xref: /linux/fs/xfs/xfs_log_priv.h (revision 2624f124b3b5d550ab2fbef7ee3bc0e1fed09722)
1 /*
2  * Copyright (c) 2000-2003 Silicon Graphics, Inc.  All Rights Reserved.
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms of version 2 of the GNU General Public License as
6  * published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it would be useful, but
9  * WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
11  *
12  * Further, this software is distributed without any warranty that it is
13  * free of the rightful claim of any third person regarding infringement
14  * or the like.  Any license provided herein, whether implied or
15  * otherwise, applies only to this software file.  Patent licenses, if
16  * any, provided herein do not apply to combinations of this program with
17  * other software, or any other product whatsoever.
18  *
19  * You should have received a copy of the GNU General Public License along
20  * with this program; if not, write the Free Software Foundation, Inc., 59
21  * Temple Place - Suite 330, Boston MA 02111-1307, USA.
22  *
23  * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
24  * Mountain View, CA  94043, or:
25  *
26  * http://www.sgi.com
27  *
28  * For further information regarding this notice, see:
29  *
30  * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
31  */
32 #ifndef	__XFS_LOG_PRIV_H__
33 #define __XFS_LOG_PRIV_H__
34 
35 struct xfs_buf;
36 struct ktrace;
37 struct log;
38 struct xfs_buf_cancel;
39 struct xfs_mount;
40 
41 /*
42  * Macros, structures, prototypes for internal log manager use.
43  */
44 
45 #define XLOG_MIN_ICLOGS		2
46 #define XLOG_MED_ICLOGS		4
47 #define XLOG_MAX_ICLOGS		8
48 #define XLOG_CALLBACK_SIZE	10
49 #define XLOG_HEADER_MAGIC_NUM	0xFEEDbabe	/* Invalid cycle number */
50 #define XLOG_VERSION_1		1
51 #define XLOG_VERSION_2		2		/* Large IClogs, Log sunit */
52 #define XLOG_VERSION_OKBITS	(XLOG_VERSION_1 | XLOG_VERSION_2)
53 #define XLOG_RECORD_BSIZE	(16*1024)	/* eventually 32k */
54 #define XLOG_BIG_RECORD_BSIZE	(32*1024)	/* 32k buffers */
55 #define XLOG_MAX_RECORD_BSIZE	(256*1024)
56 #define XLOG_HEADER_CYCLE_SIZE	(32*1024)	/* cycle data in header */
57 #define XLOG_RECORD_BSHIFT	14		/* 16384 == 1 << 14 */
58 #define XLOG_BIG_RECORD_BSHIFT	15		/* 32k == 1 << 15 */
59 #define XLOG_MAX_RECORD_BSHIFT	18		/* 256k == 1 << 18 */
60 #define XLOG_BTOLSUNIT(log, b)  (((b)+(log)->l_mp->m_sb.sb_logsunit-1) / \
61                                  (log)->l_mp->m_sb.sb_logsunit)
62 #define XLOG_LSUNITTOB(log, su) ((su) * (log)->l_mp->m_sb.sb_logsunit)
63 
64 #define XLOG_HEADER_SIZE	512
65 
66 #define XLOG_REC_SHIFT(log) \
67 	BTOBB(1 << (XFS_SB_VERSION_HASLOGV2(&log->l_mp->m_sb) ? \
68 	 XLOG_MAX_RECORD_BSHIFT : XLOG_BIG_RECORD_BSHIFT))
69 #define XLOG_TOTAL_REC_SHIFT(log) \
70 	BTOBB(XLOG_MAX_ICLOGS << (XFS_SB_VERSION_HASLOGV2(&log->l_mp->m_sb) ? \
71 	 XLOG_MAX_RECORD_BSHIFT : XLOG_BIG_RECORD_BSHIFT))
72 
73 /*
74  *  set lsns
75  */
76 
77 #define ASSIGN_ANY_LSN_HOST(lsn,cycle,block)  \
78     { \
79 	(lsn) = ((xfs_lsn_t)(cycle)<<32)|(block); \
80     }
81 #define ASSIGN_ANY_LSN_DISK(lsn,cycle,block)  \
82     { \
83 	INT_SET(((uint *)&(lsn))[0], ARCH_CONVERT, (cycle)); \
84 	INT_SET(((uint *)&(lsn))[1], ARCH_CONVERT, (block)); \
85     }
86 #define ASSIGN_LSN(lsn,log) \
87     ASSIGN_ANY_LSN_DISK(lsn,(log)->l_curr_cycle,(log)->l_curr_block);
88 
89 #define XLOG_SET(f,b)		(((f) & (b)) == (b))
90 
91 #define GET_CYCLE(ptr, arch) \
92     (INT_GET(*(uint *)(ptr), arch) == XLOG_HEADER_MAGIC_NUM ? \
93 	 INT_GET(*((uint *)(ptr)+1), arch) : \
94 	 INT_GET(*(uint *)(ptr), arch) \
95     )
96 
97 #define BLK_AVG(blk1, blk2)	((blk1+blk2) >> 1)
98 
99 
100 #ifdef __KERNEL__
101 
102 /*
103  * get client id from packed copy.
