xref: /titanic_54/usr/src/uts/common/fs/vnode.c (revision fa9e4066f08beec538e775443c5be79dd423fcab)

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*	Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T	*/
/*	  All Rights Reserved  	*/

/*
 * University Copyright- Copyright (c) 1982, 1986, 1988
 * The Regents of the University of California
 * All Rights Reserved
 *
 * University Acknowledgment- Portions of this document are derived from
 * software developed by the University of California, Berkeley, and its
 * contributors.
 */


#pragma ident	"%Z%%M%	%I%	%E% SMI"

#include <sys/types.h>
#include <sys/param.h>
#include <sys/t_lock.h>
#include <sys/errno.h>
#include <sys/cred.h>
#include <sys/user.h>
#include <sys/uio.h>
#include <sys/file.h>
#include <sys/pathname.h>
#include <sys/vfs.h>
#include <sys/vnode.h>
#include <sys/rwstlock.h>
#include <sys/fem.h>
#include <sys/stat.h>
#include <sys/mode.h>
#include <sys/conf.h>
#include <sys/sysmacros.h>
#include <sys/cmn_err.h>
#include <sys/systm.h>
#include <sys/kmem.h>
#include <sys/debug.h>
#include <c2/audit.h>
#include <sys/acl.h>
#include <sys/nbmlock.h>
#include <sys/fcntl.h>
#include <fs/fs_subr.h>

/* Determine if this vnode is a file that is read-only */
#define	ISROFILE(vp)	\
	((vp)->v_type != VCHR && (vp)->v_type != VBLK && \
	    (vp)->v_type != VFIFO && vn_is_readonly(vp))

/* Tunable via /etc/system; used only by admin/install */
int nfs_global_client_only;

/*
 * Convert stat(2) formats to vnode types and vice versa.  (Knows about
 * numerical order of S_IFMT and vnode types.)
 */
enum vtype iftovt_tab[] = {
	VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON,
	VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VNON
};

ushort_t vttoif_tab[] = {
	0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK, S_IFIFO,
	S_IFDOOR, 0, S_IFSOCK, S_IFPORT, 0
};

/*
 * The system vnode cache.
 */

kmem_cache_t *vn_cache;


/*
 * Vnode operations vector.
 */

static const fs_operation_trans_def_t vn_ops_table[] = {
	VOPNAME_OPEN, offsetof(struct vnodeops, vop_open),
	    fs_nosys, fs_nosys,

	VOPNAME_CLOSE, offsetof(struct vnodeops, vop_close),
	    fs_nosys, fs_nosys,

	VOPNAME_READ, offsetof(struct vnodeops, vop_read),
	    fs_nosys, fs_nosys,

	VOPNAME_WRITE, offsetof(struct vnodeops, vop_write),
	    fs_nosys, fs_nosys,

	VOPNAME_IOCTL, offsetof(struct vnodeops, vop_ioctl),
	    fs_nosys, fs_nosys,

	VOPNAME_SETFL, offsetof(struct vnodeops, vop_setfl),
	    fs_setfl, fs_nosys,

	VOPNAME_GETATTR, offsetof(struct vnodeops, vop_getattr),
	    fs_nosys, fs_nosys,

	VOPNAME_SETATTR, offsetof(struct vnodeops, vop_setattr),
	    fs_nosys, fs_nosys,

	VOPNAME_ACCESS, offsetof(struct vnodeops, vop_access),
	    fs_nosys, fs_nosys,

	VOPNAME_LOOKUP, offsetof(struct vnodeops, vop_lookup),
	    fs_nosys, fs_nosys,

	VOPNAME_CREATE, offsetof(struct vnodeops, vop_create),
	    fs_nosys, fs_nosys,

	VOPNAME_REMOVE, offsetof(struct vnodeops, vop_remove),
	    fs_nosys, fs_nosys,

	VOPNAME_LINK, offsetof(struct vnodeops, vop_link),
	    fs_nosys, fs_nosys,

	VOPNAME_RENAME, offsetof(struct vnodeops, vop_rename),
	    fs_nosys, fs_nosys,

	VOPNAME_MKDIR, offsetof(struct vnodeops, vop_mkdir),
	    fs_nosys, fs_nosys,

	VOPNAME_RMDIR, offsetof(struct vnodeops, vop_rmdir),
	    fs_nosys, fs_nosys,

	VOPNAME_READDIR, offsetof(struct vnodeops, vop_readdir),
	    fs_nosys, fs_nosys,

	VOPNAME_SYMLINK, offsetof(struct vnodeops, vop_symlink),
	    fs_nosys, fs_nosys,

	VOPNAME_READLINK, offsetof(struct vnodeops, vop_readlink),
	    fs_nosys, fs_nosys,

	VOPNAME_FSYNC, offsetof(struct vnodeops, vop_fsync),
	    fs_nosys, fs_nosys,

	VOPNAME_INACTIVE, offsetof(struct vnodeops, vop_inactive),
	    fs_nosys, fs_nosys,

	VOPNAME_FID, offsetof(struct vnodeops, vop_fid),
	    fs_nosys, fs_nosys,

	VOPNAME_RWLOCK, offsetof(struct vnodeops, vop_rwlock),
	    fs_rwlock, fs_rwlock,

	VOPNAME_RWUNLOCK, offsetof(struct vnodeops, vop_rwunlock),
	    (fs_generic_func_p) fs_rwunlock,
	    (fs_generic_func_p) fs_rwunlock,	/* no errors allowed */

	VOPNAME_SEEK, offsetof(struct vnodeops, vop_seek),
	    fs_nosys, fs_nosys,

	VOPNAME_CMP, offsetof(struct vnodeops, vop_cmp),
	    fs_cmp, fs_cmp,		/* no errors allowed */

	VOPNAME_FRLOCK, offsetof(struct vnodeops, vop_frlock),
	    fs_frlock, fs_nosys,

	VOPNAME_SPACE, offsetof(struct vnodeops, vop_space),
	    fs_nosys, fs_nosys,

	VOPNAME_REALVP, offsetof(struct vnodeops, vop_realvp),
	    fs_nosys, fs_nosys,

	VOPNAME_GETPAGE, offsetof(struct vnodeops, vop_getpage),
	    fs_nosys, fs_nosys,

	VOPNAME_PUTPAGE, offsetof(struct vnodeops, vop_putpage),
	    fs_nosys, fs_nosys,

	VOPNAME_MAP, offsetof(struct vnodeops, vop_map),
	    (fs_generic_func_p) fs_nosys_map,
	    (fs_generic_func_p) fs_nosys_map,

	VOPNAME_ADDMAP, offsetof(struct vnodeops, vop_addmap),
	    (fs_generic_func_p) fs_nosys_addmap,
	    (fs_generic_func_p) fs_nosys_addmap,

	VOPNAME_DELMAP, offsetof(struct vnodeops, vop_delmap),
	    fs_nosys, fs_nosys,

	VOPNAME_POLL, offsetof(struct vnodeops, vop_poll),
	    (fs_generic_func_p) fs_poll, (fs_generic_func_p) fs_nosys_poll,

	VOPNAME_DUMP, offsetof(struct vnodeops, vop_dump),
	    fs_nosys, fs_nosys,

	VOPNAME_PATHCONF, offsetof(struct vnodeops, vop_pathconf),
	    fs_pathconf, fs_nosys,

	VOPNAME_PAGEIO, offsetof(struct vnodeops, vop_pageio),
	    fs_nosys, fs_nosys,

	VOPNAME_DUMPCTL, offsetof(struct vnodeops, vop_dumpctl),
	    fs_nosys, fs_nosys,

	VOPNAME_DISPOSE, offsetof(struct vnodeops, vop_dispose),
	    (fs_generic_func_p) fs_dispose,
	    (fs_generic_func_p) fs_nodispose,

	VOPNAME_SETSECATTR, offsetof(struct vnodeops, vop_setsecattr),
	    fs_nosys, fs_nosys,

	VOPNAME_GETSECATTR, offsetof(struct vnodeops, vop_getsecattr),
	    fs_fab_acl, fs_nosys,

	VOPNAME_SHRLOCK, offsetof(struct vnodeops, vop_shrlock),
	    fs_shrlock, fs_nosys,

	VOPNAME_VNEVENT, offsetof(struct vnodeops, vop_vnevent),
	    (fs_generic_func_p) fs_vnevent_nosupport,
	    (fs_generic_func_p) fs_vnevent_nosupport,

	NULL, 0, NULL, NULL
};


/*
 * Read or write a vnode.  Called from kernel code.
 */
int
vn_rdwr(
	enum uio_rw rw,
	struct vnode *vp,
	caddr_t base,
	ssize_t len,
	offset_t offset,
	enum uio_seg seg,
	int ioflag,
	rlim64_t ulimit,	/* meaningful only if rw is UIO_WRITE */
	cred_t *cr,
	ssize_t *residp)
{
	struct uio uio;
	struct iovec iov;
	int error;
	int in_crit = 0;

	if (rw == UIO_WRITE && ISROFILE(vp))
		return (EROFS);

	if (len < 0)
		return (EIO);

	iov.iov_base = base;
	iov.iov_len = len;
	uio.uio_iov = &iov;
	uio.uio_iovcnt = 1;
	uio.uio_loffset = offset;
	uio.uio_segflg = (short)seg;
	uio.uio_resid = len;
	uio.uio_llimit = ulimit;

	/*
	 * We have to enter the critical region before calling VOP_RWLOCK
	 * to avoid a deadlock with ufs.
	 */
	if (nbl_need_check(vp)) {
		int svmand;

		nbl_start_crit(vp, RW_READER);
		in_crit = 1;
		error = nbl_svmand(vp, cr, &svmand);
		if (error != 0)
			goto done;
		if (nbl_conflict(vp, rw == UIO_WRITE ? NBL_WRITE : NBL_READ,
		    uio.uio_offset, uio.uio_resid, svmand)) {
			error = EACCES;
			goto done;
		}
	}

