libcfs/libcfs/linux/linux-prim.c

   1 /*
   2  * GPL HEADER START
   3  *
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 only,
   8  * as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License version 2 for more details (a copy is included
  14  * in the LICENSE file that accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * version 2 along with this program; If not, see
  18  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
  19  *
  20  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  21  * CA 95054 USA or visit www.sun.com if you need additional information or
  22  * have any questions.
  23  *
  24  * GPL HEADER END
  25  */
  26 /*
  27  * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
  28  * Use is subject to license terms.
  29  *
  30  * Copyright (c) 2011, Whamcloud, Inc.
  31  */
  32 /*
  33  * This file is part of Lustre, http://www.lustre.org/
  34  * Lustre is a trademark of Sun Microsystems, Inc.
  35  */
  36
  37 #define DEBUG_SUBSYSTEM S_LNET
  38 #include <linux/module.h>
  39 #include <linux/kernel.h>
  40 #include <linux/fs_struct.h>
  41 #include <linux/sched.h>
  42
  43 #include <libcfs/libcfs.h>
  44
  45 #if defined(CONFIG_KGDB)
  46 #include <asm/kgdb.h>
  47 #endif
  48
  49 #define LINUX_WAITQ(w) ((wait_queue_t *) w)
  50 #define LINUX_WAITQ_HEAD(w) ((wait_queue_head_t *) w)
  51
  52 void
  53 cfs_waitq_init(cfs_waitq_t *waitq)
  54 {
  55         init_waitqueue_head(LINUX_WAITQ_HEAD(waitq));
  56 }
  57 EXPORT_SYMBOL(cfs_waitq_init);
  58
  59 void
  60 cfs_waitlink_init(cfs_waitlink_t *link)
  61 {
  62         init_waitqueue_entry(LINUX_WAITQ(link), current);
  63 }
  64 EXPORT_SYMBOL(cfs_waitlink_init);
  65
  66 void
  67 cfs_waitq_add(cfs_waitq_t *waitq, cfs_waitlink_t *link)
  68 {
  69         add_wait_queue(LINUX_WAITQ_HEAD(waitq), LINUX_WAITQ(link));
  70 }
  71 EXPORT_SYMBOL(cfs_waitq_add);
  72
  73 #ifndef HAVE___ADD_WAIT_QUEUE_EXCLUSIVE
  74
  75 static inline void __add_wait_queue_exclusive(wait_queue_head_t *q,
  76                                               wait_queue_t *wait)
  77 {
  78         wait->flags |= WQ_FLAG_EXCLUSIVE;
  79         __add_wait_queue(q, wait);
  80 }
  81
  82 #endif /* HAVE___ADD_WAIT_QUEUE_EXCLUSIVE */
  83
  84 void
  85 cfs_waitq_add_exclusive(cfs_waitq_t *waitq,
  86                         cfs_waitlink_t *link)
  87 {
  88         add_wait_queue_exclusive(LINUX_WAITQ_HEAD(waitq), LINUX_WAITQ(link));
  89 }
  90 EXPORT_SYMBOL(cfs_waitq_add_exclusive);
  91
  92 /**
  93  * wait_queue_t of Linux (version < 2.6.34) is a FIFO list for exclusively
  94  * waiting threads, which is not always desirable because all threads will
  95  * be waken up again and again, even user only needs a few of them to be
  96  * active most time. This is not good for performance because cache can
  97  * be polluted by different threads.
  98  *
  99  * LIFO list can resolve this problem because we always wakeup the most
 100  * recent active thread by default.
 101  *
 102  * NB: please don't call non-exclusive & exclusive wait on the same
 103  * waitq if cfs_waitq_add_exclusive_head is used.