104  *
105  * this hack is here because the xlog_pack code copies four bytes
106  * of xlog_op_header containing the fields oh_clientid, oh_flags
107  * and oh_res2 into the packed copy.
108  *
109  * later on this four byte chunk is treated as an int and the
110  * client id is pulled out.
111  *
112  * this has endian issues, of course.
113  */
114 
115 #ifndef XFS_NATIVE_HOST
116 #define GET_CLIENT_ID(i,arch) \
117     ((i) & 0xff)
118 #else
119 #define GET_CLIENT_ID(i,arch) \
120     ((i) >> 24)
121 #endif
122 
123 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XLOG_GRANT_SUB_SPACE)
124 void xlog_grant_sub_space(struct log *log, int bytes, int type);
125 #define XLOG_GRANT_SUB_SPACE(log,bytes,type)	\
126 	xlog_grant_sub_space(log,bytes,type)
127 #else
128 #define XLOG_GRANT_SUB_SPACE(log,bytes,type)				\
129     {									\
130 	if (type == 'w') {						\
131 		(log)->l_grant_write_bytes -= (bytes);			\
132 		if ((log)->l_grant_write_bytes < 0) {			\
133 			(log)->l_grant_write_bytes += (log)->l_logsize;	\
134 			(log)->l_grant_write_cycle--;			\
135 		}							\
136 	} else {							\
137 		(log)->l_grant_reserve_bytes -= (bytes);		\
138 		if ((log)->l_grant_reserve_bytes < 0) {			\
139 			(log)->l_grant_reserve_bytes += (log)->l_logsize;\
140 			(log)->l_grant_reserve_cycle--;			\
141 		}							\
142 	 }								\
143     }
144 #endif
145 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XLOG_GRANT_ADD_SPACE)
146 void xlog_grant_add_space(struct log *log, int bytes, int type);
147 #define XLOG_GRANT_ADD_SPACE(log,bytes,type)	\
148 	xlog_grant_add_space(log,bytes,type)
149 #else
150 #define XLOG_GRANT_ADD_SPACE(log,bytes,type)				\
151     {									\
152 	if (type == 'w') {						\
153 		(log)->l_grant_write_bytes += (bytes);			\
154 		if ((log)->l_grant_write_bytes > (log)->l_logsize) {	\
155 			(log)->l_grant_write_bytes -= (log)->l_logsize;	\
156 			(log)->l_grant_write_cycle++;			\
157 		}							\
158 	} else {							\
159 		(log)->l_grant_reserve_bytes += (bytes);		\
160 		if ((log)->l_grant_reserve_bytes > (log)->l_logsize) {	\
161 			(log)->l_grant_reserve_bytes -= (log)->l_logsize;\
162 			(log)->l_grant_reserve_cycle++;			\
163 		}							\
164 	 }								\
165     }
166 #endif
167 #define XLOG_INS_TICKETQ(q,tic)				\
168     {							\
169 	if (q) {					\
170 		(tic)->t_next	    = (q);		\
171 		(tic)->t_prev	    = (q)->t_prev;	\
172 		(q)->t_prev->t_next = (tic);		\
173 		(q)->t_prev	    = (tic);		\
174 	} else {					\
175 		(tic)->t_prev = (tic)->t_next = (tic);	\
176 		(q) = (tic);				\
177 	}						\
178 	(tic)->t_flags |= XLOG_TIC_IN_Q;		\
179     }
180 #define XLOG_DEL_TICKETQ(q,tic)				\
181     {							\
182 	if ((tic) == (tic)->t_next) {			\
183 		(q) = NULL;				\
184 	} else {					\
185 		(q) = (tic)->t_next;			\
186 		(tic)->t_next->t_prev = (tic)->t_prev;	\
187 		(tic)->t_prev->t_next = (tic)->t_next;	\
188 	}						\
189 	(tic)->t_next = (tic)->t_prev = NULL;		\
190 	(tic)->t_flags &= ~XLOG_TIC_IN_Q;		\
191     }
192 
193 
194 #define GRANT_LOCK(log)		mutex_spinlock(&(log)->l_grant_lock)
