fs/xfs/xfs_log_priv.h

   1 /*
   2  * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
   3  * All Rights Reserved.
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it would be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write the Free Software Foundation,
  16  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  17  */
  18 #ifndef __XFS_LOG_PRIV_H__
  19 #define __XFS_LOG_PRIV_H__
  20
  21 struct xfs_buf;
  22 struct ktrace;
  23 struct log;
  24 struct xlog_ticket;
  25 struct xfs_buf_cancel;
  26 struct xfs_mount;
  27
  28 /*
  29  * Macros, structures, prototypes for internal log manager use.
  30  */
  31
  32 #define XLOG_MIN_ICLOGS         2
  33 #define XLOG_MED_ICLOGS         4
  34 #define XLOG_MAX_ICLOGS         8
  35 #define XLOG_CALLBACK_SIZE      10
  36 #define XLOG_HEADER_MAGIC_NUM   0xFEEDbabe      /* Invalid cycle number */
  37 #define XLOG_VERSION_1          1
  38 #define XLOG_VERSION_2          2               /* Large IClogs, Log sunit */
  39 #define XLOG_VERSION_OKBITS     (XLOG_VERSION_1 | XLOG_VERSION_2)
  40 #define XLOG_RECORD_BSIZE       (16*1024)       /* eventually 32k */
  41 #define XLOG_BIG_RECORD_BSIZE   (32*1024)       /* 32k buffers */
  42 #define XLOG_MAX_RECORD_BSIZE   (256*1024)
  43 #define XLOG_HEADER_CYCLE_SIZE  (32*1024)       /* cycle data in header */
  44 #define XLOG_RECORD_BSHIFT      14              /* 16384 == 1 << 14 */
  45 #define XLOG_BIG_RECORD_BSHIFT  15              /* 32k == 1 << 15 */
  46 #define XLOG_MAX_RECORD_BSHIFT  18              /* 256k == 1 << 18 */
  47 #define XLOG_BTOLSUNIT(log, b)  (((b)+(log)->l_mp->m_sb.sb_logsunit-1) / \
  48                                  (log)->l_mp->m_sb.sb_logsunit)
  49 #define XLOG_LSUNITTOB(log, su) ((su) * (log)->l_mp->m_sb.sb_logsunit)
  50
  51 #define XLOG_HEADER_SIZE        512
  52
  53 #define XLOG_REC_SHIFT(log) \
  54         BTOBB(1 << (XFS_SB_VERSION_HASLOGV2(&log->l_mp->m_sb) ? \
  55          XLOG_MAX_RECORD_BSHIFT : XLOG_BIG_RECORD_BSHIFT))
  56 #define XLOG_TOTAL_REC_SHIFT(log) \
  57         BTOBB(XLOG_MAX_ICLOGS << (XFS_SB_VERSION_HASLOGV2(&log->l_mp->m_sb) ? \
  58          XLOG_MAX_RECORD_BSHIFT : XLOG_BIG_RECORD_BSHIFT))
  59
  60 /*
  61  *  set lsns
  62  */
  63
  64 #define ASSIGN_ANY_LSN_HOST(lsn,cycle,block)  \
  65     { \
  66         (lsn) = ((xfs_lsn_t)(cycle)<<32)|(block); \
  67     }
  68 #define ASSIGN_ANY_LSN_DISK(lsn,cycle,block)  \
  69     { \
  70         INT_SET(((uint *)&(lsn))[0], ARCH_CONVERT, (cycle)); \
  71         INT_SET(((uint *)&(lsn))[1], ARCH_CONVERT, (block)); \
  72     }
  73 #define ASSIGN_LSN(lsn,log) \
  74     ASSIGN_ANY_LSN_DISK(lsn,(log)->l_curr_cycle,(log)->l_curr_block);
  75
  76 #define XLOG_SET(f,b)           (((f) & (b)) == (b))
  77
  78 #define GET_CYCLE(ptr, arch) \
  79     (INT_GET(*(uint *)(ptr), arch) == XLOG_HEADER_MAGIC_NUM ? \
  80          INT_GET(*((uint *)(ptr)+1), arch) : \
  81          INT_GET(*(uint *)(ptr), arch) \
  82     )
  83
  84 #define BLK_AVG(blk1, blk2)     ((blk1+blk2) >> 1)
  85
  86
  87 #ifdef __KERNEL__
  88
  89 /*
  90  * get client id from packed copy.
