module/zfs/include/sys/zfs_znode.h

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
  23  * Use is subject to license terms.
  24  */
  25
  26 #ifndef _SYS_FS_ZFS_ZNODE_H
  27 #define _SYS_FS_ZFS_ZNODE_H
  28
  29 #ifdef _KERNEL
  30 #include <sys/isa_defs.h>
  31 #include <sys/types32.h>
  32 #include <sys/attr.h>
  33 #include <sys/list.h>
  34 #include <sys/dmu.h>
  35 #include <sys/zfs_vfsops.h>
  36 #include <sys/rrwlock.h>
  37 #endif
  38 #include <sys/zfs_acl.h>
  39 #include <sys/zil.h>
  40
  41 #ifdef  __cplusplus
  42 extern "C" {
  43 #endif
  44
  45 /*
  46  * Additional file level attributes, that are stored
  47  * in the upper half of zp_flags
  48  */
  49 #define ZFS_READONLY            0x0000000100000000
  50 #define ZFS_HIDDEN              0x0000000200000000
  51 #define ZFS_SYSTEM              0x0000000400000000
  52 #define ZFS_ARCHIVE             0x0000000800000000
  53 #define ZFS_IMMUTABLE           0x0000001000000000
  54 #define ZFS_NOUNLINK            0x0000002000000000
  55 #define ZFS_APPENDONLY          0x0000004000000000
  56 #define ZFS_NODUMP              0x0000008000000000
  57 #define ZFS_OPAQUE              0x0000010000000000
  58 #define ZFS_AV_QUARANTINED      0x0000020000000000
  59 #define ZFS_AV_MODIFIED         0x0000040000000000
  60
  61 #define ZFS_ATTR_SET(zp, attr, value)   \
  62 { \
  63         if (value) \
  64                 zp->z_phys->zp_flags |= attr; \
  65         else \
  66                 zp->z_phys->zp_flags &= ~attr; \
  67 }
  68
  69 /*
  70  * Define special zfs pflags
  71  */
  72 #define ZFS_XATTR               0x1             /* is an extended attribute */
  73 #define ZFS_INHERIT_ACE         0x2             /* ace has inheritable ACEs */
  74 #define ZFS_ACL_TRIVIAL         0x4             /* files ACL is trivial */
  75 #define ZFS_ACL_OBJ_ACE         0x8             /* ACL has CMPLX Object ACE */
  76 #define ZFS_ACL_PROTECTED       0x10            /* ACL protected */
  77 #define ZFS_ACL_DEFAULTED       0x20            /* ACL should be defaulted */
  78 #define ZFS_ACL_AUTO_INHERIT    0x40            /* ACL should be inherited */
  79 #define ZFS_BONUS_SCANSTAMP     0x80            /* Scanstamp in bonus area */
  80
  81 /*
  82  * Is ID ephemeral?
  83  */
  84 #define IS_EPHEMERAL(x)         (x > MAXUID)
  85
  86 /*
  87  * Should we use FUIDs?
  88  */
  89 #define USE_FUIDS(version, os)  (version >= ZPL_VERSION_FUID &&\
  90     spa_version(dmu_objset_spa(os)) >= SPA_VERSION_FUID)
  91
  92 #define MASTER_NODE_OBJ 1
  93
  94 /*
  95  * Special attributes for master node.
  96  */
  97 #define ZFS_FSID                "FSID"
  98 #define ZFS_UNLINKED_SET        "DELETE_QUEUE"
  99 #define ZFS_ROOT_OBJ            "ROOT"
 100 #define ZPL_VERSION_STR         "VERSION"
 101 #define ZFS_FUID_TABLES         "FUID"
 102
 103 #define ZFS_MAX_BLOCKSIZE       (SPA_MAXBLOCKSIZE)
 104
 105 /* Path component length */
 106 /*
 107  * The generic fs code uses MAXNAMELEN to represent
 108  * what the largest component length is.  Unfortunately,
 109  * this length includes the terminating NULL.  ZFS needs
 110  * to tell the users via pathconf() and statvfs() what the
 111  * true maximum length of a component is, excluding the NULL.
 112  */
 113 #define ZFS_MAXNAMELEN  (MAXNAMELEN - 1)
 114
 115 /*
 116  * Convert mode bits (zp_mode) to BSD-style DT_* values for storing in
 117  * the directory entries.
 118  */
 119 #define IFTODT(mode) (((mode) & S_IFMT) >> 12)
 120
 121 /*
 122  * The directory entry has the type (currently unused on Solaris) in the
 123  * top 4 bits, and the object number in the low 48 bits.  The "middle"
 124  * 12 bits are unused.
