1 files changed, 624 insertions, 0 deletions

diff --git a/sys/kern/vfs_vnops.c b/sys/kern/vfs_vnops.c
new file mode 100644
index 0000000..ebe3497
--- /dev/null
+++ b/sys/kern/vfs_vnops.c
@@ -0,0 +1,624 @@
+/*
+ * Copyright (c) 1982, 1986, 1989, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ * (c) UNIX System Laboratories, Inc.
+ * All or some portions of this file are derived from material licensed
+ * to the University of California by American Telephone and Telegraph
+ * Co. or Unix System Laboratories, Inc. and are reproduced herein with
+ * the permission of UNIX System Laboratories, Inc.
+ *
+ * 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.
+ *
+ *	@(#)vfs_vnops.c	8.2 (Berkeley) 1/21/94
+ * $FreeBSD$
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/fcntl.h>
+#include <sys/file.h>
+#include <sys/stat.h>
+#include <sys/proc.h>
+#include <sys/mount.h>
+#include <sys/namei.h>
+#include <sys/vnode.h>
+#include <sys/buf.h>
+#include <sys/filio.h>
+#include <sys/ttycom.h>
+#include <sys/conf.h>
+
+static int vn_closefile __P((struct file *fp, struct proc *p));
+static int vn_ioctl __P((struct file *fp, u_long com, caddr_t data, 
+		struct proc *p));
+static int vn_read __P((struct file *fp, struct uio *uio, 
+		struct ucred *cred, int flags, struct proc *p));
+static int vn_poll __P((struct file *fp, int events, struct ucred *cred,
+		struct proc *p));
+static int vn_statfile __P((struct file *fp, struct stat *sb, struct proc *p));
+static int vn_write __P((struct file *fp, struct uio *uio, 
+		struct ucred *cred, int flags, struct proc *p));
+
+struct 	fileops vnops =
+	{ vn_read, vn_write, vn_ioctl, vn_poll, vn_statfile, vn_closefile };
+
+/*
+ * Common code for vnode open operations.
+ * Check permissions, and call the VOP_OPEN or VOP_CREATE routine.
+ */
+int
+vn_open(ndp, fmode, cmode)
+	register struct nameidata *ndp;
+	int fmode, cmode;
+{
+	register struct vnode *vp;
+	register struct proc *p = ndp->ni_cnd.cn_proc;
+	register struct ucred *cred = p->p_ucred;
+	struct vattr vat;
+	struct vattr *vap = &vat;
+	int mode, error;
+
+	if (fmode & O_CREAT) {
+		ndp->ni_cnd.cn_nameiop = CREATE;
+		ndp->ni_cnd.cn_flags = LOCKPARENT | LOCKLEAF;
+		if ((fmode & O_EXCL) == 0 && (fmode & O_NOFOLLOW) == 0)
+			ndp->ni_cnd.cn_flags |= FOLLOW;
+		error = namei(ndp);
+		if (error)
+			return (error);
+		if (ndp->ni_vp == NULL) {
+			VATTR_NULL(vap);
+			vap->va_type = VREG;
+			vap->va_mode = cmode;
+			if (fmode & O_EXCL)
+				vap->va_vaflags |= VA_EXCLUSIVE;
+			VOP_LEASE(ndp->ni_dvp, p, cred, LEASE_WRITE);
+			error = VOP_CREATE(ndp->ni_dvp, &ndp->ni_vp,
+					   &ndp->ni_cnd, vap);
+			vput(ndp->ni_dvp);
+			if (error)
+				return (error);
+			ASSERT_VOP_UNLOCKED(ndp->ni_dvp, "create");
+			ASSERT_VOP_LOCKED(ndp->ni_vp, "create");
+			fmode &= ~O_TRUNC;
+			vp = ndp->ni_vp;
+		} else {
+			VOP_ABORTOP(ndp->ni_dvp, &ndp->ni_cnd);
+			if (ndp->ni_dvp == ndp->ni_vp)
+				vrele(ndp->ni_dvp);
+			else
+				vput(ndp->ni_dvp);
+			ndp->ni_dvp = NULL;
+			vp = ndp->ni_vp;
+			if (fmode & O_EXCL) {
+				error = EEXIST;
+				goto bad;
