fs/gfs2/daemon.c

   1 /*
   2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   3  * Copyright (C) 2004-2005 Red Hat, Inc.  All rights reserved.
   4  *
   5  * This copyrighted material is made available to anyone wishing to use,
   6  * modify, copy, or redistribute it subject to the terms and conditions
   7  * of the GNU General Public License v.2.
   8  */
   9
  10 #include <linux/sched.h>
  11 #include <linux/slab.h>
  12 #include <linux/spinlock.h>
  13 #include <linux/completion.h>
  14 #include <linux/buffer_head.h>
  15 #include <linux/kthread.h>
  16 #include <linux/delay.h>
  17 #include <asm/semaphore.h>
  18
  19 #include "gfs2.h"
  20 #include "daemon.h"
  21 #include "glock.h"
  22 #include "log.h"
  23 #include "quota.h"
  24 #include "recovery.h"
  25 #include "super.h"
  26 #include "unlinked.h"
  27
  28 /* This uses schedule_timeout() instead of msleep() because it's good for
  29    the daemons to wake up more often than the timeout when unmounting so
  30    the user's unmount doesn't sit there forever.
  31
  32    The kthread functions used to start these daemons block and flush signals. */
  33
  34 /**
  35  * gfs2_scand - Look for cached glocks and inodes to toss from memory
  36  * @sdp: Pointer to GFS2 superblock
  37  *
  38  * One of these daemons runs, finding candidates to add to sd_reclaim_list.
  39  * See gfs2_glockd()
  40  */
  41
  42 int gfs2_scand(void *data)
  43 {
  44         struct gfs2_sbd *sdp = (struct gfs2_sbd *)data;
  45         unsigned long t;
  46
  47         while (!kthread_should_stop()) {
  48                 gfs2_scand_internal(sdp);
  49                 t = gfs2_tune_get(sdp, gt_scand_secs) * HZ;
  50                 schedule_timeout_interruptible(t);
  51         }
  52
  53         return 0;
  54 }
  55
  56 /**
  57  * gfs2_glockd - Reclaim unused glock structures
  58  * @sdp: Pointer to GFS2 superblock
  59  *
  60  * One or more of these daemons run, reclaiming glocks on sd_reclaim_list.
  61  * Number of daemons can be set by user, with num_glockd mount option.
  62  */
  63
  64 int gfs2_glockd(void *data)
  65 {
  66         struct gfs2_sbd *sdp = (struct gfs2_sbd *)data;
  67         DECLARE_WAITQUEUE(wait_chan, current);
  68
  69         while (!kthread_should_stop()) {
  70                 while (atomic_read(&sdp->sd_reclaim_count))
  71                         gfs2_reclaim_glock(sdp);
  72
  73                 set_current_state(TASK_INTERRUPTIBLE);
  74                 add_wait_queue(&sdp->sd_reclaim_wq, &wait_chan);
  75                 if (!atomic_read(&sdp->sd_reclaim_count) &&
  76                     !kthread_should_stop())
  77                         schedule();
  78                 remove_wait_queue(&sdp->sd_reclaim_wq, &wait_chan);
  79                 set_current_state(TASK_RUNNING);
  80         }
  81
  82         return 0;
  83 }
  84
  85 /**
  86  * gfs2_recoverd - Recover dead machine's journals
  87  * @sdp: Pointer to GFS2 superblock
  88  *
  89  */
  90
  91 int gfs2_recoverd(void *data)
  92 {
  93         struct gfs2_sbd *sdp = (struct gfs2_sbd *)data;
  94         unsigned long t;
  95
  96         while (!kthread_should_stop()) {
  97                 gfs2_check_journals(sdp);
  98                 t = gfs2_tune_get(sdp,  gt_recoverd_secs) * HZ;
  99                 schedule_timeout_interruptible(t);
 100         }
 101
 102         return 0;
 103 }
 104
 105 /**
 106  * gfs2_logd - Update log tail as Active Items get flushed to in-place blocks
 107  * @sdp: Pointer to GFS2 superblock
 108  *
 109  * Also, periodically check to make sure that we're using the most recent
 110  * journal index.
