xnu-1699.22.73.tar.gz

[apple/xnu.git] / bsd / kern / kern_descrip.c

/*
 * Copyright (c) 2000-2010 Apple Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 * 
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */
/* Copyright (c) 1995, 1997 Apple Computer, Inc. All Rights Reserved */
/*
 * Copyright (c) 1982, 1986, 1989, 1991, 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.
 *
 *      @(#)kern_descrip.c      8.8 (Berkeley) 2/14/95
 */
/*
 * NOTICE: This file was modified by SPARTA, Inc. in 2006 to introduce
 * support for mandatory and extensible security protections.  This notice
 * is included in support of clause 2.2 (b) of the Apple Public License,
 * Version 2.0.
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/filedesc.h>
#include <sys/kernel.h>
#include <sys/vnode_internal.h>
#include <sys/proc_internal.h>
#include <sys/kauth.h>
#include <sys/file_internal.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <sys/fcntl.h>
#include <sys/malloc.h>
#include <sys/mman.h>
#include <sys/syslog.h>
#include <sys/unistd.h>
#include <sys/resourcevar.h>
#include <sys/aio_kern.h>
#include <sys/ev.h>
#include <kern/lock.h>
#include <sys/uio_internal.h>

#include <security/audit/audit.h>

#include <sys/mount_internal.h>
#include <sys/kdebug.h>
#include <sys/sysproto.h>
#include <sys/pipe.h>
#include <sys/spawn.h>
#include <kern/kern_types.h>
#include <kern/kalloc.h>
#include <libkern/OSAtomic.h>

#include <sys/ubc_internal.h>

#include <kern/ipc_misc.h>
#include <vm/vm_protos.h>

#include <mach/mach_port.h>

#if CONFIG_PROTECT
#include <sys/cprotect.h>
#endif
#include <hfs/hfs.h>

kern_return_t ipc_object_copyin(ipc_space_t, mach_port_name_t,
    mach_msg_type_name_t, ipc_port_t *);
void ipc_port_release_send(ipc_port_t);

struct psemnode;
struct pshmnode;

static int finishdup(proc_t p,
    struct filedesc *fdp, int old, int new, int flags, int32_t *retval);

int falloc_locked(proc_t p, struct fileproc **resultfp, int *resultfd, vfs_context_t ctx, int locked);
void fg_drop(struct fileproc * fp);
void fg_free(struct fileglob *fg);
void fg_ref(struct fileproc * fp);
void fileport_releasefg(struct fileglob *fg);

/* flags for close_internal_locked */
#define FD_DUP2RESV 1
static int close_internal_locked(struct proc *p, int fd, struct fileproc *fp, int flags);

static int closef_finish(struct fileproc *fp, struct fileglob *fg, proc_t p, vfs_context_t ctx);

/* We don't want these exported */
__private_extern__
int open1(vfs_context_t, struct nameidata *, int, struct vnode_attr *, int32_t *);

__private_extern__
int unlink1(vfs_context_t, struct nameidata *, int);

static void _fdrelse(struct proc * p, int fd);


extern void file_lock_init(void) __attribute__((section("__TEXT, initcode")));
extern int kqueue_stat(struct fileproc *fp, void *ub, int isstat4, proc_t p);
#if SOCKETS
extern int soo_stat(struct socket *so, void *ub, int isstat64);
#endif /* SOCKETS */

extern kauth_scope_t    kauth_scope_fileop;

extern int cs_debug;

/* Conflict wait queue for when selects collide (opaque type) */
extern struct wait_queue select_conflict_queue;

#define f_flag f_fglob->fg_flag
#define f_type f_fglob->fg_type
#define f_msgcount f_fglob->fg_msgcount
#define f_cred f_fglob->fg_cred
#define f_ops f_fglob->fg_ops
#define f_offset f_fglob->fg_offset
#define f_data f_fglob->fg_data
/*
 * Descriptor management.
 */
struct filelist filehead;       /* head of list of open files */
struct fmsglist fmsghead;       /* head of list of open files */
struct fmsglist fmsg_ithead;    /* head of list of open files */
int nfiles;                     /* actual number of open files */


lck_grp_attr_t * file_lck_grp_attr;
lck_grp_t * file_lck_grp;
lck_attr_t * file_lck_attr;

lck_mtx_t * uipc_lock;
lck_mtx_t * file_flist_lock;


/*
 * file_lock_init
 *
 * Description: Initialize the file lock group and the uipc and flist locks
 *
 * Parameters:  (void)
 *
 * Returns:     void
 *
 * Notes:       Called at system startup from bsd_init().
 */
void
file_lock_init(void)
{
        /* allocate file lock group attribute and group */
        file_lck_grp_attr= lck_grp_attr_alloc_init();

        file_lck_grp = lck_grp_alloc_init("file",  file_lck_grp_attr);

        /* Allocate file lock attribute */
        file_lck_attr = lck_attr_alloc_init();

        uipc_lock = lck_mtx_alloc_init(file_lck_grp, file_lck_attr);
        file_flist_lock = lck_mtx_alloc_init(file_lck_grp, file_lck_attr);
}


/*
 * proc_fdlock, proc_fdlock_spin
 *
 * Description: Lock to control access to the per process struct fileproc
 *              and struct filedesc
 *
 * Parameters:  p                               Process to take the lock on
 *
 * Returns:     void
 *
 * Notes:       The lock is initialized in forkproc() and destroyed in
 *              reap_child_process().
 */
void
proc_fdlock(proc_t p)
{
        lck_mtx_lock(&p->p_fdmlock);
}

void
proc_fdlock_spin(proc_t p)
{
        lck_mtx_lock_spin(&p->p_fdmlock);
}

void
proc_fdlock_assert(proc_t p, int assertflags)
{
        lck_mtx_assert(&p->p_fdmlock, assertflags);
}


/*
 * proc_fdunlock
 *
 * Description: Unlock the lock previously locked by a call to proc_fdlock()
 *
 * Parameters:  p                               Process to drop the lock on
 *
 * Returns:     void
 */
void
proc_fdunlock(proc_t p)
{
        lck_mtx_unlock(&p->p_fdmlock);
}


/*
 * System calls on descriptors.
 */


/*
 * getdtablesize
 *
 * Description: Returns the per process maximum size of the descriptor table
 *
 * Parameters:  p                               Process being queried
 *              retval                          Pointer to the call return area
 *
 * Returns:     0                               Success
 *
 * Implicit returns:
 *              *retval (modified)              Size of dtable
 */
int
getdtablesize(proc_t p, __unused struct getdtablesize_args *uap, int32_t *retval)
{
        proc_fdlock_spin(p);
        *retval = min((int)p->p_rlimit[RLIMIT_NOFILE].rlim_cur, maxfiles);
        proc_fdunlock(p);

        return (0);
}


void
procfdtbl_reservefd(struct proc * p, int fd)
{
        p->p_fd->fd_ofiles[fd] = NULL;
        p->p_fd->fd_ofileflags[fd] |= UF_RESERVED;
}

void
procfdtbl_markclosefd(struct proc * p, int fd)
{
        p->p_fd->fd_ofileflags[fd] |= (UF_RESERVED | UF_CLOSING);
}

void
procfdtbl_releasefd(struct proc * p, int fd, struct fileproc * fp)
{
        if (fp != NULL)
                p->p_fd->fd_ofiles[fd] = fp;
        p->p_fd->fd_ofileflags[fd] &= ~UF_RESERVED;
        if ((p->p_fd->fd_ofileflags[fd] & UF_RESVWAIT) == UF_RESVWAIT) {
                p->p_fd->fd_ofileflags[fd] &= ~UF_RESVWAIT;
                wakeup(&p->p_fd);
        }
}

void 
procfdtbl_waitfd(struct proc * p, int fd)
{
        p->p_fd->fd_ofileflags[fd] |= UF_RESVWAIT;
        msleep(&p->p_fd, &p->p_fdmlock, PRIBIO, "ftbl_waitfd", NULL);
}


void
procfdtbl_clearfd(struct proc * p, int fd)
{
        int waiting;

        waiting = (p->p_fd->fd_ofileflags[fd] & UF_RESVWAIT);
        p->p_fd->fd_ofiles[fd] = NULL;       
        p->p_fd->fd_ofileflags[fd] = 0;
        if ( waiting == UF_RESVWAIT) {
                wakeup(&p->p_fd);
        }
}

/*
 * _fdrelse
 *
 * Description: Inline utility function to free an fd in a filedesc
 *
 * Parameters:  fdp                             Pointer to filedesc fd lies in
 *              fd                              fd to free
 *              reserv                          fd should be reserved
 *
 * Returns:     void
 *
 * Locks:       Assumes proc_fdlock for process pointing to fdp is held by
 *              the caller
 */
static void
_fdrelse(struct proc * p, int fd)
{
        struct filedesc *fdp = p->p_fd;
        int nfd = 0;

        if (fd < fdp->fd_freefile)
                fdp->fd_freefile = fd;
#if DIAGNOSTIC
        if (fd > fdp->fd_lastfile)
                panic("fdrelse: fd_lastfile inconsistent");
#endif
        procfdtbl_clearfd(p, fd);

        while ((nfd = fdp->fd_lastfile) > 0 &&
                        fdp->fd_ofiles[nfd] == NULL &&
                        !(fdp->fd_ofileflags[nfd] & UF_RESERVED))
                fdp->fd_lastfile--;
}


int
fd_rdwr(
        int fd,
        enum uio_rw rw,
        uint64_t base,
        int64_t len,
        enum uio_seg segflg,
        off_t   offset,
        int     io_flg,
        int64_t *aresid)
{
        struct fileproc *fp;
        proc_t  p;
        int error = 0;
        int flags = 0;
        int spacetype;
        uio_t auio = NULL;
        char uio_buf[ UIO_SIZEOF(1) ];
        struct vfs_context context = *(vfs_context_current());

        p = current_proc();

        error = fp_lookup(p, fd, &fp, 0);
        if (error)
                return(error);

        if (fp->f_type != DTYPE_VNODE && fp->f_type != DTYPE_PIPE && fp->f_type != DTYPE_SOCKET) {
                error = EINVAL;
                goto out;
        }
        if (rw == UIO_WRITE && !(fp->f_flag & FWRITE)) {
                error = EBADF;
                goto out;
        }
        
        if (rw == UIO_READ && !(fp->f_flag & FREAD)) {
                error = EBADF;
                goto out;
        }
        
        context.vc_ucred = fp->f_fglob->fg_cred;

        if (UIO_SEG_IS_USER_SPACE(segflg))
                spacetype = proc_is64bit(p) ? UIO_USERSPACE64 : UIO_USERSPACE32;
        else
                spacetype = UIO_SYSSPACE;

        auio = uio_createwithbuffer(1, offset, spacetype, rw, &uio_buf[0], sizeof(uio_buf));

        uio_addiov(auio, base, len);

        if ( !(io_flg & IO_APPEND))
                flags = FOF_OFFSET;

        if (rw == UIO_WRITE)
                error = fo_write(fp, auio, flags, &context);
        else
                error = fo_read(fp, auio, flags, &context);

        if (aresid)
                *aresid = uio_resid(auio);
        else {
                if (uio_resid(auio) && error == 0)
                        error = EIO;
        }
out:
        if (rw == UIO_WRITE && error == 0)
                fp_drop_written(p, fd, fp);
        else
                fp_drop(p, fd, fp, 0);

        return error;
}



/*
 * dup
 *
 * Description: Duplicate a file descriptor.
 *
 * Parameters:  p                               Process performing the dup
 *              uap->fd                         The fd to dup
 *              retval                          Pointer to the call return area
 *
 * Returns:     0                               Success
 *              !0                              Errno
 *
 * Implicit returns:
 *              *retval (modified)              The new descriptor
 */
int
dup(proc_t p, struct dup_args *uap, int32_t *retval)
{
        struct filedesc *fdp = p->p_fd;
        int old = uap->fd;
        int new, error;
        struct fileproc *fp;

        proc_fdlock(p);
        if ( (error = fp_lookup(p, old, &fp, 1)) ) {
                proc_fdunlock(p);
                return(error);
        }
        if ( (error = fdalloc(p, 0, &new)) ) {
                fp_drop(p, old, fp, 1);
                proc_fdunlock(p);
                return (error);
        }
        error = finishdup(p, fdp, old, new, 0, retval);
        fp_drop(p, old, fp, 1);
        proc_fdunlock(p);

        return (error);
}

/*
 * dup2
 *
 * Description: Duplicate a file descriptor to a particular value.
 *
 * Parameters:  p                               Process performing the dup
 *              uap->from                       The fd to dup
 *              uap->to                         The fd to dup it to
 *              retval                          Pointer to the call return area
 *
 * Returns:     0                               Success
 *              !0                              Errno
 *
 * Implicit returns:
 *              *retval (modified)              The new descriptor
 */
int
dup2(proc_t p, struct dup2_args *uap, int32_t *retval)
{
        struct filedesc *fdp = p->p_fd;
        int old = uap->from, new = uap->to;
        int i, error;
        struct fileproc *fp, *nfp;

        proc_fdlock(p);

startover:
        if ( (error = fp_lookup(p, old, &fp, 1)) ) {
                proc_fdunlock(p);
                return(error);
        }
        if (new < 0 ||
                (rlim_t)new >= p->p_rlimit[RLIMIT_NOFILE].rlim_cur ||
            new >= maxfiles) {
                fp_drop(p, old, fp, 1);
                proc_fdunlock(p);
                return (EBADF);
        }
        if (old == new) {
                fp_drop(p, old, fp, 1);
                *retval = new;
                proc_fdunlock(p);
                return (0);
        }
        if (new < 0 || new >= fdp->fd_nfiles) {
                if ( (error = fdalloc(p, new, &i)) ) {
                        fp_drop(p, old, fp, 1);
                        proc_fdunlock(p);
                        return (error);
                }
                if (new != i) {
                        fdrelse(p, i);
                        goto closeit;
                }
        } else {
closeit:
                while ((fdp->fd_ofileflags[new] & UF_RESERVED) == UF_RESERVED)  {
                                fp_drop(p, old, fp, 1);
                                procfdtbl_waitfd(p, new);
#if DIAGNOSTIC
                                proc_fdlock_assert(p, LCK_MTX_ASSERT_OWNED);
#endif
                                goto startover;
                }

                if ((fdp->fd_ofiles[new] != NULL) &&
                    ((error = fp_lookup(p, new, &nfp, 1)) == 0)) {
                        fp_drop(p, old, fp, 1);
                        (void)close_internal_locked(p, new, nfp, FD_DUP2RESV);
#if DIAGNOSTIC
                        proc_fdlock_assert(p, LCK_MTX_ASSERT_OWNED);
#endif
                        procfdtbl_clearfd(p, new);
                        goto startover;
                } else  {
#if DIAGNOSTIC
                        if (fdp->fd_ofiles[new] != NULL)
                                panic("dup2: no ref on fileproc %d", new);
#endif
                        procfdtbl_reservefd(p, new);
                }

#if DIAGNOSTIC
                proc_fdlock_assert(p, LCK_MTX_ASSERT_OWNED);
#endif

        }
#if DIAGNOSTIC
        if (fdp->fd_ofiles[new] != 0)
                panic("dup2: overwriting fd_ofiles with new %d", new);
        if ((fdp->fd_ofileflags[new] & UF_RESERVED) == 0)
                panic("dup2: unreserved fileflags with new %d", new);
#endif
        error = finishdup(p, fdp, old, new, 0, retval);
        fp_drop(p, old, fp, 1);
        proc_fdunlock(p);

        return(error);
}


/*
 * fcntl
 *
 * Description: The file control system call.
 *
 * Parameters:  p                               Process performing the fcntl
 *              uap->fd                         The fd to operate against
 *              uap->cmd                        The command to perform
 *              uap->arg                        Pointer to the command argument
 *              retval                          Pointer to the call return area
 *
 * Returns:     0                               Success
 *              !0                              Errno (see fcntl_nocancel)
 *
 * Implicit returns:
 *              *retval (modified)              fcntl return value (if any)
 *
 * Notes:       This system call differs from fcntl_nocancel() in that it
 *              tests for cancellation prior to performing a potentially
 *              blocking operation.
 */
int
fcntl(proc_t p, struct fcntl_args *uap, int32_t *retval)
{
        __pthread_testcancel(1);
        return(fcntl_nocancel(p, (struct fcntl_nocancel_args *)uap, retval));
}


/*
 * fcntl_nocancel
 *
 * Description: A non-cancel-testing file control system call.
 *
 * Parameters:  p                               Process performing the fcntl
 *              uap->fd                         The fd to operate against
 *              uap->cmd                        The command to perform
 *              uap->arg                        Pointer to the command argument
 *              retval                          Pointer to the call return area
 *
 * Returns:     0                               Success
 *              EINVAL
 *      fp_lookup:EBADF                         Bad file descriptor
 * [F_DUPFD]
 *      fdalloc:EMFILE
 *      fdalloc:ENOMEM
 *      finishdup:EBADF
 *      finishdup:ENOMEM
 * [F_SETOWN]
 *              ESRCH
 * [F_SETLK]
 *              EBADF
 *              EOVERFLOW
 *      copyin:EFAULT
 *      vnode_getwithref:???
 *      VNOP_ADVLOCK:???
 * [F_GETLK]
 *              EBADF
 *              EOVERFLOW
 *      copyin:EFAULT
 *      copyout:EFAULT
 *      vnode_getwithref:???
 *      VNOP_ADVLOCK:???
 * [F_PREALLOCATE]
 *              EBADF
 *              EINVAL
 *      copyin:EFAULT
 *      copyout:EFAULT
 *      vnode_getwithref:???
 *      VNOP_ALLOCATE:???
 * [F_SETSIZE,F_RDADVISE]
 *              EBADF
 *      copyin:EFAULT
 *      vnode_getwithref:???
 * [F_RDAHEAD,F_NOCACHE]
 *              EBADF
 *      vnode_getwithref:???
 * [???]
 *
 * Implicit returns:
 *              *retval (modified)              fcntl return value (if any)
 */
int
fcntl_nocancel(proc_t p, struct fcntl_nocancel_args *uap, int32_t *retval)
{
        int fd = uap->fd;
        struct filedesc *fdp = p->p_fd;
        struct fileproc *fp;
        char *pop;
        struct vnode *vp = NULLVP;      /* for AUDIT_ARG() at end */
        int i, tmp, error, error2, flg = F_POSIX;
        struct flock fl;
        struct vfs_context context;
        off_t offset;
        int newmin;
        daddr64_t lbn, bn;
        unsigned int fflag;
        user_addr_t argp;
        boolean_t is64bit;

        AUDIT_ARG(fd, uap->fd);
        AUDIT_ARG(cmd, uap->cmd);

        proc_fdlock(p);
        if ( (error = fp_lookup(p, fd, &fp, 1)) ) {
                proc_fdunlock(p);
                return(error);
        }
        context.vc_thread = current_thread();
        context.vc_ucred = fp->f_cred;

        is64bit = proc_is64bit(p);
        if (is64bit) {
                argp = uap->arg;
        }
        else {
                /*
                 * Since the arg parameter is defined as a long but may be
                 * either a long or a pointer we must take care to handle
                 * sign extension issues.  Our sys call munger will sign
                 * extend a long when we are called from a 32-bit process.
                 * Since we can never have an address greater than 32-bits
                 * from a 32-bit process we lop off the top 32-bits to avoid
                 * getting the wrong address
                 */
                argp = CAST_USER_ADDR_T((uint32_t)uap->arg);
        }

        pop = &fdp->fd_ofileflags[fd];

