xref: /openbmc/linux/fs/xfs/xfs_dquot_item.c (revision cfbb9be8)
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) __releases(&lip->li_ailp->xa_lock)
161 					      __acquires(&lip->li_ailp->xa_lock)
162 {
163 	struct xfs_dquot	*dqp = DQUOT_ITEM(lip)->qli_dquot;
164 	struct xfs_buf		*bp = lip->li_buf;
165 	uint			rval = XFS_ITEM_SUCCESS;
166 	int			error;
167 
168 	if (atomic_read(&dqp->q_pincount) > 0)
169 		return XFS_ITEM_PINNED;
170 
171 	/*
172 	 * The buffer containing this item failed to be written back
173 	 * previously. Resubmit the buffer for IO
174 	 */
175 	if (lip->li_flags & XFS_LI_FAILED) {
176 		if (!xfs_buf_trylock(bp))
177 			return XFS_ITEM_LOCKED;
178 
179 		if (!xfs_buf_resubmit_failed_buffers(bp, buffer_list))
180 			rval = XFS_ITEM_FLUSHING;
181 
182 		xfs_buf_unlock(bp);
183 		return rval;
184 	}
185 
186 	if (!xfs_dqlock_nowait(dqp))
187 		return XFS_ITEM_LOCKED;
188 
189 	/*
190 	 * Re-check the pincount now that we stabilized the value by
191 	 * taking the quota lock.
192 	 */
193 	if (atomic_read(&dqp->q_pincount) > 0) {
194 		rval = XFS_ITEM_PINNED;
195 		goto out_unlock;
196 	}
197 
198 	/*
199 	 * Someone else is already flushing the dquot.  Nothing we can do
200 	 * here but wait for the flush to finish and remove the item from
201 	 * the AIL.
202 	 */
203 	if (!xfs_dqflock_nowait(dqp)) {
204 		rval = XFS_ITEM_FLUSHING;
205 		goto out_unlock;
206 	}
207 
208 	spin_unlock(&lip->li_ailp->xa_lock);
209 
210 	error = xfs_qm_dqflush(dqp, &bp);
211 	if (error) {
212 		xfs_warn(dqp->q_mount, "%s: push error %d on dqp "PTR_FMT,
213 			__func__, error, dqp);
214 	} else {
215 		if (!xfs_buf_delwri_queue(bp, buffer_list))
216 			rval = XFS_ITEM_FLUSHING;
217 		xfs_buf_relse(bp);
218 	}
219 
220 	spin_lock(&lip->li_ailp->xa_lock);
221 out_unlock:
222 	xfs_dqunlock(dqp);
223 	return rval;
224 }
225 
226 /*
227  * Unlock the dquot associated with the log item.
228  * Clear the fields of the dquot and dquot log item that
229  * are specific to the current transaction.  If the
230  * hold flags is set, do not unlock the dquot.
231  */
232 STATIC void
233 xfs_qm_dquot_logitem_unlock(
234 	struct xfs_log_item	*lip)
235 {
236 	struct xfs_dquot	*dqp = DQUOT_ITEM(lip)->qli_dquot;
237 
238 	ASSERT(XFS_DQ_IS_LOCKED(dqp));
239 
240 	/*
241 	 * Clear the transaction pointer in the dquot
242 	 */
243 	dqp->q_transp = NULL;
244 
245 	/*
246 	 * dquots are never 'held' from getting unlocked at the end of
247 	 * a transaction.  Their locking and unlocking is hidden inside the
248 	 * transaction layer, within trans_commit. Hence, no LI_HOLD flag
249 	 * for the logitem.
250 	 */
251 	xfs_dqunlock(dqp);
252 }
253 
254 /*
255  * this needs to stamp an lsn into the dquot, I think.
256  * rpc's that look at user dquot's would then have to
257  * push on the dependency recorded in the dquot
258  */
259 STATIC void
260 xfs_qm_dquot_logitem_committing(
261 	struct xfs_log_item	*lip,
262 	xfs_lsn_t		lsn)
263 {
264 }
265 
266 /*
267  * This is the ops vector for dquots
268  */
269 static const struct xfs_item_ops xfs_dquot_item_ops = {
270 	.iop_size	= xfs_qm_dquot_logitem_size,
271 	.iop_format	= xfs_qm_dquot_logitem_format,
272 	.iop_pin	= xfs_qm_dquot_logitem_pin,
273 	.iop_unpin	= xfs_qm_dquot_logitem_unpin,
274 	.iop_unlock	= xfs_qm_dquot_logitem_unlock,
275 	.iop_committed	= xfs_qm_dquot_logitem_committed,
276 	.iop_push	= xfs_qm_dquot_logitem_push,
277 	.iop_committing = xfs_qm_dquot_logitem_committing,
278 	.iop_error	= xfs_dquot_item_error
279 };
280 
281 /*
282  * Initialize the dquot log item for a newly allocated dquot.