 111  */
 112
 113 int gfs2_logd(void *data)
 114 {
 115         struct gfs2_sbd *sdp = (struct gfs2_sbd *)data;
 116         struct gfs2_holder ji_gh;
 117         unsigned long t;
 118
 119         while (!kthread_should_stop()) {
 120                 /* Advance the log tail */
 121
 122                 t = sdp->sd_log_flush_time +
 123                     gfs2_tune_get(sdp, gt_log_flush_secs) * HZ;
 124
 125                 gfs2_ail1_empty(sdp, DIO_ALL);
 126
 127                 if (time_after_eq(jiffies, t)) {
 128                         gfs2_log_flush(sdp);
 129                         sdp->sd_log_flush_time = jiffies;
 130                 }
 131
 132                 /* Check for latest journal index */
 133
 134                 t = sdp->sd_jindex_refresh_time +
 135                     gfs2_tune_get(sdp, gt_jindex_refresh_secs) * HZ;
 136
 137                 if (time_after_eq(jiffies, t)) {
 138                         if (!gfs2_jindex_hold(sdp, &ji_gh))
 139                                 gfs2_glock_dq_uninit(&ji_gh);
 140                         sdp->sd_jindex_refresh_time = jiffies;
 141                 }
 142
 143                 t = gfs2_tune_get(sdp, gt_logd_secs) * HZ;
 144                 schedule_timeout_interruptible(t);
 145         }
 146
 147         return 0;
 148 }
 149
 150 /**
 151  * gfs2_quotad - Write cached quota changes into the quota file
 152  * @sdp: Pointer to GFS2 superblock
 153  *
 154  */
 155
 156 int gfs2_quotad(void *data)
 157 {
 158         struct gfs2_sbd *sdp = (struct gfs2_sbd *)data;
 159         unsigned long t;
 160         int error;
 161
 162         while (!kthread_should_stop()) {
 163                 /* Update the master statfs file */
 164
 165                 t = sdp->sd_statfs_sync_time +
 166                     gfs2_tune_get(sdp, gt_statfs_quantum) * HZ;
 167
 168                 if (time_after_eq(jiffies, t)) {
 169                         error = gfs2_statfs_sync(sdp);
 170                         if (error &&
 171                             error != -EROFS &&
 172                             !test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
 173                                 fs_err(sdp, "quotad: (1) error=%d\n", error);
 174                         sdp->sd_statfs_sync_time = jiffies;
 175                 }
 176
 177                 /* Update quota file */
 178
 179                 t = sdp->sd_quota_sync_time +
 180                     gfs2_tune_get(sdp, gt_quota_quantum) * HZ;
 181
 182                 if (time_after_eq(jiffies, t)) {
 183                         error = gfs2_quota_sync(sdp);
 184                         if (error &&
 185                             error != -EROFS &&
 186                             !test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
 187                                 fs_err(sdp, "quotad: (2) error=%d\n", error);
 188                         sdp->sd_quota_sync_time = jiffies;
 189                 }
 190
 191                 gfs2_quota_scan(sdp);
 192
 193                 t = gfs2_tune_get(sdp, gt_quotad_secs) * HZ;
 194                 schedule_timeout_interruptible(t);
 195         }
 196
 197         return 0;
 198 }
 199
 200 /**
 201  * gfs2_inoded - Deallocate unlinked inodes
 202  * @sdp: Pointer to GFS2 superblock
 203  *
 204  */
 205
 206 int gfs2_inoded(void *data)
 207 {
 208         struct gfs2_sbd *sdp = (struct gfs2_sbd *)data;
 209         unsigned long t;
 210         int error;
 211
 212         while (!kthread_should_stop()) {
 213                 error = gfs2_unlinked_dealloc(sdp);
 214                 if (error &&
 215                     error != -EROFS &&
 216                     !test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
 217                         fs_err(sdp, "inoded: error = %d\n", error);
 218
 219                 t = gfs2_tune_get(sdp, gt_inoded_secs) * HZ;
 220                 schedule_timeout_interruptible(t);
 221         }
 222
 223         return 0;
 224 }
 225