git.oblomov.eu Git - linux-2.6/blob - fs/proc/proc_misc.c

   1 /*
   2  *  linux/fs/proc/proc_misc.c
   3  *
   4  *  linux/fs/proc/array.c
   5  *  Copyright (C) 1992  by Linus Torvalds
   6  *  based on ideas by Darren Senn
   7  *
   8  *  This used to be the part of array.c. See the rest of history and credits
   9  *  there. I took this into a separate file and switched the thing to generic
  10  *  proc_file_inode_operations, leaving in array.c only per-process stuff.
  11  *  Inumbers allocation made dynamic (via create_proc_entry()).  AV, May 1999.
  12  *
  13  * Changes:
  14  * Fulton Green      :  Encapsulated position metric calculations.
  15  *                      <kernel@FultonGreen.com>
  16  */
  17
  18 #include <linux/types.h>
  19 #include <linux/errno.h>
  20 #include <linux/time.h>
  21 #include <linux/kernel.h>
  22 #include <linux/kernel_stat.h>
  23 #include <linux/tty.h>
  24 #include <linux/string.h>
  25 #include <linux/mman.h>
  26 #include <linux/proc_fs.h>
  27 #include <linux/ioport.h>
  28 #include <linux/config.h>
  29 #include <linux/mm.h>
  30 #include <linux/mmzone.h>
  31 #include <linux/pagemap.h>
  32 #include <linux/swap.h>
  33 #include <linux/slab.h>
  34 #include <linux/smp.h>
  35 #include <linux/signal.h>
  36 #include <linux/module.h>
  37 #include <linux/init.h>
  38 #include <linux/smp_lock.h>
  39 #include <linux/seq_file.h>
  40 #include <linux/times.h>
  41 #include <linux/profile.h>
  42 #include <linux/blkdev.h>
  43 #include <linux/hugetlb.h>
  44 #include <linux/jiffies.h>
  45 #include <linux/sysrq.h>
  46 #include <linux/vmalloc.h>
  47 #include <linux/crash_dump.h>
  48 #include <asm/uaccess.h>
  49 #include <asm/pgtable.h>
  50 #include <asm/io.h>
  51 #include <asm/tlb.h>
  52 #include <asm/div64.h>
  53 #include "internal.h"
  54
  55 #define LOAD_INT(x) ((x) >> FSHIFT)
  56 #define LOAD_FRAC(x) LOAD_INT(((x) & (FIXED_1-1)) * 100)
  57 /*
  58  * Warning: stuff below (imported functions) assumes that its output will fit
  59  * into one page. For some of those functions it may be wrong. Moreover, we
  60  * have a way to deal with that gracefully. Right now I used straightforward
  61  * wrappers, but this needs further analysis wrt potential overflows.
  62  */
  63 extern int get_hardware_list(char *);
  64 extern int get_stram_list(char *);
  65 extern int get_chrdev_list(char *);
  66 extern int get_filesystem_list(char *);
  67 extern int get_exec_domain_list(char *);
  68 extern int get_dma_list(char *);
  69 extern int get_locks_status (char *, char **, off_t, int);
  70
  71 static int proc_calc_metrics(char *page, char **start, off_t off,
  72                                  int count, int *eof, int len)
  73 {
  74         if (len <= off+count) *eof = 1;
  75         *start = page + off;
  76         len -= off;
  77         if (len>count) len = count;
  78         if (len<0) len = 0;
  79         return len;
  80 }
  81
  82 static int loadavg_read_proc(char *page, char **start, off_t off,
  83                                  int count, int *eof, void *data)
  84 {
  85         int a, b, c;
  86         int len;
  87
  88         a = avenrun[0] + (FIXED_1/200);
  89         b = avenrun[1] + (FIXED_1/200);
  90         c = avenrun[2] + (FIXED_1/200);
  91         len = sprintf(page,"%d.%02d %d.%02d %d.%02d %ld/%d %d\n",
  92                 LOAD_INT(a), LOAD_FRAC(a),
  93                 LOAD_INT(b), LOAD_FRAC(b),
  94                 LOAD_INT(c), LOAD_FRAC(c),
  95                 nr_running(), nr_threads, last_pid);
  96         return proc_calc_metrics(page, start, off, count, eof, len);
  97 }
  98
  99 static int uptime_read_proc(char *page, char **start, off_t off,
 100                                  int count, int *eof, void *data)
 101 {
 102         struct timespec uptime;
 103         struct timespec idle;
 104         int len;
 105         cputime_t idletime = cputime_add(init_task.utime, init_task.stime);
 106
 107         do_posix_clock_monotonic_gettime(&uptime);
 108         cputime_to_timespec(idletime, &idle);
