1/*
  2 * Copyright (C) 2016 Oracle.  All Rights Reserved.
  3 *
  4 * Author: Darrick J. Wong <darrick.wong@oracle.com>
  5 *
  6 * This program is free software; you can redistribute it and/or
  7 * modify it under the terms of the GNU General Public License
  8 * as published by the Free Software Foundation; either version 2
  9 * of the License, or (at your option) any later version.
 10 *
 11 * This program is distributed in the hope that it would be useful,
 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 14 * GNU General Public License for more details.
 15 *
 16 * You should have received a copy of the GNU General Public License
 17 * along with this program; if not, write the Free Software Foundation,
 18 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301, USA.
 19 */
 20#include "xfs.h"
 21#include "xfs_fs.h"
 22#include "xfs_format.h"
 23#include "xfs_log_format.h"
 24#include "xfs_trans_resv.h"
 25#include "xfs_bit.h"
 26#include "xfs_shared.h"
 27#include "xfs_mount.h"
 28#include "xfs_defer.h"
 29#include "xfs_trans.h"
 30#include "xfs_trans_priv.h"
 31#include "xfs_buf_item.h"
 32#include "xfs_refcount_item.h"
 33#include "xfs_log.h"
 34#include "xfs_refcount.h"
 35
 36
 37kmem_zone_t	*xfs_cui_zone;
 38kmem_zone_t	*xfs_cud_zone;
 39
 40static inline struct xfs_cui_log_item *CUI_ITEM(struct xfs_log_item *lip)
 41{
 42	return container_of(lip, struct xfs_cui_log_item, cui_item);
 43}
 44
 45void
 46xfs_cui_item_free(
 47	struct xfs_cui_log_item	*cuip)
 48{
 49	if (cuip->cui_format.cui_nextents > XFS_CUI_MAX_FAST_EXTENTS)
 50		kmem_free(cuip);
 51	else
 52		kmem_zone_free(xfs_cui_zone, cuip);
 53}
 54
 55/*
 56 * Freeing the CUI requires that we remove it from the AIL if it has already
 57 * been placed there. However, the CUI may not yet have been placed in the AIL
 58 * when called by xfs_cui_release() from CUD processing due to the ordering of
 59 * committed vs unpin operations in bulk insert operations. Hence the reference
 60 * count to ensure only the last caller frees the CUI.
 61 */
 62void
 63xfs_cui_release(
 64	struct xfs_cui_log_item	*cuip)
 65{
 66	ASSERT(atomic_read(&cuip->cui_refcount) > 0);
 67	if (atomic_dec_and_test(&cuip->cui_refcount)) {
 68		xfs_trans_ail_remove(&cuip->cui_item, SHUTDOWN_LOG_IO_ERROR);
 69		xfs_cui_item_free(cuip);
 70	}
 71}
 72
 73
 74STATIC void
 75xfs_cui_item_size(
 76	struct xfs_log_item	*lip,
 77	int			*nvecs,
 78	int			*nbytes)
 79{
 80	struct xfs_cui_log_item	*cuip = CUI_ITEM(lip);
 81
 82	*nvecs += 1;
 83	*nbytes += xfs_cui_log_format_sizeof(cuip->cui_format.cui_nextents);
 84}
 85
 86/*
 87 * This is called to fill in the vector of log iovecs for the
 88 * given cui log item. We use only 1 iovec, and we point that
 89 * at the cui_log_format structure embedded in the cui item.
 90 * It is at this point that we assert that all of the extent
 91 * slots in the cui item have been filled.
 92 */
 93STATIC void
 94xfs_cui_item_format(
 95	struct xfs_log_item	*lip,
 96	struct xfs_log_vec	*lv)
 97{
 98	struct xfs_cui_log_item	*cuip = CUI_ITEM(lip);
 99	struct xfs_log_iovec	*vecp = NULL;
100
101	ASSERT(atomic_read(&cuip->cui_next_extent) ==
102			cuip->cui_format.cui_nextents);
103
104	cuip->cui_format.cui_type = XFS_LI_CUI;
105	cuip->cui_format.cui_size = 1;
106
107	xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_CUI_FORMAT, &cuip->cui_format,
108			xfs_cui_log_format_sizeof(cuip->cui_format.cui_nextents));
109}
110
111/*
112 * Pinning has no meaning for an cui item, so just return.