  91  *
  92  * this hack is here because the xlog_pack code copies four bytes
  93  * of xlog_op_header containing the fields oh_clientid, oh_flags
  94  * and oh_res2 into the packed copy.
  95  *
  96  * later on this four byte chunk is treated as an int and the
  97  * client id is pulled out.
  98  *
  99  * this has endian issues, of course.
 100  */
 101
 102 #ifndef XFS_NATIVE_HOST
 103 #define GET_CLIENT_ID(i,arch) \
 104     ((i) & 0xff)
 105 #else
 106 #define GET_CLIENT_ID(i,arch) \
 107     ((i) >> 24)
 108 #endif
 109
 110 #define GRANT_LOCK(log)         mutex_spinlock(&(log)->l_grant_lock)
 111 #define GRANT_UNLOCK(log, s)    mutex_spinunlock(&(log)->l_grant_lock, s)
 112 #define LOG_LOCK(log)           mutex_spinlock(&(log)->l_icloglock)
 113 #define LOG_UNLOCK(log, s)      mutex_spinunlock(&(log)->l_icloglock, s)
 114
 115 #define xlog_panic(args...)     cmn_err(CE_PANIC, ## args)
 116 #define xlog_exit(args...)      cmn_err(CE_PANIC, ## args)
 117 #define xlog_warn(args...)      cmn_err(CE_WARN, ## args)
 118
 119 /*
 120  * In core log state
 121  */
 122 #define XLOG_STATE_ACTIVE    0x0001 /* Current IC log being written to */
 123 #define XLOG_STATE_WANT_SYNC 0x0002 /* Want to sync this iclog; no more writes */
 124 #define XLOG_STATE_SYNCING   0x0004 /* This IC log is syncing */
 125 #define XLOG_STATE_DONE_SYNC 0x0008 /* Done syncing to disk */
 126 #define XLOG_STATE_DO_CALLBACK \
 127                              0x0010 /* Process callback functions */
 128 #define XLOG_STATE_CALLBACK  0x0020 /* Callback functions now */
 129 #define XLOG_STATE_DIRTY     0x0040 /* Dirty IC log, not ready for ACTIVE status*/
 130 #define XLOG_STATE_IOERROR   0x0080 /* IO error happened in sync'ing log */
 131 #define XLOG_STATE_ALL       0x7FFF /* All possible valid flags */
 132 #define XLOG_STATE_NOTUSED   0x8000 /* This IC log not being used */
 133 #endif  /* __KERNEL__ */
 134
 135 /*
 136  * Flags to log operation header
 137  *
 138  * The first write of a new transaction will be preceded with a start
 139  * record, XLOG_START_TRANS.  Once a transaction is committed, a commit
 140  * record is written, XLOG_COMMIT_TRANS.  If a single region can not fit into
 141  * the remainder of the current active in-core log, it is split up into
 142  * multiple regions.  Each partial region will be marked with a
 143  * XLOG_CONTINUE_TRANS until the last one, which gets marked with XLOG_END_TRANS.
 144  *
 145  */
 146 #define XLOG_START_TRANS        0x01    /* Start a new transaction */
 147 #define XLOG_COMMIT_TRANS       0x02    /* Commit this transaction */
 148 #define XLOG_CONTINUE_TRANS     0x04    /* Cont this trans into new region */
 149 #define XLOG_WAS_CONT_TRANS     0x08    /* Cont this trans into new region */
 150 #define XLOG_END_TRANS          0x10    /* End a continued transaction */
 151 #define XLOG_UNMOUNT_TRANS      0x20    /* Unmount a filesystem transaction */
 152 #define XLOG_SKIP_TRANS         (XLOG_COMMIT_TRANS | XLOG_CONTINUE_TRANS | \
 153                                  XLOG_WAS_CONT_TRANS | XLOG_END_TRANS | \
 154                                  XLOG_UNMOUNT_TRANS)
 155
 156 #ifdef __KERNEL__
 157 /*
 158  * Flags to log ticket
 159  */
 160 #define XLOG_TIC_INITED         0x1     /* has been initialized */
 161 #define XLOG_TIC_PERM_RESERV    0x2     /* permanent reservation */
 162 #define XLOG_TIC_IN_Q           0x4
 163 #endif  /* __KERNEL__ */
 164
 165 #define XLOG_UNMOUNT_TYPE       0x556e  /* Un for Unmount */
 166
 167 /*
 168  * Flags for log structure
 169  */
 170 #define XLOG_CHKSUM_MISMATCH    0x1     /* used only during recovery */
 171 #define XLOG_ACTIVE_RECOVERY    0x2     /* in the middle of recovery */
 172 #define XLOG_RECOVERY_NEEDED    0x4     /* log was recovered */
 173 #define XLOG_IO_ERROR           0x8     /* log hit an I/O error, and being
 174                                            shutdown */
 175 typedef __uint32_t xlog_tid_t;
 176
 177
 178 #ifdef __KERNEL__
 179 /*
 180  * Below are states for covering allocation transactions.