 109         len = sprintf(page,"%lu.%02lu %lu.%02lu\n",
 110                         (unsigned long) uptime.tv_sec,
 111                         (uptime.tv_nsec / (NSEC_PER_SEC / 100)),
 112                         (unsigned long) idle.tv_sec,
 113                         (idle.tv_nsec / (NSEC_PER_SEC / 100)));
 114
 115         return proc_calc_metrics(page, start, off, count, eof, len);
 116 }
 117
 118 static int meminfo_read_proc(char *page, char **start, off_t off,
 119                                  int count, int *eof, void *data)
 120 {
 121         struct sysinfo i;
 122         int len;
 123         struct page_state ps;
 124         unsigned long inactive;
 125         unsigned long active;
 126         unsigned long free;
 127         unsigned long committed;
 128         unsigned long allowed;
 129         struct vmalloc_info vmi;
 130         long cached;
 131
 132         get_page_state(&ps);
 133         get_zone_counts(&active, &inactive, &free);
 134
 135 /*
 136  * display in kilobytes.
 137  */
 138 #define K(x) ((x) << (PAGE_SHIFT - 10))
 139         si_meminfo(&i);
 140         si_swapinfo(&i);
 141         committed = atomic_read(&vm_committed_space);
 142         allowed = ((totalram_pages - hugetlb_total_pages())
 143                 * sysctl_overcommit_ratio / 100) + total_swap_pages;
 144
 145         cached = get_page_cache_size() - total_swapcache_pages - i.bufferram;
 146         if (cached < 0)
 147                 cached = 0;
 148
 149         get_vmalloc_info(&vmi);
 150
 151         /*
 152          * Tagged format, for easy grepping and expansion.
 153          */
 154         len = sprintf(page,
 155                 "MemTotal:     %8lu kB\n"
 156                 "MemFree:      %8lu kB\n"
 157                 "Buffers:      %8lu kB\n"
 158                 "Cached:       %8lu kB\n"
 159                 "SwapCached:   %8lu kB\n"
 160                 "Active:       %8lu kB\n"
 161                 "Inactive:     %8lu kB\n"
 162                 "HighTotal:    %8lu kB\n"
 163                 "HighFree:     %8lu kB\n"
 164                 "LowTotal:     %8lu kB\n"
 165                 "LowFree:      %8lu kB\n"
 166                 "SwapTotal:    %8lu kB\n"
 167                 "SwapFree:     %8lu kB\n"
 168                 "Dirty:        %8lu kB\n"
 169                 "Writeback:    %8lu kB\n"
 170                 "Mapped:       %8lu kB\n"
 171                 "Slab:         %8lu kB\n"
 172                 "CommitLimit:  %8lu kB\n"
 173                 "Committed_AS: %8lu kB\n"
 174                 "PageTables:   %8lu kB\n"
 175                 "VmallocTotal: %8lu kB\n"
 176                 "VmallocUsed:  %8lu kB\n"
 177                 "VmallocChunk: %8lu kB\n",
 178                 K(i.totalram),
 179                 K(i.freeram),
 180                 K(i.bufferram),
 181                 K(cached),
 182                 K(total_swapcache_pages),
 183                 K(active),
 184                 K(inactive),
 185                 K(i.totalhigh),
 186                 K(i.freehigh),
 187                 K(i.totalram-i.totalhigh),
 188                 K(i.freeram-i.freehigh),
 189                 K(i.totalswap),
 190                 K(i.freeswap),
 191                 K(ps.nr_dirty),
 192                 K(ps.nr_writeback),
 193                 K(ps.nr_mapped),
 194                 K(ps.nr_slab),
 195                 K(allowed),
 196                 K(committed),
 197                 K(ps.nr_page_table_pages),
 198                 (unsigned long)VMALLOC_TOTAL >> 10,
 199                 vmi.used >> 10,
 200                 vmi.largest_chunk >> 10
 201                 );
 202
 203                 len += hugetlb_report_meminfo(page + len);
 204
 205         return proc_calc_metrics(page, start, off, count, eof, len);
 206 #undef K
 207 }
 208
 209 extern struct seq_operations fragmentation_op;
 210 static int fragmentation_open(struct inode *inode, struct file *file)
 211 {
 212         (void)inode;
 213         return seq_open(file, &fragmentation_op);
 214 }
 215
