diff options
Diffstat (limited to 'sys/fs/fifofs/fifo_vnops.c')
-rw-r--r-- | sys/fs/fifofs/fifo_vnops.c | 536 |
1 files changed, 536 insertions, 0 deletions
diff --git a/sys/fs/fifofs/fifo_vnops.c b/sys/fs/fifofs/fifo_vnops.c new file mode 100644 index 0000000..b64f957 --- /dev/null +++ b/sys/fs/fifofs/fifo_vnops.c @@ -0,0 +1,536 @@ +/* + * Copyright (c) 1990, 1993, 1995 + * 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 8.10 (Berkeley) 5/27/95 + * $FreeBSD$ + */ + +#include <sys/param.h> +#include <sys/systm.h> +#include <sys/unistd.h> +#include <sys/kernel.h> +#include <sys/lock.h> +#include <sys/malloc.h> +#include <sys/vnode.h> +#include <sys/socket.h> +#include <sys/socketvar.h> +#include <sys/filio.h> +#include <sys/fcntl.h> +#include <sys/file.h> +#include <sys/poll.h> +#include <sys/un.h> +#include <miscfs/fifofs/fifo.h> + +/* + * 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; +}; + +static int fifo_badop __P((void)); +static int fifo_print __P((struct vop_print_args *)); +static int fifo_lookup __P((struct vop_lookup_args *)); +static int fifo_open __P((struct vop_open_args *)); +static int fifo_close __P((struct vop_close_args *)); +static int fifo_read __P((struct vop_read_args *)); +static int fifo_write __P((struct vop_write_args *)); +static int fifo_ioctl __P((struct vop_ioctl_args *)); +static int fifo_poll __P((struct vop_poll_args *)); +static int fifo_inactive __P((struct vop_inactive_args *)); +static int fifo_bmap __P((struct vop_bmap_args *)); +static int fifo_pathconf __P((struct vop_pathconf_args *)); +static int fifo_advlock __P((struct vop_advlock_args *)); + + +vop_t **fifo_vnodeop_p; +static struct vnodeopv_entry_desc fifo_vnodeop_entries[] = { + { &vop_default_desc, (vop_t *) vop_defaultop }, + { &vop_access_desc, (vop_t *) vop_ebadf }, + { &vop_advlock_desc, (vop_t *) fifo_advlock }, + { &vop_bmap_desc, (vop_t *) fifo_bmap }, + { &vop_close_desc, (vop_t *) fifo_close }, + { &vop_create_desc, (vop_t *) fifo_badop }, + { &vop_getattr_desc, (vop_t *) vop_ebadf }, + { &vop_inactive_desc, (vop_t *) fifo_inactive }, + { &vop_ioctl_desc, (vop_t *) fifo_ioctl }, + { &vop_lease_desc, (vop_t *) vop_null }, + { &vop_link_desc, (vop_t *) fifo_badop }, + { &vop_lookup_desc, (vop_t *) fifo_lookup }, + { &vop_mkdir_desc, (vop_t *) fifo_badop }, + { &vop_mknod_desc, (vop_t *) fifo_badop }, + { &vop_open_desc, (vop_t *) fifo_open }, + { &vop_pathconf_desc, (vop_t *) fifo_pathconf }, + { &vop_poll_desc, (vop_t *) fifo_poll }, + { &vop_print_desc, (vop_t *) fifo_print }, + { &vop_read_desc, (vop_t *) fifo_read }, + { &vop_readdir_desc, (vop_t *) fifo_badop }, + { &vop_readlink_desc, (vop_t *) fifo_badop }, + { &vop_reallocblks_desc, (vop_t *) fifo_badop }, + { &vop_reclaim_desc, (vop_t *) vop_null }, + { &vop_remove_desc, (vop_t *) fifo_badop }, + { &vop_rename_desc, (vop_t *) fifo_badop }, + { &vop_rmdir_desc, (vop_t *) fifo_badop }, + { &vop_setattr_desc, (vop_t *) vop_ebadf }, + { &vop_symlink_desc, (vop_t *) fifo_badop }, + { &vop_write_desc, (vop_t *) fifo_write }, + { NULL, NULL } +}; +static struct vnodeopv_desc fifo_vnodeop_opv_desc = + { &fifo_vnodeop_p, fifo_vnodeop_entries }; + +VNODEOP_SET(fifo_vnodeop_opv_desc); + +int +fifo_vnoperate(ap) + struct vop_generic_args /* { + struct vnodeop_desc *a_desc; + <other random data follows, presumably> + } */ *ap; +{ + return (VOCALL(fifo_vnodeop_p, ap->a_desc->vdesc_offset, ap)); +} + +/* + * Trivial lookup routine that always fails. + */ +/* ARGSUSED */ +static int +fifo_lookup(ap) + struct vop_lookup_args /* { + struct vnode * a_dvp; + struct vnode ** a_vpp; + struct componentname * a_cnp; + } */ *ap; +{ + + *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 */ +static int +fifo_open(ap) + struct vop_open_args /* { + struct vnode *a_vp; + int a_mode; + struct ucred *a_cred; + struct proc *a_p; + } */ *ap; +{ + struct vnode *vp = ap->a_vp; + struct fifoinfo *fip; + struct proc *p = ap->a_p; + struct socket *rso, *wso; + int error; + + if ((fip = vp->v_fifoinfo) == NULL) { + MALLOC(fip, struct fifoinfo *, sizeof(*fip), M_VNODE, M_WAITOK); + vp->v_fifoinfo = fip; + error = socreate(AF_LOCAL, &rso, SOCK_STREAM, 0, ap->a_p); + if (error) { + free(fip, M_VNODE); + vp->v_fifoinfo = NULL; + return (error); + } + fip->fi_readsock = rso; + error = socreate(AF_LOCAL, &wso, SOCK_STREAM, 0, ap->a_p); + if (error) { + (void)soclose(rso); + free(fip, M_VNODE); + vp->v_fifoinfo = NULL; + return (error); + } + fip->fi_writesock = wso; + error = unp_connect2(wso, rso); + if (error) { + (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_snd.sb_lowat = PIPE_BUF; + rso->so_state |= SS_CANTRCVMORE; + } + if (ap->a_mode & FREAD) { + fip->fi_readers++; + if (fip->fi_readers == 1) { + fip->fi_writesock->so_state &= ~SS_CANTSENDMORE; + if (fip->fi_writers > 0) + wakeup((caddr_t)&fip->fi_writers); + } + } + if (ap->a_mode & FWRITE) { + fip->fi_writers++; + if (fip->fi_writers == 1) { + fip->fi_readsock->so_state &= ~SS_CANTRCVMORE; + if (fip->fi_readers > 0) + wakeup((caddr_t)&fip->fi_readers); + } + } + if ((ap->a_mode & FREAD) && (ap->a_mode & O_NONBLOCK) == 0) { + while (fip->fi_writers == 0) { + VOP_UNLOCK(vp, 0, p); + error = tsleep((caddr_t)&fip->fi_readers, + PCATCH | PSOCK, "fifoor", 0); + vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p); + 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, 0, p); + error = tsleep((caddr_t)&fip->fi_writers, + PCATCH | PSOCK, "fifoow", 0); + vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p); + if (error) + goto bad; + } + } + } + return (0); +bad: + VOP_CLOSE(vp, ap->a_mode, ap->a_cred, p); + return (error); +} + +/* + * Vnode op for read + */ +/* ARGSUSED */ +static int +fifo_read(ap) + struct vop_read_args /* { + struct vnode *a_vp; + struct uio *a_uio; + int a_ioflag; + struct ucred *a_cred; + } */ *ap; +{ + struct uio *uio = ap->a_uio; + struct socket *rso = ap->a_vp->v_fifoinfo->fi_readsock; + struct proc *p = uio->uio_procp; + 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, 0, p); + error = soreceive(rso, (struct sockaddr **)0, uio, (struct mbuf **)0, + (struct mbuf **)0, (int *)0); + vn_lock(ap->a_vp, LK_EXCLUSIVE | LK_RETRY, p); + if (ap->a_ioflag & IO_NDELAY) + rso->so_state &= ~SS_NBIO; + return (error); +} + +/* + * Vnode op for write + */ +/* ARGSUSED */ +static int +fifo_write(ap) + struct vop_write_args /* { + struct vnode *a_vp; + struct uio *a_uio; + int a_ioflag; + struct