journal_reiserfs.c

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/*
 * Intermezzo. (C) 1998 Peter J. Braam
 * Intermezzo. (C) 2000 Red Hat, Inc.
 * Intermezzo. (C) 2000 Los Alamos National Laboratory
 * Intermezzo. (C) 2000 TurboLinux, Inc.
 * Intermezzo. (C) 2001 Mountain View Data, Inc.
 */

#include <linux/types.h>
#include <linux/param.h>
#include <linux/sched.h>
#include <linux/fs.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/stat.h>
#include <linux/errno.h>
#include <linux/smp_lock.h>
#include <linux/locks.h>
#include <asm/segment.h>
#include <asm/uaccess.h>
#include <linux/string.h>
#if 0
#if defined(CONFIG_REISERFS_FS) || defined(CONFIG_REISERFS_FS_MODULE)
#include <linux/reiserfs_fs.h>
#include <linux/reiserfs_fs_sb.h>
#include <linux/reiserfs_fs_i.h>
#endif

#include <linux/intermezzo_fs.h>
#include <linux/intermezzo_upcall.h>
#include <linux/intermezzo_psdev.h>
#include <linux/intermezzo_kml.h>
#if defined(CONFIG_REISERFS_FS) || defined(CONFIG_REISERFS_FS_MODULE)


static loff_t presto_reiserfs_freespace(struct presto_cache *cache,
                                         struct super_block *sb)
{
        struct reiserfs_super_block * rs = SB_DISK_SUPER_BLOCK (sb);
	loff_t avail;

        avail =   le32_to_cpu(rs->s_free_blocks) * 
		le16_to_cpu(rs->s_blocksize);
        return avail; 
}

/* start the filesystem journal operations */
static void *presto_reiserfs_trans_start(struct presto_file_set *fset, 
                                   struct inode *inode, 
                                   int op)
{
	int jblocks;
        __u32 avail_kmlblocks;
	struct reiserfs_transaction_handle *th ;

	PRESTO_ALLOC(th, struct reiserfs_transaction_handle *, sizeof(*th));
	if (!th) { 
		printk("presto: No memory for trans handle\n");
		return NULL;
	}

        avail_kmlblocks = presto_reiserfs_freespace(fset->fset_cache, 
						    inode->i_sb);
        if ( presto_no_journal(fset) ||
             strcmp(fset->fset_cache->cache_type, "reiserfs"))
		{
			CDEBUG(D_JOURNAL, "got cache_type \"%s\"\n",
			       fset->fset_cache->cache_type);
			return NULL;
		}

        if ( avail_kmlblocks < 3 ) {
                return ERR_PTR(-ENOSPC);
        }
        
        if (  (op != PRESTO_OP_UNLINK && op != PRESTO_OP_RMDIR)
              && avail_kmlblocks < 6 ) {
                return ERR_PTR(-ENOSPC);
        }            

	jblocks = 3 + JOURNAL_PER_BALANCE_CNT * 4;
        CDEBUG(D_JOURNAL, "creating journal handle (%d blocks)\n", jblocks);

	lock_kernel();
	//journal_begin(th, inode->i_sb, jblocks);
	unlock_kernel();
	return th; 
}

void presto_reiserfs_trans_commit(struct presto_file_set *fset, void *handle)
{
	int jblocks;
	jblocks = 3 + JOURNAL_PER_BALANCE_CNT * 4;
	
	lock_kernel();
	//journal_end(handle, fset->fset_cache->cache_sb, jblocks);
	unlock_kernel();
	PRESTO_FREE(handle, sizeof(struct reiserfs_transaction_handle));
}

void presto_reiserfs_journal_file_data(struct inode *inode)
{
#ifdef EXT3_JOURNAL_DATA_FL
        inode->u.ext3_i.i_flags |= EXT3_JOURNAL_DATA_FL;
#else
#warning You must have a facility to enable journaled writes for recovery!
#endif
}

struct journal_ops presto_reiserfs_journal_ops = {
        tr_avail: presto_reiserfs_freespace,
        tr_start:  presto_reiserfs_trans_start,
        tr_commit: presto_reiserfs_trans_commit,
        tr_journal_data: presto_reiserfs_journal_file_data
};

#endif
#endif