	(void) VOP_RWLOCK(vp,
		rw == UIO_WRITE ? V_WRITELOCK_TRUE : V_WRITELOCK_FALSE, NULL);
	if (rw == UIO_WRITE) {
		uio.uio_fmode = FWRITE;
		uio.uio_extflg = UIO_COPY_DEFAULT;
		error = VOP_WRITE(vp, &uio, ioflag, cr, NULL);
	} else {
		uio.uio_fmode = FREAD;
		uio.uio_extflg = UIO_COPY_CACHED;
		error = VOP_READ(vp, &uio, ioflag, cr, NULL);
	}
	VOP_RWUNLOCK(vp, rw == UIO_WRITE ? V_WRITELOCK_TRUE : V_WRITELOCK_FALSE,
									NULL);
	if (residp)
		*residp = uio.uio_resid;
	else if (uio.uio_resid)
		error = EIO;

done:
	if (in_crit)
		nbl_end_crit(vp);
	return (error);
}

/*
 * Release a vnode.  Call VOP_INACTIVE on last reference or
 * decrement reference count.
 *
 * To avoid race conditions, the v_count is left at 1 for
 * the call to VOP_INACTIVE. This prevents another thread
 * from reclaiming and releasing the vnode *before* the
 * VOP_INACTIVE routine has a chance to destroy the vnode.
 * We can't have more than 1 thread calling VOP_INACTIVE
 * on a vnode.
 */
void
vn_rele(vnode_t *vp)
{
	if (vp->v_count == 0)
		cmn_err(CE_PANIC, "vn_rele: vnode ref count 0");
	mutex_enter(&vp->v_lock);
	if (vp->v_count == 1) {
		mutex_exit(&vp->v_lock);
		VOP_INACTIVE(vp, CRED());
	} else {
		vp->v_count--;
		mutex_exit(&vp->v_lock);
	}
}

/*
 * Like vn_rele() except that it clears v_stream under v_lock.
 * This is used by sockfs when it dismantels the association between
 * the sockfs node and the vnode in the underlaying file system.
 * v_lock has to be held to prevent a thread coming through the lookupname
 * path from accessing a stream head that is going away.
 */
void
vn_rele_stream(vnode_t *vp)
{
	if (vp->v_count == 0)
		cmn_err(CE_PANIC, "vn_rele: vnode ref count 0");
	mutex_enter(&vp->v_lock);
	vp->v_stream = NULL;
	if (vp->v_count == 1) {
		mutex_exit(&vp->v_lock);
		VOP_INACTIVE(vp, CRED());
	} else {
		vp->v_count--;
		mutex_exit(&vp->v_lock);
	}
}

int
vn_open(
	char *pnamep,
	enum uio_seg seg,
	int filemode,
	int createmode,
	struct vnode **vpp,
	enum create crwhy,
	mode_t umask)
{
	return (vn_openat(pnamep, seg, filemode,
			createmode, vpp, crwhy, umask, NULL));
}


/*
 * Open/create a vnode.
 * This may be callable by the kernel, the only known use
 * of user context being that the current user credentials
 * are used for permissions.  crwhy is defined iff filemode & FCREAT.
 */
int
vn_openat(
	char *pnamep,
	enum uio_seg seg,
	int filemode,
	int createmode,
	struct vnode **vpp,
	enum create crwhy,
	mode_t umask,
	struct vnode *startvp)
{
	struct vnode *vp;
	int mode;
	int error;
	int in_crit = 0;
	struct vattr vattr;
	enum symfollow follow;

	mode = 0;
	if (filemode & FREAD)
		mode |= VREAD;
	if (filemode & (FWRITE|FTRUNC))
		mode |= VWRITE;

	/* symlink interpretation */
	if (filemode & FNOFOLLOW)
		follow = NO_FOLLOW;
	else
		follow = FOLLOW;

top:
	if (filemode & FCREAT) {
		enum vcexcl excl;

		/*
		 * Wish to create a file.
		 */
		vattr.va_type = VREG;
		vattr.va_mode = createmode;
		vattr.va_mask = AT_TYPE|AT_MODE;
		if (filemode & FTRUNC) {
			vattr.va_size = 0;
			vattr.va_mask |= AT_SIZE;
		}
		if (filemode & FEXCL)
			excl = EXCL;
		else
			excl = NONEXCL;

		if (error =
		    vn_createat(pnamep, seg, &vattr, excl, mode, &vp, crwhy,
					(filemode & ~(FTRUNC|FEXCL)),
						umask, startvp))
			return (error);
	} else {
		/*
		 * Wish to open a file.  Just look it up.
		 */
		if (error = lookupnameat(pnamep, seg, follow,
		    NULLVPP, &vp, startvp)) {
			if (error == ESTALE)
				goto top;
			return (error);
		}

		/*
		 * Get the attributes to check whether file is large.
		 * We do this only if the FOFFMAX flag is not set and
		 * only for regular files.
		 */

		if (!(filemode & FOFFMAX) && (vp->v_type == VREG)) {
			vattr.va_mask = AT_SIZE;
			if ((error = VOP_GETATTR(vp, &vattr, 0, CRED()))) {
				goto out;
			}
			if (vattr.va_size > (u_offset_t)MAXOFF32_T) {
				/*
				 * Large File API - regular open fails
				 * if FOFFMAX flag is set in file mode
				 */
				error = EOVERFLOW;
				goto out;
			}
		}
		/*
		 * Can't write directories, active texts, or
		 * read-only filesystems.  Can't truncate files
		 * on which mandatory locking is in effect.
		 */
		if (filemode & (FWRITE|FTRUNC)) {
			/*
			 * Allow writable directory if VDIROPEN flag is set.
			 */
			if (vp->v_type == VDIR && !(vp->v_flag & VDIROPEN)) {
				error = EISDIR;
				goto out;
			}
			if (ISROFILE(vp)) {
				error = EROFS;
				goto out;
			}
			/*
			 * Can't truncate files on which mandatory locking
			 * or non-blocking mandatory locking is in effect.
			 */
			if (filemode & FTRUNC) {
				vnode_t *rvp;

				if (VOP_REALVP(vp, &rvp) != 0)
					rvp = vp;
				if (nbl_need_check(vp)) {
					nbl_start_crit(vp, RW_READER);
					in_crit = 1;
					vattr.va_mask = AT_MODE|AT_SIZE;
					if ((error = VOP_GETATTR(vp, &vattr, 0,
					    CRED())) == 0) {
						if (rvp->v_filocks != NULL)
							if (MANDLOCK(vp,
							    vattr.va_mode))
								error = EAGAIN;
						if (!error) {
							if (nbl_conflict(vp,
							    NBL_WRITE, 0,
							    vattr.va_size, 0))
								error = EACCES;
						}
					}
				} else if (rvp->v_filocks != NULL) {
					vattr.va_mask = AT_MODE;
					if ((error = VOP_GETATTR(vp, &vattr,
					    0, CRED())) == 0 && MANDLOCK(vp,
					    vattr.va_mode))
						error = EAGAIN;
				}
			}
			if (error)
				goto out;
		}
		/*
		 * Check permissions.
		 */
		if (error = VOP_ACCESS(vp, mode, 0, CRED()))
			goto out;
	}

	/*
	 * Do remaining checks for FNOFOLLOW and FNOLINKS.
	 */
	if ((filemode & FNOFOLLOW) && vp->v_type == VLNK) {
		error = EINVAL;
		goto out;
	}
	if (filemode & FNOLINKS) {
		vattr.va_mask = AT_NLINK;
		if ((error = VOP_GETATTR(vp, &vattr, 0, CRED()))) {
			goto out;
		}
		if (vattr.va_nlink != 1) {
			error = EMLINK;
			goto out;
		}
	}

	/*
	 * Opening a socket corresponding to the AF_UNIX pathname
	 * in the filesystem name space is not supported.
	 * However, VSOCK nodes in namefs are supported in order
	 * to make fattach work for sockets.
	 *
	 * XXX This uses VOP_REALVP to distinguish between
	 * an unopened namefs node (where VOP_REALVP returns a
	 * different VSOCK vnode) and a VSOCK created by vn_create
	 * in some file system (where VOP_REALVP would never return
	 * a different vnode).
	 */
	if (vp->v_type == VSOCK) {
		struct vnode *nvp;

		error = VOP_REALVP(vp, &nvp);
		if (error != 0 || nvp == NULL || nvp == vp ||
		    nvp->v_type != VSOCK) {
			error = EOPNOTSUPP;
			goto out;
		}
	}
	/*
	 * Do opening protocol.
	 */
	error = VOP_OPEN(&vp, filemode, CRED());
	/*
	 * Truncate if required.
	 */
	if (error == 0 && (filemode & FTRUNC) && !(filemode & FCREAT)) {
		vattr.va_size = 0;
		vattr.va_mask = AT_SIZE;
		if ((error = VOP_SETATTR(vp, &vattr, 0, CRED(), NULL)) != 0)
			(void) VOP_CLOSE(vp, filemode, 1, (offset_t)0, CRED());
	}
out:
	ASSERT(vp->v_count > 0);

	if (in_crit) {
		nbl_end_crit(vp);
		in_crit = 0;
	}
	if (error) {
		/*
		 * The following clause was added to handle a problem
		 * with NFS consistency.  It is possible that a lookup
		 * of the file to be opened succeeded, but the file
		 * itself doesn't actually exist on the server.  This
		 * is chiefly due to the DNLC containing an entry for
		 * the file which has been removed on the server.  In
		 * this case, we just start over.  If there was some
		 * other cause for the ESTALE error, then the lookup
		 * of the file will fail and the error will be returned
		 * above instead of looping around from here.
		 */
		VN_RELE(vp);
		if (error == ESTALE)
			goto top;
	} else
		*vpp = vp;
	return (error);
}

int
vn_create(
	char *pnamep,
	enum uio_seg seg,
	struct vattr *vap,
	enum vcexcl excl,
	int mode,
	struct vnode **vpp,
	enum create why,
	int flag,
	mode_t umask)
{
	return (vn_createat(pnamep, seg, vap, excl, mode, vpp,
			why, flag, umask, NULL));
}

/*
 * Create a vnode (makenode).
 */
int
vn_createat(
	char *pnamep,
	enum uio_seg seg,
	struct vattr *vap,
	enum vcexcl excl,
	int mode,
	struct vnode **vpp,
	enum create why,
	int flag,
	mode_t umask,
	struct vnode *startvp)
{
	struct vnode *dvp;	/* ptr to parent dir vnode */
	struct vnode *vp = NULL;
	struct pathname pn;
	int error;
	int in_crit = 0;
	struct vattr vattr;
	enum symfollow follow;

	ASSERT((vap->va_mask & (AT_TYPE|AT_MODE)) == (AT_TYPE|AT_MODE));