 125  */
 126 #define ZFS_DIRENT_TYPE(de) BF64_GET(de, 60, 4)
 127 #define ZFS_DIRENT_OBJ(de) BF64_GET(de, 0, 48)
 128
 129 /*
 130  * This is the persistent portion of the znode.  It is stored
 131  * in the "bonus buffer" of the file.  Short symbolic links
 132  * are also stored in the bonus buffer.
 133  */
 134 typedef struct znode_phys {
 135         uint64_t zp_atime[2];           /*  0 - last file access time */
 136         uint64_t zp_mtime[2];           /* 16 - last file modification time */
 137         uint64_t zp_ctime[2];           /* 32 - last file change time */
 138         uint64_t zp_crtime[2];          /* 48 - creation time */
 139         uint64_t zp_gen;                /* 64 - generation (txg of creation) */
 140         uint64_t zp_mode;               /* 72 - file mode bits */
 141         uint64_t zp_size;               /* 80 - size of file */
 142         uint64_t zp_parent;             /* 88 - directory parent (`..') */
 143         uint64_t zp_links;              /* 96 - number of links to file */
 144         uint64_t zp_xattr;              /* 104 - DMU object for xattrs */
 145         uint64_t zp_rdev;               /* 112 - dev_t for VBLK & VCHR files */
 146         uint64_t zp_flags;              /* 120 - persistent flags */
 147         uint64_t zp_uid;                /* 128 - file owner */
 148         uint64_t zp_gid;                /* 136 - owning group */
 149         uint64_t zp_zap;                /* 144 - extra attributes */
 150         uint64_t zp_pad[3];             /* 152 - future */
 151         zfs_acl_phys_t zp_acl;          /* 176 - 263 ACL */
 152         /*
 153          * Data may pad out any remaining bytes in the znode buffer, eg:
 154          *
 155          * |<---------------------- dnode_phys (512) ------------------------>|
 156          * |<-- dnode (192) --->|<----------- "bonus" buffer (320) ---------->|
 157          *                      |<---- znode (264) ---->|<---- data (56) ---->|
 158          *
 159          * At present, we use this space for the following:
 160          *  - symbolic links
 161          *  - 32-byte anti-virus scanstamp (regular files only)
 162          */
 163 } znode_phys_t;
 164
 165 /*
 166  * Directory entry locks control access to directory entries.
 167  * They are used to protect creates, deletes, and renames.
 168  * Each directory znode has a mutex and a list of locked names.
 169  */
 170 #ifdef _KERNEL
 171 typedef struct zfs_dirlock {
 172         char            *dl_name;       /* directory entry being locked */
 173         uint32_t        dl_sharecnt;    /* 0 if exclusive, > 0 if shared */
 174         uint16_t        dl_namesize;    /* set if dl_name was allocated */
 175         kcondvar_t      dl_cv;          /* wait for entry to be unlocked */
 176         struct znode    *dl_dzp;        /* directory znode */
 177         struct zfs_dirlock *dl_next;    /* next in z_dirlocks list */
 178 } zfs_dirlock_t;
 179
 180 typedef struct znode {
 181         struct zfsvfs   *z_zfsvfs;
 182         vnode_t         *z_vnode;
 183         uint64_t        z_id;           /* object ID for this znode */
 184         kmutex_t        z_lock;         /* znode modification lock */
 185         krwlock_t       z_parent_lock;  /* parent lock for directories */
 186         krwlock_t       z_name_lock;    /* "master" lock for dirent locks */
 187         zfs_dirlock_t   *z_dirlocks;    /* directory entry lock list */
 188         kmutex_t        z_range_lock;   /* protects changes to z_range_avl */
 189         avl_tree_t      z_range_avl;    /* avl tree of file range locks */
 190         uint8_t         z_unlinked;     /* file has been unlinked */
 191         uint8_t         z_atime_dirty;  /* atime needs to be synced */
 192         uint8_t         z_zn_prefetch;  /* Prefetch znodes? */
 193         uint_t          z_blksz;        /* block size in bytes */
 194         uint_t          z_seq;          /* modification sequence number */
 195         uint64_t        z_mapcnt;       /* number of pages mapped to file */
 196         uint64_t        z_last_itx;     /* last ZIL itx on this znode */
 197         uint64_t        z_gen;          /* generation (same as zp_gen) */
 198         uint32_t        z_sync_cnt;     /* synchronous open count */
 199         kmutex_t        z_acl_lock;     /* acl data lock */
 200         list_node_t     z_link_node;    /* all znodes in fs link */
 201         /*
 202          * These are dmu managed fields.
