initial import of NetBSD tree

1 files changed, 596 insertions, 0 deletions

diff --git a/sys/dev/vnd.c b/sys/dev/vnd.c
new file mode 100644
index 00000000000..1c8e5109bbb
--- /dev/null
+++ b/sys/dev/vnd.c
@@ -0,0 +1,596 @@
+/*	$NetBSD: vnd.c,v 1.21 1995/10/05 06:20:57 mycroft Exp $	*/
+
+/*
+ * Copyright (c) 1988 University of Utah.
+ * Copyright (c) 1990, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * the Systems Programming Group of the University of Utah Computer
+ * Science Department.
+ *
+ * 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.
+ *
+ * from: Utah $Hdr: vn.c 1.13 94/04/02$
+ *
+ *	@(#)vn.c	8.6 (Berkeley) 4/1/94
+ */
+
+/*
+ * Vnode disk driver.
+ *
+ * Block/character interface to a vnode.  Allows one to treat a file
+ * as a disk (e.g. build a filesystem in it, mount it, etc.).
+ *
+ * NOTE 1: This uses the VOP_BMAP/VOP_STRATEGY interface to the vnode
+ * instead of a simple VOP_RDWR.  We do this to avoid distorting the
+ * local buffer cache.
+ *
+ * NOTE 2: There is a security issue involved with this driver.
+ * Once mounted all access to the contents of the "mapped" file via
+ * the special file is controlled by the permissions on the special
+ * file, the protection of the mapped file is ignored (effectively,
+ * by using root credentials in all transactions).
+ *
+ * NOTE 3: Doesn't interact with leases, should it?
+ */
+#include "vnd.h"
+#if NVND > 0
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/namei.h>
+#include <sys/proc.h>
+#include <sys/errno.h>
+#include <sys/dkstat.h>
+#include <sys/buf.h>
+#include <sys/malloc.h>
+#include <sys/ioctl.h>
+#include <sys/disklabel.h>
+#include <sys/mount.h>
+#include <sys/vnode.h>
+#include <sys/file.h>
+#include <sys/uio.h>
+
+#include <miscfs/specfs/specdev.h>
+
+#include <dev/vndioctl.h>
+
+#ifdef DEBUG
+int dovndcluster = 1;
+int vnddebug = 0x00;
+#define VDB_FOLLOW	0x01
+#define VDB_INIT	0x02
+#define VDB_IO		0x04
+#endif
+
+#define b_cylin	b_resid
+
+#define	vndunit(x)	DISKUNIT(x)
+
+struct vndbuf {
+	struct buf	vb_buf;
+	struct buf	*vb_obp;
+};
+
+#define	getvndbuf()	\
+	((struct vndbuf *)malloc(sizeof(struct vndbuf), M_DEVBUF, M_WAITOK))
+#define putvndbuf(vbp)	\
+	free((caddr_t)(vbp), M_DEVBUF)
+
+struct vnd_softc {
+	int		 sc_flags;	/* flags */
+	size_t		 sc_size;	/* size of vnd */
+	struct vnode	*sc_vp;		/* vnode */
+	struct ucred	*sc_cred;	/* credentials */
+	int		 sc_maxactive;	/* max # of active requests */
+	struct buf	 sc_tab;	/* transfer queue */
+};
+
+/* sc_flags */
+#define	VNF_ALIVE	0x01
+#define VNF_INITED	0x02
+
+#if 0	/* if you need static allocation */
+struct vnd_softc vn_softc[NVND];
+int numvnd = NVND;
+#else
+struct vnd_softc *vnd_softc;
+int numvnd;
+#endif
+
+void	vndclear __P((struct vnd_softc *));
+void	vndstart __P((struct vnd_softc *));
+int	vndsetcred __P((struct vnd_softc *, struct ucred *));
+void	vndthrottle __P((struct vnd_softc *, struct vnode *));
+
+void
+vndattach(num)
+	int num;
+{
+	char *mem;
+	register u_long size;
+
+	if (num <= 0)
+		return;
+	size = num * sizeof(struct vnd_softc);
+	mem = malloc(size, M_DEVBUF, M_NOWAIT);
+	if (mem == NULL) {
+		printf("WARNING: no memory for vnode disks\n");
+		return;
