aboutsummaryrefslogblamecommitdiffstats
path: root/fs/xfs/xfs_trans_item.c
blob: 486147ef0e3d5dcac58d467476cd2fb2d3edf531 (plain) (tree)
1
2
3
4
5
6
7
8
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
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
  

                                                      
  

                                                                 

                                             



                                                                   
  


                                                                       
   
                
                   
                      
                    
                     



































































































































































































































































































































































































































































































































                                                                                  
/*
 * Copyright (c) 2000-2002,2005 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
 */
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_types.h"
#include "xfs_log.h"
#include "xfs_inum.h"
#include "xfs_trans.h"

STATIC int	xfs_trans_unlock_chunk(xfs_log_item_chunk_t *,
					int, int, xfs_lsn_t);

/*
 * This is called to add the given log item to the transaction's
 * list of log items.  It must find a free log item descriptor
 * or allocate a new one and add the item to that descriptor.
 * The function returns a pointer to item descriptor used to point
 * to the new item.  The log item will now point to its new descriptor
 * with its li_desc field.
 */
xfs_log_item_desc_t *
xfs_trans_add_item(xfs_trans_t *tp, xfs_log_item_t *lip)
{
	xfs_log_item_desc_t	*lidp;
	xfs_log_item_chunk_t	*licp;
	int			i=0;

	/*
	 * If there are no free descriptors, allocate a new chunk
	 * of them and put it at the front of the chunk list.
	 */
	if (tp->t_items_free == 0) {
		licp = (xfs_log_item_chunk_t*)
		       kmem_alloc(sizeof(xfs_log_item_chunk_t), KM_SLEEP);
		ASSERT(licp != NULL);
		/*
		 * Initialize the chunk, and then
		 * claim the first slot in the newly allocated chunk.
		 */
		XFS_LIC_INIT(licp);
		XFS_LIC_CLAIM(licp, 0);
		licp->lic_unused = 1;
		XFS_LIC_INIT_SLOT(licp, 0);
		lidp = XFS_LIC_SLOT(licp, 0);

		/*
		 * Link in the new chunk and update the free count.
		 */
		licp->lic_next = tp->t_items.lic_next;
		tp->t_items.lic_next = licp;
		tp->t_items_free = XFS_LIC_NUM_SLOTS - 1;

		/*
		 * Initialize the descriptor and the generic portion
		 * of the log item.
		 *
		 * Point the new slot at this item and return it.
		 * Also point the log item at its currently active
		 * descriptor and set the item's mount pointer.
		 */
		lidp->lid_item = lip;
		lidp->lid_flags = 0;
		lidp->lid_size = 0;
		lip->li_desc = lidp;
		lip->li_mountp = tp->t_mountp;
		return (lidp);
	}

	/*
	 * Find the free descriptor. It is somewhere in the chunklist
	 * of descriptors.
	 */
	licp = &tp->t_items;
	while (licp != NULL) {
		if (XFS_LIC_VACANCY(licp)) {
			if (licp->lic_unused <= XFS_LIC_MAX_SLOT) {
				i = licp->lic_unused;
				ASSERT(XFS_LIC_ISFREE(licp, i));
				break;
			}
			for (i = 0; i <= XFS_LIC_MAX_SLOT; i++) {
				if (XFS_LIC_ISFREE(licp, i))
					break;
			}
			ASSERT(i <= XFS_LIC_MAX_SLOT);
			break;
		}
		licp = licp->lic_next;
	}
	ASSERT(licp != NULL);
	/*
	 * If we find a free descriptor, claim it,
	 * initialize it, and return it.
	 */
	XFS_LIC_CLAIM(licp, i);
	if (licp->lic_unused <= i) {
		licp->lic_unused = i + 1;
		XFS_LIC_INIT_SLOT(licp, i);
	}
	lidp = XFS_LIC_SLOT(licp, i);
	tp->t_items_free--;
	lidp->lid_item = lip;
	lidp->lid_flags = 0;
	lidp->lid_size = 0;
	lip->li_desc = lidp;
	lip->li_mountp = tp->t_mountp;
	return (lidp);
}

/*
 * Free the given descriptor.
 *
 * This requires setting the bit in the chunk's free mask corresponding
 * to the given slot.
 */
void
xfs_trans_free_item(xfs_trans_t	*tp, xfs_log_item_desc_t *lidp)
{
	uint			slot;
	xfs_log_item_chunk_t	*licp;
	xfs_log_item_chunk_t	**licpp;

	slot = XFS_LIC_DESC_TO_SLOT(lidp);
	licp = XFS_LIC_DESC_TO_CHUNK(lidp);
	XFS_LIC_RELSE(licp, slot);
	lidp->lid_item->li_desc = NULL;
	tp->t_items_free++;