 203          */
 204         znode_phys_t    *z_phys;        /* pointer to persistent znode */
 205         dmu_buf_t       *z_dbuf;        /* buffer containing the z_phys */
 206 } znode_t;
 207
 208
 209 /*
 210  * Range locking rules
 211  * --------------------
 212  * 1. When truncating a file (zfs_create, zfs_setattr, zfs_space) the whole
 213  *    file range needs to be locked as RL_WRITER. Only then can the pages be
 214  *    freed etc and zp_size reset. zp_size must be set within range lock.
 215  * 2. For writes and punching holes (zfs_write & zfs_space) just the range
 216  *    being written or freed needs to be locked as RL_WRITER.
 217  *    Multiple writes at the end of the file must coordinate zp_size updates
 218  *    to ensure data isn't lost. A compare and swap loop is currently used
 219  *    to ensure the file size is at least the offset last written.
 220  * 3. For reads (zfs_read, zfs_get_data & zfs_putapage) just the range being
 221  *    read needs to be locked as RL_READER. A check against zp_size can then
 222  *    be made for reading beyond end of file.
 223  */
 224
 225 /*
 226  * Convert between znode pointers and vnode pointers
 227  */
 228 #define ZTOV(ZP)        ((ZP)->z_vnode)
 229 #define VTOZ(VP)        ((znode_t *)(VP)->v_data)
 230
 231 /*
 232  * ZFS_ENTER() is called on entry to each ZFS vnode and vfs operation.
 233  * ZFS_EXIT() must be called before exitting the vop.
 234  * ZFS_VERIFY_ZP() verifies the znode is valid.
 235  */
 236 #define ZFS_ENTER(zfsvfs) \
 237         { \
 238                 rrw_enter(&(zfsvfs)->z_teardown_lock, RW_READER, FTAG); \
 239                 if ((zfsvfs)->z_unmounted) { \
 240                         ZFS_EXIT(zfsvfs); \
 241                         return (EIO); \
 242                 } \
 243         }
 244
 245 #define ZFS_EXIT(zfsvfs) rrw_exit(&(zfsvfs)->z_teardown_lock, FTAG)
 246
 247 #define ZFS_VERIFY_ZP(zp) \
 248         if ((zp)->z_dbuf == NULL) { \
 249                 ZFS_EXIT((zp)->z_zfsvfs); \
 250                 return (EIO); \
 251         } \
 252
 253 /*
 254  * Macros for dealing with dmu_buf_hold
 255  */
 256 #define ZFS_OBJ_HASH(obj_num)   ((obj_num) & (ZFS_OBJ_MTX_SZ - 1))
 257 #define ZFS_OBJ_MUTEX(zfsvfs, obj_num)  \
 258         (&(zfsvfs)->z_hold_mtx[ZFS_OBJ_HASH(obj_num)])
 259 #define ZFS_OBJ_HOLD_ENTER(zfsvfs, obj_num) \
 260         mutex_enter(ZFS_OBJ_MUTEX((zfsvfs), (obj_num)))
 261 #define ZFS_OBJ_HOLD_TRYENTER(zfsvfs, obj_num) \
 262         mutex_tryenter(ZFS_OBJ_MUTEX((zfsvfs), (obj_num)))
 263 #define ZFS_OBJ_HOLD_EXIT(zfsvfs, obj_num) \
 264         mutex_exit(ZFS_OBJ_MUTEX((zfsvfs), (obj_num)))
 265
 266 /*
 267  * Macros to encode/decode ZFS stored time values from/to struct timespec
 268  */
 269 #define ZFS_TIME_ENCODE(tp, stmp)               \
 270 {                                               \
 271         (stmp)[0] = (uint64_t)(tp)->tv_sec;     \
 272         (stmp)[1] = (uint64_t)(tp)->tv_nsec;    \
 273 }
 274
 275 #define ZFS_TIME_DECODE(tp, stmp)               \
 276 {                                               \
 277         (tp)->tv_sec = (time_t)(stmp)[0];               \
 278         (tp)->tv_nsec = (long)(stmp)[1];                \
 279 }
 280
 281 /*
 282  * Timestamp defines
 283  */
 284 #define ACCESSED                (AT_ATIME)
 285 #define STATE_CHANGED           (AT_CTIME)
 286 #define CONTENT_MODIFIED        (AT_MTIME | AT_CTIME)
 287
