Example #1
0
File: buffer.c Project: foolsh/elks
void sync_dev(kdev_t dev)
{
    sync_buffers(dev, 0);
    sync_supers(dev);
    sync_inodes(dev);
    sync_buffers(dev, 0);
}
Example #2
0
int fsync_dev(dev_t dev)
{
	sync_buffers(dev, 0);
	sync_supers(dev);
	sync_inodes(dev);
	return sync_buffers(dev, 1);
}
Example #3
0
/*
 * sync everything.  Start out by waking pdflush, because that writes back
 * all queues in parallel.
 */
static void do_sync(unsigned long wait)
{
	wakeup_pdflush(0);
	sync_inodes(0);		/* All mappings, inodes and their blockdevs */
	DQUOT_SYNC(NULL);
	sync_supers();		/* Write the superblocks */
	sync_filesystems(0);	/* Start syncing the filesystems */
	sync_filesystems(wait);	/* Waitingly sync the filesystems */
	sync_inodes(wait);	/* Mappings, inodes and blockdevs, again. */
	if (!wait)
		printk("Emergency Sync complete\n");
	if (unlikely(laptop_mode))
		laptop_sync_completion();
}
Example #4
0
/*
 * writeback at least _min_pages, and keep writing until the amount of dirty
 * memory is less than the background threshold, or until we're all clean.
 */
static void background_writeout(unsigned long _min_pages)
{
	long min_pages = _min_pages;
	struct writeback_control wbc = {
		.bdi		= NULL,
		.sync_mode	= WB_SYNC_NONE,
		.older_than_this = NULL,
		.nr_to_write	= 0,
		.nonblocking	= 1,
		.range_cyclic	= 1,
	};

	for ( ; ; ) {
		long background_thresh;
		long dirty_thresh;

		get_dirty_limits(&background_thresh, &dirty_thresh, NULL, NULL);
		if (global_page_state(NR_FILE_DIRTY) +
			global_page_state(NR_UNSTABLE_NFS) < background_thresh
				&& min_pages <= 0)
			break;
		wbc.more_io = 0;
		wbc.encountered_congestion = 0;
		wbc.nr_to_write = MAX_WRITEBACK_PAGES;
		wbc.pages_skipped = 0;
		writeback_inodes(&wbc);
		min_pages -= MAX_WRITEBACK_PAGES - wbc.nr_to_write;
		if (wbc.nr_to_write > 0 || wbc.pages_skipped > 0) {
			/* Wrote less than expected */
			if (wbc.encountered_congestion || wbc.more_io)
				congestion_wait(WRITE, HZ/10);
			else
				break;
		}
	}
}

/*
 * Start writeback of `nr_pages' pages.  If `nr_pages' is zero, write back
 * the whole world.  Returns 0 if a pdflush thread was dispatched.  Returns
 * -1 if all pdflush threads were busy.
 */
int wakeup_pdflush(long nr_pages)
{
	if (nr_pages == 0)
		nr_pages = global_page_state(NR_FILE_DIRTY) +
				global_page_state(NR_UNSTABLE_NFS);
	return pdflush_operation(background_writeout, nr_pages);
}

static void wb_timer_fn(unsigned long unused);
static void laptop_timer_fn(unsigned long unused);

static DEFINE_TIMER(wb_timer, wb_timer_fn, 0, 0);
static DEFINE_TIMER(laptop_mode_wb_timer, laptop_timer_fn, 0, 0);

/*
 * Periodic writeback of "old" data.
 *
 * Define "old": the first time one of an inode's pages is dirtied, we mark the
 * dirtying-time in the inode's address_space.  So this periodic writeback code
 * just walks the superblock inode list, writing back any inodes which are
 * older than a specific point in time.
 *
 * Try to run once per dirty_writeback_interval.  But if a writeback event
 * takes longer than a dirty_writeback_interval interval, then leave a
 * one-second gap.
 *
 * older_than_this takes precedence over nr_to_write.  So we'll only write back
 * all dirty pages if they are all attached to "old" mappings.
 */
static void wb_kupdate(unsigned long arg)
{
	unsigned long oldest_jif;
	unsigned long start_jif;
	unsigned long next_jif;
	long nr_to_write;
	struct writeback_control wbc = {
		.bdi		= NULL,
		.sync_mode	= WB_SYNC_NONE,
		.older_than_this = &oldest_jif,
		.nr_to_write	= 0,
		.nonblocking	= 1,
		.for_kupdate	= 1,
		.range_cyclic	= 1,
	};

	sync_supers();

	oldest_jif = jiffies - dirty_expire_interval;
	start_jif = jiffies;
	next_jif = start_jif + dirty_writeback_interval;
	nr_to_write = global_page_state(NR_FILE_DIRTY) +
			global_page_state(NR_UNSTABLE_NFS) +
			(inodes_stat.nr_inodes - inodes_stat.nr_unused);
	while (nr_to_write > 0) {
		wbc.more_io = 0;
		wbc.encountered_congestion = 0;
		wbc.nr_to_write = MAX_WRITEBACK_PAGES;
		writeback_inodes(&wbc);
		if (wbc.nr_to_write > 0) {
			if (wbc.encountered_congestion || wbc.more_io)
				congestion_wait(WRITE, HZ/10);
			else
				break;	/* All the old data is written */
		}
		nr_to_write -= MAX_WRITEBACK_PAGES - wbc.nr_to_write;
	}
	if (time_before(next_jif, jiffies + HZ))
		next_jif = jiffies + HZ;
	if (dirty_writeback_interval)
		mod_timer(&wb_timer, next_jif);
}

/*
 * sysctl handler for /proc/sys/vm/dirty_writeback_centisecs
 */
int dirty_writeback_centisecs_handler(ctl_table *table, int write,
	struct file *file, void __user *buffer, size_t *length, loff_t *ppos)
{
	proc_dointvec_userhz_jiffies(table, write, file, buffer, length, ppos);
	if (dirty_writeback_interval)
		mod_timer(&wb_timer, jiffies + dirty_writeback_interval);
	else
		del_timer(&wb_timer);
	return 0;
}