fs/nfs/blocklayout/blocklayout.h

/*
 *  linux/fs/nfs/blocklayout/blocklayout.h
 *
 *  Module for the NFSv4.1 pNFS block layout driver.
 *
 *  Copyright (c) 2006 The Regents of the University of Michigan.
 *  All rights reserved.
 *
 *  Andy Adamson <andros@citi.umich.edu>
 *  Fred Isaman <iisaman@umich.edu>
 *
 * permission is granted to use, copy, create derivative works and
 * redistribute this software and such derivative works for any purpose,
 * so long as the name of the university of michigan is not used in
 * any advertising or publicity pertaining to the use or distribution
 * of this software without specific, written prior authorization.  if
 * the above copyright notice or any other identification of the
 * university of michigan is included in any copy of any portion of
 * this software, then the disclaimer below must also be included.
 *
 * this software is provided as is, without representation from the
 * university of michigan as to its fitness for any purpose, and without
 * warranty by the university of michigan of any kind, either express
 * or implied, including without limitation the implied warranties of
 * merchantability and fitness for a particular purpose.  the regents
 * of the university of michigan shall not be liable for any damages,
 * including special, indirect, incidental, or consequential damages,
 * with respect to any claim arising out or in connection with the use
 * of the software, even if it has been or is hereafter advised of the
 * possibility of such damages.
 */
#ifndef FS_NFS_NFS4BLOCKLAYOUT_H
#define FS_NFS_NFS4BLOCKLAYOUT_H

#include <linux/device-mapper.h>
#include <linux/nfs_fs.h>
#include "../pnfs.h"

enum exstate4 {
	PNFS_BLOCK_READWRITE_DATA	= 0,
	PNFS_BLOCK_READ_DATA		= 1,
	PNFS_BLOCK_INVALID_DATA		= 2, /* mapped, but data is invalid */
	PNFS_BLOCK_NONE_DATA		= 3  /* unmapped, it's a hole */
};

struct pnfs_inval_markings {
	/* STUB */
};

/* sector_t fields are all in 512-byte sectors */
struct pnfs_block_extent {
	struct kref	be_refcnt;
	struct list_head be_node;	/* link into lseg list */
	struct nfs4_deviceid be_devid;  /* FIXME: could use device cache instead */
	struct block_device *be_mdev;
	sector_t	be_f_offset;	/* the starting offset in the file */
	sector_t	be_length;	/* the size of the extent */
	sector_t	be_v_offset;	/* the starting offset in the volume */
	enum exstate4	be_state;	/* the state of this extent */
	struct pnfs_inval_markings *be_inval; /* tracks INVAL->RW transition */
};

static inline void
BL_INIT_INVAL_MARKS(struct pnfs_inval_markings *marks, sector_t blocksize)
{
	/* STUB */
}

enum extentclass4 {
	RW_EXTENT       = 0, /* READWRTE and INVAL */
	RO_EXTENT       = 1, /* READ and NONE */
	EXTENT_LISTS    = 2,
};

struct pnfs_block_layout {
	struct pnfs_layout_hdr bl_layout;
	struct pnfs_inval_markings bl_inval; /* tracks INVAL->RW transition */
	spinlock_t		bl_ext_lock;   /* Protects list manipulation */
	struct list_head	bl_extents[EXTENT_LISTS]; /* R and RW extents */
	struct list_head	bl_commit;	/* Needs layout commit */
	struct list_head	bl_committing;	/* Layout committing */
	unsigned int		bl_count;	/* entries in bl_commit */
	sector_t		bl_blocksize;  /* Server blocksize in sectors */
};

static inline struct pnfs_block_layout *BLK_LO2EXT(struct pnfs_layout_hdr *lo)
{
	return container_of(lo, struct pnfs_block_layout, bl_layout);
}

void bl_put_extent(struct pnfs_block_extent *be);
#endif /* FS_NFS_NFS4BLOCKLAYOUT_H */