+			}
+			fmode &= ~O_CREAT;
+		}
+	} else {
+		ndp->ni_cnd.cn_nameiop = LOOKUP;
+		ndp->ni_cnd.cn_flags =
+		    ((fmode & O_NOFOLLOW) ? NOFOLLOW : FOLLOW) | LOCKLEAF;
+		error = namei(ndp);
+		if (error)
+			return (error);
+		vp = ndp->ni_vp;
+	}
+	if (vp->v_type == VLNK) {
+		error = EMLINK;
+		goto bad;
+	}
+	if (vp->v_type == VSOCK) {
+		error = EOPNOTSUPP;
+		goto bad;
+	}
+	if ((fmode & O_CREAT) == 0) {
+		mode = 0;
+		if (fmode & (FWRITE | O_TRUNC)) {
+			if (vp->v_type == VDIR) {
+				error = EISDIR;
+				goto bad;
+			}
+			error = vn_writechk(vp);
+			if (error)
+				goto bad;
+			mode |= VWRITE;
+		}
+		if (fmode & FREAD)
+			mode |= VREAD;
+		if (mode) {
+		        error = VOP_ACCESS(vp, mode, cred, p);
+			if (error)
+				goto bad;
+		}
+	}
+	if (fmode & O_TRUNC) {
+		VOP_UNLOCK(vp, 0, p);				/* XXX */
+		VOP_LEASE(vp, p, cred, LEASE_WRITE);
+		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);	/* XXX */
+		VATTR_NULL(vap);
+		vap->va_size = 0;
+		error = VOP_SETATTR(vp, vap, cred, p);
+		if (error)
+			goto bad;
+	}
+	error = VOP_OPEN(vp, fmode, cred, p);
+	if (error)
+		goto bad;
+	/*
+	 * Make sure that a VM object is created for VMIO support.
+	 */
+	if (vn_canvmio(vp) == TRUE) {
+		if ((error = vfs_object_create(vp, p, cred)) != 0)
+			goto bad;
+	}
+
+	if (fmode & FWRITE)
+		vp->v_writecount++;
+	return (0);
+bad:
+	vput(vp);
+	return (error);
+}
+
+/*
+ * Check for write permissions on the specified vnode.
+ * Prototype text segments cannot be written.
+ */
+int
+vn_writechk(vp)
+	register struct vnode *vp;
+{
+
+	/*
+	 * If there's shared text associated with
+	 * the vnode, try to free it up once.  If
+	 * we fail, we can't allow writing.
+	 */
+	if (vp->v_flag & VTEXT)
+		return (ETXTBSY);
+	return (0);
+}
+
+/*
+ * Vnode close call
+ */
+int
+vn_close(vp, flags, cred, p)
+	register struct vnode *vp;
+	int flags;
+	struct ucred *cred;
+	struct proc *p;
+{
+	int error;
+
+	if (flags & FWRITE)
+		vp->v_writecount--;
+	error = VOP_CLOSE(vp, flags, cred, p);
+	vrele(vp);
+	return (error);
+}
+
+/*
+ * Package up an I/O request on a vnode into a uio and do it.
+ */
+int
+vn_rdwr(rw, vp, base, len, offset, segflg, ioflg, cred, aresid, p)
+	enum uio_rw rw;
+	struct vnode *vp;
+	caddr_t base;
+	int len;
+	off_t offset;
+	enum uio_seg segflg;
+	int ioflg;
+	struct ucred *cred;
+	int *aresid;
+	struct proc *p;
+{
+	struct uio auio;
+	struct iovec aiov;
+	int error;
+
+	if ((ioflg & IO_NODELOCKED) == 0)
+		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
+	auio.uio_iov = &aiov;
+	auio.uio_iovcnt = 1;
+	aiov.iov_base = base;
+	aiov.iov_len = len;
+	auio.uio_resid = len;
+	auio.uio_offset = offset;
+	auio.uio_segflg = segflg;
+	auio.uio_rw = rw;
+	auio.uio_procp = p;
+	if (rw == UIO_READ) {
+		error = VOP_READ(vp, &auio, ioflg, cred);
+	} else {
+		error = VOP_WRITE(vp, &auio, ioflg, cred);
+	}
+	if (aresid)
+		*aresid = auio.uio_resid;
+	else
+		if (auio.uio_resid && error == 0)
+			error = EIO;
+	if ((ioflg & IO_NODELOCKED) == 0)
+		VOP_UNLOCK(vp, 0, p);
+	return (error);
+}
+
+/*
+ * File table vnode read routine.