 216 static struct file_operations fragmentation_file_operations = {
 217         .open           = fragmentation_open,
 218         .read           = seq_read,
 219         .llseek         = seq_lseek,
 220         .release        = seq_release,
 221 };
 222
 223 extern struct seq_operations zoneinfo_op;
 224 static int zoneinfo_open(struct inode *inode, struct file *file)
 225 {
 226         return seq_open(file, &zoneinfo_op);
 227 }
 228
 229 static struct file_operations proc_zoneinfo_file_operations = {
 230         .open           = zoneinfo_open,
 231         .read           = seq_read,
 232         .llseek         = seq_lseek,
 233         .release        = seq_release,
 234 };
 235
 236 static int version_read_proc(char *page, char **start, off_t off,
 237                                  int count, int *eof, void *data)
 238 {
 239         int len;
 240
 241         strcpy(page, linux_banner);
 242         len = strlen(page);
 243         return proc_calc_metrics(page, start, off, count, eof, len);
 244 }
 245
 246 extern struct seq_operations cpuinfo_op;
 247 static int cpuinfo_open(struct inode *inode, struct file *file)
 248 {
 249         return seq_open(file, &cpuinfo_op);
 250 }
 251 static struct file_operations proc_cpuinfo_operations = {
 252         .open           = cpuinfo_open,
 253         .read           = seq_read,
 254         .llseek         = seq_lseek,
 255         .release        = seq_release,
 256 };
 257
 258 extern struct seq_operations vmstat_op;
 259 static int vmstat_open(struct inode *inode, struct file *file)
 260 {
 261         return seq_open(file, &vmstat_op);
 262 }
 263 static struct file_operations proc_vmstat_file_operations = {
 264         .open           = vmstat_open,
 265         .read           = seq_read,
 266         .llseek         = seq_lseek,
 267         .release        = seq_release,
 268 };
 269
 270 #ifdef CONFIG_PROC_HARDWARE
 271 static int hardware_read_proc(char *page, char **start, off_t off,
 272                                  int count, int *eof, void *data)
 273 {
 274         int len = get_hardware_list(page);
 275         return proc_calc_metrics(page, start, off, count, eof, len);
 276 }
 277 #endif
 278
 279 #ifdef CONFIG_STRAM_PROC
 280 static int stram_read_proc(char *page, char **start, off_t off,
 281                                  int count, int *eof, void *data)
 282 {
 283         int len = get_stram_list(page);
 284         return proc_calc_metrics(page, start, off, count, eof, len);
 285 }
 286 #endif
 287
 288 extern struct seq_operations partitions_op;
 289 static int partitions_open(struct inode *inode, struct file *file)
 290 {
 291         return seq_open(file, &partitions_op);
 292 }
 293 static struct file_operations proc_partitions_operations = {
 294         .open           = partitions_open,
 295         .read           = seq_read,
 296         .llseek         = seq_lseek,
 297         .release        = seq_release,
 298 };
 299
 300 extern struct seq_operations diskstats_op;
 301 static int diskstats_open(struct inode *inode, struct file *file)
 302 {
 303         return seq_open(file, &diskstats_op);
 304 }
 305 static struct file_operations proc_diskstats_operations = {
 306         .open           = diskstats_open,
 307         .read           = seq_read,
 308         .llseek         = seq_lseek,
 309         .release        = seq_release,
 310 };
 311
 312 #ifdef CONFIG_MODULES
 313 extern struct seq_operations modules_op;
 314 static int modules_open(struct inode *inode, struct file *file)
 315 {
 316         return seq_open(file, &modules_op);
 317 }
 318 static struct file_operations proc_modules_operations = {
 319         .open           = modules_open,
 320         .read           = seq_read,
 321         .llseek         = seq_lseek,
 322         .release        = seq_release,
 323 };
 324 #endif
 325
 326 #ifdef CONFIG_SLAB
 327 extern struct seq_operations slabinfo_op;
 328 extern ssize_t slabinfo_write(struct file *, const char __user *, size_t, loff_t *);
 329 static int slabinfo_open(struct inode *inode, struct file *file)