 181  * By covering, we mean changing the h_tail_lsn in the last on-disk
 182  * log write such that no allocation transactions will be re-done during
 183  * recovery after a system crash. Recovery starts at the last on-disk
 184  * log write.
 185  *
 186  * These states are used to insert dummy log entries to cover
 187  * space allocation transactions which can undo non-transactional changes
 188  * after a crash. Writes to a file with space
 189  * already allocated do not result in any transactions. Allocations
 190  * might include space beyond the EOF. So if we just push the EOF a
 191  * little, the last transaction for the file could contain the wrong
 192  * size. If there is no file system activity, after an allocation
 193  * transaction, and the system crashes, the allocation transaction
 194  * will get replayed and the file will be truncated. This could
 195  * be hours/days/... after the allocation occurred.
 196  *
 197  * The fix for this is to do two dummy transactions when the
 198  * system is idle. We need two dummy transaction because the h_tail_lsn
 199  * in the log record header needs to point beyond the last possible
 200  * non-dummy transaction. The first dummy changes the h_tail_lsn to
 201  * the first transaction before the dummy. The second dummy causes
 202  * h_tail_lsn to point to the first dummy. Recovery starts at h_tail_lsn.
 203  *
 204  * These dummy transactions get committed when everything
 205  * is idle (after there has been some activity).
 206  *
 207  * There are 5 states used to control this.
 208  *
 209  *  IDLE -- no logging has been done on the file system or
 210  *              we are done covering previous transactions.
 211  *  NEED -- logging has occurred and we need a dummy transaction
 212  *              when the log becomes idle.
 213  *  DONE -- we were in the NEED state and have committed a dummy
 214  *              transaction.
 215  *  NEED2 -- we detected that a dummy transaction has gone to the
 216  *              on disk log with no other transactions.
 217  *  DONE2 -- we committed a dummy transaction when in the NEED2 state.
 218  *
 219  * There are two places where we switch states:
 220  *
 221  * 1.) In xfs_sync, when we detect an idle log and are in NEED or NEED2.
 222  *      We commit the dummy transaction and switch to DONE or DONE2,
 223  *      respectively. In all other states, we don't do anything.
 224  *
 225  * 2.) When we finish writing the on-disk log (xlog_state_clean_log).
 226  *
 227  *      No matter what state we are in, if this isn't the dummy
 228  *      transaction going out, the next state is NEED.
 229  *      So, if we aren't in the DONE or DONE2 states, the next state
 230  *      is NEED. We can't be finishing a write of the dummy record
 231  *      unless it was committed and the state switched to DONE or DONE2.
 232  *
 233  *      If we are in the DONE state and this was a write of the
 234  *              dummy transaction, we move to NEED2.
 235  *
 236  *      If we are in the DONE2 state and this was a write of the
 237  *              dummy transaction, we move to IDLE.
 238  *
 239  *
 240  * Writing only one dummy transaction can get appended to
 241  * one file space allocation. When this happens, the log recovery
 242  * code replays the space allocation and a file could be truncated.
 243  * This is why we have the NEED2 and DONE2 states before going idle.
 244  */
 245
 246 #define XLOG_STATE_COVER_IDLE   0
 247 #define XLOG_STATE_COVER_NEED   1
 248 #define XLOG_STATE_COVER_DONE   2
 249 #define XLOG_STATE_COVER_NEED2  3
 250 #define XLOG_STATE_COVER_DONE2  4
 251
 252 #define XLOG_COVER_OPS          5
 253
 254
 255 /* Ticket reservation region accounting */
 256 #define XLOG_TIC_LEN_MAX        15
 257 #define XLOG_TIC_RESET_RES(t) ((t)->t_res_num = \
 258                                 (t)->t_res_arr_sum = (t)->t_res_num_ophdrs = 0)
 259 #define XLOG_TIC_ADD_OPHDR(t) ((t)->t_res_num_ophdrs++)
 260 #define XLOG_TIC_ADD_REGION(t, len, type)                               \
 261         do {                                                            \
 262                 if ((t)->t_res_num == XLOG_TIC_LEN_MAX) {               \
 263                         /* add to overflow and start again */           \
 264                         (t)->t_res_o_flow += (t)->t_res_arr_sum;        \
 265                         (t)->t_res_num = 0;                             \
 266                         (t)->t_res_arr_sum = 0;                         \
 267                 }                                                       \
 268                 (t)->t_res_arr[(t)->t_res_num].r_len = (len);           \
 269                 (t)->t_res_arr[(t)->t_res_num].r_type = (type);         \
 270                 (t)->t_res_arr_sum += (len);                            \
 271                 (t)->t_res_num++;                                       \
 272         } while (0)
 273
 274 /*
 275  * Reservation region
 276  * As would be stored in xfs_log_iovec but without the i_addr which
 277  * we don't care about.
