aboutsummaryrefslogtreecommitdiff
path: root/sys/gnu/fs/xfs/xfs_log_priv.h
blob: 34bcbf50789c1e614e474427341cdcd6889e7efa (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
/*
 * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
 * All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it would be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write the Free Software Foundation,
 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
#ifndef	__XFS_LOG_PRIV_H__
#define __XFS_LOG_PRIV_H__

struct xfs_buf;
struct ktrace;
struct log;
struct xlog_ticket;
struct xfs_buf_cancel;
struct xfs_mount;

/*
 * Macros, structures, prototypes for internal log manager use.
 */

#define XLOG_MIN_ICLOGS		2
#define XLOG_MED_ICLOGS		4
#define XLOG_MAX_ICLOGS		8
#define XLOG_CALLBACK_SIZE	10
#define XLOG_HEADER_MAGIC_NUM	0xFEEDbabe	/* Invalid cycle number */
#define XLOG_VERSION_1		1
#define XLOG_VERSION_2		2		/* Large IClogs, Log sunit */
#define XLOG_VERSION_OKBITS	(XLOG_VERSION_1 | XLOG_VERSION_2)
#define XLOG_RECORD_BSIZE	(16*1024)	/* eventually 32k */
#define XLOG_BIG_RECORD_BSIZE	(32*1024)	/* 32k buffers */
#define XLOG_MAX_RECORD_BSIZE	(256*1024)
#define XLOG_HEADER_CYCLE_SIZE	(32*1024)	/* cycle data in header */
#define XLOG_RECORD_BSHIFT	14		/* 16384 == 1 << 14 */
#define XLOG_BIG_RECORD_BSHIFT	15		/* 32k == 1 << 15 */
#define XLOG_MAX_RECORD_BSHIFT	18		/* 256k == 1 << 18 */
#define XLOG_BTOLSUNIT(log, b)  (((b)+(log)->l_mp->m_sb.sb_logsunit-1) / \
                                 (log)->l_mp->m_sb.sb_logsunit)
#define XLOG_LSUNITTOB(log, su) ((su) * (log)->l_mp->m_sb.sb_logsunit)

#define XLOG_HEADER_SIZE	512

#define XLOG_REC_SHIFT(log) \
	BTOBB(1 << (XFS_SB_VERSION_HASLOGV2(&log->l_mp->m_sb) ? \
	 XLOG_MAX_RECORD_BSHIFT : XLOG_BIG_RECORD_BSHIFT))
#define XLOG_TOTAL_REC_SHIFT(log) \
	BTOBB(XLOG_MAX_ICLOGS << (XFS_SB_VERSION_HASLOGV2(&log->l_mp->m_sb) ? \
	 XLOG_MAX_RECORD_BSHIFT : XLOG_BIG_RECORD_BSHIFT))

/*
 *  set lsns
 */

#define ASSIGN_ANY_LSN_HOST(lsn,cycle,block)  \
    { \
	(lsn) = ((xfs_lsn_t)(cycle)<<32)|(block); \
    }
#define ASSIGN_ANY_LSN_DISK(lsn,cycle,block)  \
    { \
	INT_SET(((uint *)&(lsn))[0], ARCH_CONVERT, (cycle)); \
	INT_SET(((uint *)&(lsn))[1], ARCH_CONVERT, (block)); \
    }
#define ASSIGN_LSN(lsn,log) \
    ASSIGN_ANY_LSN_DISK(lsn,(log)->l_curr_cycle,(log)->l_curr_block);

#define XLOG_SET(f,b)		(((f) & (b)) == (b))

#define GET_CYCLE(ptr, arch) \
    (INT_GET(*(uint *)(ptr), arch) == XLOG_HEADER_MAGIC_NUM ? \
	 INT_GET(*((uint *)(ptr)+1), arch) : \
	 INT_GET(*(uint *)(ptr), arch) \
    )

#define BLK_AVG(blk1, blk2)	((blk1+blk2) >> 1)