ucred *a_cred; + } */ *ap; +{ + struct socket *wso = ap->a_vp->v_fifoinfo->fi_writesock; + struct proc *p = ap->a_uio->uio_procp; + 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, 0, p); + error = sosend(wso, (struct sockaddr *)0, ap->a_uio, 0, + (struct mbuf *)0, 0, p); + vn_lock(ap->a_vp, LK_EXCLUSIVE | LK_RETRY, p); + if (ap->a_ioflag & IO_NDELAY) + wso->so_state &= ~SS_NBIO; + return (error); +} + +/* + * Device ioctl operation. + */ +/* ARGSUSED */ +static int +fifo_ioctl(ap) + struct vop_ioctl_args /* { + struct vnode *a_vp; + int a_command; + caddr_t a_data; + int a_fflag; + struct ucred *a_cred; + struct proc *a_p; + } */ *ap; +{ + 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 */ +static int +fifo_poll(ap) + struct vop_poll_args /* { + struct vnode *a_vp; + int a_events; + struct ucred *a_cred; + struct proc *a_p; + } */ *ap; +{ + 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_cred, + 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_cred, + ap->a_p); + } + return (revents); +} + +static int +fifo_inactive(ap) + struct vop_inactive_args /* { + struct vnode *a_vp; + struct proc *a_p; + } */ *ap; +{ + + VOP_UNLOCK(ap->a_vp, 0, ap->a_p); + return (0); +} + +/* + * This is a noop, simply returning what one has been given. + */ +static int +fifo_bmap(ap) + struct vop_bmap_args /* { + struct vnode *a_vp; + daddr_t a_bn; + struct vnode **a_vpp; + daddr_t *a_bnp; + int *a_runp; + int *a_runb; + } */ *ap; +{ + + if (ap->a_vpp != NULL) + *ap->a_vpp = ap->a_vp; + if (ap->a_bnp != NULL) + *ap->a_bnp = ap->a_bn; + if (ap->a_runp != NULL) + *ap->a_runp = 0; + if (ap->a_runb != NULL) + *ap->a_runb = 0; + return (0); +} + +/* + * Device close routine + */ +/* ARGSUSED */ +static int +fifo_close(ap) + struct vop_close_args /* { + struct vnode *a_vp; + int a_fflag; + struct ucred *a_cred; + struct proc *a_p; + } */ *ap; +{ + register struct vnode *vp = ap->a_vp; + register struct fifoinfo *fip = vp->v_fifoinfo; + int error1, error2; + + if (ap->a_fflag & FREAD) { + fip->fi_readers--; + if (fip->fi_readers == 0) + socantsendmore(fip->fi_writesock); + } + if (ap->a_fflag & FWRITE) { + fip->fi_writers--; + 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 internal contents of a fifo vnode. + */ +int +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 (0); +} + +/* + * Print out the contents of a fifo vnode. + */ +static int +fifo_print(ap) + struct vop_print_args /* { + struct vnode *a_vp; + } */ *ap; +{ + + printf("tag VT_NON"); + fifo_printinfo(ap->a_vp); + printf("\n"); + return (0); +} + +/* + * Return POSIX pathconf information applicable to fifo's. + */ +int +fifo_pathconf(ap) + struct vop_pathconf_args /* { + struct vnode *a_vp; + int a_name; + int *a_retval; + } */ *ap; +{ + + 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 */ +} + +/* + * Fifo advisory byte-level locks. + */ +/* ARGSUSED */ +static int +fifo_advlock(ap) + struct vop_advlock_args /* { + struct vnode *a_vp; + caddr_t a_id; + int a_op; + struct flock *a_fl; + int a_flags; + } */ *ap; +{ + + return (ap->a_flags & F_FLOCK ? EOPNOTSUPP : EINVAL); +} + +/* + * Fifo bad operation + */ +static int +fifo_badop() +{ + + panic("fifo_badop called"); + /* NOTREACHED */ +} |