libcfs/libcfs/linux/linux-prim.c

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