113 */
114STATIC void
115xfs_cui_item_pin(
116	struct xfs_log_item	*lip)
117{
118}
119
120/*
121 * The unpin operation is the last place an CUI is manipulated in the log. It is
122 * either inserted in the AIL or aborted in the event of a log I/O error. In
123 * either case, the CUI transaction has been successfully committed to make it
124 * this far. Therefore, we expect whoever committed the CUI to either construct
125 * and commit the CUD or drop the CUD's reference in the event of error. Simply
126 * drop the log's CUI reference now that the log is done with it.
127 */
128STATIC void
129xfs_cui_item_unpin(
130	struct xfs_log_item	*lip,
131	int			remove)
132{
133	struct xfs_cui_log_item	*cuip = CUI_ITEM(lip);
134
135	xfs_cui_release(cuip);
136}
137
138/*
139 * CUI items have no locking or pushing.  However, since CUIs are pulled from
140 * the AIL when their corresponding CUDs are committed to disk, their situation
141 * is very similar to being pinned.  Return XFS_ITEM_PINNED so that the caller
142 * will eventually flush the log.  This should help in getting the CUI out of
143 * the AIL.
144 */
145STATIC uint
146xfs_cui_item_push(
147	struct xfs_log_item	*lip,
148	struct list_head	*buffer_list)
149{
150	return XFS_ITEM_PINNED;
151}
152
153/*
154 * The CUI has been either committed or aborted if the transaction has been
155 * cancelled. If the transaction was cancelled, an CUD isn't going to be
156 * constructed and thus we free the CUI here directly.
157 */
158STATIC void
159xfs_cui_item_unlock(
160	struct xfs_log_item	*lip)
161{
162	if (lip->li_flags & XFS_LI_ABORTED)
163		xfs_cui_release(CUI_ITEM(lip));
164}
165
166/*
167 * The CUI is logged only once and cannot be moved in the log, so simply return
168 * the lsn at which it's been logged.
169 */
170STATIC xfs_lsn_t
171xfs_cui_item_committed(
172	struct xfs_log_item	*lip,
173	xfs_lsn_t		lsn)
174{
175	return lsn;
176}
177
178/*
179 * The CUI dependency tracking op doesn't do squat.  It can't because
180 * it doesn't know where the free extent is coming from.  The dependency
181 * tracking has to be handled by the "enclosing" metadata object.  For
182 * example, for inodes, the inode is locked throughout the extent freeing
183 * so the dependency should be recorded there.
184 */
185STATIC void
186xfs_cui_item_committing(
187	struct xfs_log_item	*lip,
188	xfs_lsn_t		lsn)
189{
190}
191
192/*
193 * This is the ops vector shared by all cui log items.
194 */
195static const struct xfs_item_ops xfs_cui_item_ops = {
196	.iop_size	= xfs_cui_item_size,
197	.iop_format	= xfs_cui_item_format,
198	.iop_pin	= xfs_cui_item_pin,
199	.iop_unpin	= xfs_cui_item_unpin,
200	.iop_unlock	= xfs_cui_item_unlock,
201	.iop_committed	= xfs_cui_item_committed,
202	.iop_push	= xfs_cui_item_push,
203	.iop_committing = xfs_cui_item_committing,
204};
205
206/*
207 * Allocate and initialize an cui item with the given number of extents.
