/*
* lcnalloc.h - Exports for NTFS kernel cluster (de)allocation. Part of the
* Linux-NTFS project.
*
* Copyright (c) 2004 Anton Altaparmakov
*
* This program/include file is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as published
* by the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program/include file is distributed in the hope that it will be
* useful, but WITHOUT ANY WARRANTY; without even the implied warranty
* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program (in the main directory of the Linux-NTFS
* distribution in the file COPYING); if not, write to the Free Software
* Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifndef _LINUX_NTFS_LCNALLOC_H
#define _LINUX_NTFS_LCNALLOC_H
#ifdef NTFS_RW
#include <linux/fs.h>
#include "types.h"
#include "runlist.h"
#include "volume.h"
typedef enum {
FIRST_ZONE = 0, /* For sanity checking. */
MFT_ZONE = 0, /* Allocate from $MFT zone. */
DATA_ZONE = 1, /* Allocate from $DATA zone. */
LAST_ZONE = 1, /* For sanity checking. */
} NTFS_CLUSTER_ALLOCATION_ZONES;
extern runlist_element *ntfs_cluster_alloc(ntfs_volume *vol,
const VCN start_vcn, const s64 count, const LCN start_lcn,
const NTFS_CLUSTER_ALLOCATION_ZONES zone);
extern s64 __ntfs_cluster_free(struct inode *vi, const VCN start_vcn,
s64 count, const BOOL write_locked, const BOOL is_rollback);
/**
* ntfs_cluster_free - free clusters on an ntfs volume
* @vi: vfs inode whose runlist describes the clusters to free
* @start_vcn: vcn in the runlist of @vi at which to start freeing clusters
* @count: number of clusters to free or -1 for all clusters
* @write_locked: true if the runlist is locked for writing
*
* Free @count clusters starting at the cluster @start_vcn in the runlist
* described by the vfs inode @vi.
*
* If @count is -1, all clusters from @start_vcn to the end of the runlist are
* deallocated. Thus, to completely free all clusters in a runlist, use
* @start_vcn = 0 and @count = -1.
*
* Note, ntfs_cluster_free() does not modify the runlist at all, so the caller
* has to deal with it later.
*
* Return the number of deallocated clusters (not counting sparse ones) on
* success and -errno on error.
*
* Locking: - The runlist described by @vi must be locked on entry and is
* locked on return. Note if the runlist is locked for reading the
* lock may be dropped and reacquired. Note the runlist may be
* modified when needed runlist fragments need to be mapped.
* - The volume lcn bitmap must be unlocked on entry and is unlocked
* on return.
* - This function takes the volume lcn bitmap lock for writing and
* modifies the bitmap contents.
*/
static inline s64 ntfs_cluster_free(struct inode *vi, const VCN start_vcn,
s64 count, const BOOL write_locked)
{
return __ntfs_cluster_free(vi, start_vcn, count, write_locked, FALSE);
}
extern int ntfs_cluster_free_from_rl_nolock(ntfs_volume *vol,
const runlist_element *rl);
/**
* ntfs_cluster_free_from_rl - free clusters from runlist
* @vol: mounted ntfs volume on which to free the clusters
* @rl: runlist describing the clusters to free
*
* Free all the clusters described by the runlist @rl on the volume @vol. In
* the case of an error being returned, at least some of the clusters were not
* freed.
*
* Return 0 on success and -errno on error.
*
* Locking: - This function takes the volume lcn bitmap lock for writing and
* modifies the bitmap contents.
* - The caller must have locked the runlist @rl for reading or
* writing.
*/
static inline int ntfs_cluster_free_from_rl(ntfs_volume *vol,
const runlist_element *rl)
{
int ret;
down_write(&vol->lcnbmp_lock);
ret = ntfs_cluster_free_from_rl_nolock(vol, rl);
up_write(&vol->lcnbmp_lock);
return ret;
}
#endif /* NTFS_RW */
#endif /* defined _LINUX_NTFS_LCNALLOC_H */
