since unsigned, unused >= 0 is always true. Signed-off-by: Roel Kluin <12o3l@tiscali.nl> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
		
			
				
	
	
		
			908 lines
		
	
	
	
		
			22 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			908 lines
		
	
	
	
		
			22 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
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 * Copyright (C) 2004-2007 Red Hat, Inc.  All rights reserved.
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 *
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 * This copyrighted material is made available to anyone wishing to use,
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 * modify, copy, or redistribute it subject to the terms and conditions
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 * of the GNU General Public License version 2.
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 */
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#include <linux/sched.h>
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#include <linux/slab.h>
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#include <linux/spinlock.h>
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#include <linux/completion.h>
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#include <linux/buffer_head.h>
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#include <linux/gfs2_ondisk.h>
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#include <linux/crc32.h>
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#include <linux/lm_interface.h>
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#include <linux/delay.h>
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#include <linux/kthread.h>
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#include <linux/freezer.h>
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#include "gfs2.h"
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#include "incore.h"
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#include "bmap.h"
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#include "glock.h"
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#include "log.h"
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#include "lops.h"
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#include "meta_io.h"
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#include "util.h"
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#include "dir.h"
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#define PULL 1
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/**
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 * gfs2_struct2blk - compute stuff
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 * @sdp: the filesystem
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 * @nstruct: the number of structures
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 * @ssize: the size of the structures
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 *
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 * Compute the number of log descriptor blocks needed to hold a certain number
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 * of structures of a certain size.
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 *
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 * Returns: the number of blocks needed (minimum is always 1)
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 */
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unsigned int gfs2_struct2blk(struct gfs2_sbd *sdp, unsigned int nstruct,
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			     unsigned int ssize)
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{
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	unsigned int blks;
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	unsigned int first, second;
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	blks = 1;
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	first = (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_log_descriptor)) / ssize;
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	if (nstruct > first) {
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		second = (sdp->sd_sb.sb_bsize -
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			  sizeof(struct gfs2_meta_header)) / ssize;
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		blks += DIV_ROUND_UP(nstruct - first, second);
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	}
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	return blks;
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}
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/**
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 * gfs2_remove_from_ail - Remove an entry from the ail lists, updating counters
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 * @mapping: The associated mapping (maybe NULL)
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 * @bd: The gfs2_bufdata to remove
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 *
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 * The log lock _must_ be held when calling this function
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 *
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 */
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void gfs2_remove_from_ail(struct gfs2_bufdata *bd)
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{
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	bd->bd_ail = NULL;
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	list_del_init(&bd->bd_ail_st_list);
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	list_del_init(&bd->bd_ail_gl_list);
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	atomic_dec(&bd->bd_gl->gl_ail_count);
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	brelse(bd->bd_bh);
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}
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/**
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 * gfs2_ail1_start_one - Start I/O on a part of the AIL
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 * @sdp: the filesystem
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 * @tr: the part of the AIL
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 *
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 */
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static void gfs2_ail1_start_one(struct gfs2_sbd *sdp, struct gfs2_ail *ai)
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{
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	struct gfs2_bufdata *bd, *s;
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	struct buffer_head *bh;
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	int retry;
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	do {
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		retry = 0;
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		list_for_each_entry_safe_reverse(bd, s, &ai->ai_ail1_list,
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						 bd_ail_st_list) {
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			bh = bd->bd_bh;
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			gfs2_assert(sdp, bd->bd_ail == ai);
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			if (!buffer_busy(bh)) {
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				if (!buffer_uptodate(bh))
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					gfs2_io_error_bh(sdp, bh);
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				list_move(&bd->bd_ail_st_list, &ai->ai_ail2_list);
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				continue;
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			}
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			if (!buffer_dirty(bh))
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				continue;
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			list_move(&bd->bd_ail_st_list, &ai->ai_ail1_list);
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			get_bh(bh);
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			gfs2_log_unlock(sdp);
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			lock_buffer(bh);
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			if (test_clear_buffer_dirty(bh)) {
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				bh->b_end_io = end_buffer_write_sync;
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				submit_bh(WRITE, bh);
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			} else {
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				unlock_buffer(bh);
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				brelse(bh);
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			}
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			gfs2_log_lock(sdp);
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			retry = 1;
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			break;
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		}
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	} while (retry);
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}
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/**
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 * gfs2_ail1_empty_one - Check whether or not a trans in the AIL has been synced
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 * @sdp: the filesystem
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 * @ai: the AIL entry
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 *
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 */
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static int gfs2_ail1_empty_one(struct gfs2_sbd *sdp, struct gfs2_ail *ai, int flags)