	/* symlink interpretation */
	if ((flag & FNOFOLLOW) || excl == EXCL)
		follow = NO_FOLLOW;
	else
		follow = FOLLOW;
	flag &= ~(FNOFOLLOW|FNOLINKS);

top:
	/*
	 * Lookup directory.
	 * If new object is a file, call lower level to create it.
	 * Note that it is up to the lower level to enforce exclusive
	 * creation, if the file is already there.
	 * This allows the lower level to do whatever
	 * locking or protocol that is needed to prevent races.
	 * If the new object is directory call lower level to make
	 * the new directory, with "." and "..".
	 */
	if (error = pn_get(pnamep, seg, &pn))
		return (error);
#ifdef  C2_AUDIT
	if (audit_active)
		audit_vncreate_start();
#endif /* C2_AUDIT */
	dvp = NULL;
	*vpp = NULL;
	/*
	 * lookup will find the parent directory for the vnode.
	 * When it is done the pn holds the name of the entry
	 * in the directory.
	 * If this is a non-exclusive create we also find the node itself.
	 */
	error = lookuppnat(&pn, NULL, follow, &dvp,
	    (excl == EXCL) ? NULLVPP : vpp, startvp);
	if (error) {
		pn_free(&pn);
		if (error == ESTALE)
			goto top;
		if (why == CRMKDIR && error == EINVAL)
			error = EEXIST;		/* SVID */
		return (error);
	}

	if (why != CRMKNOD)
		vap->va_mode &= ~VSVTX;

	/*
	 * If default ACLs are defined for the directory don't apply the
	 * umask if umask is passed.
	 */

	if (umask) {

		vsecattr_t vsec;

		vsec.vsa_aclcnt = 0;
		vsec.vsa_aclentp = NULL;
		vsec.vsa_dfaclcnt = 0;
		vsec.vsa_dfaclentp = NULL;
		vsec.vsa_mask = VSA_DFACLCNT;
		error =  VOP_GETSECATTR(dvp, &vsec, 0, CRED());
		/*
		 * If error is ENOSYS then treat it as no error
		 * Don't want to force all file systems to support
		 * aclent_t style of ACL's.
		 */
		if (error == ENOSYS)
			error = 0;
		if (error) {
			if (*vpp != NULL)
				VN_RELE(*vpp);
			goto out;
		} else {
			/*
			 * Apply the umask if no default ACLs.
			 */
			if (vsec.vsa_dfaclcnt == 0)
				vap->va_mode &= ~umask;

			/*
			 * VOP_GETSECATTR() may have allocated memory for
			 * ACLs we didn't request, so double-check and
			 * free it if necessary.
			 */
			if (vsec.vsa_aclcnt && vsec.vsa_aclentp != NULL)
				kmem_free((caddr_t)vsec.vsa_aclentp,
				    vsec.vsa_aclcnt * sizeof (aclent_t));
			if (vsec.vsa_dfaclcnt && vsec.vsa_dfaclentp != NULL)
				kmem_free((caddr_t)vsec.vsa_dfaclentp,
				    vsec.vsa_dfaclcnt * sizeof (aclent_t));
		}
	}

	/*
	 * In general we want to generate EROFS if the file system is
	 * readonly.  However, POSIX (IEEE Std. 1003.1) section 5.3.1
	 * documents the open system call, and it says that O_CREAT has no
	 * effect if the file already exists.  Bug 1119649 states
	 * that open(path, O_CREAT, ...) fails when attempting to open an
	 * existing file on a read only file system.  Thus, the first part
	 * of the following if statement has 3 checks:
	 *	if the file exists &&
	 *		it is being open with write access &&
	 *		the file system is read only
	 *	then generate EROFS
	 */
	if ((*vpp != NULL && (mode & VWRITE) && ISROFILE(*vpp)) ||
	    (*vpp == NULL && dvp->v_vfsp->vfs_flag & VFS_RDONLY)) {
		if (*vpp)
			VN_RELE(*vpp);
		error = EROFS;
	} else if (excl == NONEXCL && *vpp != NULL) {
		vnode_t *rvp;

		/*
		 * File already exists.  If a mandatory lock has been
		 * applied, return error.
		 */
		vp = *vpp;
		if (VOP_REALVP(vp, &rvp) != 0)
			rvp = vp;
		if ((vap->va_mask & AT_SIZE) && nbl_need_check(vp)) {
			nbl_start_crit(vp, RW_READER);
			in_crit = 1;
		}
		if (rvp->v_filocks != NULL || rvp->v_shrlocks != NULL) {
			vattr.va_mask = AT_MODE|AT_SIZE;
			if (error = VOP_GETATTR(vp, &vattr, 0, CRED())) {
				goto out;
			}
			if (MANDLOCK(vp, vattr.va_mode)) {
				error = EAGAIN;
				goto out;
			}
			/*
			 * File cannot be truncated if non-blocking mandatory
			 * locks are currently on the file.
			 */
			if ((vap->va_mask & AT_SIZE) && in_crit) {
				u_offset_t offset;
				ssize_t length;

				offset = vap->va_size > vattr.va_size ?
						vattr.va_size : vap->va_size;
				length = vap->va_size > vattr.va_size ?
						vap->va_size - vattr.va_size :
						vattr.va_size - vap->va_size;
				if (nbl_conflict(vp, NBL_WRITE, offset,
						length, 0)) {
					error = EACCES;
					goto out;
				}
			}
		}

		/*
		 * If the file is the root of a VFS, we've crossed a
		 * mount point and the "containing" directory that we
		 * acquired above (dvp) is irrelevant because it's in
		 * a different file system.  We apply VOP_CREATE to the
		 * target itself instead of to the containing directory
		 * and supply a null path name to indicate (conventionally)
		 * the node itself as the "component" of interest.
		 *
		 * The intercession of the file system is necessary to
		 * ensure that the appropriate permission checks are
		 * done.
		 */
		if (vp->v_flag & VROOT) {
			ASSERT(why != CRMKDIR);
			error =
			    VOP_CREATE(vp, "", vap, excl, mode, vpp, CRED(),
				    flag);
			/*
			 * If the create succeeded, it will have created
			 * a new reference to the vnode.  Give up the
			 * original reference.  The assertion should not
			 * get triggered because NBMAND locks only apply to
			 * VREG files.  And if in_crit is non-zero for some
			 * reason, detect that here, rather than when we
			 * deference a null vp.
			 */
			ASSERT(in_crit == 0);
			VN_RELE(vp);
			vp = NULL;
			goto out;
		}

		/*
		 * Large File API - non-large open (FOFFMAX flag not set)
		 * of regular file fails if the file size exceeds MAXOFF32_T.
		 */
		if (why != CRMKDIR &&
		    !(flag & FOFFMAX) &&
		    (vp->v_type == VREG)) {
			vattr.va_mask = AT_SIZE;
			if ((error = VOP_GETATTR(vp, &vattr, 0, CRED()))) {
				goto out;
			}
			if ((vattr.va_size > (u_offset_t)MAXOFF32_T)) {
				error = EOVERFLOW;
				goto out;
			}
		}
	}

	if (error == 0) {
		/*
		 * Call mkdir() if specified, otherwise create().
		 */
		int must_be_dir = pn_fixslash(&pn);	/* trailing '/'? */

		if (why == CRMKDIR)
			error = VOP_MKDIR(dvp, pn.pn_path, vap, vpp, CRED());
		else if (!must_be_dir)
			error = VOP_CREATE(dvp, pn.pn_path, vap,
			    excl, mode, vpp, CRED(), flag);
		else
			error = ENOTDIR;
	}

out:

#ifdef C2_AUDIT
	if (audit_active)
		audit_vncreate_finish(*vpp, error);
#endif  /* C2_AUDIT */
	if (in_crit) {
		nbl_end_crit(vp);
		in_crit = 0;
	}
	if (vp != NULL) {
		VN_RELE(vp);
		vp = NULL;
	}
	pn_free(&pn);
	VN_RELE(dvp);
	/*
	 * The following clause was added to handle a problem
	 * with NFS consistency.  It is possible that a lookup
	 * of the file to be created succeeded, but the file
	 * itself doesn't actually exist on the server.  This
	 * is chiefly due to the DNLC containing an entry for
	 * the file which has been removed on the server.  In
	 * this case, we just start over.  If there was some
	 * other cause for the ESTALE error, then the lookup
	 * of the file will fail and the error will be returned
	 * above instead of looping around from here.
	 */
	if (error == ESTALE)
		goto top;
	return (error);
}

int
vn_link(char *from, char *to, enum uio_seg seg)
{
	struct vnode *fvp;		/* from vnode ptr */
	struct vnode *tdvp;		/* to directory vnode ptr */
	struct pathname pn;
	int error;
	struct vattr vattr;
	dev_t fsid;

top:
	fvp = tdvp = NULL;
	if (error = pn_get(to, seg, &pn))
		return (error);
	if (error = lookupname(from, seg, NO_FOLLOW, NULLVPP, &fvp))
		goto out;
	if (error = lookuppn(&pn, NULL, NO_FOLLOW, &tdvp, NULLVPP))
		goto out;
	/*
	 * Make sure both source vnode and target directory vnode are
	 * in the same vfs and that it is writeable.
	 */
	vattr.va_mask = AT_FSID;
	if (error = VOP_GETATTR(fvp, &vattr, 0, CRED()))
		goto out;
	fsid = vattr.va_fsid;
	vattr.va_mask = AT_FSID;
	if (error = VOP_GETATTR(tdvp, &vattr, 0, CRED()))
		goto out;
	if (fsid != vattr.va_fsid) {
		error = EXDEV;
		goto out;
	}
	if (tdvp->v_vfsp->vfs_flag & VFS_RDONLY) {
		error = EROFS;
		goto out;
	}
	/*
	 * Do the link.
	 */
	(void) pn_fixslash(&pn);
	error = VOP_LINK(tdvp, fvp, pn.pn_path, CRED());
out:
	pn_free(&pn);
	if (fvp)
		VN_RELE(fvp);
	if (tdvp)
		VN_RELE(tdvp);
	if (error == ESTALE)
		goto top;
	return (error);
}

int
vn_rename(char *from, char *to, enum uio_seg seg)
{
	return (vn_renameat(NULL, from, NULL, to, seg));
}

int
vn_renameat(vnode_t *fdvp, char *fname, vnode_t *tdvp,
		char *tname, enum uio_seg seg)
{
	int error;
	struct vattr vattr;
	struct pathname fpn;		/* from pathname */
	struct pathname tpn;		/* to pathname */
	dev_t fsid;
	int in_crit = 0;
	vnode_t *fromvp, *fvp;
	vnode_t *tovp;

top:
	fvp = fromvp = tovp = NULL;
	/*
	 * Get to and from pathnames.
	 */
	if (error = pn_get(fname, seg, &fpn))
		return (error);
	if (error = pn_get(tname, seg, &tpn)) {
		pn_free(&fpn);
		return (error);
	}

	/*
	 * First we need to resolve the correct directories
	 * The passed in directories may only be a starting point,
	 * but we need the real directories the file(s) live in.
	 * For example the fname may be something like usr/lib/sparc
	 * and we were passed in the / directory, but we need to
	 * use the lib directory for the rename.
	 */

