/* $OpenBSD: vfs_vnops.c,v 1.19 1998/12/05 17:16:54 csapuntz Exp $ */ /* $NetBSD: vfs_vnops.c,v 1.20 1996/02/04 02:18:41 christos Exp $ */ /* * 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. * * @(#)vfs_vnops.c 8.5 (Berkeley) 12/8/94 */ #include #include #include #include #include #include #include #include #include #include #include #include #include struct fileops vnops = { vn_read, vn_write, vn_ioctl, vn_select, vn_closefile }; /* * Common code for vnode open operations. * Check permissions, and call the VOP_OPEN or VOP_CREATE routine. */ int vn_open(ndp, fmode, cmode) register struct nameidata *ndp; int fmode, cmode; { register struct vnode *vp; register struct proc *p = ndp->ni_cnd.cn_proc; register struct ucred *cred = p->p_ucred; struct vattr va; int error; if ((fmode & (FREAD|FWRITE)) == 0) return (EINVAL); if ((fmode & (O_TRUNC | FWRITE)) == O_TRUNC) return (EINVAL); if (fmode & O_CREAT) { ndp->ni_cnd.cn_nameiop = CREATE; ndp->ni_cnd.cn_flags = LOCKPARENT | LOCKLEAF; if (((fmode & O_EXCL) == 0) && ((fmode & FNOSYMLINK) == 0)) ndp->ni_cnd.cn_flags |= FOLLOW; if ((error = namei(ndp)) != 0) return (error); if (ndp->ni_vp == NULL) { VATTR_NULL(&va); va.va_type = VREG; va.va_mode = cmode; VOP_LEASE(ndp->ni_dvp, p, cred, LEASE_WRITE); error = VOP_CREATE(ndp->ni_dvp, &ndp->ni_vp, &ndp->ni_cnd, &va); if (error) return (error); fmode &= ~O_TRUNC; vp = ndp->ni_vp; } else { VOP_ABORTOP(ndp->ni_dvp, &ndp->ni_cnd); if (ndp->ni_dvp == ndp->ni_vp) vrele(ndp->ni_dvp); else vput(ndp->ni_dvp); ndp->ni_dvp = NULL; vp = ndp->ni_vp; if (fmode & O_EXCL) { error = EEXIST; goto bad; } if ((ndp->ni_vp->v_type == VLNK) & ((fmode & FNOSYMLINK) != 0)) { error = EFTYPE; goto bad; } fmode &= ~O_CREAT; } } else { ndp->ni_cnd.cn_nameiop = LOOKUP; ndp->ni_cnd.cn_flags = FOLLOW | LOCKLEAF; if ((error = namei(ndp)) != 0) return (error); vp = ndp->ni_vp; } if (vp->v_type == VSOCK) { error = EOPNOTSUPP; goto bad; } if ((fmode & O_CREAT) == 0) { if (fmode & FREAD) { if ((error = VOP_ACCESS(vp, VREAD, cred, p)) != 0) goto bad; } if (fmode & FWRITE) { if (vp->v_type == VDIR) { error = EISDIR; goto bad; } if ((error = vn_writechk(vp)) != 0 || (error = VOP_ACCESS(vp, VWRITE, cred, p)) != 0) goto bad; } } if (fmode & O_TRUNC) { VOP_UNLOCK(vp, 0, p); /* XXX */ VOP_LEASE(vp, p, cred, LEASE_WRITE); vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p); /* XXX */ VATTR_NULL(&va); va.va_size = 0; if ((error = VOP_SETATTR(vp, &va, cred, p)) != 0) goto bad; } if ((error = VOP_OPEN(vp, fmode, cred, p)) != 0) goto bad; if (fmode & FWRITE) vp->v_writecount++; return (0); bad: vput(vp); return (error); } /* * Check for write permissions on the specified vnode. * Prototype text segments cannot be written. */ int vn_writechk(vp) register struct vnode *vp; { /* * Disallow write attempts on read-only file systems; * unless the file is a socket or a block or character * device resident on the file system. */ if (vp->v_mount->mnt_flag & MNT_RDONLY) { switch (vp->v_type) { case VREG: case VDIR: case VLNK: return (EROFS); case VNON: case VCHR: case VSOCK: case VFIFO: case VBAD: case VBLK: break; } } /* * If there's shared text associated with * the vnode, try to free it up once. If * we fail, we can't allow writing. */ if ((vp->v_flag & VTEXT) && !vnode_pager_uncache(vp)) return (ETXTBSY); return (0); } /* * Vnode close call */ int vn_close(vp, flags, cred, p) register struct vnode *vp; int flags; struct ucred *cred; struct proc *p; { int error; if (flags & FWRITE) vp->v_writecount--; error = VOP_CLOSE(vp, flags, cred, p); vrele(vp); return (error); } /* * Package up an I/O request on a vnode into a uio and do it. */ int vn_rdwr(rw, vp, base, len, offset, segflg, ioflg, cred, aresid, p) enum uio_rw rw; struct vnode *vp; caddr_t base; int len; off_t offset; enum uio_seg segflg; int ioflg; struct ucred *cred; size_t *aresid; struct proc *p; { struct uio auio; struct iovec aiov; int error; if ((ioflg & IO_NODELOCKED) == 0) vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p); auio.uio_iov = &aiov; auio.uio_iovcnt = 1; aiov.iov_base = base; aiov.iov_len = len; auio.uio_resid = len; auio.uio_offset = offset; auio.uio_segflg = segflg; auio.uio_rw = rw; auio.uio_procp = p; if (rw == UIO_READ) { error = VOP_READ(vp, &auio, ioflg, cred); } else { error = VOP_WRITE(vp, &auio, ioflg, cred); } if (aresid) *aresid = auio.uio_resid; else if (auio.uio_resid && error == 0) error = EIO; if ((ioflg & IO_NODELOCKED) == 0) VOP_UNLOCK(vp, 0, p); return (error); } /* * File table vnode read routine. */ int vn_read(fp, uio, cred) struct file *fp; struct uio *uio; struct ucred *cred; { register struct vnode *vp = (struct vnode *)fp->f_data; int error = 0; size_t count; struct proc *p = uio->uio_procp; VOP_LEASE(vp, uio->uio_procp, cred, LEASE_READ); vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p); uio->uio_offset = fp->f_offset; count = uio->uio_resid; if (vp->v_type != VDIR) error = VOP_READ(vp, uio, (fp->f_flag & FNONBLOCK) ? IO_NDELAY : 0, cred); fp->f_offset += count - uio->uio_resid; VOP_UNLOCK(vp, 0, p); return (error); } /* * File table vnode write routine. */ int vn_write(fp, uio, cred) struct file *fp; struct uio *uio; struct ucred *cred; { register struct vnode *vp = (struct vnode *)fp->f_data; struct proc *p = uio->uio_procp; int error, ioflag = IO_UNIT; size_t count; if (vp->v_type == VREG && (fp->f_flag & O_APPEND)) ioflag |= IO_APPEND; if (fp->f_flag & FNONBLOCK) ioflag |= IO_NDELAY; if ((fp->f_flag & O_FSYNC) || (vp->v_mount && (vp->v_mount->mnt_flag & MNT_SYNCHRONOUS))) ioflag |= IO_SYNC; VOP_LEASE(vp, uio->uio_procp, cred, LEASE_WRITE); vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p); uio->uio_offset = fp->f_offset; count = uio->uio_resid; error = VOP_WRITE(vp, uio, ioflag, cred); if (ioflag & IO_APPEND) fp->f_offset = uio->uio_offset; else fp->f_offset += count - uio->uio_resid; VOP_UNLOCK(vp, 0, p); return (error); } /* * File table vnode stat routine. */ int vn_stat(vp, sb, p) struct vnode *vp; register struct stat *sb; struct proc *p; { struct vattr va; int error; u_short mode; error = VOP_GETATTR(vp, &va, p->p_ucred, p); if (error) return (error); /* * Copy from vattr table */ sb->st_dev = va.va_fsid; sb->st_ino = va.va_fileid; mode = va.va_mode; switch (vp->v_type) { case VREG: mode |= S_IFREG; break; case VDIR: mode |= S_IFDIR; break; case VBLK: mode |= S_IFBLK; break; case VCHR: mode |= S_IFCHR; break; case VLNK: mode |= S_IFLNK; break; case VSOCK: mode |= S_IFSOCK; break; case VFIFO: mode |= S_IFIFO; break; default: return (EBADF); }; sb->st_mode = mode; sb->st_nlink = va.va_nlink; sb->st_uid = va.va_uid; sb->st_gid = va.va_gid; sb->st_rdev = va.va_rdev; sb->st_size = va.va_size; sb->st_atimespec = va.va_atime; sb->st_mtimespec = va.va_mtime; sb->st_ctimespec = va.va_ctime; sb->st_blksize = va.va_blocksize; sb->st_flags = va.va_flags; sb->st_gen = va.va_gen; sb->st_blocks = va.va_bytes / S_BLKSIZE; return (0); } /* * File table vnode ioctl routine. */ int vn_ioctl(fp, com, data, p) struct file *fp; u_long com; caddr_t data; struct proc *p; { register struct vnode *vp = ((struct vnode *)fp->f_data); struct vattr vattr; int error; switch (vp->v_type) { case VREG: case VDIR: if (com == FIONREAD) { error = VOP_GETATTR(vp, &vattr, p->p_ucred, p); if (error) return (error); *(int *)data = vattr.va_size - fp->f_offset; return (0); } if (com == FIONBIO || com == FIOASYNC) /* XXX */ return (0); /* XXX */ /* fall into ... */ default: return (ENOTTY); case VFIFO: case VCHR: case VBLK: error = VOP_IOCTL(vp, com, data, fp->f_flag, p->p_ucred, p); if (error == 0 && com == TIOCSCTTY) { if (p->p_session->s_ttyvp) vrele(p->p_session->s_ttyvp); p->p_session->s_ttyvp = vp; VREF(vp); } return (error); } } /* * File table vnode select routine. */ int vn_select(fp, which, p) struct file *fp; int which; struct proc *p; { return (VOP_SELECT(((struct vnode *)fp->f_data), which, fp->f_flag, fp->f_cred, p)); } /* * Check that the vnode is still valid, and if so * acquire requested lock. */ int vn_lock(vp, flags, p) struct vnode *vp; int flags; struct proc *p; { int error; do { if ((flags & LK_INTERLOCK) == 0) simple_lock(&vp->v_interlock); if (vp->v_flag & VXLOCK) { vp->v_flag |= VXWANT; simple_unlock(&vp->v_interlock); tsleep((caddr_t)vp, PINOD, "vn_lock", 0); error = ENOENT; } else { error = VOP_LOCK(vp, flags | LK_INTERLOCK | LK_CANRECURSE, p); if (error == 0) return (error); } flags &= ~LK_INTERLOCK; } while (flags & LK_RETRY); return (error); } /* * File table vnode close routine. */ int vn_closefile(fp, p) struct file *fp; struct proc *p; { return (vn_close(((struct vnode *)fp->f_data), fp->f_flag, fp->f_cred, p)); }