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 <asm/uaccess.h>
  48 #include <asm/pgtable.h>
  49 #include <asm/io.h>
  50 #include <asm/tlb.h>
  51 #include <asm/div64.h>
  52 #include "internal.h"
  53
  54 #define LOAD_INT(x) ((x) >> FSHIFT)
  55 #define LOAD_FRAC(x) LOAD_INT(((x) & (FIXED_1-1)) * 100)
  56 /*
  57  * Warning: stuff below (imported functions) assumes that its output will fit
  58  * into one page. For some of those functions it may be wrong. Moreover, we
  59  * have a way to deal with that gracefully. Right now I used straightforward
  60  * wrappers, but this needs further analysis wrt potential overflows.
  61  */
  62 extern int get_hardware_list(char *);
  63 extern int get_stram_list(char *);
  64 extern int get_chrdev_list(char *);
  65 extern int get_filesystem_list(char *);
  66 extern int get_exec_domain_list(char *);
  67 extern int get_dma_list(char *);
  68 extern int get_locks_status (char *, char **, off_t, int);
  69
  70 static int proc_calc_metrics(char *page, char **start, off_t off,
  71                                  int count, int *eof, int len)
  72 {
  73         if (len <= off+count) *eof = 1;
  74         *start = page + off;
  75         len -= off;
  76         if (len>count) len = count;
  77         if (len<0) len = 0;
  78         return len;
  79 }
  80
  81 static int loadavg_read_proc(char *page, char **start, off_t off,
  82                                  int count, int *eof, void *data)
  83 {
  84         int a, b, c;
  85         int len;
  86
  87         a = avenrun[0] + (FIXED_1/200);
  88         b = avenrun[1] + (FIXED_1/200);
  89         c = avenrun[2] + (FIXED_1/200);
  90         len = sprintf(page,"%d.%02d %d.%02d %d.%02d %ld/%d %d\n",
  91                 LOAD_INT(a), LOAD_FRAC(a),
  92                 LOAD_INT(b), LOAD_FRAC(b),
  93                 LOAD_INT(c), LOAD_FRAC(c),
  94                 nr_running(), nr_threads, last_pid);
  95         return proc_calc_metrics(page, start, off, count, eof, len);
  96 }
  97
  98 static int uptime_read_proc(char *page, char **start, off_t off,
  99                                  int count, int *eof, void *data)
 100 {
 101         struct timespec uptime;
 102         struct timespec idle;
 103         int len;
 104         cputime_t idletime = cputime_add(init_task.utime, init_task.stime);
 105
 106         do_posix_clock_monotonic_gettime(&uptime);
 107         cputime_to_timespec(idletime, &idle);
 108         len = sprintf(page,"%lu.%02lu %lu.%02lu\n",
 109                         (unsigned long) uptime.tv_sec,
 110                         (uptime.tv_nsec / (NSEC_PER_SEC / 100)),
 111                         (unsigned long) idle.tv_sec,
 112                         (idle.tv_nsec / (NSEC_PER_SEC / 100)));
 113
 114         return proc_calc_metrics(page, start, off, count, eof, len);
 115 }
 116
 117 static int meminfo_read_proc(char *page, char **start, off_t off,
 118                                  int count, int *eof, void *data)
 119 {
 120         struct sysinfo i;
 121         int len;
 122         struct page_state ps;
 123         unsigned long inactive;
 124         unsigned long active;
 125         unsigned long free;
 126         unsigned long committed;
 127         unsigned long allowed;
 128         struct vmalloc_info vmi;
 129         long cached;
 130
 131         get_page_state(&ps);
 132         get_zone_counts(&active, &inactive, &free);
 133
 134 /*
 135  * display in kilobytes.
