diff options
Diffstat (limited to 'sys/kern/vfs_subr.c')
| -rw-r--r-- | sys/kern/vfs_subr.c | 89 |
1 files changed, 88 insertions, 1 deletions
diff --git a/sys/kern/vfs_subr.c b/sys/kern/vfs_subr.c index 54d247e..a630e1e 100644 --- a/sys/kern/vfs_subr.c +++ b/sys/kern/vfs_subr.c @@ -36,7 +36,7 @@ * SUCH DAMAGE. * * @(#)vfs_subr.c 8.31 (Berkeley) 5/26/95 - * $Id: vfs_subr.c,v 1.139 1998/03/14 02:55:01 tegge Exp $ + * $Id: vfs_subr.c,v 1.140 1998/03/14 19:50:36 dyson Exp $ */ /* @@ -113,8 +113,10 @@ SYSCTL_INT(_debug, OID_AUTO, freevnodes, CTLFLAG_RD, &freevnodes, 0, ""); int vfs_ioopt = 0; #ifdef REALLYBADBUG +#ifdef ENABLE_VFS_IOOPT SYSCTL_INT(_vfs, OID_AUTO, ioopt, CTLFLAG_RW, &vfs_ioopt, 0, ""); #endif +#endif struct mntlist mountlist; /* mounted filesystem list */ struct simplelock mountlist_slock; @@ -631,6 +633,7 @@ vinvalbuf(vp, flags, cred, p, slpflag, slptimeo) break; } bp->b_flags |= (B_INVAL|B_NOCACHE|B_RELBUF); + bp->b_flags &= ~B_ASYNC; brelse(bp); } } @@ -664,6 +667,90 @@ vinvalbuf(vp, flags, cred, p, slpflag, slptimeo) } /* + * Truncate a file's buffer and pages to a specified length. This + * is in lieu of the old vinvalbuf mechanism, which performed unneeded + * sync activity. + */ +int +vtruncbuf(vp, cred, p, length, blksize) + register struct vnode *vp; + struct ucred *cred; + struct proc *p; + off_t length; + int blksize; +{ + register struct buf *bp; + struct buf *nbp, *blist; + int s, error, anyfreed; + vm_object_t object; + int trunclbn; + + /* + * Round up to the *next* lbn. + */ + trunclbn = ((length + blksize - 1) / blksize) * blksize; + + s = splbio(); +restart: + anyfreed = 1; + for (;anyfreed;) { + anyfreed = 0; + for ( bp = LIST_FIRST(&vp->v_cleanblkhd); bp; bp = nbp) { + + nbp = LIST_NEXT(bp, b_vnbufs); + + if (bp->b_lblkno >= trunclbn) { + if (bp->b_flags & B_BUSY) { + bp->b_flags |= B_WANTED; + tsleep((caddr_t) bp, PRIBIO, "vtrb1", 0); + nbp = bp; + } else { + bremfree(bp); + bp->b_flags |= (B_BUSY|B_INVAL|B_NOCACHE|B_RELBUF); + bp->b_flags &= ~B_ASYNC; + brelse(bp); + anyfreed = 1; + } + if (nbp && + ((LIST_NEXT(nbp, b_vnbufs) == NOLIST) || (nbp->b_vp != vp) || + (nbp->b_flags & B_DELWRI))) { + goto restart; + } + } + } + + for (bp = LIST_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) { + + nbp = LIST_NEXT(bp, b_vnbufs); + + if (bp->b_lblkno >= trunclbn) { + if (bp->b_flags & B_BUSY) { + bp->b_flags |= B_WANTED; + tsleep((caddr_t) bp, PRIBIO, "vtrb2", 0); + nbp = bp; + } else { + bremfree(bp); + bp->b_flags |= (B_BUSY|B_INVAL|B_NOCACHE|B_RELBUF); + bp->b_flags &= ~B_ASYNC; + brelse(bp); + anyfreed = 1; + } + if (nbp && + ((LIST_NEXT(nbp, b_vnbufs) == NOLIST) || (nbp->b_vp != vp) || + (nbp->b_flags & B_DELWRI) == 0)) { + goto restart; + } + } + } + } + splx(s); + + vnode_pager_setsize(vp, length); + + return (0); +} + +/* * Associate a buffer with a vnode. */ void |
