diff options
author | rgrimes <rgrimes@FreeBSD.org> | 1994-05-24 10:09:53 +0000 |
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committer | rgrimes <rgrimes@FreeBSD.org> | 1994-05-24 10:09:53 +0000 |
commit | 27464aaa8e6ad0a90df705f3dd8ea4c48ffefd04 (patch) | |
tree | 498662170037963c8b911613f2622e38efea4434 /sys/fs/specfs | |
parent | 41dbbe7dea1bb3e50798efb3ea01e967bf27364a (diff) | |
download | FreeBSD-src-27464aaa8e6ad0a90df705f3dd8ea4c48ffefd04.zip FreeBSD-src-27464aaa8e6ad0a90df705f3dd8ea4c48ffefd04.tar.gz |
BSD 4.4 Lite Kernel Sources
Diffstat (limited to 'sys/fs/specfs')
-rw-r--r-- | sys/fs/specfs/spec_vnops.c | 689 |
1 files changed, 689 insertions, 0 deletions
diff --git a/sys/fs/specfs/spec_vnops.c b/sys/fs/specfs/spec_vnops.c new file mode 100644 index 0000000..111c517 --- /dev/null +++ b/sys/fs/specfs/spec_vnops.c @@ -0,0 +1,689 @@ +/* + * Copyright (c) 1989, 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. + * + * @(#)spec_vnops.c 8.6 (Berkeley) 4/9/94 + */ + +#include <sys/param.h> +#include <sys/proc.h> +#include <sys/systm.h> +#include <sys/kernel.h> +#include <sys/conf.h> +#include <sys/buf.h> +#include <sys/mount.h> +#include <sys/namei.h> +#include <sys/vnode.h> +#include <sys/stat.h> +#include <sys/errno.h> +#include <sys/ioctl.h> +#include <sys/file.h> +#include <sys/disklabel.h> +#include <miscfs/specfs/specdev.h> + +/* symbolic sleep message strings for devices */ +char devopn[] = "devopn"; +char devio[] = "devio"; +char devwait[] = "devwait"; +char devin[] = "devin"; +char devout[] = "devout"; +char devioc[] = "devioc"; +char devcls[] = "devcls"; + +int (**spec_vnodeop_p)(); +struct vnodeopv_entry_desc spec_vnodeop_entries[] = { + { &vop_default_desc, vn_default_error }, + { &vop_lookup_desc, spec_lookup }, /* lookup */ + { &vop_create_desc, spec_create }, /* create */ + { &vop_mknod_desc, spec_mknod }, /* mknod */ + { &vop_open_desc, spec_open }, /* open */ + { &vop_close_desc, spec_close }, /* close */ + { &vop_access_desc, spec_access }, /* access */ + { &vop_getattr_desc, spec_getattr }, /* getattr */ + { &vop_setattr_desc, spec_setattr }, /* setattr */ + { &vop_read_desc, spec_read }, /* read */ + { &vop_write_desc, spec_write }, /* write */ + { &vop_ioctl_desc, spec_ioctl }, /* ioctl */ + { &vop_select_desc, spec_select }, /* select */ + { &vop_mmap_desc, spec_mmap }, /* mmap */ + { &vop_fsync_desc, spec_fsync }, /* fsync */ + { &vop_seek_desc, spec_seek }, /* seek */ + { &vop_remove_desc, spec_remove }, /* remove */ + { &vop_link_desc, spec_link }, /* link */ + { &vop_rename_desc, spec_rename }, /* rename */ + { &vop_mkdir_desc, spec_mkdir }, /* mkdir */ + { &vop_rmdir_desc, spec_rmdir }, /* rmdir */ + { &vop_symlink_desc, spec_symlink }, /* symlink */ + { &vop_readdir_desc, spec_readdir }, /* readdir */ + { &vop_readlink_desc, spec_readlink }, /* readlink */ + { &vop_abortop_desc, spec_abortop }, /* abortop */ + { &vop_inactive_desc, spec_inactive }, /* inactive */ + { &vop_reclaim_desc, spec_reclaim }, /* reclaim */ + { &vop_lock_desc, spec_lock }, /* lock */ + { &vop_unlock_desc, spec_unlock }, /* unlock */ + { &vop_bmap_desc, spec_bmap }, /* bmap */ + { &vop_strategy_desc, spec_strategy }, /* strategy */ + { &vop_print_desc, spec_print }, /* print */ + { &vop_islocked_desc, spec_islocked }, /* islocked */ + { &vop_pathconf_desc, spec_pathconf }, /* pathconf */ + { &vop_advlock_desc, spec_advlock }, /* advlock */ + { &vop_blkatoff_desc, spec_blkatoff }, /* blkatoff */ + { &vop_valloc_desc, spec_valloc }, /* valloc */ + { &vop_vfree_desc, spec_vfree }, /* vfree */ + { &vop_truncate_desc, spec_truncate }, /* truncate */ + { &vop_update_desc, spec_update }, /* update */ + { &vop_bwrite_desc, spec_bwrite }, /* bwrite */ + { (struct vnodeop_desc*)NULL, (int(*)())NULL } +}; +struct vnodeopv_desc spec_vnodeop_opv_desc = + { &spec_vnodeop_p, spec_vnodeop_entries }; + +/* + * Trivial lookup routine that always fails. + */ +int +spec_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 a special file. + */ +/* ARGSUSED */ +spec_open(ap) + struct vop_open_args /* { + struct vnode *a_vp; + int a_mode; + struct ucred *a_cred; + struct proc *a_p; + } */ *ap; +{ + struct vnode *bvp, *vp = ap->a_vp; + dev_t bdev, dev = (dev_t)vp->v_rdev; + register int maj = major(dev); + int error; + + /* + * Don't allow open if fs is mounted -nodev. + */ + if (vp->v_mount && (vp->v_mount->mnt_flag & MNT_NODEV)) + return (ENXIO); + + switch (vp->v_type) { + + case VCHR: + if ((u_int)maj >= nchrdev) + return (ENXIO); + if (ap->a_cred != FSCRED && (ap->a_mode & FWRITE)) { + /* + * When running in very secure mode, do not allow + * opens for writing of any disk character devices. + */ + if (securelevel >= 2 && isdisk(dev, VCHR)) + return (EPERM); + /* + * When running in secure mode, do not allow opens + * for writing of /dev/mem, /dev/kmem, or character + * devices whose corresponding block devices are + * currently mounted. + */ + if (securelevel >= 1) { + if ((bdev = chrtoblk(dev)) != NODEV && + vfinddev(bdev, VBLK, &bvp) && + bvp->v_usecount > 0 && + (error = vfs_mountedon(bvp))) + return (error); + if (iskmemdev(dev)) + return (EPERM); + } + } + VOP_UNLOCK(vp); + error = (*cdevsw[maj].d_open)(dev, ap->a_mode, S_IFCHR, ap->a_p); + VOP_LOCK(vp); + return (error); + + case VBLK: + if ((u_int)maj >= nblkdev) + return (ENXIO); + /* + * When running in very secure mode, do not allow + * opens for writing of any disk block devices. + */ + if (securelevel >= 2 && ap->a_cred != FSCRED && + (ap->a_mode & FWRITE) && isdisk(dev, VBLK)) + return (EPERM); + /* + * Do not allow opens of block devices that are + * currently mounted. + */ + if (error = vfs_mountedon(vp)) + return (error); + return ((*bdevsw[maj].d_open)(dev, ap->a_mode, S_IFBLK, ap->a_p)); + } + return (0); +} + +/* + * Vnode op for read + */ +/* ARGSUSED */ +spec_read(ap) + struct vop_read_args /* { + struct vnode *a_vp; + struct uio *a_uio; + int a_ioflag; + struct ucred *a_cred; + } */ *ap; +{ + register struct vnode *vp = ap->a_vp; + register struct uio *uio = ap->a_uio; + struct proc *p = uio->uio_procp; + struct buf *bp; + daddr_t bn, nextbn; + long