From 1e32f0021ea3509f5552d7a50ae07e37035fed6d Mon Sep 17 00:00:00 2001 From: alc Date: Fri, 26 Mar 1999 20:25:21 +0000 Subject: Changed vn_read/write such that fp->f_offset isn't touched if uio->uio_offset != -1. This fixes a problem with aio_read/write and permits a straightforward implementation of pread/pwrite. PR: kern/8669 Submitted by: John Plevyak Reviewed by: Matthew Dillon --- sys/kern/vfs_vnops.c | 19 +++++++++++++++---- 1 file changed, 15 insertions(+), 4 deletions(-) (limited to 'sys/kern/vfs_vnops.c') diff --git a/sys/kern/vfs_vnops.c b/sys/kern/vfs_vnops.c index b9242b3..708c388d 100644 --- a/sys/kern/vfs_vnops.c +++ b/sys/kern/vfs_vnops.c @@ -36,7 +36,7 @@ * SUCH DAMAGE. * * @(#)vfs_vnops.c 8.2 (Berkeley) 1/21/94 - * $Id: vfs_vnops.c,v 1.62 1999/01/20 14:49:11 eivind Exp $ + * $Id: vfs_vnops.c,v 1.63 1999/01/30 12:21:49 phk Exp $ */ #include @@ -284,13 +284,18 @@ vn_read(fp, uio, cred) VOP_LEASE(vp, p, cred, LEASE_READ); vn_lock(vp, LK_SHARED | LK_NOPAUSE | LK_RETRY, p); - if (uio->uio_offset == -1) - uio->uio_offset = fp->f_offset; - count = uio->uio_resid; + flag = 0; if (fp->f_flag & FNONBLOCK) flag |= IO_NDELAY; + if (uio->uio_offset != -1) { + error = VOP_READ(vp, uio, flag, cred); + goto out; + } + uio->uio_offset = fp->f_offset; + count = uio->uio_resid; + /* * Sequential read heuristic. * If we have been doing sequential input, @@ -321,6 +326,7 @@ vn_read(fp, uio, cred) error = VOP_READ(vp, uio, flag, cred); fp->f_offset += count - uio->uio_resid; fp->f_nextread = fp->f_offset; +out: VOP_UNLOCK(vp, 0, p); return (error); } @@ -347,6 +353,10 @@ vn_write(fp, uio, cred) ioflag |= IO_SYNC; VOP_LEASE(vp, p, cred, LEASE_WRITE); vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p); + if (uio->uio_offset != -1) { + error = VOP_WRITE(vp, uio, ioflag, cred); + goto out; + } uio->uio_offset = fp->f_offset; count = uio->uio_resid; error = VOP_WRITE(vp, uio, ioflag, cred); @@ -354,6 +364,7 @@ vn_write(fp, uio, cred) fp->f_offset = uio->uio_offset; else fp->f_offset += count - uio->uio_resid; +out: VOP_UNLOCK(vp, 0, p); return (error); } -- cgit v1.1