xref: /linux/fs/xfs/xfs_dquot_item.c (revision 6a61b70b43c9c4cbc7314bf6c8b5ba8b0d6e1e7b)
1 /*
2  * Copyright (c) 2000-2003 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 #include "xfs.h"
19 #include "xfs_fs.h"
20 #include "xfs_format.h"
21 #include "xfs_log_format.h"
22 #include "xfs_trans_resv.h"
23 #include "xfs_mount.h"
24 #include "xfs_inode.h"
25 #include "xfs_quota.h"
26 #include "xfs_error.h"
27 #include "xfs_trans.h"
28 #include "xfs_buf_item.h"
29 #include "xfs_trans_priv.h"
30 #include "xfs_qm.h"
31 #include "xfs_log.h"
32 
33 static inline struct xfs_dq_logitem *DQUOT_ITEM(struct xfs_log_item *lip)
34 {
35 	return container_of(lip, struct xfs_dq_logitem, qli_item);
36 }
37 
38 /*
39  * returns the number of iovecs needed to log the given dquot item.
40  */
41 STATIC void
42 xfs_qm_dquot_logitem_size(
43 	struct xfs_log_item	*lip,
44 	int			*nvecs,
45 	int			*nbytes)
46 {
47 	*nvecs += 2;
48 	*nbytes += sizeof(struct xfs_dq_logformat) +
49 		   sizeof(struct xfs_disk_dquot);
50 }
51 
52 /*
53  * fills in the vector of log iovecs for the given dquot log item.
54  */
55 STATIC void
56 xfs_qm_dquot_logitem_format(
57 	struct xfs_log_item	*lip,
58 	struct xfs_log_vec	*lv)
59 {
60 	struct xfs_dq_logitem	*qlip = DQUOT_ITEM(lip);
61 	struct xfs_log_iovec	*vecp = NULL;
62 	struct xfs_dq_logformat	*qlf;
63 
64 	qlf = xlog_prepare_iovec(lv, &vecp, XLOG_REG_TYPE_QFORMAT);
65 	qlf->qlf_type = XFS_LI_DQUOT;
66 	qlf->qlf_size = 2;
67 	qlf->qlf_id = be32_to_cpu(qlip->qli_dquot->q_core.d_id);
68 	qlf->qlf_blkno = qlip->qli_dquot->q_blkno;
69 	qlf->qlf_len = 1;
70 	qlf->qlf_boffset = qlip->qli_dquot->q_bufoffset;
71 	xlog_finish_iovec(lv, vecp, sizeof(struct xfs_dq_logformat));
72 
73 	xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_DQUOT,
74 			&qlip->qli_dquot->q_core,
75 			sizeof(struct xfs_disk_dquot));
76 }
77 
78 /*
79  * Increment the pin count of the given dquot.
80  */
81 STATIC void
82 xfs_qm_dquot_logitem_pin(
83 	struct xfs_log_item	*lip)
84 {
85 	struct xfs_dquot	*dqp = DQUOT_ITEM(lip)->qli_dquot;
86 
87 	ASSERT(XFS_DQ_IS_LOCKED(dqp));
88 	atomic_inc(&dqp->q_pincount);
89 }
90 
91 /*
92  * Decrement the pin count of the given dquot, and wake up
93  * anyone in xfs_dqwait_unpin() if the count goes to 0.	 The
94  * dquot must have been previously pinned with a call to
95  * xfs_qm_dquot_logitem_pin().
96  */
97 STATIC void
98 xfs_qm_dquot_logitem_unpin(
99 	struct xfs_log_item	*lip,
100 	int			remove)
101 {
102 	struct xfs_dquot	*dqp = DQUOT_ITEM(lip)->qli_dquot;
103 
104 	ASSERT(atomic_read(&dqp->q_pincount) > 0);
105 	if (atomic_dec_and_test(&dqp->q_pincount))
106 		wake_up(&dqp->q_pinwait);
107 }
108 
109 STATIC xfs_lsn_t
110 xfs_qm_dquot_logitem_committed(
111 	struct xfs_log_item	*lip,
112 	xfs_lsn_t		lsn)
113 {
114 	/*
115 	 * We always re-log the entire dquot when it becomes dirty,
116 	 * so, the latest copy _is_ the only one that matters.
117 	 */
118 	return lsn;
119 }
120 
121 /*
122  * This is called to wait for the given dquot to be unpinned.
123  * Most of these pin/unpin routines are plagiarized from inode code.
124  */
125 void
126 xfs_qm_dqunpin_wait(
127 	struct xfs_dquot	*dqp)
128 {
129 	ASSERT(XFS_DQ_IS_LOCKED(dqp));
130 	if (atomic_read(&dqp->q_pincount) == 0)
131 		return;
132 
133 	/*
134 	 * Give the log a push so we don't wait here too long.