bsize, bscale; + struct partinfo dpart; + int n, on, majordev, (*ioctl)(); + int error = 0; + dev_t dev; + +#ifdef DIAGNOSTIC + if (uio->uio_rw != UIO_READ) + panic("spec_read mode"); + if (uio->uio_segflg == UIO_USERSPACE && uio->uio_procp != curproc) + panic("spec_read proc"); +#endif + if (uio->uio_resid == 0) + return (0); + + switch (vp->v_type) { + + case VCHR: + VOP_UNLOCK(vp); + error = (*cdevsw[major(vp->v_rdev)].d_read) + (vp->v_rdev, uio, ap->a_ioflag); + VOP_LOCK(vp); + return (error); + + case VBLK: + if (uio->uio_offset < 0) + return (EINVAL); + bsize = BLKDEV_IOSIZE; + dev = vp->v_rdev; + if ((majordev = major(dev)) < nblkdev && + (ioctl = bdevsw[majordev].d_ioctl) != NULL && + (*ioctl)(dev, DIOCGPART, (caddr_t)&dpart, FREAD, p) == 0 && + dpart.part->p_fstype == FS_BSDFFS && + dpart.part->p_frag != 0 && dpart.part->p_fsize != 0) + bsize = dpart.part->p_frag * dpart.part->p_fsize; + bscale = bsize / DEV_BSIZE; + do { + bn = (uio->uio_offset / DEV_BSIZE) &~ (bscale - 1); + on = uio->uio_offset % bsize; + n = min((unsigned)(bsize - on), uio->uio_resid); + if (vp->v_lastr + bscale == bn) { + nextbn = bn + bscale; + error = breadn(vp, bn, (int)bsize, &nextbn, + (int *)&bsize, 1, NOCRED, &bp); + } else + error = bread(vp, bn, (int)bsize, NOCRED, &bp); + vp->v_lastr = bn; + n = min(n, bsize - bp->b_resid); + if (error) { + brelse(bp); + return (error); + } + error = uiomove((char *)bp->b_data + on, n, uio); + if (n + on == bsize) + bp->b_flags |= B_AGE; + brelse(bp); + } while (error == 0 && uio->uio_resid > 0 && n != 0); + return (error); + + default: + panic("spec_read type"); + } + /* NOTREACHED */ +} + +/* + * Vnode op for write + */ +/* ARGSUSED */ +spec_write(ap) + struct vop_write_args /* { + struct vnode *a_vp; + struct uio *a_uio; + int a_ioflag; + struct ucred *a_cred; + } */ *ap; +{ + register struct vnode *vp = ap->a_vp; + register struct uio *uio = ap->a_uio; + struct proc *p = uio->uio_procp; + struct buf *bp; + daddr_t bn; + int bsize, blkmask; + struct partinfo dpart; + register int n, on; + int error = 0; + +#ifdef DIAGNOSTIC + if (uio->uio_rw != UIO_WRITE) + panic("spec_write mode"); + if (uio->uio_segflg == UIO_USERSPACE && uio->uio_procp != curproc) + panic("spec_write proc"); +#endif + + switch (vp->v_type) { + + case VCHR: + VOP_UNLOCK(vp); + error = (*cdevsw[major(vp->v_rdev)].d_write) + (vp->v_rdev, uio, ap->a_ioflag); + VOP_LOCK(vp); + return (error); + + case VBLK: + if (uio->uio_resid == 0) + return (0); + if (uio->uio_offset < 0) + return (EINVAL); + bsize = BLKDEV_IOSIZE; + if ((*bdevsw[major(vp->v_rdev)].d_ioctl)(vp->v_rdev, DIOCGPART, + (caddr_t)&dpart, FREAD, p) == 0) { + if (dpart.part->p_fstype == FS_BSDFFS && + dpart.part->p_frag != 0 && dpart.part->p_fsize != 0) + bsize = dpart.part->p_frag * + dpart.part->p_fsize; + } + blkmask = (bsize / DEV_BSIZE) - 1; + do { + bn = (uio->uio_offset / DEV_BSIZE) &~ blkmask; + on = uio->uio_offset % bsize; + n = min((unsigned)(bsize - on), uio->uio_resid); + if (n == bsize) + bp = getblk(vp, bn, bsize, 0, 0); + else + error = bread(vp, bn, bsize, NOCRED, &bp); + n = min(n, bsize - bp->b_resid); + if (error) { + brelse(bp); + return (error); + } + error = uiomove((char *)bp->b_data + on, n, uio); + if (n + on == bsize) { + bp->b_flags |= B_AGE; + bawrite(bp); + } else + bdwrite(bp); + } while (error == 0 && uio->uio_resid > 0 && n != 0); + return (error); + + default: + panic("spec_write type"); + } + /* NOTREACHED */ +} + +/* + * Device ioctl operation. + */ +/* ARGSUSED */ +spec_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; +{ + dev_t dev = ap->a_vp->v_rdev; + + switch (ap->a_vp->v_type) { + + case VCHR: + return ((*cdevsw[major(dev)].d_ioctl)(dev, ap->a_command, ap->a_data, + ap->a_fflag, ap->a_p)); + + case VBLK: + if (ap->a_command == 0 && (int)ap->a_data == B_TAPE) + if (bdevsw[major(dev)].d_flags & B_TAPE) + return (0); + else + return (1); + return ((*bdevsw[major(dev)].d_ioctl)(dev, ap->a_command, ap->a_data, + ap->a_fflag, ap->a_p)); + + default: + panic("spec_ioctl"); + /* NOTREACHED */ + } +} + +/* ARGSUSED */ +spec_select(ap) + struct vop_select_args /* { + struct vnode *a_vp; + int a_which; + int a_fflags; + struct ucred *a_cred; + struct proc *a_p; + } */ *ap; +{ + register dev_t dev; + + switch (ap->a_vp->v_type) { + + default: + return (1); /* XXX */ + + case VCHR: + dev = ap->a_vp->v_rdev; + return (*cdevsw[major(dev)].d_select)(dev, ap->a_which, ap->a_p); + } +} +/* + * Synch buffers associated with a block device + */ +/* ARGSUSED */ +int +spec_fsync(ap) + struct vop_fsync_args /* { + struct vnode *a_vp; + struct ucred *a_cred; + int a_waitfor; + struct proc *a_p; + } */ *ap; +{ + register struct vnode *vp = ap->a_vp; + register struct buf *bp; + struct buf *nbp; + int s; + + if (vp->v_type == VCHR) + return (0); + /* + * Flush all dirty buffers associated with a block device. + */ +loop: + s = splbio(); + for (bp = vp->v_dirtyblkhd.lh_first; bp; bp = nbp) { + nbp = bp->b_vnbufs.le_next; + if ((bp->b_flags & B_BUSY)) + continue; + if ((bp->b_flags & B_DELWRI) == 0) + panic("spec_fsync: not dirty"); + bremfree(bp); + bp->b_flags |= B_BUSY; + splx(s); + bawrite(bp); + goto loop; + } + if (ap->a_waitfor == MNT_WAIT) { + while (vp->v_numoutput) { + vp->v_flag |= VBWAIT; + sleep((caddr_t)&vp->v_numoutput, PRIBIO + 1); + } +#ifdef DIAGNOSTIC + if (vp->v_dirtyblkhd.lh_first) { + vprint("spec_fsync: dirty", vp); + goto loop; + } +#endif + } + splx(s); + return (0); +} + +/* + * Just call the device strategy routine + */ +spec_strategy(ap) + struct vop_strategy_args /* { + struct buf *a_bp; + } */ *ap; +{ + + (*bdevsw[major(ap->a_bp->b_dev)].d_strategy)(ap->a_bp); + return (0); +} + +/* + * This is a noop, simply returning what one has been given. + */ +spec_bmap(ap) + struct vop_bmap_args /* { + struct vnode *a_vp; + daddr_t a_bn; + struct vnode **a_vpp; + daddr_t *a_bnp; + } */ *ap; +{ + + 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 */ +spec_lock(ap) + struct vop_lock_args /* { + struct vnode *a_vp; + } */ *ap; +{ + + return (0); +} + +/* ARGSUSED */ +spec_unlock(ap) + struct vop_unlock_args /* { + struct vnode *a_vp; + } */ *ap; +{ + + return (0); +} + +/* + * Device close routine + */ +/* ARGSUSED */ +spec_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; + dev_t dev = vp->v_rdev; + int (*devclose) __P((dev_t, int, int, struct proc *)); + int mode, error; + + switch (vp->v_type) { + + case VCHR: + /* + * Hack: a tty device that is a controlling terminal + * has a reference from the session structure. + * We cannot easily tell that a character device is + * a controlling terminal, unless it is the closing + * process' controlling terminal. In that case, + * if the reference count is 2 (this last descriptor + * plus the session), release the reference from the session. + */ + if (vcount(vp) == 2 && ap->a_p && + vp == ap->a_p->p_session->s_ttyvp) { + vrele(vp); + ap->a_p->p_session->s_ttyvp = NULL; + } + /* + * If the vnode is locked, then we are in the midst + * of forcably closing the device, otherwise we only + * close on last reference. + */ + if (vcount(vp) > 1 && (vp->v_flag & VXLOCK) == 0) + return (0); + devclose = cdevsw[major(dev)].d_close; + mode = S_IFCHR; + break; + + case VBLK: + /* + * On last close of a block device (that isn't mounted) + * we must invalidate any in core blocks, so that + * we can, for instance, change floppy disks. + */ + if (error = vinvalbuf(vp, V_SAVE, ap->a_cred, ap->a_p, 0, 0)) + return (error); + /* + * We do not want to really close the device if it + * is still in use unless we are trying to close it + * forcibly. Since every use (buffer, vnode, swap, cmap) + * holds a reference to the vnode, and because we mark + * any other vnodes that alias this device, when the + * sum of the reference counts on all the aliased + * vnodes descends to one, we are on last close. + */ + if (vcount(vp) > 1 && (vp->v_flag & VXLOCK) == 0) + return (0); + devclose = bdevsw[major(dev)].d_close; + mode = S_IFBLK; + break; + + default: + panic("spec_close: not special"); + } + + return ((*devclose)(dev, ap->a_fflag, mode, ap->a_p)); +} + +/* + * Print out the contents of a special device vnode. + */ +spec_print(ap) + struct vop_print_args /* { + struct vnode *a_vp; + } */ *ap; +{ + + printf("tag VT_NON, dev %d, %d\n", major(ap->a_vp->v_rdev), + minor(ap->a_vp->v_rdev)); +} + +/* + * Return POSIX pathconf information applicable to special devices. + */ +spec_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_MAX_CANON: + *ap->a_retval = MAX_CANON; + return (0); + case _PC_MAX_INPUT: + *ap->a_retval = MAX_INPUT; + return (0); + case _PC_PIPE_BUF: + *ap->a_retval = PIPE_BUF; + return (0); + case _PC_CHOWN_RESTRICTED: + *ap->a_retval = 1; + return (0); + case _PC_VDISABLE: + *ap->a_retval = _POSIX_VDISABLE; + return (0); + default: + return (EINVAL); + } + /* NOTREACHED */ +} + +/* + * Special device advisory byte-level locks. + */ +/* ARGSUSED */ +spec_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 (EOPNOTSUPP); +} + +/* + * Special device failed operation + */ +spec_ebadf() +{ + + return (EBADF); +} + +/* + * Special device bad operation + */ +spec_badop() +{ + + panic("spec_badop called"); + /* NOTREACHED */ +} |