bsd/hfs/hfs_cnode.h

   1 /*
   2  * Copyright (c) 2002-2005 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 #ifndef _HFS_CNODE_H_
  23 #define _HFS_CNODE_H_
  24
  25 #include <sys/appleapiopts.h>
  26
  27 #ifdef KERNEL
  28 #ifdef __APPLE_API_PRIVATE
  29 #include <sys/types.h>
  30 #include <sys/queue.h>
  31 #include <sys/stat.h>
  32 #include <sys/vnode.h>
  33 #include <sys/quota.h>
  34
  35 #include <kern/locks.h>
  36
  37 #include <hfs/hfs_catalog.h>
  38 #include <hfs/rangelist.h>
  39
  40
  41 /*
  42  * The filefork is used to represent an HFS file fork (data or resource).
  43  * Reading or writing any of these fields requires holding cnode lock.
  44  */
  45 struct filefork {
  46         struct cnode   *ff_cp;               /* cnode associated with this fork */
  47         struct rl_head  ff_invalidranges;    /* Areas of disk that should read back as zeroes */
  48         union {
  49            void        *ffu_sysfileinfo;     /* additional info for system files */
  50            char        *ffu_symlinkptr;      /* symbolic link pathname */
  51         } ff_union;
  52         struct cat_fork ff_data;             /* fork data (size, extents) */
  53 };
  54 typedef struct filefork filefork_t;
  55
  56 /* Aliases for common fields */
  57 #define ff_size          ff_data.cf_size
  58 #define ff_clumpsize     ff_data.cf_clump
  59 #define ff_bytesread     ff_data.cf_bytesread
  60 #define ff_blocks        ff_data.cf_blocks
  61 #define ff_extents       ff_data.cf_extents
  62 #define ff_unallocblocks ff_data.cf_vblocks
  63
  64 #define ff_symlinkptr    ff_union.ffu_symlinkptr
  65 #define ff_sysfileinfo   ff_union.ffu_sysfileinfo
  66
  67
  68 /* The btree code still needs these... */
  69 #define fcbEOF           ff_size
  70 #define fcbExtents       ff_extents
  71 #define fcbBTCBPtr       ff_sysfileinfo
  72
  73 typedef u_int8_t atomicflag_t;
  74
  75 /*
  76  * The cnode is used to represent each active (or recently active)
  77  * file or directory in the HFS filesystem.
  78  *
  79  * Reading or writing any of these fields requires holding c_lock.
  80  */
  81 struct cnode {
  82         lck_rw_t                c_rwlock;       /* cnode's lock */
  83         void *                  c_lockowner;    /* cnode's lock owner (exclusive case only) */
  84         lck_rw_t                c_truncatelock; /* protects file from truncation during read/write */
  85         LIST_ENTRY(cnode)       c_hash;         /* cnode's hash chain */
  86         u_int32_t               c_flag;         /* cnode's runtime flags */
  87         u_int32_t               c_hflag;        /* cnode's flags for maintaining hash - protected by global hash lock */
  88         struct vnode            *c_vp;          /* vnode for data fork or dir */
  89         struct vnode            *c_rsrc_vp;     /* vnode for resource fork */
  90         struct vnode            *c_devvp;       /* vnode for block I/O */
  91         dev_t                   c_dev;          /* cnode's device */
  92         struct dquot            *c_dquot[MAXQUOTAS]; /* cnode's quota info */
  93         struct klist            c_knotes;       /* knotes attached to this vnode */
  94         u_long                  c_childhint;    /* catalog hint for children */
  95         struct cat_desc         c_desc;         /* cnode's descriptor */
  96         struct cat_attr         c_attr;         /* cnode's attributes */
  97         TAILQ_HEAD(hfs_hinthead, directoryhint) c_hintlist;  /* directory hint list */
  98         int16_t                 c_dirhinttag;   /* directory hint tag */
  99         union {
 100             int16_t     cu_dirhintcnt;          /* directory hint count */
 101             int16_t     cu_syslockcount;        /* system file use only */
 102         } c_union;
 103         struct filefork         *c_datafork;    /* cnode's data fork */
 104         struct filefork         *c_rsrcfork;    /* cnode's rsrc fork */
 105         atomicflag_t    c_touch_acctime;