+	}
+	bzero(mem, size);
+	vnd_softc = (struct vnd_softc *)mem;
+	numvnd = num;
+}
+
+int
+vndopen(dev, flags, mode, p)
+	dev_t dev;
+	int flags, mode;
+	struct proc *p;
+{
+	int unit = vndunit(dev);
+
+#ifdef DEBUG
+	if (vnddebug & VDB_FOLLOW)
+		printf("vndopen(%x, %x, %x, %x)\n", dev, flags, mode, p);
+#endif
+	if (unit >= numvnd)
+		return(ENXIO);
+	return(0);
+}
+
+int
+vndclose(dev, flags, mode, p)
+	dev_t dev;
+	int flags, mode;
+	struct proc *p;
+{
+#ifdef DEBUG
+	if (vnddebug & VDB_FOLLOW)
+		printf("vndclose(%x, %x, %x, %x)\n", dev, flags, mode, p);
+#endif
+	return 0;
+}
+
+/*
+ * Break the request into bsize pieces and submit using VOP_BMAP/VOP_STRATEGY.
+ * Note that this driver can only be used for swapping over NFS on the hp
+ * since nfs_strategy on the vax cannot handle u-areas and page tables.
+ */
+void
+vndstrategy(bp)
+	register struct buf *bp;
+{
+	int unit = vndunit(bp->b_dev);
+	register struct vnd_softc *vnd = &vnd_softc[unit];
+	register struct vndbuf *nbp;
+	register int bn, bsize, resid;
+	register caddr_t addr;
+	int sz, flags, error;
+	extern void vndiodone();
+
+#ifdef DEBUG
+	if (vnddebug & VDB_FOLLOW)
+		printf("vndstrategy(%x): unit %d\n", bp, unit);
+#endif
+	if ((vnd->sc_flags & VNF_INITED) == 0) {
+		bp->b_error = ENXIO;
+		bp->b_flags |= B_ERROR;
+		biodone(bp);
+		return;
+	}
+	bn = bp->b_blkno;
+	sz = howmany(bp->b_bcount, DEV_BSIZE);
+	bp->b_resid = bp->b_bcount;
+	if (bn < 0 || bn + sz > vnd->sc_size) {
+		if (bn != vnd->sc_size) {
+			bp->b_error = EINVAL;
+			bp->b_flags |= B_ERROR;
+		}
+		biodone(bp);
+		return;
+	}
+	bn = dbtob(bn);
+ 	bsize = vnd->sc_vp->v_mount->mnt_stat.f_iosize;
+	addr = bp->b_data;
+	flags = bp->b_flags | B_CALL;
+	for (resid = bp->b_resid; resid; resid -= sz) {
+		struct vnode *vp;
+		daddr_t nbn;
+		int off, s, nra;
+
+		nra = 0;
+		VOP_LOCK(vnd->sc_vp);
+		error = VOP_BMAP(vnd->sc_vp, bn / bsize, &vp, &nbn, &nra);
+		VOP_UNLOCK(vnd->sc_vp);
+		if (error == 0 && (long)nbn == -1)
+			error = EIO;
+#ifdef DEBUG
+		if (!dovndcluster)
+			nra = 0;
+#endif
+
+		if (off = bn % bsize)
+			sz = bsize - off;
+		else
+			sz = (1 + nra) * bsize;
+		if (resid < sz)
+			sz = resid;
+#ifdef DEBUG
+		if (vnddebug & VDB_IO)
+			printf("vndstrategy: vp %x/%x bn %x/%x sz %x\n",
+			       vnd->sc_vp, vp, bn, nbn, sz);
+#endif
+
+		nbp = getvndbuf();
+		nbp->vb_buf.b_flags = flags;
+		nbp->vb_buf.b_bcount = sz;
+		nbp->vb_buf.b_bufsize = bp->b_bufsize;
+		nbp->vb_buf.b_error = 0;
+		if (vp->v_type == VBLK || vp->v_type == VCHR)
+			nbp->vb_buf.b_dev = vp->v_rdev;
+		else
+			nbp->vb_buf.b_dev = NODEV;
+		nbp->vb_buf.b_data = addr;
+		nbp->vb_buf.b_blkno = nbn + btodb(off);
+		nbp->vb_buf.b_proc = bp->b_proc;
+		nbp->vb_buf.b_iodone = vndiodone;
+		nbp->vb_buf.b_vp = vp;
+		nbp->vb_buf.b_rcred = vnd->sc_cred;	/* XXX crdup? */
+		nbp->vb_buf.b_wcred = vnd->sc_cred;	/* XXX crdup? */
+		nbp->vb_buf.b_dirtyoff = bp->b_dirtyoff;
+		nbp->vb_buf.b_dirtyend = bp->b_dirtyend;
+		nbp->vb_buf.b_validoff = bp->b_validoff;
+		nbp->vb_buf.b_validend = bp->b_validend;
+
+		/* save a reference to the old buffer */
+		nbp->vb_obp = bp;
+
+		/*
+		 * If there was an error or a hole in the file...punt.
