bsd/hfs/hfs_cnode.h

   1 /*
   2  * Copyright (c) 2002-2008 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 #if HFS_COMPRESSION
  46 #include <sys/decmpfs.h>
  47 #endif
  48 #if CONFIG_PROTECT
  49 #include <sys/cprotect.h>
  50 #endif
  51
  52
  53 /*
  54  * The filefork is used to represent an HFS file fork (data or resource).
  55  * Reading or writing any of these fields requires holding cnode lock.
  56  */
  57 struct filefork {
  58         struct cnode   *ff_cp;               /* cnode associated with this fork */
  59         struct rl_head  ff_invalidranges;    /* Areas of disk that should read back as zeroes */
  60         union {
  61            void        *ffu_sysfileinfo;     /* additional info for system files */
  62            char        *ffu_symlinkptr;      /* symbolic link pathname */
  63         } ff_union;
  64         struct cat_fork ff_data;             /* fork data (size, extents) */
  65 };
  66 typedef struct filefork filefork_t;
  67
  68 /* Aliases for common fields */
  69 #define ff_size          ff_data.cf_size
  70 #define ff_new_size      ff_data.cf_new_size
  71 #define ff_clumpsize     ff_data.cf_clump
  72 #define ff_bytesread     ff_data.cf_bytesread
  73 #define ff_blocks        ff_data.cf_blocks
  74 #define ff_extents       ff_data.cf_extents
  75 #define ff_unallocblocks ff_data.cf_vblocks
  76
  77 #define ff_symlinkptr    ff_union.ffu_symlinkptr
  78 #define ff_sysfileinfo   ff_union.ffu_sysfileinfo
  79
  80
  81 /* The btree code still needs these... */
  82 #define fcbEOF           ff_size
  83 #define fcbExtents       ff_extents
  84 #define fcbBTCBPtr       ff_sysfileinfo
  85
  86 typedef u_int8_t atomicflag_t;
  87
  88
  89 /*
  90  * Hardlink Origin (for hardlinked directories).
  91  */
  92 struct linkorigin {
  93         TAILQ_ENTRY(linkorigin)  lo_link;  /* chain */
  94         void *  lo_thread;      /* thread that performed the lookup */
  95         cnid_t  lo_cnid;        /* hardlink's cnid */
  96         cnid_t  lo_parentcnid;  /* hardlink's parent cnid */
  97 };
  98 typedef struct linkorigin linkorigin_t;
  99
 100 #define MAX_CACHED_ORIGINS  10
 101 #define MAX_CACHED_FILE_ORIGINS 8
 102
 103 /*
 104  * The cnode is used to represent each active (or recently active)
 105  * file or directory in the HFS filesystem.
 106  *
 107  * Reading or writing any of these fields requires holding c_lock.
 108  */
 109 struct cnode {
 110         lck_rw_t                c_rwlock;       /* cnode's lock */
 111         void *                  c_lockowner;    /* cnode's lock owner (exclusive case only) */
 112         lck_rw_t                c_truncatelock; /* protects file from truncation during read/write */
 113         void *                  c_truncatelockowner;    /* truncate lock owner (exclusive case only) */
 114         LIST_ENTRY(cnode)       c_hash;         /* cnode's hash chain */
 115         u_int32_t               c_flag;         /* cnode's runtime flags */
 116         u_int32_t               c_hflag;        /* cnode's flags for maintaining hash - protected by global hash lock */
 117         struct vnode            *c_vp;          /* vnode for data fork or dir */
 118         struct vnode            *c_rsrc_vp;     /* vnode for resource fork */
 119     struct dquot                *c_dquot[MAXQUOTAS]; /* cnode's quota info */
 120         u_int32_t               c_childhint;     /* catalog hint for children (small dirs only) */
 121         u_int32_t               c_dirthreadhint; /* catalog hint for directory's thread rec */
 122         struct cat_desc         c_desc;         /* cnode's descriptor */
 123         struct cat_attr         c_attr;         /* cnode's attributes */
 124         TAILQ_HEAD(hfs_originhead, linkorigin) c_originlist;  /* hardlink origin cache */
 125         TAILQ_HEAD(hfs_hinthead, directoryhint) c_hintlist;  /* readdir directory hint list */
 126         int16_t                 c_dirhinttag;   /* directory hint tag */
 127         union {
 128             int16_t     cu_dirhintcnt;          /* directory hint count */
 129             int16_t     cu_syslockcount;        /* system file use only */