+ */
+static int
+vn_read(fp, uio, cred, flags, p)
+	struct file *fp;
+	struct uio *uio;
+	struct ucred *cred;
+	struct proc *p;
+	int flags;
+{
+	struct vnode *vp;
+	int error, ioflag;
+
+	KASSERT(uio->uio_procp == p, ("uio_procp %p is not p %p",
+	    uio->uio_procp, p));
+	vp = (struct vnode *)fp->f_data;
+	ioflag = 0;
+	if (fp->f_flag & FNONBLOCK)
+		ioflag |= IO_NDELAY;
+	VOP_LEASE(vp, p, cred, LEASE_READ);
+	vn_lock(vp, LK_SHARED | LK_NOPAUSE | LK_RETRY, p);
+	if ((flags & FOF_OFFSET) == 0)
+		uio->uio_offset = fp->f_offset;
+
+	/*
+	 * Sequential read heuristic.
+	 * If we have been doing sequential input,
+	 * a rewind operation doesn't turn off
+	 * sequential input mode.
+	 */
+	if ((uio->uio_offset == 0 && fp->f_seqcount > 0) ||
+	    uio->uio_offset == fp->f_nextread) {
+		int tmpseq = fp->f_seqcount;
+		/*
+		 * XXX we assume that the filesystem block size is
+		 * the default.  Not true, but still gives us a pretty
+		 * good indicator of how sequential the read operations
+		 * are.
+		 */
+		tmpseq += (uio->uio_resid + BKVASIZE - 1) / BKVASIZE;
+		if (tmpseq >= 127)
+			tmpseq = 127;
+		fp->f_seqcount = tmpseq;
+		ioflag |= fp->f_seqcount << 16;
+	} else {
+		if (fp->f_seqcount > 1)
+			fp->f_seqcount = 1;
+		else
+			fp->f_seqcount = 0;
+	}
+	error = VOP_READ(vp, uio, ioflag, cred);
+	if ((flags & FOF_OFFSET) == 0)
+		fp->f_offset = uio->uio_offset;
+	fp->f_nextread = uio->uio_offset;
+	VOP_UNLOCK(vp, 0, p);
+	return (error);
+}
+
+/*
+ * File table vnode write routine.
+ */
+static int
+vn_write(fp, uio, cred, flags, p)
+	struct file *fp;
+	struct uio *uio;
+	struct ucred *cred;
+	struct proc *p;
+	int flags;
+{
+	struct vnode *vp;
+	int error, ioflag;
+
+	KASSERT(uio->uio_procp == p, ("uio_procp %p is not p %p",
+	    uio->uio_procp, p));
+	vp = (struct vnode *)fp->f_data;
+	if (vp->v_type == VREG)
+		bwillwrite();
+	vp = (struct vnode *)fp->f_data;	/* XXX needed? */
+	ioflag = IO_UNIT;
+	if (vp->v_type == VREG && (fp->f_flag & O_APPEND))
+		ioflag |= IO_APPEND;
+	if (fp->f_flag & FNONBLOCK)
+		ioflag |= IO_NDELAY;
+	if ((fp->f_flag & O_FSYNC) ||
+	    (vp->v_mount && (vp->v_mount->mnt_flag & MNT_SYNCHRONOUS)))
+		ioflag |= IO_SYNC;
+	VOP_LEASE(vp, p, cred, LEASE_WRITE);
+	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
+	if ((flags & FOF_OFFSET) == 0)
+		uio->uio_offset = fp->f_offset;
+	error = VOP_WRITE(vp, uio, ioflag, cred);
+	if ((flags & FOF_OFFSET) == 0)
+		fp->f_offset = uio->uio_offset;
+	VOP_UNLOCK(vp, 0, p);
+	return (error);
+}
+
+/*
+ * File table vnode stat routine.
