X-Git-Url: https://git.subgeniuskitty.com/unix-history/.git/blobdiff_plain/751af33e9bf19486e15c882eea7908c44ba20ca2..a937f8567ba9375553a85507f18042a6faaffaab:/usr/src/sys/kern/vfs_cluster.c diff --git a/usr/src/sys/kern/vfs_cluster.c b/usr/src/sys/kern/vfs_cluster.c index 372644aa47..362ad50350 100644 --- a/usr/src/sys/kern/vfs_cluster.c +++ b/usr/src/sys/kern/vfs_cluster.c @@ -1,61 +1,81 @@ /* - * Copyright (c) 1982 Regents of the University of California. - * All rights reserved. The Berkeley software License Agreement - * specifies the terms and conditions for redistribution. + * Copyright (c) 1982, 1986, 1989 Regents of the University of California. + * All rights reserved. * - * @(#)vfs_cluster.c 6.6 (Berkeley) %G% + * Redistribution and use in source and binary forms are permitted + * provided that the above copyright notice and this paragraph are + * duplicated in all such forms and that any documentation, + * advertising materials, and other materials related to such + * distribution and use acknowledge that the software was developed + * by the University of California, Berkeley. The name of the + * University may not be used to endorse or promote products derived + * from this software without specific prior written permission. + * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED + * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. + * + * @(#)vfs_cluster.c 7.10 (Berkeley) %G% */ -#include "../machine/pte.h" - #include "param.h" -#include "systm.h" -#include "dir.h" #include "user.h" #include "buf.h" -#include "conf.h" -#include "proc.h" -#include "seg.h" -#include "vm.h" +#include "vnode.h" #include "trace.h" +#include "ucred.h" /* * Read in (if necessary) the block and return a buffer pointer. */ -struct buf * -bread(dev, blkno, size) - dev_t dev; +bread(vp, blkno, size, cred, bpp) + struct vnode *vp; daddr_t blkno; int size; + struct ucred *cred; + struct buf **bpp; +#ifdef SECSIZE + long secsize; +#endif SECSIZE { register struct buf *bp; if (size == 0) panic("bread: size 0"); - bp = getblk(dev, blkno, size); - if (bp->b_flags&B_DONE) { - trace(TR_BREADHIT, pack(dev, size), blkno); - return(bp); +#ifdef SECSIZE + bp = getblk(dev, blkno, size, secsize); +#else SECSIZE + *bpp = bp = getblk(vp, blkno, size); +#endif SECSIZE + if (bp->b_flags&(B_DONE|B_DELWRI)) { + trace(TR_BREADHIT, pack(vp->v_mount->m_fsid[0], size), blkno); + return (0); } bp->b_flags |= B_READ; if (bp->b_bcount > bp->b_bufsize) panic("bread"); - (*bdevsw[major(dev)].d_strategy)(bp); - trace(TR_BREADMISS, pack(dev, size), blkno); + if (bp->b_rcred == NOCRED && cred != NOCRED) { + crhold(cred); + bp->b_rcred = cred; + } + VOP_STRATEGY(bp); + trace(TR_BREADMISS, pack(vp->v_mount->m_fsid[0], size), blkno); u.u_ru.ru_inblock++; /* pay for read */ - biowait(bp); - return(bp); + return (biowait(bp)); } /* * Read in the block, like bread, but also start I/O on the * read-ahead block (which is not allocated to the caller) */ -struct buf * -breada(dev, blkno, size, rablkno, rabsize) - dev_t dev; +breada(vp, blkno, size, rablkno, rabsize, cred, bpp) + struct vnode *vp; daddr_t blkno; int size; +#ifdef SECSIZE + long secsize; +#endif SECSIZE daddr_t rablkno; int rabsize; + struct ucred *cred; + struct buf **bpp; { register struct buf *bp, *rabp; @@ -65,34 +85,48 @@ breada(dev, blkno, size, rablkno, rabsize) * a