[mirror_ubuntu-zesty-kernel.git] / fs / xfs / xfs_buf.h

/*
 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
 * All Rights Reserved.
 *
 * This program 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.
 *
 * 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.  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; if not, write the Free Software Foundation,
 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
#ifndef __XFS_BUF_H__
#define __XFS_BUF_H__

#include <linux/list.h>
#include <linux/types.h>
#include <linux/spinlock.h>
#include <linux/mm.h>
#include <linux/fs.h>
#include <linux/buffer_head.h>
#include <linux/uio.h>

/*
 *	Base types
 */

#define XFS_BUF_DADDR_NULL	((xfs_daddr_t) (-1LL))

typedef enum {
	XBRW_READ = 1,			/* transfer into target memory */
	XBRW_WRITE = 2,			/* transfer from target memory */
	XBRW_ZERO = 3,			/* Zero target memory */
} xfs_buf_rw_t;

#define XBF_READ	(1 << 0) /* buffer intended for reading from device */
#define XBF_WRITE	(1 << 1) /* buffer intended for writing to device */
#define XBF_READ_AHEAD	(1 << 2) /* asynchronous read-ahead */
#define XBF_MAPPED	(1 << 3) /* buffer mapped (b_addr valid) */
#define XBF_ASYNC	(1 << 4) /* initiator will not wait for completion */
#define XBF_DONE	(1 << 5) /* all pages in the buffer uptodate */
#define XBF_STALE	(1 << 6) /* buffer has been staled, do not find it */

/* I/O hints for the BIO layer */
#define XBF_SYNCIO	(1 << 10)/* treat this buffer as synchronous I/O */
#define XBF_FUA		(1 << 11)/* force cache write through mode */
#define XBF_FLUSH	(1 << 12)/* flush the disk cache before a write */

/* flags used only as arguments to access routines */
#define XBF_TRYLOCK	(1 << 16)/* lock requested, but do not wait */

/* flags used only internally */
#define _XBF_PAGES	(1 << 20)/* backed by refcounted pages */
#define _XBF_KMEM	(1 << 21)/* backed by heap memory */
#define _XBF_DELWRI_Q	(1 << 22)/* buffer on a delwri queue */

typedef unsigned int xfs_buf_flags_t;

#define XFS_BUF_FLAGS \
	{ XBF_READ,		"READ" }, \
	{ XBF_WRITE,		"WRITE" }, \
	{ XBF_READ_AHEAD,	"READ_AHEAD" }, \
	{ XBF_MAPPED,		"MAPPED" }, \
	{ XBF_ASYNC,		"ASYNC" }, \
	{ XBF_DONE,		"DONE" }, \
	{ XBF_STALE,		"STALE" }, \
	{ XBF_SYNCIO,		"SYNCIO" }, \
	{ XBF_FUA,		"FUA" }, \
	{ XBF_FLUSH,		"FLUSH" }, \
	{ XBF_TRYLOCK,		"TRYLOCK" }, 	/* should never be set */\
	{ _XBF_PAGES,		"PAGES" }, \
	{ _XBF_KMEM,		"KMEM" }, \
	{ _XBF_DELWRI_Q,	"DELWRI_Q" }

typedef struct xfs_buftarg {
	dev_t			bt_dev;
	struct block_device	*bt_bdev;
	struct backing_dev_info	*bt_bdi;
	struct xfs_mount	*bt_mount;
	unsigned int		bt_bsize;
	unsigned int		bt_sshift;
	size_t			bt_smask;

	/* LRU control structures */
	struct shrinker		bt_shrinker;
	struct list_head	bt_lru;
	spinlock_t		bt_lru_lock;
	unsigned int		bt_lru_nr;
} xfs_buftarg_t;

struct xfs_buf;
typedef void (*xfs_buf_iodone_t)(struct xfs_buf *);