#ifdef __KERNEL__

/*
 * get client id from packed copy.
 *
 * this hack is here because the xlog_pack code copies four bytes
 * of xlog_op_header containing the fields oh_clientid, oh_flags
 * and oh_res2 into the packed copy.
 *
 * later on this four byte chunk is treated as an int and the
 * client id is pulled out.
 *
 * this has endian issues, of course.
 */

#ifndef XFS_NATIVE_HOST
#define GET_CLIENT_ID(i,arch) \
    ((i) & 0xff)
#else
#define GET_CLIENT_ID(i,arch) \
    ((i) >> 24)
#endif

#define GRANT_LOCK(log)		mutex_spinlock(&(log)->l_grant_lock)
#define GRANT_UNLOCK(log, s)	mutex_spinunlock(&(log)->l_grant_lock, s)
#define LOG_LOCK(log)		mutex_spinlock(&(log)->l_icloglock)
#define LOG_UNLOCK(log, s)	mutex_spinunlock(&(log)->l_icloglock, s)

#define xlog_panic(args...)	cmn_err(CE_PANIC, ## args)
#define xlog_exit(args...)	cmn_err(CE_PANIC, ## args)
#define xlog_warn(args...)	cmn_err(CE_WARN, ## args)

/*
 * In core log state
 */
#define XLOG_STATE_ACTIVE    0x0001 /* Current IC log being written to */
#define XLOG_STATE_WANT_SYNC 0x0002 /* Want to sync this iclog; no more writes */
#define XLOG_STATE_SYNCING   0x0004 /* This IC log is syncing */
#define XLOG_STATE_DONE_SYNC 0x0008 /* Done syncing to disk */
#define XLOG_STATE_DO_CALLBACK \
			     0x0010 /* Process callback functions */
#define XLOG_STATE_CALLBACK  0x0020 /* Callback functions now */
#define XLOG_STATE_DIRTY     0x0040 /* Dirty IC log, not ready for ACTIVE status*/
#define XLOG_STATE_IOERROR   0x0080 /* IO error happened in sync'ing log */
#define XLOG_STATE_ALL	     0x7FFF /* All possible valid flags */
#define XLOG_STATE_NOTUSED   0x8000 /* This IC log not being used */
#endif	/* __KERNEL__ */

/*
 * Flags to log operation header
 *
 * The first write of a new transaction will be preceded with a start
 * record, XLOG_START_TRANS.  Once a transaction is committed, a commit
 * record is written, XLOG_COMMIT_TRANS.  If a single region can not fit into
 * the remainder of the current active in-core log, it is split up into
 * multiple regions.  Each partial region will be marked with a
 * XLOG_CONTINUE_TRANS until the last one, which gets marked with XLOG_END_TRANS.
 *
 */
#define XLOG_START_TRANS	0x01	/* Start a new transaction */
#define XLOG_COMMIT_TRANS	0x02	/* Commit this transaction */
#define XLOG_CONTINUE_TRANS	0x04	/* Cont this trans into new region */
#define XLOG_WAS_CONT_TRANS	0x08	/* Cont this trans into new region */
#define XLOG_END_TRANS		0x10	/* End a continued transaction */
#define XLOG_UNMOUNT_TRANS	0x20	/* Unmount a filesystem transaction */
#define XLOG_SKIP_TRANS		(XLOG_COMMIT_TRANS | XLOG_CONTINUE_TRANS | \
				 XLOG_WAS_CONT_TRANS | XLOG_END_TRANS | \
				 XLOG_UNMOUNT_TRANS)

#ifdef __KERNEL__
/*
 * Flags to log ticket
 */
#define XLOG_TIC_INITED		0x1	/* has been initialized */
#define XLOG_TIC_PERM_RESERV	0x2	/* permanent reservation */
#define XLOG_TIC_IN_Q		0x4
#endif	/* __KERNEL__ */