+ */
+static int
+vn_statfile(fp, sb, p)
+	struct file *fp;
+	struct stat *sb;
+	struct proc *p;
+{
+	struct vnode *vp = (struct vnode *)fp->f_data;
+
+	return vn_stat(vp, sb, p);
+}
+
+int
+vn_stat(vp, sb, p)
+	struct vnode *vp;
+	register struct stat *sb;
+	struct proc *p;
+{
+	struct vattr vattr;
+	register struct vattr *vap;
+	int error;
+	u_short mode;
+
+	vap = &vattr;
+	error = VOP_GETATTR(vp, vap, p->p_ucred, p);
+	if (error)
+		return (error);
+
+	/*
+	 * Zero the spare stat fields
+	 */
+	sb->st_lspare = 0;
+	sb->st_qspare[0] = 0;
+	sb->st_qspare[1] = 0;
+
+	/*
+	 * Copy from vattr table
+	 */
+	if (vap->va_fsid != VNOVAL)
+		sb->st_dev = vap->va_fsid;
+	else
+		sb->st_dev = vp->v_mount->mnt_stat.f_fsid.val[0];
+	sb->st_ino = vap->va_fileid;
+	mode = vap->va_mode;
+	switch (vap->va_type) {
+	case VREG:
+		mode |= S_IFREG;
+		break;
+	case VDIR:
+		mode |= S_IFDIR;
+		break;
+	case VBLK:
+		mode |= S_IFBLK;
+		break;
+	case VCHR:
+		mode |= S_IFCHR;
+		break;
+	case VLNK:
+		mode |= S_IFLNK;
+		/* This is a cosmetic change, symlinks do not have a mode. */
+		if (vp->v_mount->mnt_flag & MNT_NOSYMFOLLOW)
+			sb->st_mode &= ~ACCESSPERMS;	/* 0000 */
+		else
+			sb->st_mode |= ACCESSPERMS;	/* 0777 */
+		break;
+	case VSOCK:
+		mode |= S_IFSOCK;
+		break;
+	case VFIFO:
+		mode |= S_IFIFO;
+		break;
+	default:
+		return (EBADF);
+	};
+	sb->st_mode = mode;
+	sb->st_nlink = vap->va_nlink;
+	sb->st_uid = vap->va_uid;
+	sb->st_gid = vap->va_gid;
+	sb->st_rdev = vap->va_rdev;
+	sb->st_size = vap->va_size;
+	sb->st_atimespec = vap->va_atime;
+	sb->st_mtimespec = vap->va_mtime;
+	sb->st_ctimespec = vap->va_ctime;
+
+        /*
+	 * According to www.opengroup.org, the meaning of st_blksize is 
+	 *   "a filesystem-specific preferred I/O block size for this 
+	 *    object.  In some filesystem types, this may vary from file
+	 *    to file"
+	 * Default to zero to catch bogus uses of this field.
+	 */
+
+	if (vap->va_type == VREG) {
+		sb->st_blksize = vap->va_blocksize;
+	} else if ((vp->v_type == VBLK || vp->v_type == VCHR) &&
+	    devsw(vp->v_rdev) && (devsw(vp->v_rdev)->d_flags & D_DISK)) {
+		/* XXX use vn_isdisk() above once VCHR is also disk */
+		sb->st_blksize = vp->v_rdev->si_bsize_best;
+		if (sb->st_blksize < vp->v_rdev->si_bsize_phys)
+			sb->st_blksize = vp->v_rdev->si_bsize_phys;
+		if (sb->st_blksize < BLKDEV_IOSIZE)
+			sb->st_blksize = BLKDEV_IOSIZE;
+	} else {
+		sb->st_blksize = 0;
+	}
+	
+	sb->st_flags = vap->va_flags;
+	if (suser_xxx(p->p_ucred, 0, 0))
+		sb->st_gen = 0;
+	else
+		sb->st_gen = vap->va_gen;
+
+#if (S_BLKSIZE == 512)
+	/* Optimize this case */
+	sb->st_blocks = vap->va_bytes >> 9;
+#else
+	sb->st_blocks = vap->va_bytes / S_BLKSIZE;
+#endif
+	return (0);
+}
+
+/*
+ * File table vnode ioctl routine.
