bsd/sys/vnode_internal.h

   1 /*
   2  * Copyright (c) 2000-2005 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 /* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
  23 /*
  24  * Copyright (c) 1989, 1993
  25  *      The Regents of the University of California.  All rights reserved.
  26  *
  27  * Redistribution and use in source and binary forms, with or without
  28  * modification, are permitted provided that the following conditions
  29  * are met:
  30  * 1. Redistributions of source code must retain the above copyright
  31  *    notice, this list of conditions and the following disclaimer.
  32  * 2. Redistributions in binary form must reproduce the above copyright
  33  *    notice, this list of conditions and the following disclaimer in the
  34  *    documentation and/or other materials provided with the distribution.
  35  * 3. All advertising materials mentioning features or use of this software
  36  *    must display the following acknowledgement:
  37  *      This product includes software developed by the University of
  38  *      California, Berkeley and its contributors.
  39  * 4. Neither the name of the University nor the names of its contributors
  40  *    may be used to endorse or promote products derived from this software
  41  *    without specific prior written permission.
  42  *
  43  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  44  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  45  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  46  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  47  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  48  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  49  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  50  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  51  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  52  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  53  * SUCH DAMAGE.
  54  *
  55  *      @(#)vnode.h     8.17 (Berkeley) 5/20/95
  56  */
  57
  58 #ifndef _SYS_VNODE_INTERNAL_H_
  59 #define _SYS_VNODE_INTERNAL_H_
  60
  61 #define INTERIM_FSNODE_LOCK     1
  62
  63 #include <sys/appleapiopts.h>
  64 #include <sys/cdefs.h>
  65 #include <sys/queue.h>
  66 #include <sys/lock.h>
  67
  68 #include <sys/time.h>
  69 #include <sys/uio.h>
  70
  71 #include <sys/vm.h>
  72 #include <sys/systm.h>
  73 #include <kern/locks.h>
  74 #include <vm/vm_kern.h>
  75 #include <sys/vnode.h>
  76 #include <sys/namei.h>
  77 #include <sys/vfs_context.h>
  78
  79
  80 struct lockf;
  81
  82 LIST_HEAD(buflists, buf);
  83
  84
  85 struct unsafe_fsnode {
  86         lck_mtx_t fsnodelock;
  87         int32_t   fsnode_count;
  88         void *    fsnodeowner;
  89 };
  90
  91 /*
  92  * Reading or writing any of these items requires holding the appropriate lock.
  93  * v_freelist is locked by the global vnode_list_lock
  94  * v_mntvnodes is locked by the mount_lock
  95  * v_nclinks and v_ncchildren are protected by the global name_cache_lock
  96  * v_cleanblkhd and v_dirtyblkhd and v_iterblkflags are locked via the global buf_mtxp
  97  * the rest of the structure is protected by the vnode_lock
  98  */
  99 struct vnode {
 100         lck_mtx_t v_lock;                       /* vnode mutex */
 101         TAILQ_ENTRY(vnode) v_freelist;          /* vnode freelist */
 102         TAILQ_ENTRY(vnode) v_mntvnodes;         /* vnodes for mount point */
 103         LIST_HEAD(, namecache) v_nclinks;       /* name cache entries that name this vnode */
 104         LIST_HEAD(, namecache) v_ncchildren;    /* name cache entries that regard us as there parent */
 105         vnode_t  v_defer_reclaimlist;           /* in case we have to defer the reclaim to avoid recursion */
 106         u_long   v_flag;                        /* vnode flags (see below) */
 107         u_short  v_lflag;                       /* vnode local and named ref flags */
 108         u_char   v_iterblkflags;                /* buf iterator flags */
 109         u_char   v_references;                  /* number of times io_count has been granted */
 110         int32_t  v_kusecount;                   /* count of in-kernel refs */
 111         int32_t  v_usecount;                    /* reference count of users */
 112         int32_t  v_iocount;                     /* iocounters */
 113         void *   v_owner;                       /* act that owns the vnode */
 114         enum vtype v_type;                      /* vnode type */
 115         u_long   v_id;                          /* identity of vnode contents */
 116         union {
 117                 struct mount    *vu_mountedhere;/* ptr to mounted vfs (VDIR) */
 118                 struct socket   *vu_socket;     /* unix ipc (VSOCK) */
 119                 struct specinfo *vu_specinfo;   /* device (VCHR, VBLK) */