195 #define GRANT_UNLOCK(log, s)	mutex_spinunlock(&(log)->l_grant_lock, s)
196 #define LOG_LOCK(log)		mutex_spinlock(&(log)->l_icloglock)
197 #define LOG_UNLOCK(log, s)	mutex_spinunlock(&(log)->l_icloglock, s)
198 
199 #define xlog_panic(args...)	cmn_err(CE_PANIC, ## args)
200 #define xlog_exit(args...)	cmn_err(CE_PANIC, ## args)
201 #define xlog_warn(args...)	cmn_err(CE_WARN, ## args)
202 
203 /*
204  * In core log state
205  */
206 #define XLOG_STATE_ACTIVE    0x0001 /* Current IC log being written to */
207 #define XLOG_STATE_WANT_SYNC 0x0002 /* Want to sync this iclog; no more writes */
208 #define XLOG_STATE_SYNCING   0x0004 /* This IC log is syncing */
209 #define XLOG_STATE_DONE_SYNC 0x0008 /* Done syncing to disk */
210 #define XLOG_STATE_DO_CALLBACK \
211 			     0x0010 /* Process callback functions */
212 #define XLOG_STATE_CALLBACK  0x0020 /* Callback functions now */
213 #define XLOG_STATE_DIRTY     0x0040 /* Dirty IC log, not ready for ACTIVE status*/
214 #define XLOG_STATE_IOERROR   0x0080 /* IO error happened in sync'ing log */
215 #define XLOG_STATE_ALL	     0x7FFF /* All possible valid flags */
216 #define XLOG_STATE_NOTUSED   0x8000 /* This IC log not being used */
217 #endif	/* __KERNEL__ */
218 
219 /*
220  * Flags to log operation header
221  *
222  * The first write of a new transaction will be preceded with a start
223  * record, XLOG_START_TRANS.  Once a transaction is committed, a commit
224  * record is written, XLOG_COMMIT_TRANS.  If a single region can not fit into
225  * the remainder of the current active in-core log, it is split up into
226  * multiple regions.  Each partial region will be marked with a
227  * XLOG_CONTINUE_TRANS until the last one, which gets marked with XLOG_END_TRANS.
228  *
229  */
230 #define XLOG_START_TRANS	0x01	/* Start a new transaction */
231 #define XLOG_COMMIT_TRANS	0x02	/* Commit this transaction */
232 #define XLOG_CONTINUE_TRANS	0x04	/* Cont this trans into new region */
233 #define XLOG_WAS_CONT_TRANS	0x08	/* Cont this trans into new region */
234 #define XLOG_END_TRANS		0x10	/* End a continued transaction */
235 #define XLOG_UNMOUNT_TRANS	0x20	/* Unmount a filesystem transaction */
236 #define XLOG_SKIP_TRANS		(XLOG_COMMIT_TRANS | XLOG_CONTINUE_TRANS | \
237 				 XLOG_WAS_CONT_TRANS | XLOG_END_TRANS | \
238 				 XLOG_UNMOUNT_TRANS)
239 
240 #ifdef __KERNEL__
241 /*
242  * Flags to log ticket
243  */
244 #define XLOG_TIC_INITED		0x1	/* has been initialized */
245 #define XLOG_TIC_PERM_RESERV	0x2	/* permanent reservation */
246 #define XLOG_TIC_IN_Q		0x4
247 #endif	/* __KERNEL__ */
248 
249 #define XLOG_UNMOUNT_TYPE	0x556e	/* Un for Unmount */
250 
251 /*
252  * Flags for log structure
253  */
254 #define XLOG_CHKSUM_MISMATCH	0x1	/* used only during recovery */
255 #define XLOG_ACTIVE_RECOVERY	0x2	/* in the middle of recovery */
256 #define	XLOG_RECOVERY_NEEDED	0x4	/* log was recovered */
257 #define XLOG_IO_ERROR		0x8	/* log hit an I/O error, and being
258 					   shutdown */
259 typedef __uint32_t xlog_tid_t;
260 
261 
262 #ifdef __KERNEL__
263 /*
264  * Below are states for covering allocation transactions.