#if CONFIG_MACF
        error = mac_file_check_fcntl(proc_ucred(p), fp->f_fglob, uap->cmd,
            uap->arg);
        if (error)
                goto out;
#endif

        switch (uap->cmd) {

        case F_DUPFD:
        case F_DUPFD_CLOEXEC:
                newmin = CAST_DOWN_EXPLICIT(int, uap->arg); /* arg is an int, so we won't lose bits */
                AUDIT_ARG(value32, newmin);
                if ((u_int)newmin >= p->p_rlimit[RLIMIT_NOFILE].rlim_cur ||
                    newmin >= maxfiles) {
                        error = EINVAL;
                        goto out;
                }
                if ( (error = fdalloc(p, newmin, &i)) )
                        goto out;
                error = finishdup(p, fdp, fd, i,
                    uap->cmd == F_DUPFD_CLOEXEC ? UF_EXCLOSE : 0, retval);
                goto out;

        case F_GETFD:
                *retval = (*pop & UF_EXCLOSE)? 1 : 0;
                error = 0;
                goto out;

        case F_SETFD:
                AUDIT_ARG(value32, uap->arg);
                *pop = (*pop &~ UF_EXCLOSE) |
                        (uap->arg & 1)? UF_EXCLOSE : 0;
                error = 0;
                goto out;

        case F_GETFL:
                *retval = OFLAGS(fp->f_flag);
                error = 0;
                goto out;

        case F_SETFL:
                fp->f_flag &= ~FCNTLFLAGS;
                tmp = CAST_DOWN_EXPLICIT(int, uap->arg); /* arg is an int, so we won't lose bits */
                AUDIT_ARG(value32, tmp);
                fp->f_flag |= FFLAGS(tmp) & FCNTLFLAGS;
                tmp = fp->f_flag & FNONBLOCK;
                error = fo_ioctl(fp, FIONBIO, (caddr_t)&tmp, &context);
                if (error)
                        goto out;
                tmp = fp->f_flag & FASYNC;
                error = fo_ioctl(fp, FIOASYNC, (caddr_t)&tmp, &context);
                if (!error)
                        goto out;
                fp->f_flag &= ~FNONBLOCK;
                tmp = 0;
                (void)fo_ioctl(fp, FIONBIO, (caddr_t)&tmp, &context);
                goto out;

        case F_GETOWN:
                if (fp->f_type == DTYPE_SOCKET) {
                        *retval = ((struct socket *)fp->f_data)->so_pgid;
                        error = 0;
                        goto out;
                }
                error = fo_ioctl(fp, (int)TIOCGPGRP, (caddr_t)retval, &context);
                *retval = -*retval;
                goto out;

        case F_SETOWN:
                tmp = CAST_DOWN_EXPLICIT(pid_t, uap->arg); /* arg is an int, so we won't lose bits */
                AUDIT_ARG(value32, tmp);
                if (fp->f_type == DTYPE_SOCKET) {
                        ((struct socket *)fp->f_data)->so_pgid = tmp;
                        error =0;
                        goto out;
                }
                if (fp->f_type == DTYPE_PIPE) {
                        error =  fo_ioctl(fp, TIOCSPGRP, (caddr_t)&tmp, &context);
                        goto out;
                }

                if (tmp <= 0) {
                        tmp = -tmp;
                } else {
                        proc_t p1 = proc_find(tmp);
                        if (p1 == 0) {
                                error = ESRCH;
                                goto out;
                        }
                        tmp = (int)p1->p_pgrpid;
                        proc_rele(p1);
                }
                error =  fo_ioctl(fp, (int)TIOCSPGRP, (caddr_t)&tmp, &context);
                goto out;

        case F_SETNOSIGPIPE:
                tmp = CAST_DOWN_EXPLICIT(int, uap->arg);
                if (fp->f_type == DTYPE_SOCKET) {
                        error = sock_setsockopt((struct socket *)fp->f_data,
                            SOL_SOCKET, SO_NOSIGPIPE, &tmp, sizeof (tmp));
                } else {
                        struct fileglob *fg = fp->f_fglob;

                        lck_mtx_lock_spin(&fg->fg_lock);
                        if (tmp)
                                fg->fg_lflags |= FG_NOSIGPIPE;
                        else
                                fg->fg_lflags &= FG_NOSIGPIPE;
                        lck_mtx_unlock(&fg->fg_lock);
                        error = 0;
                }
                goto out;

        case F_GETNOSIGPIPE:
                if (fp->f_type == DTYPE_SOCKET) {
                        int retsize = sizeof (*retval);
                        error = sock_getsockopt((struct socket *)fp->f_data,
                            SOL_SOCKET, SO_NOSIGPIPE, retval, &retsize);
                } else {
                        *retval = (fp->f_fglob->fg_lflags & FG_NOSIGPIPE) ?
                                1 : 0;
                        error = 0;
                }
                goto out;

        case F_SETLKW:
                flg |= F_WAIT;
                /* Fall into F_SETLK */

        case F_SETLK:
                if (fp->f_type != DTYPE_VNODE) {
                        error = EBADF;
                        goto out;
                }
                vp = (struct vnode *)fp->f_data;

                fflag = fp->f_flag;
                offset = fp->f_offset;
                proc_fdunlock(p);

                /* Copy in the lock structure */
                error = copyin(argp, (caddr_t)&fl, sizeof(fl));
                if (error) {
                        goto outdrop;
                }

                if ((fl.l_whence == SEEK_CUR) && (fl.l_start + offset < fl.l_start)) {
                    error = EOVERFLOW;
                    goto outdrop;
                }

                if ( (error = vnode_getwithref(vp)) ) {
                        goto outdrop;
                }
                if (fl.l_whence == SEEK_CUR)
                        fl.l_start += offset;

#if CONFIG_MACF
                error = mac_file_check_lock(proc_ucred(p), fp->f_fglob,
                    F_SETLK, &fl);
                if (error) {
                        (void)vnode_put(vp);
                        goto outdrop;
                }
#endif
                switch (fl.l_type) {

                case F_RDLCK:
                        if ((fflag & FREAD) == 0) {
                                (void)vnode_put(vp);
                                error = EBADF;
                                goto outdrop;
                        }
                        // XXX UInt32 unsafe for LP64 kernel
                        OSBitOrAtomic(P_LADVLOCK, &p->p_ladvflag);
                        error = VNOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &fl, flg, &context);
                        (void)vnode_put(vp);
                        goto outdrop;

                case F_WRLCK:
                        if ((fflag & FWRITE) == 0) {
                                (void)vnode_put(vp);
                                error = EBADF;
                                goto outdrop;
                        }
                        // XXX UInt32 unsafe for LP64 kernel
                        OSBitOrAtomic(P_LADVLOCK, &p->p_ladvflag);
                        error = VNOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &fl, flg, &context);
                        (void)vnode_put(vp);
                        goto outdrop;

                case F_UNLCK:
                        error = VNOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &fl,
                                F_POSIX, &context);
                        (void)vnode_put(vp);
                        goto outdrop;

                default:
                        (void)vnode_put(vp);
                        error = EINVAL;
                        goto outdrop;
                }

        case F_GETLK:
#if CONFIG_EMBEDDED
        case F_GETLKPID:
#endif
                if (fp->f_type != DTYPE_VNODE) {
                        error = EBADF;
                        goto out;
                }
                vp = (struct vnode *)fp->f_data;

                offset = fp->f_offset;
                proc_fdunlock(p);

                /* Copy in the lock structure */
                error = copyin(argp, (caddr_t)&fl, sizeof(fl));
                if (error)
                        goto outdrop;

                /* Check starting byte and ending byte for EOVERFLOW in SEEK_CUR */
                /* and ending byte for EOVERFLOW in SEEK_SET */
                if (((fl.l_whence == SEEK_CUR) && 
                     ((fl.l_start + offset < fl.l_start) ||
                      ((fl.l_len > 0) && (fl.l_start+offset + fl.l_len - 1 < fl.l_start+offset)))) ||
                    ((fl.l_whence == SEEK_SET) && (fl.l_len > 0) && (fl.l_start + fl.l_len - 1 < fl.l_start)))
                {
                        /* lf_advlock doesn't check start/end for F_GETLK if file has no locks */
                        error = EOVERFLOW;
                        goto outdrop;
                }

                if ((fl.l_whence == SEEK_SET) && (fl.l_start < 0)) {
                        error = EINVAL;
                        goto outdrop;
                }

                switch (fl.l_type) {
                case F_RDLCK:
                case F_UNLCK:
                case F_WRLCK:
                        break;
                default:
                        error = EINVAL;
                        goto outdrop;
                }

                switch (fl.l_whence) {
                case SEEK_CUR:
                case SEEK_SET:
                case SEEK_END:
                        break;
                default:
                        error = EINVAL;
                        goto outdrop;
                }

                if ( (error = vnode_getwithref(vp)) == 0 ) {
                        if (fl.l_whence == SEEK_CUR)
                                fl.l_start += offset;

#if CONFIG_MACF
                        error = mac_file_check_lock(proc_ucred(p), fp->f_fglob,
                            uap->cmd, &fl);
                        if (error == 0)
#endif
                        error = VNOP_ADVLOCK(vp, (caddr_t)p, uap->cmd, &fl, F_POSIX, &context);

                        (void)vnode_put(vp);

                        if (error == 0)
                                error = copyout((caddr_t)&fl, argp, sizeof(fl));
                }
                goto outdrop;

        case F_PREALLOCATE: {
                fstore_t alloc_struct;    /* structure for allocate command */
                u_int32_t alloc_flags = 0;

                if (fp->f_type != DTYPE_VNODE) {
                        error = EBADF;
                        goto out;
                }

                vp = (struct vnode *)fp->f_data;
                proc_fdunlock(p);

                /* make sure that we have write permission */
                if ((fp->f_flag & FWRITE) == 0) {
                        error = EBADF;
                        goto outdrop;
                }

                error = copyin(argp, (caddr_t)&alloc_struct, sizeof(alloc_struct));
                if (error)
                        goto outdrop;

                /* now set the space allocated to 0 */
                alloc_struct.fst_bytesalloc = 0;
                
                /*
                 * Do some simple parameter checking
                 */

                /* set up the flags */

                alloc_flags |= PREALLOCATE;
                
                if (alloc_struct.fst_flags & F_ALLOCATECONTIG)
                        alloc_flags |= ALLOCATECONTIG;

                if (alloc_struct.fst_flags & F_ALLOCATEALL)
                        alloc_flags |= ALLOCATEALL;

                /*
                 * Do any position mode specific stuff.  The only
                 * position mode  supported now is PEOFPOSMODE
                 */

                switch (alloc_struct.fst_posmode) {
        
                case F_PEOFPOSMODE:
                        if (alloc_struct.fst_offset != 0) {
                                error = EINVAL;
                                goto outdrop;
                        }

                        alloc_flags |= ALLOCATEFROMPEOF;
                        break;

                case F_VOLPOSMODE:
                        if (alloc_struct.fst_offset <= 0) {
                                error = EINVAL;
                                goto outdrop;
                        }

                        alloc_flags |= ALLOCATEFROMVOL;
                        break;

                default: {
                        error = EINVAL;
                        goto outdrop;
                        }
                }
                if ( (error = vnode_getwithref(vp)) == 0 ) {
                        /*
                         * call allocate to get the space
                         */
                        error = VNOP_ALLOCATE(vp,alloc_struct.fst_length,alloc_flags,
                                              &alloc_struct.fst_bytesalloc, alloc_struct.fst_offset,
                                              &context);
                        (void)vnode_put(vp);

                        error2 = copyout((caddr_t)&alloc_struct, argp, sizeof(alloc_struct));

                        if (error == 0)
                                error = error2;
                }
                goto outdrop;
                
                }
        case F_SETSIZE:
                if (fp->f_type != DTYPE_VNODE) {
                        error = EBADF;
                        goto out;
                }
                vp = (struct vnode *)fp->f_data;
                proc_fdunlock(p);

                error = copyin(argp, (caddr_t)&offset, sizeof (off_t));
                if (error)
                        goto outdrop;
                AUDIT_ARG(value64, offset);

                error = vnode_getwithref(vp);
                if (error)
                        goto outdrop;

#if CONFIG_MACF
                error = mac_vnode_check_truncate(&context,
                    fp->f_fglob->fg_cred, vp);
                if (error) {
                        (void)vnode_put(vp);
                        goto outdrop;
                }
#endif
                /*
                 * Make sure that we are root.  Growing a file
                 * without zero filling the data is a security hole 
                 * root would have access anyway so we'll allow it
                 */
                if (!is_suser()) {
                        error = EACCES;
                } else {
                        /*
                         * set the file size
                         */
                        error = vnode_setsize(vp, offset, IO_NOZEROFILL,
                            &context);
                }

                (void)vnode_put(vp);
                goto outdrop;

        case F_RDAHEAD:
                if (fp->f_type != DTYPE_VNODE) {
                        error = EBADF;
                        goto out;
                }
                if (uap->arg)
                        fp->f_fglob->fg_flag &= ~FNORDAHEAD;
                else
                        fp->f_fglob->fg_flag |= FNORDAHEAD;

                goto out;

        case F_NOCACHE:
                if (fp->f_type != DTYPE_VNODE) {
                        error = EBADF;
                        goto out;
                }
                if (uap->arg)
                        fp->f_fglob->fg_flag |= FNOCACHE;
                else
                        fp->f_fglob->fg_flag &= ~FNOCACHE;

                goto out;

        case F_NODIRECT:
                if (fp->f_type != DTYPE_VNODE) {
                        error = EBADF;
                        goto out;
                }
                if (uap->arg)
                        fp->f_fglob->fg_flag |= FNODIRECT;
                else
                        fp->f_fglob->fg_flag &= ~FNODIRECT;

                goto out;

        case F_GLOBAL_NOCACHE:
                if (fp->f_type != DTYPE_VNODE) {
                        error = EBADF;
                        goto out;
                }
                vp = (struct vnode *)fp->f_data;
                proc_fdunlock(p);

                if ( (error = vnode_getwithref(vp)) == 0 ) {

                        *retval = vnode_isnocache(vp);

                        if (uap->arg)
                                vnode_setnocache(vp);
                        else
                                vnode_clearnocache(vp);

                        (void)vnode_put(vp);
                }
                goto outdrop;

        case F_CHECK_OPENEVT:
                if (fp->f_type != DTYPE_VNODE) {
                        error = EBADF;
                        goto out;
                }
                vp = (struct vnode *)fp->f_data;
                proc_fdunlock(p);

                if ( (error = vnode_getwithref(vp)) == 0 ) {

                        *retval = vnode_is_openevt(vp);

                        if (uap->arg)
                                vnode_set_openevt(vp);
                        else
                                vnode_clear_openevt(vp);

                        (void)vnode_put(vp);
                }
                goto outdrop;

        case F_RDADVISE: {
                struct radvisory ra_struct;

                if (fp->f_type != DTYPE_VNODE) {
                        error = EBADF;
                        goto out;
                }
                vp = (struct vnode *)fp->f_data;
                proc_fdunlock(p);

                if ( (error = copyin(argp, (caddr_t)&ra_struct, sizeof(ra_struct))) )
                        goto outdrop;
                if ( (error = vnode_getwithref(vp)) == 0 ) {
                        error = VNOP_IOCTL(vp, F_RDADVISE, (caddr_t)&ra_struct, 0, &context);

                        (void)vnode_put(vp);
                }
                goto outdrop;
                }

        case F_FLUSH_DATA:

                if (fp->f_type != DTYPE_VNODE) {
                        error = EBADF;
                        goto out;
                }
                vp = (struct vnode *)fp->f_data;
                proc_fdunlock(p);

                if ( (error = vnode_getwithref(vp)) == 0 ) {
                        error = cluster_push(vp, 0);

                        (void)vnode_put(vp);
                }
                goto outdrop;


        case F_READBOOTSTRAP:
        case F_WRITEBOOTSTRAP: {
                user32_fbootstraptransfer_t user32_fbt_struct;
                user_fbootstraptransfer_t user_fbt_struct;
                int     sizeof_struct;
                caddr_t boot_structp;

                if (fp->f_type != DTYPE_VNODE) {
                        error = EBADF;
                        goto out;
                }
                vp = (struct vnode *)fp->f_data;
                proc_fdunlock(p);

                if (IS_64BIT_PROCESS(p)) {
                        sizeof_struct = sizeof(user_fbt_struct);
                        boot_structp = (caddr_t) &user_fbt_struct;
                }
                else {
                        sizeof_struct = sizeof(user32_fbt_struct);
                        boot_structp = (caddr_t) &user32_fbt_struct;
                }
                error = copyin(argp, boot_structp, sizeof_struct);
                if (error)
                        goto outdrop;
                if ( (error = vnode_getwithref(vp)) ) {
                        goto outdrop;
                }
                if (uap->cmd == F_WRITEBOOTSTRAP) {
                        /*
                         * Make sure that we are root.  Updating the
                         * bootstrap on a disk could be a security hole
                         */
                        if (!is_suser()) {
                                (void)vnode_put(vp);
                                error = EACCES;
                                goto outdrop;
                        }
                }
                if (strncmp(vnode_mount(vp)->mnt_vfsstat.f_fstypename, "hfs",
                        sizeof(vnode_mount(vp)->mnt_vfsstat.f_fstypename)) != 0) {
                        error = EINVAL;
                } else {
                        /*
                         * call vnop_ioctl to handle the I/O
                         */
                        error = VNOP_IOCTL(vp, uap->cmd, boot_structp, 0, &context);
                }
                (void)vnode_put(vp);
                goto outdrop;
        }
        case F_LOG2PHYS:
        case F_LOG2PHYS_EXT: {
                struct log2phys l2p_struct;    /* structure for allocate command */
                int devBlockSize;

                off_t file_offset = 0;
                size_t a_size = 0;
                size_t run = 0;

                if (uap->cmd == F_LOG2PHYS_EXT) {
                        error = copyin(argp, (caddr_t)&l2p_struct, sizeof(l2p_struct));
                        if (error)
                                goto out;
                        file_offset = l2p_struct.l2p_devoffset;
                } else {
                        file_offset = fp->f_offset;
                }
                if (fp->f_type != DTYPE_VNODE) {
                        error = EBADF;
                        goto out;
                }
                vp = (struct vnode *)fp->f_data;
                proc_fdunlock(p);
                if ( (error = vnode_getwithref(vp)) ) {
                        goto outdrop;
                }
                error = VNOP_OFFTOBLK(vp, file_offset, &lbn);
                if (error) {
                        (void)vnode_put(vp);
                        goto outdrop;
                }
                error = VNOP_BLKTOOFF(vp, lbn, &offset);
                if (error) {
                        (void)vnode_put(vp);
                        goto outdrop;
                }
                devBlockSize = vfs_devblocksize(vnode_mount(vp));
                if (uap->cmd == F_LOG2PHYS_EXT) {
                        a_size = l2p_struct.l2p_contigbytes;
                } else {
                        a_size = devBlockSize;
                }
                
                error = VNOP_BLOCKMAP(vp, offset, a_size, &bn, &run, NULL, 0, &context);

                (void)vnode_put(vp);

                if (!error) {
                        l2p_struct.l2p_flags = 0;       /* for now */
                        if (uap->cmd == F_LOG2PHYS_EXT) {
                                l2p_struct.l2p_contigbytes = run - (file_offset - offset);
                        } else {
                                l2p_struct.l2p_contigbytes = 0; /* for now */
                        }
                        l2p_struct.l2p_devoffset = bn * devBlockSize;
                        l2p_struct.l2p_devoffset += file_offset - offset;
                        error = copyout((caddr_t)&l2p_struct, argp, sizeof(l2p_struct));
                }
                goto outdrop;
                }
        case F_GETPATH: {
                char *pathbufp;
                int pathlen;

                if (fp->f_type != DTYPE_VNODE) {
                        error = EBADF;
                        goto out;
                }
                vp = (struct vnode *)fp->f_data;
                proc_fdunlock(p);

                pathlen = MAXPATHLEN;
                MALLOC(pathbufp, char *, pathlen, M_TEMP, M_WAITOK);
                if (pathbufp == NULL) {
                        error = ENOMEM;
                        goto outdrop;
                }
                if ( (error = vnode_getwithref(vp)) == 0 ) {
                        error = vn_getpath(vp, pathbufp, &pathlen);
                        (void)vnode_put(vp);