 120                 struct fifoinfo *vu_fifoinfo;   /* fifo (VFIFO) */
 121                 struct ubc_info *vu_ubcinfo;    /* valid for (VREG) */
 122         } v_un;
 123         struct  buflists v_cleanblkhd;          /* clean blocklist head */
 124         struct  buflists v_dirtyblkhd;          /* dirty blocklist head */
 125         kauth_cred_t v_cred;
 126         int     v_cred_timestamp;
 127         long    v_numoutput;                    /* num of writes in progress */
 128         long    v_writecount;                   /* reference count of writers */
 129         char *  v_name;                         /* name component of the vnode */
 130         vnode_t v_parent;                       /* pointer to parent vnode */
 131 #ifdef INTERIM_FSNODE_LOCK
 132         struct lockf    *v_lockf;               /* advisory lock list head */
 133         struct unsafe_fsnode *v_unsafefs;       /* pointer to struct used to lock */
 134 #endif                                          /* vnodes on unsafe filesystems */
 135         int     (**v_op)(void *);               /* vnode operations vector */
 136         enum vtagtype v_tag;                    /* type of underlying data */
 137         mount_t v_mount;                        /* ptr to vfs we are in */
 138         void *  v_data;                         /* private data for fs */
 139 };
 140
 141 #define v_mountedhere   v_un.vu_mountedhere
 142 #define v_socket        v_un.vu_socket
 143 #define v_specinfo      v_un.vu_specinfo
 144 #define v_fifoinfo      v_un.vu_fifoinfo
 145 #define v_ubcinfo       v_un.vu_ubcinfo
 146
 147
 148 /*
 149  * v_iterblkflags
 150  */
 151 #define VBI_ITER                0x1
 152 #define VBI_ITERWANT            0x2
 153 #define VBI_CLEAN               0x4
 154 #define VBI_DIRTY               0x8
 155 #define VBI_NEWBUF              0x10
 156
 157
 158 /*
 159  * v_lflags
 160  */
 161 #define VL_SUSPENDED    0x0001          /* vnode is suspended */
 162 #define VL_DRAIN        0x0002          /* vnode is being drained */
 163 #define VL_TERMINATE    0x0004          /* vnode is marked for termination */
 164 #define VL_TERMWANT     0x0008          /* vnode is marked for termination */
 165 #define VL_DEAD         0x0010          /* vnode is dead and completed recycle */
 166 #define VL_MARKTERM     0x0020          /* vnode is dead and completed recycle */
 167 #define VL_MOUNTDEAD    0x0040          /* v_moutnedhere is dead   */
 168 #define VL_NEEDINACTIVE 0x0080          /* delay VNOP_INACTIVE until iocount goes to 0 */
 169
 170 #define VNAMED_UBC      0x2000          /* ubc named reference */
 171 #define VNAMED_MOUNT    0x4000          /* mount point named reference */
 172 #define VNAMED_FSHASH   0x8000          /* FS hash named reference */
 173
 174
 175 /*
 176  * v_flags
 177  */
 178 #define VROOT           0x000001        /* root of its file system */
 179 #define VTEXT           0x000002        /* vnode is a pure text prototype */
 180 #define VSYSTEM         0x000004        /* vnode being used by kernel */
 181 #define VISTTY          0x000008        /* vnode represents a tty */
 182 #define VWASMAPPED      0x000010        /* vnode was mapped before */
 183 #define VTERMINATE      0x000020        /* terminating memory object */
 184 #define VTERMWANT       0x000040        /* wating for memory object death */
 185 #define VMOUNT          0x000080        /* mount operation in progress */
 186 #define VBWAIT          0x000100        /* waiting for output to complete */
 187 #define VALIASED        0x000200        /* vnode has an alias */
 188 #define VNOCACHE_DATA   0x000400        /* don't keep data cached once it's been consumed */
 189 #define VSTANDARD       0x000800        /* vnode obtained from common pool */
 190 #define VAGE            0x001000        /* Insert vnode at head of free list */
 191 #define VRAOFF          0x002000        /* read ahead disabled */
 192 #define VNCACHEABLE     0x004000        /* vnode is allowed to be put back in name cache */
 193 #define VUINACTIVE      0x008000        /* UBC vnode is on inactive list */
 194 #define VSWAP           0x010000        /* vnode is being used as swapfile */
 195 #define VTHROTTLED      0x020000        /* writes or pageouts have been throttled */
 196                 /* wakeup tasks waiting when count falls below threshold */
 197 #define VNOFLUSH        0x040000        /* don't vflush() if SKIPSYSTEM */
 198 #define VLOCKLOCAL      0x080000        /* this vnode does adv locking in vfs */
 199 #define VISHARDLINK     0x100000        /* hard link needs special processing on lookup and in volfs */
 200
 201 #define VCRED_EXPIRED   2               /* number of seconds to keep cached credential valid */
 202
 203
 204 /*
 205  * Global vnode data.
