sys/fs/unionfs/unionfs.h

   1 /*-
   2  * Copyright (c) 1994 The Regents of the University of California.
   3  * Copyright (c) 1994 Jan-Simon Pendry.
   4  * Copyright (c) 2005, 2006 Masanori Ozawa <ozawa@ongs.co.jp>, ONGS Inc.
   5  * Copyright (c) 2006 Daichi Goto <daichi@freebsd.org>
   6  * All rights reserved.
   7  *
   8  * This code is derived from software donated to Berkeley by
   9  * Jan-Simon Pendry.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions and the following disclaimer.
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in the
  18  *    documentation and/or other materials provided with the distribution.
  19  * 4. Neither the name of the University nor the names of its contributors
  20  *    may be used to endorse or promote products derived from this software
  21  *    without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  *
  35  *      @(#)union.h     8.9 (Berkeley) 12/10/94
  36  * $FreeBSD: src/sys/fs/unionfs/union.h,v 1.36 2007/10/14 13:55:38 daichi Exp $
  37  */
  38
  39 #ifndef _MISCFS_UNION_H_
  40 #define _MISCFS_UNION_H_
  41
  42 #define UNIONFS_DEBUG
  43
  44 struct union_args {
  45         char            *target;        /* Target of loopback  */
  46         int             mntflags;       /* Options on the mount */
  47 };
  48 #define unionfs_args    union_args
  49
  50 #define UNMNT_ABOVE     0x0001          /* Target appears below mount point */
  51 #define UNMNT_BELOW     0x0002          /* Target appears below mount point */
  52 #define UNMNT_REPLACE   0x0003          /* Target replaces mount point */
  53 #define UNMNT_OPMASK    0x0003
  54
  55 #define UNMNT_BITS "\177\20" \
  56     "b\00above\0b\01below\0b\02replace\0"
  57
  58 #ifdef _KERNEL
  59
  60 /* copy method of attr from lower to upper */
  61 typedef enum _unionfs_copymode {
  62         UNIONFS_TRADITIONAL = 0,
  63         UNIONFS_TRANSPARENT,
  64         UNIONFS_MASQUERADE
  65 } unionfs_copymode;
  66
  67 /* whiteout policy of upper layer */
  68 typedef enum _unionfs_whitemode {
  69        UNIONFS_WHITE_ALWAYS = 0,
  70        UNIONFS_WHITE_WHENNEEDED
  71 } unionfs_whitemode;
  72
  73 struct unionfs_mount {
  74         struct vnode   *um_lowervp;     /* VREFed once */
  75         struct vnode   *um_uppervp;     /* VREFed once */
  76         struct vnode   *um_rootvp;      /* ROOT vnode */
  77         kmutex_t        um_lock;
  78         unionfs_copymode um_copymode;
  79         unionfs_whitemode um_whitemode;
  80         uid_t           um_uid;
  81         gid_t           um_gid;
  82         int             um_op;          /* Operation mode */
  83         u_short         um_udir;
  84         u_short         um_ufile;
  85 };
  86
  87 /* unionfs status list */
  88 struct unionfs_node_status {
  89         LIST_ENTRY(unionfs_node_status) uns_list;       /* Status list */
  90         pid_t           uns_pid;                /* current process id */
  91         lwpid_t         uns_lid;                /* current thread id */
  92         int             uns_node_flag;          /* uns flag */
  93         int             uns_lower_opencnt;      /* open count of lower */
  94         int             uns_upper_opencnt;      /* open count of upper */
  95         int             uns_lower_openmode;     /* open mode of lower */
  96         int             uns_readdir_status;     /* read status of readdir */
  97 };
  98
  99 /* union node status flags */
 100 #define UNS_OPENL_4_READDIR     0x01    /* open lower layer for readdir */
 101
 102 /* A cache of vnode references */
 103 struct unionfs_node {
 104         struct vnode   *un_lowervp;             /* lower side vnode */
 105         struct vnode   *un_uppervp;             /* upper side vnode */
 106         struct vnode   *un_dvp;                 /* parent unionfs vnode */
 107         struct vnode   *un_vnode;               /* Back pointer */
 108         LIST_HEAD(, unionfs_node_status) un_unshead;  /* unionfs status head */
 109         char           *un_path;                /* path */
 110         int             un_flag;                /* unionfs node flag */
 111 };
 112
 113 /*
 114  * unionfs node flags
 115  * It needs the vnode with exclusive lock, when changing the un_flag variable.
