usr/src/uts/common/syscall/mount.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 /*      Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T     */
  28 /*        All Rights Reserved   */
  29
  30 /*
  31  * Portions of this source code were derived from Berkeley 4.3 BSD
  32  * under license from the Regents of the University of California.
  33  */
  34
  35 #pragma ident   "%Z%%M% %I%     %E% SMI"
  36
  37 #include <sys/types.h>
  38 #include <sys/t_lock.h>
  39 #include <sys/param.h>
  40 #include <sys/errno.h>
  41 #include <sys/user.h>
  42 #include <sys/fstyp.h>
  43 #include <sys/kmem.h>
  44 #include <sys/systm.h>
  45 #include <sys/mount.h>
  46 #include <sys/vfs.h>
  47 #include <sys/cred.h>
  48 #include <sys/vnode.h>
  49 #include <sys/dnlc.h>
  50 #include <sys/file.h>
  51 #include <sys/time.h>
  52 #include <sys/cmn_err.h>
  53 #include <sys/swap.h>
  54 #include <sys/debug.h>
  55 #include <sys/pathname.h>
  56 #include <sys/cladm.h>
  57
  58 /*
  59  * System calls.
  60  */
  61
  62 /*
  63  * "struct mounta" defined in sys/vfs.h.
  64  */
  65
  66 /* ARGSUSED */
  67 int
  68 mount(long *lp, rval_t *rp)
  69 {
  70         vnode_t *vp = NULL;
  71         struct vfs *vfsp;       /* dummy argument */
  72         int error;
  73         struct mounta *uap;
  74 #if defined(_LP64)
  75         struct mounta native;
  76
  77         /*
  78          * Make a struct mounta if we are DATAMODEL_LP64
  79          */
  80         uap = &native;
  81         uap->spec = (char *)*lp++;
  82         uap->dir = (char *)*lp++;
  83         uap->flags = (int)*lp++;
  84         uap->fstype = (char *)*lp++;
  85         uap->dataptr = (char *)*lp++;
  86         uap->datalen = (int)*lp++;
  87         uap->optptr = (char *)*lp++;
  88         uap->optlen = (int)*lp++;
  89 #else   /* !defined(_LP64) */
  90         /*
  91          * 32 bit kernels can take a shortcut and just cast
  92          * the args array to the structure.
  93          */
  94         uap = (struct mounta *)lp;
  95 #endif  /* _LP64 */
  96         /*
  97          * Resolve second path name (mount point).
  98          */
  99         if (error = lookupname(uap->dir, UIO_USERSPACE, FOLLOW, NULLVPP, &vp))
 100                 return (set_errno(error));
 101
 102         /*
 103          * Some mount flags are disallowed through the system call interface.
 104          */
 105         uap->flags &= MS_MASK;
 106
 107         if ((vp->v_flag & VPXFS) && ((uap->flags & MS_GLOBAL) != MS_GLOBAL)) {
 108                 /*
 109                  * Clustering: if we're doing a mount onto the global
 110                  * namespace, and the mount is not a global mount, return
 111                  * an error.
 112                  */
 113                 error = ENOTSUP;
 114         } else if (uap->flags & MS_GLOBAL) {
 115                 /*
 116                  * Clustering: global mount specified.
 117                  */
 118                 if ((cluster_bootflags & CLUSTER_BOOTED) == 0) {
 119                         /*
 120                          * If we're not booted as a cluster,
 121                          * global mounts are not allowed.
 122                          */
 123                         error = ENOTSUP;
 124                 } else {
 125                         error = domount("pxfs", uap, vp, CRED(), &vfsp);
 126                         if (!error)
 127                                 VFS_RELE(vfsp);
 128                 }
 129         } else {
 130                 error = domount(NULL, uap, vp, CRED(), &vfsp);
 131                 if (!error)
 132                         VFS_RELE(vfsp);
 133         }
 134         VN_RELE(vp);
 135         rp->r_val2 = error;
 136         return (error ? set_errno(error) : 0);
 137 }