619 lines
21 KiB
C
619 lines
21 KiB
C
/*
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* Copyright (c) 1982, 1986, 1989, 1993
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* The Regents of the University of California. All rights reserved.
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* (c) UNIX System Laboratories, Inc.
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* All or some portions of this file are derived from material licensed
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* to the University of California by American Telephone and Telegraph
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* Co. or Unix System Laboratories, Inc. and are reproduced herein with
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* the permission of UNIX System Laboratories, Inc.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by the University of
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* California, Berkeley and its contributors.
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* 4. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* @(#)buf.h 8.9 (Berkeley) 3/30/95
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* $FreeBSD$
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*/
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#ifndef _SYS_BUF_H_
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#define _SYS_BUF_H_
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#include <sys/queue.h>
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#include <sys/lock.h>
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struct bio;
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struct buf;
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struct mount;
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struct vnode;
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/*
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* To avoid including <ufs/ffs/softdep.h>
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*/
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LIST_HEAD(workhead, worklist);
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/*
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* These are currently used only by the soft dependency code, hence
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* are stored once in a global variable. If other subsystems wanted
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* to use these hooks, a pointer to a set of bio_ops could be added
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* to each buffer.
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*/
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extern struct bio_ops {
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void (*io_start) __P((struct buf *));
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void (*io_complete) __P((struct buf *));
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void (*io_deallocate) __P((struct buf *));
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int (*io_fsync) __P((struct vnode *));
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int (*io_sync) __P((struct mount *));
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void (*io_movedeps) __P((struct buf *, struct buf *));
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int (*io_countdeps) __P((struct buf *, int));
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} bioops;
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struct iodone_chain {
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long ic_prev_flags;
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void (*ic_prev_iodone) __P((struct bio *));
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void *ic_prev_iodone_chain;
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struct {
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long ia_long;
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void *ia_ptr;
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} ic_args[5];
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};
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/*
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* The bio structure describes an I/O operation in the kernel.
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*/
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struct bio {
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u_int bio_cmd; /* I/O operation. */
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dev_t bio_dev; /* Device to do I/O on. */
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daddr_t bio_blkno; /* Underlying physical block number. */
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off_t bio_offset; /* Offset into file. */
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long bio_bcount; /* Valid bytes in buffer. */
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caddr_t bio_data; /* Memory, superblocks, indirect etc. */
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u_int bio_flags; /* BIO_ flags. */
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struct buf *_bio_buf; /* Parent buffer. */
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int bio_error; /* Errno for BIO_ERROR. */
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long bio_resid; /* Remaining I/0 in bytes. */
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void (*bio_done) __P((struct bio *));
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void *bio_driver1; /* Private use by the callee. */
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void *bio_driver2; /* Private use by the callee. */
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void *bio_caller1; /* Private use by the caller. */
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void *bio_caller2; /* Private use by the caller. */
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TAILQ_ENTRY(bio) bio_queue; /* Disksort queue. */
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/* XXX: these go away when bio chaining is introduced */
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daddr_t bio_pblkno; /* physical block number */
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struct iodone_chain *bio_done_chain;
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};
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static __inline__ void
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biodone(struct bio *bp)
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{
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bp->bio_done(bp);
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}
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/*
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* The buffer header describes an I/O operation in the kernel.
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*
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* NOTES:
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* b_bufsize, b_bcount. b_bufsize is the allocation size of the
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* buffer, either DEV_BSIZE or PAGE_SIZE aligned. b_bcount is the
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* originally requested buffer size and can serve as a bounds check
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* against EOF. For most, but not all uses, b_bcount == b_bufsize.
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*
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* b_dirtyoff, b_dirtyend. Buffers support piecemeal, unaligned
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* ranges of dirty data that need to be written to backing store.
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* The range is typically clipped at b_bcount ( not b_bufsize ).
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*
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* b_resid. Number of bytes remaining in I/O. After an I/O operation
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* completes, b_resid is usually 0 indicating 100% success.
