1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1994 The Regents of the University of California. 5 * Copyright (c) 1994 Jan-Simon Pendry. 6 * Copyright (c) 2005, 2006 Masanori Ozawa <ozawa@ongs.co.jp>, ONGS Inc. 7 * Copyright (c) 2006 Daichi Goto <daichi@freebsd.org> 8 * All rights reserved. 9 * 10 * This code is derived from software donated to Berkeley by 11 * Jan-Simon Pendry. 12 * 13 * Redistribution and use in source and binary forms, with or without 14 * modification, are permitted provided that the following conditions 15 * are met: 16 * 1. Redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer. 18 * 2. Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution. 21 * 3. Neither the name of the University nor the names of its contributors 22 * may be used to endorse or promote products derived from this software 23 * without specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35 * SUCH DAMAGE. 36 */ 37 38 #ifdef _KERNEL 39 40 /* copy method of attr from lower to upper */ 41 typedef enum _unionfs_copymode { 42 UNIONFS_TRADITIONAL = 0, 43 UNIONFS_TRANSPARENT, 44 UNIONFS_MASQUERADE 45 } unionfs_copymode; 46 47 /* whiteout policy of upper layer */ 48 typedef enum _unionfs_whitemode { 49 UNIONFS_WHITE_ALWAYS = 0, 50 UNIONFS_WHITE_WHENNEEDED 51 } unionfs_whitemode; 52 53 struct unionfs_mount { 54 struct vnode *um_lowervp; /* VREFed once */ 55 struct vnode *um_uppervp; /* VREFed once */ 56 struct vnode *um_rootvp; /* ROOT vnode */ 57 struct mount_upper_node um_lower_link; /* node in lower FS list of uppers */ 58 struct mount_upper_node um_upper_link; /* node in upper FS list of uppers */ 59 unionfs_copymode um_copymode; 60 unionfs_whitemode um_whitemode; 61 uid_t um_uid; 62 gid_t um_gid; 63 u_short um_udir; 64 u_short um_ufile; 65 }; 66 67 /* unionfs status list */ 68 struct unionfs_node_status { 69 LIST_ENTRY(unionfs_node_status) uns_list; /* Status list */ 70 pid_t uns_pid; /* current process id */ 71 int uns_node_flag; /* uns flag */ 72 int uns_lower_opencnt; /* open count of lower */ 73 int uns_upper_opencnt; /* open count of upper */ 74 int uns_lower_openmode; /* open mode of lower */ 75 int uns_readdir_status; /* read status of readdir */ 76 }; 77 78 /* union node status flags */ 79 #define UNS_OPENL_4_READDIR 0x01 /* open lower layer for readdir */ 80 81 /* A cache of vnode references */ 82 struct unionfs_node { 83 struct vnode *un_lowervp; /* lower side vnode */ 84 struct vnode *un_uppervp; /* upper side vnode */ 85 struct vnode *un_dvp; /* parent unionfs vnode */ 86 struct vnode *un_vnode; /* Back pointer */ 87 LIST_HEAD(, unionfs_node_status) un_unshead; 88 /* unionfs status head */ 89 LIST_HEAD(unionfs_node_hashhead, unionfs_node) *un_hashtbl; 90 /* dir vnode hash table */ 91 union { 92 LIST_ENTRY(unionfs_node) un_hash; /* hash list entry */ 93 STAILQ_ENTRY(unionfs_node) un_rele; /* deferred release list */ 94 }; 95 96 char *un_path; /* path */ 97 int un_pathlen; /* strlen of path */ 98 int un_flag; /* unionfs node flag */ 99 }; 100 101 /* 102 * unionfs node flags 103 * It needs the vnode with exclusive lock, when changing the un_flag variable. 104 */ 105 #define UNIONFS_OPENEXTL 0x01 /* openextattr (lower) */ 106 #define UNIONFS_OPENEXTU 0x02 /* openextattr (upper) */ 107 108 extern struct vop_vector unionfs_vnodeops; 109 110 static inline struct unionfs_node * 111 unionfs_check_vnode(struct vnode *vp, const char *file __unused, 112 int line __unused) 113 { 114 /* 115 * unionfs_lock() needs the NULL check here, as it explicitly 116 * handles the case in which the vnode has been vgonel()'ed. 117 */ 118 KASSERT(vp->v_op == &unionfs_vnodeops || vp->v_data == NULL, 119 ("%s:%d: non-unionfs vnode %p", file, line, vp)); 120 return ((struct unionfs_node *)vp->v_data); 121 } 122 123 #define MOUNTTOUNIONFSMOUNT(mp) ((struct unionfs_mount *)((mp)->mnt_data)) 124 #define VTOUNIONFS(vp) unionfs_check_vnode(vp, __FILE__, __LINE__) 125 #define UNIONFSTOV(xp) ((xp)->un_vnode) 126 127 int unionfs_init(struct vfsconf *); 128 int unionfs_uninit(struct vfsconf *); 129 int unionfs_nodeget(struct mount *, struct vnode *, struct vnode *, 130 struct vnode *, struct vnode **, struct componentname *); 131 void unionfs_noderem(struct vnode *); 132 void unionfs_get_node_status(struct unionfs_node *, struct thread *, 133 struct unionfs_node_status **); 134 void unionfs_tryrem_node_status(struct unionfs_node *, 135 struct unionfs_node_status *); 136 int unionfs_check_rmdir(struct vnode *, struct ucred *, struct thread *td); 137 int unionfs_copyfile(struct unionfs_node *, int, struct ucred *, 138 struct thread *); 139 void unionfs_create_uppervattr_core(struct unionfs_mount *, struct vattr *, 140 struct vattr *, struct thread *); 141 int unionfs_create_uppervattr(struct unionfs_mount *, struct vnode *, 142 struct vattr *, struct ucred *, struct thread *); 143 int unionfs_mkshadowdir(struct unionfs_mount *, struct vnode *, 144 struct unionfs_node *, struct componentname *, struct thread *); 145 int unionfs_mkwhiteout(struct vnode *, struct componentname *, 146 struct thread *, char *, int); 147 int unionfs_relookup(struct vnode *, struct vnode **, 148 struct componentname *, struct componentname *, struct thread *, 149 char *, int, u_long); 150 int unionfs_relookup_for_create(struct vnode *, struct componentname *, 151 struct thread *); 152 int unionfs_relookup_for_delete(struct vnode *, struct componentname *, 153 struct thread *); 154 int unionfs_relookup_for_rename(struct vnode *, struct componentname *, 155 struct thread *); 156 157 #define UNIONFSVPTOLOWERVP(vp) (VTOUNIONFS(vp)->un_lowervp) 158 #define UNIONFSVPTOUPPERVP(vp) (VTOUNIONFS(vp)->un_uppervp) 159 160 #ifdef MALLOC_DECLARE 161 MALLOC_DECLARE(M_UNIONFSNODE); 162 MALLOC_DECLARE(M_UNIONFSPATH); 163 #endif 164 165 #ifdef UNIONFS_DEBUG 166 #define UNIONFSDEBUG(format, args...) printf(format ,## args) 167 #else 168 #define UNIONFSDEBUG(format, args...) 169 #endif /* UNIONFS_DEBUG */ 170 171 #endif /* _KERNEL */ 172