xref: /openbmc/linux/fs/xfs/xfs_dquot_item.c (revision 9b93eb47)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2000-2003 Silicon Graphics, Inc.
4  * All Rights Reserved.
5  */
6 #include "xfs.h"
7 #include "xfs_fs.h"
8 #include "xfs_format.h"
9 #include "xfs_log_format.h"
10 #include "xfs_trans_resv.h"
11 #include "xfs_mount.h"
12 #include "xfs_inode.h"
13 #include "xfs_quota.h"
14 #include "xfs_error.h"
15 #include "xfs_trans.h"
16 #include "xfs_buf_item.h"
17 #include "xfs_trans_priv.h"
18 #include "xfs_qm.h"
19 #include "xfs_log.h"
20 
21 static inline struct xfs_dq_logitem *DQUOT_ITEM(struct xfs_log_item *lip)
22 {
23 	return container_of(lip, struct xfs_dq_logitem, qli_item);
24 }
25 
26 /*
27  * returns the number of iovecs needed to log the given dquot item.
28  */
29 STATIC void
30 xfs_qm_dquot_logitem_size(
31 	struct xfs_log_item	*lip,
32 	int			*nvecs,
33 	int			*nbytes)
34 {
35 	*nvecs += 2;
36 	*nbytes += sizeof(struct xfs_dq_logformat) +
37 		   sizeof(struct xfs_disk_dquot);
38 }
39 
40 /*
41  * fills in the vector of log iovecs for the given dquot log item.
42  */
43 STATIC void
44 xfs_qm_dquot_logitem_format(
45 	struct xfs_log_item	*lip,
46 	struct xfs_log_vec	*lv)
47 {
48 	struct xfs_dq_logitem	*qlip = DQUOT_ITEM(lip);
49 	struct xfs_log_iovec	*vecp = NULL;
50 	struct xfs_dq_logformat	*qlf;
51 
52 	qlf = xlog_prepare_iovec(lv, &vecp, XLOG_REG_TYPE_QFORMAT);
53 	qlf->qlf_type = XFS_LI_DQUOT;
54 	qlf->qlf_size = 2;
55 	qlf->qlf_id = be32_to_cpu(qlip->qli_dquot->q_core.d_id);
56 	qlf->qlf_blkno = qlip->qli_dquot->q_blkno;
57 	qlf->qlf_len = 1;
58 	qlf->qlf_boffset = qlip->qli_dquot->q_bufoffset;
59 	xlog_finish_iovec(lv, vecp, sizeof(struct xfs_dq_logformat));
60 
61 	xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_DQUOT,
62 			&qlip->qli_dquot->q_core,
63 			sizeof(struct xfs_disk_dquot));
64 }
65 
66 /*
67  * Increment the pin count of the given dquot.
68  */
69 STATIC void
70 xfs_qm_dquot_logitem_pin(
71 	struct xfs_log_item	*lip)
72 {
73 	struct xfs_dquot	*dqp = DQUOT_ITEM(lip)->qli_dquot;
74 
75 	ASSERT(XFS_DQ_IS_LOCKED(dqp));
76 	atomic_inc(&dqp->q_pincount);
77 }
78 
79 /*
80  * Decrement the pin count of the given dquot, and wake up
81  * anyone in xfs_dqwait_unpin() if the count goes to 0.	 The
82  * dquot must have been previously pinned with a call to
83  * xfs_qm_dquot_logitem_pin().
84  */
85 STATIC void
86 xfs_qm_dquot_logitem_unpin(
87 	struct xfs_log_item	*lip,
88 	int			remove)
89 {
90 	struct xfs_dquot	*dqp = DQUOT_ITEM(lip)->qli_dquot;
91 
92 	ASSERT(atomic_read(&dqp->q_pincount) > 0);
93 	if (atomic_dec_and_test(&dqp->q_pincount))
94 		wake_up(&dqp->q_pinwait);
95 }
96 
97 STATIC xfs_lsn_t
98 xfs_qm_dquot_logitem_committed(
99 	struct xfs_log_item	*lip,
100 	xfs_lsn_t		lsn)
101 {
102 	/*
103 	 * We always re-log the entire dquot when it becomes dirty,
104 	 * so, the latest copy _is_ the only one that matters.
105 	 */
106 	return lsn;
107 }
108 
109 /*
110  * This is called to wait for the given dquot to be unpinned.
111  * Most of these pin/unpin routines are plagiarized from inode code.