 130         } c_union;
 131         u_int32_t               c_dirchangecnt; /* changes each insert/delete (in-core only) */
 132         struct filefork         *c_datafork;    /* cnode's data fork */
 133         struct filefork         *c_rsrcfork;    /* cnode's rsrc fork */
 134         atomicflag_t    c_touch_acctime;
 135         atomicflag_t    c_touch_chgtime;
 136         atomicflag_t    c_touch_modtime;
 137 #if HFS_COMPRESSION
 138         decmpfs_cnode  *c_decmp;
 139 #endif /* HFS_COMPRESSION */
 140 #if CONFIG_PROTECT
 141         cprotect_t              c_cpentry;      /* content protection data */
 142 #endif
 143
 144 };
 145 typedef struct cnode cnode_t;
 146
 147 /* Aliases for common cnode fields */
 148 #define c_cnid          c_desc.cd_cnid
 149 #define c_hint          c_desc.cd_hint
 150 #define c_parentcnid    c_desc.cd_parentcnid
 151 #define c_encoding      c_desc.cd_encoding
 152
 153 #define c_fileid        c_attr.ca_fileid
 154 #define c_mode          c_attr.ca_mode
 155 #define c_linkcount     c_attr.ca_linkcount
 156 #define c_uid           c_attr.ca_uid
 157 #define c_gid           c_attr.ca_gid
 158 #define c_rdev          c_attr.ca_union1.cau_rdev
 159 #define c_atime         c_attr.ca_atime
 160 #define c_mtime         c_attr.ca_mtime
 161 #define c_ctime         c_attr.ca_ctime
 162 #define c_itime         c_attr.ca_itime
 163 #define c_btime         c_attr.ca_btime
 164 #define c_flags         c_attr.ca_flags
 165 #define c_finderinfo    c_attr.ca_finderinfo
 166 #define c_blocks        c_attr.ca_union2.cau_blocks
 167 #define c_entries       c_attr.ca_union2.cau_entries
 168 #define c_zftimeout     c_childhint
 169
 170 #define c_dirhintcnt    c_union.cu_dirhintcnt
 171 #define c_syslockcount  c_union.cu_syslockcount
 172
 173
 174 /* hash maintenance flags kept in c_hflag and protected by hfs_chash_mutex */
 175 #define H_ALLOC         0x00001 /* CNode is being allocated */
 176 #define H_ATTACH        0x00002 /* CNode is being attached to by another vnode */
 177 #define H_TRANSIT       0x00004 /* CNode is getting recycled  */
 178 #define H_WAITING       0x00008 /* CNode is being waited for */
 179
 180
 181 /* Runtime cnode flags (kept in c_flag) */
 182 #define C_NEED_RVNODE_PUT  0x00001  /* Need to do a vnode_put on c_rsrc_vp after the unlock */
 183 #define C_NEED_DVNODE_PUT  0x00002  /* Need to do a vnode_put on c_vp after the unlock */
 184 #define C_ZFWANTSYNC       0x00004  /* fsync requested and file has holes */
 185 #define C_FROMSYNC         0x00008  /* fsync was called from sync */
 186
 187 #define C_MODIFIED         0x00010  /* CNode has been modified */
 188 #define C_NOEXISTS         0x00020  /* CNode has been deleted, catalog entry is gone */
 189 #define C_DELETED          0x00040  /* CNode has been marked to be deleted */
 190 #define C_HARDLINK         0x00080  /* CNode is a hard link (file or dir) */
 191
 192 #define C_FORCEUPDATE      0x00100  /* force the catalog entry update */
 193 #define C_HASXATTRS        0x00200  /* cnode has extended attributes */
 194 #define C_NEG_ENTRIES      0x00400  /* directory has negative name entries */
 195 #define C_SWAPINPROGRESS   0x00800      /* cnode's data is about to be swapped.  Issue synchronous cluster io */
 196
 197 #define C_NEED_DATA_SETSIZE  0x01000  /* Do a ubc_setsize(0) on c_rsrc_vp after the unlock */
 198 #define C_NEED_RSRC_SETSIZE  0x02000  /* Do a ubc_setsize(0) on c_vp after the unlock */
 199 #define C_DIR_MODIFICATION   0x04000  /* Directory is being modified, wait for lookups */
 200 #define C_ALWAYS_ZEROFILL    0x08000  /* Always zero-fill the file on an fsync */
 201
 202 #define C_RENAMED                       0x10000 /* cnode was deleted as part of rename; C_DELETED should also be set */
 203 #define C_NEEDS_DATEADDED       0x20000 /* cnode needs date-added written to the finderinfo bit */
 204 #define C_BACKINGSTORE          0x40000 /* cnode is a backing store for an existing or currently-mounting filesystem */
 205 #define ZFTIMELIMIT     (5 * 60)
 206
 207 /*
 208  * The following is the "invisible" bit from the fdFlags field
 209  * in the FndrFileInfo.