135 	 */
136 	xfs_log_force(dqp->q_mount, 0);
137 	wait_event(dqp->q_pinwait, (atomic_read(&dqp->q_pincount) == 0));
138 }
139 
140 /*
141  * Callback used to mark a buffer with XFS_LI_FAILED when items in the buffer
142  * have been failed during writeback
143  *
144  * this informs the AIL that the dquot is already flush locked on the next push,
145  * and acquires a hold on the buffer to ensure that it isn't reclaimed before
146  * dirty data makes it to disk.
147  */
148 STATIC void
149 xfs_dquot_item_error(
150 	struct xfs_log_item	*lip,
151 	struct xfs_buf		*bp)
152 {
153 	ASSERT(!completion_done(&DQUOT_ITEM(lip)->qli_dquot->q_flush));
154 	xfs_set_li_failed(lip, bp);
155 }
156 
157 STATIC uint
158 xfs_qm_dquot_logitem_push(
159 	struct xfs_log_item	*lip,
160 	struct list_head	*buffer_list)
161 		__releases(&lip->li_ailp->ail_lock)
162 		__acquires(&lip->li_ailp->ail_lock)
163 {
164 	struct xfs_dquot	*dqp = DQUOT_ITEM(lip)->qli_dquot;
165 	struct xfs_buf		*bp = lip->li_buf;
166 	uint			rval = XFS_ITEM_SUCCESS;
167 	int			error;
168 
169 	if (atomic_read(&dqp->q_pincount) > 0)
170 		return XFS_ITEM_PINNED;
171 
172 	/*
173 	 * The buffer containing this item failed to be written back
174 	 * previously. Resubmit the buffer for IO
175 	 */
176 	if (test_bit(XFS_LI_FAILED, &lip->li_flags)) {
177 		if (!xfs_buf_trylock(bp))
178 			return XFS_ITEM_LOCKED;
179 
180 		if (!xfs_buf_resubmit_failed_buffers(bp, buffer_list))
181 			rval = XFS_ITEM_FLUSHING;
182 
183 		xfs_buf_unlock(bp);
184 		return rval;
185 	}
186 
187 	if (!xfs_dqlock_nowait(dqp))
188 		return XFS_ITEM_LOCKED;
189 
190 	/*
191 	 * Re-check the pincount now that we stabilized the value by
192 	 * taking the quota lock.
193 	 */
194 	if (atomic_read(&dqp->q_pincount) > 0) {
195 		rval = XFS_ITEM_PINNED;
196 		goto out_unlock;
197 	}
198 
199 	/*
200 	 * Someone else is already flushing the dquot.  Nothing we can do
201 	 * here but wait for the flush to finish and remove the item from
202 	 * the AIL.
203 	 */
204 	if (!xfs_dqflock_nowait(dqp)) {
205 		rval = XFS_ITEM_FLUSHING;
206 		goto out_unlock;
207 	}
208 
209 	spin_unlock(&lip->li_ailp->ail_lock);
210 
211 	error = xfs_qm_dqflush(dqp, &bp);
212 	if (!error) {
213 		if (!xfs_buf_delwri_queue(bp, buffer_list))
214 			rval = XFS_ITEM_FLUSHING;
215 		xfs_buf_relse(bp);
216 	}
217 
218 	spin_lock(&lip->li_ailp->ail_lock);
219 out_unlock:
220 	xfs_dqunlock(dqp);
221 	return rval;
222 }
223 
224 /*
225  * Unlock the dquot associated with the log item.
226  * Clear the fields of the dquot and dquot log item that
227  * are specific to the current transaction.  If the
228  * hold flags is set, do not unlock the dquot.
229  */
230 STATIC void
231 xfs_qm_dquot_logitem_unlock(
232 	struct xfs_log_item	*lip)
233 {
234 	struct xfs_dquot	*dqp = DQUOT_ITEM(lip)->qli_dquot;
235 
236 	ASSERT(XFS_DQ_IS_LOCKED(dqp));
237 
238 	/*
239 	 * Clear the transaction pointer in the dquot
240 	 */
241 	dqp->q_transp = NULL;
242 
243 	/*
244 	 * dquots are never 'held' from getting unlocked at the end of
245 	 * a transaction.  Their locking and unlocking is hidden inside the
246 	 * transaction layer, within trans_commit. Hence, no LI_HOLD flag
247 	 * for the logitem.
248 	 */
249 	xfs_dqunlock(dqp);
250 }
251 
252 /*
253  * this needs to stamp an lsn into the dquot, I think.
