/*
* Copyright (c) 1982, 1986, 1989, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)buf.h 8.7 (Berkeley) 1/21/94
* $Id: buf.h,v 1.26 1995/12/28 23:34:28 davidg Exp $
*/
#ifndef _SYS_BUF_H_
#define _SYS_BUF_H_
#include <sys/queue.h>
#define NOLIST ((struct buf *)0x87654321)
struct buf;
struct iodone_chain {
long ic_prev_flags;
void (*ic_prev_iodone) __P((struct buf *));
void *ic_prev_iodone_chain;
struct {
long ia_long;
void *ia_ptr;
} ic_args[5];
};
typedef TAILQ_HEAD(buf_queue_head, buf) buf_queue_head, *buf_queue_head_t;
/*
* The buffer header describes an I/O operation in the kernel.
*/
struct buf {
LIST_ENTRY(buf) b_hash; /* Hash chain. */
LIST_ENTRY(buf) b_vnbufs; /* Buffer's associated vnode. */
TAILQ_ENTRY(buf) b_freelist; /* Free list position if not active. */
struct buf *b_actf, **b_actb; /* Device driver queue when active. *depricated* XXX */
TAILQ_ENTRY(buf) b_act; /* Device driver queue when active. *new* */
struct proc *b_proc; /* Associated proc; NULL if kernel. */
long b_flags; /* B_* flags. */
unsigned short b_qindex; /* buffer queue index */
unsigned char b_usecount; /* buffer use count */
int b_error; /* Errno value. */
long b_bufsize; /* Allocated buffer size. */
long b_bcount; /* Valid bytes in buffer. */
long b_resid; /* Remaining I/O. */
dev_t b_dev; /* Device associated with buffer. */
struct {
caddr_t b_addr; /* Memory, superblocks, indirect etc. */
} b_un;
void *b_saveaddr; /* Original b_addr for physio. */
daddr_t b_lblkno; /* Logical block number. */
daddr_t b_blkno; /* Underlying physical block number. */
/* Function to call upon completion. */
void (*b_iodone) __P((struct buf *));
/* For nested b_iodone's. */
struct iodone_chain *b_iodone_chain;
struct vnode *b_vp; /* Device vnode. */
int b_dirtyoff; /* Offset in buffer of dirty region. */
int b_dirtyend; /* Offset of end of dirty region. */
struct ucred *b_rcred; /* Read credentials reference. */
struct ucred *b_wcred; /* Write credentials reference. */
int b_validoff; /* Offset in buffer of valid region. */
int b_validend; /* Offset of end of valid region. */
daddr_t b_pblkno; /* physical block number */
caddr_t b_savekva; /* saved kva for transfer while bouncing */
void *b_driver1; /* for private use by the driver */
void *b_driver2; /* for private use by the driver */
void *b_spc;
union cluster_info {
TAILQ_HEAD(cluster_list_head, buf) cluster_head;
TAILQ_ENTRY(buf) cluster_entry;
} b_cluster;
struct vm_page *b_pages[(MAXPHYS + PAGE_SIZE - 1)/PAGE_SIZE];
int b_npages;
};
/* Device driver compatibility definitions. */
#define b_active b_bcount /* Driver queue head: drive active. */
#define b_data b_un.b_addr /* b_un.b_addr is not changeable. */
#define b_errcnt b_resid /* Retry count while I/O in progress. */
#define iodone biodone /* Old name for biodone. */
#define iowait biowait /* Old name for biowait. */
/*
* These flags are kept in b_flags.
*/
#define B_AGE 0x00000001 /* Move to age queue when I/O done. */
#define B_APPENDWRITE 0x00000002 /* Append-write in progress. */
#define B_ASYNC 0x00000004 /* Start I/O, do not wait. */
#define B_BAD 0x00000008 /* Bad block revectoring in progress. */
#define B_BUSY 0x00000010 /* I/O in progress. */
#define B_CACHE 0x00000020 /* Bread found us in the cache. */
#define B_CALL 0x00000040 /* Call b_iodone from biodone. */
#define B_DELWRI 0x00000080 /* Delay I/O until buffer reused. */
#define B_DIRTY 0x00000100 /* Dirty page to be pushed out async. */
#define B_DONE 0x00000200 /* I/O completed. */
#define B_EINTR 0x00000400 /* I/O was interrupted */
#define B_ERROR 0x00000800 /* I/O error occurred. */
#define B_GATHERED 0x00001000 /* LFS: already in a segment. */
#define B_INVAL 0x00002000 /* Does not contain valid info. */
#define B_LOCKED 0x00004000 /* Locked in core (not reusable). */
#define B_NOCACHE 0x00008000 /* Do not cache block after use. */
#define B_MALLOC 0x00010000 /* malloced b_data */
#define B_CLUSTEROK 0x00020000 /* Pagein op, so swap() can count it. */
#define B_PHYS 0x00040000 /* I/O to user memory. */
#define B_RAW 0x00080000 /* Set by physio for raw transfers. */
#define B_READ 0x00100000 /* Read buffer. */
#define B_TAPE 0x00200000 /* Magnetic tape I/O. */
#define B_RELBUF 0x00400000 /* Release VMIO buffer. */
#define B_WANTED 0x00800000 /* Process wants this buffer. */
#define B_WRITE 0x00000000 /* Write buffer (pseudo flag). */
#define B_WRITEINPROG 0x01000000 /* Write in progress. */
#define B_XXX 0x02000000 /* Debugging flag. */
#define B_PAGING 0x04000000 /* volatile paging I/O -- bypass VMIO */
#define B_VMIO 0x20000000 /* VMIO flag */
#define B_CLUSTER 0x40000000 /* pagein op, so swap() can count it */
#define B_BOUNCE 0x80000000 /* bounce buffer flag */
/*
* number of buffer hash entries
*/
#define BUFHSZ 512
/*
* buffer hash table calculation, originally by David Greenman
*/
#define BUFHASH(vnp, bn) \
(&bufhashtbl[(((unsigned long)(vnp) >> 7)+(int)(bn)) % BUFHSZ])
/*
* Definitions for the buffer free lists.