+ */
+static int
+vn_ioctl(fp, com, data, p)
+	struct file *fp;
+	u_long com;
+	caddr_t data;
+	struct proc *p;
+{
+	register struct vnode *vp = ((struct vnode *)fp->f_data);
+	struct vattr vattr;
+	int error;
+
+	switch (vp->v_type) {
+
+	case VREG:
+	case VDIR:
+		if (com == FIONREAD) {
+			error = VOP_GETATTR(vp, &vattr, p->p_ucred, p);
+			if (error)
+				return (error);
+			*(int *)data = vattr.va_size - fp->f_offset;
+			return (0);
+		}
+		if (com == FIONBIO || com == FIOASYNC)	/* XXX */
+			return (0);			/* XXX */
+		/* fall into ... */
+
+	default:
+#if 0
+		return (ENOTTY);
+#endif
+	case VFIFO:
+	case VCHR:
+	case VBLK:
+		if (com == FIODTYPE) {
+			if (vp->v_type != VCHR && vp->v_type != VBLK)
+				return (ENOTTY);
+			*(int *)data = devsw(vp->v_rdev)->d_flags & D_TYPEMASK;
+			return (0);
+		}
+		error = VOP_IOCTL(vp, com, data, fp->f_flag, p->p_ucred, p);
+		if (error == 0 && com == TIOCSCTTY) {
+
+			/* Do nothing if reassigning same control tty */
+			if (p->p_session->s_ttyvp == vp)
+				return (0);
+
+			/* Get rid of reference to old control tty */
+			if (p->p_session->s_ttyvp)
+				vrele(p->p_session->s_ttyvp);
+
+			p->p_session->s_ttyvp = vp;
+			VREF(vp);
+		}
+		return (error);
+	}
+}
+
+/*
+ * File table vnode poll routine.
+ */
+static int
+vn_poll(fp, events, cred, p)
+	struct file *fp;
+	int events;
+	struct ucred *cred;
+	struct proc *p;
+{
+
+	return (VOP_POLL(((struct vnode *)fp->f_data), events, cred, p));
+}
+
+/*
+ * Check that the vnode is still valid, and if so
+ * acquire requested lock.
+ */
+int
+#ifndef	DEBUG_LOCKS
+vn_lock(vp, flags, p)
+#else
+debug_vn_lock(vp, flags, p, filename, line)
+#endif
+	struct vnode *vp;
+	int flags;
+	struct proc *p;
+#ifdef	DEBUG_LOCKS
+	const char *filename;
+	int line;
+#endif
+{
+	int error;
+	
+	do {
+		if ((flags & LK_INTERLOCK) == 0)
+			simple_lock(&vp->v_interlock);
+		if (vp->v_flag & VXLOCK) {
+			vp->v_flag |= VXWANT;
+			simple_unlock(&vp->v_interlock);
+			tsleep((caddr_t)vp, PINOD, "vn_lock", 0);
+			error = ENOENT;
+		} else {
+#ifdef	DEBUG_LOCKS
+			vp->filename = filename;
+			vp->line = line;
+#endif
+			error = VOP_LOCK(vp,
+				    flags | LK_NOPAUSE | LK_INTERLOCK, p);
+			if (error == 0)
+				return (error);
+		}
+		flags &= ~LK_INTERLOCK;
+	} while (flags & LK_RETRY);
+	return (error);
+}
+
+/*
+ * File table vnode close routine.
+ */
+static int
+vn_closefile(fp, p)
+	struct file *fp;
+	struct proc *p;
+{
+
+	fp->f_ops = &badfileops;
+	return (vn_close(((struct vnode *)fp->f_data), fp->f_flag,
+		fp->f_cred, p));
+}