 136  */
 137 #define K(x) ((x) << (PAGE_SHIFT - 10))
 138         si_meminfo(&i);
 139         si_swapinfo(&i);
 140         committed = atomic_read(&vm_committed_space);
 141         allowed = ((totalram_pages - hugetlb_total_pages())
 142                 * sysctl_overcommit_ratio / 100) + total_swap_pages;
 143
 144         cached = get_page_cache_size() - total_swapcache_pages - i.bufferram;
 145         if (cached < 0)
 146                 cached = 0;
 147
 148         get_vmalloc_info(&vmi);
 149
 150         /*
 151          * Tagged format, for easy grepping and expansion.
 152          */
 153         len = sprintf(page,
 154                 "MemTotal:     %8lu kB\n"
 155                 "MemFree:      %8lu kB\n"
 156                 "Buffers:      %8lu kB\n"
 157                 "Cached:       %8lu kB\n"
 158                 "SwapCached:   %8lu kB\n"
 159                 "Active:       %8lu kB\n"
 160                 "Inactive:     %8lu kB\n"
 161                 "HighTotal:    %8lu kB\n"
 162                 "HighFree:     %8lu kB\n"
 163                 "LowTotal:     %8lu kB\n"
 164                 "LowFree:      %8lu kB\n"
 165                 "SwapTotal:    %8lu kB\n"
 166                 "SwapFree:     %8lu kB\n"
 167                 "Dirty:        %8lu kB\n"
 168                 "Writeback:    %8lu kB\n"
 169                 "Mapped:       %8lu kB\n"
 170                 "Slab:         %8lu kB\n"
 171                 "CommitLimit:  %8lu kB\n"
 172                 "Committed_AS: %8lu kB\n"
 173                 "PageTables:   %8lu kB\n"
 174                 "VmallocTotal: %8lu kB\n"
 175                 "VmallocUsed:  %8lu kB\n"
 176                 "VmallocChunk: %8lu kB\n",
 177                 K(i.totalram),
 178                 K(i.freeram),
 179                 K(i.bufferram),
 180                 K(cached),
 181                 K(total_swapcache_pages),
 182                 K(active),
 183                 K(inactive),
 184                 K(i.totalhigh),
 185                 K(i.freehigh),
 186                 K(i.totalram-i.totalhigh),
 187                 K(i.freeram-i.freehigh),
 188                 K(i.totalswap),
 189                 K(i.freeswap),
 190                 K(ps.nr_dirty),
 191                 K(ps.nr_writeback),
 192                 K(ps.nr_mapped),
 193                 K(ps.nr_slab),
 194                 K(allowed),
 195                 K(committed),
 196                 K(ps.nr_page_table_pages),
 197                 (unsigned long)VMALLOC_TOTAL >> 10,
 198                 vmi.used >> 10,
 199                 vmi.largest_chunk >> 10
 200                 );
 201
 202                 len += hugetlb_report_meminfo(page + len);
 203
 204         return proc_calc_metrics(page, start, off, count, eof, len);
 205 #undef K
 206 }
 207
 208 extern struct seq_operations fragmentation_op;
 209 static int fragmentation_open(struct inode *inode, struct file *file)
 210 {
 211         (void)inode;
 212         return seq_open(file, &fragmentation_op);
 213 }
 214
 215 static struct file_operations fragmentation_file_operations = {
 216         .open           = fragmentation_open,
 217         .read           = seq_read,
 218         .llseek         = seq_lseek,
 219         .release        = seq_release,
 220 };
 221
 222 extern struct seq_operations zoneinfo_op;
 223 static int zoneinfo_open(struct inode *inode, struct file *file)
 224 {
 225         return seq_open(file, &zoneinfo_op);
 226 }
 227
 228 static struct file_operations proc_zoneinfo_file_operations = {
 229         .open           = zoneinfo_open,
 230         .read           = seq_read,
 231         .llseek         = seq_lseek,
 232         .release        = seq_release,
 233 };
 234
 235 static int version_read_proc(char *page, char **start, off_t off,
 236                                  int count, int *eof, void *data)