*/
#define BUFFER_QUEUES 6 /* number of free buffer queues */
extern LIST_HEAD(bufhashhdr, buf) bufhashtbl[BUFHSZ], invalhash;
extern TAILQ_HEAD(bqueues, buf) bufqueues[BUFFER_QUEUES];
#define QUEUE_NONE 0 /* on no queue */
#define QUEUE_LOCKED 1 /* locked buffers */
#define QUEUE_LRU 2 /* useful buffers */
#define QUEUE_VMIO 3 /* VMIO buffers */
#define QUEUE_AGE 4 /* not-useful buffers */
#define QUEUE_EMPTY 5 /* empty buffer headers*/
/*
* Zero out the buffer's data area.
*/
#define clrbuf(bp) { \
bzero((bp)->b_data, (u_int)(bp)->b_bcount); \
(bp)->b_resid = 0; \
}
/* Flags to low-level allocation routines. */
#define B_CLRBUF 0x01 /* Request allocated buffer be cleared. */
#define B_SYNC 0x02 /* Do all allocations synchronously. */
#ifdef KERNEL
extern int nbuf; /* The number of buffer headers */
extern struct buf *buf; /* The buffer headers. */
extern char *buffers; /* The buffer contents. */
extern int bufpages; /* Number of memory pages in the buffer pool. */
extern struct buf *swbuf; /* Swap I/O buffer headers. */
extern int nswbuf; /* Number of swap I/O buffer headers. */
extern TAILQ_HEAD(swqueue, buf) bswlist;
__BEGIN_DECLS
void bufinit __P((void));
void bremfree __P((struct buf *));
int bread __P((struct vnode *, daddr_t, int,
struct ucred *, struct buf **));
int breadn __P((struct vnode *, daddr_t, int, daddr_t *, int *, int,
struct ucred *, struct buf **));
int bwrite __P((struct buf *));
void bdwrite __P((struct buf *));
void bawrite __P((struct buf *));
void brelse __P((struct buf *));
void bqrelse __P((struct buf *));
int vfs_bio_awrite __P((struct buf *));
struct buf * getpbuf __P((void));
struct buf *incore __P((struct vnode *, daddr_t));
struct buf *gbincore __P((struct vnode *, daddr_t));
int inmem __P((struct vnode *, daddr_t));
struct buf *getblk __P((struct vnode *, daddr_t, int, int, int));
struct buf *geteblk __P((int));
int allocbuf __P((struct buf *, int));
int biowait __P((struct buf *));
void biodone __P((struct buf *));
void cluster_callback __P((struct buf *));
int cluster_read __P((struct vnode *, u_quad_t, daddr_t, long,
struct ucred *, struct buf **));
int cluster_wbuild __P((struct vnode *, long, daddr_t, int));
void cluster_write __P((struct buf *, u_quad_t));
int physio __P((void (*)(struct buf *), struct buf *, dev_t,
int, u_int (*)(struct buf *), struct uio *));
u_int minphys __P((struct buf *));
void vfs_bio_clrbuf __P((struct buf *));
void vfs_busy_pages __P((struct buf *, int clear_modify));
void vfs_unbusy_pages(struct buf *);
void vwakeup __P((struct buf *));
void vmapbuf __P((struct buf *));
void vunmapbuf __P((struct buf *));
void relpbuf __P((struct buf *));
void brelvp __P((struct buf *));
void bgetvp __P((struct vnode *, struct buf *));
void pbgetvp __P((struct vnode *, struct buf *));
void pbrelvp __P((struct buf *));
void reassignbuf __P((struct buf *, struct vnode *));
struct buf *trypbuf __P((void));
void vm_bounce_alloc __P((struct buf *));
void vm_bounce_free __P((struct buf *));
vm_offset_t vm_bounce_kva_alloc __P((int));
void vm_bounce_kva_alloc_free __P((vm_offset_t, int));
__END_DECLS
#endif
#endif /* !_SYS_BUF_H_ */