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{
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	struct gfs2_bufdata *bd, *s;
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	struct buffer_head *bh;
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	list_for_each_entry_safe_reverse(bd, s, &ai->ai_ail1_list,
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					 bd_ail_st_list) {
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		bh = bd->bd_bh;
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		gfs2_assert(sdp, bd->bd_ail == ai);
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		if (buffer_busy(bh)) {
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			if (flags & DIO_ALL)
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				continue;
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			else
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				break;
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		}
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		if (!buffer_uptodate(bh))
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			gfs2_io_error_bh(sdp, bh);
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		list_move(&bd->bd_ail_st_list, &ai->ai_ail2_list);
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	}
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	return list_empty(&ai->ai_ail1_list);
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}
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static void gfs2_ail1_start(struct gfs2_sbd *sdp, int flags)
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{
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	struct list_head *head;
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	u64 sync_gen;
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	struct list_head *first;
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	struct gfs2_ail *first_ai, *ai, *tmp;
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	int done = 0;
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	gfs2_log_lock(sdp);
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	head = &sdp->sd_ail1_list;
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	if (list_empty(head)) {
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		gfs2_log_unlock(sdp);
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		return;
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	}
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	sync_gen = sdp->sd_ail_sync_gen++;
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	first = head->prev;
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	first_ai = list_entry(first, struct gfs2_ail, ai_list);
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	first_ai->ai_sync_gen = sync_gen;
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	gfs2_ail1_start_one(sdp, first_ai); /* This may drop log lock */
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	if (flags & DIO_ALL)
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		first = NULL;
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	while(!done) {
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		if (first && (head->prev != first ||
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			      gfs2_ail1_empty_one(sdp, first_ai, 0)))
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			break;
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		done = 1;
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		list_for_each_entry_safe_reverse(ai, tmp, head, ai_list) {
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			if (ai->ai_sync_gen >= sync_gen)
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				continue;
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			ai->ai_sync_gen = sync_gen;
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			gfs2_ail1_start_one(sdp, ai); /* This may drop log lock */
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			done = 0;
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			break;
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		}
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	}
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	gfs2_log_unlock(sdp);
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}
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static int gfs2_ail1_empty(struct gfs2_sbd *sdp, int flags)
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{
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	struct gfs2_ail *ai, *s;
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	int ret;
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	gfs2_log_lock(sdp);
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	list_for_each_entry_safe_reverse(ai, s, &sdp->sd_ail1_list, ai_list) {
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		if (gfs2_ail1_empty_one(sdp, ai, flags))
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			list_move(&ai->ai_list, &sdp->sd_ail2_list);
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		else if (!(flags & DIO_ALL))
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			break;
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	}
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	ret = list_empty(&sdp->sd_ail1_list);
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	gfs2_log_unlock(sdp);
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	return ret;
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}
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/**
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 * gfs2_ail2_empty_one - Check whether or not a trans in the AIL has been synced
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 * @sdp: the filesystem
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 * @ai: the AIL entry
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 *
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 */
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static void gfs2_ail2_empty_one(struct gfs2_sbd *sdp, struct gfs2_ail *ai)
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{
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	struct list_head *head = &ai->ai_ail2_list;
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	struct gfs2_bufdata *bd;
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	while (!list_empty(head)) {
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		bd = list_entry(head->prev, struct gfs2_bufdata,
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				bd_ail_st_list);
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		gfs2_assert(sdp, bd->bd_ail == ai);
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		gfs2_remove_from_ail(bd);
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	}
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}
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static void ail2_empty(struct gfs2_sbd *sdp, unsigned int new_tail)
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{
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	struct gfs2_ail *ai, *safe;
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	unsigned int old_tail = sdp->sd_log_tail;
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	int wrap = (new_tail < old_tail);
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	int a, b, rm;
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	gfs2_log_lock(sdp);
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	list_for_each_entry_safe(ai, safe, &sdp->sd_ail2_list, ai_list) {
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		a = (old_tail <= ai->ai_first);
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		b = (ai->ai_first < new_tail);
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		rm = (wrap) ? (a || b) : (a && b);
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		if (!rm)
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			continue;
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		gfs2_ail2_empty_one(sdp, ai);
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		list_del(&ai->ai_list);
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		gfs2_assert_warn(sdp, list_empty(&ai->ai_ail1_list));
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		gfs2_assert_warn(sdp, list_empty(&ai->ai_ail2_list));
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		kfree(ai);
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	}
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	gfs2_log_unlock(sdp);
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}
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/**
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 * gfs2_log_reserve - Make a log reservation
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 * @sdp: The GFS2 superblock
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 * @blks: The number of blocks to reserve
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 *
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 * Note that we never give out the last few blocks of the journal. Thats
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 * due to the fact that there is a small number of header blocks
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 * associated with each log flush. The exact number can't be known until
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 * flush time, so we ensure that we have just enough free blocks at all
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 * times to avoid running out during a log flush.