 330 {
 331         return seq_open(file, &slabinfo_op);
 332 }
 333 static struct file_operations proc_slabinfo_operations = {
 334         .open           = slabinfo_open,
 335         .read           = seq_read,
 336         .write          = slabinfo_write,
 337         .llseek         = seq_lseek,
 338         .release        = seq_release,
 339 };
 340 #endif
 341
 342 static int show_stat(struct seq_file *p, void *v)
 343 {
 344         int i;
 345         unsigned long jif;
 346         cputime64_t user, nice, system, idle, iowait, irq, softirq, steal;
 347         u64 sum = 0;
 348
 349         user = nice = system = idle = iowait =
 350                 irq = softirq = steal = cputime64_zero;
 351         jif = - wall_to_monotonic.tv_sec;
 352         if (wall_to_monotonic.tv_nsec)
 353                 --jif;
 354
 355         for_each_cpu(i) {
 356                 int j;
 357
 358                 user = cputime64_add(user, kstat_cpu(i).cpustat.user);
 359                 nice = cputime64_add(nice, kstat_cpu(i).cpustat.nice);
 360                 system = cputime64_add(system, kstat_cpu(i).cpustat.system);
 361                 idle = cputime64_add(idle, kstat_cpu(i).cpustat.idle);
 362                 iowait = cputime64_add(iowait, kstat_cpu(i).cpustat.iowait);
 363                 irq = cputime64_add(irq, kstat_cpu(i).cpustat.irq);
 364                 softirq = cputime64_add(softirq, kstat_cpu(i).cpustat.softirq);
 365                 steal = cputime64_add(steal, kstat_cpu(i).cpustat.steal);
 366                 for (j = 0 ; j < NR_IRQS ; j++)
 367                         sum += kstat_cpu(i).irqs[j];
 368         }
 369
 370         seq_printf(p, "cpu  %llu %llu %llu %llu %llu %llu %llu %llu\n",
 371                 (unsigned long long)cputime64_to_clock_t(user),
 372                 (unsigned long long)cputime64_to_clock_t(nice),
 373                 (unsigned long long)cputime64_to_clock_t(system),
 374                 (unsigned long long)cputime64_to_clock_t(idle),
 375                 (unsigned long long)cputime64_to_clock_t(iowait),
 376                 (unsigned long long)cputime64_to_clock_t(irq),
 377                 (unsigned long long)cputime64_to_clock_t(softirq),
 378                 (unsigned long long)cputime64_to_clock_t(steal));
 379         for_each_online_cpu(i) {
 380
 381                 /* Copy values here to work around gcc-2.95.3, gcc-2.96 */
 382                 user = kstat_cpu(i).cpustat.user;
 383                 nice = kstat_cpu(i).cpustat.nice;
 384                 system = kstat_cpu(i).cpustat.system;
 385                 idle = kstat_cpu(i).cpustat.idle;
 386                 iowait = kstat_cpu(i).cpustat.iowait;
 387                 irq = kstat_cpu(i).cpustat.irq;
 388                 softirq = kstat_cpu(i).cpustat.softirq;
 389                 steal = kstat_cpu(i).cpustat.steal;
 390                 seq_printf(p, "cpu%d %llu %llu %llu %llu %llu %llu %llu %llu\n",
 391                         i,
 392                         (unsigned long long)cputime64_to_clock_t(user),
 393                         (unsigned long long)cputime64_to_clock_t(nice),
 394                         (unsigned long long)cputime64_to_clock_t(system),
 395                         (unsigned long long)cputime64_to_clock_t(idle),
 396                         (unsigned long long)cputime64_to_clock_t(iowait),
 397                         (unsigned long long)cputime64_to_clock_t(irq),
 398                         (unsigned long long)cputime64_to_clock_t(softirq),
 399                         (unsigned long long)cputime64_to_clock_t(steal));
 400         }
 401         seq_printf(p, "intr %llu", (unsigned long long)sum);
 402
 403 #if !defined(CONFIG_PPC64) && !defined(CONFIG_ALPHA)
 404         for (i = 0; i < NR_IRQS; i++)
 405                 seq_printf(p, " %u", kstat_irqs(i));
 406 #endif
 407
 408         seq_printf(p,
 409                 "\nctxt %llu\n"
 410                 "btime %lu\n"
 411                 "processes %lu\n"
 412                 "procs_running %lu\n"
 413                 "procs_blocked %lu\n",