#define XB_PAGES	2

typedef struct xfs_buf {
	/*
	 * first cacheline holds all the fields needed for an uncontended cache
	 * hit to be fully processed. The semaphore straddles the cacheline
	 * boundary, but the counter and lock sits on the first cacheline,
	 * which is the only bit that is touched if we hit the semaphore
	 * fast-path on locking.
	 */
	struct rb_node		b_rbnode;	/* rbtree node */
	xfs_daddr_t		b_bn;		/* block number for I/O */
	int			b_length;	/* size of buffer in BBs */
	atomic_t		b_hold;		/* reference count */
	atomic_t		b_lru_ref;	/* lru reclaim ref count */
	xfs_buf_flags_t		b_flags;	/* status flags */
	struct semaphore	b_sema;		/* semaphore for lockables */

	struct list_head	b_lru;		/* lru list */
	wait_queue_head_t	b_waiters;	/* unpin waiters */
	struct list_head	b_list;
	struct xfs_perag	*b_pag;		/* contains rbtree root */
	xfs_buftarg_t		*b_target;	/* buffer target (device) */
	void			*b_addr;	/* virtual address of buffer */
	struct work_struct	b_iodone_work;
	xfs_buf_iodone_t	b_iodone;	/* I/O completion function */
	struct completion	b_iowait;	/* queue for I/O waiters */
	void			*b_fspriv;
	struct xfs_trans	*b_transp;
	struct page		**b_pages;	/* array of page pointers */
	struct page		*b_page_array[XB_PAGES]; /* inline pages */
	int			b_io_length;	/* IO size in BBs */
	atomic_t		b_pin_count;	/* pin count */
	atomic_t		b_io_remaining;	/* #outstanding I/O requests */
	unsigned int		b_page_count;	/* size of page array */
	unsigned int		b_offset;	/* page offset in first page */
	unsigned short		b_error;	/* error code on I/O */
#ifdef XFS_BUF_LOCK_TRACKING
	int			b_last_holder;
#endif
} xfs_buf_t;


/* Finding and Reading Buffers */
struct xfs_buf *_xfs_buf_find(struct xfs_buftarg *target, xfs_daddr_t blkno,
				size_t numblks, xfs_buf_flags_t flags,
				struct xfs_buf *new_bp);
#define xfs_incore(buftarg,blkno,len,lockit) \
	_xfs_buf_find(buftarg, blkno ,len, lockit, NULL)

struct xfs_buf *xfs_buf_get(struct xfs_buftarg *target, xfs_daddr_t blkno,
				size_t numblks, xfs_buf_flags_t flags);
struct xfs_buf *xfs_buf_read(struct xfs_buftarg *target, xfs_daddr_t blkno,
				size_t numblks, xfs_buf_flags_t flags);
void xfs_buf_readahead(struct xfs_buftarg *target, xfs_daddr_t blkno,
				size_t numblks);

struct xfs_buf *xfs_buf_get_empty(struct xfs_buftarg *target, size_t numblks);
struct xfs_buf *xfs_buf_alloc(struct xfs_buftarg *target, xfs_daddr_t blkno,
				size_t numblks, xfs_buf_flags_t flags);
void xfs_buf_set_empty(struct xfs_buf *bp, size_t numblks);
int xfs_buf_associate_memory(struct xfs_buf *bp, void *mem, size_t length);

struct xfs_buf *xfs_buf_get_uncached(struct xfs_buftarg *target, size_t numblks,
				int flags);
struct xfs_buf *xfs_buf_read_uncached(struct xfs_buftarg *target,
				xfs_daddr_t daddr, size_t numblks, int flags);
void xfs_buf_hold(struct xfs_buf *bp);

/* Releasing Buffers */
extern void xfs_buf_free(xfs_buf_t *);
extern void xfs_buf_rele(xfs_buf_t *);

/* Locking and Unlocking Buffers */
extern int xfs_buf_trylock(xfs_buf_t *);
extern void xfs_buf_lock(xfs_buf_t *);
extern void xfs_buf_unlock(xfs_buf_t *);
#define xfs_buf_islocked(bp) \
	((bp)->b_sema.count <= 0)

/* Buffer Read and Write Routines */
extern int xfs_bwrite(struct xfs_buf *bp);

extern void xfsbdstrat(struct xfs_mount *, struct xfs_buf *);
extern int xfs_bdstrat_cb(struct xfs_buf *);

extern void xfs_buf_ioend(xfs_buf_t *,	int);
extern void xfs_buf_ioerror(xfs_buf_t *, int);
extern void xfs_buf_ioerror_alert(struct xfs_buf *, const char *func);
extern void xfs_buf_iorequest(xfs_buf_t *);
extern int xfs_buf_iowait(xfs_buf_t *);
extern void xfs_buf_iomove(xfs_buf_t *, size_t, size_t, void *,
				xfs_buf_rw_t);
#define xfs_buf_zero(bp, off, len) \
	    xfs_buf_iomove((bp), (off), (len), NULL, XBRW_ZERO)

static inline int xfs_buf_geterror(xfs_buf_t *bp)
{
	return bp ? bp->b_error : ENOMEM;
}