112  */
113 void
114 xfs_qm_dqunpin_wait(
115 	struct xfs_dquot	*dqp)
116 {
117 	ASSERT(XFS_DQ_IS_LOCKED(dqp));
118 	if (atomic_read(&dqp->q_pincount) == 0)
119 		return;
120 
121 	/*
122 	 * Give the log a push so we don't wait here too long.
123 	 */
124 	xfs_log_force(dqp->q_mount, 0);
125 	wait_event(dqp->q_pinwait, (atomic_read(&dqp->q_pincount) == 0));
126 }
127 
128 /*
129  * Callback used to mark a buffer with XFS_LI_FAILED when items in the buffer
130  * have been failed during writeback
131  *
132  * this informs the AIL that the dquot is already flush locked on the next push,
133  * and acquires a hold on the buffer to ensure that it isn't reclaimed before
134  * dirty data makes it to disk.
135  */
136 STATIC void
137 xfs_dquot_item_error(
138 	struct xfs_log_item	*lip,
139 	struct xfs_buf		*bp)
140 {
141 	ASSERT(!completion_done(&DQUOT_ITEM(lip)->qli_dquot->q_flush));
142 	xfs_set_li_failed(lip, bp);
143 }
144 
145 STATIC uint
146 xfs_qm_dquot_logitem_push(
147 	struct xfs_log_item	*lip,
148 	struct list_head	*buffer_list)
149 		__releases(&lip->li_ailp->ail_lock)
150 		__acquires(&lip->li_ailp->ail_lock)
151 {
152 	struct xfs_dquot	*dqp = DQUOT_ITEM(lip)->qli_dquot;
153 	struct xfs_buf		*bp = lip->li_buf;
154 	uint			rval = XFS_ITEM_SUCCESS;
155 	int			error;
156 
157 	if (atomic_read(&dqp->q_pincount) > 0)
158 		return XFS_ITEM_PINNED;
159 
160 	/*
161 	 * The buffer containing this item failed to be written back
162 	 * previously. Resubmit the buffer for IO
163 	 */
164 	if (test_bit(XFS_LI_FAILED, &lip->li_flags)) {
165 		if (!xfs_buf_trylock(bp))
166 			return XFS_ITEM_LOCKED;
167 
168 		if (!xfs_buf_resubmit_failed_buffers(bp, buffer_list))
169 			rval = XFS_ITEM_FLUSHING;
170 
171 		xfs_buf_unlock(bp);
172 		return rval;
173 	}
174 
175 	if (!xfs_dqlock_nowait(dqp))
176 		return XFS_ITEM_LOCKED;
177 
178 	/*
179 	 * Re-check the pincount now that we stabilized the value by
180 	 * taking the quota lock.
181 	 */
182 	if (atomic_read(&dqp->q_pincount) > 0) {
183 		rval = XFS_ITEM_PINNED;
184 		goto out_unlock;
185 	}
186 
187 	/*
188 	 * Someone else is already flushing the dquot.  Nothing we can do
189 	 * here but wait for the flush to finish and remove the item from
190 	 * the AIL.
191 	 */
192 	if (!xfs_dqflock_nowait(dqp)) {
193 		rval = XFS_ITEM_FLUSHING;
194 		goto out_unlock;
195 	}
196 
197 	spin_unlock(&lip->li_ailp->ail_lock);
198 
199 	error = xfs_qm_dqflush(dqp, &bp);
200 	if (!error) {
201 		if (!xfs_buf_delwri_queue(bp, buffer_list))
202 			rval = XFS_ITEM_FLUSHING;
203 		xfs_buf_relse(bp);
204 	}
205 
206 	spin_lock(&lip->li_ailp->ail_lock);
207 out_unlock:
208 	xfs_dqunlock(dqp);
209 	return rval;
210 }
211 
212 /*
213  * Unlock the dquot associated with the log item.
214  * Clear the fields of the dquot and dquot log item that
215  * are specific to the current transaction.  If the
216  * hold flags is set, do not unlock the dquot.
217  */
218 STATIC void
219 xfs_qm_dquot_logitem_unlock(
220 	struct xfs_log_item	*lip)
221 {
222 	struct xfs_dquot	*dqp = DQUOT_ITEM(lip)->qli_dquot;
223 
224 	ASSERT(XFS_DQ_IS_LOCKED(dqp));
225 
226 	/*
227 	 * Clear the transaction pointer in the dquot
228 	 */
229 	dqp->q_transp = NULL;
230 
231 	/*
232 	 * dquots are never 'held' from getting unlocked at the end of
233 	 * a transaction.  Their locking and unlocking is hidden inside the
234 	 * transaction layer, within trans_commit. Hence, no LI_HOLD flag
235 	 * for the logitem.