                        if (error == 0)
                                error = copyout((caddr_t)pathbufp, argp, pathlen);
                }
                FREE(pathbufp, M_TEMP);
                goto outdrop;
        }

        case F_PATHPKG_CHECK: {
                char *pathbufp;
                size_t pathlen;

                if (fp->f_type != DTYPE_VNODE) {
                        error = EBADF;
                        goto out;
                }
                vp = (struct vnode *)fp->f_data;
                proc_fdunlock(p);

                pathlen = MAXPATHLEN;
                pathbufp = kalloc(MAXPATHLEN);

                if ( (error = copyinstr(argp, pathbufp, MAXPATHLEN, &pathlen)) == 0 ) {
                        if ( (error = vnode_getwithref(vp)) == 0 ) {
                                AUDIT_ARG(text, pathbufp);
                                error = vn_path_package_check(vp, pathbufp, pathlen, retval);

                                (void)vnode_put(vp);
                        }
                }
                kfree(pathbufp, MAXPATHLEN);
                goto outdrop;
        }

        case F_CHKCLEAN:   // used by regression tests to see if all dirty pages got cleaned by fsync()
        case F_FULLFSYNC:  // fsync + flush the journal + DKIOCSYNCHRONIZECACHE
        case F_FREEZE_FS:  // freeze all other fs operations for the fs of this fd
        case F_THAW_FS: {  // thaw all frozen fs operations for the fs of this fd
                if (fp->f_type != DTYPE_VNODE) {
                        error = EBADF;
                        goto out;
                }
                vp = (struct vnode *)fp->f_data;
                proc_fdunlock(p);

                if ( (error = vnode_getwithref(vp)) == 0 ) {
                        error = VNOP_IOCTL(vp, uap->cmd, (caddr_t)NULL, 0, &context);

                        (void)vnode_put(vp);
                }
                break;
        }

        /*
         * SPI (private) for opening a file starting from a dir fd
         */
        case F_OPENFROM: {
                struct user_fopenfrom fopen;
                struct vnode_attr va;
                struct nameidata nd;
                int cmode;

                /* Check if this isn't a valid file descriptor */
                if ((fp->f_type != DTYPE_VNODE) ||
                    (fp->f_flag & FREAD) == 0) {
                        error = EBADF;
                        goto out;
                }
                vp = (struct vnode *)fp->f_data;
                proc_fdunlock(p);

                if (vnode_getwithref(vp)) {
                        error = ENOENT;
                        goto outdrop;
                }
                
                /* Only valid for directories */
                if (vp->v_type != VDIR) {
                        vnode_put(vp);
                        error = ENOTDIR;
                        goto outdrop;
                }

                /* Get flags, mode and pathname arguments. */
                if (IS_64BIT_PROCESS(p)) {
                        error = copyin(argp, &fopen, sizeof(fopen));
                } else {
                        struct user32_fopenfrom fopen32;

                        error = copyin(argp, &fopen32, sizeof(fopen32));
                        fopen.o_flags = fopen32.o_flags;
                        fopen.o_mode = fopen32.o_mode;
                        fopen.o_pathname = CAST_USER_ADDR_T(fopen32.o_pathname);
                }
                if (error) {
                        vnode_put(vp);
                        goto outdrop;
                }
                AUDIT_ARG(fflags, fopen.o_flags);
                AUDIT_ARG(mode, fopen.o_mode);
                VATTR_INIT(&va);
                /* Mask off all but regular access permissions */
                cmode = ((fopen.o_mode &~ fdp->fd_cmask) & ALLPERMS) & ~S_ISTXT;
                VATTR_SET(&va, va_mode, cmode & ACCESSPERMS);

                /* Start the lookup relative to the file descriptor's vnode. */
                NDINIT(&nd, LOOKUP, OP_OPEN, USEDVP | FOLLOW | AUDITVNPATH1, UIO_USERSPACE,
                       fopen.o_pathname, &context);
                nd.ni_dvp = vp;

                error = open1(&context, &nd, fopen.o_flags, &va, retval);

                vnode_put(vp);
                break;
        }
        /*
         * SPI (private) for unlinking a file starting from a dir fd
         */
        case F_UNLINKFROM: {
                struct nameidata nd;
                user_addr_t pathname;

                /* Check if this isn't a valid file descriptor */
                if ((fp->f_type != DTYPE_VNODE) ||
                    (fp->f_flag & FREAD) == 0) {
                        error = EBADF;
                        goto out;
                }
                vp = (struct vnode *)fp->f_data;
                proc_fdunlock(p);

                if (vnode_getwithref(vp)) {
                        error = ENOENT;
                        goto outdrop;
                }
                
                /* Only valid for directories */
                if (vp->v_type != VDIR) {
                        vnode_put(vp);
                        error = ENOTDIR;
                        goto outdrop;
                }

                /* Get flags, mode and pathname arguments. */
                if (IS_64BIT_PROCESS(p)) {
                        pathname = (user_addr_t)argp;
                } else {
                        pathname = CAST_USER_ADDR_T(argp);
                }

                /* Start the lookup relative to the file descriptor's vnode. */
                NDINIT(&nd, DELETE, OP_UNLINK, USEDVP | AUDITVNPATH1, UIO_USERSPACE,
                       pathname, &context);
                nd.ni_dvp = vp;

                error = unlink1(&context, &nd, 0);
                
                vnode_put(vp);
                break;

        }

        case F_ADDSIGS:
        case F_ADDFILESIGS:
        {
                struct user_fsignatures fs;
                kern_return_t kr;
                vm_offset_t kernel_blob_addr;
                vm_size_t kernel_blob_size;

                if (fp->f_type != DTYPE_VNODE) {
                        error = EBADF;
                        goto out;
                }
                vp = (struct vnode *)fp->f_data;
                proc_fdunlock(p);
                error = vnode_getwithref(vp);
                if (error)
                        goto outdrop;

                if (IS_64BIT_PROCESS(p)) {
                        error = copyin(argp, &fs, sizeof (fs));
                } else {
                        struct user32_fsignatures fs32;

                        error = copyin(argp, &fs32, sizeof (fs32));
                        fs.fs_file_start = fs32.fs_file_start;
                        fs.fs_blob_start = CAST_USER_ADDR_T(fs32.fs_blob_start);
                        fs.fs_blob_size = fs32.fs_blob_size;
                }

                if (error) {
                        vnode_put(vp);
                        goto outdrop;
                }

                if(ubc_cs_blob_get(vp, CPU_TYPE_ANY, fs.fs_file_start))
                {
                        /*
                        if(cs_debug)
                                printf("CODE SIGNING: resident blob offered for: %s\n", vp->v_name);
                         */
                        vnode_put(vp);
                        goto outdrop;
                }
                                   
#define CS_MAX_BLOB_SIZE (1ULL * 1024 * 1024) /* XXX ? */
                if (fs.fs_blob_size > CS_MAX_BLOB_SIZE) {
                        error = E2BIG;
                        vnode_put(vp);
                        goto outdrop;
                }

                kernel_blob_size = CAST_DOWN(vm_size_t, fs.fs_blob_size);
                kr = ubc_cs_blob_allocate(&kernel_blob_addr, &kernel_blob_size);
                if (kr != KERN_SUCCESS) {
                        error = ENOMEM;
                        vnode_put(vp);
                        goto outdrop;
                }

                if(uap->cmd == F_ADDSIGS) {
                        error = copyin(fs.fs_blob_start,
                                       (void *) kernel_blob_addr,
                                       kernel_blob_size);
                } else /* F_ADDFILESIGS */ {
                        error = vn_rdwr(UIO_READ,
                                        vp,
                                        (caddr_t) kernel_blob_addr,
                                        kernel_blob_size,
                                         fs.fs_file_start + fs.fs_blob_start,
                                        UIO_SYSSPACE,
                                        0,
                                        kauth_cred_get(),
                                        0,
                                        p);
                }
                
                if (error) {
                        ubc_cs_blob_deallocate(kernel_blob_addr,
                                               kernel_blob_size);
                        vnode_put(vp);
                        goto outdrop;
                }

                error = ubc_cs_blob_add(
                        vp,
                        CPU_TYPE_ANY,   /* not for a specific architecture */
                        fs.fs_file_start,
                        kernel_blob_addr,
                        kernel_blob_size);
                if (error) {
                        ubc_cs_blob_deallocate(kernel_blob_addr,
                                               kernel_blob_size);
                } else {
                        /* ubc_blob_add() has consumed "kernel_blob_addr" */
#if CHECK_CS_VALIDATION_BITMAP
                        ubc_cs_validation_bitmap_allocate( vp );
#endif
                }

                (void) vnode_put(vp);
                break;
        }

        case F_MARKDEPENDENCY: {
                struct vnode_attr va;
                vfs_context_t ctx = vfs_context_current();
                kauth_cred_t cred;

                if ((current_proc()->p_flag & P_DEPENDENCY_CAPABLE) == 0) {
                    error = EPERM;
                    goto out;
                }
                
                if (fp->f_type != DTYPE_VNODE) {
                        error = EBADF;
                        goto out;
                }

                vp = (struct vnode *)fp->f_data;
                proc_fdunlock(p);

                if (vnode_getwithref(vp)) {
                        error = ENOENT;
                        goto outdrop;
                }

                if (!vnode_isvroot(vp)) {
                    error = EINVAL;
                    vnode_put(vp);
                    goto outdrop;
                }

                // get the owner of the root dir
                VATTR_INIT(&va);
                VATTR_WANTED(&va, va_uid);
                if (vnode_getattr(vp, &va, ctx) != 0) {
                    error = EINVAL;
                    vnode_put(vp);
                    goto outdrop;
                }

                // and last, check that the caller is the super user or
                // the owner of the mount point
                cred = vfs_context_ucred(ctx);
                if (!is_suser() && va.va_uid != kauth_cred_getuid(cred)) {
                        error = EACCES;
                        vnode_put(vp);
                        goto outdrop;
                }

                // if all those checks pass then we can mark the dependency
                vfs_markdependency(vp->v_mount);
                error = 0;
                
                vnode_put(vp);
                
                break;
        }
                        
#ifdef CONFIG_PROTECT
        case F_GETPROTECTIONCLASS: {
                int class = 0;
                
                if (fp->f_type != DTYPE_VNODE) {
                        error = EBADF;
                        goto out;
                }
                vp = (struct vnode *)fp->f_data;

                proc_fdunlock(p);

                if (vnode_getwithref(vp)) {
                        error = ENOENT;
                        goto outdrop;
                }
        
                error = cp_vnode_getclass (vp, &class);
                if (error == 0) {
                        *retval = class;
                }

                vnode_put(vp);
                break;
        }
        
        case F_SETPROTECTIONCLASS: {
                /* tmp must be a valid PROTECTION_CLASS_* */
                tmp = CAST_DOWN_EXPLICIT(uint32_t, uap->arg);
                
                if (fp->f_type != DTYPE_VNODE) {
                        error = EBADF;
                        goto out;
                }
                vp = (struct vnode *)fp->f_data;

                proc_fdunlock(p);
        
                if (vnode_getwithref(vp)) {
                        error = ENOENT;
                        goto outdrop;
                }       
                
                /* Only go forward if you have write access */
                vfs_context_t ctx = vfs_context_current();
                if(vnode_authorize(vp, NULLVP, (KAUTH_VNODE_ACCESS | KAUTH_VNODE_WRITE_DATA), ctx) != 0) {
                        vnode_put(vp);
                        error = EBADF;
                        goto outdrop;
                }
                error = cp_vnode_setclass (vp, tmp);
                vnode_put(vp);
                break;
        }       
#endif /* CONFIG_PROTECT */
                        
        case F_MOVEDATAEXTENTS: {
                struct fileproc *fp2 = NULL;
                struct vnode *src_vp = NULLVP;
                struct vnode *dst_vp = NULLVP;
                /* We need to grab the 2nd FD out of the argments before moving on. */
                int fd2 = CAST_DOWN_EXPLICIT(int32_t, uap->arg);

                if (fp->f_type != DTYPE_VNODE) {
                        error = EBADF;
                        goto out;
                }
                vp = src_vp = (struct vnode *)fp->f_data;

                /* For now, special case HFS+ only, since this is SPI. */
                if (src_vp->v_tag != VT_HFS) {
                        error = EINVAL;
                        goto out;
                }

                /* We're still holding the proc FD lock */
                if ( (error = fp_lookup(p, fd2, &fp2, 1)) ) {
                        error = EBADF;
                        goto out;
                }
                if (fp2->f_type != DTYPE_VNODE) {
                        fp_drop(p, fd2, fp2, 1);
                        error = EBADF;
                        goto out;
                }
                dst_vp = (struct vnode *)fp2->f_data;

                /* For now, special case HFS+ only, since this is SPI. */
                if (dst_vp->v_tag != VT_HFS) {
                        fp_drop(p, fd2, fp2, 1);
                        error = EINVAL;
                        goto out;
                }

#if CONFIG_MACF
                /* Re-do MAC checks against the new FD, pass in a fake argument */
                error = mac_file_check_fcntl(proc_ucred(p), fp2->f_fglob, uap->cmd, 0);
                if (error) {
                        fp_drop(p, fd2, fp2, 1);
                        goto out;
                }
#endif
                /* Audit the 2nd FD */
                AUDIT_ARG(fd, fd2);

                proc_fdunlock(p);

                /* Proc lock dropped; now we have a legit pair of FDs.  Go to work */

                if (vnode_getwithref(src_vp)) {
                        fp_drop(p, fd2, fp2, 0);
                        error = ENOENT;
                        goto outdrop;
                }       
                if (vnode_getwithref(dst_vp)) {
                        vnode_put (src_vp);
                        fp_drop(p, fd2, fp2, 0);
                        error = ENOENT;
                        goto outdrop;
                }       

                /* 
                 * Basic asserts; validate they are not the same and that
                 * both live on the same filesystem.
                 */

                if (dst_vp == src_vp) {
                        vnode_put (src_vp);
                        vnode_put (dst_vp);
                        fp_drop (p, fd2, fp2, 0);
                        error = EINVAL;
                        goto outdrop;
                }       
        
                if (dst_vp->v_mount != src_vp->v_mount) {
                        vnode_put (src_vp);
                        vnode_put (dst_vp);
                        fp_drop (p, fd2, fp2, 0);
                        error = EXDEV;
                        goto outdrop;
                }

                /* Now check for write access to the target files */
                if(vnode_authorize(src_vp, NULLVP, 
                                        (KAUTH_VNODE_ACCESS | KAUTH_VNODE_WRITE_DATA), &context) != 0) {
                        vnode_put(src_vp);
                        vnode_put(dst_vp);
                        fp_drop(p, fd2, fp2, 0);
                        error = EBADF;
                        goto outdrop;
                }

                if(vnode_authorize(dst_vp, NULLVP, 
                                        (KAUTH_VNODE_ACCESS | KAUTH_VNODE_WRITE_DATA), &context) != 0) {
                        vnode_put(src_vp);
                        vnode_put(dst_vp);
                        fp_drop(p, fd2, fp2, 0);
                        error = EBADF;
                        goto outdrop;
                }

                /* Verify that both vps point to files and not directories */
                if (!vnode_isreg(src_vp) || !vnode_isreg(dst_vp)) {
                        vnode_put(src_vp);
                        vnode_put(dst_vp);
                        fp_drop(p, fd2, fp2, 0);
                        error = EINVAL;
                        goto outdrop;
                }

                /* 
                 * The exchangedata syscall handler passes in 0 for the flags to VNOP_EXCHANGE.
                 * We'll pass in our special bit indicating that the new behavior is expected
                 */

                error = VNOP_EXCHANGE(src_vp, dst_vp, FSOPT_EXCHANGE_DATA_ONLY, &context);

                vnode_put (src_vp);
                vnode_put (dst_vp);
                fp_drop(p, fd2, fp2, 0);
                break;
        }

        /* 
         * Set the vnode pointed to by 'fd'
         * and tag it as the (potentially future) backing store
         * for another filesystem
         */
        case F_SETBACKINGSTORE: {
                if (fp->f_type != DTYPE_VNODE) {
                        error = EBADF;
                        goto out;
                }
                vp = (struct vnode *)fp->f_data;
                
                if (vp->v_tag != VT_HFS) {
                        error = EINVAL;
                        goto out;

                }
                proc_fdunlock(p);

                if (vnode_getwithref(vp)) {
                        error = ENOENT;
                        goto outdrop;
                }
                
                /* only proceed if you have write access */
                vfs_context_t ctx = vfs_context_current();
                if(vnode_authorize(vp, NULLVP, (KAUTH_VNODE_ACCESS | KAUTH_VNODE_WRITE_DATA), ctx) != 0) {
                        vnode_put(vp);
                        error = EBADF;
                        goto outdrop;
                }

                
                /* If arg != 0, set, otherwise unset */
                if (uap->arg) {
                        error = hfs_set_backingstore (vp, 1);
                }
                else {
                        error = hfs_set_backingstore (vp, 0);
                }
                /* Success. explicitly set error to 0. */
                error = 0;

                vnode_put(vp);
                break;
        }

        /* 
         * like F_GETPATH, but special semantics for
         * the mobile time machine handler.
         */
        case F_GETPATH_MTMINFO: {
                char *pathbufp;
                int pathlen;

                if (fp->f_type != DTYPE_VNODE) {
                        error = EBADF;
                        goto out;
                }
                vp = (struct vnode *)fp->f_data;
                proc_fdunlock(p);

                pathlen = MAXPATHLEN;
                MALLOC(pathbufp, char *, pathlen, M_TEMP, M_WAITOK);
                if (pathbufp == NULL) {
                        error = ENOMEM;
                        goto outdrop;
                }
                if ( (error = vnode_getwithref(vp)) == 0 ) {
                        int backingstore = 0;
                        
                        /* Check for error from vn_getpath before moving on */
                        if ((error = vn_getpath(vp, pathbufp, &pathlen)) == 0) {
                                if (vp->v_tag == VT_HFS) {
                                        error = hfs_is_backingstore (vp, &backingstore);
                                }
                                (void)vnode_put(vp);

                                if (error == 0) {
                                        error = copyout((caddr_t)pathbufp, argp, pathlen);
                                }
                                if (error == 0) {
                                        /* 
                                         * If the copyout was successful, now check to ensure
                                         * that this vnode is not a BACKINGSTORE vnode.  mtmd
                                         * wants the path regardless.
                                         */
                                        if (backingstore) {
                                                error = EBUSY;
                                        }
                                }
                        } else
                                (void)vnode_put(vp);
                }
                FREE(pathbufp, M_TEMP);
                goto outdrop;
        }


        default:
                /*
                 * This is an fcntl() that we d not recognize at this level;
                 * if this is a vnode, we send it down into the VNOP_IOCTL
                 * for this vnode; this can include special devices, and will
                 * effectively overload fcntl() to send ioctl()'s.
                 */
                if((uap->cmd & IOC_VOID) && (uap->cmd & IOC_INOUT)){
                        error = EINVAL;
                        goto out;
                }
                
                if (fp->f_type != DTYPE_VNODE) {
                        error = EBADF;
                        goto out;
                }
                vp = (struct vnode *)fp->f_data;
                proc_fdunlock(p);

                if ( (error = vnode_getwithref(vp)) == 0 ) {
#define STK_PARAMS 128
                        char stkbuf[STK_PARAMS];
                        unsigned int size;
                        caddr_t data, memp;
                        /*
                         * For this to work properly, we have to copy in the
                         * ioctl() cmd argument if there is one; we must also
                         * check that a command parameter, if present, does
                         * not exceed the maximum command length dictated by
                         * the number of bits we have available in the command
                         * to represent a structure length.  Finally, we have
                         * to copy the results back out, if it is that type of
                         * ioctl().
                         */
                        size = IOCPARM_LEN(uap->cmd);
                        if (size > IOCPARM_MAX) {
                                (void)vnode_put(vp);
                                error = EINVAL;
                                break;
                        }

                        memp = NULL;
                        if (size > sizeof (stkbuf)) {
                                if ((memp = (caddr_t)kalloc(size)) == 0) {
                                        (void)vnode_put(vp);
                                        error = ENOMEM;
                                        goto outdrop;
                                }
                                data = memp;
                        } else {
                                data = &stkbuf[0];
                        }
                        
