FreeBSD/Linux Kernel Cross Reference
sys/fs/unionfs/union.h

     /*-
      * SPDX-License-Identifier: BSD-3-Clause
      *
      * Copyright (c) 1994 The Regents of the University of California.
      * Copyright (c) 1994 Jan-Simon Pendry.
      * Copyright (c) 2005, 2006 Masanori Ozawa <ozawa@ongs.co.jp>, ONGS Inc.
      * Copyright (c) 2006 Daichi Goto <daichi@freebsd.org>
      * All rights reserved.
      *
     * This code is derived from software donated to Berkeley by
     * Jan-Simon Pendry.
     *
     * Redistribution and use in source and binary forms, with or without
     * modification, are permitted provided that the following conditions
     * are met:
     * 1. Redistributions of source code must retain the above copyright
     *    notice, this list of conditions and the following disclaimer.
     * 2. Redistributions in binary form must reproduce the above copyright
     *    notice, this list of conditions and the following disclaimer in the
     *    documentation and/or other materials provided with the distribution.
     * 3. Neither the name of the University nor the names of its contributors
     *    may be used to endorse or promote products derived from this software
     *    without specific prior written permission.
     *
     * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     * SUCH DAMAGE.
     *
     *      @(#)union.h     8.9 (Berkeley) 12/10/94
     * $FreeBSD$
     */
    
    #ifdef _KERNEL
    
    /* copy method of attr from lower to upper */
    typedef enum _unionfs_copymode {
            UNIONFS_TRADITIONAL = 0,
            UNIONFS_TRANSPARENT,
            UNIONFS_MASQUERADE
    } unionfs_copymode;
    
    /* whiteout policy of upper layer */
    typedef enum _unionfs_whitemode {
           UNIONFS_WHITE_ALWAYS = 0,
           UNIONFS_WHITE_WHENNEEDED
    } unionfs_whitemode;
    
    struct unionfs_mount {
            struct vnode   *um_lowervp;     /* VREFed once */
            struct vnode   *um_uppervp;     /* VREFed once */
            struct vnode   *um_rootvp;      /* ROOT vnode */
            struct mount_upper_node um_lower_link;  /* node in lower FS list of uppers */
            struct mount_upper_node um_upper_link;  /* node in upper FS list of uppers */
            unionfs_copymode um_copymode;
            unionfs_whitemode um_whitemode;
            uid_t           um_uid;
            gid_t           um_gid;
            u_short         um_udir;
            u_short         um_ufile;
    };
    
    /* unionfs status list */
    struct unionfs_node_status {
            LIST_ENTRY(unionfs_node_status) uns_list;       /* Status list */
            pid_t           uns_pid;                /* current process id */
            int             uns_node_flag;          /* uns flag */
            int             uns_lower_opencnt;      /* open count of lower */
            int             uns_upper_opencnt;      /* open count of upper */
            int             uns_lower_openmode;     /* open mode of lower */
            int             uns_readdir_status;     /* read status of readdir */
    };
    
    /* union node status flags */
    #define UNS_OPENL_4_READDIR     0x01    /* open lower layer for readdir */
    
    /* A cache of vnode references */
    struct unionfs_node {
            struct vnode   *un_lowervp;             /* lower side vnode */
            struct vnode   *un_uppervp;             /* upper side vnode */
            struct vnode   *un_dvp;                 /* parent unionfs vnode */
            struct vnode   *un_vnode;               /* Back pointer */
            LIST_HEAD(, unionfs_node_status) un_unshead;
                                                    /* unionfs status head */
            LIST_HEAD(unionfs_node_hashhead, unionfs_node) *un_hashtbl;
                                                    /* dir vnode hash table */
            union {
                    LIST_ENTRY(unionfs_node) un_hash; /* hash list entry */
                    STAILQ_ENTRY(unionfs_node) un_rele; /* deferred release list */
            };
    
            char           *un_path;                /* path */
           int             un_pathlen;             /* strlen of path */
           int             un_flag;                /* unionfs node flag */
   };
   
   /*
    * unionfs node flags
    * It needs the vnode with exclusive lock, when changing the un_flag variable.
    */
   #define UNIONFS_OPENEXTL        0x01    /* openextattr (lower) */
   #define UNIONFS_OPENEXTU        0x02    /* openextattr (upper) */
   
   extern struct vop_vector unionfs_vnodeops;
   
   static inline struct unionfs_node *
   unionfs_check_vnode(struct vnode *vp, const char *file __unused,
       int line __unused)
   {
           /*
            * unionfs_lock() needs the NULL check here, as it explicitly
            * handles the case in which the vnode has been vgonel()'ed.
            */
           KASSERT(vp->v_op == &unionfs_vnodeops || vp->v_data == NULL,
               ("%s:%d: non-unionfs vnode %p", file, line, vp));
           return ((struct unionfs_node *)vp->v_data);
   }
   
   #define MOUNTTOUNIONFSMOUNT(mp) ((struct unionfs_mount *)((mp)->mnt_data))
   #define VTOUNIONFS(vp) unionfs_check_vnode(vp, __FILE__, __LINE__)
   #define UNIONFSTOV(xp) ((xp)->un_vnode)
   
   int     unionfs_init(struct vfsconf *);
   int     unionfs_uninit(struct vfsconf *);
   int     unionfs_nodeget(struct mount *, struct vnode *, struct vnode *,
               struct vnode *, struct vnode **, struct componentname *);
   void    unionfs_noderem(struct vnode *);
   void    unionfs_get_node_status(struct unionfs_node *, struct thread *,
               struct unionfs_node_status **);
   void    unionfs_tryrem_node_status(struct unionfs_node *,
               struct unionfs_node_status *);
   int     unionfs_check_rmdir(struct vnode *, struct ucred *, struct thread *td);
   int     unionfs_copyfile(struct unionfs_node *, int, struct ucred *,
               struct thread *);
   void    unionfs_create_uppervattr_core(struct unionfs_mount *, struct vattr *,
               struct vattr *, struct thread *);
   int     unionfs_create_uppervattr(struct unionfs_mount *, struct vnode *,
               struct vattr *, struct ucred *, struct thread *);
   int     unionfs_mkshadowdir(struct unionfs_mount *, struct vnode *,
               struct unionfs_node *, struct componentname *, struct thread *);
   int     unionfs_mkwhiteout(struct vnode *, struct componentname *,
               struct thread *, char *, int);
   int     unionfs_relookup(struct vnode *, struct vnode **,
               struct componentname *, struct componentname *, struct thread *,
               char *, int, u_long);
   int     unionfs_relookup_for_create(struct vnode *, struct componentname *,
               struct thread *);
   int     unionfs_relookup_for_delete(struct vnode *, struct componentname *,
               struct thread *);
   int     unionfs_relookup_for_rename(struct vnode *, struct componentname *,
               struct thread *);
   
   #define UNIONFSVPTOLOWERVP(vp) (VTOUNIONFS(vp)->un_lowervp)
   #define UNIONFSVPTOUPPERVP(vp) (VTOUNIONFS(vp)->un_uppervp)
   
   #ifdef MALLOC_DECLARE
   MALLOC_DECLARE(M_UNIONFSNODE);
   MALLOC_DECLARE(M_UNIONFSPATH);
   #endif
   
   #ifdef UNIONFS_DEBUG
   #define UNIONFSDEBUG(format, args...) printf(format ,## args)
   #else
   #define UNIONFSDEBUG(format, args...)
   #endif                          /* UNIONFS_DEBUG */
   
   #endif                          /* _KERNEL */

Cache object: a3817314099adf759b92759ad4fa22a8