 237 {
 238         int len;
 239
 240         strcpy(page, linux_banner);
 241         len = strlen(page);
 242         return proc_calc_metrics(page, start, off, count, eof, len);
 243 }
 244
 245 extern struct seq_operations cpuinfo_op;
 246 static int cpuinfo_open(struct inode *inode, struct file *file)
 247 {
 248         return seq_open(file, &cpuinfo_op);
 249 }
 250 static struct file_operations proc_cpuinfo_operations = {
 251         .open           = cpuinfo_open,
 252         .read           = seq_read,
 253         .llseek         = seq_lseek,
 254         .release        = seq_release,
 255 };
 256
 257 extern struct seq_operations vmstat_op;
 258 static int vmstat_open(struct inode *inode, struct file *file)
 259 {
 260         return seq_open(file, &vmstat_op);
 261 }
 262 static struct file_operations proc_vmstat_file_operations = {
 263         .open           = vmstat_open,
 264         .read           = seq_read,
 265         .llseek         = seq_lseek,
 266         .release        = seq_release,
 267 };
 268
 269 #ifdef CONFIG_PROC_HARDWARE
 270 static int hardware_read_proc(char *page, char **start, off_t off,
 271                                  int count, int *eof, void *data)
 272 {
 273         int len = get_hardware_list(page);
 274         return proc_calc_metrics(page, start, off, count, eof, len);
 275 }
 276 #endif
 277
 278 #ifdef CONFIG_STRAM_PROC
 279 static int stram_read_proc(char *page, char **start, off_t off,
 280                                  int count, int *eof, void *data)
 281 {
 282         int len = get_stram_list(page);
 283         return proc_calc_metrics(page, start, off, count, eof, len);
 284 }
 285 #endif
 286
 287 extern struct seq_operations partitions_op;
 288 static int partitions_open(struct inode *inode, struct file *file)
 289 {
 290         return seq_open(file, &partitions_op);
 291 }
 292 static struct file_operations proc_partitions_operations = {
 293         .open           = partitions_open,
 294         .read           = seq_read,
 295         .llseek         = seq_lseek,
 296         .release        = seq_release,
 297 };
 298
 299 extern struct seq_operations diskstats_op;
 300 static int diskstats_open(struct inode *inode, struct file *file)
 301 {
 302         return seq_open(file, &diskstats_op);
 303 }
 304 static struct file_operations proc_diskstats_operations = {
 305         .open           = diskstats_open,
 306         .read           = seq_read,
 307         .llseek         = seq_lseek,
 308         .release        = seq_release,
 309 };
 310
 311 #ifdef CONFIG_MODULES
 312 extern struct seq_operations modules_op;
 313 static int modules_open(struct inode *inode, struct file *file)
 314 {
 315         return seq_open(file, &modules_op);
 316 }
 317 static struct file_operations proc_modules_operations = {
 318         .open           = modules_open,
 319         .read           = seq_read,
 320         .llseek         = seq_lseek,
 321         .release        = seq_release,
 322 };
 323 #endif
 324
 325 extern struct seq_operations slabinfo_op;
 326 extern ssize_t slabinfo_write(struct file *, const char __user *, size_t, loff_t *);
 327 static int slabinfo_open(struct inode *inode, struct file *file)
 328 {
 329         return seq_open(file, &slabinfo_op);
 330 }
 331 static struct file_operations proc_slabinfo_operations = {
 332         .open           = slabinfo_open,
 333         .read           = seq_read,
 334         .write          = slabinfo_write,
 335         .llseek         = seq_lseek,
 336         .release        = seq_release,
 337 };
 338
 339 static int show_stat(struct seq_file *p, void *v)
 340 {
 341         int i;
 342         unsigned long jif;
 343         cputime64_t user, nice, system, idle, iowait, irq, softirq, steal;
 344         u64 sum = 0;
 345
 346         user = nice = system = idle = iowait =