 206  */
 207 extern  struct vnode *rootvnode;        /* root (i.e. "/") vnode */
 208
 209
 210 /*
 211  * Mods for exensibility.
 212  */
 213
 214 /*
 215  * Flags for vdesc_flags:
 216  */
 217 #define VDESC_MAX_VPS           16
 218 /* Low order 16 flag bits are reserved for willrele flags for vp arguments. */
 219 #define VDESC_VP0_WILLRELE      0x0001
 220 #define VDESC_VP1_WILLRELE      0x0002
 221 #define VDESC_VP2_WILLRELE      0x0004
 222 #define VDESC_VP3_WILLRELE      0x0008
 223 #define VDESC_NOMAP_VPP         0x0100
 224 #define VDESC_VPP_WILLRELE      0x0200
 225
 226 /*
 227  * VDESC_NO_OFFSET is used to identify the end of the offset list
 228  * and in places where no such field exists.
 229  */
 230 #define VDESC_NO_OFFSET -1
 231
 232 /*
 233  * This structure describes the vnode operation taking place.
 234  */
 235 struct vnodeop_desc {
 236         int     vdesc_offset;           /* offset in vector--first for speed */
 237         char    *vdesc_name;            /* a readable name for debugging */
 238         int     vdesc_flags;            /* VDESC_* flags */
 239
 240         /*
 241          * These ops are used by bypass routines to map and locate arguments.
 242          * Creds and procs are not needed in bypass routines, but sometimes
 243          * they are useful to (for example) transport layers.
 244          * Nameidata is useful because it has a cred in it.
 245          */
 246         int     *vdesc_vp_offsets;      /* list ended by VDESC_NO_OFFSET */
 247         int     vdesc_vpp_offset;       /* return vpp location */
 248         int     vdesc_cred_offset;      /* cred location, if any */
 249         int     vdesc_proc_offset;      /* proc location, if any */
 250         int     vdesc_componentname_offset; /* if any */
 251         int     vdesc_context_offset;   /* context location, if any */
 252         /*
 253          * Finally, we've got a list of private data (about each operation)
 254          * for each transport layer.  (Support to manage this list is not
 255          * yet part of BSD.)
 256          */
 257         caddr_t *vdesc_transports;
 258 };
 259
 260 /*
 261  * A list of all the operation descs.
 262  */
 263 extern struct vnodeop_desc *vnodeop_descs[];
 264
 265 /*
 266  * Interlock for scanning list of vnodes attached to a mountpoint
 267  */
 268 extern void * mntvnode_slock;
 269
 270 /*
 271  * This macro is very helpful in defining those offsets in the vdesc struct.
 272  *
 273  * This is stolen from X11R4.  I ingored all the fancy stuff for
 274  * Crays, so if you decide to port this to such a serious machine,
 275  * you might want to consult Intrisics.h's XtOffset{,Of,To}.
 276  */
 277 #define VOPARG_OFFSET(p_type,field) \
 278         ((int) (((char *) (&(((p_type)NULL)->field))) - ((char *) NULL)))
 279 #define VOPARG_OFFSETOF(s_type,field) \
 280         VOPARG_OFFSET(s_type*,field)
 281 #define VOPARG_OFFSETTO(S_TYPE,S_OFFSET,STRUCT_P) \
 282         ((S_TYPE)(((char*)(STRUCT_P))+(S_OFFSET)))
 283
 284
 285
 286 /*
 287  * VOCALL calls an op given an ops vector.  We break it out because BSD's
 288  * vclean changes the ops vector and then wants to call ops with the old
 289  * vector.
