bsd/hfs/hfs_cnode.h

   1 /*
   2  * Copyright (c) 2002-2007 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 #ifndef _HFS_CNODE_H_
  29 #define _HFS_CNODE_H_
  30
  31 #include <sys/appleapiopts.h>
  32
  33 #ifdef KERNEL
  34 #ifdef __APPLE_API_PRIVATE
  35 #include <sys/types.h>
  36 #include <sys/queue.h>
  37 #include <sys/stat.h>
  38 #include <sys/vnode.h>
  39 #include <sys/quota.h>
  40
  41 #include <kern/locks.h>
  42
  43 #include <hfs/hfs_catalog.h>
  44 #include <hfs/rangelist.h>
  45
  46
  47 /*
  48  * The filefork is used to represent an HFS file fork (data or resource).
  49  * Reading or writing any of these fields requires holding cnode lock.
  50  */
  51 struct filefork {
  52         struct cnode   *ff_cp;               /* cnode associated with this fork */
  53         struct rl_head  ff_invalidranges;    /* Areas of disk that should read back as zeroes */
  54         union {
  55            void        *ffu_sysfileinfo;     /* additional info for system files */
  56            char        *ffu_symlinkptr;      /* symbolic link pathname */
  57         } ff_union;
  58         struct cat_fork ff_data;             /* fork data (size, extents) */
  59 };
  60 typedef struct filefork filefork_t;
  61
  62 /* Aliases for common fields */
  63 #define ff_size          ff_data.cf_size
  64 #define ff_clumpsize     ff_data.cf_clump
  65 #define ff_bytesread     ff_data.cf_bytesread
  66 #define ff_blocks        ff_data.cf_blocks
  67 #define ff_extents       ff_data.cf_extents
  68 #define ff_unallocblocks ff_data.cf_vblocks
  69
  70 #define ff_symlinkptr    ff_union.ffu_symlinkptr
  71 #define ff_sysfileinfo   ff_union.ffu_sysfileinfo
  72
  73
  74 /* The btree code still needs these... */
  75 #define fcbEOF           ff_size
  76 #define fcbExtents       ff_extents
  77 #define fcbBTCBPtr       ff_sysfileinfo
  78
  79 typedef u_int8_t atomicflag_t;
  80
  81
  82 /*
  83  * Hardlink Origin (for hardlinked directories).
  84  */
  85 struct linkorigin {
  86         TAILQ_ENTRY(linkorigin)  lo_link;  /* chain */
  87         void *  lo_thread;      /* thread that performed the lookup */
  88         cnid_t  lo_cnid;        /* hardlink's cnid */
  89         cnid_t  lo_parentcnid;  /* hardlink's parent cnid */
  90 };
  91 typedef struct linkorigin linkorigin_t;
  92
  93 #define MAX_CACHED_ORIGINS  10
  94 #define MAX_CACHED_FILE_ORIGINS 8
  95
  96 /*
  97  * The cnode is used to represent each active (or recently active)
  98  * file or directory in the HFS filesystem.
  99  *
 100  * Reading or writing any of these fields requires holding c_lock.
 101  */
 102 struct cnode {
 103         lck_rw_t                c_rwlock;       /* cnode's lock */
 104         void *                  c_lockowner;    /* cnode's lock owner (exclusive case only) */
 105         lck_rw_t                c_truncatelock; /* protects file from truncation during read/write */
 106         LIST_ENTRY(cnode)       c_hash;         /* cnode's hash chain */
 107         u_int32_t               c_flag;         /* cnode's runtime flags */
 108         u_int32_t               c_hflag;        /* cnode's flags for maintaining hash - protected by global hash lock */
 109         struct vnode            *c_vp;          /* vnode for data fork or dir */
 110         struct vnode            *c_rsrc_vp;     /* vnode for resource fork */
 111         dev_t                   c_dev;          /* cnode's device */
 112         struct dquot            *c_dquot[MAXQUOTAS]; /* cnode's quota info */
 113         struct klist            c_knotes;       /* knotes attached to this vnode */
 114         u_int32_t               c_childhint;     /* catalog hint for children (small dirs only) */
 115         u_int32_t               c_dirthreadhint; /* catalog hint for directory's thread rec */
 116         struct cat_desc         c_desc;         /* cnode's descriptor */
 117         struct cat_attr         c_attr;         /* cnode's attributes */