+		 * Note that we deal with this after the nbp allocation.
+		 * This ensures that we properly clean up any operations
+		 * that we have already fired off.
+		 *
+		 * XXX we could deal with holes here but it would be
+		 * a hassle (in the write case).
+		 */
+		if (error) {
+			nbp->vb_buf.b_error = error;
+			nbp->vb_buf.b_flags |= B_ERROR;
+			bp->b_resid -= (resid - sz);
+			biodone(&nbp->vb_buf);
+			return;
+		}
+		/*
+		 * Just sort by block number
+		 */
+		nbp->vb_buf.b_cylin = nbp->vb_buf.b_blkno;
+		s = splbio();
+		disksort(&vnd->sc_tab, &nbp->vb_buf);
+		if (vnd->sc_tab.b_active < vnd->sc_maxactive) {
+			vnd->sc_tab.b_active++;
+			vndstart(vnd);
+		}
+		splx(s);
+		bn += sz;
+		addr += sz;
+	}
+}
+
+/*
+ * Feed requests sequentially.
+ * We do it this way to keep from flooding NFS servers if we are connected
+ * to an NFS file.  This places the burden on the client rather than the
+ * server.
+ */
+void
+vndstart(vnd)
+	register struct vnd_softc *vnd;
+{
+	register struct buf *bp;
+
+	/*
+	 * Dequeue now since lower level strategy routine might
+	 * queue using same links
+	 */
+	bp = vnd->sc_tab.b_actf;
+	vnd->sc_tab.b_actf = bp->b_actf;
+#ifdef DEBUG
+	if (vnddebug & VDB_IO)
+		printf("vndstart(%d): bp %x vp %x blkno %x addr %x cnt %x\n",
+		    vnd-vnd_softc, bp, bp->b_vp, bp->b_blkno, bp->b_data,
+		    bp->b_bcount);
+#endif
+	if ((bp->b_flags & B_READ) == 0)
+		bp->b_vp->v_numoutput++;
+	VOP_STRATEGY(bp);
+}
+
+void
+vndiodone(vbp)
+	register struct vndbuf *vbp;
+{
+	register struct buf *pbp = vbp->vb_obp;
+	register struct vnd_softc *vnd = &vnd_softc[vndunit(pbp->b_dev)];
+	int s;
+
+	s = splbio();
+#ifdef DEBUG
+	if (vnddebug & VDB_IO)
+		printf("vndiodone(%d): vbp %x vp %x blkno %x addr %x cnt %x\n",
+		    vnd-vnd_softc, vbp, vbp->vb_buf.b_vp, vbp->vb_buf.b_blkno,
+		    vbp->vb_buf.b_data, vbp->vb_buf.b_bcount);
+#endif
+	if (vbp->vb_buf.b_error) {
+#ifdef DEBUG
+		if (vnddebug & VDB_IO)
+			printf("vndiodone: vbp %x error %d\n", vbp,
+			    vbp->vb_buf.b_error);
+#endif
+		pbp->b_flags |= B_ERROR;
+		pbp->b_error = biowait(&vbp->vb_buf);
+	}
+	pbp->b_resid -= vbp->vb_buf.b_bcount;
+	putvndbuf(vbp);
+	if (pbp->b_resid == 0) {
+#ifdef DEBUG
+		if (vnddebug & VDB_IO)
+			printf("vndiodone: pbp %x iodone\n", pbp);
+#endif
+		biodone(pbp);
+	}
+	if (vnd->sc_tab.b_actf)
+		vndstart(vnd);
+	else
+		vnd->sc_tab.b_active--;
+	splx(s);
+}
+
+int
+vndread(dev, uio)
+	dev_t dev;
+	struct uio *uio;
+{
+
+#ifdef DEBUG
+	if (vnddebug & VDB_FOLLOW)
+		printf("vndread(%x, %x)\n", dev, uio);