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*/
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struct buf {
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/* XXX: b_io must be the first element of struct buf for now /phk */
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struct bio b_io; /* "Builtin" I/O request. */
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#define b_bcount b_io.bio_bcount
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#define b_blkno b_io.bio_blkno
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#define b_caller1 b_io.bio_caller1
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#define b_data b_io.bio_data
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#define b_dev b_io.bio_dev
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#define b_driver1 b_io.bio_driver1
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#define b_driver2 b_io.bio_driver2
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#define b_error b_io.bio_error
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#define b_iocmd b_io.bio_cmd
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#define b_ioflags b_io.bio_flags
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#define b_pblkno b_io.bio_pblkno
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#define b_resid b_io.bio_resid
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void (*b_iodone) __P((struct buf *));
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off_t b_offset; /* Offset into file. */
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LIST_ENTRY(buf) b_hash; /* Hash chain. */
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TAILQ_ENTRY(buf) b_vnbufs; /* Buffer's associated vnode. */
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TAILQ_ENTRY(buf) b_freelist; /* Free list position if not active. */
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TAILQ_ENTRY(buf) b_act; /* Device driver queue when active. *new* */
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long b_flags; /* B_* flags. */
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unsigned short b_qindex; /* buffer queue index */
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unsigned char b_xflags; /* extra flags */
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struct lock b_lock; /* Buffer lock */
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long b_bufsize; /* Allocated buffer size. */
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caddr_t b_kvabase; /* base kva for buffer */
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int b_kvasize; /* size of kva for buffer */
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daddr_t b_lblkno; /* Logical block number. */
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struct vnode *b_vp; /* Device vnode. */
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int b_dirtyoff; /* Offset in buffer of dirty region. */
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int b_dirtyend; /* Offset of end of dirty region. */
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struct ucred *b_rcred; /* Read credentials reference. */
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struct ucred *b_wcred; /* Write credentials reference. */
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void *b_saveaddr; /* Original b_addr for physio. */
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union pager_info {
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void *pg_spc;
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int pg_reqpage;
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} b_pager;
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union cluster_info {
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TAILQ_HEAD(cluster_list_head, buf) cluster_head;
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TAILQ_ENTRY(buf) cluster_entry;
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} b_cluster;
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struct vm_page *b_pages[btoc(MAXPHYS)];
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int b_npages;
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struct workhead b_dep; /* List of filesystem dependencies. */
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struct chain_info { /* buffer chaining */
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struct buf *parent;
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int count;
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} b_chain;
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};
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#define b_spc b_pager.pg_spc
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/*
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* These flags are kept in b_flags.
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*
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* Notes:
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*
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* B_ASYNC VOP calls on bp's are usually async whether or not
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* B_ASYNC is set, but some subsystems, such as NFS, like
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* to know what is best for the caller so they can
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* optimize the I/O.
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*
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* B_PAGING Indicates that bp is being used by the paging system or
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* some paging system and that the bp is not linked into
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* the b_vp's clean/dirty linked lists or ref counts.
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* Buffer vp reassignments are illegal in this case.
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*
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* B_CACHE This may only be set if the buffer is entirely valid.
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* The situation where B_DELWRI is set and B_CACHE is
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* clear MUST be committed to disk by getblk() so
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* B_DELWRI can also be cleared. See the comments for
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* getblk() in kern/vfs_bio.c. If B_CACHE is clear,
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* the caller is expected to clear BIO_ERROR and B_INVAL,
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* set BIO_READ, and initiate an I/O.
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*
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* The 'entire buffer' is defined to be the range from
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* 0 through b_bcount.
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*
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* B_MALLOC Request that the buffer be allocated from the malloc
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* pool, DEV_BSIZE aligned instead of PAGE_SIZE aligned.
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*
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* B_CLUSTEROK This flag is typically set for B_DELWRI buffers
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* by filesystems that allow clustering when the buffer
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* is fully dirty and indicates that it may be clustered
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* with other adjacent dirty buffers. Note the clustering
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* may not be used with the stage 1 data write under NFS
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* but may be used for the commit rpc portion.