 106         atomicflag_t    c_touch_chgtime;
 107         atomicflag_t    c_touch_modtime;
 108 };
 109 typedef struct cnode cnode_t;
 110
 111 /* Aliases for common cnode fields */
 112 #define c_cnid          c_desc.cd_cnid
 113 #define c_hint          c_desc.cd_hint
 114 #define c_parentcnid    c_desc.cd_parentcnid
 115 #define c_encoding      c_desc.cd_encoding
 116
 117 #define c_fileid        c_attr.ca_fileid
 118 #define c_mode          c_attr.ca_mode
 119 #define c_nlink         c_attr.ca_nlink
 120 #define c_uid           c_attr.ca_uid
 121 #define c_gid           c_attr.ca_gid
 122 #define c_rdev          c_attr.ca_rdev
 123 #define c_atime         c_attr.ca_atime
 124 #define c_mtime         c_attr.ca_mtime
 125 #define c_ctime         c_attr.ca_ctime
 126 #define c_itime         c_attr.ca_itime
 127 #define c_btime         c_attr.ca_btime
 128 #define c_flags         c_attr.ca_flags
 129 #define c_finderinfo    c_attr.ca_finderinfo
 130 #define c_blocks        c_attr.ca_blocks
 131 #define c_attrblks      c_attr.ca_attrblks
 132 #define c_entries       c_attr.ca_entries
 133 #define c_zftimeout     c_childhint
 134
 135 #define c_dirhintcnt    c_union.cu_dirhintcnt
 136 #define c_syslockcount  c_union.cu_syslockcount
 137
 138
 139 /* hash maintenance flags kept in c_hflag and protected by hfs_chash_mutex */
 140 #define H_ALLOC         0x00001 /* CNode is being allocated */
 141 #define H_ATTACH        0x00002 /* CNode is being attached to by another vnode */
 142 #define H_TRANSIT       0x00004 /* CNode is getting recycled  */
 143 #define H_WAITING       0x00008 /* CNode is being waited for */
 144
 145
 146 /* Runtime cnode flags (kept in c_flag) */
 147 #define C_NEED_RVNODE_PUT  0x00001  /* Need to do a vnode_put on c_rsrc_vp after the unlock */
 148 #define C_NEED_DVNODE_PUT  0x00002  /* Need to do a vnode_put on c_vp after the unlock */
 149 #define C_ZFWANTSYNC       0x00004  /* fsync requested and file has holes */
 150 #define C_FROMSYNC         0x00008  /* fsync was called from sync */
 151
 152 #define C_MODIFIED         0x00010  /* CNode has been modified */
 153 #define C_NOEXISTS         0x00020  /* CNode has been deleted, catalog entry is gone */
 154 #define C_DELETED          0x00040  /* CNode has been marked to be deleted */
 155 #define C_HARDLINK         0x00080  /* CNode is a hard link */
 156
 157 #define C_FORCEUPDATE      0x00100  /* force the catalog entry update */
 158 #define C_HASXATTRS        0x00200  /* cnode has extended attributes */
 159
 160
 161 #define ZFTIMELIMIT     (5 * 60)
 162
 163 /*
 164  * Convert between cnode pointers and vnode pointers
 165  */
 166 #define VTOC(vp)        ((struct cnode *)vnode_fsnode((vp)))
 167
 168 #define CTOV(cp,rsrc)   (((rsrc) && S_ISREG((cp)->c_mode)) ? \
 169                         (cp)->c_rsrc_vp : (cp)->c_vp)
 170
 171 /*
 172  * Convert between vnode pointers and file forks
 173  *
 174  * Note: no CTOF since that is ambiguous
 175  */
 176
 177 #define FTOC(fp)        ((fp)->ff_cp)
 178
 179 #define VTOF(vp)        ((vp) == VTOC((vp))->c_rsrc_vp ?        \
 180                          VTOC((vp))->c_rsrcfork :               \
 181                          VTOC((vp))->c_datafork)
 182
 183 #define FTOV(fp)        ((fp) == FTOC(fp)->c_rsrcfork ?         \
 184                          FTOC(fp)->c_rsrc_vp :                  \
 185                          FTOC(fp)->c_vp)
 186
 187
 188 /*
 189  * Test for a resource fork
 190  */
 191 #define FORK_IS_RSRC(fp)        ((fp) == FTOC(fp)->c_rsrcfork)
 192
 193 #define VNODE_IS_RSRC(vp)       ((vp) == VTOC((vp))->c_rsrc_vp)
 194
 195
 196 #define ATIME_ONDISK_ACCURACY   300
 197
 198
 199 /* This overlays the FileID portion of NFS file handles. */
 200 struct hfsfid {
 201         u_int32_t hfsfid_cnid;  /* Catalog node ID. */
 202         u_int32_t hfsfid_gen;   /* Generation number (create date). */
 203 };
 204
 205
 206 extern void hfs_touchtimes(struct hfsmount *, struct cnode *);
 207
 208 /*
 209  * HFS cnode hash functions.
