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 mount *um_lowermp; /* MNT_REFed lower mount object */ 55 struct mount *um_uppermp; /* MNT_REFed upper mount object */ 56 struct vnode *um_lowervp; /* VREFed once */ 57 struct vnode *um_uppervp; /* VREFed once */ 58 struct vnode *um_rootvp; /* ROOT vnode */ 59 struct mount_upper_node um_lower_link; /* node in lower FS list of uppers */ 60 struct mount_upper_node um_upper_link; /* node in upper FS list of uppers */ 61 unionfs_copymode um_copymode; 62 unionfs_whitemode um_whitemode; 63 uid_t um_uid; 64 gid_t um_gid; 65 u_short um_udir; 66 u_short um_ufile; 67 }; 68 69 /* unionfs status list */ 70 struct unionfs_node_status { 71 LIST_ENTRY(unionfs_node_status) uns_list; /* Status list */ 72 pid_t uns_pid; /* current process id */ 73 int uns_node_flag; /* uns flag */ 74 int uns_lower_opencnt; /* open count of lower */ 75 int uns_upper_opencnt; /* open count of upper */ 76 int uns_lower_openmode; /* open mode of lower */ 77 int uns_readdir_status; /* read status of readdir */ 78 }; 79 80 /* union node status flags */ 81 #define UNS_OPENL_4_READDIR 0x01 /* open lower layer for readdir */ 82 83 /* A cache of vnode references */ 84 struct unionfs_node { 85 struct vnode *un_lowervp; /* lower side vnode */ 86 struct vnode *un_uppervp; /* upper side vnode */ 87 struct vnode *un_dvp; /* parent unionfs vnode */ 88 struct vnode *un_vnode; /* Back pointer */ 89 LIST_HEAD(, unionfs_node_status) un_unshead; 90 /* unionfs status head */ 91 LIST_HEAD(unionfs_node_hashhead, unionfs_node) *un_hashtbl; 92 /* dir vnode hash table */ 93 union { 94 LIST_ENTRY(unionfs_node) un_hash; /* hash list entry */ 95 STAILQ_ENTRY(unionfs_node) un_rele; /* deferred release list */ 96 }; 97 98 char *un_path; /* path */ 99 int un_pathlen; /* strlen of path */ 100 int un_flag; /* unionfs node flag */ 101 }; 102 103 /* 104 * unionfs node flags 105 * It needs the vnode with exclusive lock, when changing the un_flag variable. 106 */ 107 #define UNIONFS_OPENEXTL 0x01 /* openextattr (lower) */ 108 #define UNIONFS_OPENEXTU 0x02 /* openextattr (upper) */ 109 110 extern struct vop_vector unionfs_vnodeops; 111 112 static inline struct unionfs_node * 113 unionfs_check_vnode(struct vnode *vp, const char *file __unused, 114 int line __unused) 115 { 116 /* 117 * unionfs_lock() needs the NULL check here, as it explicitly 118 * handles the case in which the vnode has been vgonel()'ed. 119 */ 120 KASSERT(vp->v_op == &unionfs_vnodeops || vp->v_data == NULL, 121 ("%s:%d: non-unionfs vnode %p", file, line, vp)); 122 return ((struct unionfs_node *)vp->v_data); 123 } 124 125 #define MOUNTTOUNIONFSMOUNT(mp) ((struct unionfs_mount *)((mp)->mnt_data)) 126 #define VTOUNIONFS(vp) unionfs_check_vnode(vp, __FILE__, __LINE__) 127 #define UNIONFSTOV(xp) ((xp)->un_vnode) 128 129 int unionfs_init(struct vfsconf *); 130 int unionfs_uninit(struct vfsconf *); 131 int unionfs_nodeget(struct mount *, struct vnode *, struct vnode *, 132 struct vnode *, struct vnode **, struct componentname *); 133 void unionfs_noderem(struct vnode *); 134 void unionfs_get_node_status(struct unionfs_node *, struct thread *, 135 struct unionfs_node_status **); 136 void unionfs_tryrem_node_status(struct unionfs_node *, 137 struct unionfs_node_status *); 138 int unionfs_check_rmdir(struct vnode *, struct ucred *, struct thread *td); 139 int unionfs_copyfile(struct unionfs_node *, int, struct ucred *, 140 struct thread *); 141 void unionfs_create_uppervattr_core(struct unionfs_mount *, struct vattr *, 142 struct vattr *, struct thread *); 143 int unionfs_create_uppervattr(struct unionfs_mount *, struct vnode *, 144 struct vattr *, struct ucred *, struct thread *); 145 int unionfs_mkshadowdir(struct unionfs_mount *, struct vnode *, 146 struct unionfs_node *, struct componentname *, struct thread *); 147 int unionfs_mkwhiteout(struct vnode *, struct vnode *, 148 struct componentname *, struct thread *, char *, int); 149 int unionfs_relookup(struct vnode *, struct vnode **, 150 struct componentname *, struct componentname *, struct thread *, 151 char *, int, u_long); 152 int unionfs_relookup_for_create(struct vnode *, struct componentname *, 153 struct thread *); 154 int unionfs_relookup_for_delete(struct vnode *, struct componentname *, 155 struct thread *); 156 int unionfs_relookup_for_rename(struct vnode *, struct componentname *, 157 struct thread *); 158 void unionfs_forward_vop_start_pair(struct vnode *, int *, 159 struct vnode *, int *); 160 bool unionfs_forward_vop_finish_pair(struct vnode *, struct vnode *, int, 161 struct vnode *, struct vnode *, int); 162 163 static inline void 164 unionfs_forward_vop_start(struct vnode *basevp, int *lkflags) 165 { 166 unionfs_forward_vop_start_pair(basevp, lkflags, NULL, NULL); 167 } 168 169 static inline bool 170 unionfs_forward_vop_finish(struct vnode *unionvp, struct vnode *basevp, 171 int lkflags) 172 { 173 return (unionfs_forward_vop_finish_pair(unionvp, basevp, lkflags, 174 NULL, NULL, 0)); 175 } 176 177 #define UNIONFSVPTOLOWERVP(vp) (VTOUNIONFS(vp)->un_lowervp) 178 #define UNIONFSVPTOUPPERVP(vp) (VTOUNIONFS(vp)->un_uppervp) 179 180 #ifdef MALLOC_DECLARE 181 MALLOC_DECLARE(M_UNIONFSNODE); 182 MALLOC_DECLARE(M_UNIONFSPATH); 183 #endif 184 185 #ifdef UNIONFS_DEBUG 186 #define UNIONFSDEBUG(format, args...) printf(format ,## args) 187 #else 188 #define UNIONFSDEBUG(format, args...) 189 #endif /* UNIONFS_DEBUG */ 190 191 #endif /* _KERNEL */ 192