#define XLOG_UNMOUNT_TYPE	0x556e	/* Un for Unmount */

/*
 * Flags for log structure
 */
#define XLOG_CHKSUM_MISMATCH	0x1	/* used only during recovery */
#define XLOG_ACTIVE_RECOVERY	0x2	/* in the middle of recovery */
#define	XLOG_RECOVERY_NEEDED	0x4	/* log was recovered */
#define XLOG_IO_ERROR		0x8	/* log hit an I/O error, and being
					   shutdown */
typedef __uint32_t xlog_tid_t;


#ifdef __KERNEL__
/*
 * Below are states for covering allocation transactions.
 * By covering, we mean changing the h_tail_lsn in the last on-disk
 * log write such that no allocation transactions will be re-done during
 * recovery after a system crash. Recovery starts at the last on-disk
 * log write.
 *
 * These states are used to insert dummy log entries to cover
 * space allocation transactions which can undo non-transactional changes
 * after a crash. Writes to a file with space
 * already allocated do not result in any transactions. Allocations
 * might include space beyond the EOF. So if we just push the EOF a
 * little, the last transaction for the file could contain the wrong
 * size. If there is no file system activity, after an allocation
 * transaction, and the system crashes, the allocation transaction
 * will get replayed and the file will be truncated. This could
 * be hours/days/... after the allocation occurred.
 *
 * The fix for this is to do two dummy transactions when the
 * system is idle. We need two dummy transaction because the h_tail_lsn
 * in the log record header needs to point beyond the last possible
 * non-dummy transaction. The first dummy changes the h_tail_lsn to
 * the first transaction before the dummy. The second dummy causes
 * h_tail_lsn to point to the first dummy. Recovery starts at h_tail_lsn.
 *
 * These dummy transactions get committed when everything
 * is idle (after there has been some activity).
 *
 * There are 5 states used to control this.
 *
 *  IDLE -- no logging has been done on the file system or
 *		we are done covering previous transactions.
 *  NEED -- logging has occurred and we need a dummy transaction
 *		when the log becomes idle.
 *  DONE -- we were in the NEED state and have committed a dummy
 *		transaction.
 *  NEED2 -- we detected that a dummy transaction has gone to the
 *		on disk log with no other transactions.
 *  DONE2 -- we committed a dummy transaction when in the NEED2 state.
 *
 * There are two places where we switch states:
 *
 * 1.) In xfs_sync, when we detect an idle log and are in NEED or NEED2.
 *	We commit the dummy transaction and switch to DONE or DONE2,
 *	respectively. In all other states, we don't do anything.
 *
 * 2.) When we finish writing the on-disk log (xlog_state_clean_log).
 *
 *	No matter what state we are in, if this isn't the dummy
 *	transaction going out, the next state is NEED.
 *	So, if we aren't in the DONE or DONE2 states, the next state
 *	is NEED. We can't be finishing a write of the dummy record
 *	unless it was committed and the state switched to DONE or DONE2.
 *
 *	If we are in the DONE state and this was a write of the
 *		dummy transaction, we move to NEED2.
 *
 *	If we are in the DONE2 state and this was a write of the
 *		dummy transaction, we move to IDLE.
 *
 *
 * Writing only one dummy transaction can get appended to
 * one file space allocation. When this happens, the log recovery
 * code replays the space allocation and a file could be truncated.
 * This is why we have the NEED2 and DONE2 states before going idle.
 */

#define XLOG_STATE_COVER_IDLE	0
#define XLOG_STATE_COVER_NEED	1
#define XLOG_STATE_COVER_DONE	2
#define XLOG_STATE_COVER_NEED2	3
#define XLOG_STATE_COVER_DONE2	4