 278  */
 279 typedef struct xlog_res {
 280         uint    r_len;  /* region length                :4 */
 281         uint    r_type; /* region's transaction type    :4 */
 282 } xlog_res_t;
 283
 284 typedef struct xlog_ticket {
 285         sv_t               t_sema;       /* sleep on this semaphore      : 20 */
 286         struct xlog_ticket *t_next;      /*                              :4|8 */
 287         struct xlog_ticket *t_prev;      /*                              :4|8 */
 288         xlog_tid_t         t_tid;        /* transaction identifier       : 4  */
 289         int                t_curr_res;   /* current reservation in bytes : 4  */
 290         int                t_unit_res;   /* unit reservation in bytes    : 4  */
 291         char               t_ocnt;       /* original count               : 1  */
 292         char               t_cnt;        /* current count                : 1  */
 293         char               t_clientid;   /* who does this belong to;     : 1  */
 294         char               t_flags;      /* properties of reservation    : 1  */
 295         uint               t_trans_type; /* transaction type             : 4  */
 296
 297         /* reservation array fields */
 298         uint               t_res_num;                    /* num in array : 4 */
 299         uint               t_res_num_ophdrs;             /* num op hdrs  : 4 */
 300         uint               t_res_arr_sum;                /* array sum    : 4 */
 301         uint               t_res_o_flow;                 /* sum overflow : 4 */
 302         xlog_res_t         t_res_arr[XLOG_TIC_LEN_MAX];  /* array of res : 8 * 15 */
 303 } xlog_ticket_t;
 304
 305 #endif
 306
 307
 308 typedef struct xlog_op_header {
 309         xlog_tid_t oh_tid;      /* transaction id of operation  :  4 b */
 310         int        oh_len;      /* bytes in data region         :  4 b */
 311         __uint8_t  oh_clientid; /* who sent me this             :  1 b */
 312         __uint8_t  oh_flags;    /*                              :  1 b */
 313         ushort     oh_res2;     /* 32 bit align                 :  2 b */
 314 } xlog_op_header_t;
 315
 316
 317 /* valid values for h_fmt */
 318 #define XLOG_FMT_UNKNOWN  0
 319 #define XLOG_FMT_LINUX_LE 1
 320 #define XLOG_FMT_LINUX_BE 2
 321 #define XLOG_FMT_IRIX_BE  3
 322
 323 /* our fmt */
 324 #ifdef XFS_NATIVE_HOST
 325 #define XLOG_FMT XLOG_FMT_LINUX_BE
 326 #else
 327 #define XLOG_FMT XLOG_FMT_LINUX_LE
 328 #endif
 329
 330 typedef struct xlog_rec_header {
 331         uint      h_magicno;    /* log record (LR) identifier           :  4 */
 332         uint      h_cycle;      /* write cycle of log                   :  4 */
 333         int       h_version;    /* LR version                           :  4 */
 334         int       h_len;        /* len in bytes; should be 64-bit aligned: 4 */
 335         xfs_lsn_t h_lsn;        /* lsn of this LR                       :  8 */
 336         xfs_lsn_t h_tail_lsn;   /* lsn of 1st LR w/ buffers not committed: 8 */
 337         uint      h_chksum;     /* may not be used; non-zero if used    :  4 */
 338         int       h_prev_block; /* block number to previous LR          :  4 */
 339         int       h_num_logops; /* number of log operations in this LR  :  4 */
 340         uint      h_cycle_data[XLOG_HEADER_CYCLE_SIZE / BBSIZE];
 341         /* new fields */
 342         int       h_fmt;        /* format of log record                 :  4 */
 343         uuid_t    h_fs_uuid;    /* uuid of FS                           : 16 */
 344         int       h_size;       /* iclog size                           :  4 */
 345 } xlog_rec_header_t;
 346
 347 typedef struct xlog_rec_ext_header {
 348         uint      xh_cycle;     /* write cycle of log                   : 4 */
 349         uint      xh_cycle_data[XLOG_HEADER_CYCLE_SIZE / BBSIZE]; /*    : 256 */
 350 } xlog_rec_ext_header_t;
 351
 352 #ifdef __KERNEL__
 353 /*
 354  * - A log record header is 512 bytes.  There is plenty of room to grow the
 355  *      xlog_rec_header_t into the reserved space.