 116  */
 117 #define UNIONFS_OPENEXTL        0x01    /* openextattr (lower) */
 118 #define UNIONFS_OPENEXTU        0x02    /* openextattr (upper) */
 119
 120 #define MOUNTTOUNIONFSMOUNT(mp) ((struct unionfs_mount *)((mp)->mnt_data))
 121 #define VTOUNIONFS(vp) ((struct unionfs_node *)(vp)->v_data)
 122 #define UNIONFSTOV(xp) ((xp)->un_vnode)
 123
 124 int unionfs_nodeget(struct mount *mp, struct vnode *uppervp, struct vnode *lowervp, struct vnode *dvp, struct vnode **vpp, struct componentname *cnp);
 125 void unionfs_noderem(struct vnode *vp);
 126 void unionfs_get_node_status(struct unionfs_node *unp, struct unionfs_node_status **unspp);
 127 void unionfs_tryrem_node_status(struct unionfs_node *unp, struct unionfs_node_status *unsp);
 128
 129 int unionfs_check_rmdir(struct vnode *vp, kauth_cred_t cred);
 130 int unionfs_copyfile(struct unionfs_node *unp, int docopy, kauth_cred_t cred);
 131 void unionfs_create_uppervattr_core(struct unionfs_mount *ump, struct vattr *lva, struct vattr *uva);
 132 int unionfs_create_uppervattr(struct unionfs_mount *ump, struct vnode *lvp, struct vattr *uva, kauth_cred_t cred);
 133 int unionfs_mkshadowdir(struct unionfs_mount *ump, struct vnode *duvp, struct unionfs_node *unp, struct componentname *cnp);
 134 int unionfs_mkwhiteout(struct vnode *dvp, struct componentname *cnp, const char *path);
 135 int unionfs_relookup_for_create(struct vnode *dvp, struct componentname *cnp);
 136 int unionfs_relookup_for_delete(struct vnode *dvp, struct componentname *cnp);
 137 int unionfs_relookup_for_rename(struct vnode *dvp, struct componentname *cnp);
 138
 139 #ifdef DIAGNOSTIC
 140 struct vnode   *unionfs_checklowervp(struct vnode *vp, const char *fil, int lno);
 141 struct vnode   *unionfs_checkuppervp(struct vnode *vp, const char *fil, int lno);
 142 #define UNIONFSVPTOLOWERVP(vp) unionfs_checklowervp((vp), __FILE__, __LINE__)
 143 #define UNIONFSVPTOUPPERVP(vp) unionfs_checkuppervp((vp), __FILE__, __LINE__)
 144 #else
 145 #define UNIONFSVPTOLOWERVP(vp) (VTOUNIONFS(vp)->un_lowervp)
 146 #define UNIONFSVPTOUPPERVP(vp) (VTOUNIONFS(vp)->un_uppervp)
 147 #endif
 148
 149 extern int (**unionfs_vnodeop_p)(void *);
 150
 151 #ifdef MALLOC_DECLARE
 152 MALLOC_DECLARE(M_UNIONFSPATH);
 153 #endif
 154
 155 #ifdef UNIONFS_DEBUG
 156 #define UNIONFSDEBUG(format, args...) printf(format ,## args)
 157 #else
 158 #define UNIONFSDEBUG(format, args...)
 159 #endif                          /* UNIONFS_DEBUG */
 160
 161 #endif /* _KERNEL */
 162 #endif /* _MISCFS_UNION_H_ */