#ifdef  C2_AUDIT
	if (audit_active)
		audit_setfsat_path(1);
#endif /* C2_AUDIT */
	/*
	 * Lookup to and from directories.
	 */
	if (error = lookuppnat(&fpn, NULL, NO_FOLLOW, &fromvp, &fvp, fdvp)) {
		goto out;
	}

	/*
	 * Make sure there is an entry.
	 */
	if (fvp == NULL) {
		error = ENOENT;
		goto out;
	}

#ifdef  C2_AUDIT
	if (audit_active)
		audit_setfsat_path(3);
#endif /* C2_AUDIT */
	if (error = lookuppnat(&tpn, NULL, NO_FOLLOW, &tovp, NULLVPP, tdvp)) {
		goto out;
	}

	/*
	 * Make sure both the from vnode directory and the to directory
	 * are in the same vfs and the to directory is writable.
	 * We check fsid's, not vfs pointers, so loopback fs works.
	 */
	if (fromvp != tovp) {
		vattr.va_mask = AT_FSID;
		if (error = VOP_GETATTR(fromvp, &vattr, 0, CRED()))
			goto out;
		fsid = vattr.va_fsid;
		vattr.va_mask = AT_FSID;
		if (error = VOP_GETATTR(tovp, &vattr, 0, CRED()))
			goto out;
		if (fsid != vattr.va_fsid) {
			error = EXDEV;
			goto out;
		}
	}

	if (tovp->v_vfsp->vfs_flag & VFS_RDONLY) {
		error = EROFS;
		goto out;
	}

	if (nbl_need_check(fvp)) {
		nbl_start_crit(fvp, RW_READER);
		in_crit = 1;
		if (nbl_conflict(fvp, NBL_RENAME, 0, 0, 0)) {
			error = EACCES;
			goto out;
		}
	}

	/*
	 * Do the rename.
	 */
	(void) pn_fixslash(&tpn);
	error = VOP_RENAME(fromvp, fpn.pn_path, tovp, tpn.pn_path, CRED());

out:
	pn_free(&fpn);
	pn_free(&tpn);
	if (in_crit) {
		nbl_end_crit(fvp);
		in_crit = 0;
	}
	if (fromvp)
		VN_RELE(fromvp);
	if (tovp)
		VN_RELE(tovp);
	if (fvp)
		VN_RELE(fvp);
	if (error == ESTALE)
		goto top;
	return (error);
}

/*
 * Remove a file or directory.
 */
int
vn_remove(char *fnamep, enum uio_seg seg, enum rm dirflag)
{
	return (vn_removeat(NULL, fnamep, seg, dirflag));
}

int
vn_removeat(vnode_t *startvp, char *fnamep, enum uio_seg seg, enum rm dirflag)
{
	struct vnode *vp;		/* entry vnode */
	struct vnode *dvp;		/* ptr to parent dir vnode */
	struct vnode *coveredvp;
	struct pathname pn;		/* name of entry */
	enum vtype vtype;
	int error;
	struct vfs *vfsp;
	struct vfs *dvfsp;	/* ptr to parent dir vfs */
	int in_crit = 0;

top:
	if (error = pn_get(fnamep, seg, &pn))
		return (error);
	dvp = vp = NULL;
	if (error = lookuppnat(&pn, NULL, NO_FOLLOW, &dvp, &vp, startvp)) {
		pn_free(&pn);
		if (error == ESTALE)
			goto top;
		return (error);
	}

	/*
	 * Make sure there is an entry.
	 */
	if (vp == NULL) {
		error = ENOENT;
		goto out;
	}

	vfsp = vp->v_vfsp;
	dvfsp = dvp->v_vfsp;

	/*
	 * If the named file is the root of a mounted filesystem, fail,
	 * unless it's marked unlinkable.  In that case, unmount the
	 * filesystem and proceed to unlink the covered vnode.  (If the
	 * covered vnode is a directory, use rmdir instead of unlink,
	 * to avoid file system corruption.)
	 */
	if (vp->v_flag & VROOT) {
		if (vfsp->vfs_flag & VFS_UNLINKABLE) {
			if (dirflag == RMDIRECTORY) {
				/*
				 * User called rmdir(2) on a file that has
				 * been namefs mounted on top of.  Since
				 * namefs doesn't allow directories to
				 * be mounted on other files we know
				 * vp is not of type VDIR so fail to operation.
				 */
				error = ENOTDIR;
				goto out;
			}
			coveredvp = vfsp->vfs_vnodecovered;
			VN_HOLD(coveredvp);
			VN_RELE(vp);
			vp = NULL;
			if ((error = vn_vfswlock(coveredvp)) == 0)
				error = dounmount(vfsp, 0, CRED());
			/*
			 * Unmounted the namefs file system; now get
			 * the object it was mounted over.
			 */
			vp = coveredvp;
			/*
			 * If namefs was mounted over a directory, then
			 * we want to use rmdir() instead of unlink().
			 */
			if (vp->v_type == VDIR)
				dirflag = RMDIRECTORY;
		} else
			error = EBUSY;

		if (error)
			goto out;
	}

	/*
	 * Make sure filesystem is writeable.
	 * We check the parent directory's vfs in case this is an lofs vnode.
	 */
	if (dvfsp && dvfsp->vfs_flag & VFS_RDONLY) {
		error = EROFS;
		goto out;
	}

	vtype = vp->v_type;

	/*
	 * If there is the possibility of an nbmand share reservation, make
	 * sure it's okay to remove the file.  Keep a reference to the
	 * vnode, so that we can exit the nbl critical region after
	 * calling VOP_REMOVE.
	 * If there is no possibility of an nbmand share reservation,
	 * release the vnode reference now.  Filesystems like NFS may
	 * behave differently if there is an extra reference, so get rid of
	 * this one.  Fortunately, we can't have nbmand mounts on NFS
	 * filesystems.
	 */
	if (nbl_need_check(vp)) {
		nbl_start_crit(vp, RW_READER);
		in_crit = 1;
		if (nbl_conflict(vp, NBL_REMOVE, 0, 0, 0)) {
			error = EACCES;
			goto out;
		}
	} else {
		VN_RELE(vp);
		vp = NULL;
	}

	if (dirflag == RMDIRECTORY) {
		/*
		 * Caller is using rmdir(2), which can only be applied to
		 * directories.
		 */
		if (vtype != VDIR) {
			error = ENOTDIR;
		} else {
			vnode_t *cwd;
			proc_t *pp = curproc;

			mutex_enter(&pp->p_lock);
			cwd = PTOU(pp)->u_cdir;
			VN_HOLD(cwd);
			mutex_exit(&pp->p_lock);
			error = VOP_RMDIR(dvp, pn.pn_path, cwd, CRED());
			VN_RELE(cwd);
		}
	} else {
		/*
		 * Unlink(2) can be applied to anything.
		 */
		error = VOP_REMOVE(dvp, pn.pn_path, CRED());
	}

out:
	pn_free(&pn);
	if (in_crit) {
		nbl_end_crit(vp);
		in_crit = 0;
	}
	if (vp != NULL)
		VN_RELE(vp);
	if (dvp != NULL)
		VN_RELE(dvp);
	if (error == ESTALE)
		goto top;
	return (error);
}

/*
 * Utility function to compare equality of vnodes.
 * Compare the underlying real vnodes, if there are underlying vnodes.
 * This is a more thorough comparison than the VN_CMP() macro provides.
 */
int
vn_compare(vnode_t *vp1, vnode_t *vp2)
{
	vnode_t *realvp;

	if (vp1 != NULL && VOP_REALVP(vp1, &realvp) == 0)
		vp1 = realvp;
	if (vp2 != NULL && VOP_REALVP(vp2, &realvp) == 0)
		vp2 = realvp;
	return (VN_CMP(vp1, vp2));
}

/*
 * The number of locks to hash into.  This value must be a power
 * of 2 minus 1 and should probably also be prime.
 */
#define	NUM_BUCKETS	1023

struct  vn_vfslocks_bucket {
	kmutex_t vb_lock;
	vn_vfslocks_entry_t *vb_list;
	char pad[64 - sizeof (kmutex_t) - sizeof (void *)];
};

/*
 * Total number of buckets will be NUM_BUCKETS + 1 .
 */

#pragma	align	64(vn_vfslocks_buckets)
static	struct vn_vfslocks_bucket	vn_vfslocks_buckets[NUM_BUCKETS + 1];

#define	VN_VFSLOCKS_SHIFT	9

#define	VN_VFSLOCKS_HASH(vfsvpptr)	\
	((((intptr_t)(vfsvpptr)) >> VN_VFSLOCKS_SHIFT) & NUM_BUCKETS)

/*
 * vn_vfslocks_getlock() uses an HASH scheme to generate
 * rwstlock using vfs/vnode pointer passed to it.
 *
 * vn_vfslocks_rele() releases a reference in the
 * HASH table which allows the entry allocated by
 * vn_vfslocks_getlock() to be freed at a later
 * stage when the refcount drops to zero.
 */

vn_vfslocks_entry_t *
vn_vfslocks_getlock(void *vfsvpptr)
{
	struct vn_vfslocks_bucket *bp;
	vn_vfslocks_entry_t *vep;
	vn_vfslocks_entry_t *tvep;

	ASSERT(vfsvpptr != NULL);
	bp = &vn_vfslocks_buckets[VN_VFSLOCKS_HASH(vfsvpptr)];

	mutex_enter(&bp->vb_lock);
	for (vep = bp->vb_list; vep != NULL; vep = vep->ve_next) {
		if (vep->ve_vpvfs == vfsvpptr) {
			vep->ve_refcnt++;
			mutex_exit(&bp->vb_lock);
			return (vep);
		}
	}
	mutex_exit(&bp->vb_lock);
	vep = kmem_alloc(sizeof (*vep), KM_SLEEP);
	rwst_init(&vep->ve_lock, NULL, RW_DEFAULT, NULL);
	vep->ve_vpvfs = (char *)vfsvpptr;
	vep->ve_refcnt = 1;
	mutex_enter(&bp->vb_lock);
	for (tvep = bp->vb_list; tvep != NULL; tvep = tvep->ve_next) {
		if (tvep->ve_vpvfs == vfsvpptr) {
			tvep->ve_refcnt++;
			mutex_exit(&bp->vb_lock);

			/*
			 * There is already an entry in the hash
			 * destroy what we just allocated.
			 */
			rwst_destroy(&vep->ve_lock);
			kmem_free(vep, sizeof (*vep));
			return (tvep);
		}
	}
	vep->ve_next = bp->vb_list;
	bp->vb_list = vep;
	mutex_exit(&bp->vb_lock);
	return (vep);
}

void
vn_vfslocks_rele(vn_vfslocks_entry_t *vepent)
{
	struct vn_vfslocks_bucket *bp;
	vn_vfslocks_entry_t *vep;
	vn_vfslocks_entry_t *pvep;