265  * By covering, we mean changing the h_tail_lsn in the last on-disk
266  * log write such that no allocation transactions will be re-done during
267  * recovery after a system crash. Recovery starts at the last on-disk
268  * log write.
269  *
270  * These states are used to insert dummy log entries to cover
271  * space allocation transactions which can undo non-transactional changes
272  * after a crash. Writes to a file with space
273  * already allocated do not result in any transactions. Allocations
274  * might include space beyond the EOF. So if we just push the EOF a
275  * little, the last transaction for the file could contain the wrong
276  * size. If there is no file system activity, after an allocation
277  * transaction, and the system crashes, the allocation transaction
278  * will get replayed and the file will be truncated. This could
279  * be hours/days/... after the allocation occurred.
280  *
281  * The fix for this is to do two dummy transactions when the
282  * system is idle. We need two dummy transaction because the h_tail_lsn
283  * in the log record header needs to point beyond the last possible
284  * non-dummy transaction. The first dummy changes the h_tail_lsn to
285  * the first transaction before the dummy. The second dummy causes
286  * h_tail_lsn to point to the first dummy. Recovery starts at h_tail_lsn.
287  *
288  * These dummy transactions get committed when everything
289  * is idle (after there has been some activity).
290  *
291  * There are 5 states used to control this.
292  *
293  *  IDLE -- no logging has been done on the file system or
294  *		we are done covering previous transactions.
295  *  NEED -- logging has occurred and we need a dummy transaction
296  *		when the log becomes idle.
297  *  DONE -- we were in the NEED state and have committed a dummy
298  *		transaction.
299  *  NEED2 -- we detected that a dummy transaction has gone to the
300  *		on disk log with no other transactions.
301  *  DONE2 -- we committed a dummy transaction when in the NEED2 state.
302  *
303  * There are two places where we switch states:
304  *
305  * 1.) In xfs_sync, when we detect an idle log and are in NEED or NEED2.
306  *	We commit the dummy transaction and switch to DONE or DONE2,
307  *	respectively. In all other states, we don't do anything.
308  *
309  * 2.) When we finish writing the on-disk log (xlog_state_clean_log).
310  *
311  *	No matter what state we are in, if this isn't the dummy
312  *	transaction going out, the next state is NEED.
313  *	So, if we aren't in the DONE or DONE2 states, the next state
314  *	is NEED. We can't be finishing a write of the dummy record
315  *	unless it was committed and the state switched to DONE or DONE2.
316  *
317  *	If we are in the DONE state and this was a write of the
318  *		dummy transaction, we move to NEED2.
319  *
320  *	If we are in the DONE2 state and this was a write of the
321  *		dummy transaction, we move to IDLE.
322  *
323  *
324  * Writing only one dummy transaction can get appended to
325  * one file space allocation. When this happens, the log recovery
326  * code replays the space allocation and a file could be truncated.
327  * This is why we have the NEED2 and DONE2 states before going idle.
328  */
329 
330 #define XLOG_STATE_COVER_IDLE	0
331 #define XLOG_STATE_COVER_NEED	1
332 #define XLOG_STATE_COVER_DONE	2
333 #define XLOG_STATE_COVER_NEED2	3
334 #define XLOG_STATE_COVER_DONE2	4
335 
336 #define XLOG_COVER_OPS		5
337 
338 
339 /* Ticket reservation region accounting */
340 #if defined(XFS_LOG_RES_DEBUG)
341 #define XLOG_TIC_LEN_MAX	15
342 #define XLOG_TIC_RESET_RES(t) ((t)->t_res_num = \
343 				(t)->t_res_arr_sum = (t)->t_res_num_ophdrs = 0)
344 #define XLOG_TIC_ADD_OPHDR(t) ((t)->t_res_num_ophdrs++)
345 #define XLOG_TIC_ADD_REGION(t, len, type)				\
346 	do {								\
347 		if ((t)->t_res_num == XLOG_TIC_LEN_MAX) { 		\
348 			/* add to overflow and start again */		\
349 			(t)->t_res_o_flow += (t)->t_res_arr_sum;	\
350 			(t)->t_res_num = 0;				\
351 			(t)->t_res_arr_sum = 0;				\
352 		}							\
353 		(t)->t_res_arr[(t)->t_res_num].r_len = (len);		\
354 		(t)->t_res_arr[(t)->t_res_num].r_type = (type);		\
355 		(t)->t_res_arr_sum += (len);				\
356 		(t)->t_res_num++;					\
357 	} while (0)
358 
359 /*
360  * Reservation region
361  * As would be stored in xfs_log_iovec but without the i_addr which
362  * we don't care about.
