 630 int i, j; 631 632 salinfo_dir = proc_mkdir("sal", NULL); 633 if (!salinfo_dir) 634 return 0; 635 636 for (i=0; i < NR_SALINFO_ENTRIES; i++) { 637 /* pass the feature bit in question as misc data */ 638 *sdir++ = create_proc_read_entry (salinfo_entries[i].name, 0, salinfo_dir, 639 salinfo_read, (void *)salinfo_entries[i].feature); 640 } 641 642 for (i = 0; i < ARRAY_SIZE(salinfo_log_name); i++) { 643 data = salinfo_data + i; 644 data->type = i; 645 init_MUTEX(&data->mutex); 646 dir = proc_mkdir(salinfo_log_name[i], salinfo_dir); 647 if (!dir) 648 continue; 649 650 entry = proc_create_data("event", S_IRUSR, dir, 651 &salinfo_event_fops, data); 652 if (!entry) 653 continue; 654 *sdir++ = entry; 655 656 entry = proc_create_data("data", S_IRUSR | S_IWUSR, dir, 657 &salinfo_data_fops, data); 658 if (!entry) 659 continue; 660 *sdir++ = entry; 661 662 /* we missed any events before now */ 663 for_each_online_cpu(j) 664 cpu_set(j, data->cpu_event); 665 666 *sdir++ = dir; 667 } 668 669 *sdir++ = salinfo_dir; 670 671 init_timer(&salinfo_timer); 672 salinfo_timer.expires = jiffies + SALINFO_TIMER_DELAY; 673 salinfo_timer.function = &salinfo_timeout; 674 add_timer(&salinfo_timer); 675 676 register_hotcpu_notifier(&salinfo_cpu_notifier); 677 678 return 0; 679} 680 681/* 682 * 'data' contains an integer that corresponds to the feature we're 683 * testing 684 */ 685static int 686salinfo_read(char *page, char **start, off_t off, int count, int *eof, void *data) 687{ 688 int len = 0; 689 690 len = sprintf(page, (sal_platform_features & (unsigned long)data) ? "1\n" : "0\n"); 691 692 if (len <= off+count) *eof = 1; 693 694 *start = page + off; 695 len -= off; 696 697 if (len>count) len = count; 698 if (len<0) len = 0; 699 700 return len; 701} 702 703module_init(salinfo_init); 704