 356  * - ic_data follows, so a write to disk can start at the beginning of
 357  *      the iclog.
 358  * - ic_forcesema is used to implement synchronous forcing of the iclog to disk.
 359  * - ic_next is the pointer to the next iclog in the ring.
 360  * - ic_bp is a pointer to the buffer used to write this incore log to disk.
 361  * - ic_log is a pointer back to the global log structure.
 362  * - ic_callback is a linked list of callback function/argument pairs to be
 363  *      called after an iclog finishes writing.
 364  * - ic_size is the full size of the header plus data.
 365  * - ic_offset is the current number of bytes written to in this iclog.
 366  * - ic_refcnt is bumped when someone is writing to the log.
 367  * - ic_state is the state of the iclog.
 368  */
 369 typedef struct xlog_iclog_fields {
 370         sv_t                    ic_forcesema;
 371         sv_t                    ic_writesema;
 372         struct xlog_in_core     *ic_next;
 373         struct xlog_in_core     *ic_prev;
 374         struct xfs_buf          *ic_bp;
 375         struct log              *ic_log;
 376         xfs_log_callback_t      *ic_callback;
 377         xfs_log_callback_t      **ic_callback_tail;
 378 #ifdef XFS_LOG_TRACE
 379         struct ktrace           *ic_trace;
 380 #endif
 381         int                     ic_size;
 382         int                     ic_offset;
 383         int                     ic_refcnt;
 384         int                     ic_bwritecnt;
 385         ushort_t                ic_state;
 386         char                    *ic_datap;      /* pointer to iclog data */
 387 } xlog_iclog_fields_t;
 388
 389 typedef union xlog_in_core2 {
 390         xlog_rec_header_t       hic_header;
 391         xlog_rec_ext_header_t   hic_xheader;
 392         char                    hic_sector[XLOG_HEADER_SIZE];
 393 } xlog_in_core_2_t;
 394
 395 typedef struct xlog_in_core {
 396         xlog_iclog_fields_t     hic_fields;
 397         xlog_in_core_2_t        *hic_data;
 398 } xlog_in_core_t;
 399
 400 /*
 401  * Defines to save our code from this glop.
 402  */
 403 #define ic_forcesema    hic_fields.ic_forcesema
 404 #define ic_writesema    hic_fields.ic_writesema
 405 #define ic_next         hic_fields.ic_next
 406 #define ic_prev         hic_fields.ic_prev
 407 #define ic_bp           hic_fields.ic_bp
 408 #define ic_log          hic_fields.ic_log
 409 #define ic_callback     hic_fields.ic_callback
 410 #define ic_callback_tail hic_fields.ic_callback_tail
 411 #define ic_trace        hic_fields.ic_trace
 412 #define ic_size         hic_fields.ic_size
 413 #define ic_offset       hic_fields.ic_offset
 414 #define ic_refcnt       hic_fields.ic_refcnt
 415 #define ic_bwritecnt    hic_fields.ic_bwritecnt
 416 #define ic_state        hic_fields.ic_state
 417 #define ic_datap        hic_fields.ic_datap
 418 #define ic_header       hic_data->hic_header
 419
 420 /*
 421  * The reservation head lsn is not made up of a cycle number and block number.
 422  * Instead, it uses a cycle number and byte number.  Logs don't expect to
 423  * overflow 31 bits worth of byte offset, so using a byte number will mean
 424  * that round off problems won't occur when releasing partial reservations.