#define XLOG_COVER_OPS		5


/* Ticket reservation region accounting */ 
#define XLOG_TIC_LEN_MAX	15
#define XLOG_TIC_RESET_RES(t) ((t)->t_res_num = \
				(t)->t_res_arr_sum = (t)->t_res_num_ophdrs = 0)
#define XLOG_TIC_ADD_OPHDR(t) ((t)->t_res_num_ophdrs++)
#define XLOG_TIC_ADD_REGION(t, len, type)				\
	do {								\
		if ((t)->t_res_num == XLOG_TIC_LEN_MAX) { 		\
			/* add to overflow and start again */		\
			(t)->t_res_o_flow += (t)->t_res_arr_sum;	\
			(t)->t_res_num = 0;				\
			(t)->t_res_arr_sum = 0;				\
		}							\
		(t)->t_res_arr[(t)->t_res_num].r_len = (len);		\
		(t)->t_res_arr[(t)->t_res_num].r_type = (type);		\
		(t)->t_res_arr_sum += (len);				\
		(t)->t_res_num++;					\
	} while (0)

/*
 * Reservation region
 * As would be stored in xfs_log_iovec but without the i_addr which
 * we don't care about.
 */
typedef struct xlog_res {
	uint	r_len;	/* region length		:4 */
	uint	r_type;	/* region's transaction type	:4 */
} xlog_res_t;

typedef struct xlog_ticket {
	sv_t		   t_sema;	 /* sleep on this semaphore      : 20 */
 	struct xlog_ticket *t_next;	 /*			         :4|8 */
	struct xlog_ticket *t_prev;	 /*				 :4|8 */
	xlog_tid_t	   t_tid;	 /* transaction identifier	 : 4  */
	int		   t_curr_res;	 /* current reservation in bytes : 4  */
	int		   t_unit_res;	 /* unit reservation in bytes    : 4  */
	char		   t_ocnt;	 /* original count		 : 1  */
	char		   t_cnt;	 /* current count		 : 1  */
	char		   t_clientid;	 /* who does this belong to;	 : 1  */
	char		   t_flags;	 /* properties of reservation	 : 1  */
	uint		   t_trans_type; /* transaction type             : 4  */

        /* reservation array fields */
	uint		   t_res_num;                    /* num in array : 4 */
	uint		   t_res_num_ophdrs;		 /* num op hdrs  : 4 */
	uint		   t_res_arr_sum;		 /* array sum    : 4 */
	uint		   t_res_o_flow;		 /* sum overflow : 4 */
	xlog_res_t	   t_res_arr[XLOG_TIC_LEN_MAX];  /* array of res : 8 * 15 */ 
} xlog_ticket_t;

#endif


typedef struct xlog_op_header {
	xlog_tid_t oh_tid;	/* transaction id of operation	:  4 b */
	int	   oh_len;	/* bytes in data region		:  4 b */
	__uint8_t  oh_clientid;	/* who sent me this		:  1 b */
	__uint8_t  oh_flags;	/*				:  1 b */
	ushort	   oh_res2;	/* 32 bit align			:  2 b */
} xlog_op_header_t;


/* valid values for h_fmt */
#define XLOG_FMT_UNKNOWN  0
#define XLOG_FMT_LINUX_LE 1
#define XLOG_FMT_LINUX_BE 2
#define XLOG_FMT_IRIX_BE  3

/* our fmt */
#ifdef XFS_NATIVE_HOST
#define XLOG_FMT XLOG_FMT_LINUX_BE
#else
#define XLOG_FMT XLOG_FMT_LINUX_LE
#endif

typedef struct xlog_rec_header {
	uint	  h_magicno;	/* log record (LR) identifier		:  4 */
	uint	  h_cycle;	/* write cycle of log			:  4 */
	int	  h_version;	/* LR version				:  4 */
	int	  h_len;	/* len in bytes; should be 64-bit aligned: 4 */
	xfs_lsn_t h_lsn;	/* lsn of this LR			:  8 */
	xfs_lsn_t h_tail_lsn;	/* lsn of 1st LR w/ buffers not committed: 8 */
	uint	  h_chksum;	/* may not be used; non-zero if used	:  4 */
	int	  h_prev_block; /* block number to previous LR		:  4 */
	int	  h_num_logops;	/* number of log operations in this LR	:  4 */
	uint	  h_cycle_data[XLOG_HEADER_CYCLE_SIZE / BBSIZE];
	/* new fields */
	int       h_fmt;        /* format of log record                 :  4 */
	uuid_t    h_fs_uuid;    /* uuid of FS                           : 16 */
	int       h_size;	/* iclog size				:  4 */
} xlog_rec_header_t;

typedef struct xlog_rec_ext_header {
	uint	  xh_cycle;	/* write cycle of log			: 4 */
	uint	  xh_cycle_data[XLOG_HEADER_CYCLE_SIZE / BBSIZE]; /*	: 256 */
} xlog_rec_ext_header_t;