 288 #define ZFS_ACCESSTIME_STAMP(zfsvfs, zp) \
 289         if ((zfsvfs)->z_atime && !((zfsvfs)->z_vfs->vfs_flag & VFS_RDONLY)) \
 290                 zfs_time_stamper(zp, ACCESSED, NULL)
 291
 292 extern int      zfs_init_fs(zfsvfs_t *, znode_t **);
 293 extern void     zfs_set_dataprop(objset_t *);
 294 extern void     zfs_create_fs(objset_t *os, cred_t *cr, nvlist_t *,
 295     dmu_tx_t *tx);
 296 extern void     zfs_time_stamper(znode_t *, uint_t, dmu_tx_t *);
 297 extern void     zfs_time_stamper_locked(znode_t *, uint_t, dmu_tx_t *);
 298 extern void     zfs_grow_blocksize(znode_t *, uint64_t, dmu_tx_t *);
 299 extern int      zfs_freesp(znode_t *, uint64_t, uint64_t, int, boolean_t);
 300 extern void     zfs_znode_init(void);
 301 extern void     zfs_znode_fini(void);
 302 extern int      zfs_zget(zfsvfs_t *, uint64_t, znode_t **);
 303 extern int      zfs_rezget(znode_t *);
 304 extern void     zfs_zinactive(znode_t *);
 305 extern void     zfs_znode_delete(znode_t *, dmu_tx_t *);
 306 extern void     zfs_znode_free(znode_t *);
 307 extern void     zfs_remove_op_tables();
 308 extern int      zfs_create_op_tables();
 309 extern int      zfs_sync(vfs_t *vfsp, short flag, cred_t *cr);
 310 extern dev_t    zfs_cmpldev(uint64_t);
 311 extern int      zfs_get_zplprop(objset_t *os, zfs_prop_t prop, uint64_t *value);
 312 extern int      zfs_set_version(const char *name, uint64_t newvers);
 313 extern int      zfs_get_stats(objset_t *os, nvlist_t *nv);
 314 extern void     zfs_znode_dmu_fini(znode_t *);
 315
 316 extern void zfs_log_create(zilog_t *zilog, dmu_tx_t *tx, uint64_t txtype,
 317     znode_t *dzp, znode_t *zp, char *name, vsecattr_t *, zfs_fuid_info_t *,
 318     vattr_t *vap);
 319 extern int zfs_log_create_txtype(zil_create_t, vsecattr_t *vsecp,
 320     vattr_t *vap);
 321 extern void zfs_log_remove(zilog_t *zilog, dmu_tx_t *tx, uint64_t txtype,
 322     znode_t *dzp, char *name);
 323 extern void zfs_log_link(zilog_t *zilog, dmu_tx_t *tx, uint64_t txtype,
 324     znode_t *dzp, znode_t *zp, char *name);
 325 extern void zfs_log_symlink(zilog_t *zilog, dmu_tx_t *tx, uint64_t txtype,
 326     znode_t *dzp, znode_t *zp, char *name, char *link);
 327 extern void zfs_log_rename(zilog_t *zilog, dmu_tx_t *tx, uint64_t txtype,
 328     znode_t *sdzp, char *sname, znode_t *tdzp, char *dname, znode_t *szp);
 329 extern void zfs_log_write(zilog_t *zilog, dmu_tx_t *tx, int txtype,
 330     znode_t *zp, offset_t off, ssize_t len, int ioflag);
 331 extern void zfs_log_truncate(zilog_t *zilog, dmu_tx_t *tx, int txtype,
 332     znode_t *zp, uint64_t off, uint64_t len);
 333 extern void zfs_log_setattr(zilog_t *zilog, dmu_tx_t *tx, int txtype,
 334     znode_t *zp, vattr_t *vap, uint_t mask_applied, zfs_fuid_info_t *fuidp);
 335 extern void zfs_log_acl(zilog_t *zilog, dmu_tx_t *tx, znode_t *zp,
 336     vsecattr_t *vsecp, zfs_fuid_info_t *fuidp);
 337 extern void zfs_xvattr_set(znode_t *zp, xvattr_t *xvap);
 338 extern void zfs_upgrade(zfsvfs_t *zfsvfs, dmu_tx_t *tx);
 339
 340 extern caddr_t zfs_map_page(page_t *, enum seg_rw);
 341 extern void zfs_unmap_page(page_t *, caddr_t);
 342
 343 extern zil_get_data_t zfs_get_data;
 344 extern zil_replay_func_t *zfs_replay_vector[TX_MAX_TYPE];
 345 extern int zfsfstype;
 346
 347 #endif /* _KERNEL */
 348
 349 extern int zfs_obj_to_path(objset_t *osp, uint64_t obj, char *buf, int len);
 350
 351 #ifdef  __cplusplus
 352 }
 353 #endif
 354
 355 #endif  /* _SYS_FS_ZFS_ZNODE_H */