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 *
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 * Returns: errno
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 */
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int gfs2_log_reserve(struct gfs2_sbd *sdp, unsigned int blks)
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{
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	unsigned int try = 0;
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	unsigned reserved_blks = 6 * (4096 / sdp->sd_vfs->s_blocksize);
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	if (gfs2_assert_warn(sdp, blks) ||
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	    gfs2_assert_warn(sdp, blks <= sdp->sd_jdesc->jd_blocks))
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		return -EINVAL;
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	mutex_lock(&sdp->sd_log_reserve_mutex);
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	gfs2_log_lock(sdp);
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	while(atomic_read(&sdp->sd_log_blks_free) <= (blks + reserved_blks)) {
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		gfs2_log_unlock(sdp);
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		gfs2_ail1_empty(sdp, 0);
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		gfs2_log_flush(sdp, NULL);
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		if (try++)
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			gfs2_ail1_start(sdp, 0);
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		gfs2_log_lock(sdp);
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	}
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	atomic_sub(blks, &sdp->sd_log_blks_free);
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	gfs2_log_unlock(sdp);
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	mutex_unlock(&sdp->sd_log_reserve_mutex);
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	down_read(&sdp->sd_log_flush_lock);
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	return 0;
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}
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/**
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 * gfs2_log_release - Release a given number of log blocks
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 * @sdp: The GFS2 superblock
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 * @blks: The number of blocks
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 *
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 */
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void gfs2_log_release(struct gfs2_sbd *sdp, unsigned int blks)
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{
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	gfs2_log_lock(sdp);
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	atomic_add(blks, &sdp->sd_log_blks_free);
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	gfs2_assert_withdraw(sdp,
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			     atomic_read(&sdp->sd_log_blks_free) <= sdp->sd_jdesc->jd_blocks);
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	gfs2_log_unlock(sdp);
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	up_read(&sdp->sd_log_flush_lock);
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}
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static u64 log_bmap(struct gfs2_sbd *sdp, unsigned int lbn)
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{
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	struct gfs2_journal_extent *je;
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	list_for_each_entry(je, &sdp->sd_jdesc->extent_list, extent_list) {
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		if (lbn >= je->lblock && lbn < je->lblock + je->blocks)
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			return je->dblock + lbn - je->lblock;
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	}
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	return -1;
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}
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/**
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 * log_distance - Compute distance between two journal blocks
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 * @sdp: The GFS2 superblock
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 * @newer: The most recent journal block of the pair
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 * @older: The older journal block of the pair
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 *
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 *   Compute the distance (in the journal direction) between two
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 *   blocks in the journal
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 *
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 * Returns: the distance in blocks
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 */
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static inline unsigned int log_distance(struct gfs2_sbd *sdp, unsigned int newer,
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					unsigned int older)
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{
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	int dist;
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	dist = newer - older;
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	if (dist < 0)
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		dist += sdp->sd_jdesc->jd_blocks;
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	return dist;
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}
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/**
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 * calc_reserved - Calculate the number of blocks to reserve when
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 *                 refunding a transaction's unused buffers.
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 * @sdp: The GFS2 superblock
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 *
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 * This is complex.  We need to reserve room for all our currently used
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 * metadata buffers (e.g. normal file I/O rewriting file time stamps) and 
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 * all our journaled data buffers for journaled files (e.g. files in the 
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 * meta_fs like rindex, or files for which chattr +j was done.)
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 * If we don't reserve enough space, gfs2_log_refund and gfs2_log_flush
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 * will count it as free space (sd_log_blks_free) and corruption will follow.
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 *
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 * We can have metadata bufs and jdata bufs in the same journal.  So each
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 * type gets its own log header, for which we need to reserve a block.
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 * In fact, each type has the potential for needing more than one header 
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 * in cases where we have more buffers than will fit on a journal page.
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 * Metadata journal entries take up half the space of journaled buffer entries.
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 * Thus, metadata entries have buf_limit (502) and journaled buffers have
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 * databuf_limit (251) before they cause a wrap around.
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 *
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 * Also, we need to reserve blocks for revoke journal entries and one for an
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 * overall header for the lot.
