/* $NetBSD: fifo_vnops.c,v 1.24 1997/10/09 13:12:01 mycroft Exp $ */ /* * Copyright (c) 1990, 1993 * The Regents of the University of California. All rights reserved. * * 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. * * @(#)fifo_vnops.c 8.4 (Berkeley) 8/10/94 */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * This structure is associated with the FIFO vnode and stores * the state associated with the FIFO. */ struct fifoinfo { struct socket *fi_readsock; struct socket *fi_writesock; long fi_readers; long fi_writers; }; int (**fifo_vnodeop_p) __P((void *)); struct vnodeopv_entry_desc fifo_vnodeop_entries[] = { { &vop_default_desc, vn_default_error }, { &vop_lookup_desc, fifo_lookup }, /* lookup */ { &vop_create_desc, fifo_create }, /* create */ { &vop_mknod_desc, fifo_mknod }, /* mknod */ { &vop_open_desc, fifo_open }, /* open */ { &vop_close_desc, fifo_close }, /* close */ { &vop_access_desc, fifo_access }, /* access */ { &vop_getattr_desc, fifo_getattr }, /* getattr */ { &vop_setattr_desc, fifo_setattr }, /* setattr */ { &vop_read_desc, fifo_read }, /* read */ { &vop_write_desc, fifo_write }, /* write */ { &vop_lease_desc, fifo_lease_check }, /* lease */ { &vop_ioctl_desc, fifo_ioctl }, /* ioctl */ { &vop_poll_desc, fifo_poll }, /* poll */ { &vop_mmap_desc, fifo_mmap }, /* mmap */ { &vop_fsync_desc, fifo_fsync }, /* fsync */ { &vop_seek_desc, fifo_seek }, /* seek */ { &vop_remove_desc, fifo_remove }, /* remove */ { &vop_link_desc, fifo_link }, /* link */ { &vop_rename_desc, fifo_rename }, /* rename */ { &vop_mkdir_desc, fifo_mkdir }, /* mkdir */ { &vop_rmdir_desc, fifo_rmdir }, /* rmdir */ { &vop_symlink_desc, fifo_symlink }, /* symlink */ { &vop_readdir_desc, fifo_readdir }, /* readdir */ { &vop_readlink_desc, fifo_readlink }, /* readlink */ { &vop_abortop_desc, fifo_abortop }, /* abortop */ { &vop_inactive_desc, fifo_inactive }, /* inactive */ { &vop_reclaim_desc, fifo_reclaim }, /* reclaim */ { &vop_lock_desc, fifo_lock }, /* lock */ { &vop_unlock_desc, fifo_unlock }, /* unlock */ { &vop_bmap_desc, fifo_bmap }, /* bmap */ { &vop_strategy_desc, fifo_strategy }, /* strategy */ { &vop_print_desc, fifo_print }, /* print */ { &vop_islocked_desc, fifo_islocked }, /* islocked */ { &vop_pathconf_desc, fifo_pathconf }, /* pathconf */ { &vop_advlock_desc, fifo_advlock }, /* advlock */ { &vop_blkatoff_desc, fifo_blkatoff }, /* blkatoff */ { &vop_valloc_desc, fifo_valloc }, /* valloc */ { &vop_vfree_desc, fifo_vfree }, /* vfree */ { &vop_truncate_desc, fifo_truncate }, /* truncate */ { &vop_update_desc, fifo_update }, /* update */ { &vop_bwrite_desc, fifo_bwrite }, /* bwrite */ { (struct vnodeop_desc*)NULL, (int(*) __P((void *)))NULL } }; struct vnodeopv_desc fifo_vnodeop_opv_desc = { &fifo_vnodeop_p, fifo_vnodeop_entries }; /* * Trivial lookup routine that always fails. */ /* ARGSUSED */ int fifo_lookup(v) void *v; { struct vop_lookup_args /* { struct vnode * a_dvp; struct vnode ** a_vpp; struct componentname * a_cnp; } */ *ap = v; *ap->a_vpp = NULL; return (ENOTDIR); } /* * Open called to set up a new instance of a fifo or * to find an active instance of a fifo. */ /* ARGSUSED */ int fifo_open(v) void *v; { struct vop_open_args /* { struct vnode *a_vp; int a_mode; struct ucred *a_cred; struct proc *a_p; } */ *ap = v; register