+#endif
+	return (physio(vndstrategy, NULL, dev, B_READ, minphys, uio));
+}
+
+int
+vndwrite(dev, uio)
+	dev_t dev;
+	struct uio *uio;
+{
+
+#ifdef DEBUG
+	if (vnddebug & VDB_FOLLOW)
+		printf("vndwrite(%x, %x)\n", dev, uio);
+#endif
+	return (physio(vndstrategy, NULL, dev, B_WRITE, minphys, uio));
+}
+
+/* ARGSUSED */
+int
+vndioctl(dev, cmd, data, flag, p)
+	dev_t dev;
+	u_long cmd;
+	caddr_t data;
+	int flag;
+	struct proc *p;
+{
+	int unit = vndunit(dev);
+	register struct vnd_softc *vnd;
+	struct vnd_ioctl *vio;
+	struct vattr vattr;
+	struct nameidata nd;
+	int error;
+
+#ifdef DEBUG
+	if (vnddebug & VDB_FOLLOW)
+		printf("vndioctl(%x, %lx, %x, %x, %x): unit %d\n",
+		    dev, cmd, data, flag, p, unit);
+#endif
+	error = suser(p->p_ucred, &p->p_acflag);
+	if (error)
+		return (error);
+	if (unit >= numvnd)
+		return (ENXIO);
+
+	vnd = &vnd_softc[unit];
+	vio = (struct vnd_ioctl *)data;
+	switch (cmd) {
+
+	case VNDIOCSET:
+		if (vnd->sc_flags & VNF_INITED)
+			return(EBUSY);
+		/*
+		 * Always open for read and write.
+		 * This is probably bogus, but it lets vn_open()
+		 * weed out directories, sockets, etc. so we don't
+		 * have to worry about them.
+		 */
+		NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, vio->vnd_file, p);
+		if (error = vn_open(&nd, FREAD|FWRITE, 0))
+			return(error);
+		if (error = VOP_GETATTR(nd.ni_vp, &vattr, p->p_ucred, p)) {
+			VOP_UNLOCK(nd.ni_vp);
+			(void) vn_close(nd.ni_vp, FREAD|FWRITE, p->p_ucred, p);
+			return(error);
+		}
+		VOP_UNLOCK(nd.ni_vp);
+		vnd->sc_vp = nd.ni_vp;
+		vnd->sc_size = btodb(vattr.va_size);	/* note truncation */
+		if (error = vndsetcred(vnd, p->p_ucred)) {
+			(void) vn_close(nd.ni_vp, FREAD|FWRITE, p->p_ucred, p);
+			return(error);
+		}
+		vndthrottle(vnd, vnd->sc_vp);
+		vio->vnd_size = dbtob(vnd->sc_size);
+		vnd->sc_flags |= VNF_INITED;
+#ifdef DEBUG
+		if (vnddebug & VDB_INIT)
+			printf("vndioctl: SET vp %x size %x\n",
+			    vnd->sc_vp, vnd->sc_size);
+#endif
+		break;
+
+	case VNDIOCCLR:
+		if ((vnd->sc_flags & VNF_INITED) == 0)
+			return(ENXIO);
+		vndclear(vnd);
+#ifdef DEBUG
+		if (vnddebug & VDB_INIT)
+			printf("vndioctl: CLRed\n");
+#endif
+		break;
+
+	default:
+		return(ENOTTY);
+	}
+	return(0);
+}
+
+/*
+ * Duplicate the current processes' credentials.  Since we are called only
+ * as the result of a SET ioctl and only root can do that, any future access
+ * to this "disk" is essentially as root.  Note that credentials may change
+ * if some other uid can write directly to the mapped file (NFS).