#ifdef __KERNEL__
/*
 * - A log record header is 512 bytes.  There is plenty of room to grow the
 *	xlog_rec_header_t into the reserved space.
 * - ic_data follows, so a write to disk can start at the beginning of
 *	the iclog.
 * - ic_forcesema is used to implement synchronous forcing of the iclog to disk.
 * - ic_next is the pointer to the next iclog in the ring.
 * - ic_bp is a pointer to the buffer used to write this incore log to disk.
 * - ic_log is a pointer back to the global log structure.
 * - ic_callback is a linked list of callback function/argument pairs to be
 *	called after an iclog finishes writing.
 * - ic_size is the full size of the header plus data.
 * - ic_offset is the current number of bytes written to in this iclog.
 * - ic_refcnt is bumped when someone is writing to the log.
 * - ic_state is the state of the iclog.
 */
typedef struct xlog_iclog_fields {
	sv_t			ic_forcesema;
	sv_t			ic_writesema;
	struct xlog_in_core	*ic_next;
	struct xlog_in_core	*ic_prev;
	struct xfs_buf		*ic_bp;
	struct log		*ic_log;
	xfs_log_callback_t	*ic_callback;
	xfs_log_callback_t	**ic_callback_tail;
#ifdef XFS_LOG_TRACE
	struct ktrace		*ic_trace;
#endif
	int			ic_size;
	int			ic_offset;
	int			ic_refcnt;
	int			ic_bwritecnt;
	ushort_t		ic_state;
	char			*ic_datap;	/* pointer to iclog data */
} xlog_iclog_fields_t;

typedef union xlog_in_core2 {
	xlog_rec_header_t	hic_header;
	xlog_rec_ext_header_t	hic_xheader;
	char			hic_sector[XLOG_HEADER_SIZE];
} xlog_in_core_2_t;

typedef struct xlog_in_core {
	xlog_iclog_fields_t	hic_fields;
	xlog_in_core_2_t	*hic_data;
} xlog_in_core_t;

/*
 * Defines to save our code from this glop.
 */
#define	ic_forcesema	hic_fields.ic_forcesema
#define ic_writesema	hic_fields.ic_writesema
#define	ic_next		hic_fields.ic_next
#define	ic_prev		hic_fields.ic_prev
#define	ic_bp		hic_fields.ic_bp
#define	ic_log		hic_fields.ic_log
#define	ic_callback	hic_fields.ic_callback
#define	ic_callback_tail hic_fields.ic_callback_tail
#define	ic_trace	hic_fields.ic_trace
#define	ic_size		hic_fields.ic_size
#define	ic_offset	hic_fields.ic_offset
#define	ic_refcnt	hic_fields.ic_refcnt
#define	ic_bwritecnt	hic_fields.ic_bwritecnt
#define	ic_state	hic_fields.ic_state
#define ic_datap	hic_fields.ic_datap
#define ic_header	hic_data->hic_header

