Pileus Git - ~andy/linux/blob - drivers/staging/lustre/lustre/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, 2012, Intel Corporation.
  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 <linux/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 init_waitqueue_entry_current(wait_queue_t *link)
  54 {
  55         init_waitqueue_entry(LINUX_WAITQ(link), current);
  56 }
  57 EXPORT_SYMBOL(init_waitqueue_entry_current);
  58
  59 /**
  60  * wait_queue_t of Linux (version < 2.6.34) is a FIFO list for exclusively
  61  * waiting threads, which is not always desirable because all threads will
  62  * be waken up again and again, even user only needs a few of them to be
  63  * active most time. This is not good for performance because cache can
  64  * be polluted by different threads.
  65  *
  66  * LIFO list can resolve this problem because we always wakeup the most
  67  * recent active thread by default.
  68  *
  69  * NB: please don't call non-exclusive & exclusive wait on the same
  70  * waitq if add_wait_queue_exclusive_head is used.
  71  */
  72 void
  73 add_wait_queue_exclusive_head(wait_queue_head_t *waitq, wait_queue_t *link)
  74 {
  75         unsigned long flags;
  76
  77         spin_lock_irqsave(&LINUX_WAITQ_HEAD(waitq)->lock, flags);
  78         __add_wait_queue_exclusive(LINUX_WAITQ_HEAD(waitq), LINUX_WAITQ(link));
  79         spin_unlock_irqrestore(&LINUX_WAITQ_HEAD(waitq)->lock, flags);
  80 }
  81 EXPORT_SYMBOL(add_wait_queue_exclusive_head);
  82
  83 void
  84 waitq_wait(wait_queue_t *link, long state)
  85 {
  86         schedule();
  87 }
  88 EXPORT_SYMBOL(waitq_wait);
  89
  90 int64_t
  91 waitq_timedwait(wait_queue_t *link, long state, int64_t timeout)
  92 {
  93         return schedule_timeout(timeout);
  94 }
  95 EXPORT_SYMBOL(waitq_timedwait);
  96
  97 void
  98 schedule_timeout_and_set_state(long state, int64_t timeout)
  99 {
 100         set_current_state(state);
 101         schedule_timeout(timeout);
 102 }
 103 EXPORT_SYMBOL(schedule_timeout_and_set_state);
 104
 105 /* deschedule for a bit... */
 106 void
 107 cfs_pause(cfs_duration_t ticks)
 108 {
 109         set_current_state(TASK_UNINTERRUPTIBLE);
 110         schedule_timeout(ticks);
 111 }
 112 EXPORT_SYMBOL(cfs_pause);
 113
 114 void cfs_init_timer(struct timer_list *t)
 115 {
 116         init_timer(t);
 117 }
 118 EXPORT_SYMBOL(cfs_init_timer);
 119
 120 void cfs_timer_init(struct timer_list *t, cfs_timer_func_t *func, void *arg)
 121 {
 122         init_timer(t);
 123         t->function = func;
 124         t->data = (unsigned long)arg;
 125 }
 126 EXPORT_SYMBOL(cfs_timer_init);
 127
 128 void cfs_timer_done(struct timer_list *t)
 129 {
 130         return;
 131 }
 132 EXPORT_SYMBOL(cfs_timer_done);
 133
 134 void cfs_timer_arm(struct timer_list *t, cfs_time_t deadline)
 135 {
 136         mod_timer(t, deadline);
 137 }
 138 EXPORT_SYMBOL(cfs_timer_arm);
 139
 140 void cfs_timer_disarm(struct timer_list *t)
 141 {
 142         del_timer(t);
 143 }
 144 EXPORT_SYMBOL(cfs_timer_disarm);
 145
 146 int  cfs_timer_is_armed(struct timer_list *t)
 147 {
 148         return timer_pending(t);
 149 }
 150 EXPORT_SYMBOL(cfs_timer_is_armed);
 151
 152 cfs_time_t cfs_timer_deadline(struct timer_list *t)
 153 {
 154         return t->expires;
 155 }
 156 EXPORT_SYMBOL(cfs_timer_deadline);
 157
 158 void cfs_enter_debugger(void)
 159 {
 160 #if defined(CONFIG_KGDB)
 161 //      BREAKPOINT();
 162 #else
 163         /* nothing */
 164 #endif
 165 }
 166
 167
 168 sigset_t
 169 cfs_block_allsigs(void)
 170 {
 171         unsigned long     flags;
 172         sigset_t        old;
 173
 174         SIGNAL_MASK_LOCK(current, flags);
 175         old = current->blocked;
 176         sigfillset(&current->blocked);
 177         recalc_sigpending();
 178         SIGNAL_MASK_UNLOCK(current, flags);
 179
 180         return old;
 181 }
 182
 183 sigset_t cfs_block_sigs(unsigned long sigs)
 184 {
 185         unsigned long  flags;
 186         sigset_t        old;
 187
 188         SIGNAL_MASK_LOCK(current, flags);
 189         old = current->blocked;
 190         sigaddsetmask(&current->blocked, sigs);
 191         recalc_sigpending();
 192         SIGNAL_MASK_UNLOCK(current, flags);
 193         return old;
 194 }
 195
 196 /* Block all signals except for the @sigs */
 197 sigset_t cfs_block_sigsinv(unsigned long sigs)
 198 {
 199         unsigned long flags;
 200         sigset_t old;
 201
 202         SIGNAL_MASK_LOCK(current, flags);
 203         old = current->blocked;
 204         sigaddsetmask(&current->blocked, ~sigs);
 205         recalc_sigpending();
 206         SIGNAL_MASK_UNLOCK(current, flags);
 207
 208         return old;
 209 }
 210
 211 void
 212 cfs_restore_sigs (sigset_t old)
 213 {
 214         unsigned long  flags;
 215
 216         SIGNAL_MASK_LOCK(current, flags);
 217         current->blocked = old;
 218         recalc_sigpending();
 219         SIGNAL_MASK_UNLOCK(current, flags);
 220 }
 221
 222 int
 223 cfs_signal_pending(void)
 224 {
 225         return signal_pending(current);
 226 }
 227
 228 void
 229 cfs_clear_sigpending(void)
 230 {
 231         unsigned long flags;
 232
 233         SIGNAL_MASK_LOCK(current, flags);
 234         clear_tsk_thread_flag(current, TIF_SIGPENDING);
 235         SIGNAL_MASK_UNLOCK(current, flags);
 236 }
 237
 238 int
 239 libcfs_arch_init(void)
 240 {
 241         return 0;
 242 }
 243
 244 void
 245 libcfs_arch_cleanup(void)
 246 {
 247         return;
 248 }
 249
 250 EXPORT_SYMBOL(libcfs_arch_init);
 251 EXPORT_SYMBOL(libcfs_arch_cleanup);
 252 EXPORT_SYMBOL(cfs_enter_debugger);
 253 EXPORT_SYMBOL(cfs_block_allsigs);
 254 EXPORT_SYMBOL(cfs_block_sigs);
 255 EXPORT_SYMBOL(cfs_block_sigsinv);
 256 EXPORT_SYMBOL(cfs_restore_sigs);
 257 EXPORT_SYMBOL(cfs_signal_pending);
 258 EXPORT_SYMBOL(cfs_clear_sigpending);