	ASSERT(vepent != NULL);
	ASSERT(vepent->ve_vpvfs != NULL);

	bp = &vn_vfslocks_buckets[VN_VFSLOCKS_HASH(vepent->ve_vpvfs)];

	mutex_enter(&bp->vb_lock);
	vepent->ve_refcnt--;

	if ((int32_t)vepent->ve_refcnt < 0)
		cmn_err(CE_PANIC, "vn_vfslocks_rele: refcount negative");

	if (vepent->ve_refcnt == 0) {
		for (vep = bp->vb_list; vep != NULL; vep = vep->ve_next) {
			if (vep->ve_vpvfs == vepent->ve_vpvfs) {
				if (bp->vb_list == vep)
					bp->vb_list = vep->ve_next;
				else {
					/* LINTED */
					pvep->ve_next = vep->ve_next;
				}
				mutex_exit(&bp->vb_lock);
				rwst_destroy(&vep->ve_lock);
				kmem_free(vep, sizeof (*vep));
				return;
			}
			pvep = vep;
		}
		cmn_err(CE_PANIC, "vn_vfslocks_rele: vp/vfs not found");
	}
	mutex_exit(&bp->vb_lock);
}

/*
 * vn_vfswlock_wait is used to implement a lock which is logically a writers
 * lock protecting the v_vfsmountedhere field.
 * vn_vfswlock_wait has been modified to be similar to vn_vfswlock,
 * except that it blocks to acquire the lock VVFSLOCK.
 *
 * traverse() and routines re-implementing part of traverse (e.g. autofs)
 * need to hold this lock. mount(), vn_rename(), vn_remove() and so on
 * need the non-blocking version of the writers lock i.e. vn_vfswlock
 */
int
vn_vfswlock_wait(vnode_t *vp)
{
	int retval;
	vn_vfslocks_entry_t *vpvfsentry;
	ASSERT(vp != NULL);

	vpvfsentry = vn_vfslocks_getlock(vp);
	retval = rwst_enter_sig(&vpvfsentry->ve_lock, RW_WRITER);

	if (retval == EINTR) {
		vn_vfslocks_rele(vpvfsentry);
		return (EINTR);
	}
	return (retval);
}

int
vn_vfsrlock_wait(vnode_t *vp)
{
	int retval;
	vn_vfslocks_entry_t *vpvfsentry;
	ASSERT(vp != NULL);

	vpvfsentry = vn_vfslocks_getlock(vp);
	retval = rwst_enter_sig(&vpvfsentry->ve_lock, RW_READER);

	if (retval == EINTR) {
		vn_vfslocks_rele(vpvfsentry);
		return (EINTR);
	}

	return (retval);
}


/*
 * vn_vfswlock is used to implement a lock which is logically a writers lock
 * protecting the v_vfsmountedhere field.
 */
int
vn_vfswlock(vnode_t *vp)
{
	vn_vfslocks_entry_t *vpvfsentry;

	/*
	 * If vp is NULL then somebody is trying to lock the covered vnode
	 * of /.  (vfs_vnodecovered is NULL for /).  This situation will
	 * only happen when unmounting /.  Since that operation will fail
	 * anyway, return EBUSY here instead of in VFS_UNMOUNT.
	 */
	if (vp == NULL)
		return (EBUSY);

	vpvfsentry = vn_vfslocks_getlock(vp);

	if (rwst_tryenter(&vpvfsentry->ve_lock, RW_WRITER))
		return (0);

	vn_vfslocks_rele(vpvfsentry);
	return (EBUSY);
}

int
vn_vfsrlock(vnode_t *vp)
{
	vn_vfslocks_entry_t *vpvfsentry;

	/*
	 * If vp is NULL then somebody is trying to lock the covered vnode
	 * of /.  (vfs_vnodecovered is NULL for /).  This situation will
	 * only happen when unmounting /.  Since that operation will fail
	 * anyway, return EBUSY here instead of in VFS_UNMOUNT.
	 */
	if (vp == NULL)
		return (EBUSY);

	vpvfsentry = vn_vfslocks_getlock(vp);

	if (rwst_tryenter(&vpvfsentry->ve_lock, RW_READER))
		return (0);

	vn_vfslocks_rele(vpvfsentry);
	return (EBUSY);
}

void
vn_vfsunlock(vnode_t *vp)
{
	vn_vfslocks_entry_t *vpvfsentry;

	/*
	 * ve_refcnt needs to be decremented twice.
	 * 1. To release refernce after a call to vn_vfslocks_getlock()
	 * 2. To release the reference from the locking routines like
	 *    vn_vfsrlock/vn_vfswlock etc,.
	 */
	vpvfsentry = vn_vfslocks_getlock(vp);
	vn_vfslocks_rele(vpvfsentry);

	rwst_exit(&vpvfsentry->ve_lock);
	vn_vfslocks_rele(vpvfsentry);
}

int
vn_vfswlock_held(vnode_t *vp)
{
	int held;
	vn_vfslocks_entry_t *vpvfsentry;

	ASSERT(vp != NULL);

	vpvfsentry = vn_vfslocks_getlock(vp);
	held = rwst_lock_held(&vpvfsentry->ve_lock, RW_WRITER);

	vn_vfslocks_rele(vpvfsentry);
	return (held);
}


int
vn_make_ops(
	const char *name,			/* Name of file system */
	const fs_operation_def_t *templ,	/* Operation specification */
	vnodeops_t **actual)			/* Return the vnodeops */
{
	int unused_ops;
	int error;

	*actual = (vnodeops_t *)kmem_alloc(sizeof (vnodeops_t), KM_SLEEP);

	(*actual)->vnop_name = name;

	error = fs_build_vector(*actual, &unused_ops, vn_ops_table, templ);
	if (error) {
		kmem_free(*actual, sizeof (vnodeops_t));
	}

#if DEBUG
	if (unused_ops != 0)
		cmn_err(CE_WARN, "vn_make_ops: %s: %d operations supplied "
		    "but not used", name, unused_ops);
#endif

	return (error);
}

/*
 * Free the vnodeops created as a result of vn_make_ops()
 */
void
vn_freevnodeops(vnodeops_t *vnops)
{
	kmem_free(vnops, sizeof (vnodeops_t));
}

/*
 * Vnode cache.
 */

/* ARGSUSED */
static int
vn_cache_constructor(void *buf, void *cdrarg, int kmflags)
{
	struct vnode *vp;

	vp = buf;

	mutex_init(&vp->v_lock, NULL, MUTEX_DEFAULT, NULL);
	cv_init(&vp->v_cv, NULL, CV_DEFAULT, NULL);
	rw_init(&vp->v_nbllock, NULL, RW_DEFAULT, NULL);
	rw_init(&vp->v_mslock, NULL, RW_DEFAULT, NULL);

	vp->v_femhead = NULL;	/* Must be done before vn_reinit() */
	vp->v_path = NULL;
	vp->v_mpssdata = NULL;

	return (0);
}

/* ARGSUSED */
static void
vn_cache_destructor(void *buf, void *cdrarg)
{
	struct vnode *vp;

	vp = buf;

	rw_destroy(&vp->v_mslock);
	rw_destroy(&vp->v_nbllock);
	cv_destroy(&vp->v_cv);
	mutex_destroy(&vp->v_lock);
}

void
vn_create_cache(void)
{
	vn_cache = kmem_cache_create("vn_cache", sizeof (struct vnode), 64,
	    vn_cache_constructor, vn_cache_destructor, NULL, NULL,
	    NULL, 0);
}

void
vn_destroy_cache(void)
{
	kmem_cache_destroy(vn_cache);
}

/*
 * Used by file systems when fs-specific nodes (e.g., ufs inodes) are
 * cached by the file system and vnodes remain associated.
 */
void
vn_recycle(vnode_t *vp)
{
	ASSERT(vp->v_pages == NULL);

	/*
	 * XXX - This really belongs in vn_reinit(), but we have some issues
	 * with the counts.  Best to have it here for clean initialization.
	 */
	vp->v_rdcnt = 0;
	vp->v_wrcnt = 0;
	vp->v_mmap_read = 0;
	vp->v_mmap_write = 0;

	/*
	 * If FEM was in use, make sure everything gets cleaned up
	 * NOTE: vp->v_femhead is initialized to NULL in the vnode
	 * constructor.
	 */
	if (vp->v_femhead) {
		/* XXX - There should be a free_femhead() that does all this */
		ASSERT(vp->v_femhead->femh_list == NULL);
		mutex_destroy(&vp->v_femhead->femh_lock);
		kmem_free(vp->v_femhead, sizeof (*(vp->v_femhead)));
		vp->v_femhead = NULL;
	}
	if (vp->v_path) {
		kmem_free(vp->v_path, strlen(vp->v_path) + 1);
		vp->v_path = NULL;
	}
	vp->v_mpssdata = NULL;
}

/*
 * Used to reset the vnode fields including those that are directly accessible
 * as well as those which require an accessor function.
 *
 * Does not initialize:
 *	synchronization objects: v_lock, v_nbllock, v_cv
 *	v_data (since FS-nodes and vnodes point to each other and should
 *		be updated simultaneously)
 *	v_op (in case someone needs to make a VOP call on this object)
 */
void
vn_reinit(vnode_t *vp)
{
	vp->v_count = 1;
	vp->v_vfsp = NULL;
	vp->v_stream = NULL;
	vp->v_vfsmountedhere = NULL;
	vp->v_flag = 0;
	vp->v_type = VNON;
	vp->v_rdev = NODEV;

	vp->v_filocks = NULL;
	vp->v_shrlocks = NULL;
	vp->v_pages = NULL;
	vp->v_npages = 0;
	vp->v_msnpages = 0;
	vp->v_scanfront = NULL;
	vp->v_scanback = NULL;

	vp->v_locality = NULL;
	vp->v_scantime = 0;
	vp->v_mset = 0;
	vp->v_msflags = 0;
	vp->v_msnext = NULL;
	vp->v_msprev = NULL;

	/* Handles v_femhead, v_path, and the r/w/map counts */
	vn_recycle(vp);
}

vnode_t *
vn_alloc(int kmflag)
{
	vnode_t *vp;

	vp = kmem_cache_alloc(vn_cache, kmflag);

	if (vp != NULL) {
		vp->v_femhead = NULL;	/* Must be done before vn_reinit() */
		vn_reinit(vp);
	}

	return (vp);
}

void
vn_free(vnode_t *vp)
{
	/*
	 * Some file systems call vn_free() with v_count of zero,
	 * some with v_count of 1.  In any case, the value should
	 * never be anything else.
	 */
	ASSERT((vp->v_count == 0) || (vp->v_count == 1));
	if (vp->v_path != NULL) {
		kmem_free(vp->v_path, strlen(vp->v_path) + 1);
		vp->v_path = NULL;
	}

