kernel/fs/objfs/objfs_root.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 (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
  23  * Use is subject to license terms.
  24  */
  25
  26 #pragma ident   "%Z%%M% %I%     %E% SMI"
  27
  28
  29 #include <sys/fs_subr.h>
  30
  31 #include <sys/errno.h>
  32 #include <sys/kmem.h>
  33 #include <sys/modctl.h>
  34 #include <sys/objfs.h>
  35 #include <sys/objfs_impl.h>
  36 #include <sys/vfs.h>
  37 #include <sys/systm.h>
  38
  39 extern int last_module_id;
  40
  41 static const struct vnodeops objfs_ops_root;
  42
  43 static int objfs_root_do_lookup(vnode_t *, const char *, vnode_t **, ino64_t *,
  44     cred_t *, int, int *, pathname_t *);
  45 static int objfs_root_do_readdir(vnode_t *, void *, int *,
  46     offset_t *, offset_t *, void *, int);
  47
  48 vnode_t *
  49 objfs_create_root(vfs_t *vfsp)
  50 {
  51         vnode_t *vp = gfs_root_create(sizeof (objfs_rootnode_t), vfsp,
  52             &objfs_ops_root, OBJFS_INO_ROOT, NULL, NULL, OBJFS_NAME_MAX,
  53             objfs_root_do_readdir, objfs_root_do_lookup);
  54
  55         return (vp);
  56 }
  57
  58 /* ARGSUSED */
  59 static int
  60 objfs_root_getattr(vnode_t *vp, vattr_t *vap, int flags, cred_t *cr,
  61         caller_context_t *ct)
  62 {
  63         vap->va_type = VDIR;
  64         vap->va_mode = 0555;
  65         vap->va_nodeid = gfs_file_inode(vp);
  66         vap->va_nlink = objfs_nobjs() + 2;
  67         vap->va_size = vap->va_nlink;
  68         vap->va_atime.tv_sec = vp->v_vfsp->vfs_mtime;
  69         vap->va_atime.tv_nsec = 0;
  70         vap->va_mtime = vap->va_ctime = vap->va_atime;
  71         return (objfs_common_getattr(vp, vap));
  72 }
  73
  74 /* ARGSUSED */
  75 static int
  76 objfs_root_do_lookup(vnode_t *vp, const char *nm, vnode_t **vpp, ino64_t *inop,
  77     cred_t *cr, int flags, int *deflags, pathname_t *rpnp)
  78 {
  79         int result = ENOENT;
  80         struct modctl *mp;
  81
  82         /*
  83          * Run through all the loaded modules on the system looking for
  84          * a matching module name.
  85          */
  86         mutex_enter(&mod_lock);
  87         mp = &modules;
  88         do {
  89                 if (mp->mod_loaded &&
  90                     strcmp(nm, mp->mod_modname) == 0) {
  91                         /*
  92                          * We drop mod_lock in order to do allocations,
  93                          * as modctls are persistent.
  94                          */
  95                         mutex_exit(&mod_lock);
  96                         *vpp = objfs_create_odirnode(vp, mp);
  97                         *inop = OBJFS_INO_ODIR(mp->mod_id);
  98                         mutex_enter(&mod_lock);
  99                         result = 0;
 100                         break;
 101                 }
 102         } while ((mp = mp->mod_next) != &modules);
 103         mutex_exit(&mod_lock);
 104
 105         return (result);
 106 }
 107
 108 /* ARGSUSED */
 109 int
 110 objfs_root_do_readdir(vnode_t *vp, void *dp, int *eofp,
 111     offset_t *offp, offset_t *nextp, void *data, int flags)
 112 {
 113         struct modctl **mpp = data;
 114         struct modctl *mp = *mpp;
 115         struct dirent *odp = dp;
 116
 117         ASSERT(!(flags & V_RDDIR_ENTFLAGS));
 118
 119         mutex_enter(&mod_lock);
 120
 121         /* Check for EOF */
 122         if (*offp >= last_module_id) {
 123                 *eofp = 1;
 124                 mutex_exit(&mod_lock);
 125                 return (0);
 126         }
 127
 128         /*
 129          * Find the appropriate modctl
 130          */
 131         while (mp->mod_id < *offp) {
 132                 mp = mp->mod_next;
 133                 ASSERT(mp != &modules);
 134         }
 135
 136         while (!mp->mod_loaded && mp != &modules)
 137                 mp = mp->mod_next;
 138
 139         if (mp == &modules && *offp != 0) {
 140                 *eofp = 1;
 141                 mutex_exit(&mod_lock);
 142                 return (0);
 143         }
 144
 145         /*
 146          * The modctl will not change, as they are persistent.
 147          */
 148         mutex_exit(&mod_lock);
 149
 150         (void) strncpy(odp->d_name, mp->mod_modname, OBJFS_NAME_MAX);
 151         odp->d_ino = OBJFS_INO_ODIR(mp->mod_id);
 152         *offp = mp->mod_id;
 153         *nextp = mp->mod_id + 1;
 154
 155         return (0);
 156 }
 157
 158 /* ARGSUSED */
 159 static int
 160 objfs_root_readdir(vnode_t *vp, uio_t *uiop, cred_t *cr, int *eofp,
 161         caller_context_t *ct, int flags)
 162 {
 163         struct modctl *mp = &modules;
 164
 165         return (gfs_dir_readdir(vp, uiop, eofp, &mp, cr, ct, flags));
 166 }
 167
 168 static const struct vnodeops objfs_ops_root = {
 169         .vnop_name = "objfs root directory",
 170         .vop_open = objfs_dir_open,
 171         .vop_close = objfs_common_close,
 172         .vop_ioctl = fs_inval,
 173         .vop_getattr = objfs_root_getattr,
 174         .vop_access = objfs_dir_access,
 175         .vop_readdir = objfs_root_readdir,
 176         .vop_lookup = gfs_vop_lookup,
 177         .vop_seek = fs_seek,
 178         .vop_inactive = gfs_vop_inactive,
 179 };