283  * The dquot isn't locked at this point, but it isn't on any of the lists
284  * either, so we don't care.
285  */
286 void
287 xfs_qm_dquot_logitem_init(
288 	struct xfs_dquot	*dqp)
289 {
290 	struct xfs_dq_logitem	*lp = &dqp->q_logitem;
291 
292 	xfs_log_item_init(dqp->q_mount, &lp->qli_item, XFS_LI_DQUOT,
293 					&xfs_dquot_item_ops);
294 	lp->qli_dquot = dqp;
295 }
296 
297 /*------------------  QUOTAOFF LOG ITEMS  -------------------*/
298 
299 static inline struct xfs_qoff_logitem *QOFF_ITEM(struct xfs_log_item *lip)
300 {
301 	return container_of(lip, struct xfs_qoff_logitem, qql_item);
302 }
303 
304 
305 /*
306  * This returns the number of iovecs needed to log the given quotaoff item.
307  * We only need 1 iovec for an quotaoff item.  It just logs the
308  * quotaoff_log_format structure.
309  */
310 STATIC void
311 xfs_qm_qoff_logitem_size(
312 	struct xfs_log_item	*lip,
313 	int			*nvecs,
314 	int			*nbytes)
315 {
316 	*nvecs += 1;
317 	*nbytes += sizeof(struct xfs_qoff_logitem);
318 }
319 
320 STATIC void
321 xfs_qm_qoff_logitem_format(
322 	struct xfs_log_item	*lip,
323 	struct xfs_log_vec	*lv)
324 {
325 	struct xfs_qoff_logitem	*qflip = QOFF_ITEM(lip);
326 	struct xfs_log_iovec	*vecp = NULL;
327 	struct xfs_qoff_logformat *qlf;
328 
329 	qlf = xlog_prepare_iovec(lv, &vecp, XLOG_REG_TYPE_QUOTAOFF);
330 	qlf->qf_type = XFS_LI_QUOTAOFF;
331 	qlf->qf_size = 1;
332 	qlf->qf_flags = qflip->qql_flags;
333 	xlog_finish_iovec(lv, vecp, sizeof(struct xfs_qoff_logitem));
334 }
335 
336 /*
337  * Pinning has no meaning for an quotaoff item, so just return.
338  */
339 STATIC void
340 xfs_qm_qoff_logitem_pin(
341 	struct xfs_log_item	*lip)
342 {
343 }
344 
345 /*
346  * Since pinning has no meaning for an quotaoff item, unpinning does
347  * not either.
348  */
349 STATIC void
350 xfs_qm_qoff_logitem_unpin(
351 	struct xfs_log_item	*lip,
352 	int			remove)
353 {
354 }
355 
356 /*
357  * There isn't much you can do to push a quotaoff item.  It is simply
358  * stuck waiting for the log to be flushed to disk.
359  */
360 STATIC uint
361 xfs_qm_qoff_logitem_push(
362 	struct xfs_log_item	*lip,
363 	struct list_head	*buffer_list)
364 {
365 	return XFS_ITEM_LOCKED;
366 }
367 
368 /*
369  * Quotaoff items have no locking or pushing, so return failure
370  * so that the caller doesn't bother with us.
371  */
372 STATIC void
373 xfs_qm_qoff_logitem_unlock(
374 	struct xfs_log_item	*lip)
375 {
376 }
377 
378 /*
379  * The quotaoff-start-item is logged only once and cannot be moved in the log,
380  * so simply return the lsn at which it's been logged.