 425  */
 426 typedef struct log {
 427         /* The following block of fields are changed while holding icloglock */
 428         sema_t                  l_flushsema;    /* iclog flushing semaphore */
 429         int                     l_flushcnt;     /* # of procs waiting on this
 430                                                  * sema */
 431         int                     l_ticket_cnt;   /* free ticket count */
 432         int                     l_ticket_tcnt;  /* total ticket count */
 433         int                     l_covered_state;/* state of "covering disk
 434                                                  * log entries" */
 435         xlog_ticket_t           *l_freelist;    /* free list of tickets */
 436         xlog_ticket_t           *l_unmount_free;/* kmem_free these addresses */
 437         xlog_ticket_t           *l_tail;        /* free list of tickets */
 438         xlog_in_core_t          *l_iclog;       /* head log queue       */
 439         lock_t                  l_icloglock;    /* grab to change iclog state */
 440         xfs_lsn_t               l_tail_lsn;     /* lsn of 1st LR with unflushed
 441                                                  * buffers */
 442         xfs_lsn_t               l_last_sync_lsn;/* lsn of last LR on disk */
 443         struct xfs_mount        *l_mp;          /* mount point */
 444         struct xfs_buf          *l_xbuf;        /* extra buffer for log
 445                                                  * wrapping */
 446         struct xfs_buftarg      *l_targ;        /* buftarg of log */
 447         xfs_daddr_t             l_logBBstart;   /* start block of log */
 448         int                     l_logsize;      /* size of log in bytes */
 449         int                     l_logBBsize;    /* size of log in BB chunks */
 450         int                     l_curr_cycle;   /* Cycle number of log writes */
 451         int                     l_prev_cycle;   /* Cycle number before last
 452                                                  * block increment */
 453         int                     l_curr_block;   /* current logical log block */
 454         int                     l_prev_block;   /* previous logical log block */
 455         int                     l_iclog_size;   /* size of log in bytes */
 456         int                     l_iclog_size_log; /* log power size of log */
 457         int                     l_iclog_bufs;   /* number of iclog buffers */
 458
 459         /* The following field are used for debugging; need to hold icloglock */
 460         char                    *l_iclog_bak[XLOG_MAX_ICLOGS];
 461
 462         /* The following block of fields are changed while holding grant_lock */
 463         lock_t                  l_grant_lock;
 464         xlog_ticket_t           *l_reserve_headq;
 465         xlog_ticket_t           *l_write_headq;
 466         int                     l_grant_reserve_cycle;
 467         int                     l_grant_reserve_bytes;
 468         int                     l_grant_write_cycle;
 469         int                     l_grant_write_bytes;
 470
 471         /* The following fields don't need locking */
 472 #ifdef XFS_LOG_TRACE
 473         struct ktrace           *l_trace;
 474         struct ktrace           *l_grant_trace;
 475 #endif
 476         uint                    l_flags;
 477         uint                    l_quotaoffs_flag; /* XFS_DQ_*, for QUOTAOFFs */
 478         struct xfs_buf_cancel   **l_buf_cancel_table;
 479         int                     l_iclog_hsize;  /* size of iclog header */
 480         int                     l_iclog_heads;  /* # of iclog header sectors */
 481         uint                    l_sectbb_log;   /* log2 of sector size in BBs */
 482         uint                    l_sectbb_mask;  /* sector size (in BBs)
 483                                                  * alignment mask */
 484 } xlog_t;
 485
 486 #define XLOG_FORCED_SHUTDOWN(log)       ((log)->l_flags & XLOG_IO_ERROR)
 487
 488
 489 /* common routines */
 490 extern xfs_lsn_t xlog_assign_tail_lsn(struct xfs_mount *mp);
 491 extern int       xlog_find_tail(xlog_t  *log,
 492                                 xfs_daddr_t *head_blk,
 493                                 xfs_daddr_t *tail_blk);
 494 extern int       xlog_recover(xlog_t *log);
 495 extern int       xlog_recover_finish(xlog_t *log, int mfsi_flags);
 496 extern void      xlog_pack_data(xlog_t *log, xlog_in_core_t *iclog, int);
 497 extern void      xlog_recover_process_iunlinks(xlog_t *log);
 498
 499 extern struct xfs_buf *xlog_get_bp(xlog_t *, int);
 500 extern void      xlog_put_bp(struct xfs_buf *);
 501 extern int       xlog_bread(xlog_t *, xfs_daddr_t, int, struct xfs_buf *);
 502
 503 /* iclog tracing */
 504 #define XLOG_TRACE_GRAB_FLUSH  1
 505 #define XLOG_TRACE_REL_FLUSH   2
 506 #define XLOG_TRACE_SLEEP_FLUSH 3
 507 #define XLOG_TRACE_WAKE_FLUSH  4
 508
 509 #endif  /* __KERNEL__ */
 510
 511 #endif  /* __XFS_LOG_PRIV_H__ */