fs/gfs2/daemon.c

   1 /*
   2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   3  * Copyright (C) 2004-2006 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 version 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 <linux/gfs2_ondisk.h>
  18 #include <linux/lm_interface.h>
  19 #include <linux/freezer.h>
  20
  21 #include "gfs2.h"
  22 #include "incore.h"
  23 #include "daemon.h"
  24 #include "glock.h"
  25 #include "log.h"
  26 #include "quota.h"
  27 #include "recovery.h"
  28 #include "super.h"
  29 #include "util.h"
  30
  31 /* This uses schedule_timeout() instead of msleep() because it's good for
  32    the daemons to wake up more often than the timeout when unmounting so
  33    the user's unmount doesn't sit there forever.
  34
  35    The kthread functions used to start these daemons block and flush signals. */
  36
  37 /**
  38  * gfs2_glockd - Reclaim unused glock structures
  39  * @sdp: Pointer to GFS2 superblock
  40  *
  41  * One or more of these daemons run, reclaiming glocks on sd_reclaim_list.
  42  * Number of daemons can be set by user, with num_glockd mount option.
  43  */
  44
  45 int gfs2_glockd(void *data)
  46 {
  47         struct gfs2_sbd *sdp = data;
  48
  49         while (!kthread_should_stop()) {
  50                 while (atomic_read(&sdp->sd_reclaim_count))
  51                         gfs2_reclaim_glock(sdp);
  52
  53                 wait_event_interruptible(sdp->sd_reclaim_wq,
  54                                          (atomic_read(&sdp->sd_reclaim_count) ||
  55                                          kthread_should_stop()));
  56                 if (freezing(current))
  57                         refrigerator();
  58         }
  59
  60         return 0;
  61 }
  62
  63 /**
  64  * gfs2_recoverd - Recover dead machine's journals
  65  * @sdp: Pointer to GFS2 superblock
  66  *
  67  */
  68
  69 int gfs2_recoverd(void *data)
  70 {
  71         struct gfs2_sbd *sdp = data;
  72         unsigned long t;
  73
  74         while (!kthread_should_stop()) {
  75                 gfs2_check_journals(sdp);
  76                 t = gfs2_tune_get(sdp,  gt_recoverd_secs) * HZ;
  77                 if (freezing(current))
  78                         refrigerator();
  79                 schedule_timeout_interruptible(t);
  80         }
  81
  82         return 0;
  83 }
  84
  85 /**
  86  * gfs2_quotad - Write cached quota changes into the quota file
  87  * @sdp: Pointer to GFS2 superblock
  88  *
  89  */
  90
  91 int gfs2_quotad(void *data)
  92 {
  93         struct gfs2_sbd *sdp = data;
  94         unsigned long t;
  95         int error;
  96
  97         while (!kthread_should_stop()) {
  98                 /* Update the master statfs file */
  99
 100                 t = sdp->sd_statfs_sync_time +
 101                     gfs2_tune_get(sdp, gt_statfs_quantum) * HZ;
 102
 103                 if (time_after_eq(jiffies, t)) {
 104                         error = gfs2_statfs_sync(sdp);
 105                         if (error &&
 106                             error != -EROFS &&
 107                             !test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
 108                                 fs_err(sdp, "quotad: (1) error=%d\n", error);
 109                         sdp->sd_statfs_sync_time = jiffies;
 110                 }
 111
 112                 /* Update quota file */
 113
 114                 t = sdp->sd_quota_sync_time +
 115                     gfs2_tune_get(sdp, gt_quota_quantum) * HZ;
 116
 117                 if (time_after_eq(jiffies, t)) {
 118                         error = gfs2_quota_sync(sdp);
 119                         if (error &&
 120                             error != -EROFS &&
 121                             !test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
 122                                 fs_err(sdp, "quotad: (2) error=%d\n", error);
 123                         sdp->sd_quota_sync_time = jiffies;
 124                 }
 125
 126                 gfs2_quota_scan(sdp);
 127
 128                 t = gfs2_tune_get(sdp, gt_quotad_secs) * HZ;
 129                 if (freezing(current))
 130                         refrigerator();
 131                 schedule_timeout_interruptible(t);
 132         }
 133
 134         return 0;
 135 }
 136