LXR linux-old/fs/intermezzo/journal

   1/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2 * vim:expandtab:shiftwidth=8:tabstop=8:
   3 *
   4 *  Copyright (C) 1998 Peter J. Braam <braam@clusterfs.com>
   5 *
   6 *   This file is part of InterMezzo, http://www.inter-mezzo.org.
   7 *
   8 *   InterMezzo is free software; you can redistribute it and/or
   9 *   modify it under the terms of version 2 of the GNU General Public
  10 *   License as published by the Free Software Foundation.
  11 *
  12 *   InterMezzo is distributed in the hope that it will be useful,
  13 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 *   GNU General Public License for more details.
  16 *
  17 *   You should have received a copy of the GNU General Public License
  18 *   along with InterMezzo; if not, write to the Free Software
  19 *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20 */
  21
  22#include <linux/types.h>
  23#include <linux/kernel.h>
  24#include <linux/sched.h>
  25#include <linux/fs.h>
  26#include <linux/slab.h>
  27#include <linux/vmalloc.h>
  28#include <linux/stat.h>
  29#include <linux/errno.h>
  30#include <linux/locks.h>
  31#include <asm/segment.h>
  32#include <asm/uaccess.h>
  33#include <linux/string.h>
  34#include <linux/ext2_fs.h> 
  35
  36#include <linux/intermezzo_fs.h>
  37#include <linux/intermezzo_psdev.h>
  38
  39#if defined(CONFIG_EXT2_FS)
  40
  41/* EXT2 has no journalling, so these functions do nothing */
  42static loff_t presto_e2_freespace(struct presto_cache *cache,
  43                                         struct super_block *sb)
  44{
  45        unsigned long freebl = le32_to_cpu(sb->u.ext2_sb.s_es->s_free_blocks_count);
  46        unsigned long avail =   freebl - le32_to_cpu(sb->u.ext2_sb.s_es->s_r_blocks_count);
  47        return (avail <<  EXT2_BLOCK_SIZE_BITS(sb));
  48}
  49
  50/* start the filesystem journal operations */
  51static void *presto_e2_trans_start(struct presto_file_set *fset, struct inode *inode, int op)
  52{
  53        __u32 avail_kmlblocks;
  54
  55        if ( presto_no_journal(fset) ||
  56             strcmp(fset->fset_cache->cache_type, "ext2"))
  57                return NULL;
  58
  59        avail_kmlblocks = inode->i_sb->u.ext2_sb.s_es->s_free_blocks_count;
  60        
  61        if ( avail_kmlblocks < 3 ) {
  62                return ERR_PTR(-ENOSPC);
  63        }
  64        
  65        if (  (op != KML_OPCODE_UNLINK && op != KML_OPCODE_RMDIR)
  66              && avail_kmlblocks < 6 ) {
  67                return ERR_PTR(-ENOSPC);
  68        }            
  69        return (void *) 1;
  70}
  71
  72static void presto_e2_trans_commit(struct presto_file_set *fset, void *handle)
  73{
  74        do {} while (0);
  75}
  76
  77static int presto_e2_has_all_data(struct inode *inode)
  78{
  79        BUG();
  80        return 0;
  81}
  82
  83struct journal_ops presto_ext2_journal_ops = {
  84        tr_all_data: presto_e2_has_all_data,
  85        tr_avail: presto_e2_freespace,
  86        tr_start: presto_e2_trans_start,
  87        tr_commit: presto_e2_trans_commit,
  88        tr_journal_data: NULL
  89};
  90
  91#endif /* CONFIG_EXT2_FS */
  92