	/*
	 * If there are no more used items in the chunk and this is not
	 * the chunk embedded in the transaction structure, then free
	 * the chunk. First pull it from the chunk list and then
	 * free it back to the heap.  We didn't bother with a doubly
	 * linked list here because the lists should be very short
	 * and this is not a performance path.  It's better to save
	 * the memory of the extra pointer.
	 *
	 * Also decrement the transaction structure's count of free items
	 * by the number in a chunk since we are freeing an empty chunk.
	 */
	if (XFS_LIC_ARE_ALL_FREE(licp) && (licp != &(tp->t_items))) {
		licpp = &(tp->t_items.lic_next);
		while (*licpp != licp) {
			ASSERT(*licpp != NULL);
			licpp = &((*licpp)->lic_next);
		}
		*licpp = licp->lic_next;
		kmem_free(licp, sizeof(xfs_log_item_chunk_t));
		tp->t_items_free -= XFS_LIC_NUM_SLOTS;
	}
}

/*
 * This is called to find the descriptor corresponding to the given
 * log item.  It returns a pointer to the descriptor.
 * The log item MUST have a corresponding descriptor in the given
 * transaction.  This routine does not return NULL, it panics.
 *
 * The descriptor pointer is kept in the log item's li_desc field.
 * Just return it.
 */
/*ARGSUSED*/
xfs_log_item_desc_t *
xfs_trans_find_item(xfs_trans_t	*tp, xfs_log_item_t *lip)
{
	ASSERT(lip->li_desc != NULL);

	return (lip->li_desc);
}


/*
 * Return a pointer to the first descriptor in the chunk list.
 * This does not return NULL if there are none, it panics.
 *
 * The first descriptor must be in either the first or second chunk.
 * This is because the only chunk allowed to be empty is the first.
 * All others are freed when they become empty.
 *
 * At some point this and xfs_trans_next_item() should be optimized
 * to quickly look at the mask to determine if there is anything to
 * look at.
 */
xfs_log_item_desc_t *
xfs_trans_first_item(xfs_trans_t *tp)
{
	xfs_log_item_chunk_t	*licp;
	int			i;

	licp = &tp->t_items;
	/*
	 * If it's not in the first chunk, skip to the second.
	 */
	if (XFS_LIC_ARE_ALL_FREE(licp)) {
		licp = licp->lic_next;
	}

	/*
	 * Return the first non-free descriptor in the chunk.
	 */
	ASSERT(!XFS_LIC_ARE_ALL_FREE(licp));
	for (i = 0; i < licp->lic_unused; i++) {
		if (XFS_LIC_ISFREE(licp, i)) {
			continue;
		}

		return (XFS_LIC_SLOT(licp, i));
	}
	cmn_err(CE_WARN, "xfs_trans_first_item() -- no first item");
	return(NULL);
}


/*
 * Given a descriptor, return the next descriptor in the chunk list.
 * This returns NULL if there are no more used descriptors in the list.
 *
 * We do this by first locating the chunk in which the descriptor resides,
 * and then scanning forward in the chunk and the list for the next
 * used descriptor.
 */
/*ARGSUSED*/
xfs_log_item_desc_t *
xfs_trans_next_item(xfs_trans_t *tp, xfs_log_item_desc_t *lidp)
{
	xfs_log_item_chunk_t	*licp;
	int			i;

	licp = XFS_LIC_DESC_TO_CHUNK(lidp);

	/*
	 * First search the rest of the chunk. The for loop keeps us
	 * from referencing things beyond the end of the chunk.
	 */
	for (i = (int)XFS_LIC_DESC_TO_SLOT(lidp) + 1; i < licp->lic_unused; i++) {
		if (XFS_LIC_ISFREE(licp, i)) {
			continue;
		}

		return (XFS_LIC_SLOT(licp, i));
	}

	/*
	 * Now search the next chunk.  It must be there, because the
	 * next chunk would have been freed if it were empty.
	 * If there is no next chunk, return NULL.
	 */
	if (licp->lic_next == NULL) {
		return (NULL);
	}

	licp = licp->lic_next;
	ASSERT(!XFS_LIC_ARE_ALL_FREE(licp));
	for (i = 0; i < licp->lic_unused; i++) {
		if (XFS_LIC_ISFREE(licp, i)) {
			continue;
		}

		return (XFS_LIC_SLOT(licp, i));
	}
	ASSERT(0);
	/* NOTREACHED */
	return NULL; /* keep gcc quite */
}