 118         TAILQ_HEAD(hfs_originhead, linkorigin) c_originlist;  /* hardlink origin cache */
 119         TAILQ_HEAD(hfs_hinthead, directoryhint) c_hintlist;  /* readdir directory hint list */
 120         int16_t                 c_dirhinttag;   /* directory hint tag */
 121         union {
 122             int16_t     cu_dirhintcnt;          /* directory hint count */
 123             int16_t     cu_syslockcount;        /* system file use only */
 124         } c_union;
 125         u_int32_t               c_dirchangecnt; /* changes each insert/delete (in-core only) */
 126         struct filefork         *c_datafork;    /* cnode's data fork */
 127         struct filefork         *c_rsrcfork;    /* cnode's rsrc fork */
 128         atomicflag_t    c_touch_acctime;
 129         atomicflag_t    c_touch_chgtime;
 130         atomicflag_t    c_touch_modtime;
 131 };
 132 typedef struct cnode cnode_t;
 133
 134 /* Aliases for common cnode fields */
 135 #define c_cnid          c_desc.cd_cnid
 136 #define c_hint          c_desc.cd_hint
 137 #define c_parentcnid    c_desc.cd_parentcnid
 138 #define c_encoding      c_desc.cd_encoding
 139
 140 #define c_fileid        c_attr.ca_fileid
 141 #define c_mode          c_attr.ca_mode
 142 #define c_linkcount     c_attr.ca_linkcount
 143 #define c_uid           c_attr.ca_uid
 144 #define c_gid           c_attr.ca_gid
 145 #define c_rdev          c_attr.ca_union1.cau_rdev
 146 #define c_atime         c_attr.ca_atime
 147 #define c_mtime         c_attr.ca_mtime
 148 #define c_ctime         c_attr.ca_ctime
 149 #define c_itime         c_attr.ca_itime
 150 #define c_btime         c_attr.ca_btime
 151 #define c_flags         c_attr.ca_flags
 152 #define c_finderinfo    c_attr.ca_finderinfo
 153 #define c_blocks        c_attr.ca_union2.cau_blocks
 154 #define c_entries       c_attr.ca_union2.cau_entries
 155 #define c_zftimeout     c_childhint
 156
 157 #define c_dirhintcnt    c_union.cu_dirhintcnt
 158 #define c_syslockcount  c_union.cu_syslockcount
 159
 160
 161 /* hash maintenance flags kept in c_hflag and protected by hfs_chash_mutex */
 162 #define H_ALLOC         0x00001 /* CNode is being allocated */
 163 #define H_ATTACH        0x00002 /* CNode is being attached to by another vnode */
 164 #define H_TRANSIT       0x00004 /* CNode is getting recycled  */
 165 #define H_WAITING       0x00008 /* CNode is being waited for */
 166
 167
 168 /* Runtime cnode flags (kept in c_flag) */
 169 #define C_NEED_RVNODE_PUT  0x00001  /* Need to do a vnode_put on c_rsrc_vp after the unlock */
 170 #define C_NEED_DVNODE_PUT  0x00002  /* Need to do a vnode_put on c_vp after the unlock */
 171 #define C_ZFWANTSYNC       0x00004  /* fsync requested and file has holes */
 172 #define C_FROMSYNC         0x00008  /* fsync was called from sync */
 173
 174 #define C_MODIFIED         0x00010  /* CNode has been modified */
 175 #define C_NOEXISTS         0x00020  /* CNode has been deleted, catalog entry is gone */
 176 #define C_DELETED          0x00040  /* CNode has been marked to be deleted */
 177 #define C_HARDLINK         0x00080  /* CNode is a hard link (file or dir) */
 178
 179 #define C_FORCEUPDATE      0x00100  /* force the catalog entry update */
 180 #define C_HASXATTRS        0x00200  /* cnode has extended attributes */
 181 #define C_NEG_ENTRIES      0x00400  /* directory has negative name entries */
 182 #define C_WARNED_RSRC      0x00800  /* cnode lookup warning has been issued */
 183
 184 #define C_NEED_DATA_SETSIZE  0x01000  /* Do a ubc_setsize(0) on c_rsrc_vp after the unlock */
 185 #define C_NEED_RSRC_SETSIZE  0x02000  /* Do a ubc_setsize(0) on c_vp after the unlock */
 186 #define C_DIR_MODIFICATION   0x04000  /* Directory is being modified, wait for lookups */
 187
 188 #define ZFTIMELIMIT     (5 * 60)
 189
 190 /*
 191  * The following is the "invisible" bit from the fdFlags field
 192  * in the FndrFileInfo.
