include/sys/fs/namenode.h

   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 /*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
  22 /*        All Rights Reserved   */
  23
  24 /*
  25  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
  26  * Use is subject to license terms.
  27  */
  28
  29 #ifndef _SYS_FS_NAMENODE_H
  30 #define _SYS_FS_NAMENODE_H
  31
  32 #if defined(_KERNEL)
  33 #include <sys/vnode.h>
  34 #include <sys/vfs.h>
  35 #endif
  36
  37 #ifdef  __cplusplus
  38 extern "C" {
  39 #endif
  40
  41 /*
  42  * This structure is used to pass a file descriptor from user
  43  * level to the kernel. It is first used by fattach() and then
  44  * be NAMEFS.
  45  */
  46 struct namefd {
  47         int fd;
  48 };
  49
  50 #if defined(_KERNEL)
  51 /*
  52  * Each NAMEFS object is identified by a struct namenode/vnode pair.
  53  */
  54 struct namenode {
  55         struct vnode    *nm_vnode;      /* represents mounted file desc. */
  56         int             nm_flag;        /* flags defined below */
  57         struct vattr    nm_vattr;       /* attributes of mounted file desc. */
  58         struct vnode    *nm_filevp;     /* file desc. prior to mounting */
  59         struct file     *nm_filep;      /* file pointer of nm_filevp */
  60         struct vnode    *nm_mountpt;    /* mount point prior to mounting */
  61         struct namenode *nm_nextp;      /* next link in the linked list */
  62         kmutex_t        nm_lock;        /* protects nm_vattr */
  63 };
  64
  65 /*
  66  * Valid flags for namenodes.
  67  */
  68 #define NMNMNT          0x01    /* namenode not mounted */
  69
  70 /*
  71  * Macros to convert a vnode to a namenode, and vice versa.
  72  */
  73 #define VTONM(vp) ((struct namenode *)((vp)->v_data))
  74 #define NMTOV(nm) ((nm)->nm_vnode)
  75
  76 #define NM_FILEVP_HASH_SIZE     64
  77 #define NM_FILEVP_HASH_MASK     (NM_FILEVP_HASH_SIZE - 1)
  78 #define NM_FILEVP_HASH_SHIFT    7
  79 #define NM_FILEVP_HASH(vp)      (&nm_filevp_hash[(((uintptr_t)vp) >> \
  80         NM_FILEVP_HASH_SHIFT) & NM_FILEVP_HASH_MASK])
  81
  82 extern struct namenode *nm_filevp_hash[NM_FILEVP_HASH_SIZE];
  83 extern struct vfs namevfs;
  84
  85 extern int nameinit(int, char *);
  86 extern int nm_unmountall(struct vnode *, struct cred *);
  87 extern void nameinsert(struct namenode *);
  88 extern void nameremove(struct namenode *);
  89 extern struct namenode *namefind(struct vnode *, struct vnode *);
  90 extern uint64_t namenodeno_alloc(void);
  91 extern void namenodeno_free(uint64_t);
  92 extern const struct vnodeops nm_vnodeops;
  93 extern kmutex_t ntable_lock;
  94
  95 #endif /* _KERNEL */
  96
  97 #ifdef  __cplusplus
  98 }
  99 #endif
 100
 101 #endif  /* _SYS_FS_NAMENODE_H */