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