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 *
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 * Returns: the number of blocks reserved
 | 
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 */
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static unsigned int calc_reserved(struct gfs2_sbd *sdp)
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{
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	unsigned int reserved = 0;
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	unsigned int mbuf_limit, metabufhdrs_needed;
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						|
	unsigned int dbuf_limit, databufhdrs_needed;
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	unsigned int revokes = 0;
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	mbuf_limit = buf_limit(sdp);
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	metabufhdrs_needed = (sdp->sd_log_commited_buf +
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			      (mbuf_limit - 1)) / mbuf_limit;
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	dbuf_limit = databuf_limit(sdp);
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	databufhdrs_needed = (sdp->sd_log_commited_databuf +
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			      (dbuf_limit - 1)) / dbuf_limit;
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	if (sdp->sd_log_commited_revoke)
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		revokes = gfs2_struct2blk(sdp, sdp->sd_log_commited_revoke,
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					  sizeof(u64));
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	reserved = sdp->sd_log_commited_buf + metabufhdrs_needed +
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		sdp->sd_log_commited_databuf + databufhdrs_needed +
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		revokes;
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	/* One for the overall header */
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						|
	if (reserved)
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		reserved++;
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	return reserved;
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}
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 | 
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static unsigned int current_tail(struct gfs2_sbd *sdp)
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{
 | 
						|
	struct gfs2_ail *ai;
 | 
						|
	unsigned int tail;
 | 
						|
 | 
						|
	gfs2_log_lock(sdp);
 | 
						|
 | 
						|
	if (list_empty(&sdp->sd_ail1_list)) {
 | 
						|
		tail = sdp->sd_log_head;
 | 
						|
	} else {
 | 
						|
		ai = list_entry(sdp->sd_ail1_list.prev, struct gfs2_ail, ai_list);
 | 
						|
		tail = ai->ai_first;
 | 
						|
	}
 | 
						|
 | 
						|
	gfs2_log_unlock(sdp);
 | 
						|
 | 
						|
	return tail;
 | 
						|
}
 | 
						|
 | 
						|
void gfs2_log_incr_head(struct gfs2_sbd *sdp)
 | 
						|
{
 | 
						|
	if (sdp->sd_log_flush_head == sdp->sd_log_tail)
 | 
						|
		BUG_ON(sdp->sd_log_flush_head != sdp->sd_log_head);
 | 
						|
 | 
						|
	if (++sdp->sd_log_flush_head == sdp->sd_jdesc->jd_blocks) {
 | 
						|
		sdp->sd_log_flush_head = 0;
 | 
						|
		sdp->sd_log_flush_wrapped = 1;
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * gfs2_log_write_endio - End of I/O for a log buffer
 | 
						|
 * @bh: The buffer head
 | 
						|
 * @uptodate: I/O Status
 | 
						|
 *
 | 
						|
 */
 | 
						|
 | 
						|
static void gfs2_log_write_endio(struct buffer_head *bh, int uptodate)
 | 
						|
{
 | 
						|
	struct gfs2_sbd *sdp = bh->b_private;
 | 
						|
	bh->b_private = NULL;
 | 
						|
 | 
						|
	end_buffer_write_sync(bh, uptodate);
 | 
						|
	if (atomic_dec_and_test(&sdp->sd_log_in_flight))
 | 
						|
		wake_up(&sdp->sd_log_flush_wait);
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * gfs2_log_get_buf - Get and initialize a buffer to use for log control data