208 */
209struct xfs_cui_log_item *
210xfs_cui_init(
211	struct xfs_mount		*mp,
212	uint				nextents)
213
214{
215	struct xfs_cui_log_item		*cuip;
216
217	ASSERT(nextents > 0);
218	if (nextents > XFS_CUI_MAX_FAST_EXTENTS)
219		cuip = kmem_zalloc(xfs_cui_log_item_sizeof(nextents),
220				KM_SLEEP);
221	else
222		cuip = kmem_zone_zalloc(xfs_cui_zone, KM_SLEEP);
223
224	xfs_log_item_init(mp, &cuip->cui_item, XFS_LI_CUI, &xfs_cui_item_ops);
225	cuip->cui_format.cui_nextents = nextents;
226	cuip->cui_format.cui_id = (uintptr_t)(void *)cuip;
227	atomic_set(&cuip->cui_next_extent, 0);
228	atomic_set(&cuip->cui_refcount, 2);
229
230	return cuip;
231}
232
233static inline struct xfs_cud_log_item *CUD_ITEM(struct xfs_log_item *lip)
234{
235	return container_of(lip, struct xfs_cud_log_item, cud_item);
236}
237
238STATIC void
239xfs_cud_item_size(
240	struct xfs_log_item	*lip,
241	int			*nvecs,
242	int			*nbytes)
243{
244	*nvecs += 1;
245	*nbytes += sizeof(struct xfs_cud_log_format);
246}
247
248/*
249 * This is called to fill in the vector of log iovecs for the
250 * given cud log item. We use only 1 iovec, and we point that
251 * at the cud_log_format structure embedded in the cud item.
252 * It is at this point that we assert that all of the extent
253 * slots in the cud item have been filled.
254 */
255STATIC void
256xfs_cud_item_format(
257	struct xfs_log_item	*lip,
258	struct xfs_log_vec	*lv)
259{
260	struct xfs_cud_log_item	*cudp = CUD_ITEM(lip);
261	struct xfs_log_iovec	*vecp = NULL;
262
263	cudp->cud_format.cud_type = XFS_LI_CUD;
264	cudp->cud_format.cud_size = 1;
265
266	xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_CUD_FORMAT, &cudp->cud_format,
267			sizeof(struct xfs_cud_log_format));
268}
269
270/*
271 * Pinning has no meaning for an cud item, so just return.
272 */
273STATIC void
274xfs_cud_item_pin(
275	struct xfs_log_item	*lip)
276{
277}
278
279/*
280 * Since pinning has no meaning for an cud item, unpinning does
281 * not either.
282 */
283STATIC void
284xfs_cud_item_unpin(
285	struct xfs_log_item	*lip,
286	int			remove)
287{
288}
289
290/*
291 * There isn't much you can do to push on an cud item.  It is simply stuck
292 * waiting for the log to be flushed to disk.
293 */
294STATIC uint
295xfs_cud_item_push(
296	struct xfs_log_item	*lip,
297	struct list_head	*buffer_list)
298{
299	return XFS_ITEM_PINNED;
300}
301
302/*
303 * The CUD is either committed or aborted if the transaction is cancelled. If
304 * the transaction is cancelled, drop our reference to the CUI and free the
305 * CUD.
306 */
307STATIC void
308xfs_cud_item_unlock(
309	struct xfs_log_item	*lip)
310{
311	struct xfs_cud_log_item	*cudp = CUD_ITEM(lip);
312
313	if (lip->li_flags & XFS_LI_ABORTED) {
314		xfs_cui_release(cudp->cud_cuip);
315		kmem_zone_free(xfs_cud_zone, cudp);
316	}
317}
318
319/*
320 * When the cud item is committed to disk, all we need to do is delete our
321 * reference to our partner cui item and then free ourselves. Since we're
322 * freeing ourselves we must return -1 to keep the transaction code from
323 * further referencing this item.
324 */
325STATIC xfs_lsn_t
326xfs_cud_item_committed(
327	struct xfs_log_item	*lip,
328	xfs_lsn_t		lsn)
329{
330	struct xfs_cud_log_item	*cudp = CUD_ITEM(lip);
331
332	/*
333	 * Drop the CUI reference regardless of whether the CUD has been
334	 * aborted. Once the CUD transaction is constructed, it is the sole
335	 * responsibility of the CUD to release the CUI (even if the CUI is
336	 * aborted due to log I/O error).