+ */
+int
+vndsetcred(vnd, cred)
+	register struct vnd_softc *vnd;
+	struct ucred *cred;
+{
+	struct uio auio;
+	struct iovec aiov;
+	char *tmpbuf;
+	int error;
+
+	vnd->sc_cred = crdup(cred);
+	tmpbuf = malloc(DEV_BSIZE, M_TEMP, M_WAITOK);
+
+	/* XXX: Horrible kludge to establish credentials for NFS */
+	aiov.iov_base = tmpbuf;
+	aiov.iov_len = min(DEV_BSIZE, dbtob(vnd->sc_size));
+	auio.uio_iov = &aiov;
+	auio.uio_iovcnt = 1;
+	auio.uio_offset = 0;
+	auio.uio_rw = UIO_READ;
+	auio.uio_segflg = UIO_SYSSPACE;
+	auio.uio_resid = aiov.iov_len;
+	VOP_LOCK(vnd->sc_vp);
+	error = VOP_READ(vnd->sc_vp, &auio, 0, vnd->sc_cred);
+	VOP_UNLOCK(vnd->sc_vp);
+
+	free(tmpbuf, M_TEMP);
+	return (error);
+}
+
+/*
+ * Set maxactive based on FS type
+ */
+void
+vndthrottle(vnd, vp)
+	register struct vnd_softc *vnd;
+	struct vnode *vp;
+{
+#ifdef NFSCLIENT
+	extern int (**nfsv2_vnodeop_p)();
+
+	if (vp->v_op == nfsv2_vnodeop_p)
+		vnd->sc_maxactive = 2;
+	else
+#endif
+		vnd->sc_maxactive = 8;
+
+	if (vnd->sc_maxactive < 1)
+		vnd->sc_maxactive = 1;
+}
+
+void
+vndshutdown()
+{
+	register struct vnd_softc *vnd;
+
+	for (vnd = &vnd_softc[0]; vnd < &vnd_softc[numvnd]; vnd++)
+		if (vnd->sc_flags & VNF_INITED)
+			vndclear(vnd);
+}
+
+void
+vndclear(vnd)
+	register struct vnd_softc *vnd;
+{
+	register struct vnode *vp = vnd->sc_vp;
+	struct proc *p = curproc;		/* XXX */
+
+#ifdef DEBUG
+	if (vnddebug & VDB_FOLLOW)
+		printf("vndclear(%x): vp %x\n", vp);
+#endif
+	vnd->sc_flags &= ~VNF_INITED;
+	if (vp == (struct vnode *)0)
+		panic("vndioctl: null vp");
+	(void) vn_close(vp, FREAD|FWRITE, vnd->sc_cred, p);
+	crfree(vnd->sc_cred);
+	vnd->sc_vp = (struct vnode *)0;
+	vnd->sc_cred = (struct ucred *)0;
+	vnd->sc_size = 0;
+}
+
+int
+vndsize(dev)
+	dev_t dev;
+{
+	int unit = vndunit(dev);
+	register struct vnd_softc *vnd = &vnd_softc[unit];
+
+	if (unit >= numvnd || (vnd->sc_flags & VNF_INITED) == 0)
+		return(-1);
+	return(vnd->sc_size);
+}
+
+int
+vnddump(dev, blkno, va, size)
+	dev_t dev;
+	daddr_t blkno;
+	caddr_t va;
+	size_t size;
+{
+
+	/* Not implemented. */
+	return ENXIO;
+}
+#endif