 | 
						|
 * @sdp: The GFS2 superblock
 | 
						|
 *
 | 
						|
 * Returns: the buffer_head
 | 
						|
 */
 | 
						|
 | 
						|
struct buffer_head *gfs2_log_get_buf(struct gfs2_sbd *sdp)
 | 
						|
{
 | 
						|
	u64 blkno = log_bmap(sdp, sdp->sd_log_flush_head);
 | 
						|
	struct buffer_head *bh;
 | 
						|
 | 
						|
	bh = sb_getblk(sdp->sd_vfs, blkno);
 | 
						|
	lock_buffer(bh);
 | 
						|
	memset(bh->b_data, 0, bh->b_size);
 | 
						|
	set_buffer_uptodate(bh);
 | 
						|
	clear_buffer_dirty(bh);
 | 
						|
	gfs2_log_incr_head(sdp);
 | 
						|
	atomic_inc(&sdp->sd_log_in_flight);
 | 
						|
	bh->b_private = sdp;
 | 
						|
	bh->b_end_io = gfs2_log_write_endio;
 | 
						|
 | 
						|
	return bh;
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * gfs2_fake_write_endio - 
 | 
						|
 * @bh: The buffer head
 | 
						|
 * @uptodate: The I/O Status
 | 
						|
 *
 | 
						|
 */
 | 
						|
 | 
						|
static void gfs2_fake_write_endio(struct buffer_head *bh, int uptodate)
 | 
						|
{
 | 
						|
	struct buffer_head *real_bh = bh->b_private;
 | 
						|
	struct gfs2_bufdata *bd = real_bh->b_private;
 | 
						|
	struct gfs2_sbd *sdp = bd->bd_gl->gl_sbd;
 | 
						|
 | 
						|
	end_buffer_write_sync(bh, uptodate);
 | 
						|
	free_buffer_head(bh);
 | 
						|
	unlock_buffer(real_bh);
 | 
						|
	brelse(real_bh);
 | 
						|
	if (atomic_dec_and_test(&sdp->sd_log_in_flight))
 | 
						|
		wake_up(&sdp->sd_log_flush_wait);
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * gfs2_log_fake_buf - Build a fake buffer head to write metadata buffer to log
 | 
						|
 * @sdp: the filesystem
 | 
						|
 * @data: the data the buffer_head should point to
 | 
						|
 *
 | 
						|
 * Returns: the log buffer descriptor
 | 
						|
 */
 | 
						|
 | 
						|
struct buffer_head *gfs2_log_fake_buf(struct gfs2_sbd *sdp,
 | 
						|
				      struct buffer_head *real)
 | 
						|
{
 | 
						|
	u64 blkno = log_bmap(sdp, sdp->sd_log_flush_head);
 | 
						|
	struct buffer_head *bh;
 | 
						|
 | 
						|
	bh = alloc_buffer_head(GFP_NOFS | __GFP_NOFAIL);
 | 
						|
	atomic_set(&bh->b_count, 1);
 | 
						|
	bh->b_state = (1 << BH_Mapped) | (1 << BH_Uptodate) | (1 << BH_Lock);
 | 
						|
	set_bh_page(bh, real->b_page, bh_offset(real));
 | 
						|
	bh->b_blocknr = blkno;
 | 
						|
	bh->b_size = sdp->sd_sb.sb_bsize;
 | 
						|
	bh->b_bdev = sdp->sd_vfs->s_bdev;
 | 
						|
	bh->b_private = real;
 | 
						|
	bh->b_end_io = gfs2_fake_write_endio;
 | 
						|
 | 
						|
	gfs2_log_incr_head(sdp);
 | 
						|
	atomic_inc(&sdp->sd_log_in_flight);
 | 
						|
 | 
						|
	return bh;
 | 
						|
}
 | 
						|
 | 
						|
static void log_pull_tail(struct gfs2_sbd *sdp, unsigned int new_tail)
 | 
						|
{
 | 
						|
	unsigned int dist = log_distance(sdp, new_tail, sdp->sd_log_tail);
 | 
						|
 | 
						|
	ail2_empty(sdp, new_tail);
 | 
						|
 | 
						|
	gfs2_log_lock(sdp);
 | 
						|
	atomic_add(dist, &sdp->sd_log_blks_free);
 | 
						|
	gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <= sdp->sd_jdesc->jd_blocks);
 | 
						|
	gfs2_log_unlock(sdp);
 | 
						|
 | 
						|
	sdp->sd_log_tail = new_tail;
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * log_write_header - Get and initialize a journal header buffer
 | 
						|
 * @sdp: The GFS2 superblock
 | 
						|
 *
 | 
						|
 * Returns: the initialized log buffer descriptor
 | 
						|
 */
 | 
						|
 | 
						|
static void log_write_header(struct gfs2_sbd *sdp, u32 flags, int pull)
 | 
						|
{
 | 
						|
	u64 blkno = log_bmap(sdp, sdp->sd_log_flush_head);
 | 
						|
	struct buffer_head *bh;
 | 
						|
	struct gfs2_log_header *lh;
 | 
						|
	unsigned int tail;
 | 
						|
	u32 hash;
 | 
						|
 | 
						|
	bh = sb_getblk(sdp->sd_vfs, blkno);
 | 
						|
	lock_buffer(bh);
 | 
						|
	memset(bh->b_data, 0, bh->b_size);
 | 
						|
	set_buffer_uptodate(bh);