	/* If FEM was in use, make sure everything gets cleaned up */
	if (vp->v_femhead) {
		/* XXX - There should be a free_femhead() that does all this */
		ASSERT(vp->v_femhead->femh_list == NULL);
		mutex_destroy(&vp->v_femhead->femh_lock);
		kmem_free(vp->v_femhead, sizeof (*(vp->v_femhead)));
		vp->v_femhead = NULL;
	}
	vp->v_mpssdata = NULL;
	kmem_cache_free(vn_cache, vp);
}

/*
 * vnode status changes, should define better states than 1, 0.
 */
void
vn_reclaim(vnode_t *vp)
{
	vfs_t   *vfsp = vp->v_vfsp;

	if (vfsp == NULL || vfsp->vfs_femhead == NULL) {
		return;
	}
	(void) VFS_VNSTATE(vfsp, vp, VNTRANS_RECLAIMED);
}

void
vn_idle(vnode_t *vp)
{
	vfs_t   *vfsp = vp->v_vfsp;

	if (vfsp == NULL || vfsp->vfs_femhead == NULL) {
		return;
	}
	(void) VFS_VNSTATE(vfsp, vp, VNTRANS_IDLED);
}
void
vn_exists(vnode_t *vp)
{
	vfs_t   *vfsp = vp->v_vfsp;

	if (vfsp == NULL || vfsp->vfs_femhead == NULL) {
		return;
	}
	(void) VFS_VNSTATE(vfsp, vp, VNTRANS_EXISTS);
}

void
vn_invalid(vnode_t *vp)
{
	vfs_t   *vfsp = vp->v_vfsp;

	if (vfsp == NULL || vfsp->vfs_femhead == NULL) {
		return;
	}
	(void) VFS_VNSTATE(vfsp, vp, VNTRANS_DESTROYED);
}

/* Vnode event notification */

int
vnevent_support(vnode_t *vp)
{
	if (vp == NULL)
		return (EINVAL);

	return (VOP_VNEVENT(vp, VE_SUPPORT));
}

void
vnevent_rename_src(vnode_t *vp)
{
	if (vp == NULL || vp->v_femhead == NULL) {
		return;
	}
	(void) VOP_VNEVENT(vp, VE_RENAME_SRC);
}

void
vnevent_rename_dest(vnode_t *vp)
{
	if (vp == NULL || vp->v_femhead == NULL) {
		return;
	}
	(void) VOP_VNEVENT(vp, VE_RENAME_DEST);
}

void
vnevent_remove(vnode_t *vp)
{
	if (vp == NULL || vp->v_femhead == NULL) {
		return;
	}
	(void) VOP_VNEVENT(vp, VE_REMOVE);
}

void
vnevent_rmdir(vnode_t *vp)
{
	if (vp == NULL || vp->v_femhead == NULL) {
		return;
	}
	(void) VOP_VNEVENT(vp, VE_RMDIR);
}

/*
 * Vnode accessors.
 */

int
vn_is_readonly(vnode_t *vp)
{
	return (vp->v_vfsp->vfs_flag & VFS_RDONLY);
}

int
vn_has_flocks(vnode_t *vp)
{
	return (vp->v_filocks != NULL);
}

int
vn_has_mandatory_locks(vnode_t *vp, int mode)
{
	return ((vp->v_filocks != NULL) && (MANDLOCK(vp, mode)));
}

int
vn_has_cached_data(vnode_t *vp)
{
	return (vp->v_pages != NULL);
}

/*
 * Return 0 if the vnode in question shouldn't be permitted into a zone via
 * zone_enter(2).
 */
int
vn_can_change_zones(vnode_t *vp)
{
	struct vfssw *vswp;
	int allow = 1;
	vnode_t *rvp;

	if (nfs_global_client_only != 0)
		return (1);

	/*
	 * We always want to look at the underlying vnode if there is one.
	 */
	if (VOP_REALVP(vp, &rvp) != 0)
		rvp = vp;
	/*
	 * Some pseudo filesystems (including doorfs) don't actually register
	 * their vfsops_t, so the following may return NULL; we happily let
	 * such vnodes switch zones.
	 */
	vswp = vfs_getvfsswbyvfsops(vfs_getops(rvp->v_vfsp));
	if (vswp != NULL) {
		if (vswp->vsw_flag & VSW_NOTZONESAFE)
			allow = 0;
		vfs_unrefvfssw(vswp);
	}
	return (allow);
}

/*
 * Return nonzero if the vnode is a mount point, zero if not.
 */
int
vn_ismntpt(vnode_t *vp)
{
	return (vp->v_vfsmountedhere != NULL);
}

/* Retrieve the vfs (if any) mounted on this vnode */
vfs_t *
vn_mountedvfs(vnode_t *vp)
{
	return (vp->v_vfsmountedhere);
}

/*
 * vn_is_opened() checks whether a particular file is opened and
 * whether the open is for read and/or write.
 *
 * Vnode counts are only kept on regular files (v_type=VREG).
 */
int
vn_is_opened(
	vnode_t *vp,
	v_mode_t mode)
{

	ASSERT(vp != NULL);

	switch (mode) {
	case V_WRITE:
		if (vp->v_wrcnt)
			return (V_TRUE);
		break;
	case V_RDANDWR:
		if (vp->v_rdcnt && vp->v_wrcnt)
			return (V_TRUE);
		break;
	case V_RDORWR:
		if (vp->v_rdcnt || vp->v_wrcnt)
			return (V_TRUE);
		break;
	case V_READ:
		if (vp->v_rdcnt)
			return (V_TRUE);
		break;
	}

	return (V_FALSE);
}

/*
 * vn_is_mapped() checks whether a particular file is mapped and whether
 * the file is mapped read and/or write.
 */
int
vn_is_mapped(
	vnode_t *vp,
	v_mode_t mode)
{

	ASSERT(vp != NULL);

#if !defined(_LP64)
	switch (mode) {
	/*
	 * The atomic_add_64_nv functions force atomicity in the
	 * case of 32 bit architectures. Otherwise the 64 bit values
	 * require two fetches. The value of the fields may be
	 * (potentially) changed between the first fetch and the
	 * second
	 */
	case V_WRITE:
		if (atomic_add_64_nv((&(vp->v_mmap_write)), 0))
			return (V_TRUE);
		break;
	case V_RDANDWR:
		if ((atomic_add_64_nv((&(vp->v_mmap_read)), 0)) &&
		    (atomic_add_64_nv((&(vp->v_mmap_write)), 0)))
			return (V_TRUE);
		break;
	case V_RDORWR:
		if ((atomic_add_64_nv((&(vp->v_mmap_read)), 0)) ||
		    (atomic_add_64_nv((&(vp->v_mmap_write)), 0)))
			return (V_TRUE);
		break;
	case V_READ:
		if (atomic_add_64_nv((&(vp->v_mmap_read)), 0))
			return (V_TRUE);
		break;
	}
#else
	switch (mode) {
	case V_WRITE:
		if (vp->v_mmap_write)
			return (V_TRUE);
		break;
	case V_RDANDWR:
		if (vp->v_mmap_read && vp->v_mmap_write)
			return (V_TRUE);
		break;
	case V_RDORWR:
		if (vp->v_mmap_read || vp->v_mmap_write)
			return (V_TRUE);
		break;
	case V_READ:
		if (vp->v_mmap_read)
			return (V_TRUE);
		break;
	}
#endif

	return (V_FALSE);
}

/*
 * Set the operations vector for a vnode.
 *
 * FEM ensures that the v_femhead pointer is filled in before the
 * v_op pointer is changed.  This means that if the v_femhead pointer
 * is NULL, and the v_op field hasn't changed since before which checked
 * the v_femhead pointer; then our update is ok - we are not racing with
 * FEM.
 */
void
vn_setops(vnode_t *vp, vnodeops_t *vnodeops)
{
	vnodeops_t	*op;

	ASSERT(vp != NULL);
	ASSERT(vnodeops != NULL);

	op = vp->v_op;
	membar_consumer();
	/*
	 * If vp->v_femhead == NULL, then we'll call casptr() to do the
	 * compare-and-swap on vp->v_op.  If either fails, then FEM is
	 * in effect on the vnode and we need to have FEM deal with it.
	 */
	if (vp->v_femhead != NULL || casptr(&vp->v_op, op, vnodeops) != op) {
		fem_setvnops(vp, vnodeops);
	}
}

/*
 * Retrieve the operations vector for a vnode
 * As with vn_setops(above); make sure we aren't racing with FEM.
 * FEM sets the v_op to a special, internal, vnodeops that wouldn't
 * make sense to the callers of this routine.
 */
vnodeops_t *
vn_getops(vnode_t *vp)
{
	vnodeops_t	*op;

	ASSERT(vp != NULL);

	op = vp->v_op;
	membar_consumer();
	if (vp->v_femhead == NULL && op == vp->v_op) {
		return (op);
	} else {
		return (fem_getvnops(vp));
	}
}

/*
 * Returns non-zero (1) if the vnodeops matches that of the vnode.
 * Returns zero (0) if not.
 */
int
vn_matchops(vnode_t *vp, vnodeops_t *vnodeops)
{
	return (vn_getops(vp) == vnodeops);
}

/*
 * Returns non-zero (1) if the specified operation matches the
 * corresponding operation for that the vnode.
 * Returns zero (0) if not.
 */

#define	MATCHNAME(n1, n2) (((n1)[0] == (n2)[0]) && (strcmp((n1), (n2)) == 0))

int
vn_matchopval(vnode_t *vp, char *vopname, fs_generic_func_p funcp)
{
	const fs_operation_trans_def_t *otdp;
	fs_generic_func_p *loc = NULL;
	vnodeops_t	*vop = vn_getops(vp);

	ASSERT(vopname != NULL);

	for (otdp = vn_ops_table; otdp->name != NULL; otdp++) {
		if (MATCHNAME(otdp->name, vopname)) {
			loc = (fs_generic_func_p *)((char *)(vop)
							+ otdp->offset);
			break;
		}
	}

	return ((loc != NULL) && (*loc == funcp));
}

/*
 * fs_new_caller_id() needs to return a unique ID on a given local system.
 * The IDs do not need to survive across reboots.  These are primarily
 * used so that (FEM) monitors can detect particular callers (such as
 * the NFS server) to a given vnode/vfs operation.
 */
u_longlong_t
fs_new_caller_id()
{
	static uint64_t next_caller_id = 0LL; /* First call returns 1 */

	return ((u_longlong_t)atomic_add_64_nv(&next_caller_id, 1));
}

/*
 * Given a starting vnode and a path, updates the path in the target vnode in
 * a safe manner.  If the vnode already has path information embedded, then the
 * cached path is left untouched.
 */
void
vn_setpath(vnode_t *rootvp, struct vnode *startvp, struct vnode *vp,
    const char *path, size_t plen)
{
	char	*rpath;
	vnode_t	*base;
	size_t	rpathlen, rpathalloc;
	int	doslash = 1;

	if (*path == '/') {
		base = rootvp;
		path++;
		plen--;
	} else {
		base = startvp;
	}