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*
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* B_VMIO Indicates that the buffer is tied into an VM object.
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* The buffer's data is always PAGE_SIZE aligned even
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* if b_bufsize and b_bcount are not. ( b_bufsize is
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* always at least DEV_BSIZE aligned, though ).
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*
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*/
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#define BIO_READ 1
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#define BIO_WRITE 2
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#define BIO_DELETE 4
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#define BIO_FORMAT 8
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#define BIO_ERROR 0x00000001
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#define BIO_ORDERED 0x00000002
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#define B_AGE 0x00000001 /* Move to age queue when I/O done. */
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#define B_NEEDCOMMIT 0x00000002 /* Append-write in progress. */
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#define B_ASYNC 0x00000004 /* Start I/O, do not wait. */
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#define B_UNUSED0 0x00000008 /* Old B_BAD */
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#define B_DEFERRED 0x00000010 /* Skipped over for cleaning */
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#define B_CACHE 0x00000020 /* Bread found us in the cache. */
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#define B_UNUSED40 0x00000040 /* Old B_CALL */
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#define B_DELWRI 0x00000080 /* Delay I/O until buffer reused. */
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#define B_DONE 0x00000200 /* I/O completed. */
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#define B_EINTR 0x00000400 /* I/O was interrupted */
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#define B_ERROR 0x00000800 /* I/O error occurred. */
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#define B_SCANNED 0x00001000 /* VOP_FSYNC funcs mark written bufs */
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#define B_INVAL 0x00002000 /* Does not contain valid info. */
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#define B_LOCKED 0x00004000 /* Locked in core (not reusable). */
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#define B_NOCACHE 0x00008000 /* Do not cache block after use. */
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#define B_MALLOC 0x00010000 /* malloced b_data */
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#define B_CLUSTEROK 0x00020000 /* Pagein op, so swap() can count it. */
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#define B_PHYS 0x00040000 /* I/O to user memory. */
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#define B_RAW 0x00080000 /* Set by physio for raw transfers. */
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#define B_DIRTY 0x00200000 /* Needs writing later. */
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#define B_RELBUF 0x00400000 /* Release VMIO buffer. */
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#define B_WANT 0x00800000 /* Used by vm_pager.c */
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#define B_WRITEINPROG 0x01000000 /* Write in progress. */
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#define B_XXX 0x02000000 /* Debugging flag. */
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#define B_PAGING 0x04000000 /* volatile paging I/O -- bypass VMIO */
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#define B_ORDERED 0x08000000 /* Must guarantee I/O ordering */
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#define B_RAM 0x10000000 /* Read ahead mark (flag) */
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#define B_VMIO 0x20000000 /* VMIO flag */
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#define B_CLUSTER 0x40000000 /* pagein op, so swap() can count it */
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#define B_AUTOCHAINDONE 0x80000000 /* Available flag */
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#define PRINT_BUF_FLAGS "\20\40autochain\37cluster\36vmio\35ram\34ordered" \
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"\33paging\32xxx\31writeinprog\30want\27relbuf\26dirty" \
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"\25read\24raw\23phys\22clusterok\21malloc\20nocache" \
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"\17locked\16inval\15scanned\14error\13eintr\12done\11freebuf" \
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"\10delwri\7call\6cache\4bad\3async\2needcommit\1age"
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/*
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* These flags are kept in b_xflags.
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*/
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#define BX_VNDIRTY 0x00000001 /* On vnode dirty list */
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#define BX_VNCLEAN 0x00000002 /* On vnode clean list */
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#define BX_BKGRDWRITE 0x00000004 /* Do writes in background */
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#define BX_BKGRDINPROG 0x00000008 /* Background write in progress */
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#define BX_BKGRDWAIT 0x00000010 /* Background write waiting */
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#define NOOFFSET (-1LL) /* No buffer offset calculated yet */
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#ifdef _KERNEL
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/*
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* Buffer locking
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*/
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extern struct simplelock buftimelock; /* Interlock on setting prio and timo */
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extern char *buf_wmesg; /* Default buffer lock message */
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#define BUF_WMESG "bufwait"
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#include <sys/proc.h> /* XXX for curproc */
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/*
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* Initialize a lock.