 414                 nr_context_switches(),
 415                 (unsigned long)jif,
 416                 total_forks,
 417                 nr_running(),
 418                 nr_iowait());
 419
 420         return 0;
 421 }
 422
 423 static int stat_open(struct inode *inode, struct file *file)
 424 {
 425         unsigned size = 4096 * (1 + num_possible_cpus() / 32);
 426         char *buf;
 427         struct seq_file *m;
 428         int res;
 429
 430         /* don't ask for more than the kmalloc() max size, currently 128 KB */
 431         if (size > 128 * 1024)
 432                 size = 128 * 1024;
 433         buf = kmalloc(size, GFP_KERNEL);
 434         if (!buf)
 435                 return -ENOMEM;
 436
 437         res = single_open(file, show_stat, NULL);
 438         if (!res) {
 439                 m = file->private_data;
 440                 m->buf = buf;
 441                 m->size = size;
 442         } else
 443                 kfree(buf);
 444         return res;
 445 }
 446 static struct file_operations proc_stat_operations = {
 447         .open           = stat_open,
 448         .read           = seq_read,
 449         .llseek         = seq_lseek,
 450         .release        = single_release,
 451 };
 452
 453 static int devices_read_proc(char *page, char **start, off_t off,
 454                                  int count, int *eof, void *data)
 455 {
 456         int len = get_chrdev_list(page);
 457         len += get_blkdev_list(page+len, len);
 458         return proc_calc_metrics(page, start, off, count, eof, len);
 459 }
 460
 461 /*
 462  * /proc/interrupts
 463  */
 464 static void *int_seq_start(struct seq_file *f, loff_t *pos)
 465 {
 466         return (*pos <= NR_IRQS) ? pos : NULL;
 467 }
 468
 469 static void *int_seq_next(struct seq_file *f, void *v, loff_t *pos)
 470 {
 471         (*pos)++;
 472         if (*pos > NR_IRQS)
 473                 return NULL;
 474         return pos;
 475 }
 476
 477 static void int_seq_stop(struct seq_file *f, void *v)
 478 {
 479         /* Nothing to do */
 480 }
 481
 482
 483 extern int show_interrupts(struct seq_file *f, void *v); /* In arch code */
 484 static struct seq_operations int_seq_ops = {
 485         .start = int_seq_start,
 486         .next  = int_seq_next,
 487         .stop  = int_seq_stop,
 488         .show  = show_interrupts
 489 };
 490
 491 static int interrupts_open(struct inode *inode, struct file *filp)
 492 {
 493         return seq_open(filp, &int_seq_ops);
 494 }
 495
 496 static struct file_operations proc_interrupts_operations = {
 497         .open           = interrupts_open,
 498         .read           = seq_read,
 499         .llseek         = seq_lseek,
 500         .release        = seq_release,
 501 };
 502
 503 static int filesystems_read_proc(char *page, char **start, off_t off,
 504                                  int count, int *eof, void *data)
 505 {
 506         int len = get_filesystem_list(page);
 507         return proc_calc_metrics(page, start, off, count, eof, len);
 508 }
 509
 510 static int cmdline_read_proc(char *page, char **start, off_t off,
 511                                  int count, int *eof, void *data)
 512 {
 513         int len;
 514
 515         len = sprintf(page, "%s\n", saved_command_line);
 516         return proc_calc_metrics(page, start, off, count, eof, len);
 517 }
 518
 519 static int locks_read_proc(char *page, char **start, off_t off,
 520                                  int count, int *eof, void *data)
 521 {
 522         int len = get_locks_status(page, start, off, count);
 523
 524         if (len < count)
 525                 *eof = 1;
 526         return len;
 527 }
 528
 529 static int execdomains_read_proc(char *page, char **start, off_t off,
 530                                  int count, int *eof, void *data)
 531 {
 532         int len = get_exec_domain_list(page);
 533         return proc_calc_metrics(page, start, off, count, eof, len);
 534 }
 535
 536 #ifdef CONFIG_MAGIC_SYSRQ
 537 /*
 538  * writing 'C' to /proc/sysrq-trigger is like sysrq-C