buffer and initiate i/o (getblk checks * for a cache hit). */ - if (!incore(dev, blkno)) { - bp = getblk(dev, blkno, size); - if ((bp->b_flags&B_DONE) == 0) { + if (!incore(vp, blkno)) { + *bpp = bp = getblk(vp, blkno, size); +#endif SECSIZE + if ((bp->b_flags&(B_DONE|B_DELWRI)) == 0) { bp->b_flags |= B_READ; if (bp->b_bcount > bp->b_bufsize) panic("breada"); - (*bdevsw[major(dev)].d_strategy)(bp); - trace(TR_BREADMISS, pack(dev, size), blkno); + if (bp->b_rcred == NOCRED && cred != NOCRED) { + crhold(cred); + bp->b_rcred = cred; + } + VOP_STRATEGY(bp); + trace(TR_BREADMISS, pack(vp->v_mount->m_fsid[0], size), + blkno); u.u_ru.ru_inblock++; /* pay for read */ } else - trace(TR_BREADHIT, pack(dev, size), blkno); + trace(TR_BREADHIT, pack(vp->v_mount->m_fsid[0], size), + blkno); } /* * If there's a read-ahead block, start i/o * on it also (as above). */ - if (rablkno && !incore(dev, rablkno)) { - rabp = getblk(dev, rablkno, rabsize); - if (rabp->b_flags & B_DONE) { + if (rablkno && !incore(vp, rablkno)) { + rabp = getblk(vp, rablkno, rabsize); +#endif SECSIZE + if (rabp->b_flags & (B_DONE|B_DELWRI)) { brelse(rabp); - trace(TR_BREADHITRA, pack(dev, rabsize), blkno); + trace(TR_BREADHITRA, + pack(vp->v_mount->m_fsid[0], rabsize), blkno); } else { rabp->b_flags |= B_READ|B_ASYNC; if (rabp->b_bcount > rabp->b_bufsize) panic("breadrabp"); - (*bdevsw[major(dev)].d_strategy)(rabp); - trace(TR_BREADMISSRA, pack(dev, rabsize), rablock); + if (bp->b_rcred == NOCRED && cred != NOCRED) { + crhold(cred); + bp->b_rcred = cred; + } + VOP_STRATEGY(rabp); + trace(TR_BREADMISSRA, + pack(vp->v_mount->m_fsid[0], rabsize), rablock); u.u_ru.ru_inblock++; /* pay in advance */ } } @@ -103,9 +137,11 @@ breada(dev, blkno, size, rablkno, rabsize) * above, and just wait for it. */ if (bp == NULL) - return (bread(dev, blkno, size)); - biowait(bp); - return (bp); +#ifdef SECSIZE + return (bread(dev, blkno, size, secsize)); +#else SECSIZE + return (bread(vp, blkno, size, cred, bpp)); + return (biowait(bp)); } /* @@ -115,16 +151,18 @@ breada(dev, blkno, size, rablkno, rabsize) bwrite(bp) register struct buf *bp; { - register flag; + register int flag; + int error; flag = bp->b_flags; bp->b_flags &= ~(B_READ | B_DONE | B_ERROR | B_DELWRI); if ((flag&B_DELWRI) == 0) u.u_ru.ru_oublock++; /* noone paid yet */ - trace(TR_BWRITE, pack(bp->b_dev, bp->b_bcount), bp->b_blkno); + trace(TR_BWRITE, + pack(bp->b_vp->v_mount->m_fsid[0], bp->b_bcount), bp->b_blkno); if (bp->b_bcount > bp->b_bufsize) panic("bwrite"); - (*bdevsw[major(bp->b_dev)].d_strategy)(bp); + VOP_STRATEGY(bp); /* * If the write was synchronous, then await i/o completion. @@ -132,10 +170,13 @@ bwrite(bp) * the q of blocks awaiting i/o completion status. */ if ((flag&B_ASYNC) == 0) { - biowait(bp); + error = biowait(bp); brelse(bp); - } else if (flag & B_DELWRI) + } else if (flag & B_DELWRI) { bp->b_flags |= B_AGE; + error = 0; + } + return (error); } /* @@ -149,17 +190,25 @@ bwrite(bp) bdwrite(bp) register struct buf *bp; { - register int flags; if ((bp->b_flags&B_DELWRI) == 0) u.u_ru.ru_oublock++; /* noone paid yet */ - flags = bdevsw[major(bp->b_dev)].d_flags; - if(flags & B_TAPE) +#ifdef notdef + /* + * This does not work for buffers associated with + * vnodes that are remote - they have no dev. + * Besides, we don't use bio with tapes, so rather + * than develop a fix, we just ifdef this out for now. + */ + if (bdevsw[major(bp->b_dev)].d_flags & B_TAPE) bawrite(bp); else { bp->b_flags |= B_DELWRI | B_DONE; brelse(bp); } +#endif + bp->b_flags |= B_DELWRI | B_DONE; + brelse(bp); } /* @@ -170,7 +219,7 @@ bawrite(bp) { bp->b_flags |= B_ASYNC; - bwrite(bp); + (void) bwrite(bp); } /* @@ -182,7 +231,8 @@ brelse(bp) register struct buf *flist; register s; - trace(TR_BRELSE, pack(bp->b_dev, bp->b_bufsize), bp->b_blkno); + trace(TR_BRELSE, + pack(bp->b_vp->v_mount->m_fsid[0], bp->b_bufsize), bp->b_blkno); /* * If someone's waiting for the buffer, or * is waiting for a buffer wake 'em up. @@ -193,16 +243,19 @@ brelse(bp) bfreelist[0].b_flags &= ~B_WANTED; wakeup((caddr_t)bfreelist); } + if (bp->b_flags & B_NOCACHE) { + bp->b_flags |= B_INVAL; + } if (bp->b_flags&B_ERROR) if (bp->b_flags & B_LOCKED) bp->b_flags &= ~B_ERROR; /* try again later */ else - bp->b_dev = NODEV; /* no assoc */ + brelvp(bp); /* no assoc */ /* * Stick the buffer back on a free list. */ - s = spl6(); + s = splbio(); if (bp->b_bufsize <= 0) { /* block has no buffer ... put at front of unused buffer list */ flist = &bfreelist[BQ_EMPTY]; @@ -220,7 +273,7 @@ brelse(bp) flist = &bfreelist[BQ_LRU]; binstailfree(bp, flist); } - bp->b_flags &= ~(B_WANTED|B_BUSY|B_ASYNC|B_AGE); + bp->b_flags &= ~(B_WANTED|B_BUSY|B_ASYNC|B_AGE|B_NOCACHE); splx(s); } @@ -228,30 +281,36 @@ brelse(bp) * See if the block is associated with some buffer * (mainly to avoid getting hung up on a wait in breada) */ -incore(dev, blkno) - dev_t dev; +incore(vp, blkno) + struct vnode *vp; daddr_t blkno; { register struct buf *bp; register struct buf *dp; - dp = BUFHASH(dev, blkno); + dp = BUFHASH(vp, blkno); for (bp = dp->b_forw; bp != dp; bp = bp->b_forw) - if (bp->b_blkno == blkno && bp->b_dev == dev && + if (bp->b_blkno == blkno && bp->b_vp == vp && (bp->b_flags & B_INVAL) == 0) return (1); return (0); } -struct buf * -baddr(dev, blkno, size) - dev_t dev; +baddr(vp, blkno, size, cred, bpp) + struct vnode *vp; daddr_t blkno; int size; + struct ucred *cred; + struct buf **bpp; +#ifdef SECSIZE + long secsize; +#endif SECSIZE { - if (incore(dev, blkno)) - return (bread(dev, blkno, size)); + if (incore(vp, blkno)) + return (bread(vp, blkno, size, cred, bpp)); + *bpp = 0; +#endif SECSIZE return (0); } @@ -260,19 +319,34 @@ baddr(dev, blkno, size) * block is already associated, return it; otherwise search * for the oldest non-busy buffer and reassign it. * + * If we find the buffer, but it is dirty (marked DELWRI) and + * its size is changing, we must write it out first. When the + * buffer is shrinking, the write is done by brealloc to avoid + * losing the unwritten data. When the buffer is growing, the + * write is done by getblk, so that bread will not read stale + * disk data over the modified data in the buffer. + * * We use splx here because this routine may be called * on the interrupt stack during a dump, and we don't * want to lower the ipl back to 0. */ struct buf * -getblk(dev, blkno, size) - dev_t dev; +#ifdef SECSIZE +getblk(dev, blkno, size, secsize) +#else SECSIZE +getblk(vp, blkno, size) + register struct vnode *vp; daddr_t blkno; int size; +#ifdef SECSIZE + long secsize; +#endif SECSIZE { register struct buf *bp, *dp; int s; + if (size > MAXBSIZE) + panic("getblk: size too big"); /* * To