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*/
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#define BUF_LOCKINIT(bp) \
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lockinit(&(bp)->b_lock, PRIBIO + 4, buf_wmesg, 0, 0)
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/*
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*
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* Get a lock sleeping non-interruptably until it becomes available.
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*/
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static __inline int BUF_LOCK __P((struct buf *, int));
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static __inline int
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BUF_LOCK(struct buf *bp, int locktype)
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{
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int s, ret;
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s = splbio();
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simple_lock(&buftimelock);
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locktype |= LK_INTERLOCK;
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bp->b_lock.lk_wmesg = buf_wmesg;
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bp->b_lock.lk_prio = PRIBIO + 4;
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bp->b_lock.lk_timo = 0;
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ret = lockmgr(&(bp)->b_lock, locktype, &buftimelock, curproc);
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splx(s);
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return ret;
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}
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/*
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* Get a lock sleeping with specified interruptably and timeout.
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*/
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static __inline int BUF_TIMELOCK __P((struct buf *, int, char *, int, int));
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static __inline int
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BUF_TIMELOCK(struct buf *bp, int locktype, char *wmesg, int catch, int timo)
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{
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int s, ret;
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s = splbio();
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simple_lock(&buftimelock);
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locktype |= LK_INTERLOCK;
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bp->b_lock.lk_wmesg = wmesg;
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bp->b_lock.lk_prio = (PRIBIO + 4) | catch;
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bp->b_lock.lk_timo = timo;
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ret = lockmgr(&(bp)->b_lock, (locktype), &buftimelock, curproc);
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splx(s);
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return ret;
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}
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/*
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* Release a lock. Only the acquiring process may free the lock unless
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* it has been handed off to biodone.
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*/
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static __inline void BUF_UNLOCK __P((struct buf *));
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static __inline void
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BUF_UNLOCK(struct buf *bp)
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{
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int s;
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s = splbio();
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lockmgr(&(bp)->b_lock, LK_RELEASE, NULL, curproc);
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splx(s);
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}
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/*
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* Free a buffer lock.
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*/
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#define BUF_LOCKFREE(bp) \
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if (BUF_REFCNT(bp) > 0) \
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panic("free locked buf")
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/*
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* When initiating asynchronous I/O, change ownership of the lock to the
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* kernel. Once done, the lock may legally released by biodone. The
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* original owning process can no longer acquire it recursively, but must
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* wait until the I/O is completed and the lock has been freed by biodone.
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*/
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static __inline void BUF_KERNPROC __P((struct buf *));
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static __inline void
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BUF_KERNPROC(struct buf *bp)
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{
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struct proc *p = curproc;
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if (p != NULL && bp->b_lock.lk_lockholder == p->p_pid)
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p->p_locks--;
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bp->b_lock.lk_lockholder = LK_KERNPROC;
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}
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/*
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* Find out the number of references to a lock.
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*/
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static __inline int BUF_REFCNT __P((struct buf *));
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static __inline int
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BUF_REFCNT(struct buf *bp)
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{
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int s, ret;
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s = splbio();
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ret = lockcount(&(bp)->b_lock);
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splx(s);
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return ret;
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}
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#endif /* _KERNEL */
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struct buf_queue_head {
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TAILQ_HEAD(buf_queue, buf) queue;
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daddr_t last_pblkno;
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struct buf *insert_point;
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struct buf *switch_point;
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};
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struct bio_queue_head {
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TAILQ_HEAD(bio_queue, bio) queue;
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daddr_t last_pblkno;
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struct bio *insert_point;
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struct bio *switch_point;
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};
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/*
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* This structure describes a clustered I/O. It is stored in the b_saveaddr
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* field of the buffer on which I/O is done. At I/O completion, cluster
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* callback uses the structure to parcel I/O's to individual buffers, and
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* then free's this structure.