236 	 */
237 	xfs_dqunlock(dqp);
238 }
239 
240 /*
241  * this needs to stamp an lsn into the dquot, I think.
242  * rpc's that look at user dquot's would then have to
243  * push on the dependency recorded in the dquot
244  */
245 STATIC void
246 xfs_qm_dquot_logitem_committing(
247 	struct xfs_log_item	*lip,
248 	xfs_lsn_t		lsn)
249 {
250 }
251 
252 /*
253  * This is the ops vector for dquots
254  */
255 static const struct xfs_item_ops xfs_dquot_item_ops = {
256 	.iop_size	= xfs_qm_dquot_logitem_size,
257 	.iop_format	= xfs_qm_dquot_logitem_format,
258 	.iop_pin	= xfs_qm_dquot_logitem_pin,
259 	.iop_unpin	= xfs_qm_dquot_logitem_unpin,
260 	.iop_unlock	= xfs_qm_dquot_logitem_unlock,
261 	.iop_committed	= xfs_qm_dquot_logitem_committed,
262 	.iop_push	= xfs_qm_dquot_logitem_push,
263 	.iop_committing = xfs_qm_dquot_logitem_committing,
264 	.iop_error	= xfs_dquot_item_error
265 };
266 
267 /*
268  * Initialize the dquot log item for a newly allocated dquot.
269  * The dquot isn't locked at this point, but it isn't on any of the lists
270  * either, so we don't care.
271  */
272 void
273 xfs_qm_dquot_logitem_init(
274 	struct xfs_dquot	*dqp)
275 {
276 	struct xfs_dq_logitem	*lp = &dqp->q_logitem;
277 
278 	xfs_log_item_init(dqp->q_mount, &lp->qli_item, XFS_LI_DQUOT,
279 					&xfs_dquot_item_ops);
280 	lp->qli_dquot = dqp;
281 }
282 
283 /*------------------  QUOTAOFF LOG ITEMS  -------------------*/
284 
285 static inline struct xfs_qoff_logitem *QOFF_ITEM(struct xfs_log_item *lip)
286 {
287 	return container_of(lip, struct xfs_qoff_logitem, qql_item);
288 }
289 
290 
291 /*
292  * This returns the number of iovecs needed to log the given quotaoff item.
293  * We only need 1 iovec for an quotaoff item.  It just logs the
294  * quotaoff_log_format structure.
295  */
296 STATIC void
297 xfs_qm_qoff_logitem_size(
298 	struct xfs_log_item	*lip,
299 	int			*nvecs,
300 	int			*nbytes)
301 {
302 	*nvecs += 1;
303 	*nbytes += sizeof(struct xfs_qoff_logitem);
304 }
305 
306 STATIC void
307 xfs_qm_qoff_logitem_format(
308 	struct xfs_log_item	*lip,
309 	struct xfs_log_vec	*lv)
310 {
311 	struct xfs_qoff_logitem	*qflip = QOFF_ITEM(lip);
312 	struct xfs_log_iovec	*vecp = NULL;
313 	struct xfs_qoff_logformat *qlf;
314 
315 	qlf = xlog_prepare_iovec(lv, &vecp, XLOG_REG_TYPE_QUOTAOFF);
316 	qlf->qf_type = XFS_LI_QUOTAOFF;
317 	qlf->qf_size = 1;
318 	qlf->qf_flags = qflip->qql_flags;
319 	xlog_finish_iovec(lv, vecp, sizeof(struct xfs_qoff_logitem));
320 }
321 
322 /*
323  * Pinning has no meaning for an quotaoff item, so just return.
324  */
325 STATIC void
326 xfs_qm_qoff_logitem_pin(
327 	struct xfs_log_item	*lip)
328 {
329 }
330 
331 /*
332  * Since pinning has no meaning for an quotaoff item, unpinning does
333  * not either.
334  */
335 STATIC void
336 xfs_qm_qoff_logitem_unpin(
337 	struct xfs_log_item	*lip,
338 	int			remove)
339 {
340 }
341 
342 /*
343  * There isn't much you can do to push a quotaoff item.  It is simply
344  * stuck waiting for the log to be flushed to disk.
345  */
346 STATIC uint
347 xfs_qm_qoff_logitem_push(
348 	struct xfs_log_item	*lip,
349 	struct list_head	*buffer_list)
350 {
351 	return XFS_ITEM_LOCKED;
352 }
353 
354 /*
355  * Quotaoff items have no locking or pushing, so return failure
356  * so that the caller doesn't bother with us.