                        if (uap->cmd & IOC_IN) {
                                if (size) {
                                        /* structure */
                                        error = copyin(argp, data, size);
                                        if (error) {
                                                (void)vnode_put(vp);
                                                if (memp)
                                                        kfree(memp, size);
                                                goto outdrop;
                                        }
                                } else {
                                        /* int */
                                        if (is64bit) {
                                                *(user_addr_t *)data = argp;
                                        } else {
                                                *(uint32_t *)data = (uint32_t)argp;
                                        }
                                };
                        } else if ((uap->cmd & IOC_OUT) && size) {
                                /*
                                 * Zero the buffer so the user always
                                 * gets back something deterministic.
                                 */
                                bzero(data, size);
                        } else if (uap->cmd & IOC_VOID) {
                                if (is64bit) {
                                    *(user_addr_t *)data = argp;
                                } else {
                                    *(uint32_t *)data = (uint32_t)argp;
                                }
                        }

                        error = VNOP_IOCTL(vp, uap->cmd, CAST_DOWN(caddr_t, data), 0, &context);

                        (void)vnode_put(vp);

                        /* Copy any output data to user */
                        if (error == 0 && (uap->cmd & IOC_OUT) && size) 
                                error = copyout(data, argp, size);
                        if (memp)
                                kfree(memp, size);
                }
                break;
        }

outdrop:
        AUDIT_ARG(vnpath_withref, vp, ARG_VNODE1);
        fp_drop(p, fd, fp, 0);
        return(error);
out:
        fp_drop(p, fd, fp, 1);
        proc_fdunlock(p);
        return(error);
}


/*
 * finishdup
 *
 * Description: Common code for dup, dup2, and fcntl(F_DUPFD).
 *
 * Parameters:  p                               Process performing the dup
 *              old                             The fd to dup
 *              new                             The fd to dup it to
 *              fd_flags                        Flags to augment the new fd
 *              retval                          Pointer to the call return area
 *
 * Returns:     0                               Success
 *              EBADF
 *              ENOMEM
 *
 * Implicit returns:
 *              *retval (modified)              The new descriptor
 *
 * Locks:       Assumes proc_fdlock for process pointing to fdp is held by
 *              the caller
 *
 * Notes:       This function may drop and reacquire this lock; it is unsafe
 *              for a caller to assume that other state protected by the lock
 *              has not been subsequently changed out from under it.
 */
int
finishdup(proc_t p,
    struct filedesc *fdp, int old, int new, int fd_flags, int32_t *retval)
{
        struct fileproc *nfp;
        struct fileproc *ofp;
#if CONFIG_MACF
        int error;
#endif

#if DIAGNOSTIC
        proc_fdlock_assert(p, LCK_MTX_ASSERT_OWNED);
#endif
        if ((ofp = fdp->fd_ofiles[old]) == NULL ||
            (fdp->fd_ofileflags[old] & UF_RESERVED)) {
                fdrelse(p, new);
                return (EBADF);
        }
        fg_ref(ofp);

#if CONFIG_MACF
        error = mac_file_check_dup(proc_ucred(p), ofp->f_fglob, new);
        if (error) {
                fg_drop(ofp);
                fdrelse(p, new);
                return (error);
        }
#endif

        proc_fdunlock(p);

        MALLOC_ZONE(nfp, struct fileproc *, sizeof(struct fileproc), M_FILEPROC, M_WAITOK);
        /* Failure check follows proc_fdlock() due to handling requirements */

        proc_fdlock(p);

        if (nfp == NULL) {
                fg_drop(ofp);
                fdrelse(p, new);
                return (ENOMEM);
        }

        bzero(nfp, sizeof(struct fileproc));

        nfp->f_flags = 0;
        nfp->f_fglob = ofp->f_fglob;
        nfp->f_iocount = 0;

#if DIAGNOSTIC
        if (fdp->fd_ofiles[new] != 0)
                panic("finishdup: overwriting fd_ofiles with new %d", new);
        if ((fdp->fd_ofileflags[new] & UF_RESERVED) == 0)
                panic("finishdup: unreserved fileflags with new %d", new);
#endif

        if (new > fdp->fd_lastfile)
                fdp->fd_lastfile = new;
        *fdflags(p, new) |= fd_flags;
        procfdtbl_releasefd(p, new, nfp);
        *retval = new;
        return (0);
}


/*
 * close
 *
 * Description: The implementation of the close(2) system call
 *
 * Parameters:  p                       Process in whose per process file table
 *                                      the close is to occur
 *              uap->fd                 fd to be closed
 *              retval                  <unused>
 *
 * Returns:     0                       Success
 *      fp_lookup:EBADF                 Bad file descriptor
 *      close_internal:EBADF
 *      close_internal:???              Anything returnable by a per-fileops
 *                                      close function
 */
int
close(proc_t p, struct close_args *uap, int32_t *retval)
{
        __pthread_testcancel(1);
        return(close_nocancel(p, (struct close_nocancel_args *)uap, retval));
}


int
close_nocancel(proc_t p, struct close_nocancel_args *uap, __unused int32_t *retval)
{
        struct fileproc *fp;
        int fd = uap->fd;
        int error =0;

        AUDIT_SYSCLOSE(p, fd);

        proc_fdlock(p);

        if ( (error = fp_lookup(p,fd,&fp, 1)) ) {
                proc_fdunlock(p);
                return(error);
        }

        error = close_internal_locked(p, fd, fp, 0);

        proc_fdunlock(p);

        return(error);
}


/*
 * close_internal_locked
 *
 * Close a file descriptor.
 *
 * Parameters:  p                       Process in whose per process file table
 *                                      the close is to occur
 *              fd                      fd to be closed
 *              fp                      fileproc associated with the fd
 *
 * Returns:     0                       Success
 *              EBADF                   fd already in close wait state
 *      closef_locked:???               Anything returnable by a per-fileops
 *                                      close function
 *
 * Locks:       Assumes proc_fdlock for process is held by the caller and returns
 *              with lock held
 *
 * Notes:       This function may drop and reacquire this lock; it is unsafe
 *              for a caller to assume that other state protected by the lock
 *              has not been subsequently changes out from under it, if the
 *              caller made the call with the lock held.
 */
static int
close_internal_locked(proc_t p, int fd, struct fileproc *fp, int flags)
{
        struct filedesc *fdp = p->p_fd;
        int error =0;
        int resvfd = flags & FD_DUP2RESV;


#if DIAGNOSTIC
        proc_fdlock_assert(p, LCK_MTX_ASSERT_OWNED);
#endif

        /* Keep people from using the filedesc while we are closing it */
        procfdtbl_markclosefd(p, fd);


        if ((fp->f_flags & FP_CLOSING) == FP_CLOSING) {
                panic("close_internal_locked: being called on already closing fd");
        }


#if DIAGNOSTIC
        if ((fdp->fd_ofileflags[fd] & UF_RESERVED) == 0)
                panic("close_internal: unreserved fileflags with fd %d", fd);
#endif

        fp->f_flags |= FP_CLOSING;

        if ( (fp->f_flags & FP_AIOISSUED) || kauth_authorize_fileop_has_listeners() ) {

                proc_fdunlock(p);

                if ( (fp->f_type == DTYPE_VNODE) && kauth_authorize_fileop_has_listeners() ) {
                        /*
                         * call out to allow 3rd party notification of close. 
                         * Ignore result of kauth_authorize_fileop call.
                         */
                        if (vnode_getwithref((vnode_t)fp->f_data) == 0) {
                                u_int   fileop_flags = 0;
                                if ((fp->f_flags & FP_WRITTEN) != 0)
                                        fileop_flags |= KAUTH_FILEOP_CLOSE_MODIFIED;
                                kauth_authorize_fileop(fp->f_fglob->fg_cred, KAUTH_FILEOP_CLOSE, 
                                                       (uintptr_t)fp->f_data, (uintptr_t)fileop_flags);
                                vnode_put((vnode_t)fp->f_data);
                        }
                }
                if (fp->f_flags & FP_AIOISSUED)
                        /*
                         * cancel all async IO requests that can be cancelled.
                         */
                        _aio_close( p, fd );

                proc_fdlock(p);
        }

        if (fd < fdp->fd_knlistsize)
                knote_fdclose(p, fd);

        if (fp->f_flags & FP_WAITEVENT) 
                (void)waitevent_close(p, fp);

        if ((fp->f_flags & FP_INCHRREAD) == 0)
                fileproc_drain(p, fp);

        if (resvfd == 0)
                _fdrelse(p, fd);

        error = closef_locked(fp, fp->f_fglob, p);
        if ((fp->f_flags & FP_WAITCLOSE) == FP_WAITCLOSE)
                wakeup(&fp->f_flags);
        fp->f_flags &= ~(FP_WAITCLOSE | FP_CLOSING);

        proc_fdunlock(p);

        FREE_ZONE(fp, sizeof(*fp), M_FILEPROC); 

        proc_fdlock(p);

#if DIAGNOSTIC
        if (resvfd != 0) {
                if ((fdp->fd_ofileflags[fd] & UF_RESERVED) == 0)
                        panic("close with reserved fd returns with freed fd:%d: proc: %p", fd, p);
        }
#endif

        return(error);
}


/*
 * fstat1
 *
 * Description: Return status information about a file descriptor.
 *
 * Parameters:  p                               The process doing the fstat
 *              fd                              The fd to stat
 *              ub                              The user stat buffer
 *              xsecurity                       The user extended security
 *                                              buffer, or 0 if none
 *              xsecurity_size                  The size of xsecurity, or 0
 *                                              if no xsecurity
 *              isstat64                        Flag to indicate 64 bit version
 *                                              for inode size, etc.
 *
 * Returns:     0                               Success
 *              EBADF
 *              EFAULT
 *      fp_lookup:EBADF                         Bad file descriptor
 *      vnode_getwithref:???
 *      copyout:EFAULT
 *      vnode_getwithref:???
 *      vn_stat:???
 *      soo_stat:???
 *      pipe_stat:???
 *      pshm_stat:???
 *      kqueue_stat:???
 *
 * Notes:       Internal implementation for all other fstat() related
 *              functions
 *
 *              XXX switch on node type is bogus; need a stat in struct
 *              XXX fileops instead.
 */
static int
fstat1(proc_t p, int fd, user_addr_t ub, user_addr_t xsecurity, user_addr_t xsecurity_size, int isstat64)
{
        struct fileproc *fp;
        union {
                struct stat sb;
                struct stat64 sb64;
        } source;
        union {
                struct user64_stat user64_sb;
                struct user32_stat user32_sb;
                struct user64_stat64 user64_sb64;
                struct user32_stat64 user32_sb64;
        } dest;
        int error, my_size;
        int funnel_state;
        file_type_t type;
        caddr_t data;
        kauth_filesec_t fsec;
        user_size_t xsecurity_bufsize;
        vfs_context_t ctx = vfs_context_current();
        void * sbptr;


        AUDIT_ARG(fd, fd);

        if ((error = fp_lookup(p, fd, &fp, 0)) != 0) {
                return(error);
        }
        type = fp->f_type;
        data = fp->f_data;
        fsec = KAUTH_FILESEC_NONE;

        sbptr = (void *)&source;

        switch (type) {

        case DTYPE_VNODE:
                if ((error = vnode_getwithref((vnode_t)data)) == 0) {
                        /*
                         * If the caller has the file open, and is not
                         * requesting extended security information, we are
                         * going to let them get the basic stat information.
                         */
                        if (xsecurity == USER_ADDR_NULL) {
                                error = vn_stat_noauth((vnode_t)data, sbptr, NULL, isstat64, ctx);
                        } else {
                                error = vn_stat((vnode_t)data, sbptr, &fsec, isstat64, ctx);
                        }

                        AUDIT_ARG(vnpath, (struct vnode *)data, ARG_VNODE1);
                        (void)vnode_put((vnode_t)data);
                }
                break;

#if SOCKETS
        case DTYPE_SOCKET:
                error = soo_stat((struct socket *)data, sbptr, isstat64);
                break;
#endif /* SOCKETS */

        case DTYPE_PIPE:
                error = pipe_stat((void *)data, sbptr, isstat64);
                break;

        case DTYPE_PSXSHM:
                error = pshm_stat((void *)data, sbptr, isstat64);
                break;

        case DTYPE_KQUEUE:
                funnel_state = thread_funnel_set(kernel_flock, TRUE);
                error = kqueue_stat(fp, sbptr, isstat64, p);
                thread_funnel_set(kernel_flock, funnel_state);
                break;

        default:
                error = EBADF;
                goto out;
        }
        if (error == 0) {
                caddr_t sbp;

                if (isstat64 != 0) {
                        source.sb64.st_lspare = 0;
                        source.sb64.st_qspare[0] = 0LL;
                        source.sb64.st_qspare[1] = 0LL;

                        if (IS_64BIT_PROCESS(current_proc())) {
                                munge_user64_stat64(&source.sb64, &dest.user64_sb64); 
                                my_size = sizeof(dest.user64_sb64);
                                sbp = (caddr_t)&dest.user64_sb64;
                        } else {
                                munge_user32_stat64(&source.sb64, &dest.user32_sb64); 
                                my_size = sizeof(dest.user32_sb64);
                                sbp = (caddr_t)&dest.user32_sb64;
                        }
                } else {
                        source.sb.st_lspare = 0;
                        source.sb.st_qspare[0] = 0LL;
                        source.sb.st_qspare[1] = 0LL;
                        if (IS_64BIT_PROCESS(current_proc())) {
                                munge_user64_stat(&source.sb, &dest.user64_sb); 
                                my_size = sizeof(dest.user64_sb);
                                sbp = (caddr_t)&dest.user64_sb;
                        } else {
                                munge_user32_stat(&source.sb, &dest.user32_sb); 
                                my_size = sizeof(dest.user32_sb);
                                sbp = (caddr_t)&dest.user32_sb;
                        }
                }

                error = copyout(sbp, ub, my_size);
        }

        /* caller wants extended security information? */
        if (xsecurity != USER_ADDR_NULL) {

                /* did we get any? */
                 if (fsec == KAUTH_FILESEC_NONE) {
                        if (susize(xsecurity_size, 0) != 0) {
                                error = EFAULT;
                                goto out;
                        }
                } else {
                        /* find the user buffer size */
                        xsecurity_bufsize = fusize(xsecurity_size);

                        /* copy out the actual data size */
                        if (susize(xsecurity_size, KAUTH_FILESEC_COPYSIZE(fsec)) != 0) {
                                error = EFAULT;
                                goto out;
                        }

                        /* if the caller supplied enough room, copy out to it */
                        if (xsecurity_bufsize >= KAUTH_FILESEC_COPYSIZE(fsec))
                                error = copyout(fsec, xsecurity, KAUTH_FILESEC_COPYSIZE(fsec));
                }
        }
out:
        fp_drop(p, fd, fp, 0);
        if (fsec != NULL)
                kauth_filesec_free(fsec);
        return (error);
}


/*
 * fstat_extended
 *
 * Description: Extended version of fstat supporting returning extended
 *              security information
 *
 * Parameters:  p                               The process doing the fstat
 *              uap->fd                         The fd to stat
 *              uap->ub                         The user stat buffer
 *              uap->xsecurity                  The user extended security
 *                                              buffer, or 0 if none
 *              uap->xsecurity_size             The size of xsecurity, or 0
 *
 * Returns:     0                               Success
 *              !0                              Errno (see fstat1)
 */
int
fstat_extended(proc_t p, struct fstat_extended_args *uap, __unused int32_t *retval)
{
        return(fstat1(p, uap->fd, uap->ub, uap->xsecurity, uap->xsecurity_size, 0));
}
 

/*
 * fstat
 *
 * Description: Get file status for the file associated with fd
 *
 * Parameters:  p                               The process doing the fstat
 *              uap->fd                         The fd to stat
 *              uap->ub                         The user stat buffer
 *
 * Returns:     0                               Success
 *              !0                              Errno (see fstat1)
 */
int
fstat(proc_t p, register struct fstat_args *uap, __unused int32_t *retval)
{
        return(fstat1(p, uap->fd, uap->ub, 0, 0, 0));
}


/*
 * fstat64_extended
 *
 * Description: Extended version of fstat64 supporting returning extended
 *              security information
 *
 * Parameters:  p                               The process doing the fstat
 *              uap->fd                         The fd to stat
 *              uap->ub                         The user stat buffer
 *              uap->xsecurity                  The user extended security
 *                                              buffer, or 0 if none
 *              uap->xsecurity_size             The size of xsecurity, or 0
 *
 * Returns:     0                               Success
 *              !0                              Errno (see fstat1)
 */
int
fstat64_extended(proc_t p, struct fstat64_extended_args *uap, __unused int32_t *retval)
{
        return(fstat1(p, uap->fd, uap->ub, uap->xsecurity, uap->xsecurity_size, 1));
}
 

/*
 * fstat64
 *
 * Description: Get 64 bit version of the file status for the file associated
 *              with fd
 *
 * Parameters:  p                               The process doing the fstat
 *              uap->fd                         The fd to stat
 *              uap->ub                         The user stat buffer
 *
 * Returns:     0                               Success
 *              !0                              Errno (see fstat1)
 */
int
fstat64(proc_t p, register struct fstat64_args *uap, __unused int32_t *retval)
{
        return(fstat1(p, uap->fd, uap->ub, 0, 0, 1));
}


/*
 * fpathconf
 *
 * Description: Return pathconf information about a file descriptor.
 *
 * Parameters:  p                               Process making the request
 *              uap->fd                         fd to get information about
 *              uap->name                       Name of information desired
 *              retval                          Pointer to the call return area
 *
 * Returns:     0                               Success
 *              EINVAL
 *      fp_lookup:EBADF                         Bad file descriptor
 *      vnode_getwithref:???
 *      vn_pathconf:???
 *
 * Implicit returns:
 *              *retval (modified)              Returned information (numeric)
 */
int
fpathconf(proc_t p, struct fpathconf_args *uap, int32_t *retval)
{
        int fd = uap->fd;
        struct fileproc *fp;
        struct vnode *vp;
        int error = 0;
        file_type_t type;
        caddr_t data;


        AUDIT_ARG(fd, uap->fd);
        if ( (error = fp_lookup(p, fd, &fp, 0)) )
                return(error);
        type = fp->f_type;
        data = fp->f_data;

        switch (type) {

        case DTYPE_SOCKET:
                if (uap->name != _PC_PIPE_BUF) {
                        error = EINVAL;
                        goto out;
                }
                *retval = PIPE_BUF;
                error = 0;
                goto out;

        case DTYPE_PIPE:
                if (uap->name != _PC_PIPE_BUF) {
                        error = EINVAL;
                        goto out;
                }
                *retval = PIPE_BUF;
                error = 0;
                goto out;

        case DTYPE_VNODE:
                vp = (struct vnode *)data;

                if ( (error = vnode_getwithref(vp)) == 0) {
                        AUDIT_ARG(vnpath, vp, ARG_VNODE1);

                        error = vn_pathconf(vp, uap->name, retval, vfs_context_current());

                        (void)vnode_put(vp);
                }
                goto out;

        case DTYPE_PSXSHM:
        case DTYPE_PSXSEM:
        case DTYPE_KQUEUE:
        case DTYPE_FSEVENTS:
                error = EINVAL;
                goto out;

        }
        /*NOTREACHED*/
out:
        fp_drop(p, fd, fp, 0);
        return(error);
}

/*
 * Statistics counter for the number of times a process calling fdalloc()
 * has resulted in an expansion of the per process open file table.
 *
 * XXX This would likely be of more use if it were per process
 */
int fdexpand;


/*
 * fdalloc
 *
 * Description: Allocate a file descriptor for the process.
 *
 * Parameters:  p                               Process to allocate the fd in
 *              want                            The fd we would prefer to get
 *              result                          Pointer to fd we got
 *
 * Returns:     0                               Success
 *              EMFILE
 *              ENOMEM
 *
 * Implicit returns:
 *              *result (modified)              The fd which was allocated
 */
int
fdalloc(proc_t p, int want, int *result)
{
        struct filedesc *fdp = p->p_fd;
        int i;
        int lim, last, numfiles, oldnfiles;
        struct fileproc **newofiles, **ofiles;
        char *newofileflags;