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*/
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struct cluster_save {
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long bs_bcount; /* Saved b_bcount. */
|
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long bs_bufsize; /* Saved b_bufsize. */
|
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void *bs_saveaddr; /* Saved b_addr. */
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int bs_nchildren; /* Number of associated buffers. */
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struct buf **bs_children; /* List of associated buffers. */
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};
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#ifdef _KERNEL
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static __inline void bufq_init __P((struct buf_queue_head *head));
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static __inline void bioq_init __P((struct bio_queue_head *head));
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static __inline void bufq_insert_tail __P((struct buf_queue_head *head,
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struct buf *bp));
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static __inline void bioq_insert_tail __P((struct bio_queue_head *head,
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struct bio *bp));
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static __inline void bufq_remove __P((struct buf_queue_head *head,
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struct buf *bp));
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static __inline void bioq_remove __P((struct bio_queue_head *head,
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struct bio *bp));
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static __inline struct buf *bufq_first __P((struct buf_queue_head *head));
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static __inline struct bio *bioq_first __P((struct bio_queue_head *head));
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static __inline void
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bufq_init(struct buf_queue_head *head)
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{
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TAILQ_INIT(&head->queue);
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head->last_pblkno = 0;
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head->insert_point = NULL;
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head->switch_point = NULL;
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}
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static __inline void
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bioq_init(struct bio_queue_head *head)
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{
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TAILQ_INIT(&head->queue);
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head->last_pblkno = 0;
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head->insert_point = NULL;
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head->switch_point = NULL;
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}
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static __inline void
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bufq_insert_tail(struct buf_queue_head *head, struct buf *bp)
|
|
{
|
|
if ((bp->b_ioflags & BIO_ORDERED) != 0) {
|
|
head->insert_point = bp;
|
|
head->switch_point = NULL;
|
|
}
|
|
TAILQ_INSERT_TAIL(&head->queue, bp, b_act);
|
|
}
|
|
|
|
static __inline void
|
|
bioq_insert_tail(struct bio_queue_head *head, struct bio *bp)
|
|
{
|
|
if ((bp->bio_flags & BIO_ORDERED) != 0) {
|
|
head->insert_point = bp;
|
|
head->switch_point = NULL;
|
|
}
|
|
TAILQ_INSERT_TAIL(&head->queue, bp, bio_queue);
|
|
}
|
|
|
|
static __inline void
|
|
bufq_remove(struct buf_queue_head *head, struct buf *bp)
|
|
{
|
|
if (bp == head->switch_point)
|
|
head->switch_point = TAILQ_NEXT(bp, b_act);
|
|
if (bp == head->insert_point) {
|
|
head->insert_point = TAILQ_PREV(bp, buf_queue, b_act);
|
|
if (head->insert_point == NULL)
|
|
head->last_pblkno = 0;
|
|
} else if (bp == TAILQ_FIRST(&head->queue))
|
|
head->last_pblkno = bp->b_pblkno;
|
|
TAILQ_REMOVE(&head->queue, bp, b_act);
|
|
if (TAILQ_FIRST(&head->queue) == head->switch_point)
|
|
head->switch_point = NULL;
|
|
}
|
|
|
|
static __inline void
|
|
bioq_remove(struct bio_queue_head *head, struct bio *bp)
|
|
{
|
|
if (bp == head->switch_point)
|
|
head->switch_point = TAILQ_NEXT(bp, bio_queue);
|
|
if (bp == head->insert_point) {
|
|
head->insert_point = TAILQ_PREV(bp, bio_queue, bio_queue);
|
|
if (head->insert_point == NULL)
|
|
head->last_pblkno = 0;
|
|
} else if (bp == TAILQ_FIRST(&head->queue))
|
|
head->last_pblkno = bp->bio_pblkno;
|
|
TAILQ_REMOVE(&head->queue, bp, bio_queue);
|
|
if (TAILQ_FIRST(&head->queue) == head->switch_point)
|
|
head->switch_point = NULL;
|
|
}
|
|
|
|
static __inline struct buf *
|
|
bufq_first(struct buf_queue_head *head)
|
|
{
|
|
return (TAILQ_FIRST(&head->queue));
|
|
}
|
|
|
|
static __inline struct bio *
|
|
bioq_first(struct bio_queue_head *head)
|
|
{
|
|
return (TAILQ_FIRST(&head->queue));
|
|
}
|
|
|
|
#define BUF_WRITE(bp) VOP_BWRITE((bp)->b_vp, (bp))
|
|
#define BUF_STRATEGY(bp) VOP_STRATEGY((bp)->b_vp, (bp))
|
|
|
|
#endif /* _KERNEL */
|
|
|
|
/*
|
|
* Definitions for the buffer free lists.
