bsd/miscfs/devfs/devfsdefs.h

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /*
  23  * Copyright 1997,1998 Julian Elischer.  All rights reserved.
  24  * julian@freebsd.org
  25  *
  26  * Redistribution and use in source and binary forms, with or without
  27  * modification, are permitted provided that the following conditions are
  28  * met:
  29  *  1. Redistributions of source code must retain the above copyright
  30  *     notice, this list of conditions and the following disclaimer.
  31  *  2. Redistributions in binary form must reproduce the above copyright notice,
  32  *     this list of conditions and the following disclaimer in the documentation
  33  *     and/or other materials provided with the distribution.
  34  *
  35  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER ``AS IS'' AND ANY EXPRESS
  36  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  37  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  38  * DISCLAIMED.  IN NO EVENT SHALL THE HOLDER OR CONTRIBUTORS BE LIABLE FOR
  39  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  40  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  41  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  42  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  43  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  44  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  45  * SUCH DAMAGE.
  46  *
  47  * devfsdefs.h
  48  */
  49
  50 /*
  51  * HISTORY
  52  *  8-April-1999 Dieter Siegmund (dieter@apple.com)
  53  *      Ported to from FreeBSD 3.1
  54  *      Removed unnecessary/unused defines
  55  *      Renamed structures/elements to clarify usage in code.
  56  */
  57
  58
  59 #define DEVMAXNAMESIZE  32              /* XXX */
  60 #define DEVMAXPATHSIZE  128             /* XXX */
  61
  62 typedef enum {
  63     DEV_DIR,
  64     DEV_BDEV,
  65     DEV_CDEV,
  66     DEV_SLNK,
  67 } devfstype_t;
  68
  69 extern int (**devfs_vnodeop_p)(void *); /* our own vector array for dirs */
  70 extern int (**devfs_spec_vnodeop_p)(void *); /* our own vector array for devs */
  71 extern struct vfsops devfs_vfsops;
  72
  73 typedef struct devnode          devnode_t;
  74 typedef struct devdirent        devdirent_t;
  75 typedef union devnode_type      devnode_type_t;
  76
  77 struct devfs_stats {
  78     int                 nodes;
  79     int                 entries;
  80     int                 mounts;
  81     int                 stringspace;
  82 };
  83
  84 union devnode_type {
  85     dev_t               dev;
  86     struct {
  87         devdirent_t *   dirlist;
  88         devdirent_t * * dirlast;
  89         devnode_t *     parent;
  90         devdirent_t *   myname;         /* my entry in .. */
  91         int             entrycount;
  92     }Dir;
  93     struct {
  94         char *          name;   /* must be allocated separately */
  95         int             namelen;
  96     }Slnk;
  97 };
  98
  99 #define DN_ACCESS       0x0001          /* Access time update request. */
 100 #define DN_CHANGE       0x0002          /* Inode change time update request. */
 101 #define DN_UPDATE       0x0004          /* Modification time update request. */
 102 #define DN_MODIFIED     0x0008          /* Inode has been modified. */
 103 #define DN_RENAME       0x0010          /* Inode is being renamed. */
 104
 105 struct devnode
 106 {
 107     devfstype_t         dn_type;
 108     int                 dn_flags;
 109     u_short             dn_mode;
 110     uid_t               dn_uid;
 111     gid_t               dn_gid;
 112     struct timespec     dn_atime;/* time of last access */
 113     struct timespec     dn_mtime;/* time of last modification */
 114     struct timespec     dn_ctime;/* time file changed */
 115     int (***dn_ops)(void *);/* yuk... pointer to pointer(s) to funcs */
 116     int                 dn_links;/* how many file links does this node have? */
 117     struct devfsmount * dn_dvm; /* the mount structure for this 'plane' */
 118     struct vnode *      dn_vn;  /* address of last vnode that represented us */
 119     int                 dn_len;   /* of any associated info (e.g. dir data) */
 120     devdirent_t *       dn_linklist;/* circular list of hardlinks to this node */
 121     devdirent_t *       dn_last_lookup; /* name I was last looked up from */
 122     devnode_t *         dn_nextsibling; /* the list of equivalent nodes */
 123     devnode_t * *       dn_prevsiblingp;/* backpointer for the above */
 124     devnode_type_t      dn_typeinfo;
 125     int                 dn_delete;      /* mark for deletion */
 126 };
 127
 128 struct devdirent
 129 {
 130     /*-----------------------directory entry fields-------------*/
 131     char                de_name[DEVMAXNAMESIZE];
 132     devnode_t *         de_dnp;         /* the "inode" (devnode) pointer */
 133     devnode_t *         de_parent;      /* backpointer to the directory itself */
 134     devdirent_t *       de_next;        /* next object in this directory */
 135     devdirent_t *       *de_prevp;      /* previous pointer in directory linked list */
 136     devdirent_t *       de_nextlink;    /* next hardlink to this node */
 137     devdirent_t *       *de_prevlinkp;  /* previous hardlink pointer for this node */
 138 };
 139
 140 extern devdirent_t *            dev_root;
 141 extern struct lock__bsd__       devfs_lock;
 142 extern struct devfs_stats       devfs_stats;
 143
 144 /*
 145  * Rules for front nodes:
 146  * Dirs hava a strict 1:1 relationship with their OWN devnode
 147  * Symlinks similarly
 148  * Device Nodes ALWAYS point to the devnode that is linked
 149  * to the Backing node. (with a ref count)
 150  */
 151
 152 /*
 153  * DEVFS specific per/mount information, used to link a monted fs to a
 154  * particular 'plane' of front nodes.