        /*
         * Search for a free descriptor starting at the higher
         * of want or fd_freefile.  If that fails, consider
         * expanding the ofile array.
         */
#if DIAGNOSTIC
        proc_fdlock_assert(p, LCK_MTX_ASSERT_OWNED);
#endif

        lim = min((int)p->p_rlimit[RLIMIT_NOFILE].rlim_cur, maxfiles);
        for (;;) {
                last = min(fdp->fd_nfiles, lim);
                if ((i = want) < fdp->fd_freefile)
                        i = fdp->fd_freefile;
                for (; i < last; i++) {
                        if (fdp->fd_ofiles[i] == NULL && !(fdp->fd_ofileflags[i] & UF_RESERVED)) {
                                procfdtbl_reservefd(p, i);
                                if (i > fdp->fd_lastfile)
                                        fdp->fd_lastfile = i;
                                if (want <= fdp->fd_freefile)
                                        fdp->fd_freefile = i;
                                *result = i;
                                return (0);
                        }
                }

                /*
                 * No space in current array.  Expand?
                 */
                if (fdp->fd_nfiles >= lim)
                        return (EMFILE);
                if (fdp->fd_nfiles < NDEXTENT)
                        numfiles = NDEXTENT;
                else
                        numfiles = 2 * fdp->fd_nfiles;
                /* Enforce lim */
                if (numfiles > lim)
                        numfiles = lim;
                proc_fdunlock(p);
                MALLOC_ZONE(newofiles, struct fileproc **,
                                numfiles * OFILESIZE, M_OFILETABL, M_WAITOK);
                proc_fdlock(p);
                if (newofiles == NULL) {
                        return (ENOMEM);
                }
                if (fdp->fd_nfiles >= numfiles) {
                        FREE_ZONE(newofiles, numfiles * OFILESIZE, M_OFILETABL);
                        continue;
                }
                newofileflags = (char *) &newofiles[numfiles];
                /*
                 * Copy the existing ofile and ofileflags arrays
                 * and zero the new portion of each array.
                 */
                oldnfiles = fdp->fd_nfiles;
                (void) memcpy(newofiles, fdp->fd_ofiles,
                                oldnfiles * sizeof(*fdp->fd_ofiles));
                (void) memset(&newofiles[oldnfiles], 0,
                                (numfiles - oldnfiles) * sizeof(*fdp->fd_ofiles));

                (void) memcpy(newofileflags, fdp->fd_ofileflags,
                                oldnfiles * sizeof(*fdp->fd_ofileflags));
                (void) memset(&newofileflags[oldnfiles], 0,
                                (numfiles - oldnfiles) *
                                                sizeof(*fdp->fd_ofileflags));
                ofiles = fdp->fd_ofiles;
                fdp->fd_ofiles = newofiles;
                fdp->fd_ofileflags = newofileflags;
                fdp->fd_nfiles = numfiles;
                FREE_ZONE(ofiles, oldnfiles * OFILESIZE, M_OFILETABL);
                fdexpand++;
        }
}


/*
 * fdavail
 *
 * Description: Check to see whether n user file descriptors are available
 *              to the process p.
 *
 * Parameters:  p                               Process to check in
 *              n                               The number of fd's desired
 *
 * Returns:     0                               No
 *              1                               Yes
 *
 * Locks:       Assumes proc_fdlock for process is held by the caller
 *
 * Notes:       The answer only remains valid so long as the proc_fdlock is
 *              held by the caller.
 */
int
fdavail(proc_t p, int n)
{
        struct filedesc *fdp = p->p_fd;
        struct fileproc **fpp;
        char *flags;
        int i, lim;

        lim = min((int)p->p_rlimit[RLIMIT_NOFILE].rlim_cur, maxfiles);
        if ((i = lim - fdp->fd_nfiles) > 0 && (n -= i) <= 0)
                return (1);
        fpp = &fdp->fd_ofiles[fdp->fd_freefile];
        flags = &fdp->fd_ofileflags[fdp->fd_freefile];
        for (i = fdp->fd_nfiles - fdp->fd_freefile; --i >= 0; fpp++, flags++)
                if (*fpp == NULL && !(*flags & UF_RESERVED) && --n <= 0)
                        return (1);
        return (0);
}


/*
 * fdrelse
 *
 * Description: Legacy KPI wrapper function for _fdrelse
 *
 * Parameters:  p                               Process in which fd lives
 *              fd                              fd to free
 *
 * Returns:     void
 *
 * Locks:       Assumes proc_fdlock for process is held by the caller
 */
void
fdrelse(proc_t p, int fd)
{
        _fdrelse(p, fd);
}


/*
 * fdgetf_noref
 *
 * Description: Get the fileproc pointer for the given fd from the per process
 *              open file table without taking an explicit reference on it.
 *
 * Parameters:  p                               Process containing fd
 *              fd                              fd to obtain fileproc for
 *              resultfp                        Pointer to pointer return area
 *
 * Returns:     0                               Success
 *              EBADF
 *
 * Implicit returns:
 *              *resultfp (modified)            Pointer to fileproc pointer
 *
 * Locks:       Assumes proc_fdlock for process is held by the caller
 *
 * Notes:       Because there is no reference explicitly taken, the returned
 *              fileproc pointer is only valid so long as the proc_fdlock
 *              remains held by the caller.
 */
int
fdgetf_noref(proc_t p, int fd, struct fileproc **resultfp)
{
        struct filedesc *fdp = p->p_fd;
        struct fileproc *fp;

        if (fd < 0 || fd >= fdp->fd_nfiles ||
                        (fp = fdp->fd_ofiles[fd]) == NULL ||
                        (fdp->fd_ofileflags[fd] & UF_RESERVED)) {
                return (EBADF);
        }
        if (resultfp)
                *resultfp = fp;
        return (0);
}


/*
 * fp_getfvp
 *
 * Description: Get fileproc and vnode pointer for a given fd from the per
 *              process open file table of the specified process, and if
 *              successful, increment the f_iocount
 *
 * Parameters:  p                               Process in which fd lives
 *              fd                              fd to get information for
 *              resultfp                        Pointer to result fileproc
 *                                              pointer area, or 0 if none
 *              resultvp                        Pointer to result vnode pointer
 *                                              area, or 0 if none
 *
 * Returns:     0                               Success
 *              EBADF                           Bad file descriptor
 *              ENOTSUP                         fd does not refer to a vnode
 *
 * Implicit returns:
 *              *resultfp (modified)            Fileproc pointer
 *              *resultvp (modified)            vnode pointer
 *
 * Notes:       The resultfp and resultvp fields are optional, and may be
 *              independently specified as NULL to skip returning information
 *
 * Locks:       Internally takes and releases proc_fdlock
 */
int
fp_getfvp(proc_t p, int fd, struct fileproc **resultfp, struct vnode **resultvp)
{
        struct filedesc *fdp = p->p_fd;
        struct fileproc *fp;

        proc_fdlock_spin(p);
        if (fd < 0 || fd >= fdp->fd_nfiles ||
                        (fp = fdp->fd_ofiles[fd]) == NULL ||
                        (fdp->fd_ofileflags[fd] & UF_RESERVED)) {
                proc_fdunlock(p);
                return (EBADF);
        }
        if (fp->f_type != DTYPE_VNODE) {
                proc_fdunlock(p);
                return(ENOTSUP);
        }
        fp->f_iocount++;

        if (resultfp)
                *resultfp = fp;
        if (resultvp)
                *resultvp = (struct vnode *)fp->f_data;
        proc_fdunlock(p);

        return (0);
}


/*
 * fp_getfvpandvid
 *
 * Description: Get fileproc, vnode pointer, and vid for a given fd from the
 *              per process open file table of the specified process, and if
 *              successful, increment the f_iocount
 *
 * Parameters:  p                               Process in which fd lives
 *              fd                              fd to get information for
 *              resultfp                        Pointer to result fileproc
 *                                              pointer area, or 0 if none
 *              resultvp                        Pointer to result vnode pointer
 *                                              area, or 0 if none
 *              vidp                            Pointer to resuld vid area
 *
 * Returns:     0                               Success
 *              EBADF                           Bad file descriptor
 *              ENOTSUP                         fd does not refer to a vnode
 *
 * Implicit returns:
 *              *resultfp (modified)            Fileproc pointer
 *              *resultvp (modified)            vnode pointer
 *              *vidp                           vid value
 *
 * Notes:       The resultfp and resultvp fields are optional, and may be
 *              independently specified as NULL to skip returning information
 *
 * Locks:       Internally takes and releases proc_fdlock
 */
int
fp_getfvpandvid(proc_t p, int fd, struct fileproc **resultfp,
                struct vnode **resultvp, uint32_t *vidp)
{
        struct filedesc *fdp = p->p_fd;
        struct fileproc *fp;

        proc_fdlock_spin(p);
        if (fd < 0 || fd >= fdp->fd_nfiles ||
                        (fp = fdp->fd_ofiles[fd]) == NULL ||
                        (fdp->fd_ofileflags[fd] & UF_RESERVED)) {
                proc_fdunlock(p);
                return (EBADF);
        }
        if (fp->f_type != DTYPE_VNODE) {
                proc_fdunlock(p);
                return(ENOTSUP);
        }
        fp->f_iocount++;

        if (resultfp)
                *resultfp = fp;
        if (resultvp)
                *resultvp = (struct vnode *)fp->f_data;
        if (vidp)
                *vidp = (uint32_t)vnode_vid((struct vnode *)fp->f_data);
        proc_fdunlock(p);

        return (0);
}


/*
 * fp_getfsock
 *
 * Description: Get fileproc and socket pointer for a given fd from the
 *              per process open file table of the specified process, and if
 *              successful, increment the f_iocount
 *
 * Parameters:  p                               Process in which fd lives
 *              fd                              fd to get information for
 *              resultfp                        Pointer to result fileproc
 *                                              pointer area, or 0 if none
 *              results                         Pointer to result socket
 *                                              pointer area, or 0 if none
 *
 * Returns:     EBADF                   The file descriptor is invalid
 *              EOPNOTSUPP              The file descriptor is not a socket
 *              0                       Success
 *
 * Implicit returns:
 *              *resultfp (modified)            Fileproc pointer
 *              *results (modified)             socket pointer
 *
 * Notes:       EOPNOTSUPP should probably be ENOTSOCK; this function is only
 *              ever called from accept1().
 */
int
fp_getfsock(proc_t p, int fd, struct fileproc **resultfp,
            struct socket **results)
{
        struct filedesc *fdp = p->p_fd;
        struct fileproc *fp;

        proc_fdlock_spin(p);
        if (fd < 0 || fd >= fdp->fd_nfiles ||
                        (fp = fdp->fd_ofiles[fd]) == NULL ||
                        (fdp->fd_ofileflags[fd] & UF_RESERVED)) {
                proc_fdunlock(p);
                return (EBADF);
        }
        if (fp->f_type != DTYPE_SOCKET) {
                proc_fdunlock(p);
                return(EOPNOTSUPP);
        }
        fp->f_iocount++;

        if (resultfp)
                *resultfp = fp;
        if (results)
                *results = (struct socket *)fp->f_data;
        proc_fdunlock(p);

        return (0);
}


/*
 * fp_getfkq
 *
 * Description: Get fileproc and kqueue pointer for a given fd from the
 *              per process open file table of the specified process, and if
 *              successful, increment the f_iocount
 *
 * Parameters:  p                               Process in which fd lives
 *              fd                              fd to get information for
 *              resultfp                        Pointer to result fileproc
 *                                              pointer area, or 0 if none
 *              resultkq                        Pointer to result kqueue
 *                                              pointer area, or 0 if none
 *
 * Returns:     EBADF                   The file descriptor is invalid
 *              EBADF                   The file descriptor is not a socket
 *              0                       Success
 *
 * Implicit returns:
 *              *resultfp (modified)            Fileproc pointer
 *              *resultkq (modified)            kqueue pointer
 *
 * Notes:       The second EBADF should probably be something else to make
 *              the error condition distinct.
 */
int
fp_getfkq(proc_t p, int fd, struct fileproc **resultfp,
          struct kqueue **resultkq)
{
        struct filedesc *fdp = p->p_fd;
        struct fileproc *fp;

        proc_fdlock_spin(p);
        if ( fd < 0 || fd >= fdp->fd_nfiles ||
                        (fp = fdp->fd_ofiles[fd]) == NULL ||
                        (fdp->fd_ofileflags[fd] & UF_RESERVED)) {
                proc_fdunlock(p);
                return (EBADF);
        }
        if (fp->f_type != DTYPE_KQUEUE) {
                proc_fdunlock(p);
                return(EBADF);
        }
        fp->f_iocount++;

        if (resultfp)
                *resultfp = fp;
        if (resultkq)
                *resultkq = (struct kqueue *)fp->f_data;
        proc_fdunlock(p);

        return (0);
}


/*
 * fp_getfpshm
 *
 * Description: Get fileproc and POSIX shared memory pointer for a given fd
 *              from the per process open file table of the specified process
 *              and if successful, increment the f_iocount
 *
 * Parameters:  p                               Process in which fd lives
 *              fd                              fd to get information for
 *              resultfp                        Pointer to result fileproc
 *                                              pointer area, or 0 if none
 *              resultpshm                      Pointer to result POSIX
 *                                              shared memory pointer
 *                                              pointer area, or 0 if none
 *
 * Returns:     EBADF                   The file descriptor is invalid
 *              EBADF                   The file descriptor is not a POSIX
 *                                      shared memory area
 *              0                       Success
 *
 * Implicit returns:
 *              *resultfp (modified)            Fileproc pointer
 *              *resultpshm (modified)          POSIX shared memory pointer
 *
 * Notes:       The second EBADF should probably be something else to make
 *              the error condition distinct.
 */
int
fp_getfpshm(proc_t p, int fd, struct fileproc **resultfp,
            struct pshmnode **resultpshm)
{
        struct filedesc *fdp = p->p_fd;
        struct fileproc *fp;

        proc_fdlock_spin(p);
        if (fd < 0 || fd >= fdp->fd_nfiles ||
                        (fp = fdp->fd_ofiles[fd]) == NULL ||
                        (fdp->fd_ofileflags[fd] & UF_RESERVED)) {
                proc_fdunlock(p);
                return (EBADF);
        }
        if (fp->f_type != DTYPE_PSXSHM) {

                proc_fdunlock(p);
                return(EBADF);
        }
        fp->f_iocount++;

        if (resultfp)
                *resultfp = fp;
        if (resultpshm)
                *resultpshm = (struct pshmnode *)fp->f_data;
        proc_fdunlock(p);

        return (0);
}


/*
 * fp_getfsem
 *
 * Description: Get fileproc and POSIX semaphore pointer for a given fd from
 *              the per process open file table of the specified process
 *              and if successful, increment the f_iocount
 *
 * Parameters:  p                               Process in which fd lives
 *              fd                              fd to get information for
 *              resultfp                        Pointer to result fileproc
 *                                              pointer area, or 0 if none
 *              resultpsem                      Pointer to result POSIX
 *                                              semaphore pointer area, or
 *                                              0 if none
 *
 * Returns:     EBADF                   The file descriptor is invalid
 *              EBADF                   The file descriptor is not a POSIX
 *                                      semaphore
 *              0                       Success
 *
 * Implicit returns:
 *              *resultfp (modified)            Fileproc pointer
 *              *resultpsem (modified)          POSIX semaphore pointer
 *
 * Notes:       The second EBADF should probably be something else to make
 *              the error condition distinct.
 *
 *              In order to support unnamed POSIX semaphores, the named
 *              POSIX semaphores will have to move out of the per-process
 *              open filetable, and into a global table that is shared with
 *              unnamed POSIX semaphores, since unnamed POSIX semaphores
 *              are typically used by declaring instances in shared memory,
 *              and there's no other way to do this without changing the
 *              underlying type, which would introduce binary compatibility
 *              issues.
 */
int
fp_getfpsem(proc_t p, int fd, struct fileproc **resultfp,
            struct psemnode **resultpsem)
{
        struct filedesc *fdp = p->p_fd;
        struct fileproc *fp;

        proc_fdlock_spin(p);
        if (fd < 0 || fd >= fdp->fd_nfiles ||
                        (fp = fdp->fd_ofiles[fd]) == NULL ||
                        (fdp->fd_ofileflags[fd] & UF_RESERVED)) {
                proc_fdunlock(p);
                return (EBADF);
        }
        if (fp->f_type != DTYPE_PSXSEM) {
                proc_fdunlock(p);
                return(EBADF);
        }
        fp->f_iocount++;

        if (resultfp)
                *resultfp = fp;
        if (resultpsem)
                *resultpsem = (struct psemnode *)fp->f_data;
        proc_fdunlock(p);

        return (0);
}


/*
 * fp_getfpipe
 *
 * Description: Get fileproc and pipe pointer for a given fd from the
 *              per process open file table of the specified process
 *              and if successful, increment the f_iocount
 *
 * Parameters:  p                               Process in which fd lives
 *              fd                              fd to get information for
 *              resultfp                        Pointer to result fileproc
 *                                              pointer area, or 0 if none
 *              resultpipe                      Pointer to result pipe
 *                                              pointer area, or 0 if none
 *
 * Returns:     EBADF                   The file descriptor is invalid
 *              EBADF                   The file descriptor is not a socket
 *              0                       Success
 *
 * Implicit returns:
 *              *resultfp (modified)            Fileproc pointer
 *              *resultpipe (modified)          pipe pointer
 *
 * Notes:       The second EBADF should probably be something else to make
 *              the error condition distinct.
 */
int
fp_getfpipe(proc_t p, int fd, struct fileproc **resultfp,
            struct pipe **resultpipe)
{
        struct filedesc *fdp = p->p_fd;
        struct fileproc *fp;

        proc_fdlock_spin(p);
        if (fd < 0 || fd >= fdp->fd_nfiles ||
                        (fp = fdp->fd_ofiles[fd]) == NULL ||
                        (fdp->fd_ofileflags[fd] & UF_RESERVED)) {
                proc_fdunlock(p);
                return (EBADF);
        }
        if (fp->f_type != DTYPE_PIPE) {
                proc_fdunlock(p);
                return(EBADF);
        }
        fp->f_iocount++;

        if (resultfp)
                *resultfp = fp;
        if (resultpipe)
                *resultpipe = (struct pipe *)fp->f_data;
        proc_fdunlock(p);

        return (0);
}

#if NETAT
#define DTYPE_ATALK -1          /* XXX This does not belong here */


/*
 * fp_getfatalk
 *
 * Description: Get fileproc and atalk pointer for a given fd from the
 *              per process open file table of the specified process
 *              and if successful, increment the f_iocount
 *
 * Parameters:  p                               Process in which fd lives
 *              fd                              fd to get information for
 *              resultfp                        Pointer to result fileproc
 *                                              pointer area, or 0 if none
 *              resultatalk                     Pointer to result atalk
 *                                              pointer area, or 0 if none
 * Returns:     EBADF                   The file descriptor is invalid
 *              EBADF                   The file descriptor is not a socket
 *              0                       Success
 *
 * Implicit returns:
 *              *resultfp (modified)            Fileproc pointer
 *              *resultatalk (modified)         atalk pointer
 *
 * Notes:       The second EBADF should probably be something else to make
 *              the error condition distinct.
 *
 *              XXX This code is specific to AppleTalk protocol support, and
 *              XXX should be conditionally compiled
 */
int
fp_getfatalk(proc_t p, int fd, struct fileproc **resultfp,
             struct atalk **resultatalk)
{
        struct filedesc *fdp = p->p_fd;
        struct fileproc *fp;

        proc_fdlock_spin(p);
        if (fd < 0 || fd >= fdp->fd_nfiles ||
                        (fp = fdp->fd_ofiles[fd]) == NULL ||
                        (fdp->fd_ofileflags[fd] & UF_RESERVED)) {
                proc_fdunlock(p);
                return (EBADF);
        }
        if (fp->f_type != (DTYPE_ATALK+1)) {
                proc_fdunlock(p);
                return(EBADF);
        }
        fp->f_iocount++;

        if (resultfp)
                *resultfp = fp;
        if (resultatalk)
                *resultatalk = (struct atalk *)fp->f_data;
        proc_fdunlock(p);