|
|
*/
|
|
#define BUFFER_QUEUES 6 /* number of free buffer queues */
|
|
|
|
#define QUEUE_NONE 0 /* on no queue */
|
|
#define QUEUE_LOCKED 1 /* locked buffers */
|
|
#define QUEUE_CLEAN 2 /* non-B_DELWRI buffers */
|
|
#define QUEUE_DIRTY 3 /* B_DELWRI buffers */
|
|
#define QUEUE_EMPTYKVA 4 /* empty buffer headers w/KVA assignment */
|
|
#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; \
|
|
}
|
|
|
|
/*
|
|
* Zero out the bio's data area.
|
|
*/
|
|
#define clrbio(bp) { \
|
|
bzero((bp)->bio_data, (u_int)(bp)->bio_bcount); \
|
|
(bp)->bio_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 int buf_maxio; /* nominal maximum I/O for buffer */
|
|
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;
|
|
extern TAILQ_HEAD(bqueues, buf) bufqueues[BUFFER_QUEUES];
|
|
|
|
struct uio;
|
|
|
|
caddr_t bufhashinit __P((caddr_t));
|
|
void bufinit __P((void));
|
|
void bwillwrite __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 bdirty __P((struct buf *));
|
|
void bundirty __P((struct buf *));
|
|
int bowrite __P((struct buf *));
|
|
void brelse __P((struct buf *));
|
|
void bqrelse __P((struct buf *));
|
|
int vfs_bio_awrite __P((struct buf *));
|
|
struct buf * getpbuf __P((int *));
|
|
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 bufwait __P((struct buf *));
|
|
void bufdone __P((struct buf *));
|
|
void bufdonebio __P((struct bio *));
|
|
|
|
void cluster_callback __P((struct buf *));
|
|
int cluster_read __P((struct vnode *, u_quad_t, daddr_t, long,
|
|
struct ucred *, long, int, struct buf **));
|
|
int cluster_wbuild __P((struct vnode *, long, daddr_t, int));
|
|
void cluster_write __P((struct buf *, u_quad_t, int));
|
|
int physio __P((dev_t dev, struct uio *uio, int ioflag));
|
|
#define physread physio
|
|
#define physwrite physio
|
|
void vfs_bio_set_validclean __P((struct buf *, int base, int size));
|
|
void vfs_bio_clrbuf __P((struct buf *));
|
|
void vfs_busy_pages __P((struct buf *, int clear_modify));
|
|
void vfs_unbusy_pages __P((struct buf *));
|
|
void vwakeup __P((struct buf *));
|
|
void vmapbuf __P((struct buf *));
|
|
void vunmapbuf __P((struct buf *));
|
|
void relpbuf __P((struct buf *, int *));
|
|
void brelvp __P((struct buf *));
|
|
void bgetvp __P((struct vnode *, struct buf *));
|
|
void pbgetvp __P((struct vnode *, struct buf *));
|
|
void pbrelvp __P((struct buf *));
|
|
int allocbuf __P((struct buf *bp, int size));
|
|
void reassignbuf __P((struct buf *, struct vnode *));
|
|
void pbreassignbuf __P((struct buf *, struct vnode *));
|
|
struct buf *trypbuf __P((int *));
|
|
|
|
#endif /* _KERNEL */
|
|
|
|
#endif /* !_SYS_BUF_H_ */
|