 | 
						|
	clear_buffer_dirty(bh);
 | 
						|
	unlock_buffer(bh);
 | 
						|
 | 
						|
	gfs2_ail1_empty(sdp, 0);
 | 
						|
	tail = current_tail(sdp);
 | 
						|
 | 
						|
	lh = (struct gfs2_log_header *)bh->b_data;
 | 
						|
	memset(lh, 0, sizeof(struct gfs2_log_header));
 | 
						|
	lh->lh_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
 | 
						|
	lh->lh_header.mh_type = cpu_to_be32(GFS2_METATYPE_LH);
 | 
						|
	lh->lh_header.mh_format = cpu_to_be32(GFS2_FORMAT_LH);
 | 
						|
	lh->lh_sequence = cpu_to_be64(sdp->sd_log_sequence++);
 | 
						|
	lh->lh_flags = cpu_to_be32(flags);
 | 
						|
	lh->lh_tail = cpu_to_be32(tail);
 | 
						|
	lh->lh_blkno = cpu_to_be32(sdp->sd_log_flush_head);
 | 
						|
	hash = gfs2_disk_hash(bh->b_data, sizeof(struct gfs2_log_header));
 | 
						|
	lh->lh_hash = cpu_to_be32(hash);
 | 
						|
 | 
						|
	set_buffer_dirty(bh);
 | 
						|
	if (sync_dirty_buffer(bh))
 | 
						|
		gfs2_io_error_bh(sdp, bh);
 | 
						|
	brelse(bh);
 | 
						|
 | 
						|
	if (sdp->sd_log_tail != tail)
 | 
						|
		log_pull_tail(sdp, tail);
 | 
						|
	else
 | 
						|
		gfs2_assert_withdraw(sdp, !pull);
 | 
						|
 | 
						|
	sdp->sd_log_idle = (tail == sdp->sd_log_flush_head);
 | 
						|
	gfs2_log_incr_head(sdp);
 | 
						|
}
 | 
						|
 | 
						|
static void log_flush_commit(struct gfs2_sbd *sdp)
 | 
						|
{
 | 
						|
	DEFINE_WAIT(wait);
 | 
						|
 | 
						|
	if (atomic_read(&sdp->sd_log_in_flight)) {
 | 
						|
		do {
 | 
						|
			prepare_to_wait(&sdp->sd_log_flush_wait, &wait,
 | 
						|
					TASK_UNINTERRUPTIBLE);
 | 
						|
			if (atomic_read(&sdp->sd_log_in_flight))
 | 
						|
				io_schedule();
 | 
						|
		} while(atomic_read(&sdp->sd_log_in_flight));
 | 
						|
		finish_wait(&sdp->sd_log_flush_wait, &wait);
 | 
						|
	}
 | 
						|
 | 
						|
	log_write_header(sdp, 0, 0);
 | 
						|
}
 | 
						|
 | 
						|
static void gfs2_ordered_write(struct gfs2_sbd *sdp)
 | 
						|
{
 | 
						|
	struct gfs2_bufdata *bd;
 | 
						|
	struct buffer_head *bh;
 | 
						|
	LIST_HEAD(written);
 | 
						|
 | 
						|
	gfs2_log_lock(sdp);
 | 
						|
	while (!list_empty(&sdp->sd_log_le_ordered)) {
 | 
						|
		bd = list_entry(sdp->sd_log_le_ordered.next, struct gfs2_bufdata, bd_le.le_list);
 | 
						|
		list_move(&bd->bd_le.le_list, &written);
 | 
						|
		bh = bd->bd_bh;
 | 
						|
		if (!buffer_dirty(bh))
 | 
						|
			continue;
 | 
						|
		get_bh(bh);
 | 
						|
		gfs2_log_unlock(sdp);
 | 
						|
		lock_buffer(bh);
 | 
						|
		if (buffer_mapped(bh) && test_clear_buffer_dirty(bh)) {
 | 
						|
			bh->b_end_io = end_buffer_write_sync;
 | 
						|
			submit_bh(WRITE, bh);
 | 
						|
		} else {
 | 
						|
			unlock_buffer(bh);
 | 
						|
			brelse(bh);
 | 
						|
		}
 | 
						|
		gfs2_log_lock(sdp);
 | 
						|
	}
 | 
						|
	list_splice(&written, &sdp->sd_log_le_ordered);
 | 
						|
	gfs2_log_unlock(sdp);
 | 
						|
}
 | 
						|
 | 
						|
static void gfs2_ordered_wait(struct gfs2_sbd *sdp)
 | 
						|
{
 | 
						|
	struct gfs2_bufdata *bd;
 | 
						|
	struct buffer_head *bh;
 | 
						|
 | 
						|
	gfs2_log_lock(sdp);
 | 
						|
	while (!list_empty(&sdp->sd_log_le_ordered)) {
 | 
						|
		bd = list_entry(sdp->sd_log_le_ordered.prev, struct gfs2_bufdata, bd_le.le_list);
 | 
						|
		bh = bd->bd_bh;
 | 
						|
		if (buffer_locked(bh)) {
 | 
						|
			get_bh(bh);
 | 
						|
			gfs2_log_unlock(sdp);
 | 
						|
			wait_on_buffer(bh);
 | 
						|
			brelse(bh);
 | 
						|
			gfs2_log_lock(sdp);
 | 
						|
			continue;
 | 
						|
		}
 | 
						|
		list_del_init(&bd->bd_le.le_list);
 | 
						|
	}
 | 
						|
	gfs2_log_unlock(sdp);
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * gfs2_log_flush - flush incore transaction(s)
 | 
						|
 * @sdp: the filesystem
 | 
						|
 * @gl: The glock structure to flush.  If NULL, flush the whole incore log
 | 
						|
 *
 | 
						|
 */
 | 
						|
 | 