 193  */
 194 enum { kFinderInvisibleMask = 1 << 14 };
 195
 196
 197 /*
 198  * Convert between cnode pointers and vnode pointers
 199  */
 200 #define VTOC(vp)        ((struct cnode *)vnode_fsnode((vp)))
 201
 202 #define CTOV(cp,rsrc)   (((rsrc) && S_ISREG((cp)->c_mode)) ? \
 203                         (cp)->c_rsrc_vp : (cp)->c_vp)
 204
 205 /*
 206  * Convert between vnode pointers and file forks
 207  *
 208  * Note: no CTOF since that is ambiguous
 209  */
 210
 211 #define FTOC(fp)        ((fp)->ff_cp)
 212
 213 #define VTOF(vp)        ((vp) == VTOC((vp))->c_rsrc_vp ?        \
 214                          VTOC((vp))->c_rsrcfork :               \
 215                          VTOC((vp))->c_datafork)
 216
 217 #define VCTOF(vp, cp)   ((vp) == (cp)->c_rsrc_vp ?      \
 218                          (cp)->c_rsrcfork :             \
 219                          (cp)->c_datafork)
 220
 221 #define FTOV(fp)        ((fp) == FTOC(fp)->c_rsrcfork ?         \
 222                          FTOC(fp)->c_rsrc_vp :                  \
 223                          FTOC(fp)->c_vp)
 224
 225
 226 /*
 227  * Test for a resource fork
 228  */
 229 #define FORK_IS_RSRC(fp)        ((fp) == FTOC(fp)->c_rsrcfork)
 230
 231 #define VNODE_IS_RSRC(vp)       ((vp) == VTOC((vp))->c_rsrc_vp)
 232
 233
 234 #define ATIME_ONDISK_ACCURACY   300
 235
 236
 237 /* This overlays the FileID portion of NFS file handles. */
 238 struct hfsfid {
 239         u_int32_t hfsfid_cnid;  /* Catalog node ID. */
 240         u_int32_t hfsfid_gen;   /* Generation number (create date). */
 241 };
 242
 243
 244 /* Get new default vnode */
 245 extern int hfs_getnewvnode(struct hfsmount *hfsmp, struct vnode *dvp, struct componentname *cnp,
 246                            struct cat_desc *descp, int flags, struct cat_attr *attrp,
 247                            struct cat_fork *forkp, struct vnode **vpp);
 248
 249
 250 #define GNV_WANTRSRC   0x01  /* Request the resource fork vnode. */
 251 #define GNV_SKIPLOCK   0x02  /* Skip taking the cnode lock (when getting resource fork). */
 252 #define GNV_CREATE     0x04  /* The vnode is for a newly created item. */
 253
 254
 255 /* Touch cnode times based on c_touch_xxx flags */
 256 extern void hfs_touchtimes(struct hfsmount *, struct cnode *);
 257
 258 /*
 259  * HFS cnode hash functions.
 260  */
 261 extern void  hfs_chashinit(void);
 262 extern void  hfs_chashinit_finish(void);
 263 extern void  hfs_chashinsert(struct cnode *cp);
 264 extern int   hfs_chashremove(struct cnode *cp);
 265 extern void  hfs_chash_abort(struct cnode *cp);
 266 extern void  hfs_chash_rehash(struct cnode *cp1, struct cnode *cp2);
 267 extern void  hfs_chashwakeup(struct cnode *cp, int flags);
 268 extern void  hfs_chash_mark_in_transit(struct cnode *cp);
 269
 270 extern struct vnode * hfs_chash_getvnode(dev_t dev, ino_t inum, int wantrsrc, int skiplock);
 271 extern struct cnode * hfs_chash_getcnode(dev_t dev, ino_t inum, struct vnode **vpp, int wantrsrc, int skiplock);
 272 extern int hfs_chash_snoop(dev_t, ino_t, int (*)(const struct cat_desc *,
 273                             const struct cat_attr *, void *), void *);
 274 extern int hfs_valid_cnode(struct hfsmount *hfsmp, struct vnode *dvp, struct componentname *cnp, cnid_t cnid);
 275
 276 extern int hfs_chash_set_childlinkbit(dev_t dev, cnid_t cnid);
 277
 278 /*
 279  * HFS cnode lock functions.
 280  *
 281  *  HFS Locking Order:
 282  *
 283  *  1. cnode truncate lock (if needed)
 284  *  2. cnode lock (in parent-child order if related, otherwise by address order)
 285  *  3. journal (if needed)
 286  *  4. system files (as needed)
 287  *       A. Catalog B-tree file
 288  *       B. Attributes B-tree file
 289  *       C. Startup file (if there is one)
 290  *       D. Allocation Bitmap file (always exclusive, supports recursion)
 291  *       E. Overflow Extents B-tree file (always exclusive, supports recursion)
 292  *  5. hfs mount point (always last)
 293  *
 294  */
 295 enum hfslocktype  {HFS_SHARED_LOCK = 1, HFS_EXCLUSIVE_LOCK = 2, HFS_FORCE_LOCK = 3};
 296 #define HFS_SHARED_OWNER  (void *)0xffffffff
 297
 298 extern int hfs_lock(struct cnode *, enum hfslocktype);
 299 extern int hfs_lockpair(struct cnode *, struct cnode *, enum hfslocktype);
 300 extern int hfs_lockfour(struct cnode *, struct cnode *, struct cnode *, struct cnode *,
 301                         enum hfslocktype);
 302
 303 extern void hfs_unlock(struct cnode *);
 304 extern void hfs_unlockpair(struct cnode *, struct cnode *);
 305 extern void hfs_unlockfour(struct cnode *, struct cnode *, struct cnode *, struct cnode *);
 306
 307 extern void hfs_lock_truncate(struct cnode *, int);
 308 extern void hfs_unlock_truncate(struct cnode *, int);
 309
 310 #endif /* __APPLE_API_PRIVATE */
 311 #endif /* KERNEL */
 312
 313 #endif /* ! _HFS_CNODE_H_ */