	/*
	 * We cannot grab base->v_lock while we hold vp->v_lock because of
	 * the potential for deadlock.
	 */
	mutex_enter(&base->v_lock);
	if (base->v_path == NULL) {
		mutex_exit(&base->v_lock);
		return;
	}

	rpathlen = strlen(base->v_path);
	rpathalloc = rpathlen + plen + 1;
	/* Avoid adding a slash if there's already one there */
	if (base->v_path[rpathlen-1] == '/')
		doslash = 0;
	else
		rpathalloc++;

	/*
	 * We don't want to call kmem_alloc(KM_SLEEP) with kernel locks held,
	 * so we must do this dance.  If, by chance, something changes the path,
	 * just give up since there is no real harm.
	 */
	mutex_exit(&base->v_lock);

	rpath = kmem_alloc(rpathalloc, KM_SLEEP);

	mutex_enter(&base->v_lock);
	if (base->v_path == NULL || strlen(base->v_path) != rpathlen) {
		mutex_exit(&base->v_lock);
		kmem_free(rpath, rpathalloc);
		return;
	}
	bcopy(base->v_path, rpath, rpathlen);
	mutex_exit(&base->v_lock);

	if (doslash)
		rpath[rpathlen++] = '/';
	bcopy(path, rpath + rpathlen, plen);
	rpath[rpathlen + plen] = '\0';

	mutex_enter(&vp->v_lock);
	if (vp->v_path != NULL) {
		mutex_exit(&vp->v_lock);
		kmem_free(rpath, rpathalloc);
	} else {
		vp->v_path = rpath;
		mutex_exit(&vp->v_lock);
	}
}

/*
 * Sets the path to the vnode to be the given string, regardless of current
 * context.  The string must be a complete path from rootdir.  This is only used
 * by fsop_root() for setting the path based on the mountpoint.
 */
void
vn_setpath_str(struct vnode *vp, const char *str, size_t len)
{
	char *buf = kmem_alloc(len + 1, KM_SLEEP);

	mutex_enter(&vp->v_lock);
	if (vp->v_path != NULL) {
		mutex_exit(&vp->v_lock);
		kmem_free(buf, len + 1);
		return;
	}

	vp->v_path = buf;
	bcopy(str, vp->v_path, len);
	vp->v_path[len] = '\0';

	mutex_exit(&vp->v_lock);
}

/*
 * Similar to vn_setpath_str(), this function sets the path of the destination
 * vnode to the be the same as the source vnode.
 */
void
vn_copypath(struct vnode *src, struct vnode *dst)
{
	char *buf;
	int alloc;

	mutex_enter(&src->v_lock);
	if (src->v_path == NULL) {
		mutex_exit(&src->v_lock);
		return;
	}
	alloc = strlen(src->v_path) + 1;

	/* avoid kmem_alloc() with lock held */
	mutex_exit(&src->v_lock);
	buf = kmem_alloc(alloc, KM_SLEEP);
	mutex_enter(&src->v_lock);
	if (src->v_path == NULL || strlen(src->v_path) + 1 != alloc) {
		mutex_exit(&src->v_lock);
		kmem_free(buf, alloc);
		return;
	}
	bcopy(src->v_path, buf, alloc);
	mutex_exit(&src->v_lock);

	mutex_enter(&dst->v_lock);
	if (dst->v_path != NULL) {
		mutex_exit(&dst->v_lock);
		kmem_free(buf, alloc);
		return;
	}
	dst->v_path = buf;
	mutex_exit(&dst->v_lock);
}

/*
 * XXX Private interface for segvn routines that handle vnode
 * large page segments.
 *
 * return 1 if vp's file system VOP_PAGEIO() implementation
 * can be safely used instead of VOP_GETPAGE() for handling
 * pagefaults against regular non swap files. VOP_PAGEIO()
 * interface is considered safe here if its implementation
 * is very close to VOP_GETPAGE() implementation.
 * e.g. It zero's out the part of the page beyond EOF. Doesn't
 * panic if there're file holes but instead returns an error.
 * Doesn't assume file won't be changed by user writes, etc.
 *
 * return 0 otherwise.
 *
 * For now allow segvn to only use VOP_PAGEIO() with ufs and nfs.
 */
int
vn_vmpss_usepageio(vnode_t *vp)
{
	vfs_t   *vfsp = vp->v_vfsp;
	char *fsname = vfssw[vfsp->vfs_fstype].vsw_name;
	char *pageio_ok_fss[] = {"ufs", "nfs", NULL};
	char **fsok = pageio_ok_fss;

	if (fsname == NULL) {
		return (0);
	}

	for (; *fsok; fsok++) {
		if (strcmp(*fsok, fsname) == 0) {
			return (1);
		}
	}
	return (0);
}

/* VOP_XXX() macros call the corresponding fop_xxx() function */

int
fop_open(
	vnode_t **vpp,
	int mode,
	cred_t *cr)
{
	int ret;
	vnode_t *vp = *vpp;

	VN_HOLD(vp);
	/*
	 * Adding to the vnode counts before calling open
	 * avoids the need for a mutex. It circumvents a race
	 * condition where a query made on the vnode counts results in a
	 * false negative. The inquirer goes away believing the file is
	 * not open when there is an open on the file already under way.
	 *
	 * The counts are meant to prevent NFS from granting a delegation
	 * when it would be dangerous to do so.
	 *
	 * The vnode counts are only kept on regular files
	 */
	if ((*vpp)->v_type == VREG) {
		if (mode & FREAD)
			atomic_add_32(&((*vpp)->v_rdcnt), 1);
		if (mode & FWRITE)
			atomic_add_32(&((*vpp)->v_wrcnt), 1);
	}

	ret = (*(*(vpp))->v_op->vop_open)(vpp, mode, cr);

	if (ret) {
		/*
		 * Use the saved vp just in case the vnode ptr got trashed
		 * by the error.
		 */
		if ((vp->v_type == VREG) && (mode & FREAD))
			atomic_add_32(&(vp->v_rdcnt), -1);
		if ((vp->v_type == VREG) && (mode & FWRITE))
			atomic_add_32(&(vp->v_wrcnt), -1);
	} else {
		/*
		 * Some filesystems will return a different vnode,
		 * but the same path was still used to open it.
		 * So if we do change the vnode and need to
		 * copy over the path, do so here, rather than special
		 * casing each filesystem. Adjust the vnode counts to
		 * reflect the vnode switch.
		 */

		if (*vpp != vp && *vpp != NULL) {
			vn_copypath(vp, *vpp);
			if (((*vpp)->v_type == VREG) && (mode & FREAD))
				atomic_add_32(&((*vpp)->v_rdcnt), 1);
			if ((vp->v_type == VREG) && (mode & FREAD))
				atomic_add_32(&(vp->v_rdcnt), -1);
			if (((*vpp)->v_type == VREG) && (mode & FWRITE))
				atomic_add_32(&((*vpp)->v_wrcnt), 1);
			if ((vp->v_type == VREG) && (mode & FWRITE))
				atomic_add_32(&(vp->v_wrcnt), -1);
		}
	}
	VN_RELE(vp);
	return (ret);
}

int
fop_close(
	vnode_t *vp,
	int flag,
	int count,
	offset_t offset,
	cred_t *cr)
{
	int error;
	error = (*(vp)->v_op->vop_close)(vp, flag, count, offset, cr);
	/*
	 * Check passed in count to handle possible dups. Vnode counts are only
	 * kept on regular files
	 */
	if ((vp->v_type == VREG) && (count == 1))  {
		if (flag & FREAD) {
			ASSERT(vp->v_rdcnt > 0);
			atomic_add_32(&(vp->v_rdcnt), -1);
		}
		if (flag & FWRITE) {
			ASSERT(vp->v_wrcnt > 0);
			atomic_add_32(&(vp->v_wrcnt), -1);
		}
	}
	return (error);
}

int
fop_read(
	vnode_t *vp,
	uio_t *uiop,
	int ioflag,
	cred_t *cr,
	struct caller_context *ct)
{
	return (*(vp)->v_op->vop_read)(vp, uiop, ioflag, cr, ct);
}

int
fop_write(
	vnode_t *vp,
	uio_t *uiop,
	int ioflag,
	cred_t *cr,
	struct caller_context *ct)
{
	return (*(vp)->v_op->vop_write)(vp, uiop, ioflag, cr, ct);
}

int
fop_ioctl(
	vnode_t *vp,
	int cmd,
	intptr_t arg,
	int flag,
	cred_t *cr,
	int *rvalp)
{
	return (*(vp)->v_op->vop_ioctl)(vp, cmd, arg, flag, cr, rvalp);
}

int
fop_setfl(
	vnode_t *vp,
	int oflags,
	int nflags,
	cred_t *cr)
{
	return (*(vp)->v_op->vop_setfl)(vp, oflags, nflags, cr);
}

int
fop_getattr(
	vnode_t *vp,
	vattr_t *vap,
	int flags,
	cred_t *cr)
{
	return (*(vp)->v_op->vop_getattr)(vp, vap, flags, cr);
}

int
fop_setattr(
	vnode_t *vp,
	vattr_t *vap,
	int flags,
	cred_t *cr,
	caller_context_t *ct)
{
	return (*(vp)->v_op->vop_setattr)(vp, vap, flags, cr, ct);
}

int
fop_access(
	vnode_t *vp,
	int mode,
	int flags,
	cred_t *cr)
{
	return (*(vp)->v_op->vop_access)(vp, mode, flags, cr);
}

int
fop_lookup(
	vnode_t *dvp,
	char *nm,
	vnode_t **vpp,
	pathname_t *pnp,
	int flags,
	vnode_t *rdir,
	cred_t *cr)
{
	int ret;

	ret = (*(dvp)->v_op->vop_lookup)(dvp, nm, vpp, pnp, flags, rdir, cr);
	if (ret == 0 && *vpp && (*vpp)->v_path == NULL)
		vn_setpath(rootdir, dvp, *vpp, nm, strlen(nm));

	return (ret);
}

int
fop_create(
	vnode_t *dvp,
	char *name,
	vattr_t *vap,
	vcexcl_t excl,
	int mode,
	vnode_t **vpp,
	cred_t *cr,
	int flag)
{
	int ret;