						|
void __gfs2_log_flush(struct gfs2_sbd *sdp, struct gfs2_glock *gl)
 | 
						|
{
 | 
						|
	struct gfs2_ail *ai;
 | 
						|
 | 
						|
	down_write(&sdp->sd_log_flush_lock);
 | 
						|
 | 
						|
	/* Log might have been flushed while we waited for the flush lock */
 | 
						|
	if (gl && !test_bit(GLF_LFLUSH, &gl->gl_flags)) {
 | 
						|
		up_write(&sdp->sd_log_flush_lock);
 | 
						|
		return;
 | 
						|
	}
 | 
						|
 | 
						|
	ai = kzalloc(sizeof(struct gfs2_ail), GFP_NOFS | __GFP_NOFAIL);
 | 
						|
	INIT_LIST_HEAD(&ai->ai_ail1_list);
 | 
						|
	INIT_LIST_HEAD(&ai->ai_ail2_list);
 | 
						|
 | 
						|
	if (sdp->sd_log_num_buf != sdp->sd_log_commited_buf) {
 | 
						|
		printk(KERN_INFO "GFS2: log buf %u %u\n", sdp->sd_log_num_buf,
 | 
						|
		       sdp->sd_log_commited_buf);
 | 
						|
		gfs2_assert_withdraw(sdp, 0);
 | 
						|
	}
 | 
						|
	if (sdp->sd_log_num_databuf != sdp->sd_log_commited_databuf) {
 | 
						|
		printk(KERN_INFO "GFS2: log databuf %u %u\n",
 | 
						|
		       sdp->sd_log_num_databuf, sdp->sd_log_commited_databuf);
 | 
						|
		gfs2_assert_withdraw(sdp, 0);
 | 
						|
	}
 | 
						|
	gfs2_assert_withdraw(sdp,
 | 
						|
			sdp->sd_log_num_revoke == sdp->sd_log_commited_revoke);
 | 
						|
 | 
						|
	sdp->sd_log_flush_head = sdp->sd_log_head;
 | 
						|
	sdp->sd_log_flush_wrapped = 0;
 | 
						|
	ai->ai_first = sdp->sd_log_flush_head;
 | 
						|
 | 
						|
	gfs2_ordered_write(sdp);
 | 
						|
	lops_before_commit(sdp);
 | 
						|
	gfs2_ordered_wait(sdp);
 | 
						|
 | 
						|
	if (sdp->sd_log_head != sdp->sd_log_flush_head)
 | 
						|
		log_flush_commit(sdp);
 | 
						|
	else if (sdp->sd_log_tail != current_tail(sdp) && !sdp->sd_log_idle){
 | 
						|
		gfs2_log_lock(sdp);
 | 
						|
		atomic_dec(&sdp->sd_log_blks_free); /* Adjust for unreserved buffer */
 | 
						|
		gfs2_log_unlock(sdp);
 | 
						|
		log_write_header(sdp, 0, PULL);
 | 
						|
	}
 | 
						|
	lops_after_commit(sdp, ai);
 | 
						|
 | 
						|
	gfs2_log_lock(sdp);
 | 
						|
	sdp->sd_log_head = sdp->sd_log_flush_head;
 | 
						|
	sdp->sd_log_blks_reserved = 0;
 | 
						|
	sdp->sd_log_commited_buf = 0;
 | 
						|
	sdp->sd_log_commited_databuf = 0;
 | 
						|
	sdp->sd_log_commited_revoke = 0;
 | 
						|
 | 
						|
	if (!list_empty(&ai->ai_ail1_list)) {
 | 
						|
		list_add(&ai->ai_list, &sdp->sd_ail1_list);
 | 
						|
		ai = NULL;
 | 
						|
	}
 | 
						|
	gfs2_log_unlock(sdp);
 | 
						|
 | 
						|
	sdp->sd_vfs->s_dirt = 0;
 | 
						|
	up_write(&sdp->sd_log_flush_lock);
 | 
						|
 | 
						|
	kfree(ai);
 | 
						|
}
 | 
						|
 | 
						|
static void log_refund(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
 | 
						|
{
 | 
						|
	unsigned int reserved;
 | 
						|
	unsigned int unused;
 | 
						|
 | 
						|
	gfs2_log_lock(sdp);
 | 
						|
 | 
						|
	sdp->sd_log_commited_buf += tr->tr_num_buf_new - tr->tr_num_buf_rm;
 | 
						|
	sdp->sd_log_commited_databuf += tr->tr_num_databuf_new -
 | 
						|
		tr->tr_num_databuf_rm;
 | 
						|
	gfs2_assert_withdraw(sdp, (((int)sdp->sd_log_commited_buf) >= 0) ||
 | 
						|
			     (((int)sdp->sd_log_commited_databuf) >= 0));
 | 
						|
	sdp->sd_log_commited_revoke += tr->tr_num_revoke - tr->tr_num_revoke_rm;
 | 
						|
	gfs2_assert_withdraw(sdp, ((int)sdp->sd_log_commited_revoke) >= 0);
 | 
						|
	reserved = calc_reserved(sdp);
 | 
						|
	gfs2_assert_withdraw(sdp, sdp->sd_log_blks_reserved + tr->tr_reserved >= reserved);
 | 
						|
	unused = sdp->sd_log_blks_reserved - reserved + tr->tr_reserved;
 | 
						|
	atomic_add(unused, &sdp->sd_log_blks_free);
 | 
						|
	gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <=
 | 
						|
			     sdp->sd_jdesc->jd_blocks);
 | 
						|
	sdp->sd_log_blks_reserved = reserved;
 | 
						|
 | 
						|
	gfs2_log_unlock(sdp);
 | 
						|
}
 | 
						|
 | 
						|
static void buf_lo_incore_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