struct vnode *vp = ap->a_vp; register struct fifoinfo *fip; struct socket *rso, *wso; int error; static const char openstr[] = "fifo"; if ((fip = vp->v_fifoinfo) == NULL) { MALLOC(fip, struct fifoinfo *, sizeof(*fip), M_VNODE, M_WAITOK); vp->v_fifoinfo = fip; if ((error = socreate(AF_LOCAL, &rso, SOCK_STREAM, 0)) != 0) { free(fip, M_VNODE); vp->v_fifoinfo = NULL; return (error); } fip->fi_readsock = rso; if ((error = socreate(AF_LOCAL, &wso, SOCK_STREAM, 0)) != 0) { (void)soclose(rso); free(fip, M_VNODE); vp->v_fifoinfo = NULL; return (error); } fip->fi_writesock = wso; if ((error = unp_connect2(wso, rso)) != 0) { (void)soclose(wso); (void)soclose(rso); free(fip, M_VNODE); vp->v_fifoinfo = NULL; return (error); } fip->fi_readers = fip->fi_writers = 0; wso->so_state |= SS_CANTRCVMORE; rso->so_state |= SS_CANTSENDMORE; } if (ap->a_mode & FREAD) { if (fip->fi_readers++ == 0) { fip->fi_writesock->so_state &= ~SS_CANTSENDMORE; if (fip->fi_writers > 0) wakeup((caddr_t)&fip->fi_writers); } } if (ap->a_mode & FWRITE) { if (fip->fi_writers++ == 0) { fip->fi_readsock->so_state &= ~SS_CANTRCVMORE; if (fip->fi_readers > 0) wakeup((caddr_t)&fip->fi_readers); } } if (ap->a_mode & FREAD) { if (ap->a_mode & O_NONBLOCK) { } else { while (fip->fi_writers == 0) { VOP_UNLOCK(vp); error = tsleep((caddr_t)&fip->fi_readers, PCATCH | PSOCK, openstr, 0); VOP_LOCK(vp); if (error) goto bad; } } } if (ap->a_mode & FWRITE) { if (ap->a_mode & O_NONBLOCK) { if (fip->fi_readers == 0) { error = ENXIO; goto bad; } } else { while (fip->fi_readers == 0) { VOP_UNLOCK(vp); error = tsleep((caddr_t)&fip->fi_writers, PCATCH | PSOCK, openstr, 0); VOP_LOCK(vp); if (error) goto bad; } } } return (0); bad: VOP_CLOSE(vp, ap->a_mode, ap->a_cred, ap->a_p); return (error); } /* * Vnode op for read */ /* ARGSUSED */ int fifo_read(v) void *v; { struct vop_read_args /* { struct vnode *a_vp; struct uio *a_uio; int a_ioflag; struct ucred *a_cred; } */ *ap = v; register struct uio *uio = ap->a_uio; register struct socket *rso = ap->a_vp->v_fifoinfo->fi_readsock; int error, startresid; #ifdef DIAGNOSTIC if (uio->uio_rw != UIO_READ) panic("fifo_read mode"); #endif if (uio->uio_resid == 0) return (0); if (ap->a_ioflag & IO_NDELAY) rso->so_state |= SS_NBIO; startresid = uio->uio_resid; VOP_UNLOCK(ap->a_vp); error = soreceive(rso, (struct mbuf **)0, uio, (struct mbuf **)0, (struct mbuf **)0, (int *)0); VOP_LOCK(ap->a_vp); /* * Clear EOF indication after first such return. */ if (uio->uio_resid == startresid) rso->so_state &= ~SS_CANTRCVMORE; if (ap->a_ioflag & IO_NDELAY) { rso->so_state &= ~SS_NBIO; if (error == EWOULDBLOCK && ap->a_vp->v_fifoinfo->fi_writers == 0) error = 0; } return (error); } /* * Vnode op for write */ /* ARGSUSED */ int fifo_write(v) void *v; { struct vop_write_args /* { struct vnode *a_vp; struct uio *a_uio; int a_ioflag; struct ucred *a_cred; } */ *ap = v; struct socket *wso = ap->a_vp->v_fifoinfo->fi_writesock; int error; #ifdef DIAGNOSTIC if (ap->a_uio->uio_rw != UIO_WRITE) panic("fifo_write mode"); #endif if (ap->a_ioflag & IO_NDELAY) wso->so_state |= SS_NBIO; VOP_UNLOCK(ap->a_vp); error = sosend(wso, (struct mbuf *)0, ap->a_uio, 0, (struct mbuf *)0, 0); VOP_LOCK(ap->a_vp); if (ap->a_ioflag & IO_NDELAY) wso->so_state &= ~SS_NBIO; return (error); } /* * Device ioctl operation. */ /* ARGSUSED */ int fifo_ioctl(v) void *v; { struct vop_ioctl_args /* { struct vnode *a_vp; u_long a_command; caddr_t a_data; int a_fflag; struct ucred *a_cred; struct proc *a_p; } */ *ap = v; struct file filetmp; int error; if (ap->a_command == FIONBIO) return (0); if (ap->a_fflag & FREAD) { filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_readsock; error = soo_ioctl(&filetmp, ap->a_command, ap->a_data, ap->a_p); if (error) return (error); } if (ap->a_fflag & FWRITE) { filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_writesock; error = soo_ioctl(&filetmp, ap->a_command, ap->a_data, ap->a_p); if (error) return (error); } return (0); } /* ARGSUSED */ int fifo_poll(v) void *v; { struct vop_poll_args /* { struct vnode *a_vp; int a_events; struct proc *a_p; } */ *ap = v; struct file filetmp; int revents = 0; if (ap->a_events & (POLLIN | POLLPRI | POLLRDNORM | POLLRDBAND)) { filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_readsock; if (filetmp.f_data) revents |= soo_poll(&filetmp, ap->a_events, ap->a_p); } if (ap->a_events & (POLLOUT | POLLWRNORM | POLLWRBAND)) { filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_writesock; if (filetmp.f_data) revents |= soo_poll(&filetmp, ap->a_events, ap->a_p); } return (revents); } /* * This is a noop, simply returning what one has been given. */ int fifo_bmap(v) void *v; { struct vop_bmap_args /* { struct vnode *a_vp; daddr_t a_bn; struct vnode **a_vpp; daddr_t *a_bnp; } */ *ap = v; if (ap->a_vpp != NULL) *ap->a_vpp = ap->a_vp; if (ap->a_bnp != NULL) *ap->a_bnp = ap->a_bn; return (0); } /* * At the moment we do not do any locking. */ /* ARGSUSED */ int fifo_lock(v) void *v; { return (0); } /* ARGSUSED */ int fifo_unlock(v) void *v; { return (0); } /* * Device close routine */ /* ARGSUSED */ int fifo_close(v) void *v; { struct vop_close_args /* { struct vnode *a_vp; int a_fflag; struct ucred *a_cred; struct proc *a_p; } */ *ap = v; register struct vnode *vp = ap->a_vp; register struct fifoinfo *fip = vp->v_fifoinfo; int error1, error2; if (ap->a_fflag & FREAD) { if (--fip->fi_readers == 0) socantsendmore(fip->fi_writesock); } if (ap->a_fflag & FWRITE) { if (--fip->fi_writers == 0) socantrcvmore(fip->fi_readsock); } if (vp->v_usecount > 1) return (0); error1 = soclose(fip->fi_readsock); error2 = soclose(fip->fi_writesock); FREE(fip, M_VNODE); vp->v_fifoinfo = NULL; if (error1) return (error1); return (error2); } /* * Print out the contents of a fifo vnode. */ int fifo_print(v) void *v; { struct vop_print_args /* { struct vnode *a_vp; } */ *ap = v; printf("tag VT_NON"); fifo_printinfo(ap->a_vp); printf("\n"); return 0; } /* * Print out internal contents of a fifo vnode. */ void fifo_printinfo(vp) struct vnode *vp; { register struct fifoinfo *fip = vp->v_fifoinfo; printf(", fifo with %ld readers and %ld writers", fip->fi_readers, fip->fi_writers); } /* * Return POSIX pathconf information applicable to fifo's. */ int fifo_pathconf(v) void *v; { struct vop_pathconf_args /* { struct vnode *a_vp; int a_name; register_t *a_retval; } */ *ap = v; switch (ap->a_name) { case _PC_LINK_MAX: *ap->a_retval = LINK_MAX; return (0); case _PC_PIPE_BUF: *ap->a_retval = PIPE_BUF; return (0); case _PC_CHOWN_RESTRICTED: *ap->a_retval = 1; return (0); default: return (EINVAL); } /* NOTREACHED */ }