337	 */
338	xfs_cui_release(cudp->cud_cuip);
339	kmem_zone_free(xfs_cud_zone, cudp);
340
341	return (xfs_lsn_t)-1;
342}
343
344/*
345 * The CUD dependency tracking op doesn't do squat.  It can't because
346 * it doesn't know where the free extent is coming from.  The dependency
347 * tracking has to be handled by the "enclosing" metadata object.  For
348 * example, for inodes, the inode is locked throughout the extent freeing
349 * so the dependency should be recorded there.
350 */
351STATIC void
352xfs_cud_item_committing(
353	struct xfs_log_item	*lip,
354	xfs_lsn_t		lsn)
355{
356}
357
358/*
359 * This is the ops vector shared by all cud log items.
360 */
361static const struct xfs_item_ops xfs_cud_item_ops = {
362	.iop_size	= xfs_cud_item_size,
363	.iop_format	= xfs_cud_item_format,
364	.iop_pin	= xfs_cud_item_pin,
365	.iop_unpin	= xfs_cud_item_unpin,
366	.iop_unlock	= xfs_cud_item_unlock,
367	.iop_committed	= xfs_cud_item_committed,
368	.iop_push	= xfs_cud_item_push,
369	.iop_committing = xfs_cud_item_committing,
370};
371
372/*
373 * Allocate and initialize an cud item with the given number of extents.
374 */
375struct xfs_cud_log_item *
376xfs_cud_init(
377	struct xfs_mount		*mp,
378	struct xfs_cui_log_item		*cuip)
379
380{
381	struct xfs_cud_log_item	*cudp;
382
383	cudp = kmem_zone_zalloc(xfs_cud_zone, KM_SLEEP);
384	xfs_log_item_init(mp, &cudp->cud_item, XFS_LI_CUD, &xfs_cud_item_ops);
385	cudp->cud_cuip = cuip;
386	cudp->cud_format.cud_cui_id = cuip->cui_format.cui_id;
387
388	return cudp;
389}
390
391/*
392 * Process a refcount update intent item that was recovered from the log.
393 * We need to update the refcountbt.
394 */
395int
396xfs_cui_recover(
397	struct xfs_mount		*mp,
398	struct xfs_cui_log_item		*cuip,
399	struct xfs_defer_ops		*dfops)
400{
401	int				i;
402	int				error = 0;
403	unsigned int			refc_type;
404	struct xfs_phys_extent		*refc;
405	xfs_fsblock_t			startblock_fsb;
406	bool				op_ok;
407	struct xfs_cud_log_item		*cudp;
408	struct xfs_trans		*tp;
409	struct xfs_btree_cur		*rcur = NULL;
410	enum xfs_refcount_intent_type	type;
411	xfs_fsblock_t			new_fsb;
412	xfs_extlen_t			new_len;
413	struct xfs_bmbt_irec		irec;
414	bool				requeue_only = false;
415
416	ASSERT(!test_bit(XFS_CUI_RECOVERED, &cuip->cui_flags));
417
418	/*
419	 * First check the validity of the extents described by the
420	 * CUI.  If any are bad, then assume that all are bad and
421	 * just toss the CUI.
422	 */
423	for (i = 0; i < cuip->cui_format.cui_nextents; i++) {
424		refc = &cuip->cui_format.cui_extents[i];
425		startblock_fsb = XFS_BB_TO_FSB(mp,
426				   XFS_FSB_TO_DADDR(mp, refc->pe_startblock));
427		switch (refc->pe_flags & XFS_REFCOUNT_EXTENT_TYPE_MASK) {
428		case XFS_REFCOUNT_INCREASE:
429		case XFS_REFCOUNT_DECREASE:
430		case XFS_REFCOUNT_ALLOC_COW:
431		case XFS_REFCOUNT_FREE_COW:
432			op_ok = true;
433			break;
434		default:
435			op_ok = false;
436			break;
437		}
438		if (!op_ok || startblock_fsb == 0 ||
439		    refc->pe_len == 0 ||
440		    startblock_fsb >= mp->m_sb.sb_dblocks ||
441		    refc->pe_len >= mp->m_sb.sb_agblocks ||
442		    (refc->pe_flags & ~XFS_REFCOUNT_EXTENT_FLAGS)) {
443			/*
444			 * This will pull the CUI from the AIL and
445			 * free the memory associated with it.