 210  */
 211 enum { kFinderInvisibleMask = 1 << 14 };
 212
 213
 214 /*
 215  * Convert between cnode pointers and vnode pointers
 216  */
 217 #define VTOC(vp)        ((struct cnode *)vnode_fsnode((vp)))
 218
 219 #define CTOV(cp,rsrc)   (((rsrc) && S_ISREG((cp)->c_mode)) ? \
 220                         (cp)->c_rsrc_vp : (cp)->c_vp)
 221
 222 /*
 223  * Convert between vnode pointers and file forks
 224  *
 225  * Note: no CTOF since that is ambiguous
 226  */
 227
 228 #define FTOC(fp)        ((fp)->ff_cp)
 229
 230 #define VTOF(vp)        ((vp) == VTOC((vp))->c_rsrc_vp ?        \
 231                          VTOC((vp))->c_rsrcfork :               \
 232                          VTOC((vp))->c_datafork)
 233
 234 #define VCTOF(vp, cp)   ((vp) == (cp)->c_rsrc_vp ?      \
 235                          (cp)->c_rsrcfork :             \
 236                          (cp)->c_datafork)
 237
 238 #define FTOV(fp)        ((fp) == FTOC(fp)->c_rsrcfork ?         \
 239                          FTOC(fp)->c_rsrc_vp :                  \
 240                          FTOC(fp)->c_vp)
 241
 242 /*
 243  * This is a helper function used for determining whether or not a cnode has become open
 244  * unlinked in between the time we acquired its vnode and the time we acquire the cnode lock
 245  * to start manipulating it.  Due to the SMP nature of VFS, it is probably necessary to
 246  * use this macro every time we acquire a cnode lock, as the content of the Cnode may have
 247  * been modified in betweeen the lookup and a VNOP.  Whether or not to call this is dependent
 248  * upon the VNOP in question.  Sometimes it is OK to use an open-unlinked file, for example, in,
 249  * reading.  But other times, such as on the source of a VNOP_RENAME, it should be disallowed.
 250  */
 251 int hfs_checkdeleted(struct cnode *cp);
 252
 253 /*
 254  * Test for a resource fork
 255  */
 256 #define FORK_IS_RSRC(fp)        ((fp) == FTOC(fp)->c_rsrcfork)
 257
 258 #define VNODE_IS_RSRC(vp)       ((vp) == VTOC((vp))->c_rsrc_vp)
 259
 260 #if HFS_COMPRESSION
 261 /*
 262  * VTOCMP(vp) returns a pointer to vp's decmpfs_cnode; this could be NULL
 263  * if the file is not compressed or if hfs_file_is_compressed() hasn't
 264  * yet been called on this file.
 265  */
 266 #define VTOCMP(vp) (VTOC((vp))->c_decmp)
 267 int hfs_file_is_compressed(struct cnode *cp, int skiplock);
 268 int hfs_uncompressed_size_of_compressed_file(struct hfsmount *hfsmp, struct vnode *vp, cnid_t fid, off_t *size, int skiplock);
 269 int hfs_hides_rsrc(vfs_context_t ctx, struct cnode *cp, int skiplock);
 270 int hfs_hides_xattr(vfs_context_t ctx, struct cnode *cp, const char *name, int skiplock);
 271 #endif
 272
 273 #define ATIME_ONDISK_ACCURACY   300
 274
 275
 276 /* This overlays the FileID portion of NFS file handles. */
 277 struct hfsfid {
 278         u_int32_t hfsfid_cnid;  /* Catalog node ID. */
 279         u_int32_t hfsfid_gen;   /* Generation number (create date). */
 280 };
 281
 282
 283 /* Get new default vnode */
 284 extern int hfs_getnewvnode(struct hfsmount *hfsmp, struct vnode *dvp, struct componentname *cnp,
 285                            struct cat_desc *descp, int flags, struct cat_attr *attrp,
 286                            struct cat_fork *forkp, struct vnode **vpp, int *out_flags);
 287
 288 /* Input flags for hfs_getnewvnode */
 289
 290 #define GNV_WANTRSRC   0x01  /* Request the resource fork vnode. */
 291 #define GNV_SKIPLOCK   0x02  /* Skip taking the cnode lock (when getting resource fork). */
 292 #define GNV_CREATE     0x04  /* The vnode is for a newly created item. */
 293 #define GNV_NOCACHE        0x08  /* Delay entering this item in the name cache */
 294
 295 /* Output flags for hfs_getnewvnode */
 296 #define GNV_CHASH_RENAMED       0x01    /* The cnode was renamed in-flight */
 297 #define GNV_CAT_DELETED         0x02    /* The cnode was deleted from the catalog */
 298 #define GNV_NEW_CNODE           0x04    /* We are vending out a newly initialized cnode */
 299 #define GNV_CAT_ATTRCHANGED     0x08    /* Something in struct cat_attr changed in between cat_lookups */
 300
 301 /* Touch cnode times based on c_touch_xxx flags */
 302 extern void hfs_touchtimes(struct hfsmount *, struct cnode *);
 303 extern void hfs_write_dateadded (struct cat_attr *cattrp, u_int32_t dateadded);
 304 extern u_int32_t hfs_get_dateadded (struct cnode *cp);
 305
 306 /* Zero-fill file and push regions out to disk */
 307 extern int  hfs_filedone(struct vnode *vp, vfs_context_t context);
 308
 309 /*
 310  * HFS cnode hash functions.
