/* * 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 8.9 (Berkeley) 3/30/95 * $FreeBSD: src/sys/sys/buf.h,v 1.88.2.10 2003/01/25 19:02:23 dillon Exp $ * $DragonFly: src/sys/sys/buf2.h,v 1.21 2008/01/28 07:19:06 nth Exp $ */ #ifndef _SYS_BUF2_H_ #define _SYS_BUF2_H_ #ifdef _KERNEL #ifndef _SYS_BUF_H_ #include /* crit_*() functions */ #endif #ifndef _SYS_GLOBALDATA_H_ #include /* curthread */ #endif #ifndef _SYS_THREAD2_H_ #include /* crit_*() functions */ #endif #ifndef _SYS_SPINLOCK2_H_ #include /* crit_*() functions */ #endif #ifndef _SYS_MOUNT_H_ #include #endif #ifndef _SYS_VNODE_H_ #include #endif #ifndef _VM_VM_PAGE_H_ #include #endif /* * Initialize a lock. */ #define BUF_LOCKINIT(bp) \ lockinit(&(bp)->b_lock, buf_wmesg, 0, 0) /* * * Get a lock sleeping non-interruptably until it becomes available. * * XXX lk_wmesg can race, but should not result in any operational issues. */ static __inline int BUF_LOCK(struct buf *bp, int locktype) { bp->b_lock.lk_wmesg = buf_wmesg; return (lockmgr(&(bp)->b_lock, locktype)); } /* * Get a lock sleeping with specified interruptably and timeout. * * XXX lk_timo can race against other entities calling BUF_TIMELOCK, * but will not interfere with entities calling BUF_LOCK since LK_TIMELOCK * will not be set in that case. * * XXX lk_wmesg can race, but should not result in any operational issues. */ static __inline int BUF_TIMELOCK(struct buf *bp, int locktype, char *wmesg, int timo) { bp->b_lock.lk_wmesg = wmesg; bp->b_lock.lk_timo = timo; return (lockmgr(&(bp)->b_lock, locktype | LK_TIMELOCK)); } /* * Release a lock. Only the acquiring process may free the lock unless * it has been handed off to biodone. */ static __inline void BUF_UNLOCK(struct buf *bp) { lockmgr(&(bp)->b_lock, LK_RELEASE); } /* * When initiating asynchronous I/O, change ownership of the lock to the * kernel. Once done, the lock may legally released by biodone. The * original owning process can no longer acquire it recursively, but must * wait until the I/O is completed and the lock has been freed by biodone. */ static __inline void BUF_KERNPROC(struct buf *bp) { lockmgr_kernproc(&(bp)->b_lock); } /* * Find out the number of references to a lock. * * The non-blocking version should only be used for assertions in cases * where the buffer is expected to be owned or otherwise data stable. */ static __inline int BUF_REFCNT(struct buf *bp) { return (lockcount(&(bp)->b_lock)); } static __inline int BUF_REFCNTNB(struct buf *bp) { return (lockcountnb(&(bp)->b_lock)); } /* * Free a buffer lock. */ #define BUF_LOCKFREE(bp) \ if (BUF_REFCNTNB(bp) > 0) \ panic("free locked buf") static __inline void bioq_init(struct bio_queue_head *bioq) { TAILQ_INIT(&bioq->queue); bioq->off_unused = 0; bioq->reorder = 0; bioq->transition = NULL; bioq->bio_unused = NULL; } static __inline void bioq_insert_tail(struct bio_queue_head *bioq, struct bio *bio) { bioq->transition = NULL; TAILQ_INSERT_TAIL(&bioq->queue, bio, bio_act); } static __inline void bioq_remove(struct bio_queue_head *bioq, struct bio *bio) { /* * Adjust read insertion point when removing the bioq. The * bio after the insert point is a write so move backwards * one (NULL will indicate all the reads have cleared). */ if (bio == bioq->transition) bioq->transition = TAILQ_NEXT(bio, bio_act); TAILQ_REMOVE(&bioq->queue, bio, bio_act); } static __inline struct bio * bioq_first(struct bio_queue_head *bioq) { return (TAILQ_FIRST(&bioq->queue)); } static __inline struct bio * bioq_takefirst(struct bio_queue_head *bioq) { struct bio *bp; bp = TAILQ_FIRST(&bioq->queue); if (bp != NULL) bioq_remove(bioq, bp); return (bp); } /* * Adjust buffer cache buffer's activity count. This * works similarly to vm_page->act_count. */ static __inline void buf_act_advance(struct buf *bp) { if (bp->b_act_count > ACT_MAX - ACT_ADVANCE) bp->b_act_count = ACT_MAX; else bp->b_act_count += ACT_ADVANCE; } static __inline void buf_act_decline(struct buf *bp) { if (bp->b_act_count < ACT_DECLINE) bp->b_act_count = 0; else bp->b_act_count -= ACT_DECLINE; } /* * biodeps inlines - used by softupdates and HAMMER. * * All bioops are MPSAFE */ static __inline void buf_dep_init(struct buf *bp) { bp->b_ops = NULL; LIST_INIT(&bp->b_dep); } /* * Precondition: the buffer has some dependencies. * * MPSAFE */ static __inline void buf_deallocate(struct buf *bp) { struct bio_ops *ops = bp->b_ops; KKASSERT(! LIST_EMPTY(&bp->b_dep)); if (ops) ops->io_deallocate(bp); } /* * MPSAFE */ static __inline int buf_countdeps(struct buf *bp, int n) { struct bio_ops *ops = bp->b_ops; int r; if (ops) r = ops->io_countdeps(bp, n); else r = 0; return(r); } /* * MPSAFE */ static __inline void buf_start(struct buf *bp) { struct bio_ops *ops = bp->b_ops; if (ops) ops->io_start(bp); } /* * MPSAFE */ static __inline void buf_complete(struct buf *bp) { struct bio_ops *ops = bp->b_ops; if (ops) ops->io_complete(bp); } /* * MPSAFE */ static __inline int buf_fsync(struct vnode *vp) { struct bio_ops *ops = vp->v_mount->mnt_bioops; int r; if (ops) r = ops->io_fsync(vp); else r = 0; return(r); } /* * MPSAFE */ static __inline void buf_movedeps(struct buf *bp1, struct buf *bp2) { struct bio_ops *ops = bp1->b_ops; if (ops) ops->io_movedeps(bp1, bp2); } /* * MPSAFE */ static __inline int buf_checkread(struct buf *bp) { struct bio_ops *ops = bp->b_ops; if (ops) return(ops->io_checkread(bp)); return(0); } /* * MPSAFE */ static __inline int buf_checkwrite(struct buf *bp) { struct bio_ops *ops = bp->b_ops; if (ops) return(ops->io_checkwrite(bp)); return(0); } /* * Chained biodone. The bio callback was made and the callback function * wishes to chain the biodone. If no BIO's are left we call bpdone() * with elseit=TRUE (asynchronous completion). * * MPSAFE */ static __inline void biodone_chain(struct bio *bio) { if (bio->bio_prev) biodone(bio->bio_prev); else bpdone(bio->bio_buf, 1); } static __inline int bread(struct vnode *vp, off_t loffset, int size, struct buf **bpp) { *bpp = NULL; return(breadnx(vp, loffset, size, NULL, NULL, 0, bpp)); } static __inline int breadn(struct vnode *vp, off_t loffset, int size, off_t *raoffset, int *rabsize, int cnt, struct buf **bpp) { *bpp = NULL; return(breadnx(vp, loffset, size, raoffset, rabsize, cnt, bpp)); } static __inline int cluster_read(struct vnode *vp, off_t filesize, off_t loffset, int blksize, size_t minreq, size_t maxreq, struct buf **bpp) { *bpp = NULL; return(cluster_readx(vp, filesize, loffset, blksize, minreq, maxreq, bpp)); } #endif /* _KERNEL */ #endif /* !_SYS_BUF2_H_ */