363  */
364 typedef struct xlog_res {
365 	uint	r_len;
366 	uint	r_type;
367 } xlog_res_t;
368 #else
369 #define XLOG_TIC_RESET_RES(t)
370 #define XLOG_TIC_ADD_OPHDR(t)
371 #define XLOG_TIC_ADD_REGION(t, len, type)
372 #endif
373 
374 
375 typedef struct xlog_ticket {
376 	sv_t		   t_sema;	 /* sleep on this semaphore      : 20 */
377  	struct xlog_ticket *t_next;	 /*			         :4|8 */
378 	struct xlog_ticket *t_prev;	 /*				 :4|8 */
379 	xlog_tid_t	   t_tid;	 /* transaction identifier	 : 4  */
380 	int		   t_curr_res;	 /* current reservation in bytes : 4  */
381 	int		   t_unit_res;	 /* unit reservation in bytes    : 4  */
382 	char		   t_ocnt;	 /* original count		 : 1  */
383 	char		   t_cnt;	 /* current count		 : 1  */
384 	char		   t_clientid;	 /* who does this belong to;	 : 1  */
385 	char		   t_flags;	 /* properties of reservation	 : 1  */
386 	uint		   t_trans_type; /* transaction type             : 4  */
387 
388 #if defined (XFS_LOG_RES_DEBUG)
389         /* reservation array fields */
390 	uint		   t_res_num;                    /* num in array : 4 */
391 	xlog_res_t	   t_res_arr[XLOG_TIC_LEN_MAX];  /* array of res : X */
392 	uint		   t_res_num_ophdrs;		 /* num op hdrs  : 4 */
393 	uint		   t_res_arr_sum;		 /* array sum    : 4 */
394 	uint		   t_res_o_flow;		 /* sum overflow : 4 */
395 #endif
396 } xlog_ticket_t;
397 
398 #endif
399 
400 
401 typedef struct xlog_op_header {
402 	xlog_tid_t oh_tid;	/* transaction id of operation	:  4 b */
403 	int	   oh_len;	/* bytes in data region		:  4 b */
404 	__uint8_t  oh_clientid;	/* who sent me this		:  1 b */
405 	__uint8_t  oh_flags;	/*				:  1 b */
406 	ushort	   oh_res2;	/* 32 bit align			:  2 b */
407 } xlog_op_header_t;
408 
409 
410 /* valid values for h_fmt */
411 #define XLOG_FMT_UNKNOWN  0
412 #define XLOG_FMT_LINUX_LE 1
413 #define XLOG_FMT_LINUX_BE 2
414 #define XLOG_FMT_IRIX_BE  3
415 
416 /* our fmt */
417 #ifdef XFS_NATIVE_HOST
418 #define XLOG_FMT XLOG_FMT_LINUX_BE
419 #else
420 #define XLOG_FMT XLOG_FMT_LINUX_LE
421 #endif
422 
423 typedef struct xlog_rec_header {
424 	uint	  h_magicno;	/* log record (LR) identifier		:  4 */
425 	uint	  h_cycle;	/* write cycle of log			:  4 */
426 	int	  h_version;	/* LR version				:  4 */
427 	int	  h_len;	/* len in bytes; should be 64-bit aligned: 4 */
428 	xfs_lsn_t h_lsn;	/* lsn of this LR			:  8 */
429 	xfs_lsn_t h_tail_lsn;	/* lsn of 1st LR w/ buffers not committed: 8 */
430 	uint	  h_chksum;	/* may not be used; non-zero if used	:  4 */
431 	int	  h_prev_block; /* block number to previous LR		:  4 */
432 	int	  h_num_logops;	/* number of log operations in this LR	:  4 */
433 	uint	  h_cycle_data[XLOG_HEADER_CYCLE_SIZE / BBSIZE];
434 	/* new fields */
435 	int       h_fmt;        /* format of log record                 :  4 */
436 	uuid_t    h_fs_uuid;    /* uuid of FS                           : 16 */
437 	int       h_size;	/* iclog size				:  4 */
438 } xlog_rec_header_t;
439 
440 typedef struct xlog_rec_ext_header {
441 	uint	  xh_cycle;	/* write cycle of log			: 4 */
442 	uint	  xh_cycle_data[XLOG_HEADER_CYCLE_SIZE / BBSIZE]; /*	: 256 */
443 } xlog_rec_ext_header_t;
444 
445 #ifdef __KERNEL__
446 /*
447  * - A log record header is 512 bytes.  There is plenty of room to grow the
448  *	xlog_rec_header_t into the reserved space.