 311  */
 312 extern void  hfs_chashinit(void);
 313 extern void  hfs_chashinit_finish(struct hfsmount *hfsmp);
 314 extern void  hfs_delete_chash(struct hfsmount *hfsmp);
 315 extern int   hfs_chashremove(struct hfsmount *hfsmp, struct cnode *cp);
 316 extern void  hfs_chash_abort(struct hfsmount *hfsmp, struct cnode *cp);
 317 extern void  hfs_chash_rehash(struct hfsmount *hfsmp, struct cnode *cp1, struct cnode *cp2);
 318 extern void  hfs_chashwakeup(struct hfsmount *hfsmp, struct cnode *cp, int flags);
 319 extern void  hfs_chash_mark_in_transit(struct hfsmount *hfsmp, struct cnode *cp);
 320
 321 extern struct vnode * hfs_chash_getvnode(struct hfsmount *hfsmp, ino_t inum, int wantrsrc,
 322                                                                                  int skiplock, int allow_deleted);
 323 extern struct cnode * hfs_chash_getcnode(struct hfsmount *hfsmp, ino_t inum, struct vnode **vpp,
 324                                                                                  int wantrsrc, int skiplock, int *out_flags, int *hflags);
 325 extern int hfs_chash_snoop(struct hfsmount *, ino_t, int (*)(const struct cat_desc *,
 326                             const struct cat_attr *, void *), void *);
 327 extern int hfs_valid_cnode(struct hfsmount *hfsmp, struct vnode *dvp, struct componentname *cnp,
 328                                                         cnid_t cnid, struct cat_attr *cattr, int *error);
 329
 330 extern int hfs_chash_set_childlinkbit(struct hfsmount *hfsmp, cnid_t cnid);
 331
 332 /*
 333  * HFS cnode lock functions.
 334  *
 335  *  HFS Locking Order:
 336  *
 337  *  1. cnode truncate lock (if needed)
 338  *  2. cnode lock (in parent-child order if related, otherwise by address order)
 339  *  3. journal (if needed)
 340  *  4. system files (as needed)
 341  *       A. Catalog B-tree file
 342  *       B. Attributes B-tree file
 343  *       C. Startup file (if there is one)
 344  *       D. Allocation Bitmap file (always exclusive, supports recursion)
 345  *       E. Overflow Extents B-tree file (always exclusive, supports recursion)
 346  *  5. hfs mount point (always last)
 347  *
 348  */
 349 enum hfslocktype  {HFS_SHARED_LOCK = 1, HFS_EXCLUSIVE_LOCK = 2, HFS_FORCE_LOCK = 3, HFS_RECURSE_TRUNCLOCK = 4};
 350 #define HFS_SHARED_OWNER  (void *)0xffffffff
 351
 352 int hfs_lock(struct cnode *, enum hfslocktype);
 353 int hfs_lockpair(struct cnode *, struct cnode *, enum hfslocktype);
 354 int hfs_lockfour(struct cnode *, struct cnode *, struct cnode *, struct cnode *,
 355                         enum hfslocktype, struct cnode **);
 356
 357 void hfs_unlock(struct cnode *);
 358 void hfs_unlockpair(struct cnode *, struct cnode *);
 359 void hfs_unlockfour(struct cnode *, struct cnode *, struct cnode *, struct cnode *);
 360
 361 void hfs_lock_truncate(struct cnode *, enum hfslocktype);
 362 void hfs_unlock_truncate(struct cnode *, int been_recursed);
 363
 364 int hfs_try_trunclock(struct cnode *, enum hfslocktype);
 365
 366 #endif /* __APPLE_API_PRIVATE */
 367 #endif /* KERNEL */
 368
 369 #endif /* ! _HFS_CNODE_H_ */