 210  */
 211 extern void  hfs_chashinit(void);
 212 extern void  hfs_chashinsert(struct cnode *cp);
 213 extern int   hfs_chashremove(struct cnode *cp);
 214 extern void  hfs_chash_abort(struct cnode *cp);
 215 extern void  hfs_chash_rehash(struct cnode *cp1, struct cnode *cp2);
 216 extern void  hfs_chashwakeup(struct cnode *cp, int flags);
 217 extern void  hfs_chash_mark_in_transit(struct cnode *cp);
 218
 219 extern struct vnode * hfs_chash_getvnode(dev_t dev, ino_t inum, int wantrsrc, int skiplock);
 220 extern struct cnode * hfs_chash_getcnode(dev_t dev, ino_t inum, struct vnode **vpp, int wantrsrc, int skiplock);
 221 extern int hfs_chash_snoop(dev_t, ino_t, int (*)(const struct cat_desc *,
 222                             const struct cat_attr *, void *), void *);
 223
 224 /*
 225  * HFS directory hint functions.
 226  */
 227 extern directoryhint_t * hfs_getdirhint(struct cnode *, int);
 228 extern void  hfs_reldirhint(struct cnode *, directoryhint_t *);
 229 extern void  hfs_reldirhints(struct cnode *, int);
 230
 231 /*
 232  * HFS cnode lock functions.
 233  *
 234  *  HFS Locking Order:
 235  *
 236  *  1. cnode truncate lock (if needed)
 237  *  2. cnode lock (in parent-child order if related, otherwise by address order)
 238  *  3. journal (if needed)
 239  *  4. system files (as needed)
 240  *       A. Catalog B-tree file
 241  *       B. Attributes B-tree file
 242  *       C. Allocation Bitmap file (always exclusive, supports recursion)
 243  *       D. Overflow Extents B-tree file (always exclusive, supports recursion)
 244  *  5. hfs mount point (always last)
 245  *
 246  */
 247 enum hfslocktype  {HFS_SHARED_LOCK = 1, HFS_EXCLUSIVE_LOCK = 2, HFS_FORCE_LOCK = 3};
 248 #define HFS_SHARED_OWNER  (void *)0xffffffff
 249
 250 extern int hfs_lock(struct cnode *, enum hfslocktype);
 251 extern int hfs_lockpair(struct cnode *, struct cnode *, enum hfslocktype);
 252 extern int hfs_lockfour(struct cnode *, struct cnode *, struct cnode *, struct cnode *,
 253                         enum hfslocktype);
 254
 255 extern void hfs_unlock(struct cnode *);
 256 extern void hfs_unlockpair(struct cnode *, struct cnode *);
 257 extern void hfs_unlockfour(struct cnode *, struct cnode *, struct cnode *, struct cnode *);
 258
 259 extern void hfs_lock_truncate(struct cnode *, int);
 260 extern void hfs_unlock_truncate(struct cnode *);
 261
 262 #endif /* __APPLE_API_PRIVATE */
 263 #endif /* KERNEL */
 264
 265 #endif /* ! _HFS_CNODE_H_ */