/* * Copyright (c) 1992, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software donated to Berkeley by * Jan-Simon Pendry. * * 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. * * @(#)fdesc_vnops.c 8.9 (Berkeley) 1/21/94 * * $Id: fdesc_vnops.c,v 1.42 1999/05/31 11:27:49 phk Exp $ */ /* * /dev/fd Filesystem */ #include #include #include #include /* boottime */ #include #include #include #include #include #include #include #include #include #include #include extern struct cdevsw ctty_cdevsw; #define cttyvp(p) ((p)->p_flag & P_CONTROLT ? (p)->p_session->s_ttyvp : NULL) #define FDL_WANT 0x01 #define FDL_LOCKED 0x02 static int fdcache_lock; static vop_t **fdesc_vnodeop_p; dev_t devctty; #if (FD_STDIN != FD_STDOUT-1) || (FD_STDOUT != FD_STDERR-1) FD_STDIN, FD_STDOUT, FD_STDERR must be a sequence n, n+1, n+2 #endif #define NFDCACHE 4 #define FD_NHASH(ix) \ (&fdhashtbl[(ix) & fdhash]) static LIST_HEAD(fdhashhead, fdescnode) *fdhashtbl; static u_long fdhash; static int fdesc_attr __P((int fd, struct vattr *vap, struct ucred *cred, struct proc *p)); static int fdesc_badop __P((void)); static int fdesc_getattr __P((struct vop_getattr_args *ap)); static int fdesc_inactive __P((struct vop_inactive_args *ap)); static int fdesc_ioctl __P((struct vop_ioctl_args *ap)); static int fdesc_lookup __P((struct vop_lookup_args *ap)); static int fdesc_open __P((struct vop_open_args *ap)); static int fdesc_print __P((struct vop_print_args *ap)); static int fdesc_read __P((struct vop_read_args *ap)); static int fdesc_readdir __P((struct vop_readdir_args *ap)); static int fdesc_readlink __P((struct vop_readlink_args *ap)); static int fdesc_reclaim __P((struct vop_reclaim_args *ap)); static int fdesc_poll __P((struct vop_poll_args *ap)); static int fdesc_setattr __P((struct vop_setattr_args *ap)); static int fdesc_write __P((struct vop_write_args *ap)); /* * Initialise cache headers */ int fdesc_init(vfsp) struct vfsconf *vfsp; { devctty = NODEV; fdhashtbl = hashinit(NFDCACHE, M_CACHE, &fdhash); return (0); } int fdesc_allocvp(ftype, ix, mp, vpp) fdntype ftype; int ix; struct mount *mp; struct vnode **vpp; { struct proc *p = curproc; /* XXX */ struct fdhashhead *fc; struct fdescnode *fd; int error = 0; fc = FD_NHASH(ix); loop: for (fd = fc->lh_first; fd != 0; fd = fd->fd_hash.le_next) { if (fd->fd_ix == ix && fd->fd_vnode->v_mount == mp) { if (vget(fd->fd_vnode, 0, p)) goto loop; *vpp = fd->fd_vnode; return (error); } } /* * otherwise lock the array while we call getnewvnode * since that can block. */ if (fdcache_lock & FDL_LOCKED) { fdcache_lock |= FDL_WANT; (void) tsleep((caddr_t) &fdcache_lock, PINOD, "fdalvp", 0); goto loop; } fdcache_lock |= FDL_LOCKED; /* * Do the MALLOC before the getnewvnode since doing so afterward * might cause a bogus v_data pointer to get dereferenced * elsewhere if MALLOC should block. */ MALLOC(fd, struct fdescnode *, sizeof(struct fdescnode), M_TEMP, M_WAITOK); error = getnewvnode(VT_FDESC, mp, fdesc_vnodeop_p, vpp); if (error) { FREE(fd, M_TEMP); goto out; } (*vpp)->v_data = fd; fd->fd_vnode = *vpp; fd->fd_type = ftype; fd->fd_fd = -1; fd->fd_link = 0; fd->fd_ix = ix; LIST_INSERT_HEAD(fc, fd, fd_hash); out:; fdcache_lock &= ~FDL_LOCKED; if (fdcache_lock & FDL_WANT) { fdcache_lock &= ~FDL_WANT; wakeup((caddr_t) &fdcache_lock); } return (error); } /* * vp is the current namei directory * ndp is the name to locate in that directory... */ static int fdesc_lookup(ap) struct vop_lookup_args /* { struct vnode * a_dvp; struct vnode ** a_vpp; struct componentname * a_cnp; } */ *ap; { struct vnode **vpp = ap->a_vpp; struct vnode *dvp = ap->a_dvp; struct componentname *cnp = ap->a_cnp; char *pname = cnp->cn_nameptr; struct proc *p = cnp->cn_proc; int nfiles = p->p_fd->fd_nfiles; unsigned fd = -1; int error; struct vnode *fvp; char *ln; if (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME) { error = EROFS; goto bad; } VOP_UNLOCK(dvp, 0, p); if (cnp->cn_namelen == 1 && *pname == '.') { *vpp = dvp; VREF(dvp); vn_lock(dvp, LK_SHARED | LK_RETRY, p); return (0); } switch (VTOFDESC(dvp)->fd_type) { default: case Flink: case Fdesc: case Fctty: error = ENOTDIR; goto bad; case Froot: if (cnp->cn_namelen == 2 && bcmp(pname, "fd", 2) == 0) { error = fdesc_allocvp(Fdevfd, FD_DEVFD, dvp->v_mount, &fvp); if (error) goto bad; *vpp = fvp; fvp->v_type = VDIR; vn_lock(fvp, LK_SHARED | LK_RETRY, p); return (0); } if (cnp->cn_namelen == 3 && bcmp(pname, "tty", 3) == 0) { struct vnode *ttyvp = cttyvp(p); if (ttyvp == NULL) { error = ENXIO; goto bad; } error = fdesc_allocvp(Fctty, FD_CTTY, dvp->v_mount, &fvp); if (error) goto bad; *vpp = fvp; fvp->v_type = VFIFO; vn_lock(fvp, LK_SHARED | LK_RETRY, p); return (0); } ln = 0; switch (cnp->cn_namelen) { case 5: if (bcmp(pname, "stdin", 5) == 0) { ln = "fd/0"; fd = FD_STDIN; } break; case 6: if (bcmp(pname, "stdout", 6) == 0) { ln = "fd/1"; fd = FD_STDOUT; } else if (bcmp(pname, "stderr", 6) == 0) { ln = "fd/2"; fd = FD_STDERR; } break; } if (ln) { error = fdesc_allocvp(Flink, fd, dvp->v_mount, &fvp); if (error) goto bad; VTOFDESC(fvp)->fd_link = ln; *vpp = fvp; fvp->v_type = VLNK; vn_lock(fvp, LK_SHARED | LK_RETRY, p); return (0); } else { error = ENOENT; goto bad; } /* FALL THROUGH */ case Fdevfd: if (cnp->cn_namelen == 2 && bcmp(pname, "..", 2) == 0) { if ((error = fdesc_root(dvp->v_mount, vpp)) != 0) goto bad; return (0); } fd = 0; while (*pname >= '0' && *pname <= '9') { fd = 10 * fd + *pname++ - '0'; if (fd >= nfiles) break; } if (*pname != '\0') { error = ENOENT; goto bad; } if (fd >= nfiles || p->p_fd->fd_ofiles[fd] == NULL) { error = EBADF; goto bad; } error = fdesc_allocvp(Fdesc, FD_DESC+fd, dvp->v_mount, &fvp); if (error) goto bad; VTOFDESC(fvp)->fd_fd = fd; vn_lock(fvp, LK_SHARED | LK_RETRY, p); *vpp = fvp; return (0); } bad:; vn_lock(dvp, LK_SHARED | LK_RETRY, p); *vpp = NULL; return (error); } static int fdesc_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; int error = 0; switch (VTOFDESC(vp)->fd_type) { case Fdesc: /* * XXX Kludge: set p->p_dupfd to contain the value of the * the file descriptor being sought for duplication. The error * return ensures that the vnode for this device will be * released by vn_open. Open will detect this special error and * take the actions in dupfdopen. Other callers of vn_open or * VOP_OPEN will simply report the error. */ ap->a_p->p_dupfd = VTOFDESC(vp)->fd_fd; /* XXX */ error = ENODEV; break; case Fctty: error = (*ctty_cdevsw.d_open)(devctty, ap->a_mode, 0, ap->a_p); break; } return (error); } static int fdesc_attr(fd, vap, cred, p) int fd; struct vattr *vap; struct ucred *cred; struct proc *p; { struct filedesc *fdp = p->p_fd; struct file *fp; struct stat stb; int error; if (fd >= fdp->fd_nfiles || (fp = fdp->fd_ofiles[fd]) == NULL) return (EBADF); switch (fp->f_type) { case DTYPE_FIFO: case DTYPE_VNODE: error = VOP_GETATTR((struct vnode *) fp->f_data, vap, cred, p); if (error == 0 && vap->va_type == VDIR) { /* * directories can cause loops in the namespace, * so turn off the 'x' bits to avoid trouble. */ vap->va_mode &= ~((VEXEC)|(VEXEC>>3)|(VEXEC>>6)); } break; case DTYPE_SOCKET: error = soo_stat((struct socket *)fp->f_data, &stb); if (error == 0) { vattr_null(vap); vap->va_type = VSOCK; vap->va_mode = stb.st_mode; vap->va_nlink = stb.st_nlink; vap->va_uid = stb.st_uid; vap->va_gid = stb.st_gid; vap->va_fsid = stb.st_dev; vap->va_fileid = stb.st_ino; vap->va_size = stb.st_size; vap->va_blocksize = stb.st_blksize; vap->va_atime = stb.st_atimespec; vap->va_mtime = stb.st_mtimespec; vap->va_ctime = stb.st_ctimespec; vap->va_gen = stb.st_gen; vap->va_flags = stb.st_flags; vap->va_rdev = stb.st_rdev; vap->va_bytes = stb.st_blocks * stb.st_blksize; } break; default: panic("fdesc attr"); break; } return (error); } static int fdesc_getattr(ap) struct vop_getattr_args /* { struct vnode *a_vp; struct vattr *a_vap; struct ucred *a_cred; struct proc *a_p; } */ *ap; { struct vnode *vp = ap->a_vp; struct vattr *vap = ap->a_vap; unsigned fd; int error = 0; switch (VTOFDESC(vp)->fd_type) { case Froot: case Fdevfd: case Flink: case Fctty: bzero((caddr_t) vap, sizeof(*vap)); vattr_null(vap); vap->va_fileid = VTOFDESC(vp)->fd_ix; switch (VTOFDESC(vp)->fd_type) { case Flink: vap->va_mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH; vap->va_type = VLNK; vap->va_nlink = 1; vap->va_size = strlen(VTOFDESC(vp)->fd_link); break; case Fctty: vap->va_mode = S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH; vap->va_type = VFIFO; vap->va_nlink = 1; vap->va_size = 0; break; default: vap->va_mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH; vap->va_type = VDIR; vap->va_nlink = 2; vap->va_size = DEV_BSIZE; break; } vap->va_uid = 0; vap->va_gid = 0; vap->va_blocksize = DEV_BSIZE; vap->va_atime.tv_sec = boottime.tv_sec; vap->va_atime.tv_nsec = 0; vap->va_mtime = vap->va_atime; vap->va_ctime = vap->va_mtime; vap->va_gen = 0; vap->va_flags = 0; vap->va_rdev = 0; vap->va_bytes = 0; break; case Fdesc: fd = VTOFDESC(vp)->fd_fd; error = fdesc_attr(fd, vap, ap->a_cred, ap->a_p); break; default: panic("fdesc_getattr"); break; } if (error == 0) vp->v_type = vap->va_type; return (error); } static int fdesc_setattr(ap) struct vop_setattr_args /* { struct vnode *a_vp; struct vattr *a_vap; struct ucred *a_cred; struct proc *a_p; } */ *ap; { struct filedesc *fdp = ap->a_p->p_fd; struct vattr *vap = ap->a_vap; struct file *fp; unsigned fd; int error; /* * Can't mess with the root vnode */ switch (VTOFDESC(ap->a_vp)->fd_type) { case Fdesc: break; case Fctty: if (vap->va_flags != VNOVAL) return (EOPNOTSUPP); return (0); default: return (EACCES); } fd = VTOFDESC(ap->a_vp)->fd_fd; if (fd >= fdp->fd_nfiles || (fp = fdp->fd_ofiles[fd]) == NULL) { return (EBADF); } /* * Can setattr the underlying vnode, but not sockets! */ switch (fp->f_type) { case DTYPE_FIFO: case DTYPE_PIPE: case DTYPE_VNODE: error = VOP_SETATTR((struct vnode *) fp->f_data, ap->a_vap, ap->a_cred, ap->a_p); break; case DTYPE_SOCKET: if (vap->va_flags != VNOVAL) error = EOPNOTSUPP; else error = 0; break; default: error = EBADF; break; } return (error); } #define UIO_MX 16 static struct dirtmp { u_long d_fileno; u_short d_reclen; u_short d_namlen; char d_name[8]; } rootent[] = { { FD_DEVFD, UIO_MX, 2, "fd" }, { FD_STDIN, UIO_MX, 5, "stdin" }, { FD_STDOUT, UIO_MX, 6, "stdout" }, { FD_STDERR, UIO_MX, 6, "stderr" }, { FD_CTTY, UIO_MX, 3, "tty" }, }; static int fdesc_readdir(ap) struct vop_readdir_args /* { struct vnode *a_vp; struct uio *a_uio; struct ucred *a_cred; int *a_eofflag; u_long *a_cookies; int a_ncookies; } */ *ap; { struct uio *uio = ap->a_uio; struct filedesc *fdp; int error, i, off; /* * We don't allow exporting fdesc mounts, and currently local * requests do not need cookies. */ if (ap->a_ncookies) panic("fdesc_readdir: not hungry"); if (VTOFDESC(ap->a_vp)->fd_type != Froot && VTOFDESC(ap->a_vp)->fd_type != Fdevfd) panic("fdesc_readdir: not dir"); off = (int)uio->uio_offset; if (off != uio->uio_offset || off < 0 || (u_int)off % UIO_MX != 0 || uio->uio_resid < UIO_MX) return (EINVAL); i = (u_int)off / UIO_MX; fdp = uio->uio_procp->p_fd; if (VTOFDESC(ap->a_vp)->fd_type == Froot) { struct dirent d; struct dirent *dp = &d; struct dirtmp *dt; error = 0; while (i < sizeof(rootent) / sizeof(rootent[0]) && uio->uio_resid >= UIO_MX) { dt = &rootent[i]; switch (dt->d_fileno) { case FD_CTTY: if (cttyvp(uio->uio_procp) == NULL) continue; break; case FD_STDIN: case FD_STDOUT: case FD_STDERR: if ((dt->d_fileno-FD_STDIN) >= fdp->fd_nfiles) continue; if (fdp->fd_ofiles[dt->d_fileno-FD_STDIN] == NULL) continue; break; } bzero((caddr_t) dp, UIO_MX); dp->d_fileno = dt->d_fileno; dp->d_namlen = dt->d_namlen; dp->d_type = DT_UNKNOWN; dp->d_reclen = dt->d_reclen; bcopy(dt->d_name, dp->d_name, dp->d_namlen+1); error = uiomove((caddr_t) dp, UIO_MX, uio); if (error) break; i++; } uio->uio_offset = i * UIO_MX; return (error); } error = 0; while (i < fdp->fd_nfiles && uio->uio_resid >= UIO_MX) { if (fdp->fd_ofiles[i] != NULL) { struct dirent d; struct dirent *dp = &d; bzero((caddr_t) dp, UIO_MX); dp->d_namlen = sprintf(dp->d_name, "%d", i); dp->d_reclen = UIO_MX; dp->d_type = DT_UNKNOWN; dp->d_fileno = i + FD_STDIN; /* * And ship to userland */ error = uiomove((caddr_t) dp, UIO_MX, uio); if (error) break; } i++; } uio->uio_offset = i * UIO_MX; return (error); } static int fdesc_readlink(ap) struct vop_readlink_args /* { struct vnode *a_vp; struct uio *a_uio; struct ucred *a_cred; } */ *ap; { struct vnode *vp = ap->a_vp; int error; if (vp->v_type != VLNK) return (EPERM); if (VTOFDESC(vp)->fd_type == Flink) { char *ln = VTOFDESC(vp)->fd_link; error = uiomove(ln, strlen(ln), ap->a_uio); } else { error = EOPNOTSUPP; } return (error); } static