        return (0);
}

#endif /* NETAT */

/*
 * fp_lookup
 *
 * Description: Get fileproc pointer for a given fd from the per process
 *              open file table of the specified process and if successful,
 *              increment the f_iocount
 *
 * Parameters:  p                               Process in which fd lives
 *              fd                              fd to get information for
 *              resultfp                        Pointer to result fileproc
 *                                              pointer area, or 0 if none
 *              locked                          !0 if the caller holds the
 *                                              proc_fdlock, 0 otherwise
 *
 * Returns:     0                       Success
 *              EBADF                   Bad file descriptor
 *
 * Implicit returns:
 *              *resultfp (modified)            Fileproc pointer
 *
 * Locks:       If the argument 'locked' is non-zero, then the caller is
 *              expected to have taken and held the proc_fdlock; if it is
 *              zero, than this routine internally takes and drops this lock.
 */
int
fp_lookup(proc_t p, int fd, struct fileproc **resultfp, int locked)
{
        struct filedesc *fdp = p->p_fd;
        struct fileproc *fp;

        if (!locked)
                proc_fdlock_spin(p);
        if (fd < 0 || fdp == NULL || fd >= fdp->fd_nfiles ||
                        (fp = fdp->fd_ofiles[fd]) == NULL ||
                        (fdp->fd_ofileflags[fd] & UF_RESERVED)) {
                if (!locked)
                        proc_fdunlock(p);
                return (EBADF);
        }
        fp->f_iocount++;

        if (resultfp)
                *resultfp = fp;
        if (!locked)
                proc_fdunlock(p);
                
        return (0);
}


/*
 * fp_drop_written
 *
 * Description: Set the FP_WRITTEN flag on the fileproc and drop the I/O
 *              reference previously taken by calling fp_lookup et. al.
 *
 * Parameters:  p                               Process in which the fd lives
 *              fd                              fd associated with the fileproc
 *              fp                              fileproc on which to set the
 *                                              flag and drop the reference
 *
 * Returns:     0                               Success
 *      fp_drop:EBADF                           Bad file descriptor
 *
 * Locks:       This function internally takes and drops the proc_fdlock for
 *              the supplied process
 *
 * Notes:       The fileproc must correspond to the fd in the supplied proc
 */
int
fp_drop_written(proc_t p, int fd, struct fileproc *fp)
{
        int error;

        proc_fdlock_spin(p);

        fp->f_flags |= FP_WRITTEN;
        
        error = fp_drop(p, fd, fp, 1);

        proc_fdunlock(p);
                
        return (error);
}


/*
 * fp_drop_event
 *
 * Description: Set the FP_WAITEVENT flag on the fileproc and drop the I/O
 *              reference previously taken by calling fp_lookup et. al.
 *
 * Parameters:  p                               Process in which the fd lives
 *              fd                              fd associated with the fileproc
 *              fp                              fileproc on which to set the
 *                                              flag and drop the reference
 *
 * Returns:     0                               Success
 *      fp_drop:EBADF                           Bad file descriptor
 *
 * Locks:       This function internally takes and drops the proc_fdlock for
 *              the supplied process
 *
 * Notes:       The fileproc must correspond to the fd in the supplied proc
 */
int
fp_drop_event(proc_t p, int fd, struct fileproc *fp)
{
        int error;

        proc_fdlock_spin(p);

        fp->f_flags |= FP_WAITEVENT;
        
        error = fp_drop(p, fd, fp, 1);

        proc_fdunlock(p);
                
        return (error);
}


/*
 * fp_drop
 *
 * Description: Drop the I/O reference previously taken by calling fp_lookup
 *              et. al.
 *
 * Parameters:  p                               Process in which the fd lives
 *              fd                              fd associated with the fileproc
 *              fp                              fileproc on which to set the
 *                                              flag and drop the reference
 *              locked                          flag to internally take and
 *                                              drop proc_fdlock if it is not
 *                                              already held by the caller
 *
 * Returns:     0                               Success
 *              EBADF                           Bad file descriptor
 *
 * Locks:       This function internally takes and drops the proc_fdlock for
 *              the supplied process if 'locked' is non-zero, and assumes that
 *              the caller already holds this lock if 'locked' is non-zero.
 *
 * Notes:       The fileproc must correspond to the fd in the supplied proc
 */
int
fp_drop(proc_t p, int fd, struct fileproc *fp, int locked)
{
        struct filedesc *fdp = p->p_fd;
        int     needwakeup = 0;

        if (!locked)
                proc_fdlock_spin(p);
         if ((fp == FILEPROC_NULL) && (fd < 0 || fd >= fdp->fd_nfiles ||
                        (fp = fdp->fd_ofiles[fd]) == NULL ||
                        ((fdp->fd_ofileflags[fd] & UF_RESERVED) &&
                         !(fdp->fd_ofileflags[fd] & UF_CLOSING)))) {
                if (!locked)
                        proc_fdunlock(p);
                return (EBADF);
        }
        fp->f_iocount--;

        if (fp->f_iocount == 0) {
                if (fp->f_flags & FP_SELCONFLICT)
                        fp->f_flags &= ~FP_SELCONFLICT;

                if (p->p_fpdrainwait) {
                        p->p_fpdrainwait = 0;
                        needwakeup = 1;
                }
        }
        if (!locked)
                proc_fdunlock(p);
        if (needwakeup)
                wakeup(&p->p_fpdrainwait);
                
        return (0);
}


/*
 * file_vnode
 *
 * Description: Given an fd, look it up in the current process's per process
 *              open file table, and return its internal vnode pointer.
 *
 * Parameters:  fd                              fd to obtain vnode from
 *              vpp                             pointer to vnode return area
 *
 * Returns:     0                               Success
 *              EINVAL                          The fd does not refer to a
 *                                              vnode fileproc entry
 *      fp_lookup:EBADF                         Bad file descriptor
 *
 * Implicit returns:
 *              *vpp (modified)                 Returned vnode pointer
 *
 * Locks:       This function internally takes and drops the proc_fdlock for
 *              the current process
 *
 * Notes:       If successful, this function increments the f_iocount on the
 *              fd's corresponding fileproc.
 *
 *              The fileproc referenced is not returned; because of this, care
 *              must be taken to not drop the last reference (e.g. by closing
 *              the file).  This is inherently unsafe, since the reference may
 *              not be recoverable from the vnode, if there is a subsequent
 *              close that destroys the associate fileproc.  The caller should
 *              therefore retain their own reference on the fileproc so that
 *              the f_iocount can be dropped subsequently.  Failure to do this
 *              can result in the returned pointer immediately becoming invalid
 *              following the call.
 *
 *              Use of this function is discouraged.
 */
int
file_vnode(int fd, struct vnode **vpp)
{
        proc_t p = current_proc();
        struct fileproc *fp;
        int error;
        
        proc_fdlock_spin(p);
        if ( (error = fp_lookup(p, fd, &fp, 1)) ) {
                proc_fdunlock(p);
                return(error);
        }
        if (fp->f_type != DTYPE_VNODE) {
                fp_drop(p, fd, fp,1);
                proc_fdunlock(p);
                return(EINVAL);
        }
        if (vpp != NULL)
                *vpp = (struct vnode *)fp->f_data;
        proc_fdunlock(p);

        return(0);
}


/*
 * file_vnode_withvid
 *
 * Description: Given an fd, look it up in the current process's per process
 *              open file table, and return its internal vnode pointer.
 *
 * Parameters:  fd                              fd to obtain vnode from
 *              vpp                             pointer to vnode return area
 *              vidp                            pointer to vid of the returned vnode
 *
 * Returns:     0                               Success
 *              EINVAL                          The fd does not refer to a
 *                                              vnode fileproc entry
 *      fp_lookup:EBADF                         Bad file descriptor
 *
 * Implicit returns:
 *              *vpp (modified)                 Returned vnode pointer
 *
 * Locks:       This function internally takes and drops the proc_fdlock for
 *              the current process
 *
 * Notes:       If successful, this function increments the f_iocount on the
 *              fd's corresponding fileproc.
 *
 *              The fileproc referenced is not returned; because of this, care
 *              must be taken to not drop the last reference (e.g. by closing
 *              the file).  This is inherently unsafe, since the reference may
 *              not be recoverable from the vnode, if there is a subsequent
 *              close that destroys the associate fileproc.  The caller should
 *              therefore retain their own reference on the fileproc so that
 *              the f_iocount can be dropped subsequently.  Failure to do this
 *              can result in the returned pointer immediately becoming invalid
 *              following the call.
 *
 *              Use of this function is discouraged.
 */
int
file_vnode_withvid(int fd, struct vnode **vpp, uint32_t * vidp)
{
        proc_t p = current_proc();
        struct fileproc *fp;
        vnode_t vp;
        int error;
        
        proc_fdlock_spin(p);
        if ( (error = fp_lookup(p, fd, &fp, 1)) ) {
                proc_fdunlock(p);
                return(error);
        }
        if (fp->f_type != DTYPE_VNODE) {
                fp_drop(p, fd, fp,1);
                proc_fdunlock(p);
                return(EINVAL);
        }
        vp = (struct vnode *)fp->f_data;
        if (vpp != NULL) 
                *vpp = vp;

        if ((vidp != NULL) && (vp != NULLVP)) 
                *vidp = (uint32_t)vp->v_id;

        proc_fdunlock(p);

        return(0);
}


/*
 * file_socket
 *
 * Description: Given an fd, look it up in the current process's per process
 *              open file table, and return its internal socket pointer.
 *
 * Parameters:  fd                              fd to obtain vnode from
 *              sp                              pointer to socket return area
 *
 * Returns:     0                               Success
 *              ENOTSOCK                        Not a socket
 *              fp_lookup:EBADF                 Bad file descriptor
 *
 * Implicit returns:
 *              *sp (modified)                  Returned socket pointer
 *
 * Locks:       This function internally takes and drops the proc_fdlock for
 *              the current process
 *
 * Notes:       If successful, this function increments the f_iocount on the
 *              fd's corresponding fileproc.
 *
 *              The fileproc referenced is not returned; because of this, care
 *              must be taken to not drop the last reference (e.g. by closing
 *              the file).  This is inherently unsafe, since the reference may
 *              not be recoverable from the socket, if there is a subsequent
 *              close that destroys the associate fileproc.  The caller should
 *              therefore retain their own reference on the fileproc so that
 *              the f_iocount can be dropped subsequently.  Failure to do this
 *              can result in the returned pointer immediately becoming invalid
 *              following the call.
 *
 *              Use of this function is discouraged.
 */
int
file_socket(int fd, struct socket **sp)
{
        proc_t p = current_proc();
        struct fileproc *fp;
        int error;
        
        proc_fdlock_spin(p);
        if ( (error = fp_lookup(p, fd, &fp, 1)) ) {
                proc_fdunlock(p);
                return(error);
        }
        if (fp->f_type != DTYPE_SOCKET) {
                fp_drop(p, fd, fp,1);
                proc_fdunlock(p);
                return(ENOTSOCK);
        }
        *sp = (struct socket *)fp->f_data;
        proc_fdunlock(p);

        return(0);
}


/*
 * file_flags
 *
 * Description: Given an fd, look it up in the current process's per process
 *              open file table, and return its fileproc's flags field.
 *
 * Parameters:  fd                              fd whose flags are to be
 *                                              retrieved
 *              flags                           pointer to flags data area
 *
 * Returns:     0                               Success
 *              ENOTSOCK                        Not a socket
 *              fp_lookup:EBADF                 Bad file descriptor
 *
 * Implicit returns:
 *              *flags (modified)               Returned flags field
 *
 * Locks:       This function internally takes and drops the proc_fdlock for
 *              the current process
 *
 * Notes:       This function will internally increment and decrement the
 *              f_iocount of the fileproc as part of its operation.
 */
int
file_flags(int fd, int *flags)
{

        proc_t p = current_proc();
        struct fileproc *fp;
        int error;
        
        proc_fdlock_spin(p);
        if ( (error = fp_lookup(p, fd, &fp, 1)) ) {
                proc_fdunlock(p);
                return(error);
        }
        *flags = (int)fp->f_flag;
        fp_drop(p, fd, fp,1);
        proc_fdunlock(p);

        return(0);
}


/*
 * file_drop
 *
 * Description: Drop an iocount reference on an fd, and wake up any waiters
 *              for draining (i.e. blocked in fileproc_drain() called during
 *              the last attempt to close a file).
 *
 * Parameters:  fd                              fd on which an ioreference is
 *                                              to be dropped
 *
 * Returns:     0                               Success
 *              EBADF                           Bad file descriptor
 *
 * Description: Given an fd, look it up in the current process's per process
 *              open file table, and drop it's fileproc's f_iocount by one
 *
 * Notes:       This is intended as a corresponding operation to the functions
 *              file_vnode() and file_socket() operations.
 *
 *              Technically, the close reference is supposed to be protected
 *              by a fileproc_drain(), however, a drain will only block if
 *              the fd refers to a character device, and that device has had
 *              preparefileread() called on it.  If it refers to something
 *              other than a character device, then the drain will occur and
 *              block each close attempt, rather than merely the last close.
 *
 *              Since it's possible for an fd that refers to a character
 *              device to have an intermediate close followed by an open to
 *              cause a different file to correspond to that descriptor,
 *              unless there was a cautionary reference taken on the fileproc,
 *              this is an inherently unsafe function.  This happens in the
 *              case where multiple fd's in a process refer to the same
 *              character device (e.g. stdin/out/err pointing to a tty, etc.).
 *
 *              Use of this function is discouraged.
 */
int 
file_drop(int fd)
{
        struct fileproc *fp;
        proc_t p = current_proc();
        int     needwakeup = 0;

        proc_fdlock_spin(p);
        if (fd < 0 || fd >= p->p_fd->fd_nfiles ||
                        (fp = p->p_fd->fd_ofiles[fd]) == NULL ||
                        ((p->p_fd->fd_ofileflags[fd] & UF_RESERVED) &&
                         !(p->p_fd->fd_ofileflags[fd] & UF_CLOSING))) {
                proc_fdunlock(p);
                return (EBADF);
        }
        fp->f_iocount --;

        if (fp->f_iocount == 0) {
                if (fp->f_flags & FP_SELCONFLICT)
                        fp->f_flags &= ~FP_SELCONFLICT;

                if (p->p_fpdrainwait) {
                        p->p_fpdrainwait = 0;
                        needwakeup = 1;
                }
        }
        proc_fdunlock(p);

        if (needwakeup)
                wakeup(&p->p_fpdrainwait);
        return(0);
}


/*
 * falloc
 *
 * Description: Allocate an entry in the per process open file table and
 *              return the corresponding fileproc and fd.
 *
 * Parameters:  p                               The process in whose open file
 *                                              table the fd is to be allocated
 *              resultfp                        Pointer to fileproc pointer
 *                                              return area
 *              resultfd                        Pointer to fd return area
 *              ctx                             VFS context
 *
 * Returns:     0                               Success
 *      falloc:ENFILE                           Too many open files in system
 *      falloc:EMFILE                           Too many open files in process
 *      falloc:ENOMEM                           M_FILEPROC or M_FILEGLOB zone
 *                                              exhausted
 *
 * Implicit returns:
 *              *resultfd (modified)            Returned fileproc pointer
 *              *resultfd (modified)            Returned fd
 *
 * Locks:       This function takes and drops the proc_fdlock; if this lock
 *              is already held, use falloc_locked() instead.
 *
 * Notes:       This function takes separate process and context arguments
 *              solely to support kern_exec.c; otherwise, it would take
 *              neither, and expect falloc_locked() to use the
 *              vfs_context_current() routine internally.
 */
int
falloc(proc_t p, struct fileproc **resultfp, int *resultfd, vfs_context_t ctx)
{
        int error;

        proc_fdlock(p);
        error = falloc_locked(p, resultfp, resultfd, ctx, 1);
        proc_fdunlock(p);

        return(error);
}


/*
 * falloc_locked
 *
 * Create a new open file structure and allocate
 * a file descriptor for the process that refers to it.
 *
 * Returns:     0                       Success
 *
 * Description: Allocate an entry in the per process open file table and
 *              return the corresponding fileproc and fd.
 *
 * Parameters:  p                               The process in whose open file
 *                                              table the fd is to be allocated
 *              resultfp                        Pointer to fileproc pointer
 *                                              return area
 *              resultfd                        Pointer to fd return area
 *              ctx                             VFS context
 *              locked                          Flag to indicate whether the
 *                                              caller holds proc_fdlock
 *
 * Returns:     0                               Success
 *              ENFILE                          Too many open files in system
 *              fdalloc:EMFILE                  Too many open files in process
 *              ENOMEM                          M_FILEPROC or M_FILEGLOB zone
 *                                              exhausted
 *      fdalloc:ENOMEM
 *
 * Implicit returns:
 *              *resultfd (modified)            Returned fileproc pointer
 *              *resultfd (modified)            Returned fd
 *
 * Locks:       If the parameter 'locked' is zero, this function takes and
 *              drops the proc_fdlock; if non-zero, the caller must hold the
 *              lock.
 *
 * Notes:       If you intend to use a non-zero 'locked' parameter, use the
 *              utility function falloc() instead.
 *
 *              This function takes separate process and context arguments
 *              solely to support kern_exec.c; otherwise, it would take
 *              neither, and use the vfs_context_current() routine internally.
 */
int
falloc_locked(proc_t p, struct fileproc **resultfp, int *resultfd,
              vfs_context_t ctx, int locked)
{
        struct fileproc *fp, *fq;
        struct fileglob *fg;
        int error, nfd;

        if (!locked)
                proc_fdlock(p);
        if ( (error = fdalloc(p, 0, &nfd)) ) {
                if (!locked)
                        proc_fdunlock(p);
                return (error);
        }
        if (nfiles >= maxfiles) {
                if (!locked)
                        proc_fdunlock(p);
                tablefull("file");
                return (ENFILE);
        }
#if CONFIG_MACF
        error = mac_file_check_create(proc_ucred(p));
        if (error) {
                if (!locked)
                        proc_fdunlock(p);
                return (error);
        }
#endif

        /*
         * Allocate a new file descriptor.
         * If the process has file descriptor zero open, add to the list
         * of open files at that point, otherwise put it at the front of
         * the list of open files.
         */
        proc_fdunlock(p);

        MALLOC_ZONE(fp, struct fileproc *, sizeof(struct fileproc), M_FILEPROC, M_WAITOK);
        if (fp == NULL) {
                if (locked)
                        proc_fdlock(p);
                return (ENOMEM);
        }
        MALLOC_ZONE(fg, struct fileglob *, sizeof(struct fileglob), M_FILEGLOB, M_WAITOK);
        if (fg == NULL) {
                FREE_ZONE(fp, sizeof(*fp), M_FILEPROC);
                if (locked)
                        proc_fdlock(p);
                return (ENOMEM);
        }
        bzero(fp, sizeof(struct fileproc));
        bzero(fg, sizeof(struct fileglob));
        lck_mtx_init(&fg->fg_lock, file_lck_grp, file_lck_attr);

        fp->f_iocount = 1;
        fg->fg_count = 1;
        fp->f_fglob = fg;
#if CONFIG_MACF
        mac_file_label_init(fg);
#endif

        kauth_cred_ref(ctx->vc_ucred);

        proc_fdlock(p);

        fp->f_cred = ctx->vc_ucred;

#if CONFIG_MACF
        mac_file_label_associate(fp->f_cred, fg);
#endif

        lck_mtx_lock_spin(file_flist_lock);

        nfiles++;

        if ( (fq = p->p_fd->fd_ofiles[0]) ) {
                LIST_INSERT_AFTER(fq->f_fglob, fg, f_list);
        } else {
                LIST_INSERT_HEAD(&filehead, fg, f_list);
        }
        lck_mtx_unlock(file_flist_lock);

        p->p_fd->fd_ofiles[nfd] = fp;

        if (!locked)
                proc_fdunlock(p);

        if (resultfp)
                *resultfp = fp;
        if (resultfd)
                *resultfd = nfd;

        return (0);
}


/*
 * fg_free
 *
 * Description: Free a file structure; drop the global open file count, and
 *              drop the credential reference, if the fileglob has one, and
 *              destroy the instance mutex before freeing
 *
 * Parameters:  fg                              Pointer to fileglob to be
 *                                              freed
 *
 * Returns:     void
 */
void
fg_free(struct fileglob *fg)
{
        lck_mtx_lock_spin(file_flist_lock);
        LIST_REMOVE(fg, f_list);
        nfiles--;
        lck_mtx_unlock(file_flist_lock);

        if (IS_VALID_CRED(fg->fg_cred)) {
                kauth_cred_unref(&fg->fg_cred);
        }
        lck_mtx_destroy(&fg->fg_lock, file_lck_grp);