/* Buffer Utility Routines */
extern xfs_caddr_t xfs_buf_offset(xfs_buf_t *, size_t);

/* Delayed Write Buffer Routines */
extern bool xfs_buf_delwri_queue(struct xfs_buf *, struct list_head *);
extern int xfs_buf_delwri_submit(struct list_head *);
extern int xfs_buf_delwri_submit_nowait(struct list_head *);

/* Buffer Daemon Setup Routines */
extern int xfs_buf_init(void);
extern void xfs_buf_terminate(void);

#define XFS_BUF_ZEROFLAGS(bp) \
	((bp)->b_flags &= ~(XBF_READ|XBF_WRITE|XBF_ASYNC| \
			    XBF_SYNCIO|XBF_FUA|XBF_FLUSH))

void xfs_buf_stale(struct xfs_buf *bp);
#define XFS_BUF_UNSTALE(bp)	((bp)->b_flags &= ~XBF_STALE)
#define XFS_BUF_ISSTALE(bp)	((bp)->b_flags & XBF_STALE)

#define XFS_BUF_DONE(bp)	((bp)->b_flags |= XBF_DONE)
#define XFS_BUF_UNDONE(bp)	((bp)->b_flags &= ~XBF_DONE)
#define XFS_BUF_ISDONE(bp)	((bp)->b_flags & XBF_DONE)

#define XFS_BUF_ASYNC(bp)	((bp)->b_flags |= XBF_ASYNC)
#define XFS_BUF_UNASYNC(bp)	((bp)->b_flags &= ~XBF_ASYNC)
#define XFS_BUF_ISASYNC(bp)	((bp)->b_flags & XBF_ASYNC)

#define XFS_BUF_READ(bp)	((bp)->b_flags |= XBF_READ)
#define XFS_BUF_UNREAD(bp)	((bp)->b_flags &= ~XBF_READ)
#define XFS_BUF_ISREAD(bp)	((bp)->b_flags & XBF_READ)

#define XFS_BUF_WRITE(bp)	((bp)->b_flags |= XBF_WRITE)
#define XFS_BUF_UNWRITE(bp)	((bp)->b_flags &= ~XBF_WRITE)
#define XFS_BUF_ISWRITE(bp)	((bp)->b_flags & XBF_WRITE)

#define XFS_BUF_ADDR(bp)		((bp)->b_bn)
#define XFS_BUF_SET_ADDR(bp, bno)	((bp)->b_bn = (xfs_daddr_t)(bno))

static inline void xfs_buf_set_ref(struct xfs_buf *bp, int lru_ref)
{
	atomic_set(&bp->b_lru_ref, lru_ref);
}

static inline int xfs_buf_ispinned(struct xfs_buf *bp)
{
	return atomic_read(&bp->b_pin_count);
}

static inline void xfs_buf_relse(xfs_buf_t *bp)
{
	xfs_buf_unlock(bp);
	xfs_buf_rele(bp);
}

/*
 *	Handling of buftargs.
 */
extern xfs_buftarg_t *xfs_alloc_buftarg(struct xfs_mount *,
			struct block_device *, int, const char *);
extern void xfs_free_buftarg(struct xfs_mount *, struct xfs_buftarg *);
extern void xfs_wait_buftarg(xfs_buftarg_t *);
extern int xfs_setsize_buftarg(xfs_buftarg_t *, unsigned int, unsigned int);

#define xfs_getsize_buftarg(buftarg)	block_size((buftarg)->bt_bdev)
#define xfs_readonly_buftarg(buftarg)	bdev_read_only((buftarg)->bt_bdev)