	ret = (*(dvp)->v_op->vop_create)
				(dvp, name, vap, excl, mode, vpp, cr, flag);
	if (ret == 0 && *vpp && (*vpp)->v_path == NULL)
		vn_setpath(rootdir, dvp, *vpp, name, strlen(name));

	return (ret);
}

int
fop_remove(
	vnode_t *dvp,
	char *nm,
	cred_t *cr)
{
	return (*(dvp)->v_op->vop_remove)(dvp, nm, cr);
}

int
fop_link(
	vnode_t *tdvp,
	vnode_t *svp,
	char *tnm,
	cred_t *cr)
{
	return (*(tdvp)->v_op->vop_link)(tdvp, svp, tnm, cr);
}

int
fop_rename(
	vnode_t *sdvp,
	char *snm,
	vnode_t *tdvp,
	char *tnm,
	cred_t *cr)
{
	return (*(sdvp)->v_op->vop_rename)(sdvp, snm, tdvp, tnm, cr);
}

int
fop_mkdir(
	vnode_t *dvp,
	char *dirname,
	vattr_t *vap,
	vnode_t **vpp,
	cred_t *cr)
{
	int ret;

	ret = (*(dvp)->v_op->vop_mkdir)(dvp, dirname, vap, vpp, cr);
	if (ret == 0 && *vpp && (*vpp)->v_path == NULL)
		vn_setpath(rootdir, dvp, *vpp, dirname, strlen(dirname));

	return (ret);
}

int
fop_rmdir(
	vnode_t *dvp,
	char *nm,
	vnode_t *cdir,
	cred_t *cr)
{
	return (*(dvp)->v_op->vop_rmdir)(dvp, nm, cdir, cr);
}

int
fop_readdir(
	vnode_t *vp,
	uio_t *uiop,
	cred_t *cr,
	int *eofp)
{
	return (*(vp)->v_op->vop_readdir)(vp, uiop, cr, eofp);
}

int
fop_symlink(
	vnode_t *dvp,
	char *linkname,
	vattr_t *vap,
	char *target,
	cred_t *cr)
{
	return (*(dvp)->v_op->vop_symlink) (dvp, linkname, vap, target, cr);
}

int
fop_readlink(
	vnode_t *vp,
	uio_t *uiop,
	cred_t *cr)
{
	return (*(vp)->v_op->vop_readlink)(vp, uiop, cr);
}

int
fop_fsync(
	vnode_t *vp,
	int syncflag,
	cred_t *cr)
{
	return (*(vp)->v_op->vop_fsync)(vp, syncflag, cr);
}

void
fop_inactive(
	vnode_t *vp,
	cred_t *cr)
{
	(*(vp)->v_op->vop_inactive)(vp, cr);
}

int
fop_fid(
	vnode_t *vp,
	fid_t *fidp)
{
	return (*(vp)->v_op->vop_fid)(vp, fidp);
}

int
fop_rwlock(
	vnode_t *vp,
	int write_lock,
	caller_context_t *ct)
{
	return ((*(vp)->v_op->vop_rwlock)(vp, write_lock, ct));
}

void
fop_rwunlock(
	vnode_t *vp,
	int write_lock,
	caller_context_t *ct)
{
	(*(vp)->v_op->vop_rwunlock)(vp, write_lock, ct);
}

int
fop_seek(
	vnode_t *vp,
	offset_t ooff,
	offset_t *noffp)
{
	return (*(vp)->v_op->vop_seek)(vp, ooff, noffp);
}

int
fop_cmp(
	vnode_t *vp1,
	vnode_t *vp2)
{
	return (*(vp1)->v_op->vop_cmp)(vp1, vp2);
}

int
fop_frlock(
	vnode_t *vp,
	int cmd,
	flock64_t *bfp,
	int flag,
	offset_t offset,
	struct flk_callback *flk_cbp,
	cred_t *cr)
{
	return (*(vp)->v_op->vop_frlock)
				(vp, cmd, bfp, flag, offset, flk_cbp, cr);
}

int
fop_space(
	vnode_t *vp,
	int cmd,
	flock64_t *bfp,
	int flag,
	offset_t offset,
	cred_t *cr,
	caller_context_t *ct)
{
	return (*(vp)->v_op->vop_space)(vp, cmd, bfp, flag, offset, cr, ct);
}

int
fop_realvp(
	vnode_t *vp,
	vnode_t **vpp)
{
	return (*(vp)->v_op->vop_realvp)(vp, vpp);
}

int
fop_getpage(
	vnode_t *vp,
	offset_t off,
	size_t len,
	uint_t *protp,
	page_t **plarr,
	size_t plsz,
	struct seg *seg,
	caddr_t addr,
	enum seg_rw rw,
	cred_t *cr)
{
	return (*(vp)->v_op->vop_getpage)
			(vp, off, len, protp, plarr, plsz, seg, addr, rw, cr);
}

int
fop_putpage(
	vnode_t *vp,
	offset_t off,
	size_t len,
	int flags,
	cred_t *cr)
{
	return (*(vp)->v_op->vop_putpage)(vp, off, len, flags, cr);
}

int
fop_map(
	vnode_t *vp,
	offset_t off,
	struct as *as,
	caddr_t *addrp,
	size_t len,
	uchar_t prot,
	uchar_t maxprot,
	uint_t flags,
	cred_t *cr)
{
	return (*(vp)->v_op->vop_map)
			(vp, off, as, addrp, len, prot, maxprot, flags, cr);
}

int
fop_addmap(
	vnode_t *vp,
	offset_t off,
	struct as *as,
	caddr_t addr,
	size_t len,
	uchar_t prot,
	uchar_t maxprot,
	uint_t flags,
	cred_t *cr)
{
	int error;
	u_longlong_t delta;

	error = (*(vp)->v_op->vop_addmap)
			(vp, off, as, addr, len, prot, maxprot, flags, cr);

	if ((!error) && (vp->v_type == VREG)) {
		delta = (u_longlong_t)btopr(len);
		/*
		 * If file is declared MAP_PRIVATE, it can't be written back
		 * even if open for write. Handle as read.
		 */
		if (flags & MAP_PRIVATE) {
			atomic_add_64((uint64_t *)(&(vp->v_mmap_read)),
				(int64_t)delta);
		} else {
			/*
			 * atomic_add_64 forces the fetch of a 64 bit value to
			 * be atomic on 32 bit machines
			 */
			if (maxprot & PROT_WRITE)
				atomic_add_64((uint64_t *)(&(vp->v_mmap_write)),
					(int64_t)delta);
			if (maxprot & PROT_READ)
				atomic_add_64((uint64_t *)(&(vp->v_mmap_read)),
					(int64_t)delta);
			if (maxprot & PROT_EXEC)
				atomic_add_64((uint64_t *)(&(vp->v_mmap_read)),
					(int64_t)delta);
		}
	}
	return (error);
}

int
fop_delmap(
	vnode_t *vp,
	offset_t off,
	struct as *as,
	caddr_t addr,
	size_t len,
	uint_t prot,
	uint_t maxprot,
	uint_t flags,
	cred_t *cr)
{
	int error;
	u_longlong_t delta;
	error = (*(vp)->v_op->vop_delmap)
		(vp, off, as, addr, len, prot, maxprot, flags, cr);

	/*
	 * NFS calls into delmap twice, the first time
	 * it simply establishes a callback mechanism and returns EAGAIN
	 * while the real work is being done upon the second invocation.
	 * We have to detect this here and only decrement the counts upon
	 * the second delmap request.
	 */
	if ((error != EAGAIN) && (vp->v_type == VREG)) {

		delta = (u_longlong_t)btopr(len);

		if (flags & MAP_PRIVATE) {
			atomic_add_64((uint64_t *)(&(vp->v_mmap_read)),
				(int64_t)(-delta));
		} else {
			/*
			 * atomic_add_64 forces the fetch of a 64 bit value
			 * to be atomic on 32 bit machines
			 */
			if (maxprot & PROT_WRITE)
				atomic_add_64((uint64_t *)(&(vp->v_mmap_write)),
					(int64_t)(-delta));
			if (maxprot & PROT_READ)
				atomic_add_64((uint64_t *)(&(vp->v_mmap_read)),
					(int64_t)(-delta));
			if (maxprot & PROT_EXEC)
				atomic_add_64((uint64_t *)(&(vp->v_mmap_read)),
					(int64_t)(-delta));
		}
	}
	return (error);
}


int
fop_poll(
	vnode_t *vp,
	short events,
	int anyyet,
	short *reventsp,
	struct pollhead **phpp)
{
	return (*(vp)->v_op->vop_poll)(vp, events, anyyet, reventsp, phpp);
}

int
fop_dump(
	vnode_t *vp,
	caddr_t addr,
	int lbdn,
	int dblks)
{
	return (*(vp)->v_op->vop_dump)(vp, addr, lbdn, dblks);
}

int
fop_pathconf(
	vnode_t *vp,
	int cmd,
	ulong_t *valp,
	cred_t *cr)
{
	return (*(vp)->v_op->vop_pathconf)(vp, cmd, valp, cr);
}

int
fop_pageio(
	vnode_t *vp,
	struct page *pp,
	u_offset_t io_off,
	size_t io_len,
	int flags,
	cred_t *cr)
{
	return (*(vp)->v_op->vop_pageio)(vp, pp, io_off, io_len, flags, cr);
}

int
fop_dumpctl(
	vnode_t *vp,
	int action,
	int *blkp)
{
	return (*(vp)->v_op->vop_dumpctl)(vp, action, blkp);
}

void
fop_dispose(
	vnode_t *vp,
	page_t *pp,
	int flag,
	int dn,
	cred_t *cr)
{
	(*(vp)->v_op->vop_dispose)(vp, pp, flag, dn, cr);
}

int
fop_setsecattr(
	vnode_t *vp,
	vsecattr_t *vsap,
	int flag,
	cred_t *cr)
{
	return (*(vp)->v_op->vop_setsecattr) (vp, vsap, flag, cr);
}

int
fop_getsecattr(
	vnode_t *vp,
	vsecattr_t *vsap,
	int flag,
	cred_t *cr)
{
	return (*(vp)->v_op->vop_getsecattr) (vp, vsap, flag, cr);
}

int
fop_shrlock(
	vnode_t *vp,
	int cmd,
	struct shrlock *shr,
	int flag,
	cred_t *cr)
{
	return (*(vp)->v_op->vop_shrlock)(vp, cmd, shr, flag, cr);
}

int
fop_vnevent(vnode_t *vp, vnevent_t vnevent)
{
	return (*(vp)->v_op->vop_vnevent)(vp, vnevent);
}