prevent overflow of 32-bit ints when converting block * numbers to byte offsets, blknos > 2^32 / DEV_BSIZE are set @@ -288,13 +362,13 @@ getblk(dev, blkno, size) * the buffer is in use for i/o, then we wait until * the i/o has completed. */ - dp = BUFHASH(dev, blkno); + dp = BUFHASH(vp, blkno); loop: for (bp = dp->b_forw; bp != dp; bp = bp->b_forw) { - if (bp->b_blkno != blkno || bp->b_dev != dev || + if (bp->b_blkno != blkno || bp->b_vp != vp || bp->b_flags&B_INVAL) continue; - s = spl6(); + s = splbio(); if (bp->b_flags&B_BUSY) { bp->b_flags |= B_WANTED; sleep((caddr_t)bp, PRIBIO+1); @@ -303,23 +377,38 @@ loop: } splx(s); notavail(bp); + if (bp->b_bcount != size) { + if (bp->b_bcount < size && (bp->b_flags&B_DELWRI)) { + bp->b_flags &= ~B_ASYNC; + (void) bwrite(bp); + goto loop; + } + if (brealloc(bp, size) == 0) + goto loop; + } if (bp->b_bcount != size && brealloc(bp, size) == 0) goto loop; bp->b_flags |= B_CACHE; - return(bp); + return (bp); } - if (major(dev) >= nblkdev) - panic("blkdev"); bp = getnewbuf(); bfree(bp); bremhash(bp); - binshash(bp, dp); - bp->b_dev = dev; + if (bp->b_vp) + brelvp(bp); + VREF(vp); + bp->b_vp = vp; + bp->b_dev = vp->v_rdev; +#ifdef SECSIZE + bp->b_blksize = secsize; +#endif SECSIZE bp->b_blkno = blkno; bp->b_error = 0; + bp->b_resid = 0; + binshash(bp, dp); if (brealloc(bp, size) == 0) goto loop; - return(bp); + return (bp); } /* @@ -332,18 +421,24 @@ geteblk(size) { register struct buf *bp, *flist; + if (size > MAXBSIZE) + panic("geteblk: size too big"); loop: bp = getnewbuf(); bp->b_flags |= B_INVAL; bfree(bp); bremhash(bp); flist = &bfreelist[BQ_AGE]; - binshash(bp, flist); - bp->b_dev = (dev_t)NODEV; + brelvp(bp); +#ifdef SECSIZE + bp->b_blksize = DEV_BSIZE; +#endif SECSIZE bp->b_error = 0; + bp->b_resid = 0; + binshash(bp, flist); if (brealloc(bp, size) == 0) goto loop; - return(bp); + return (bp); } /* @@ -360,14 +455,14 @@ brealloc(bp, size) int s; /* - * First need to make sure that all overlaping previous I/O + * First need to make sure that all overlapping previous I/O * is dispatched with. */ if (size == bp->b_bcount) return (1); if (size < bp->b_bcount) { if (bp->b_flags & B_DELWRI) { - bwrite(bp); + (void) bwrite(bp); return (0); } if (bp->b_flags & B_LOCKED) @@ -375,10 +470,11 @@ brealloc(bp, size) return (allocbuf(bp, size)); } bp->b_flags &= ~B_DONE; - if (bp->b_dev == NODEV) + if (bp->b_vp == (struct vnode *)0) return (allocbuf(bp, size)); - trace(TR_BREALLOC, pack(bp->b_dev, size), bp->b_blkno); + trace(TR_BREALLOC, + pack(bp->b_vp->v_mount->m_fsid[0], size), bp->b_blkno); /* * Search cache for any buffers that overlap the one that we * are trying to allocate. Overlapping buffers must be marked @@ -388,17 +484,26 @@ brealloc(bp, size) * when two buffer are trying to get the same set of disk blocks. */ start = bp->b_blkno; +#ifdef SECSIZE + last = start + size/bp->b_blksize - 1; +#else SECSIZE last = start + btodb(size) - 1; - dp = BUFHASH(bp->b_dev, bp->b_blkno); +#endif SECSIZE + dp = BUFHASH(bp->b_vp, bp->b_blkno); loop: for (ep = dp->b_forw; ep != dp; ep = ep->b_forw) { - if (ep == bp || ep->b_dev != bp->b_dev || (ep->b_flags&B_INVAL)) + if (ep == bp || ep->b_vp != bp->b_vp || + (ep->b_flags & B_INVAL)) continue; /* look for overlap */ if (ep->b_bcount == 0 || ep->b_blkno > last || +#ifdef SECSIZE + ep->b_blkno + ep->b_bcount/ep->b_blksize <= start) +#else SECSIZE ep->b_blkno + btodb(ep->b_bcount) <= start) +#endif SECSIZE continue; - s = spl6(); + s = splbio(); if (ep->b_flags&B_BUSY) { ep->b_flags |= B_WANTED; sleep((caddr_t)ep, PRIBIO+1); @@ -408,7 +513,7 @@ loop: splx(s); notavail(ep); if (ep->b_flags & B_DELWRI) { - bwrite(ep); + (void) bwrite(ep); goto loop; } ep->b_flags |= B_INVAL; @@ -426,10 +531,11 @@ struct buf * getnewbuf() { register struct buf *bp, *dp; + register struct ucred *cred; int s; loop: - s = spl6(); + s = splbio(); for (dp = &bfreelist[BQ_AGE]; dp > bfreelist; dp--) if (dp->av_forw != dp) break; @@ -443,11 +549,22 @@ loop: bp = dp->av_forw; notavail(bp); if (bp->b_flags & B_DELWRI) { - bp->b_flags |= B_ASYNC; - bwrite(bp); + (void) bawrite(bp); goto loop; } - trace(TR_BRELSE, pack(bp->b_dev, bp->b_bufsize), bp->b_blkno); + trace(TR_BRELSE, + pack(bp->b_vp->v_mount->m_fsid[0], bp->b_bufsize), bp->b_blkno); + brelvp(bp); + if (bp->b_rcred != NOCRED) { + cred = bp->b_rcred; + bp->b_rcred = NOCRED; + crfree(cred); + } + if (bp->b_wcred != NOCRED) { + cred = bp->b_wcred; + bp->b_wcred = NOCRED; + crfree(cred); + } bp->b_flags = B_BUSY; return (bp); } @@ -461,12 +578,19 @@ biowait(bp) { int s; - s = spl6(); - while ((bp->b_flags&B_DONE)==0) + s = splbio(); + while ((bp->b_flags & B_DONE) == 0) sleep((caddr_t)bp, PRIBIO); splx(s); - if (u.u_error == 0) /* XXX */ - u.u_error = geterror(bp); + /* + * Pick up the device's error number and pass it to the user; + * if there is an error but the number is 0 set a generalized code. + */ + if ((bp->b_flags & B_ERROR) == 0) + return (0); + if (bp->b_error) + return (bp->b_error); + return (EIO); } /* @@ -482,6 +606,8 @@ biodone(bp) if (bp->b_flags & B_DONE) panic("dup biodone"); bp->b_flags |= B_DONE; + if ((bp->b_flags & B_READ) == 0) + bp->b_dirtyoff = bp->b_dirtyend = 0; if (bp->b_flags & B_CALL) { bp->b_flags &= ~B_CALL; (*bp->b_iodone)(bp); @@ -496,30 +622,48 @@ biodone(bp) } /* - * Insure that no part of a specified block is in an incore buffer. + * Ensure that no part of a specified block is in an incore buffer. +#ifdef SECSIZE + * "size" is given in device blocks (the units of b_blkno). +#endif SECSIZE +#ifdef SECSIZE + * "size" is given in device blocks (the units of b_blkno). +#endif SECSIZE */ -blkflush(dev, blkno, size) - dev_t dev; +blkflush(vp, blkno, size) + struct vnode *vp; daddr_t blkno; +#ifdef SECSIZE + int size; +#else SECSIZE long size; +#endif SECSIZE { register struct buf *ep; struct buf *dp; daddr_t start, last; - int s; + int s, error, allerrors = 0; start = blkno; +#ifdef SECSIZE + last = start + size - 1; +#else SECSIZE last = start + btodb(size) - 1; - dp = BUFHASH(dev, blkno); +#endif SECSIZE + dp = BUFHASH(vp, blkno); loop: for (ep = dp->b_forw; ep != dp; ep = ep->b_forw) { - if (ep->b_dev != dev || (ep->b_flags&B_INVAL)) + if (ep->b_vp != vp || (ep->b_flags & B_INVAL)) continue; /* look for overlap */ if (ep->b_bcount == 0 || ep->b_blkno > last || +#ifdef SECSIZE + ep->b_blkno + ep->b_bcount / ep->b_blksize <= start) +#else SECSIZE ep->b_blkno + btodb(ep->b_bcount) <= start) +#endif SECSIZE continue; - s = spl6(); + s = splbio(); if (ep->b_flags&B_BUSY) { ep->b_flags |= B_WANTED; sleep((caddr_t)ep, PRIBIO+1); @@ -529,80 +673,96 @@ loop: if (ep->b_flags & B_DELWRI) { splx(s); notavail(ep); - bwrite(ep); + if (error = bwrite(ep)) + allerrors = error; goto loop; } splx(s); } + return (allerrors); } /* - * Make sure all write-behind blocks - * on dev (or NODEV for all) - * are flushed out. - * (from umount and update) + * Make sure all write-behind blocks associated + * with mount point are flushed out (from sync). */ -bflush(dev) - dev_t dev; +bflush(mountp) + struct mount *mountp; { register struct buf *bp; register struct buf *flist; int s; loop: - s = spl6(); - for (flist = bfreelist; flist < &bfreelist[BQ_EMPTY]; flist++) - for (bp = flist->av_forw; bp != flist; bp = bp->av_forw) { - if ((bp->b_flags & B_DELWRI) == 0) - continue; - if (dev == NODEV || dev == bp->b_dev) { - bp->b_flags |= B_ASYNC; - notavail(bp); - bwrite(bp); - splx(s); - goto loop; + s = splbio(); + for (flist = bfreelist; flist < &bfreelist[BQ_EMPTY]; flist++) { + for (bp = flist->av_forw; bp != flist; bp = bp->av_forw) { + if ((bp->b_flags & B_BUSY)) + continue; + if ((bp->b_flags & B_DELWRI) == 0) + continue; + if (bp->b_vp && bp->b_vp->v_mount == mountp) { + notavail(bp); + (void) bawrite(bp); + splx(s); + goto loop; + } } } splx(s); } -/* - * Pick up the device's error number and pass it to the user; - * if there is an error but the number is 0 set a generalized - * code. Actually the latter is always true because devices - * don't yet return specific errors. - */ -geterror(bp) - register struct buf *bp; -{ - int error = 0; - - if (bp->b_flags&B_ERROR) - if ((error = bp->b_error)==0) - return (EIO); - return (error); -} - /* * Invalidate in core blocks belonging to closed or umounted filesystem * - * This is not nicely done at all - the buffer ought to be removed from the - * hash chains & have its dev/blkno fields clobbered, but unfortunately we - * can't do that here, as it is quite possible that the block is still - * being used for i/o. Eventually, all disc drivers should be forced to - * have a close routine, which ought ensure that the queue is empty, then - * properly flush the queues. Until that happy day, this suffices for - * correctness. ... kre + * We walk through the buffer pool and invalidate any buffers for the + * indicated mount point. Normally this routine is preceeded by a bflush + * call, so that on a quiescent filesystem there will be no dirty + * buffers when we are done. We return the count of dirty buffers when + * we are finished. */ -binval(dev) - dev_t dev; +binval(mountp) + struct mount *mountp; { register struct buf *bp; register struct bufhd *hp; + int s, dirty = 0; #define dp ((struct buf *)hp) - for (hp = bufhash; hp < &bufhash[BUFHSZ]; hp++) - for (bp = dp->b_forw; bp != dp; bp = bp->b_forw) - if (bp->b_dev == dev) - bp->b_flags |= B_INVAL; +loop: + s = splbio(); + for (hp = bufhash; hp < &bufhash[BUFHSZ]; hp++) { + for (bp = dp->b_forw; bp != dp; bp = bp->b_forw) { + if (bp->b_vp == NULL || bp->b_vp->v_mount != mountp) + continue; + if (bp->b_flags & B_BUSY) { + bp->b_flags |= B_WANTED; + sleep((caddr_t)bp, PRIBIO+1); + splx(s); + goto loop; + } + notavail(bp); + if (bp->b_flags & B_DELWRI) { + (void) bawrite(bp); + dirty++; + continue; + } + bp->b_flags |= B_INVAL; + brelvp(bp); + brelse(bp); + } + } + return (dirty); +} + +brelvp(bp) + struct buf *bp; +{ + struct vnode *vp; + + if (bp->b_vp == (struct vnode *) 0) + return; + vp = bp->b_vp; + bp->b_vp = (struct vnode *) 0; + vrele(vp); }