254  * rpc's that look at user dquot's would then have to
255  * push on the dependency recorded in the dquot
256  */
257 STATIC void
258 xfs_qm_dquot_logitem_committing(
259 	struct xfs_log_item	*lip,
260 	xfs_lsn_t		lsn)
261 {
262 }
263 
264 /*
265  * This is the ops vector for dquots
266  */
267 static const struct xfs_item_ops xfs_dquot_item_ops = {
268 	.iop_size	= xfs_qm_dquot_logitem_size,
269 	.iop_format	= xfs_qm_dquot_logitem_format,
270 	.iop_pin	= xfs_qm_dquot_logitem_pin,
271 	.iop_unpin	= xfs_qm_dquot_logitem_unpin,
272 	.iop_unlock	= xfs_qm_dquot_logitem_unlock,
273 	.iop_committed	= xfs_qm_dquot_logitem_committed,
274 	.iop_push	= xfs_qm_dquot_logitem_push,
275 	.iop_committing = xfs_qm_dquot_logitem_committing,
276 	.iop_error	= xfs_dquot_item_error
277 };
278 
279 /*
280  * Initialize the dquot log item for a newly allocated dquot.
281  * The dquot isn't locked at this point, but it isn't on any of the lists
282  * either, so we don't care.
283  */
284 void
285 xfs_qm_dquot_logitem_init(
286 	struct xfs_dquot	*dqp)
287 {
288 	struct xfs_dq_logitem	*lp = &dqp->q_logitem;
289 
290 	xfs_log_item_init(dqp->q_mount, &lp->qli_item, XFS_LI_DQUOT,
291 					&xfs_dquot_item_ops);
292 	lp->qli_dquot = dqp;
293 }
294 
295 /*------------------  QUOTAOFF LOG ITEMS  -------------------*/
296 
297 static inline struct xfs_qoff_logitem *QOFF_ITEM(struct xfs_log_item *lip)
298 {
299 	return container_of(lip, struct xfs_qoff_logitem, qql_item);
300 }
301 
302 
303 /*
304  * This returns the number of iovecs needed to log the given quotaoff item.
305  * We only need 1 iovec for an quotaoff item.  It just logs the
306  * quotaoff_log_format structure.
307  */
308 STATIC void
309 xfs_qm_qoff_logitem_size(
310 	struct xfs_log_item	*lip,
311 	int			*nvecs,
312 	int			*nbytes)
313 {
314 	*nvecs += 1;
315 	*nbytes += sizeof(struct xfs_qoff_logitem);
316 }
317 
318 STATIC void
319 xfs_qm_qoff_logitem_format(
320 	struct xfs_log_item	*lip,
321 	struct xfs_log_vec	*lv)
322 {
323 	struct xfs_qoff_logitem	*qflip = QOFF_ITEM(lip);
324 	struct xfs_log_iovec	*vecp = NULL;
325 	struct xfs_qoff_logformat *qlf;
326 
327 	qlf = xlog_prepare_iovec(lv, &vecp, XLOG_REG_TYPE_QUOTAOFF);
328 	qlf->qf_type = XFS_LI_QUOTAOFF;
329 	qlf->qf_size = 1;
330 	qlf->qf_flags = qflip->qql_flags;
331 	xlog_finish_iovec(lv, vecp, sizeof(struct xfs_qoff_logitem));
332 }
333 
334 /*
335  * Pinning has no meaning for an quotaoff item, so just return.
336  */
337 STATIC void
338 xfs_qm_qoff_logitem_pin(
339 	struct xfs_log_item	*lip)
340 {
341 }
342 
343 /*
344  * Since pinning has no meaning for an quotaoff item, unpinning does
345  * not either.
346  */
347 STATIC void
348 xfs_qm_qoff_logitem_unpin(
349 	struct xfs_log_item	*lip,
350 	int			remove)
351 {
352 }
353 
354 /*
355  * There isn't much you can do to push a quotaoff item.  It is simply
356  * stuck waiting for the log to be flushed to disk.
357  */
358 STATIC uint
359 xfs_qm_qoff_logitem_push(
360 	struct xfs_log_item	*lip,
361 	struct list_head	*buffer_list)
362 {
363 	return XFS_ITEM_LOCKED;
364 }
365 
366 /*
367  * Quotaoff items have no locking or pushing, so return failure
368  * so that the caller doesn't bother with us.
369  */
370 STATIC void
371 xfs_qm_qoff_logitem_unlock(
372 	struct xfs_log_item	*lip)
373 {
374 }
375 
376 /*
377  * The quotaoff-start-item is logged only once and cannot be moved in the log,
378  * so simply return the lsn at which it's been logged.