357  */
358 STATIC void
359 xfs_qm_qoff_logitem_unlock(
360 	struct xfs_log_item	*lip)
361 {
362 }
363 
364 /*
365  * The quotaoff-start-item is logged only once and cannot be moved in the log,
366  * so simply return the lsn at which it's been logged.
367  */
368 STATIC xfs_lsn_t
369 xfs_qm_qoff_logitem_committed(
370 	struct xfs_log_item	*lip,
371 	xfs_lsn_t		lsn)
372 {
373 	return lsn;
374 }
375 
376 STATIC xfs_lsn_t
377 xfs_qm_qoffend_logitem_committed(
378 	struct xfs_log_item	*lip,
379 	xfs_lsn_t		lsn)
380 {
381 	struct xfs_qoff_logitem	*qfe = QOFF_ITEM(lip);
382 	struct xfs_qoff_logitem	*qfs = qfe->qql_start_lip;
383 	struct xfs_ail		*ailp = qfs->qql_item.li_ailp;
384 
385 	/*
386 	 * Delete the qoff-start logitem from the AIL.
387 	 * xfs_trans_ail_delete() drops the AIL lock.
388 	 */
389 	spin_lock(&ailp->ail_lock);
390 	xfs_trans_ail_delete(ailp, &qfs->qql_item, SHUTDOWN_LOG_IO_ERROR);
391 
392 	kmem_free(qfs->qql_item.li_lv_shadow);
393 	kmem_free(lip->li_lv_shadow);
394 	kmem_free(qfs);
395 	kmem_free(qfe);
396 	return (xfs_lsn_t)-1;
397 }
398 
399 /*
400  * XXX rcc - don't know quite what to do with this.  I think we can
401  * just ignore it.  The only time that isn't the case is if we allow
402  * the client to somehow see that quotas have been turned off in which
403  * we can't allow that to get back until the quotaoff hits the disk.
404  * So how would that happen?  Also, do we need different routines for
405  * quotaoff start and quotaoff end?  I suspect the answer is yes but
406  * to be sure, I need to look at the recovery code and see how quota off
407  * recovery is handled (do we roll forward or back or do something else).
408  * If we roll forwards or backwards, then we need two separate routines,
409  * one that does nothing and one that stamps in the lsn that matters
410  * (truly makes the quotaoff irrevocable).  If we do something else,
411  * then maybe we don't need two.
412  */
413 STATIC void
414 xfs_qm_qoff_logitem_committing(
415 	struct xfs_log_item	*lip,
416 	xfs_lsn_t		commit_lsn)
417 {
418 }
419 
420 static const struct xfs_item_ops xfs_qm_qoffend_logitem_ops = {
421 	.iop_size	= xfs_qm_qoff_logitem_size,
422 	.iop_format	= xfs_qm_qoff_logitem_format,
423 	.iop_pin	= xfs_qm_qoff_logitem_pin,
424 	.iop_unpin	= xfs_qm_qoff_logitem_unpin,
425 	.iop_unlock	= xfs_qm_qoff_logitem_unlock,
426 	.iop_committed	= xfs_qm_qoffend_logitem_committed,
427 	.iop_push	= xfs_qm_qoff_logitem_push,
428 	.iop_committing = xfs_qm_qoff_logitem_committing
429 };
430 
431 /*
432  * This is the ops vector shared by all quotaoff-start log items.
433  */
434 static const struct xfs_item_ops xfs_qm_qoff_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_qoff_logitem_committed,
441 	.iop_push	= xfs_qm_qoff_logitem_push,
442 	.iop_committing = xfs_qm_qoff_logitem_committing
443 };
444 
445 /*
446  * Allocate and initialize an quotaoff item of the correct quota type(s).
447  */
448 struct xfs_qoff_logitem *
449 xfs_qm_qoff_logitem_init(
450 	struct xfs_mount	*mp,
451 	struct xfs_qoff_logitem	*start,
452 	uint			flags)
453 {
454 	struct xfs_qoff_logitem	*qf;
455 
456 	qf = kmem_zalloc(sizeof(struct xfs_qoff_logitem), KM_SLEEP);
457 
458 	xfs_log_item_init(mp, &qf->qql_item, XFS_LI_QUOTAOFF, start ?
459 			&xfs_qm_qoffend_logitem_ops : &xfs_qm_qoff_logitem_ops);
460 	qf->qql_item.li_mountp = mp;
461 	qf->qql_start_lip = start;
462 	qf->qql_flags = flags;
463 	return qf;
464 }
465