 104  */
 105 void
 106 cfs_waitq_add_exclusive_head(cfs_waitq_t *waitq, cfs_waitlink_t *link)
 107 {
 108         unsigned long flags;
 109
 110         spin_lock_irqsave(&LINUX_WAITQ_HEAD(waitq)->lock, flags);
 111         __add_wait_queue_exclusive(LINUX_WAITQ_HEAD(waitq), LINUX_WAITQ(link));
 112         spin_unlock_irqrestore(&LINUX_WAITQ_HEAD(waitq)->lock, flags);
 113 }
 114 EXPORT_SYMBOL(cfs_waitq_add_exclusive_head);
 115
 116 void
 117 cfs_waitq_del(cfs_waitq_t *waitq, cfs_waitlink_t *link)
 118 {
 119         remove_wait_queue(LINUX_WAITQ_HEAD(waitq), LINUX_WAITQ(link));
 120 }
 121 EXPORT_SYMBOL(cfs_waitq_del);
 122
 123 int
 124 cfs_waitq_active(cfs_waitq_t *waitq)
 125 {
 126         return waitqueue_active(LINUX_WAITQ_HEAD(waitq));
 127 }
 128 EXPORT_SYMBOL(cfs_waitq_active);
 129
 130 void
 131 cfs_waitq_signal(cfs_waitq_t *waitq)
 132 {
 133         wake_up(LINUX_WAITQ_HEAD(waitq));
 134 }
 135 EXPORT_SYMBOL(cfs_waitq_signal);
 136
 137 void
 138 cfs_waitq_signal_nr(cfs_waitq_t *waitq, int nr)
 139 {
 140         wake_up_nr(LINUX_WAITQ_HEAD(waitq), nr);
 141 }
 142 EXPORT_SYMBOL(cfs_waitq_signal_nr);
 143
 144 void
 145 cfs_waitq_broadcast(cfs_waitq_t *waitq)
 146 {
 147         wake_up_all(LINUX_WAITQ_HEAD(waitq));
 148 }
 149 EXPORT_SYMBOL(cfs_waitq_broadcast);
 150
 151 void
 152 cfs_waitq_wait(cfs_waitlink_t *link, cfs_task_state_t state)
 153 {
 154         schedule();
 155 }
 156 EXPORT_SYMBOL(cfs_waitq_wait);
 157
 158 int64_t
 159 cfs_waitq_timedwait(cfs_waitlink_t *link, cfs_task_state_t state,
 160                     int64_t timeout)
 161 {
 162         return schedule_timeout(timeout);
 163 }
 164 EXPORT_SYMBOL(cfs_waitq_timedwait);
 165
 166 void
 167 cfs_schedule_timeout_and_set_state(cfs_task_state_t state, int64_t timeout)
 168 {
 169         set_current_state(state);
 170         schedule_timeout(timeout);
 171 }
 172 EXPORT_SYMBOL(cfs_schedule_timeout_and_set_state);
 173
 174 void
 175 cfs_schedule_timeout(int64_t timeout)
 176 {
 177         schedule_timeout(timeout);
 178 }
 179 EXPORT_SYMBOL(cfs_schedule_timeout);
 180
 181 void
 182 cfs_schedule(void)
 183 {
 184         schedule();
 185 }
 186 EXPORT_SYMBOL(cfs_schedule);
 187
 188 /* deschedule for a bit... */
 189 void
 190 cfs_pause(cfs_duration_t ticks)
 191 {
 192         set_current_state(TASK_UNINTERRUPTIBLE);
 193         schedule_timeout(ticks);
 194 }
 195 EXPORT_SYMBOL(cfs_pause);
 196
 197 int cfs_need_resched(void)
 198 {
 199         return need_resched();
 200 }
 201 EXPORT_SYMBOL(cfs_need_resched);
 202
 203 void cfs_cond_resched(void)
 204 {
 205         cond_resched();
 206 }
 207 EXPORT_SYMBOL(cfs_cond_resched);
 208
 209 void cfs_init_timer(cfs_timer_t *t)
 210 {
 211         init_timer(t);
 212 }
 213 EXPORT_SYMBOL(cfs_init_timer);
 214
 215 void cfs_timer_init(cfs_timer_t *t, cfs_timer_func_t *func, void *arg)
 216 {
 217         init_timer(t);
 218         t->function = func;
 219         t->data = (unsigned long)arg;
 220 }
 221 EXPORT_SYMBOL(cfs_timer_init);
 222
 223 void cfs_timer_done(cfs_timer_t *t)
 224 {
 225         return;
 226 }
 227 EXPORT_SYMBOL(cfs_timer_done);
 228
 229 void cfs_timer_arm(cfs_timer_t *t, cfs_time_t deadline)
 230 {
 231         mod_timer(t, deadline);
 232 }
 233 EXPORT_SYMBOL(cfs_timer_arm);
 234
 235 void cfs_timer_disarm(cfs_timer_t *t)
 236 {
 237         del_timer(t);
 238 }
 239 EXPORT_SYMBOL(cfs_timer_disarm);
 240
 241 int  cfs_timer_is_armed(cfs_timer_t *t)
 242 {
 243         return timer_pending(t);
 244 }
 245 EXPORT_SYMBOL(cfs_timer_is_armed);