#if CONFIG_MACF
        mac_file_label_destroy(fg);
#endif
        FREE_ZONE(fg, sizeof *fg, M_FILEGLOB);
}


/*
 * fdexec
 *
 * Description: Perform close-on-exec processing for all files in a process
 *              that are either marked as close-on-exec, or which were in the
 *              process of being opened at the time of the execve
 *
 *              Also handles the case (via posix_spawn()) where -all-
 *              files except those marked with "inherit" as treated as
 *              close-on-exec.
 *
 * Parameters:  p                               Pointer to process calling
 *                                              execve
 *
 * Returns:     void
 *
 * Locks:       This function internally takes and drops proc_fdlock()
 *
 * Notes:       This function drops and retakes the kernel funnel; this is
 *              inherently unsafe, since another thread may have the
 *              proc_fdlock.
 *
 * XXX:         We should likely reverse the lock and funnel drop/acquire
 *              order to avoid the small race window; it's also possible that
 *              if the program doing the exec has an outstanding listen socket
 *              and a network connection is completed asynchronously that we
 *              will end up with a "ghost" socket reference in the new process.
 *
 *              This needs reworking to make it safe to remove the funnel from
 *              the execve and posix_spawn system calls.
 */
void
fdexec(proc_t p, short flags)
{
        struct filedesc *fdp = p->p_fd;
        int i;
        boolean_t cloexec_default = (flags & POSIX_SPAWN_CLOEXEC_DEFAULT) != 0;

        proc_fdlock(p);
        for (i = fdp->fd_lastfile; i >= 0; i--) {

                struct fileproc *fp = fdp->fd_ofiles[i];
                char *flagp = &fdp->fd_ofileflags[i];

                if (cloexec_default) {
                        /*
                         * Reverse the usual semantics of file descriptor
                         * inheritance - all of them should be closed
                         * except files marked explicitly as "inherit" and
                         * not marked close-on-exec.
                         */
                        if ((*flagp & (UF_EXCLOSE|UF_INHERIT)) != UF_INHERIT)
                                *flagp |= UF_EXCLOSE;
                        *flagp &= ~UF_INHERIT;
                }

                if (
                    ((*flagp & (UF_RESERVED|UF_EXCLOSE)) == UF_EXCLOSE)
#if CONFIG_MACF
                    || (fp && mac_file_check_inherit(proc_ucred(p), fp->f_fglob))
#endif
                ) {
                        if (i < fdp->fd_knlistsize)
                                knote_fdclose(p, i);
                        procfdtbl_clearfd(p, i);
                        if (i == fdp->fd_lastfile && i > 0)
                                fdp->fd_lastfile--;
                        if (i < fdp->fd_freefile)
                                fdp->fd_freefile = i;

                        /*
                         * Wait for any third party viewers (e.g., lsof)
                         * to release their references to this fileproc.
                         */
                        while (fp->f_iocount > 0) {
                                p->p_fpdrainwait = 1;
                                msleep(&p->p_fpdrainwait, &p->p_fdmlock, PRIBIO,
                                    "fpdrain", NULL);
                        }

                        closef_locked(fp, fp->f_fglob, p);

                        FREE_ZONE(fp, sizeof(*fp), M_FILEPROC);
                }
        }
        proc_fdunlock(p);
}


/*
 * fdcopy
 *
 * Description: Copy a filedesc structure.  This is normally used as part of
 *              forkproc() when forking a new process, to copy the per process
 *              open file table over to the new process.
 *
 * Parameters:  p                               Process whose open file table
 *                                              is to be copied (parent)
 *              uth_cdir                        Per thread current working
 *                                              cirectory, or NULL
 *
 * Returns:     NULL                            Copy failed
 *              !NULL                           Pointer to new struct filedesc
 *
 * Locks:       This function internally takes and drops proc_fdlock()
 *
 * Notes:       Files are copied directly, ignoring the new resource limits
 *              for the process that's being copied into.  Since the descriptor
 *              references are just additional references, this does not count
 *              against the number of open files on the system.
 *
 *              The struct filedesc includes the current working directory,
 *              and the current root directory, if the process is chroot'ed.
 *
 *              If the exec was called by a thread using a per thread current
 *              working directory, we inherit the working directory from the
 *              thread making the call, rather than from the process.
 *
 *              In the case of a failure to obtain a reference, for most cases,
 *              the file entry will be silently dropped.  There's an exception
 *              for the case of a chroot dir, since a failure to to obtain a
 *              reference there would constitute an "escape" from the chroot
 *              environment, which must not be allowed.  In that case, we will
 *              deny the execve() operation, rather than allowing the escape.
 */
struct filedesc *
fdcopy(proc_t p, vnode_t uth_cdir)
{
        struct filedesc *newfdp, *fdp = p->p_fd;
        int i;
        struct fileproc *ofp, *fp;
        vnode_t v_dir;

        MALLOC_ZONE(newfdp, struct filedesc *,
                        sizeof(*newfdp), M_FILEDESC, M_WAITOK);
        if (newfdp == NULL)
                return(NULL);

        proc_fdlock(p);

        /*
         * the FD_CHROOT flag will be inherited via this copy
         */
        (void) memcpy(newfdp, fdp, sizeof(*newfdp));

        /*
         * If we are running with per-thread current working directories,
         * inherit the new current working directory from the current thread
         * instead, before we take our references.
         */
        if (uth_cdir != NULLVP)
                newfdp->fd_cdir = uth_cdir;

        /*
         * For both fd_cdir and fd_rdir make sure we get
         * a valid reference... if we can't, than set
         * set the pointer(s) to NULL in the child... this
         * will keep us from using a non-referenced vp
         * and allows us to do the vnode_rele only on
         * a properly referenced vp
         */
        if ( (v_dir = newfdp->fd_cdir) ) {
                if (vnode_getwithref(v_dir) == 0) {
                        if ( (vnode_ref(v_dir)) )
                                newfdp->fd_cdir = NULL;
                        vnode_put(v_dir);
                } else
                        newfdp->fd_cdir = NULL;
        }
        if (newfdp->fd_cdir == NULL && fdp->fd_cdir) {
                /*
                 * we couldn't get a new reference on
                 * the current working directory being
                 * inherited... we might as well drop
                 * our reference from the parent also
                 * since the vnode has gone DEAD making
                 * it useless... by dropping it we'll
                 * be that much closer to recycling it
                 */
                vnode_rele(fdp->fd_cdir);
                fdp->fd_cdir = NULL;
        }

        if ( (v_dir = newfdp->fd_rdir) ) {
                if (vnode_getwithref(v_dir) == 0) {
                        if ( (vnode_ref(v_dir)) )
                                newfdp->fd_rdir = NULL;
                        vnode_put(v_dir);
                } else {
                        newfdp->fd_rdir = NULL;
                }
        }
        /* Coming from a chroot environment and unable to get a reference... */
        if (newfdp->fd_rdir == NULL && fdp->fd_rdir) {
                /*
                 * We couldn't get a new reference on
                 * the chroot directory being
                 * inherited... this is fatal, since
                 * otherwise it would constitute an
                 * escape from a chroot environment by
                 * the new process.
                 */
                if (newfdp->fd_cdir)
                        vnode_rele(newfdp->fd_cdir);
                FREE_ZONE(newfdp, sizeof *newfdp, M_FILEDESC);
                return(NULL);
        }
        newfdp->fd_refcnt = 1;

        /*
         * If the number of open files fits in the internal arrays
         * of the open file structure, use them, otherwise allocate
         * additional memory for the number of descriptors currently
         * in use.
         */
        if (newfdp->fd_lastfile < NDFILE)
                i = NDFILE;
        else {
                /*
                 * Compute the smallest multiple of NDEXTENT needed
                 * for the file descriptors currently in use,
                 * allowing the table to shrink.
                 */
                i = newfdp->fd_nfiles;
                while (i > 2 * NDEXTENT && i > newfdp->fd_lastfile * 2)
                        i /= 2;
        }
        proc_fdunlock(p);

        MALLOC_ZONE(newfdp->fd_ofiles, struct fileproc **,
                                i * OFILESIZE, M_OFILETABL, M_WAITOK);
        if (newfdp->fd_ofiles == NULL) {
                if (newfdp->fd_cdir)
                        vnode_rele(newfdp->fd_cdir);
                if (newfdp->fd_rdir)
                        vnode_rele(newfdp->fd_rdir);

                FREE_ZONE(newfdp, sizeof(*newfdp), M_FILEDESC);
                return(NULL);
        }
        (void) memset(newfdp->fd_ofiles, 0, i * OFILESIZE);
        proc_fdlock(p);

        newfdp->fd_ofileflags = (char *) &newfdp->fd_ofiles[i];
        newfdp->fd_nfiles = i;

        if (fdp->fd_nfiles > 0) {
                struct fileproc **fpp;
                char *flags;

                (void) memcpy(newfdp->fd_ofiles, fdp->fd_ofiles,
                                        (newfdp->fd_lastfile + 1) * sizeof(*fdp->fd_ofiles));
                (void) memcpy(newfdp->fd_ofileflags, fdp->fd_ofileflags,
                                        (newfdp->fd_lastfile + 1) * sizeof(*fdp->fd_ofileflags));

                /*
                 * kq descriptors cannot be copied.
                 */
                if (newfdp->fd_knlistsize != -1) {
                        fpp = &newfdp->fd_ofiles[newfdp->fd_lastfile];
                        for (i = newfdp->fd_lastfile; i >= 0; i--, fpp--) {
                                if (*fpp != NULL && (*fpp)->f_type == DTYPE_KQUEUE) {
                                        *fpp = NULL;
                                        newfdp->fd_ofileflags[i] = 0;
                                        if (i < newfdp->fd_freefile)
                                                newfdp->fd_freefile = i;
                                }
                                if (*fpp == NULL && i == newfdp->fd_lastfile && i > 0)
                                        newfdp->fd_lastfile--;
                        }
                        newfdp->fd_knlist = NULL;
                        newfdp->fd_knlistsize = -1;
                        newfdp->fd_knhash = NULL;
                        newfdp->fd_knhashmask = 0;
                }
                fpp = newfdp->fd_ofiles;
                flags = newfdp->fd_ofileflags;

                for (i = newfdp->fd_lastfile + 1; --i >= 0; fpp++, flags++)
                        if ((ofp = *fpp) != NULL && !(*flags & UF_RESERVED)) {
                                MALLOC_ZONE(fp, struct fileproc *, sizeof(struct fileproc), M_FILEPROC, M_WAITOK);
                                if (fp == NULL) {
                                        /*
                                         * XXX no room to copy, unable to
                                         * XXX safely unwind state at present
                                         */
                                        *fpp = NULL;
                                } else {
                                        bzero(fp, sizeof(struct fileproc));
                                        fp->f_flags = ofp->f_flags;
                                        //fp->f_iocount = ofp->f_iocount;
                                        fp->f_iocount = 0;
                                        fp->f_fglob = ofp->f_fglob;
                                        (void)fg_ref(fp);
                                        *fpp = fp;
                                }
                        } else {
                                if (i < newfdp->fd_freefile)
                                        newfdp->fd_freefile = i;
                                *fpp = NULL;
                                *flags = 0;
                        }
        }

        proc_fdunlock(p);
        return (newfdp);
}


/*
 * fdfree
 *
 * Description: Release a filedesc (per process open file table) structure;
 *              this is done on process exit(), or from forkproc_free() if
 *              the fork fails for some reason subsequent to a successful
 *              call to fdcopy()
 *
 * Parameters:  p                               Pointer to process going away
 *
 * Returns:     void
 *
 * Locks:       This function internally takes and drops proc_fdlock()
 */
void
fdfree(proc_t p)
{
        struct filedesc *fdp;
        struct fileproc *fp;
        int i;

        proc_fdlock(p);

        /* Certain daemons might not have file descriptors */
        fdp = p->p_fd;

        if ((fdp == NULL) || (--fdp->fd_refcnt > 0)) {
                proc_fdunlock(p);
                return;
        }
        if (fdp->fd_refcnt == 0xffff)
                panic("fdfree: bad fd_refcnt");

        /* Last reference: the structure can't change out from under us */

        if (fdp->fd_nfiles > 0 && fdp->fd_ofiles) {
                for (i = fdp->fd_lastfile; i >= 0; i--) {
                        if ((fp = fdp->fd_ofiles[i]) != NULL) {
                          
                          if (fdp->fd_ofileflags[i] & UF_RESERVED)
                                panic("fdfree: found fp with UF_RESERVED");

                                /* closef drops the iocount ... */
                                if ((fp->f_flags & FP_INCHRREAD) != 0) 
                                        fp->f_iocount++;
                                procfdtbl_reservefd(p, i);

                                if (i < fdp->fd_knlistsize)
                                        knote_fdclose(p, i);
                                if (fp->f_flags & FP_WAITEVENT) 
                                        (void)waitevent_close(p, fp);
                                (void) closef_locked(fp, fp->f_fglob, p);
                                FREE_ZONE(fp, sizeof(*fp), M_FILEPROC);
                        }
                }
                FREE_ZONE(fdp->fd_ofiles, fdp->fd_nfiles * OFILESIZE, M_OFILETABL);
                fdp->fd_ofiles = NULL;
                fdp->fd_nfiles = 0;
        }        

        proc_fdunlock(p);
        
        if (fdp->fd_cdir)
                vnode_rele(fdp->fd_cdir);
        if (fdp->fd_rdir)
                vnode_rele(fdp->fd_rdir);

        proc_fdlock_spin(p);
        p->p_fd = NULL;
        proc_fdunlock(p);

        if (fdp->fd_knlist)
                FREE(fdp->fd_knlist, M_KQUEUE);
        if (fdp->fd_knhash)
                FREE(fdp->fd_knhash, M_KQUEUE);

        FREE_ZONE(fdp, sizeof(*fdp), M_FILEDESC);
}


/*
 * closef_finish
 *
 * Description: Called on last open instance for a fileglob for a file being
 *              closed.
 *
 * Parameters:  fp                      Pointer to fileproc for fd
 *              fg                      Pointer to fileglob for fd
 *              p                       Pointer to proc structure
 *
 * Returns:     0                       Success
 *      <fo_close>:???                  Anything returnable by a per-fileops
 *                                      close function
 *
 * Note:        fp can only be non-NULL if p is also non-NULL.  If p is NULL,
 *              then fg must eith be locked (FHASLOCK) or must not have a
 *              type of DTYPE_VNODE.
 *
 *              On return, the fg is freed.
 *
 *              This function may block draining output to a character
 *              device on last close of that device.
 */
static int
closef_finish(struct fileproc *fp, struct fileglob *fg, proc_t p, vfs_context_t ctx)
{
        int error;


        /* fg_ops completed initialization? */
        if (fg->fg_ops)
                error = fo_close(fg, ctx);
        else
                error = 0;

        /* if fp is non-NULL, drain it out */
        if (((fp != (struct fileproc *)0) && ((fp->f_flags & FP_INCHRREAD) != 0))) {
                proc_fdlock_spin(p);
                if ( ((fp->f_flags & FP_INCHRREAD) != 0) ) {
                        fileproc_drain(p, fp);
                }
                proc_fdunlock(p);
        }
        fg_free(fg);

        return (error);
}

/*
 * closef_locked
 *
 * Description: Internal form of closef; called with proc_fdlock held
 *
 * Parameters:  fp                      Pointer to fileproc for fd
 *              fg                      Pointer to fileglob for fd
 *              p                       Pointer to proc structure
 *
 * Returns:     0                       Success
 *      closef_finish:???               Anything returnable by a per-fileops
 *                                      close function
 *
 * Note:        Decrements reference count on file structure; if this was the
 *              last reference, then closef_finish() is called
 *
 *              p and fp are allowed to  be NULL when closing a file that was
 *              being passed in a message (but only if we are called when this
 *              is NOT the last reference).
 */
int
closef_locked(struct fileproc *fp, struct fileglob *fg, proc_t p)
{
        struct vnode *vp;
        struct flock lf;
        struct vfs_context context;
        int error;

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

        /* Set up context with cred stashed in fg */
        if (p == current_proc())
                context.vc_thread = current_thread();
        else
                context.vc_thread = NULL;
        context.vc_ucred = fg->fg_cred;

        /*
         * POSIX record locking dictates that any close releases ALL
         * locks owned by this process.  This is handled by setting
         * a flag in the unlock to free ONLY locks obeying POSIX
         * semantics, and not to free BSD-style file locks.
         * If the descriptor was in a message, POSIX-style locks
         * aren't passed with the descriptor.
         */
        if (p && (p->p_ladvflag & P_LADVLOCK) && fg->fg_type == DTYPE_VNODE) {
                proc_fdunlock(p);

                lf.l_whence = SEEK_SET;
                lf.l_start = 0;
                lf.l_len = 0;
                lf.l_type = F_UNLCK;
                vp = (struct vnode *)fg->fg_data;

                if ( (error = vnode_getwithref(vp)) == 0 ) {
                        (void) VNOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_POSIX, &context);
                        (void)vnode_put(vp);
                }
                proc_fdlock(p);
        }
        lck_mtx_lock_spin(&fg->fg_lock);
        fg->fg_count--;

        if (fg->fg_count > 0) {
                lck_mtx_unlock(&fg->fg_lock);
                return (0);
        }
#if DIAGNOSTIC
        if (fg->fg_count != 0)
                panic("fg %p: being freed with bad fg_count (%d)", fg, fg->fg_count);
#endif

        if (fp && (fp->f_flags & FP_WRITTEN))
                fg->fg_flag |= FWASWRITTEN;

        fg->fg_lflags |= FG_TERM;
        lck_mtx_unlock(&fg->fg_lock);

        if (p)
                proc_fdunlock(p);
        error = closef_finish(fp, fg, p, &context);
        if (p)
                proc_fdlock(p);

        return(error);
}


/*
 * fileproc_drain
 *
 * Description: Drain out pending I/O operations
 *
 * Parameters:  p                               Process closing this file
 *              fp                              fileproc struct for the open
 *                                              instance on the file
 *
 * Returns:     void
 *
 * Locks:       Assumes the caller holds the proc_fdlock
 *
 * Notes:       For character devices, this occurs on the last close of the
 *              device; for all other file descriptors, this occurs on each
 *              close to prevent fd's from being closed out from under
 *              operations currently in progress and blocked
 *
 * See Also:    file_vnode(), file_socket(), file_drop(), and the cautions
 *              regarding their use and interaction with this function.
 */
void
fileproc_drain(proc_t p, struct fileproc * fp)
{
        struct vfs_context context;

        context.vc_thread = proc_thread(p);     /* XXX */
        context.vc_ucred = fp->f_fglob->fg_cred;

        fp->f_iocount-- ; /* (the one the close holds) */

        while (fp->f_iocount) {

                lck_mtx_convert_spin(&p->p_fdmlock);

                if (fp->f_fglob->fg_ops->fo_drain) {
                        (*fp->f_fglob->fg_ops->fo_drain)(fp, &context);
                }
                if ((fp->f_flags & FP_INSELECT) == FP_INSELECT) {
                        if (wait_queue_wakeup_all((wait_queue_t)fp->f_waddr, NULL, THREAD_INTERRUPTED) == KERN_INVALID_ARGUMENT)
                                panic("bad wait queue for wait_queue_wakeup_all %p", fp->f_waddr);
                } 
                if ((fp->f_flags & FP_SELCONFLICT) == FP_SELCONFLICT) {
                        if (wait_queue_wakeup_all(&select_conflict_queue, NULL, THREAD_INTERRUPTED) == KERN_INVALID_ARGUMENT)
                                panic("bad select_conflict_queue");
                }
                p->p_fpdrainwait = 1;

                msleep(&p->p_fpdrainwait, &p->p_fdmlock, PRIBIO, "fpdrain", NULL);