449  * - ic_data follows, so a write to disk can start at the beginning of
450  *	the iclog.
451  * - ic_forcesema is used to implement synchronous forcing of the iclog to disk.
452  * - ic_next is the pointer to the next iclog in the ring.
453  * - ic_bp is a pointer to the buffer used to write this incore log to disk.
454  * - ic_log is a pointer back to the global log structure.
455  * - ic_callback is a linked list of callback function/argument pairs to be
456  *	called after an iclog finishes writing.
457  * - ic_size is the full size of the header plus data.
458  * - ic_offset is the current number of bytes written to in this iclog.
459  * - ic_refcnt is bumped when someone is writing to the log.
460  * - ic_state is the state of the iclog.
461  */
462 typedef struct xlog_iclog_fields {
463 	sv_t			ic_forcesema;
464 	sv_t			ic_writesema;
465 	struct xlog_in_core	*ic_next;
466 	struct xlog_in_core	*ic_prev;
467 	struct xfs_buf		*ic_bp;
468 	struct log		*ic_log;
469 	xfs_log_callback_t	*ic_callback;
470 	xfs_log_callback_t	**ic_callback_tail;
471 #ifdef XFS_LOG_TRACE
472 	struct ktrace		*ic_trace;
473 #endif
474 	int			ic_size;
475 	int			ic_offset;
476 	int			ic_refcnt;
477 	int			ic_bwritecnt;
478 	ushort_t		ic_state;
479 	char			*ic_datap;	/* pointer to iclog data */
480 } xlog_iclog_fields_t;
481 
482 typedef union xlog_in_core2 {
483 	xlog_rec_header_t	hic_header;
484 	xlog_rec_ext_header_t	hic_xheader;
485 	char			hic_sector[XLOG_HEADER_SIZE];
486 } xlog_in_core_2_t;
487 
488 typedef struct xlog_in_core {
489 	xlog_iclog_fields_t	hic_fields;
490 	xlog_in_core_2_t	*hic_data;
491 } xlog_in_core_t;
492 
493 /*
494  * Defines to save our code from this glop.
495  */
496 #define	ic_forcesema	hic_fields.ic_forcesema
497 #define ic_writesema	hic_fields.ic_writesema
498 #define	ic_next		hic_fields.ic_next
499 #define	ic_prev		hic_fields.ic_prev
500 #define	ic_bp		hic_fields.ic_bp
501 #define	ic_log		hic_fields.ic_log
502 #define	ic_callback	hic_fields.ic_callback
503 #define	ic_callback_tail hic_fields.ic_callback_tail
504 #define	ic_trace	hic_fields.ic_trace
505 #define	ic_size		hic_fields.ic_size
506 #define	ic_offset	hic_fields.ic_offset
507 #define	ic_refcnt	hic_fields.ic_refcnt
508 #define	ic_bwritecnt	hic_fields.ic_bwritecnt
509 #define	ic_state	hic_fields.ic_state
510 #define ic_datap	hic_fields.ic_datap
511 #define ic_header	hic_data->hic_header
512 
513 /*
514  * The reservation head lsn is not made up of a cycle number and block number.
515  * Instead, it uses a cycle number and byte number.  Logs don't expect to
516  * overflow 31 bits worth of byte offset, so using a byte number will mean
517  * that round off problems won't occur when releasing partial reservations.