#endif	/* __XFS_BUF_H__ */
Commit	Line	Data
1da177e4	1	/*
7b718769 NS	2	* Copyright (c) 2000-2005 Silicon Graphics, Inc.
7b718769 NS	3	* All Rights Reserved.
1da177e4	4	*
7b718769 NS	5	* This program is free software; you can redistribute it and/or
7b718769 NS	6	* modify it under the terms of the GNU General Public License as
1da177e4 LT	7	* published by the Free Software Foundation.
1da177e4 LT	8	*
7b718769 NS	9	* This program is distributed in the hope that it would be useful,
	10	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	11	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	12	* GNU General Public License for more details.
1da177e4	13	*
7b718769 NS	14	* You should have received a copy of the GNU General Public License
	15	* along with this program; if not, write the Free Software Foundation,
	16	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
1da177e4	17	*/
1da177e4 LT	18	#ifndef __XFS_BUF_H__
	19	#define __XFS_BUF_H__
	20
1da177e4 LT	21	#include <linux/list.h>
	22	#include <linux/types.h>
	23	#include <linux/spinlock.h>
1da177e4 LT	24	#include <linux/mm.h>
	25	#include <linux/fs.h>
	26	#include <linux/buffer_head.h>
	27	#include <linux/uio.h>
	28
	29	/*
	30	* Base types
	31	*/
	32
ce8e922c NS	33	#define XFS_BUF_DADDR_NULL ((xfs_daddr_t) (-1LL))
ce8e922c NS	34
ce8e922c NS	35	typedef enum {
	36	XBRW_READ = 1, /* transfer into target memory */
	37	XBRW_WRITE = 2, /* transfer from target memory */
	38	XBRW_ZERO = 3, /* Zero target memory */
	39	} xfs_buf_rw_t;
	40
807cbbdb CH	41	#define XBF_READ (1 << 0) /* buffer intended for reading from device */
807cbbdb CH	42	#define XBF_WRITE (1 << 1) /* buffer intended for writing to device */
1d5ae5df CH	43	#define XBF_READ_AHEAD (1 << 2) /* asynchronous read-ahead */
1d5ae5df CH	44	#define XBF_MAPPED (1 << 3) /* buffer mapped (b_addr valid) */
807cbbdb CH	45	#define XBF_ASYNC (1 << 4) /* initiator will not wait for completion */
807cbbdb CH	46	#define XBF_DONE (1 << 5) /* all pages in the buffer uptodate */
43ff2122	47	#define XBF_STALE (1 << 6) /* buffer has been staled, do not find it */
1d5ae5df CH	48
	49	/* I/O hints for the BIO layer */
	50	#define XBF_SYNCIO (1 << 10)/* treat this buffer as synchronous I/O */
	51	#define XBF_FUA (1 << 11)/* force cache write through mode */
	52	#define XBF_FLUSH (1 << 12)/* flush the disk cache before a write */
1da177e4	53
807cbbdb	54	/* flags used only as arguments to access routines */
1d5ae5df	55	#define XBF_TRYLOCK (1 << 16)/* lock requested, but do not wait */
1da177e4	56
807cbbdb	57	/* flags used only internally */
1d5ae5df CH	58	#define _XBF_PAGES (1 << 20)/* backed by refcounted pages */
1d5ae5df CH	59	#define _XBF_KMEM (1 << 21)/* backed by heap memory */
43ff2122	60	#define _XBF_DELWRI_Q (1 << 22)/* buffer on a delwri queue */
6ab455ee	61
807cbbdb	62	typedef unsigned int xfs_buf_flags_t;
1da177e4	63
0b1b213f CH	64	#define XFS_BUF_FLAGS \
	65	{ XBF_READ, "READ" }, \
	66	{ XBF_WRITE, "WRITE" }, \