 347                 irq = softirq = steal = cputime64_zero;
 348         jif = - wall_to_monotonic.tv_sec;
 349         if (wall_to_monotonic.tv_nsec)
 350                 --jif;
 351
 352         for_each_cpu(i) {
 353                 int j;
 354
 355                 user = cputime64_add(user, kstat_cpu(i).cpustat.user);
 356                 nice = cputime64_add(nice, kstat_cpu(i).cpustat.nice);
 357                 system = cputime64_add(system, kstat_cpu(i).cpustat.system);
 358                 idle = cputime64_add(idle, kstat_cpu(i).cpustat.idle);
 359                 iowait = cputime64_add(iowait, kstat_cpu(i).cpustat.iowait);
 360                 irq = cputime64_add(irq, kstat_cpu(i).cpustat.irq);
 361                 softirq = cputime64_add(softirq, kstat_cpu(i).cpustat.softirq);
 362                 steal = cputime64_add(steal, kstat_cpu(i).cpustat.steal);
 363                 for (j = 0 ; j < NR_IRQS ; j++)
 364                         sum += kstat_cpu(i).irqs[j];
 365         }
 366
 367         seq_printf(p, "cpu  %llu %llu %llu %llu %llu %llu %llu %llu\n",
 368                 (unsigned long long)cputime64_to_clock_t(user),
 369                 (unsigned long long)cputime64_to_clock_t(nice),
 370                 (unsigned long long)cputime64_to_clock_t(system),
 371                 (unsigned long long)cputime64_to_clock_t(idle),
 372                 (unsigned long long)cputime64_to_clock_t(iowait),
 373                 (unsigned long long)cputime64_to_clock_t(irq),
 374                 (unsigned long long)cputime64_to_clock_t(softirq),
 375                 (unsigned long long)cputime64_to_clock_t(steal));
 376         for_each_online_cpu(i) {
 377
 378                 /* Copy values here to work around gcc-2.95.3, gcc-2.96 */
 379                 user = kstat_cpu(i).cpustat.user;
 380                 nice = kstat_cpu(i).cpustat.nice;
 381                 system = kstat_cpu(i).cpustat.system;
 382                 idle = kstat_cpu(i).cpustat.idle;
 383                 iowait = kstat_cpu(i).cpustat.iowait;
 384                 irq = kstat_cpu(i).cpustat.irq;
 385                 softirq = kstat_cpu(i).cpustat.softirq;
 386                 steal = kstat_cpu(i).cpustat.steal;
 387                 seq_printf(p, "cpu%d %llu %llu %llu %llu %llu %llu %llu %llu\n",
 388                         i,
 389                         (unsigned long long)cputime64_to_clock_t(user),
 390                         (unsigned long long)cputime64_to_clock_t(nice),
 391                         (unsigned long long)cputime64_to_clock_t(system),
 392                         (unsigned long long)cputime64_to_clock_t(idle),
 393                         (unsigned long long)cputime64_to_clock_t(iowait),
 394                         (unsigned long long)cputime64_to_clock_t(irq),
 395                         (unsigned long long)cputime64_to_clock_t(softirq),
 396                         (unsigned long long)cputime64_to_clock_t(steal));
 397         }
 398         seq_printf(p, "intr %llu", (unsigned long long)sum);
 399
 400 #if !defined(CONFIG_PPC64) && !defined(CONFIG_ALPHA)
 401         for (i = 0; i < NR_IRQS; i++)
 402                 seq_printf(p, " %u", kstat_irqs(i));
 403 #endif
 404
 405         seq_printf(p,
 406                 "\nctxt %llu\n"
 407                 "btime %lu\n"
 408                 "processes %lu\n"
 409                 "procs_running %lu\n"
 410                 "procs_blocked %lu\n",
 411                 nr_context_switches(),
 412                 (unsigned long)jif,
 413                 total_forks,
 414                 nr_running(),
 415                 nr_iowait());
 416
 417         return 0;
 418 }
 419
 420 static int stat_open(struct inode *inode, struct file *file)
 421 {
 422         unsigned size = 4096 * (1 + num_possible_cpus() / 32);
 423         char *buf;
 424         struct seq_file *m;
 425         int res;