 290  */
 291 #define VOCALL(OPSV,OFF,AP) (( *((OPSV)[(OFF)])) (AP))
 292
 293 /*
 294  * This call works for vnodes in the kernel.
 295  */
 296 #define VCALL(VP,OFF,AP) VOCALL((VP)->v_op,(OFF),(AP))
 297 #define VDESC(OP) (& __CONCAT(OP,_desc))
 298 #define VOFFSET(OP) (VDESC(OP)->vdesc_offset)
 299
 300
 301
 302 int     build_path(vnode_t first_vp, char *buff, int buflen, int *outlen);
 303 int     bdevvp(dev_t dev, struct vnode **vpp);
 304 void    cvtstat(struct stat *st, struct ostat *ost);
 305 void    vprint(const char *label, struct vnode *vp);
 306
 307
 308 __private_extern__ int is_package_name(char *name, int len);
 309 __private_extern__ int set_package_extensions_table(void *data, int nentries, int maxwidth);
 310 int     vn_rdwr(enum uio_rw rw, struct vnode *vp, caddr_t base,
 311                         int len, off_t offset, enum uio_seg segflg, int ioflg,
 312                         struct ucred *cred, int *aresid, struct proc *p);
 313 int     vn_rdwr_64(enum uio_rw rw, struct vnode *vp, uint64_t base,
 314                         int64_t len, off_t offset, enum uio_seg segflg,
 315                         int ioflg, struct ucred *cred, int *aresid,
 316                         struct proc *p);
 317 void    fifo_printinfo(struct vnode *vp);
 318 int     vn_lock(struct vnode *vp, int flags, struct proc *p);
 319 int     vn_open(struct nameidata *ndp, int fmode, int cmode);
 320 int     vn_open_modflags(struct nameidata *ndp, int *fmode, int cmode);
 321 int     vn_open_auth(struct nameidata *ndp, int *fmode, struct vnode_attr *);
 322 int     vn_close(vnode_t, int flags, struct ucred *cred, struct proc *p);
 323
 324 #define VN_CREATE_NOAUTH                (1<<0)
 325 #define VN_CREATE_NOINHERIT             (1<<1)
 326 errno_t vn_create(vnode_t, vnode_t *, struct componentname *, struct vnode_attr *, int flags, vfs_context_t);
 327
 328
 329 int     vn_getxattr(vnode_t, const char *, uio_t, size_t *, int, vfs_context_t);
 330 int     vn_setxattr(vnode_t, const char *, uio_t, int, vfs_context_t);
 331 int     vn_removexattr(vnode_t, const char *, int, vfs_context_t);
 332 int     vn_listxattr(vnode_t, uio_t, size_t *, int, vfs_context_t);
 333
 334 void    name_cache_lock(void);
 335 void    name_cache_unlock(void);
 336
 337 char *  vnode_getname(vnode_t vp);
 338 void    vnode_putname(char *name);
 339
 340 vnode_t vnode_getparent(vnode_t vp);
 341
 342 int vn_pathconf(vnode_t, int, register_t *, vfs_context_t);
 343
 344 void    vnode_list_lock(void);
 345 void    vnode_list_unlock(void);
 346 int     vnode_ref_ext(vnode_t, int);
 347 void    vnode_rele_ext(vnode_t, int, int);
 348 void    vnode_rele_internal(vnode_t, int, int, int);
 349 int     vnode_getwithref(vnode_t);
 350 int     vnode_put_locked(vnode_t);
 351
 352 int     vnode_issock(vnode_t);
 353
 354 void    unlock_fsnode(vnode_t, int *);
 355 int     lock_fsnode(vnode_t, int *);
 356
 357 errno_t vnode_resume(vnode_t);
 358
 359 errno_t vnode_size(vnode_t, off_t *, vfs_context_t);
 360 errno_t vnode_setsize(vnode_t, off_t, int ioflag, vfs_context_t);
 361 int     vnode_setattr_fallback(vnode_t vp, struct vnode_attr *vap, vfs_context_t ctx);
 362
 363 void SPECHASH_LOCK(void);
 364 void SPECHASH_UNLOCK(void);
 365
 366 int check_cdevmounted(dev_t, enum vtype, int *);
 367
 368 void    vnode_authorize_init(void);
 369
 370 #endif /* !_SYS_VNODE_INTERNAL_H_ */