1d5ae5df	67	{ XBF_READ_AHEAD, "READ_AHEAD" }, \
0b1b213f CH	68	{ XBF_MAPPED, "MAPPED" }, \
	69	{ XBF_ASYNC, "ASYNC" }, \
	70	{ XBF_DONE, "DONE" }, \
0b1b213f	71	{ XBF_STALE, "STALE" }, \
1d5ae5df CH	72	{ XBF_SYNCIO, "SYNCIO" }, \
	73	{ XBF_FUA, "FUA" }, \
	74	{ XBF_FLUSH, "FLUSH" }, \
a8acad70	75	{ XBF_TRYLOCK, "TRYLOCK" }, /* should never be set */\
0b1b213f	76	{ _XBF_PAGES, "PAGES" }, \
0e6e847f DC	77	{ _XBF_KMEM, "KMEM" }, \
0e6e847f DC	78	{ _XBF_DELWRI_Q, "DELWRI_Q" }
0b1b213f	79
1da177e4	80	typedef struct xfs_buftarg {
ce8e922c NS	81	dev_t bt_dev;
ce8e922c NS	82	struct block_device *bt_bdev;
0e6e847f	83	struct backing_dev_info *bt_bdi;
ebad861b	84	struct xfs_mount *bt_mount;
ce8e922c NS	85	unsigned int bt_bsize;
	86	unsigned int bt_sshift;
	87	size_t bt_smask;
	88
ff57ab21 DC	89	/* LRU control structures */
ff57ab21 DC	90	struct shrinker bt_shrinker;
430cbeb8 DC	91	struct list_head bt_lru;
	92	spinlock_t bt_lru_lock;
	93	unsigned int bt_lru_nr;
1da177e4 LT	94	} xfs_buftarg_t;
1da177e4 LT	95
1da177e4	96	struct xfs_buf;
ce8e922c	97	typedef void (xfs_buf_iodone_t)(struct xfs_buf );
1da177e4	98
ce8e922c	99	#define XB_PAGES 2
1da177e4 LT	100
1da177e4 LT	101	typedef struct xfs_buf {
50f59e8e DC	102	/*
	103	* first cacheline holds all the fields needed for an uncontended cache
	104	* hit to be fully processed. The semaphore straddles the cacheline
	105	* boundary, but the counter and lock sits on the first cacheline,
	106	* which is the only bit that is touched if we hit the semaphore
	107	* fast-path on locking.
	108	*/
	109	struct rb_node b_rbnode; /* rbtree node */
de1cbee4	110	xfs_daddr_t b_bn; /* block number for I/O */
4e94b71b	111	int b_length; /* size of buffer in BBs */
50f59e8e	112	atomic_t b_hold; /* reference count */
430cbeb8	113	atomic_t b_lru_ref; /* lru reclaim ref count */
50f59e8e	114	xfs_buf_flags_t b_flags; /* status flags */
ce8e922c	115	struct semaphore b_sema; /* semaphore for lockables */
50f59e8e	116
430cbeb8	117	struct list_head b_lru; /* lru list */
ce8e922c NS	118	wait_queue_head_t b_waiters; /* unpin waiters */
ce8e922c NS	119	struct list_head b_list;
74f75a0c	120	struct xfs_perag b_pag; / contains rbtree root */
ce8e922c	121	xfs_buftarg_t b_target; / buffer target (device) */
ce8e922c NS	122	void b_addr; / virtual address of buffer */
ce8e922c NS	123	struct work_struct b_iodone_work;
ce8e922c	124	xfs_buf_iodone_t b_iodone; /* I/O completion function */
b4dd330b	125	struct completion b_iowait; /* queue for I/O waiters */
ce8e922c	126	void *b_fspriv;
bf9d9013	127	struct xfs_trans *b_transp;
ce8e922c NS	128	struct page *b_pages; / array of page pointers */
ce8e922c NS	129	struct page b_page_array[XB_PAGES]; / inline pages */
aa0e8833	130	int b_io_length; /* IO size in BBs */
50f59e8e DC	131	atomic_t b_pin_count; /* pin count */
	132	atomic_t b_io_remaining; /* #outstanding I/O requests */
	133	unsigned int b_page_count; /* size of page array */
	134	unsigned int b_offset; /* page offset in first page */