 246
 247 cfs_time_t cfs_timer_deadline(cfs_timer_t *t)
 248 {
 249         return t->expires;
 250 }
 251 EXPORT_SYMBOL(cfs_timer_deadline);
 252
 253 void cfs_enter_debugger(void)
 254 {
 255 #if defined(CONFIG_KGDB)
 256 //        BREAKPOINT();
 257 #elif defined(__arch_um__)
 258         asm("int $3");
 259 #else
 260         /* nothing */
 261 #endif
 262 }
 263
 264 void cfs_daemonize(char *str) {
 265         unsigned long flags;
 266
 267         daemonize(str);
 268         SIGNAL_MASK_LOCK(current, flags);
 269         sigfillset(&current->blocked);
 270         RECALC_SIGPENDING;
 271         SIGNAL_MASK_UNLOCK(current, flags);
 272 }
 273
 274 int cfs_daemonize_ctxt(char *str) {
 275
 276         cfs_daemonize(str);
 277 #ifndef HAVE_UNSHARE_FS_STRUCT
 278         {
 279         struct task_struct *tsk = current;
 280         struct fs_struct *fs = NULL;
 281         fs = copy_fs_struct(tsk->fs);
 282         if (fs == NULL)
 283                 return -ENOMEM;
 284         exit_fs(tsk);
 285         tsk->fs = fs;
 286         }
 287 #else
 288         unshare_fs_struct();
 289 #endif
 290         return 0;
 291 }
 292
 293 sigset_t
 294 cfs_block_allsigs(void)
 295 {
 296         unsigned long          flags;
 297         sigset_t        old;
 298
 299         SIGNAL_MASK_LOCK(current, flags);
 300         old = current->blocked;
 301         sigfillset(&current->blocked);
 302         RECALC_SIGPENDING;
 303         SIGNAL_MASK_UNLOCK(current, flags);
 304
 305         return old;
 306 }
 307
 308 sigset_t cfs_block_sigs(unsigned long sigs)
 309 {
 310         unsigned long  flags;
 311         sigset_t        old;
 312
 313         SIGNAL_MASK_LOCK(current, flags);
 314         old = current->blocked;
 315         sigaddsetmask(&current->blocked, sigs);
 316         RECALC_SIGPENDING;
 317         SIGNAL_MASK_UNLOCK(current, flags);
 318         return old;
 319 }
 320
 321 /* Block all signals except for the @sigs */
 322 sigset_t cfs_block_sigsinv(unsigned long sigs)
 323 {
 324         unsigned long flags;
 325         sigset_t old;
 326
 327         SIGNAL_MASK_LOCK(current, flags);
 328         old = current->blocked;
 329         sigaddsetmask(&current->blocked, ~sigs);
 330         RECALC_SIGPENDING;
 331         SIGNAL_MASK_UNLOCK(current, flags);
 332
 333         return old;
 334 }
 335
 336 void
 337 cfs_restore_sigs (cfs_sigset_t old)
 338 {
 339         unsigned long  flags;
 340
 341         SIGNAL_MASK_LOCK(current, flags);
 342         current->blocked = old;
 343         RECALC_SIGPENDING;
 344         SIGNAL_MASK_UNLOCK(current, flags);
 345 }
 346
 347 int
 348 cfs_signal_pending(void)
 349 {
 350         return signal_pending(current);
 351 }
 352
 353 void
 354 cfs_clear_sigpending(void)
 355 {
 356         unsigned long flags;
 357
 358         SIGNAL_MASK_LOCK(current, flags);
 359         CLEAR_SIGPENDING;
 360         SIGNAL_MASK_UNLOCK(current, flags);
 361 }
 362
 363 int
 364 libcfs_arch_init(void)
 365 {
 366         return 0;
 367 }
 368
 369 void
 370 libcfs_arch_cleanup(void)
 371 {
 372         return;
 373 }
 374
 375 EXPORT_SYMBOL(libcfs_arch_init);
 376 EXPORT_SYMBOL(libcfs_arch_cleanup);
 377 EXPORT_SYMBOL(cfs_enter_debugger);
 378 EXPORT_SYMBOL(cfs_daemonize);
 379 EXPORT_SYMBOL(cfs_daemonize_ctxt);
 380 EXPORT_SYMBOL(cfs_block_allsigs);
 381 EXPORT_SYMBOL(cfs_block_sigs);
 382 EXPORT_SYMBOL(cfs_block_sigsinv);
 383 EXPORT_SYMBOL(cfs_restore_sigs);
 384 EXPORT_SYMBOL(cfs_signal_pending);
 385 EXPORT_SYMBOL(cfs_clear_sigpending);