381  */
382 STATIC xfs_lsn_t
383 xfs_qm_qoff_logitem_committed(
384 	struct xfs_log_item	*lip,
385 	xfs_lsn_t		lsn)
386 {
387 	return lsn;
388 }
389 
390 STATIC xfs_lsn_t
391 xfs_qm_qoffend_logitem_committed(
392 	struct xfs_log_item	*lip,
393 	xfs_lsn_t		lsn)
394 {
395 	struct xfs_qoff_logitem	*qfe = QOFF_ITEM(lip);
396 	struct xfs_qoff_logitem	*qfs = qfe->qql_start_lip;
397 	struct xfs_ail		*ailp = qfs->qql_item.li_ailp;
398 
399 	/*
400 	 * Delete the qoff-start logitem from the AIL.
401 	 * xfs_trans_ail_delete() drops the AIL lock.
402 	 */
403 	spin_lock(&ailp->xa_lock);
404 	xfs_trans_ail_delete(ailp, &qfs->qql_item, SHUTDOWN_LOG_IO_ERROR);
405 
406 	kmem_free(qfs->qql_item.li_lv_shadow);
407 	kmem_free(lip->li_lv_shadow);
408 	kmem_free(qfs);
409 	kmem_free(qfe);
410 	return (xfs_lsn_t)-1;
411 }
412 
413 /*
414  * XXX rcc - don't know quite what to do with this.  I think we can
415  * just ignore it.  The only time that isn't the case is if we allow
416  * the client to somehow see that quotas have been turned off in which
417  * we can't allow that to get back until the quotaoff hits the disk.
418  * So how would that happen?  Also, do we need different routines for
419  * quotaoff start and quotaoff end?  I suspect the answer is yes but
420  * to be sure, I need to look at the recovery code and see how quota off
421  * recovery is handled (do we roll forward or back or do something else).
422  * If we roll forwards or backwards, then we need two separate routines,
423  * one that does nothing and one that stamps in the lsn that matters
424  * (truly makes the quotaoff irrevocable).  If we do something else,
425  * then maybe we don't need two.
426  */
427 STATIC void
428 xfs_qm_qoff_logitem_committing(
429 	struct xfs_log_item	*lip,
430 	xfs_lsn_t		commit_lsn)
431 {
432 }
433 
434 static const struct xfs_item_ops xfs_qm_qoffend_logitem_ops = {
435 	.iop_size	= xfs_qm_qoff_logitem_size,
436 	.iop_format	= xfs_qm_qoff_logitem_format,
437 	.iop_pin	= xfs_qm_qoff_logitem_pin,
438 	.iop_unpin	= xfs_qm_qoff_logitem_unpin,
439 	.iop_unlock	= xfs_qm_qoff_logitem_unlock,
440 	.iop_committed	= xfs_qm_qoffend_logitem_committed,
441 	.iop_push	= xfs_qm_qoff_logitem_push,
442 	.iop_committing = xfs_qm_qoff_logitem_committing
443 };
444 
445 /*
446  * This is the ops vector shared by all quotaoff-start log items.
447  */
448 static const struct xfs_item_ops xfs_qm_qoff_logitem_ops = {
449 	.iop_size	= xfs_qm_qoff_logitem_size,
450 	.iop_format	= xfs_qm_qoff_logitem_format,
451 	.iop_pin	= xfs_qm_qoff_logitem_pin,
452 	.iop_unpin	= xfs_qm_qoff_logitem_unpin,
453 	.iop_unlock	= xfs_qm_qoff_logitem_unlock,
454 	.iop_committed	= xfs_qm_qoff_logitem_committed,
455 	.iop_push	= xfs_qm_qoff_logitem_push,
456 	.iop_committing = xfs_qm_qoff_logitem_committing
457 };
458 
459 /*
460  * Allocate and initialize an quotaoff item of the correct quota type(s).
461  */
462 struct xfs_qoff_logitem *
463 xfs_qm_qoff_logitem_init(
464 	struct xfs_mount	*mp,
465 	struct xfs_qoff_logitem	*start,
466 	uint			flags)
467 {
468 	struct xfs_qoff_logitem	*qf;
469 
470 	qf = kmem_zalloc(sizeof(struct xfs_qoff_logitem), KM_SLEEP);
471 
472 	xfs_log_item_init(mp, &qf->qql_item, XFS_LI_QUOTAOFF, start ?
473 			&xfs_qm_qoffend_logitem_ops : &xfs_qm_qoff_logitem_ops);
474 	qf->qql_item.li_mountp = mp;
475 	qf->qql_start_lip = start;
476 	qf->qql_flags = flags;
477 	return qf;
478 }
479