	135	unsigned short b_error; /* error code on I/O */
ce8e922c NS	136	#ifdef XFS_BUF_LOCK_TRACKING
ce8e922c NS	137	int b_last_holder;
1da177e4 LT	138	#endif
	139	} xfs_buf_t;
	140
	141
	142	/* Finding and Reading Buffers */
e70b73f8 DC	143	struct xfs_buf _xfs_buf_find(struct xfs_buftarg target, xfs_daddr_t blkno,
	144	size_t numblks, xfs_buf_flags_t flags,
	145	struct xfs_buf *new_bp);
1da177e4	146	#define xfs_incore(buftarg,blkno,len,lockit) \
ce8e922c	147	_xfs_buf_find(buftarg, blkno ,len, lockit, NULL)
1da177e4	148
e70b73f8 DC	149	struct xfs_buf xfs_buf_get(struct xfs_buftarg target, xfs_daddr_t blkno,
	150	size_t numblks, xfs_buf_flags_t flags);
	151	struct xfs_buf xfs_buf_read(struct xfs_buftarg target, xfs_daddr_t blkno,
	152	size_t numblks, xfs_buf_flags_t flags);
	153	void xfs_buf_readahead(struct xfs_buftarg *target, xfs_daddr_t blkno,
	154	size_t numblks);
	155
	156	struct xfs_buf xfs_buf_get_empty(struct xfs_buftarg target, size_t numblks);
	157	struct xfs_buf xfs_buf_alloc(struct xfs_buftarg target, xfs_daddr_t blkno,
	158	size_t numblks, xfs_buf_flags_t flags);
	159	void xfs_buf_set_empty(struct xfs_buf *bp, size_t numblks);
	160	int xfs_buf_associate_memory(struct xfs_buf bp, void mem, size_t length);
	161
	162	struct xfs_buf xfs_buf_get_uncached(struct xfs_buftarg target, size_t numblks,
	163	int flags);
	164	struct xfs_buf xfs_buf_read_uncached(struct xfs_buftarg target,
	165	xfs_daddr_t daddr, size_t numblks, int flags);
	166	void xfs_buf_hold(struct xfs_buf *bp);
1da177e4 LT	167
1da177e4 LT	168	/* Releasing Buffers */
ce8e922c NS	169	extern void xfs_buf_free(xfs_buf_t *);
ce8e922c NS	170	extern void xfs_buf_rele(xfs_buf_t *);
1da177e4 LT	171
1da177e4 LT	172	/* Locking and Unlocking Buffers */
0c842ad4	173	extern int xfs_buf_trylock(xfs_buf_t *);
ce8e922c NS	174	extern void xfs_buf_lock(xfs_buf_t *);
ce8e922c NS	175	extern void xfs_buf_unlock(xfs_buf_t *);
0c842ad4 CH	176	#define xfs_buf_islocked(bp) \
0c842ad4 CH	177	((bp)->b_sema.count <= 0)
1da177e4 LT	178
1da177e4 LT	179	/* Buffer Read and Write Routines */
c2b006c1	180	extern int xfs_bwrite(struct xfs_buf *bp);
4e23471a CH	181
	182	extern void xfsbdstrat(struct xfs_mount , struct xfs_buf );
	183	extern int xfs_bdstrat_cb(struct xfs_buf *);
	184
ce8e922c NS	185	extern void xfs_buf_ioend(xfs_buf_t *, int);
ce8e922c NS	186	extern void xfs_buf_ioerror(xfs_buf_t *, int);
901796af	187	extern void xfs_buf_ioerror_alert(struct xfs_buf , const char func);
0e95f19a	188	extern void xfs_buf_iorequest(xfs_buf_t *);
ce8e922c	189	extern int xfs_buf_iowait(xfs_buf_t *);
b9c48649	190	extern void xfs_buf_iomove(xfs_buf_t , size_t, size_t, void ,
ce8e922c	191	xfs_buf_rw_t);
1a1a3e97 CH	192	#define xfs_buf_zero(bp, off, len) \
1a1a3e97 CH	193	xfs_buf_iomove((bp), (off), (len), NULL, XBRW_ZERO)
ce8e922c	194
ce8e922c	195	static inline int xfs_buf_geterror(xfs_buf_t *bp)
1da177e4	196	{
ce8e922c	197	return bp ? bp->b_error : ENOMEM;
1da177e4 LT	198	}
	199
	200	/* Buffer Utility Routines */