/*
 * This is called to unlock all of the items of a transaction and to free
 * all the descriptors of that transaction.
 *
 * It walks the list of descriptors and unlocks each item.  It frees
 * each chunk except that embedded in the transaction as it goes along.
 */
void
xfs_trans_free_items(
	xfs_trans_t	*tp,
	int		flags)
{
	xfs_log_item_chunk_t	*licp;
	xfs_log_item_chunk_t	*next_licp;
	int			abort;

	abort = flags & XFS_TRANS_ABORT;
	licp = &tp->t_items;
	/*
	 * Special case the embedded chunk so we don't free it below.
	 */
	if (!XFS_LIC_ARE_ALL_FREE(licp)) {
		(void) xfs_trans_unlock_chunk(licp, 1, abort, NULLCOMMITLSN);
		XFS_LIC_ALL_FREE(licp);
		licp->lic_unused = 0;
	}
	licp = licp->lic_next;

	/*
	 * Unlock each item in each chunk and free the chunks.
	 */
	while (licp != NULL) {
		ASSERT(!XFS_LIC_ARE_ALL_FREE(licp));
		(void) xfs_trans_unlock_chunk(licp, 1, abort, NULLCOMMITLSN);
		next_licp = licp->lic_next;
		kmem_free(licp, sizeof(xfs_log_item_chunk_t));
		licp = next_licp;
	}

	/*
	 * Reset the transaction structure's free item count.
	 */
	tp->t_items_free = XFS_LIC_NUM_SLOTS;
	tp->t_items.lic_next = NULL;
}



/*
 * This is called to unlock the items associated with a transaction.
 * Items which were not logged should be freed.
 * Those which were logged must still be tracked so they can be unpinned
 * when the transaction commits.
 */
void
xfs_trans_unlock_items(xfs_trans_t *tp, xfs_lsn_t commit_lsn)
{
	xfs_log_item_chunk_t	*licp;
	xfs_log_item_chunk_t	*next_licp;
	xfs_log_item_chunk_t	**licpp;
	int			freed;

	freed = 0;
	licp = &tp->t_items;

	/*
	 * Special case the embedded chunk so we don't free.
	 */
	if (!XFS_LIC_ARE_ALL_FREE(licp)) {
		freed = xfs_trans_unlock_chunk(licp, 0, 0, commit_lsn);
	}
	licpp = &(tp->t_items.lic_next);
	licp = licp->lic_next;

	/*
	 * Unlock each item in each chunk, free non-dirty descriptors,
	 * and free empty chunks.
	 */
	while (licp != NULL) {
		ASSERT(!XFS_LIC_ARE_ALL_FREE(licp));
		freed += xfs_trans_unlock_chunk(licp, 0, 0, commit_lsn);
		next_licp = licp->lic_next;
		if (XFS_LIC_ARE_ALL_FREE(licp)) {
			*licpp = next_licp;
			kmem_free(licp, sizeof(xfs_log_item_chunk_t));
			freed -= XFS_LIC_NUM_SLOTS;
		} else {
			licpp = &(licp->lic_next);
		}
		ASSERT(*licpp == next_licp);
		licp = next_licp;
	}

	/*
	 * Fix the free descriptor count in the transaction.
	 */
	tp->t_items_free += freed;
}

/*
 * Unlock each item pointed to by a descriptor in the given chunk.
 * Stamp the commit lsn into each item if necessary.
 * Free descriptors pointing to items which are not dirty if freeing_chunk
 * is zero. If freeing_chunk is non-zero, then we need to unlock all
 * items in the chunk.
 * 
 * Return the number of descriptors freed.
 */
STATIC int
xfs_trans_unlock_chunk(
	xfs_log_item_chunk_t	*licp,
	int			freeing_chunk,
	int			abort,
	xfs_lsn_t		commit_lsn)
{
	xfs_log_item_desc_t	*lidp;
	xfs_log_item_t		*lip;
	int			i;
	int			freed;

	freed = 0;
	lidp = licp->lic_descs;
	for (i = 0; i < licp->lic_unused; i++, lidp++) {
		if (XFS_LIC_ISFREE(licp, i)) {
			continue;
		}
		lip = lidp->lid_item;
		lip->li_desc = NULL;

		if (commit_lsn != NULLCOMMITLSN)
			IOP_COMMITTING(lip, commit_lsn);
		if (abort)
			lip->li_flags |= XFS_LI_ABORTED;
		IOP_UNLOCK(lip);