        }
#if DIAGNOSTIC
        if ((fp->f_flags & FP_INSELECT) != 0)
                panic("FP_INSELECT set on drained fp");
#endif
        if ((fp->f_flags & FP_SELCONFLICT) == FP_SELCONFLICT)
                fp->f_flags &= ~FP_SELCONFLICT;
}


/*
 * fp_free
 *
 * Description: Release the fd and free the fileproc associated with the fd
 *              in the per process open file table of the specified process;
 *              these values must correspond.
 *
 * Parameters:  p                               Process containing fd
 *              fd                              fd to be released
 *              fp                              fileproc to be freed
 *
 * Returns:     0                               Success
 *
 * Notes:       XXX function should be void - no one interprets the returns
 *              XXX code
 */
int
fp_free(proc_t p, int fd, struct fileproc * fp)
{
        proc_fdlock_spin(p);
        fdrelse(p, fd);
        proc_fdunlock(p);

        fg_free(fp->f_fglob);
        FREE_ZONE(fp, sizeof(*fp), M_FILEPROC);
        return(0);
}


/*
 * flock
 *
 * Description: Apply an advisory lock on a file descriptor.
 *
 * Parameters:  p                               Process making request
 *              uap->fd                         fd on which the lock is to be
 *                                              attempted
 *              uap->how                        (Un)Lock bits, including type
 *              retval                          Pointer to the call return area
 *              
 * Returns:     0                               Success
 *      fp_getfvp:EBADF                         Bad file descriptor
 *      fp_getfvp:ENOTSUP                       fd does not refer to a vnode
 *      vnode_getwithref:???
 *      VNOP_ADVLOCK:???
 *
 * Implicit returns:
 *              *retval (modified)              Size of dtable
 *
 * Notes:       Just attempt to get a record lock of the requested type on
 *              the entire file (l_whence = SEEK_SET, l_start = 0, l_len = 0).
 */
int
flock(proc_t p, struct flock_args *uap, __unused int32_t *retval)
{
        int fd = uap->fd;
        int how = uap->how;
        struct fileproc *fp;
        struct vnode *vp;
        struct flock lf;
        vfs_context_t ctx = vfs_context_current();
        int error=0;

        AUDIT_ARG(fd, uap->fd);
        if ( (error = fp_getfvp(p, fd, &fp, &vp)) ) {
                return(error);
        }
        if ( (error = vnode_getwithref(vp)) ) {
                goto out1;
        }
        AUDIT_ARG(vnpath, vp, ARG_VNODE1);

        lf.l_whence = SEEK_SET;
        lf.l_start = 0;
        lf.l_len = 0;
        if (how & LOCK_UN) {
                lf.l_type = F_UNLCK;
                fp->f_flag &= ~FHASLOCK;
                error = VNOP_ADVLOCK(vp, (caddr_t)fp->f_fglob, F_UNLCK, &lf, F_FLOCK, ctx);
                goto out;
        }
        if (how & LOCK_EX)
                lf.l_type = F_WRLCK;
        else if (how & LOCK_SH)
                lf.l_type = F_RDLCK;
        else {
                error = EBADF;
                goto out;
        }
#if CONFIG_MACF
        error = mac_file_check_lock(proc_ucred(p), fp->f_fglob, F_SETLK, &lf);
        if (error)
                goto out;
#endif
        fp->f_flag |= FHASLOCK;
        if (how & LOCK_NB) {
                error = VNOP_ADVLOCK(vp, (caddr_t)fp->f_fglob, F_SETLK, &lf, F_FLOCK, ctx);
                goto out;       
        }
        error = VNOP_ADVLOCK(vp, (caddr_t)fp->f_fglob, F_SETLK, &lf, F_FLOCK|F_WAIT, ctx);
out:
        (void)vnode_put(vp);
out1:
        fp_drop(p, fd, fp, 0);
        return(error);

}

/*
 * fileport_makeport
 *
 * Description: Obtain a Mach send right for a given file descriptor.
 *
 * Parameters:  p               Process calling fileport
 *              uap->fd         The fd to reference
 *              uap->portnamep  User address at which to place port name.
 *
 * Returns:     0               Success.
 *              EBADF           Bad file descriptor.
 *              EINVAL          File descriptor had type that cannot be sent, misc. other errors.
 *              EFAULT          Address at which to store port name is not valid.
 *              EAGAIN          Resource shortage.
 *
 * Implicit returns:
 *              On success, name of send right is stored at user-specified address.             
 */
int
fileport_makeport(proc_t p, struct fileport_makeport_args *uap,
    __unused int *retval)
{
        int err;
        int fd = uap->fd;
        user_addr_t user_portaddr = uap->portnamep;
        struct fileproc *fp = FILEPROC_NULL;
        struct fileglob *fg = NULL;
        ipc_port_t fileport;
        mach_port_name_t name = MACH_PORT_NULL;

        err = fp_lookup(p, fd, &fp, 0);
        if (err != 0) {
                goto out;
        }

        if (!filetype_issendable(fp->f_type)) {
                err = EINVAL;
                goto out;
        }

        /* Dropped when port is deallocated */
        fg = fp->f_fglob;
        fg_ref(fp);

        /* Allocate and initialize a port */
        fileport = fileport_alloc(fg);
        if (fileport == IPC_PORT_NULL) {
                err = EAGAIN;
                fg_drop(fp);
                goto out;
        }
        
        /* Add an entry.  Deallocates port on failure. */
        name = ipc_port_copyout_send(fileport, get_task_ipcspace(p->task));
        if (!MACH_PORT_VALID(name)) {
                err = EINVAL;
                goto out;
        } 
        
        err = copyout(&name, user_portaddr, sizeof(mach_port_name_t));
        if (err != 0) {
                goto out;
        }

        /* Tag the fileglob for debugging purposes */
        lck_mtx_lock_spin(&fg->fg_lock);
        fg->fg_lflags |= FG_PORTMADE;
        lck_mtx_unlock(&fg->fg_lock);

        fp_drop(p, fd, fp, 0);

        return 0;

out:
        if (MACH_PORT_VALID(name)) {
                /* Don't care if another thread races us to deallocate the entry */
                (void) mach_port_deallocate(get_task_ipcspace(p->task), name);
        }

        if (fp != FILEPROC_NULL) {
                fp_drop(p, fd, fp, 0);
        }

        return err;
}

void
fileport_releasefg(struct fileglob *fg)
{
        (void)closef_locked(NULL, fg, PROC_NULL);

        return;
}


/*
 * fileport_makefd
 *
 * Description: Obtain the file descriptor for a given Mach send right.
 *
 * Parameters:  p               Process calling fileport
 *              uap->port       Name of send right to file port.
 *
 * Returns:     0               Success
 *              EINVAL          Invalid Mach port name, or port is not for a file.
 *      fdalloc:EMFILE
 *      fdalloc:ENOMEM          Unable to allocate fileproc or extend file table.
 *
 * Implicit returns:
 *              *retval (modified)              The new descriptor
 */
int
fileport_makefd(proc_t p, struct fileport_makefd_args *uap, int32_t *retval)
{
        struct fileglob *fg;
        struct fileproc *fp = FILEPROC_NULL;
        ipc_port_t port = IPC_PORT_NULL;
        mach_port_name_t send = uap->port;
        kern_return_t res;
        int fd;
        int err;

        res = ipc_object_copyin(get_task_ipcspace(p->task),
                        send, MACH_MSG_TYPE_COPY_SEND, &port);

        if (res != KERN_SUCCESS) {
                err = EINVAL;
                goto out;
        }

        fg = fileport_port_to_fileglob(port);
        if (fg == NULL) {
                err = EINVAL;
                goto out;
        }

        MALLOC_ZONE(fp, struct fileproc *, sizeof(*fp), M_FILEPROC, M_WAITOK);
        if (fp == FILEPROC_NULL) {
                err = ENOMEM;
                goto out;
        }

        bzero(fp, sizeof(*fp));

        fp->f_fglob = fg;
        fg_ref(fp);

        proc_fdlock(p);
        err = fdalloc(p, 0, &fd);
        if (err != 0) {
                proc_fdunlock(p);
                goto out;
        }
        *fdflags(p, fd) |= UF_EXCLOSE;

        procfdtbl_releasefd(p, fd, fp);
        proc_fdunlock(p);

        *retval = fd;
        err = 0;
out:
        if ((fp != NULL) && (0 != err)) {
                FREE_ZONE(fp, sizeof(*fp), M_FILEPROC);
        } 

        if (IPC_PORT_NULL != port) {
                ipc_port_release_send(port);
        }

        return err;
}


/*
 * dupfdopen
 *
 * Description: Duplicate the specified descriptor to a free descriptor;
 *              this is the second half of fdopen(), above.
 *
 * Parameters:  fdp                             filedesc pointer to fill in
 *              indx                            fd to dup to
 *              dfd                             fd to dup from
 *              mode                            mode to set on new fd
 *              error                           command code
 *
 * Returns:     0                               Success
 *              EBADF                           Source fd is bad
 *              EACCES                          Requested mode not allowed
 *              !0                              'error', if not ENODEV or
 *                                              ENXIO
 *
 * Notes:       XXX This is not thread safe; see fdopen() above
 */
int
dupfdopen(struct filedesc *fdp, int indx, int dfd, int flags, int error)
{
        struct fileproc *wfp;
        struct fileproc *fp;
#if CONFIG_MACF
        int myerror;
#endif
        proc_t p = current_proc();

        /*
         * If the to-be-dup'd fd number is greater than the allowed number
         * of file descriptors, or the fd to be dup'd has already been
         * closed, reject.  Note, check for new == old is necessary as
         * falloc could allocate an already closed to-be-dup'd descriptor
         * as the new descriptor.
         */
        proc_fdlock(p);

        fp = fdp->fd_ofiles[indx];
        if (dfd < 0 || dfd >= fdp->fd_nfiles ||
                        (wfp = fdp->fd_ofiles[dfd]) == NULL || wfp == fp ||
                        (fdp->fd_ofileflags[dfd] & UF_RESERVED)) {

                proc_fdunlock(p);
                return (EBADF);
        }
#if CONFIG_MACF
        myerror = mac_file_check_dup(proc_ucred(p), wfp->f_fglob, dfd);
        if (myerror) {
                proc_fdunlock(p);
                return (myerror);
        }
#endif
        /*
         * There are two cases of interest here.
         *
         * For ENODEV simply dup (dfd) to file descriptor
         * (indx) and return.
         *
         * For ENXIO steal away the file structure from (dfd) and
         * store it in (indx).  (dfd) is effectively closed by
         * this operation.
         *
         * Any other error code is just returned.
         */
        switch (error) {
        case ENODEV:
                /*
                 * Check that the mode the file is being opened for is a
                 * subset of the mode of the existing descriptor.
                 */
                if (((flags & (FREAD|FWRITE)) | wfp->f_flag) != wfp->f_flag) {
                        proc_fdunlock(p);
                        return (EACCES);
                }
                if (indx > fdp->fd_lastfile)
                        fdp->fd_lastfile = indx;
                (void)fg_ref(wfp);

                if (fp->f_fglob)
                        fg_free(fp->f_fglob);
                fp->f_fglob = wfp->f_fglob;

                fdp->fd_ofileflags[indx] = fdp->fd_ofileflags[dfd] |
                        (flags & O_CLOEXEC) ? UF_EXCLOSE : 0;

                proc_fdunlock(p);
                return (0);

        default:
                proc_fdunlock(p);
                return (error);
        }
        /* NOTREACHED */
}


/*
 * fg_ref
 *
 * Description: Add a reference to a fileglob by fileproc
 *
 * Parameters:  fp                              fileproc containing fileglob
 *                                              pointer
 *
 * Returns:     void
 *
 * Notes:       XXX Should use OSAddAtomic?
 */
void
fg_ref(struct fileproc * fp)
{
        struct fileglob *fg;

        fg = fp->f_fglob;

        lck_mtx_lock_spin(&fg->fg_lock);

#if DIAGNOSTIC
        if ((fp->f_flags & ~((unsigned int)FP_VALID_FLAGS)) != 0)
                panic("fg_ref: invalid bits on fp %p", fp);

        if (fg->fg_count == 0)
                panic("fg_ref: adding fgcount to zeroed fg: fp %p fg %p",
                    fp, fg);
#endif
        fg->fg_count++;
        lck_mtx_unlock(&fg->fg_lock);
}


/*
 * fg_drop
 *
 * Description: Remove a reference to a fileglob by fileproc
 *
 * Parameters:  fp                              fileproc containing fileglob
 *                                              pointer
 *
 * Returns:     void
 *
 * Notes:       XXX Should use OSAddAtomic?
 */
void
fg_drop(struct fileproc * fp)
{
        struct fileglob *fg;

        fg = fp->f_fglob;
        lck_mtx_lock_spin(&fg->fg_lock);
        fg->fg_count--;
        lck_mtx_unlock(&fg->fg_lock);
}


/*
 * fg_insertuipc
 *
 * Description: Insert fileglob onto message queue
 *
 * Parameters:  fg                              Fileglob pointer to insert
 *
 * Returns:     void
 *
 * Locks:       Takes and drops fg_lock, potentially many times
 */
void
fg_insertuipc(struct fileglob * fg)
{
        int insertque = 0;

        lck_mtx_lock_spin(&fg->fg_lock);

        while (fg->fg_lflags & FG_RMMSGQ) {
                lck_mtx_convert_spin(&fg->fg_lock);

                fg->fg_lflags |= FG_WRMMSGQ;
                msleep(&fg->fg_lflags, &fg->fg_lock, 0, "fg_insertuipc", NULL);
        }

        fg->fg_count++;
        fg->fg_msgcount++;
        if (fg->fg_msgcount == 1) {
                fg->fg_lflags |= FG_INSMSGQ;
                insertque=1;
        }
        lck_mtx_unlock(&fg->fg_lock);

        if (insertque) {
                lck_mtx_lock_spin(uipc_lock);
                unp_gc_wait();
                LIST_INSERT_HEAD(&fmsghead, fg, f_msglist);
                lck_mtx_unlock(uipc_lock);
                lck_mtx_lock(&fg->fg_lock);
                fg->fg_lflags &= ~FG_INSMSGQ;
                if (fg->fg_lflags & FG_WINSMSGQ) {
                        fg->fg_lflags &= ~FG_WINSMSGQ;
                        wakeup(&fg->fg_lflags);
                }
                lck_mtx_unlock(&fg->fg_lock);
        }

}


/*
 * fg_removeuipc
 *
 * Description: Remove fileglob from message queue
 *
 * Parameters:  fg                              Fileglob pointer to remove
 *
 * Returns:     void
 *
 * Locks:       Takes and drops fg_lock, potentially many times
 */
void
fg_removeuipc(struct fileglob * fg)
{
        int removeque = 0;

        lck_mtx_lock_spin(&fg->fg_lock);
        while (fg->fg_lflags & FG_INSMSGQ) {
                lck_mtx_convert_spin(&fg->fg_lock);

                fg->fg_lflags |= FG_WINSMSGQ;
                msleep(&fg->fg_lflags, &fg->fg_lock, 0, "fg_removeuipc", NULL);
        }
        fg->fg_msgcount--;
        if (fg->fg_msgcount == 0) {
                fg->fg_lflags |= FG_RMMSGQ;
                removeque=1;
        }
        lck_mtx_unlock(&fg->fg_lock);

        if (removeque) {
                lck_mtx_lock_spin(uipc_lock);
                unp_gc_wait();
                LIST_REMOVE(fg, f_msglist);
                lck_mtx_unlock(uipc_lock);
                lck_mtx_lock(&fg->fg_lock);
                fg->fg_lflags &= ~FG_RMMSGQ;
                if (fg->fg_lflags & FG_WRMMSGQ) {
                        fg->fg_lflags &= ~FG_WRMMSGQ;
                        wakeup(&fg->fg_lflags);
                }
                lck_mtx_unlock(&fg->fg_lock);
        }
}


/*
 * fo_read
 *
 * Description: Generic fileops read indirected through the fileops pointer
 *              in the fileproc structure
 *
 * Parameters:  fp                              fileproc structure pointer
 *              uio                             user I/O structure pointer
 *              flags                           FOF_ flags
 *              ctx                             VFS context for operation
 *
 * Returns:     0                               Success
 *              !0                              Errno from read
 */
int
fo_read(struct fileproc *fp, struct uio *uio, int flags, vfs_context_t ctx)
{
        return ((*fp->f_ops->fo_read)(fp, uio, flags, ctx));
}


/*
 * fo_write
 *
 * Description: Generic fileops write indirected through the fileops pointer
 *              in the fileproc structure
 *
 * Parameters:  fp                              fileproc structure pointer
 *              uio                             user I/O structure pointer
 *              flags                           FOF_ flags
 *              ctx                             VFS context for operation
 *
 * Returns:     0                               Success
 *              !0                              Errno from write
 */
int
fo_write(struct fileproc *fp, struct uio *uio, int flags, vfs_context_t ctx)
{
        return((*fp->f_ops->fo_write)(fp, uio, flags, ctx));
}


/*
 * fo_ioctl
 *
 * Description: Generic fileops ioctl indirected through the fileops pointer
 *              in the fileproc structure
 *
 * Parameters:  fp                              fileproc structure pointer
 *              com                             ioctl command
 *              data                            pointer to internalized copy
 *                                              of user space ioctl command
 *                                              parameter data in kernel space
 *              ctx                             VFS context for operation
 *
 * Returns:     0                               Success
 *              !0                              Errno from ioctl
 *
 * Locks:       The caller is assumed to have held the proc_fdlock; this
 *              function releases and reacquires this lock.  If the caller
 *              accesses data protected by this lock prior to calling this
 *              function, it will need to revalidate/reacquire any cached
 *              protected data obtained prior to the call.
 */
int 
fo_ioctl(struct fileproc *fp, u_long com, caddr_t data, vfs_context_t ctx)
{
        int error;

        proc_fdunlock(vfs_context_proc(ctx));
        error = (*fp->f_ops->fo_ioctl)(fp, com, data, ctx);
        proc_fdlock(vfs_context_proc(ctx));
        return(error);
}       


/*
 * fo_select
 *
 * Description: Generic fileops select indirected through the fileops pointer
 *              in the fileproc structure
 *
 * Parameters:  fp                              fileproc structure pointer
 *              which                           select which
 *              wql                             pointer to wait queue list
 *              ctx                             VFS context for operation
 *
 * Returns:     0                               Success
 *              !0                              Errno from select
 */
int
fo_select(struct fileproc *fp, int which, void *wql, vfs_context_t ctx)
{       
        return((*fp->f_ops->fo_select)(fp, which, wql, ctx));
}


/*
 * fo_close
 *
 * Description: Generic fileops close indirected through the fileops pointer
 *              in the fileproc structure
 *
 * Parameters:  fp                              fileproc structure pointer for
 *                                              file to close
 *              ctx                             VFS context for operation
 *
 * Returns:     0                               Success
 *              !0                              Errno from close
 */
int
fo_close(struct fileglob *fg, vfs_context_t ctx)
{       
        return((*fg->fg_ops->fo_close)(fg, ctx));
}


/*
 * fo_kqfilter
 *
 * Description: Generic fileops kqueue filter indirected through the fileops
 *              pointer in the fileproc structure
 *
 * Parameters:  fp                              fileproc structure pointer
 *              kn                              pointer to knote to filter on
 *              ctx                             VFS context for operation
 *
 * Returns:     0                               Success
 *              !0                              Errno from kqueue filter
 */
int
fo_kqfilter(struct fileproc *fp, struct knote *kn, vfs_context_t ctx)
{
        return ((*fp->f_ops->fo_kqfilter)(fp, kn, ctx));
}

/*
 * The ability to send a file descriptor to another
 * process is opt-in by file type.
 */
boolean_t
filetype_issendable(file_type_t fdtype) 
{
        switch (fdtype) {
                case DTYPE_VNODE:
                case DTYPE_SOCKET:
                case DTYPE_PIPE:
                case DTYPE_PSXSHM:
                        return TRUE;
                default:
                        /* DTYPE_KQUEUE, DTYPE_FSEVENTS, DTYPE_PSXSEM */
                        return FALSE;
        }
}