 | 
						|
{
 | 
						|
	struct list_head *head = &tr->tr_list_buf;
 | 
						|
	struct gfs2_bufdata *bd;
 | 
						|
 | 
						|
	gfs2_log_lock(sdp);
 | 
						|
	while (!list_empty(head)) {
 | 
						|
		bd = list_entry(head->next, struct gfs2_bufdata, bd_list_tr);
 | 
						|
		list_del_init(&bd->bd_list_tr);
 | 
						|
		tr->tr_num_buf--;
 | 
						|
	}
 | 
						|
	gfs2_log_unlock(sdp);
 | 
						|
	gfs2_assert_warn(sdp, !tr->tr_num_buf);
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * gfs2_log_commit - Commit a transaction to the log
 | 
						|
 * @sdp: the filesystem
 | 
						|
 * @tr: the transaction
 | 
						|
 *
 | 
						|
 * Returns: errno
 | 
						|
 */
 | 
						|
 | 
						|
void gfs2_log_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
 | 
						|
{
 | 
						|
	log_refund(sdp, tr);
 | 
						|
	buf_lo_incore_commit(sdp, tr);
 | 
						|
 | 
						|
	sdp->sd_vfs->s_dirt = 1;
 | 
						|
	up_read(&sdp->sd_log_flush_lock);
 | 
						|
 | 
						|
	gfs2_log_lock(sdp);
 | 
						|
	if (sdp->sd_log_num_buf > gfs2_tune_get(sdp, gt_incore_log_blocks))
 | 
						|
		wake_up_process(sdp->sd_logd_process);
 | 
						|
	gfs2_log_unlock(sdp);
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * gfs2_log_shutdown - write a shutdown header into a journal
 | 
						|
 * @sdp: the filesystem
 | 
						|
 *
 | 
						|
 */
 | 
						|
 | 
						|
void gfs2_log_shutdown(struct gfs2_sbd *sdp)
 | 
						|
{
 | 
						|
	down_write(&sdp->sd_log_flush_lock);
 | 
						|
 | 
						|
	gfs2_assert_withdraw(sdp, !sdp->sd_log_blks_reserved);
 | 
						|
	gfs2_assert_withdraw(sdp, !sdp->sd_log_num_buf);
 | 
						|
	gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke);
 | 
						|
	gfs2_assert_withdraw(sdp, !sdp->sd_log_num_rg);
 | 
						|
	gfs2_assert_withdraw(sdp, !sdp->sd_log_num_databuf);
 | 
						|
	gfs2_assert_withdraw(sdp, list_empty(&sdp->sd_ail1_list));
 | 
						|
 | 
						|
	sdp->sd_log_flush_head = sdp->sd_log_head;
 | 
						|
	sdp->sd_log_flush_wrapped = 0;
 | 
						|
 | 
						|
	log_write_header(sdp, GFS2_LOG_HEAD_UNMOUNT,
 | 
						|
			 (sdp->sd_log_tail == current_tail(sdp)) ? 0 : PULL);
 | 
						|
 | 
						|
	gfs2_assert_warn(sdp, atomic_read(&sdp->sd_log_blks_free) == sdp->sd_jdesc->jd_blocks);
 | 
						|
	gfs2_assert_warn(sdp, sdp->sd_log_head == sdp->sd_log_tail);
 | 
						|
	gfs2_assert_warn(sdp, list_empty(&sdp->sd_ail2_list));
 | 
						|
 | 
						|
	sdp->sd_log_head = sdp->sd_log_flush_head;
 | 
						|
	sdp->sd_log_tail = sdp->sd_log_head;
 | 
						|
 | 
						|
	up_write(&sdp->sd_log_flush_lock);
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/**
 | 
						|
 * gfs2_meta_syncfs - sync all the buffers in a filesystem
 | 
						|
 * @sdp: the filesystem
 | 
						|
 *
 | 
						|
 */
 | 
						|
 | 
						|
void gfs2_meta_syncfs(struct gfs2_sbd *sdp)
 | 
						|
{
 | 
						|
	gfs2_log_flush(sdp, NULL);
 | 
						|
	for (;;) {
 | 
						|
		gfs2_ail1_start(sdp, DIO_ALL);
 | 
						|
		if (gfs2_ail1_empty(sdp, DIO_ALL))
 | 
						|
			break;
 | 
						|
		msleep(10);
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/**
 | 
						|
 * 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 = data;
 | 
						|
	unsigned long t;
 | 
						|
	int need_flush;
 | 
						|
 | 
						|
	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);
 | 
						|
		gfs2_log_lock(sdp);
 | 
						|
		need_flush = sdp->sd_log_num_buf > gfs2_tune_get(sdp, gt_incore_log_blocks);
 | 
						|
		gfs2_log_unlock(sdp);
 | 
						|
		if (need_flush || time_after_eq(jiffies, t)) {
 | 
						|
			gfs2_log_flush(sdp, NULL);
 | 
						|
			sdp->sd_log_flush_time = jiffies;
 | 
						|
		}
 | 
						|
 | 
						|
		t = gfs2_tune_get(sdp, gt_logd_secs) * HZ;
 | 
						|
		if (freezing(current))
 | 
						|
			refrigerator();
 | 
						|
		schedule_timeout_interruptible(t);
 | 
						|
	}
 | 
						|
 | 
						|
	return 0;
 | 
						|
}
 | 
						|
 |