		/*
		 * Free the descriptor if the item is not dirty
		 * within this transaction and the caller is not
		 * going to just free the entire thing regardless.
		 */
		if (!(freeing_chunk) &&
		    (!(lidp->lid_flags & XFS_LID_DIRTY) || abort)) {
			XFS_LIC_RELSE(licp, i);
			freed++;
		}
	}

	return (freed);
}


/*
 * This is called to add the given busy item to the transaction's
 * list of busy items.  It must find a free busy item descriptor
 * or allocate a new one and add the item to that descriptor.
 * The function returns a pointer to busy descriptor used to point
 * to the new busy entry.  The log busy entry will now point to its new
 * descriptor with its ???? field.
 */
xfs_log_busy_slot_t *
xfs_trans_add_busy(xfs_trans_t *tp, xfs_agnumber_t ag, xfs_extlen_t idx)
{
	xfs_log_busy_chunk_t	*lbcp;
	xfs_log_busy_slot_t	*lbsp;
	int			i=0;

	/*
	 * If there are no free descriptors, allocate a new chunk
	 * of them and put it at the front of the chunk list.
	 */
	if (tp->t_busy_free == 0) {
		lbcp = (xfs_log_busy_chunk_t*)
		       kmem_alloc(sizeof(xfs_log_busy_chunk_t), KM_SLEEP);
		ASSERT(lbcp != NULL);
		/*
		 * Initialize the chunk, and then
		 * claim the first slot in the newly allocated chunk.
		 */
		XFS_LBC_INIT(lbcp);
		XFS_LBC_CLAIM(lbcp, 0);
		lbcp->lbc_unused = 1;
		lbsp = XFS_LBC_SLOT(lbcp, 0);

		/*
		 * Link in the new chunk and update the free count.
		 */
		lbcp->lbc_next = tp->t_busy.lbc_next;
		tp->t_busy.lbc_next = lbcp;
		tp->t_busy_free = XFS_LIC_NUM_SLOTS - 1;

		/*
		 * Initialize the descriptor and the generic portion
		 * of the log item.
		 *
		 * Point the new slot at this item and return it.
		 * Also point the log item at its currently active
		 * descriptor and set the item's mount pointer.
		 */
		lbsp->lbc_ag = ag;
		lbsp->lbc_idx = idx;
		return (lbsp);
	}

	/*
	 * Find the free descriptor. It is somewhere in the chunklist
	 * of descriptors.
	 */
	lbcp = &tp->t_busy;
	while (lbcp != NULL) {
		if (XFS_LBC_VACANCY(lbcp)) {
			if (lbcp->lbc_unused <= XFS_LBC_MAX_SLOT) {
				i = lbcp->lbc_unused;
				break;
			} else {
				/* out-of-order vacancy */
				printk("OOO vacancy lbcp 0x%p\n", lbcp);
				ASSERT(0);
			}
		}
		lbcp = lbcp->lbc_next;
	}
	ASSERT(lbcp != NULL);
	/*
	 * If we find a free descriptor, claim it,
	 * initialize it, and return it.
	 */
	XFS_LBC_CLAIM(lbcp, i);
	if (lbcp->lbc_unused <= i) {
		lbcp->lbc_unused = i + 1;
	}
	lbsp = XFS_LBC_SLOT(lbcp, i);
	tp->t_busy_free--;
	lbsp->lbc_ag = ag;
	lbsp->lbc_idx = idx;
	return (lbsp);
}


/*
 * xfs_trans_free_busy
 * Free all of the busy lists from a transaction
 */
void
xfs_trans_free_busy(xfs_trans_t *tp)
{
	xfs_log_busy_chunk_t	*lbcp;
	xfs_log_busy_chunk_t	*lbcq;

	lbcp = tp->t_busy.lbc_next;
	while (lbcp != NULL) {
		lbcq = lbcp->lbc_next;
		kmem_free(lbcp, sizeof(xfs_log_busy_chunk_t));
		lbcp = lbcq;
	}

	XFS_LBC_INIT(&tp->t_busy);
	tp->t_busy.lbc_unused = 0;
}