 155  */
 156 struct devfsmount
 157 {
 158     struct mount *      mount;  /* vfs mount struct for this fs */
 159     devdirent_t *       plane_root;/* the root of this 'plane'  */
 160 };
 161
 162 /*
 163  * Prototypes for DEVFS virtual filesystem operations
 164  */
 165 #include <sys/lock.h>
 166 #include <miscfs/devfs/devfs_proto.h>
 167
 168 //#define HIDDEN_MOUNTPOINT     1
 169
 170 /* misc */
 171 #define M_DEVFSNAME     M_DEVFS
 172 #define M_DEVFSNODE     M_DEVFS
 173 #define M_DEVFSMNT      M_DEVFS
 174
 175 static __inline__ void
 176 getnanotime(struct timespec * t_p)
 177 {
 178     struct timeval tv;
 179
 180     microtime(&tv);
 181     t_p->tv_sec = tv.tv_sec;
 182     t_p->tv_nsec = tv.tv_usec * 1000;
 183     return;
 184 }
 185
 186 #define VTODN(vp)       ((devnode_t *)(vp)->v_data)
 187 extern void cache_purge(struct vnode *vp); /* vfs_cache.c */
 188
 189 static __inline__ int
 190 DEVFS_LOCK(struct proc * p)
 191 {
 192     return (lockmgr(&devfs_lock, LK_EXCLUSIVE, NULL, p));
 193 }
 194
 195 static __inline__ int
 196 DEVFS_UNLOCK(struct proc * p)
 197 {
 198     return (lockmgr(&devfs_lock, LK_RELEASE, NULL, p));
 199 }
 200
 201 static __inline__ void
 202 DEVFS_INCR_ENTRIES()
 203 {
 204     devfs_stats.entries++;
 205 }
 206
 207 static __inline__ void
 208 DEVFS_DECR_ENTRIES()
 209 {
 210     devfs_stats.entries--;
 211 }
 212
 213 static __inline__ void
 214 DEVFS_INCR_NODES()
 215 {
 216     devfs_stats.nodes++;
 217 }
 218
 219 static __inline__ void
 220 DEVFS_DECR_NODES()
 221 {
 222     devfs_stats.nodes--;
 223 }
 224
 225 static __inline__ void
 226 DEVFS_INCR_MOUNTS()
 227 {
 228     devfs_stats.mounts++;
 229 }
 230
 231 static __inline__ void
 232 DEVFS_DECR_MOUNTS()
 233 {
 234     devfs_stats.mounts--;
 235 }
 236
 237 static __inline__ void
 238 DEVFS_INCR_STRINGSPACE(int space)
 239 {
 240     devfs_stats.stringspace += space;
 241 }
 242
 243 static __inline__ void
 244 DEVFS_DECR_STRINGSPACE(int space)
 245 {
 246     devfs_stats.stringspace -= space;
 247     if (devfs_stats.stringspace < 0) {
 248         printf("DEVFS_DECR_STRINGSPACE: (%d - %d < 0)\n",
 249                devfs_stats.stringspace + space, space);
 250         devfs_stats.stringspace = 0;
 251     }
 252 }
 253
 254 static __inline__ void
 255 dn_times(devnode_t * dnp, struct timeval t1, struct timeval t2)
 256 {
 257     if (dnp->dn_flags & (DN_ACCESS | DN_CHANGE | DN_UPDATE)) {
 258         if (dnp->dn_flags & DN_ACCESS) {
 259             dnp->dn_atime.tv_sec = t1.tv_sec;
 260             dnp->dn_atime.tv_nsec = t1.tv_usec * 1000;
 261         }
 262         if (dnp->dn_flags & DN_UPDATE) {
 263             dnp->dn_mtime.tv_sec = t2.tv_sec;
 264             dnp->dn_mtime.tv_nsec = t2.tv_usec * 1000;
 265         }
 266         if (dnp->dn_flags & DN_CHANGE) {
 267             dnp->dn_ctime.tv_sec = time.tv_sec;
 268             dnp->dn_ctime.tv_nsec = time.tv_usec * 1000;
 269         }
 270         dnp->dn_flags &= ~(DN_ACCESS | DN_CHANGE | DN_UPDATE);
 271     }
 272     return;
 273 }
 274
 275 static __inline__ void
 276 dn_copy_times(devnode_t * target, devnode_t * source)
 277 {
 278     target->dn_atime = source->dn_atime;
 279     target->dn_mtime = source->dn_mtime;
 280     target->dn_ctime = source->dn_ctime;
 281     return;
 282 }