ce8e922c	201	extern xfs_caddr_t xfs_buf_offset(xfs_buf_t *, size_t);
1da177e4	202
1da177e4	203	/* Delayed Write Buffer Routines */
43ff2122 CH	204	extern bool xfs_buf_delwri_queue(struct xfs_buf , struct list_head );
	205	extern int xfs_buf_delwri_submit(struct list_head *);
	206	extern int xfs_buf_delwri_submit_nowait(struct list_head *);
1da177e4 LT	207
1da177e4 LT	208	/* Buffer Daemon Setup Routines */
ce8e922c NS	209	extern int xfs_buf_init(void);
ce8e922c NS	210	extern void xfs_buf_terminate(void);
1da177e4	211
1d5ae5df	212	#define XFS_BUF_ZEROFLAGS(bp) \
43ff2122	213	((bp)->b_flags &= ~(XBF_READ\|XBF_WRITE\|XBF_ASYNC\| \
1d5ae5df	214	XBF_SYNCIO\|XBF_FUA\|XBF_FLUSH))
ce8e922c	215
430cbeb8	216	void xfs_buf_stale(struct xfs_buf *bp);
0cadda1c CH	217	#define XFS_BUF_UNSTALE(bp) ((bp)->b_flags &= ~XBF_STALE)
0cadda1c CH	218	#define XFS_BUF_ISSTALE(bp) ((bp)->b_flags & XBF_STALE)
1da177e4	219
ce8e922c NS	220	#define XFS_BUF_DONE(bp) ((bp)->b_flags \|= XBF_DONE)
	221	#define XFS_BUF_UNDONE(bp) ((bp)->b_flags &= ~XBF_DONE)
	222	#define XFS_BUF_ISDONE(bp) ((bp)->b_flags & XBF_DONE)
	223
ce8e922c NS	224	#define XFS_BUF_ASYNC(bp) ((bp)->b_flags \|= XBF_ASYNC)
	225	#define XFS_BUF_UNASYNC(bp) ((bp)->b_flags &= ~XBF_ASYNC)
	226	#define XFS_BUF_ISASYNC(bp) ((bp)->b_flags & XBF_ASYNC)
	227
ce8e922c NS	228	#define XFS_BUF_READ(bp) ((bp)->b_flags \|= XBF_READ)
	229	#define XFS_BUF_UNREAD(bp) ((bp)->b_flags &= ~XBF_READ)
	230	#define XFS_BUF_ISREAD(bp) ((bp)->b_flags & XBF_READ)
	231
	232	#define XFS_BUF_WRITE(bp) ((bp)->b_flags \|= XBF_WRITE)
	233	#define XFS_BUF_UNWRITE(bp) ((bp)->b_flags &= ~XBF_WRITE)
	234	#define XFS_BUF_ISWRITE(bp) ((bp)->b_flags & XBF_WRITE)
	235
ce8e922c NS	236	#define XFS_BUF_ADDR(bp) ((bp)->b_bn)
ce8e922c NS	237	#define XFS_BUF_SET_ADDR(bp, bno) ((bp)->b_bn = (xfs_daddr_t)(bno))
ce8e922c	238
38f23232	239	static inline void xfs_buf_set_ref(struct xfs_buf *bp, int lru_ref)
821eb21d DC	240	{
	241	atomic_set(&bp->b_lru_ref, lru_ref);
	242	}
ce8e922c	243
811e64c7 CS	244	static inline int xfs_buf_ispinned(struct xfs_buf *bp)
	245	{
	246	return atomic_read(&bp->b_pin_count);
	247	}
ce8e922c	248
ce8e922c	249	static inline void xfs_buf_relse(xfs_buf_t *bp)
1da177e4	250	{
bfc60177	251	xfs_buf_unlock(bp);
ce8e922c	252	xfs_buf_rele(bp);
1da177e4 LT	253	}
1da177e4 LT	254
1da177e4 LT	255	/*
	256	* Handling of buftargs.
	257	*/
ebad861b DC	258	extern xfs_buftarg_t xfs_alloc_buftarg(struct xfs_mount ,
ebad861b DC	259	struct block_device , int, const char );
c141b292	260	extern void xfs_free_buftarg(struct xfs_mount , struct xfs_buftarg );
1da177e4 LT	261	extern void xfs_wait_buftarg(xfs_buftarg_t *);
1da177e4 LT	262	extern int xfs_setsize_buftarg(xfs_buftarg_t *, unsigned int, unsigned int);
d808f617	263
ce8e922c NS	264	#define xfs_getsize_buftarg(buftarg) block_size((buftarg)->bt_bdev)
	265	#define xfs_readonly_buftarg(buftarg) bdev_read_only((buftarg)->bt_bdev)
	266
1da177e4	267	#endif /* __XFS_BUF_H__ */