linux/fs/xfs/xfs_iomap.h

105 lines
4.1 KiB
C

/*
* Copyright (c) 2003-2005 Silicon Graphics, Inc. All Rights Reserved.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of version 2 of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it would be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
*
* Further, this software is distributed without any warranty that it is
* free of the rightful claim of any third person regarding infringement
* or the like. Any license provided herein, whether implied or
* otherwise, applies only to this software file. Patent licenses, if
* any, provided herein do not apply to combinations of this program with
* other software, or any other product whatsoever.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write the Free Software Foundation, Inc., 59
* Temple Place - Suite 330, Boston MA 02111-1307, USA.
*
* Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
* Mountain View, CA 94043, or:
*
* http://www.sgi.com
*
* For further information regarding this notice, see:
*
* http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
*/
#ifndef __XFS_IOMAP_H__
#define __XFS_IOMAP_H__
#define IOMAP_DADDR_NULL ((xfs_daddr_t) (-1LL))
typedef enum { /* iomap_flags values */
IOMAP_EOF = 0x01, /* mapping contains EOF */
IOMAP_HOLE = 0x02, /* mapping covers a hole */
IOMAP_DELAY = 0x04, /* mapping covers delalloc region */
IOMAP_REALTIME = 0x10, /* mapping on the realtime device */
IOMAP_UNWRITTEN = 0x20, /* mapping covers allocated */
/* but uninitialized file data */
IOMAP_NEW = 0x40 /* just allocate */
} iomap_flags_t;
typedef enum {
/* base extent manipulation calls */
BMAPI_READ = (1 << 0), /* read extents */
BMAPI_WRITE = (1 << 1), /* create extents */
BMAPI_ALLOCATE = (1 << 2), /* delayed allocate to real extents */
BMAPI_UNWRITTEN = (1 << 3), /* unwritten extents to real extents */
/* modifiers */
BMAPI_IGNSTATE = (1 << 4), /* ignore unwritten state on read */
BMAPI_DIRECT = (1 << 5), /* direct instead of buffered write */
BMAPI_MMAP = (1 << 6), /* allocate for mmap write */
BMAPI_SYNC = (1 << 7), /* sync write to flush delalloc space */
BMAPI_TRYLOCK = (1 << 8), /* non-blocking request */
BMAPI_DEVICE = (1 << 9), /* we only want to know the device */
} bmapi_flags_t;
/*
* xfs_iomap_t: File system I/O map
*
* The iomap_bn field is expressed in 512-byte blocks, and is where the
* mapping starts on disk.
*
* The iomap_offset, iomap_bsize and iomap_delta fields are in bytes.
* iomap_offset is the offset of the mapping in the file itself.
* iomap_bsize is the size of the mapping, iomap_delta is the
* desired data's offset into the mapping, given the offset supplied
* to the file I/O map routine.
*
* When a request is made to read beyond the logical end of the object,
* iomap_size may be set to 0, but iomap_offset and iomap_length should be set
* to the actual amount of underlying storage that has been allocated, if any.
*/
typedef struct xfs_iomap {
xfs_daddr_t iomap_bn; /* first 512b blk of mapping */
xfs_buftarg_t *iomap_target;
xfs_off_t iomap_offset; /* offset of mapping, bytes */
xfs_off_t iomap_bsize; /* size of mapping, bytes */
size_t iomap_delta; /* offset into mapping, bytes */
iomap_flags_t iomap_flags;
} xfs_iomap_t;
struct xfs_iocore;
struct xfs_inode;
struct xfs_bmbt_irec;
extern int xfs_iomap(struct xfs_iocore *, xfs_off_t, ssize_t, int,
struct xfs_iomap *, int *);
extern int xfs_iomap_write_direct(struct xfs_inode *, xfs_off_t, size_t,
int, struct xfs_bmbt_irec *, int *, int);
extern int xfs_iomap_write_delay(struct xfs_inode *, xfs_off_t, size_t, int,
struct xfs_bmbt_irec *, int *);
extern int xfs_iomap_write_allocate(struct xfs_inode *, xfs_off_t, size_t,
struct xfs_bmbt_irec *, int *);
extern int xfs_iomap_write_unwritten(struct xfs_inode *, xfs_off_t, size_t);
#endif /* __XFS_IOMAP_H__*/