[GFS2] The core of GFS2

This patch contains all the core files for GFS2.

Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

1 files changed, 225 insertions, 0 deletions

diff --git a/fs/gfs2/daemon.c b/fs/gfs2/daemon.c
new file mode 100644
index 0000000..cff8d53
--- /dev/null
+++ b/fs/gfs2/daemon.c
@@ -0,0 +1,225 @@
+/*
+ * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
+ * Copyright (C) 2004-2005 Red Hat, Inc.  All rights reserved.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU General Public License v.2.
+ */
+
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/completion.h>
+#include <linux/buffer_head.h>
+#include <linux/kthread.h>
+#include <linux/delay.h>
+#include <asm/semaphore.h>
+
+#include "gfs2.h"
+#include "daemon.h"
+#include "glock.h"
+#include "log.h"
+#include "quota.h"
+#include "recovery.h"
+#include "super.h"
+#include "unlinked.h"
+
+/* This uses schedule_timeout() instead of msleep() because it's good for
+   the daemons to wake up more often than the timeout when unmounting so
+   the user's unmount doesn't sit there forever.
+   
+   The kthread functions used to start these daemons block and flush signals. */
+
+/**
+ * gfs2_scand - Look for cached glocks and inodes to toss from memory
+ * @sdp: Pointer to GFS2 superblock
+ *
+ * One of these daemons runs, finding candidates to add to sd_reclaim_list.
+ * See gfs2_glockd()
+ */
+
+int gfs2_scand(void *data)
+{
+	struct gfs2_sbd *sdp = (struct gfs2_sbd *)data;
+	unsigned long t;
+
+	while (!kthread_should_stop()) {
+		gfs2_scand_internal(sdp);
+		t = gfs2_tune_get(sdp, gt_scand_secs) * HZ;
+		schedule_timeout_interruptible(t);
+	}
+
+	return 0;
+}
+
+/**
+ * gfs2_glockd - Reclaim unused glock structures
+ * @sdp: Pointer to GFS2 superblock
+ *
+ * One or more of these daemons run, reclaiming glocks on sd_reclaim_list.
+ * Number of daemons can be set by user, with num_glockd mount option.
+ */
+
+int gfs2_glockd(void *data)
+{
+	struct gfs2_sbd *sdp = (struct gfs2_sbd *)data;
+	DECLARE_WAITQUEUE(wait_chan, current);
+
+	while (!kthread_should_stop()) {
+		while (atomic_read(&sdp->sd_reclaim_count))
+			gfs2_reclaim_glock(sdp);
+
+		set_current_state(TASK_INTERRUPTIBLE);
+		add_wait_queue(&sdp->sd_reclaim_wq, &wait_chan);
+		if (!atomic_read(&sdp->sd_reclaim_count) &&
+		    !kthread_should_stop())
+			schedule();
+		remove_wait_queue(&sdp->sd_reclaim_wq, &wait_chan);
+		set_current_state(TASK_RUNNING);
+	}
+
+	return 0;
+}
+
+/**
+ * gfs2_recoverd - Recover dead machine's journals
+ * @sdp: Pointer to GFS2 superblock
+ *
+ */
+
+int gfs2_recoverd(void *data)
+{
+	struct gfs2_sbd *sdp = (struct gfs2_sbd *)data;
+	unsigned long t;
+
+	while (!kthread_should_stop()) {
+		gfs2_check_journals(sdp);
+		t = gfs2_tune_get(sdp,  gt_recoverd_secs) * HZ;
+		schedule_timeout_interruptible(t);
+	}
+
+	return 0;
+}
+
+/**
+ * gfs2_logd - Update log tail as Active Items get flushed to in-place blocks
+ * @sdp: Pointer to GFS2 superblock
+ *
+ * Also, periodically check to make sure that we're using the most recent
+ * journal index.
+ */
+
+int gfs2_logd(void *data)
+{
+	struct gfs2_sbd *sdp = (struct gfs2_sbd *)data;
+	struct gfs2_holder ji_gh;
+	unsigned long t;
+
+	while (!kthread_should_stop()) {
+		/* Advance the log tail */
+
+		t = sdp->sd_log_flush_time +
+		    gfs2_tune_get(sdp, gt_log_flush_secs) * HZ;
+
+		gfs2_ail1_empty(sdp, DIO_ALL);
+
+		if (time_after_eq(jiffies, t)) {
+			gfs2_log_flush(sdp);
+			sdp->sd_log_flush_time = jiffies;
+		}
+
+		/* Check for latest journal index */
+
+		t = sdp->sd_jindex_refresh_time +
+		    gfs2_tune_get(sdp, gt_jindex_refresh_secs) * HZ;
+
+		if (time_after_eq(jiffies, t)) {
+			if (!gfs2_jindex_hold(sdp, &ji_gh))
+				gfs2_glock_dq_uninit(&ji_gh);
+			sdp->sd_jindex_refresh_time = jiffies;
+		}
+
+		t = gfs2_tune_get(sdp, gt_logd_secs) * HZ;
+		schedule_timeout_interruptible(t);
+	}
+
+	return 0;
+}
+
+/**
+ * gfs2_quotad - Write cached quota changes into the quota file
+ * @sdp: Pointer to GFS2 superblock
+ *
+ */
+
+int gfs2_quotad(void *data)
+{
+	struct gfs2_sbd *sdp = (struct gfs2_sbd *)data;
+	unsigned long t;
+	int error;
+
+	while (!kthread_should_stop()) {
+		/* Update the master statfs file */
+
+		t = sdp->sd_statfs_sync_time +
+		    gfs2_tune_get(sdp, gt_statfs_quantum) * HZ;
+
+		if (time_after_eq(jiffies, t)) {
+			error = gfs2_statfs_sync(sdp);
+			if (error &&
+			    error != -EROFS &&
+			    !test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
+				fs_err(sdp, "quotad: (1) error=%d\n", error);
+			sdp->sd_statfs_sync_time = jiffies;
+		}
+
+		/* Update quota file */
+
+		t = sdp->sd_quota_sync_time +
+		    gfs2_tune_get(sdp, gt_quota_quantum) * HZ;
+
+		if (time_after_eq(jiffies, t)) {
+			error = gfs2_quota_sync(sdp);
+			if (error &&
+			    error != -EROFS &&
+			    !test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
+				fs_err(sdp, "quotad: (2) error=%d\n", error);
+			sdp->sd_quota_sync_time = jiffies;
+		}
+
+		gfs2_quota_scan(sdp);
+
+		t = gfs2_tune_get(sdp, gt_quotad_secs) * HZ;
+		schedule_timeout_interruptible(t);
+	}
+
+	return 0;
+}
+
+/**
+ * gfs2_inoded - Deallocate unlinked inodes
+ * @sdp: Pointer to GFS2 superblock
+ *
+ */
+
+int gfs2_inoded(void *data)
+{
+	struct gfs2_sbd *sdp = (struct gfs2_sbd *)data;
+	unsigned long t;
+	int error;
+
+	while (!kthread_should_stop()) {
+		error = gfs2_unlinked_dealloc(sdp);
+		if (error &&
+		    error != -EROFS &&
+		    !test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
+			fs_err(sdp, "inoded: error = %d\n", error);
+
+		t = gfs2_tune_get(sdp, gt_inoded_secs) * HZ;
+		schedule_timeout_interruptible(t);
+	}
+
+	return 0;
+}
+