int fdesc_read(ap) struct vop_read_args /* { struct vnode *a_vp; struct uio *a_uio; int a_ioflag; struct ucred *a_cred; } */ *ap; { int error = EOPNOTSUPP; switch (VTOFDESC(ap->a_vp)->fd_type) { case Fctty: error = (*ctty_cdevsw.d_read)(devctty, ap->a_uio, ap->a_ioflag); break; default: error = EOPNOTSUPP; break; } return (error); } static int fdesc_write(ap) struct vop_write_args /* { struct vnode *a_vp; struct uio *a_uio; int a_ioflag; struct ucred *a_cred; } */ *ap; { int error = EOPNOTSUPP; switch (VTOFDESC(ap->a_vp)->fd_type) { case Fctty: error = (*ctty_cdevsw.d_write)(devctty, ap->a_uio, ap->a_ioflag); break; default: error = EOPNOTSUPP; break; } return (error); } static int fdesc_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; { int error = EOPNOTSUPP; switch (VTOFDESC(ap->a_vp)->fd_type) { case Fctty: error = (*ctty_cdevsw.d_ioctl)(devctty, ap->a_command, ap->a_data, ap->a_fflag, ap->a_p); break; default: error = EOPNOTSUPP; break; } return (error); } static int fdesc_poll(ap) struct vop_poll_args /* { struct vnode *a_vp; int a_events; struct ucred *a_cred; struct proc *a_p; } */ *ap; { int revents; switch (VTOFDESC(ap->a_vp)->fd_type) { case Fctty: revents = (*ctty_cdevsw.d_poll)(devctty, ap->a_events, ap->a_p); break; default: revents = seltrue(0, ap->a_events, ap->a_p); break; } return (revents); } static int fdesc_inactive(ap) struct vop_inactive_args /* { struct vnode *a_vp; struct proc *a_p; } */ *ap; { struct vnode *vp = ap->a_vp; /* * Clear out the v_type field to avoid * nasty things happening in vgone(). */ VOP_UNLOCK(vp, 0, ap->a_p); vp->v_type = VNON; return (0); } static int fdesc_reclaim(ap) struct vop_reclaim_args /* { struct vnode *a_vp; } */ *ap; { struct vnode *vp = ap->a_vp; struct fdescnode *fd = VTOFDESC(vp); LIST_REMOVE(fd, fd_hash); FREE(vp->v_data, M_TEMP); vp->v_data = 0; return (0); } /* * Print out the contents of a /dev/fd vnode. */ /* ARGSUSED */ static int fdesc_print(ap) struct vop_print_args /* { struct vnode *a_vp; } */ *ap; { printf("tag VT_NON, fdesc vnode\n"); return (0); } /* * /dev/fd "should never get here" operation */ static int fdesc_badop() { panic("fdesc: bad op"); /* NOTREACHED */ } static struct vnodeopv_entry_desc fdesc_vnodeop_entries[] = { { &vop_default_desc, (vop_t *) vop_defaultop }, { &vop_access_desc, (vop_t *) vop_null }, { &vop_bmap_desc, (vop_t *) fdesc_badop }, { &vop_getattr_desc, (vop_t *) fdesc_getattr }, { &vop_inactive_desc, (vop_t *) fdesc_inactive }, { &vop_ioctl_desc, (vop_t *) fdesc_ioctl }, { &vop_lookup_desc, (vop_t *) fdesc_lookup }, { &vop_open_desc, (vop_t *) fdesc_open }, { &vop_pathconf_desc, (vop_t *) vop_stdpathconf }, { &vop_poll_desc, (vop_t *) fdesc_poll }, { &vop_print_desc, (vop_t *) fdesc_print }, { &vop_read_desc, (vop_t *) fdesc_read }, { &vop_readdir_desc, (vop_t *) fdesc_readdir }, { &vop_readlink_desc, (vop_t *) fdesc_readlink }, { &vop_reclaim_desc, (vop_t *) fdesc_reclaim }, { &vop_setattr_desc, (vop_t *) fdesc_setattr }, { &vop_write_desc, (vop_t *) fdesc_write }, { NULL, NULL } }; static struct vnodeopv_desc fdesc_vnodeop_opv_desc = { &fdesc_vnodeop_p, fdesc_vnodeop_entries }; VNODEOP_SET(fdesc_vnodeop_opv_desc);