 426
 427         /* don't ask for more than the kmalloc() max size, currently 128 KB */
 428         if (size > 128 * 1024)
 429                 size = 128 * 1024;
 430         buf = kmalloc(size, GFP_KERNEL);
 431         if (!buf)
 432                 return -ENOMEM;
 433
 434         res = single_open(file, show_stat, NULL);
 435         if (!res) {
 436                 m = file->private_data;
 437                 m->buf = buf;
 438                 m->size = size;
 439         } else
 440                 kfree(buf);
 441         return res;
 442 }
 443 static struct file_operations proc_stat_operations = {
 444         .open           = stat_open,
 445         .read           = seq_read,
 446         .llseek         = seq_lseek,
 447         .release        = single_release,
 448 };
 449
 450 static int devices_read_proc(char *page, char **start, off_t off,
 451                                  int count, int *eof, void *data)
 452 {
 453         int len = get_chrdev_list(page);
 454         len += get_blkdev_list(page+len);
 455         return proc_calc_metrics(page, start, off, count, eof, len);
 456 }
 457
 458 /*
 459  * /proc/interrupts
 460  */
 461 static void *int_seq_start(struct seq_file *f, loff_t *pos)
 462 {
 463         return (*pos <= NR_IRQS) ? pos : NULL;
 464 }
 465
 466 static void *int_seq_next(struct seq_file *f, void *v, loff_t *pos)
 467 {
 468         (*pos)++;
 469         if (*pos > NR_IRQS)
 470                 return NULL;
 471         return pos;
 472 }
 473
 474 static void int_seq_stop(struct seq_file *f, void *v)
 475 {
 476         /* Nothing to do */
 477 }
 478
 479
 480 extern int show_interrupts(struct seq_file *f, void *v); /* In arch code */
 481 static struct seq_operations int_seq_ops = {
 482         .start = int_seq_start,
 483         .next  = int_seq_next,
 484         .stop  = int_seq_stop,
 485         .show  = show_interrupts
 486 };
 487
 488 static int interrupts_open(struct inode *inode, struct file *filp)
 489 {
 490         return seq_open(filp, &int_seq_ops);
 491 }
 492
 493 static struct file_operations proc_interrupts_operations = {
 494         .open           = interrupts_open,
 495         .read           = seq_read,
 496         .llseek         = seq_lseek,
 497         .release        = seq_release,
 498 };
 499
 500 static int filesystems_read_proc(char *page, char **start, off_t off,
 501                                  int count, int *eof, void *data)
 502 {
 503         int len = get_filesystem_list(page);
 504         return proc_calc_metrics(page, start, off, count, eof, len);
 505 }
 506
 507 static int cmdline_read_proc(char *page, char **start, off_t off,
 508                                  int count, int *eof, void *data)
 509 {
 510         int len;
 511
 512         len = sprintf(page, "%s\n", saved_command_line);
 513         return proc_calc_metrics(page, start, off, count, eof, len);
 514 }
 515
 516 static int locks_read_proc(char *page, char **start, off_t off,
 517                                  int count, int *eof, void *data)
 518 {
 519         int len = get_locks_status(page, start, off, count);
 520
 521         if (len < count)
 522                 *eof = 1;
 523         return len;
 524 }
 525
 526 static int execdomains_read_proc(char *page, char **start, off_t off,
 527                                  int count, int *eof, void *data)
 528 {
 529         int len = get_exec_domain_list(page);
 530         return proc_calc_metrics(page, start, off, count, eof, len);
 531 }
 532
 533 #ifdef CONFIG_MAGIC_SYSRQ
 534 /*
 535  * writing 'C' to /proc/sysrq-trigger is like sysrq-C
 536  */
 537 static ssize_t write_sysrq_trigger(struct file *file, const char __user *buf,
 538                                    size_t count, loff_t *ppos)
 539 {
 540         if (count) {
 541                 char c;
 542
 543                 if (get_user(c, buf))