 539  */
 540 static ssize_t write_sysrq_trigger(struct file *file, const char __user *buf,
 541                                    size_t count, loff_t *ppos)
 542 {
 543         if (count) {
 544                 char c;
 545
 546                 if (get_user(c, buf))
 547                         return -EFAULT;
 548                 __handle_sysrq(c, NULL, NULL, 0);
 549         }
 550         return count;
 551 }
 552
 553 static struct file_operations proc_sysrq_trigger_operations = {
 554         .write          = write_sysrq_trigger,
 555 };
 556 #endif
 557
 558 struct proc_dir_entry *proc_root_kcore;
 559
 560 void create_seq_entry(char *name, mode_t mode, struct file_operations *f)
 561 {
 562         struct proc_dir_entry *entry;
 563         entry = create_proc_entry(name, mode, NULL);
 564         if (entry)
 565                 entry->proc_fops = f;
 566 }
 567
 568 void __init proc_misc_init(void)
 569 {
 570         struct proc_dir_entry *entry;
 571         static struct {
 572                 char *name;
 573                 int (*read_proc)(char*,char**,off_t,int,int*,void*);
 574         } *p, simple_ones[] = {
 575                 {"loadavg",     loadavg_read_proc},
 576                 {"uptime",      uptime_read_proc},
 577                 {"meminfo",     meminfo_read_proc},
 578                 {"version",     version_read_proc},
 579 #ifdef CONFIG_PROC_HARDWARE
 580                 {"hardware",    hardware_read_proc},
 581 #endif
 582 #ifdef CONFIG_STRAM_PROC
 583                 {"stram",       stram_read_proc},
 584 #endif
 585                 {"devices",     devices_read_proc},
 586                 {"filesystems", filesystems_read_proc},
 587                 {"cmdline",     cmdline_read_proc},
 588                 {"locks",       locks_read_proc},
 589                 {"execdomains", execdomains_read_proc},
 590                 {NULL,}
 591         };
 592         for (p = simple_ones; p->name; p++)
 593                 create_proc_read_entry(p->name, 0, NULL, p->read_proc, NULL);
 594
 595         proc_symlink("mounts", NULL, "self/mounts");
 596
 597         /* And now for trickier ones */
 598         entry = create_proc_entry("kmsg", S_IRUSR, &proc_root);
 599         if (entry)
 600                 entry->proc_fops = &proc_kmsg_operations;
 601         create_seq_entry("cpuinfo", 0, &proc_cpuinfo_operations);
 602         create_seq_entry("partitions", 0, &proc_partitions_operations);
 603         create_seq_entry("stat", 0, &proc_stat_operations);
 604         create_seq_entry("interrupts", 0, &proc_interrupts_operations);
 605 #ifdef CONFIG_SLAB
 606         create_seq_entry("slabinfo",S_IWUSR|S_IRUGO,&proc_slabinfo_operations);
 607 #endif
 608         create_seq_entry("buddyinfo",S_IRUGO, &fragmentation_file_operations);
 609         create_seq_entry("vmstat",S_IRUGO, &proc_vmstat_file_operations);
 610         create_seq_entry("zoneinfo",S_IRUGO, &proc_zoneinfo_file_operations);
 611         create_seq_entry("diskstats", 0, &proc_diskstats_operations);
 612 #ifdef CONFIG_MODULES
 613         create_seq_entry("modules", 0, &proc_modules_operations);
 614 #endif
 615 #ifdef CONFIG_SCHEDSTATS
 616         create_seq_entry("schedstat", 0, &proc_schedstat_operations);
 617 #endif
 618 #ifdef CONFIG_PROC_KCORE
 619         proc_root_kcore = create_proc_entry("kcore", S_IRUSR, NULL);
 620         if (proc_root_kcore) {
 621                 proc_root_kcore->proc_fops = &proc_kcore_operations;
 622                 proc_root_kcore->size =
 623                                 (size_t)high_memory - PAGE_OFFSET + PAGE_SIZE;
 624         }
 625 #endif
 626 #ifdef CONFIG_PROC_VMCORE
 627         proc_vmcore = create_proc_entry("vmcore", S_IRUSR, NULL);
 628         if (proc_vmcore)
 629                 proc_vmcore->proc_fops = &proc_vmcore_operations;
 630 #endif
 631 #ifdef CONFIG_MAGIC_SYSRQ
 632         entry = create_proc_entry("sysrq-trigger", S_IWUSR, NULL);
 633         if (entry)
 634                 entry->proc_fops = &proc_sysrq_trigger_operations;
 635 #endif
 636 }