/*
 * The reservation head lsn is not made up of a cycle number and block number.
 * Instead, it uses a cycle number and byte number.  Logs don't expect to
 * overflow 31 bits worth of byte offset, so using a byte number will mean
 * that round off problems won't occur when releasing partial reservations.
 */
typedef struct log {
	/* The following block of fields are changed while holding icloglock */
	sema_t			l_flushsema;    /* iclog flushing semaphore */
	int			l_flushcnt;	/* # of procs waiting on this
						 * sema */
	int			l_ticket_cnt;	/* free ticket count */
	int			l_ticket_tcnt;	/* total ticket count */
	int			l_covered_state;/* state of "covering disk
						 * log entries" */
	xlog_ticket_t		*l_freelist;    /* free list of tickets */
	xlog_ticket_t		*l_unmount_free;/* kmem_free these addresses */
	xlog_ticket_t		*l_tail;        /* free list of tickets */
	xlog_in_core_t		*l_iclog;       /* head log queue	*/
	lock_t			l_icloglock;    /* grab to change iclog state */
	xfs_lsn_t		l_tail_lsn;     /* lsn of 1st LR with unflushed
						 * buffers */
	xfs_lsn_t		l_last_sync_lsn;/* lsn of last LR on disk */
	struct xfs_mount	*l_mp;	        /* mount point */
	struct xfs_buf		*l_xbuf;        /* extra buffer for log
						 * wrapping */
	struct xfs_buftarg	*l_targ;        /* buftarg of log */
	xfs_daddr_t		l_logBBstart;   /* start block of log */
	int			l_logsize;      /* size of log in bytes */
	int			l_logBBsize;    /* size of log in BB chunks */
	int			l_curr_cycle;   /* Cycle number of log writes */
	int			l_prev_cycle;   /* Cycle number before last
						 * block increment */
	int			l_curr_block;   /* current logical log block */
	int			l_prev_block;   /* previous logical log block */
	int			l_iclog_size;	/* size of log in bytes */
	int			l_iclog_size_log; /* log power size of log */
	int			l_iclog_bufs;	/* number of iclog buffers */

	/* The following field are used for debugging; need to hold icloglock */
	char			*l_iclog_bak[XLOG_MAX_ICLOGS];

	/* The following block of fields are changed while holding grant_lock */
	lock_t			l_grant_lock;
	xlog_ticket_t		*l_reserve_headq;
	xlog_ticket_t		*l_write_headq;
	int			l_grant_reserve_cycle;
	int			l_grant_reserve_bytes;
	int			l_grant_write_cycle;
	int			l_grant_write_bytes;

	/* The following fields don't need locking */
#ifdef XFS_LOG_TRACE
	struct ktrace		*l_trace;
	struct ktrace		*l_grant_trace;
#endif
	uint			l_flags;
	uint			l_quotaoffs_flag; /* XFS_DQ_*, for QUOTAOFFs */
	struct xfs_buf_cancel	**l_buf_cancel_table;
	int			l_iclog_hsize;  /* size of iclog header */
	int			l_iclog_heads;  /* # of iclog header sectors */
	uint			l_sectbb_log;   /* log2 of sector size in BBs */
	uint			l_sectbb_mask;  /* sector size (in BBs)
						 * alignment mask */
} xlog_t;

#define XLOG_FORCED_SHUTDOWN(log)	((log)->l_flags & XLOG_IO_ERROR)


/* common routines */
extern xfs_lsn_t xlog_assign_tail_lsn(struct xfs_mount *mp);
extern int	 xlog_find_tail(xlog_t	*log,
				xfs_daddr_t *head_blk,
				xfs_daddr_t *tail_blk);
extern int	 xlog_recover(xlog_t *log);
extern int	 xlog_recover_finish(xlog_t *log, int mfsi_flags);
extern void	 xlog_pack_data(xlog_t *log, xlog_in_core_t *iclog, int);
extern void	 xlog_recover_process_iunlinks(xlog_t *log);

extern struct xfs_buf *xlog_get_bp(xlog_t *, int);
extern void	 xlog_put_bp(struct xfs_buf *);
extern int	 xlog_bread(xlog_t *, xfs_daddr_t, int, struct xfs_buf *);

/* iclog tracing */
#define XLOG_TRACE_GRAB_FLUSH  1
#define XLOG_TRACE_REL_FLUSH   2
#define XLOG_TRACE_SLEEP_FLUSH 3
#define XLOG_TRACE_WAKE_FLUSH  4

#endif	/* __KERNEL__ */

#endif	/* __XFS_LOG_PRIV_H__ */