446			 */
447			set_bit(XFS_CUI_RECOVERED, &cuip->cui_flags);
448			xfs_cui_release(cuip);
449			return -EIO;
450		}
451	}
452
453	/*
454	 * Under normal operation, refcount updates are deferred, so we
455	 * wouldn't be adding them directly to a transaction.  All
456	 * refcount updates manage reservation usage internally and
457	 * dynamically by deferring work that won't fit in the
458	 * transaction.  Normally, any work that needs to be deferred
459	 * gets attached to the same defer_ops that scheduled the
460	 * refcount update.  However, we're in log recovery here, so we
461	 * we use the passed in defer_ops and to finish up any work that
462	 * doesn't fit.  We need to reserve enough blocks to handle a
463	 * full btree split on either end of the refcount range.
464	 */
465	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate,
466			mp->m_refc_maxlevels * 2, 0, XFS_TRANS_RESERVE, &tp);
467	if (error)
468		return error;
469	cudp = xfs_trans_get_cud(tp, cuip);
470
471	for (i = 0; i < cuip->cui_format.cui_nextents; i++) {
472		refc = &cuip->cui_format.cui_extents[i];
473		refc_type = refc->pe_flags & XFS_REFCOUNT_EXTENT_TYPE_MASK;
474		switch (refc_type) {
475		case XFS_REFCOUNT_INCREASE:
476		case XFS_REFCOUNT_DECREASE:
477		case XFS_REFCOUNT_ALLOC_COW:
478		case XFS_REFCOUNT_FREE_COW:
479			type = refc_type;
480			break;
481		default:
482			error = -EFSCORRUPTED;
483			goto abort_error;
484		}
485		if (requeue_only) {
486			new_fsb = refc->pe_startblock;
487			new_len = refc->pe_len;
488		} else
489			error = xfs_trans_log_finish_refcount_update(tp, cudp,
490				dfops, type, refc->pe_startblock, refc->pe_len,
491				&new_fsb, &new_len, &rcur);
492		if (error)
493			goto abort_error;
494
495		/* Requeue what we didn't finish. */
496		if (new_len > 0) {
497			irec.br_startblock = new_fsb;
498			irec.br_blockcount = new_len;
499			switch (type) {
500			case XFS_REFCOUNT_INCREASE:
501				error = xfs_refcount_increase_extent(
502						tp->t_mountp, dfops, &irec);
503				break;
504			case XFS_REFCOUNT_DECREASE:
505				error = xfs_refcount_decrease_extent(
506						tp->t_mountp, dfops, &irec);
507				break;
508			case XFS_REFCOUNT_ALLOC_COW:
509				error = xfs_refcount_alloc_cow_extent(
510						tp->t_mountp, dfops,
511						irec.br_startblock,
512						irec.br_blockcount);
513				break;
514			case XFS_REFCOUNT_FREE_COW:
515				error = xfs_refcount_free_cow_extent(
516						tp->t_mountp, dfops,
517						irec.br_startblock,
518						irec.br_blockcount);
519				break;
520			default:
521				ASSERT(0);
522			}
523			if (error)
524				goto abort_error;
525			requeue_only = true;
526		}
527	}
528
529	xfs_refcount_finish_one_cleanup(tp, rcur, error);
530	set_bit(XFS_CUI_RECOVERED, &cuip->cui_flags);
531	error = xfs_trans_commit(tp);
532	return error;
533
534abort_error:
535	xfs_refcount_finish_one_cleanup(tp, rcur, error);
536	xfs_trans_cancel(tp);
537	return error;
538}