 544                         return -EFAULT;
 545                 __handle_sysrq(c, NULL, NULL, 0);
 546         }
 547         return count;
 548 }
 549
 550 static struct file_operations proc_sysrq_trigger_operations = {
 551         .write          = write_sysrq_trigger,
 552 };
 553 #endif
 554
 555 struct proc_dir_entry *proc_root_kcore;
 556
 557 void create_seq_entry(char *name, mode_t mode, struct file_operations *f)
 558 {
 559         struct proc_dir_entry *entry;
 560         entry = create_proc_entry(name, mode, NULL);
 561         if (entry)
 562                 entry->proc_fops = f;
 563 }
 564
 565 void __init proc_misc_init(void)
 566 {
 567         struct proc_dir_entry *entry;
 568         static struct {
 569                 char *name;
 570                 int (*read_proc)(char*,char**,off_t,int,int*,void*);
 571         } *p, simple_ones[] = {
 572                 {"loadavg",     loadavg_read_proc},
 573                 {"uptime",      uptime_read_proc},
 574                 {"meminfo",     meminfo_read_proc},
 575                 {"version",     version_read_proc},
 576 #ifdef CONFIG_PROC_HARDWARE
 577                 {"hardware",    hardware_read_proc},
 578 #endif
 579 #ifdef CONFIG_STRAM_PROC
 580                 {"stram",       stram_read_proc},
 581 #endif
 582                 {"devices",     devices_read_proc},
 583                 {"filesystems", filesystems_read_proc},
 584                 {"cmdline",     cmdline_read_proc},
 585                 {"locks",       locks_read_proc},
 586                 {"execdomains", execdomains_read_proc},
 587                 {NULL,}
 588         };
 589         for (p = simple_ones; p->name; p++)
 590                 create_proc_read_entry(p->name, 0, NULL, p->read_proc, NULL);
 591
 592         proc_symlink("mounts", NULL, "self/mounts");
 593
 594         /* And now for trickier ones */
 595         entry = create_proc_entry("kmsg", S_IRUSR, &proc_root);
 596         if (entry)
 597                 entry->proc_fops = &proc_kmsg_operations;
 598         create_seq_entry("cpuinfo", 0, &proc_cpuinfo_operations);
 599         create_seq_entry("partitions", 0, &proc_partitions_operations);
 600         create_seq_entry("stat", 0, &proc_stat_operations);
 601         create_seq_entry("interrupts", 0, &proc_interrupts_operations);
 602         create_seq_entry("slabinfo",S_IWUSR|S_IRUGO,&proc_slabinfo_operations);
 603         create_seq_entry("buddyinfo",S_IRUGO, &fragmentation_file_operations);
 604         create_seq_entry("vmstat",S_IRUGO, &proc_vmstat_file_operations);
 605         create_seq_entry("zoneinfo",S_IRUGO, &proc_zoneinfo_file_operations);
 606         create_seq_entry("diskstats", 0, &proc_diskstats_operations);
 607 #ifdef CONFIG_MODULES
 608         create_seq_entry("modules", 0, &proc_modules_operations);
 609 #endif
 610 #ifdef CONFIG_SCHEDSTATS
 611         create_seq_entry("schedstat", 0, &proc_schedstat_operations);
 612 #endif
 613 #ifdef CONFIG_PROC_KCORE
 614         proc_root_kcore = create_proc_entry("kcore", S_IRUSR, NULL);
 615         if (proc_root_kcore) {
 616                 proc_root_kcore->proc_fops = &proc_kcore_operations;
 617                 proc_root_kcore->size =
 618                                 (size_t)high_memory - PAGE_OFFSET + PAGE_SIZE;
 619         }
 620 #endif
 621 #ifdef CONFIG_MAGIC_SYSRQ
 622         entry = create_proc_entry("sysrq-trigger", S_IWUSR, NULL);
 623         if (entry)
 624                 entry->proc_fops = &proc_sysrq_trigger_operations;
 625 #endif
 626 #ifdef CONFIG_PPC32
 627         {
 628                 extern struct file_operations ppc_htab_operations;
 629                 entry = create_proc_entry("ppc_htab", S_IRUGO|S_IWUSR, NULL);
 630                 if (entry)
 631                         entry->proc_fops = &ppc_htab_operations;
 632         }
 633 #endif
 634 }