379  */
380 STATIC xfs_lsn_t
381 xfs_qm_qoff_logitem_committed(
382 	struct xfs_log_item	*lip,
383 	xfs_lsn_t		lsn)
384 {
385 	return lsn;
386 }
387 
388 STATIC xfs_lsn_t
389 xfs_qm_qoffend_logitem_committed(
390 	struct xfs_log_item	*lip,
391 	xfs_lsn_t		lsn)
392 {
393 	struct xfs_qoff_logitem	*qfe = QOFF_ITEM(lip);
394 	struct xfs_qoff_logitem	*qfs = qfe->qql_start_lip;
395 	struct xfs_ail		*ailp = qfs->qql_item.li_ailp;
396 
397 	/*
398 	 * Delete the qoff-start logitem from the AIL.
399 	 * xfs_trans_ail_delete() drops the AIL lock.
400 	 */
401 	spin_lock(&ailp->ail_lock);
402 	xfs_trans_ail_delete(ailp, &qfs->qql_item, SHUTDOWN_LOG_IO_ERROR);
403 
404 	kmem_free(qfs->qql_item.li_lv_shadow);
405 	kmem_free(lip->li_lv_shadow);
406 	kmem_free(qfs);
407 	kmem_free(qfe);
408 	return (xfs_lsn_t)-1;
409 }
410 
411 /*
412  * XXX rcc - don't know quite what to do with this.  I think we can
413  * just ignore it.  The only time that isn't the case is if we allow
414  * the client to somehow see that quotas have been turned off in which
415  * we can't allow that to get back until the quotaoff hits the disk.
416  * So how would that happen?  Also, do we need different routines for
417  * quotaoff start and quotaoff end?  I suspect the answer is yes but
418  * to be sure, I need to look at the recovery code and see how quota off
419  * recovery is handled (do we roll forward or back or do something else).
420  * If we roll forwards or backwards, then we need two separate routines,
421  * one that does nothing and one that stamps in the lsn that matters
422  * (truly makes the quotaoff irrevocable).  If we do something else,
423  * then maybe we don't need two.
424  */
425 STATIC void
426 xfs_qm_qoff_logitem_committing(
427 	struct xfs_log_item	*lip,
428 	xfs_lsn_t		commit_lsn)
429 {
430 }
431 
432 static const struct xfs_item_ops xfs_qm_qoffend_logitem_ops = {
433 	.iop_size	= xfs_qm_qoff_logitem_size,
434 	.iop_format	= xfs_qm_qoff_logitem_format,
435 	.iop_pin	= xfs_qm_qoff_logitem_pin,
436 	.iop_unpin	= xfs_qm_qoff_logitem_unpin,
437 	.iop_unlock	= xfs_qm_qoff_logitem_unlock,
438 	.iop_committed	= xfs_qm_qoffend_logitem_committed,
439 	.iop_push	= xfs_qm_qoff_logitem_push,
440 	.iop_committing = xfs_qm_qoff_logitem_committing
441 };
442 
443 /*
444  * This is the ops vector shared by all quotaoff-start log items.
445  */
446 static const struct xfs_item_ops xfs_qm_qoff_logitem_ops = {
447 	.iop_size	= xfs_qm_qoff_logitem_size,
448 	.iop_format	= xfs_qm_qoff_logitem_format,
449 	.iop_pin	= xfs_qm_qoff_logitem_pin,
450 	.iop_unpin	= xfs_qm_qoff_logitem_unpin,
451 	.iop_unlock	= xfs_qm_qoff_logitem_unlock,
452 	.iop_committed	= xfs_qm_qoff_logitem_committed,
453 	.iop_push	= xfs_qm_qoff_logitem_push,
454 	.iop_committing = xfs_qm_qoff_logitem_committing
455 };
456 
457 /*
458  * Allocate and initialize an quotaoff item of the correct quota type(s).
459  */
460 struct xfs_qoff_logitem *
461 xfs_qm_qoff_logitem_init(
462 	struct xfs_mount	*mp,
463 	struct xfs_qoff_logitem	*start,
464 	uint			flags)
465 {
466 	struct xfs_qoff_logitem	*qf;
467 
468 	qf = kmem_zalloc(sizeof(struct xfs_qoff_logitem), KM_SLEEP);
469 
470 	xfs_log_item_init(mp, &qf->qql_item, XFS_LI_QUOTAOFF, start ?
471 			&xfs_qm_qoffend_logitem_ops : &xfs_qm_qoff_logitem_ops);
472 	qf->qql_item.li_mountp = mp;
473 	qf->qql_start_lip = start;
474 	qf->qql_flags = flags;
475 	return qf;
476 }
477