518  */
519 typedef struct log {
520 	/* The following block of fields are changed while holding icloglock */
521 	sema_t			l_flushsema;    /* iclog flushing semaphore */
522 	int			l_flushcnt;	/* # of procs waiting on this
523 						 * sema */
524 	int			l_ticket_cnt;	/* free ticket count */
525 	int			l_ticket_tcnt;	/* total ticket count */
526 	int			l_covered_state;/* state of "covering disk
527 						 * log entries" */
528 	xlog_ticket_t		*l_freelist;    /* free list of tickets */
529 	xlog_ticket_t		*l_unmount_free;/* kmem_free these addresses */
530 	xlog_ticket_t		*l_tail;        /* free list of tickets */
531 	xlog_in_core_t		*l_iclog;       /* head log queue	*/
532 	lock_t			l_icloglock;    /* grab to change iclog state */
533 	xfs_lsn_t		l_tail_lsn;     /* lsn of 1st LR with unflushed
534 						 * buffers */
535 	xfs_lsn_t		l_last_sync_lsn;/* lsn of last LR on disk */
536 	struct xfs_mount	*l_mp;	        /* mount point */
537 	struct xfs_buf		*l_xbuf;        /* extra buffer for log
538 						 * wrapping */
539 	struct xfs_buftarg	*l_targ;        /* buftarg of log */
540 	xfs_daddr_t		l_logBBstart;   /* start block of log */
541 	int			l_logsize;      /* size of log in bytes */
542 	int			l_logBBsize;    /* size of log in BB chunks */
543 	int			l_curr_cycle;   /* Cycle number of log writes */
544 	int			l_prev_cycle;   /* Cycle number before last
545 						 * block increment */
546 	int			l_curr_block;   /* current logical log block */
547 	int			l_prev_block;   /* previous logical log block */
548 	int			l_iclog_size;	/* size of log in bytes */
549 	int			l_iclog_size_log; /* log power size of log */
550 	int			l_iclog_bufs;	/* number of iclog buffers */
551 
552 	/* The following field are used for debugging; need to hold icloglock */
553 	char			*l_iclog_bak[XLOG_MAX_ICLOGS];
554 
555 	/* The following block of fields are changed while holding grant_lock */
556 	lock_t			l_grant_lock;
557 	xlog_ticket_t		*l_reserve_headq;
558 	xlog_ticket_t		*l_write_headq;
559 	int			l_grant_reserve_cycle;
560 	int			l_grant_reserve_bytes;
561 	int			l_grant_write_cycle;
562 	int			l_grant_write_bytes;
563 
564 	/* The following fields don't need locking */
565 #ifdef XFS_LOG_TRACE
566 	struct ktrace		*l_trace;
567 	struct ktrace		*l_grant_trace;
568 #endif
569 	uint			l_flags;
570 	uint			l_quotaoffs_flag; /* XFS_DQ_*, for QUOTAOFFs */
571 	struct xfs_buf_cancel	**l_buf_cancel_table;
572 	int			l_iclog_hsize;  /* size of iclog header */
573 	int			l_iclog_heads;  /* # of iclog header sectors */
574 	uint			l_sectbb_log;   /* log2 of sector size in BBs */
575 	uint			l_sectbb_mask;  /* sector size (in BBs)
576 						 * alignment mask */
577 } xlog_t;
578 
579 
580 /* common routines */
581 extern xfs_lsn_t xlog_assign_tail_lsn(struct xfs_mount *mp);
582 extern int	 xlog_find_tail(xlog_t	*log,
583 				xfs_daddr_t *head_blk,
584 				xfs_daddr_t *tail_blk,
585 				int readonly);
586 extern int	 xlog_recover(xlog_t *log, int readonly);
587 extern int	 xlog_recover_finish(xlog_t *log, int mfsi_flags);
588 extern void	 xlog_pack_data(xlog_t *log, xlog_in_core_t *iclog, int);
589 extern void	 xlog_recover_process_iunlinks(xlog_t *log);
590 
591 extern struct xfs_buf *xlog_get_bp(xlog_t *, int);
592 extern void	 xlog_put_bp(struct xfs_buf *);
593 extern int	 xlog_bread(xlog_t *, xfs_daddr_t, int, struct xfs_buf *);
594 
595 /* iclog tracing */
596 #define XLOG_TRACE_GRAB_FLUSH  1
597 #define XLOG_TRACE_REL_FLUSH   2
598 #define XLOG_TRACE_SLEEP_FLUSH 3
599 #define XLOG_TRACE_WAKE_FLUSH  4
600 
601 #endif	/* __KERNEL__ */
602 
603 #endif	/* __XFS_LOG_PRIV_H__ */
604