xref: /openbmc/linux/fs/xfs/xfs_dquot_item.c (revision 3932b9ca)
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_sb.h"
24 #include "xfs_ag.h"
25 #include "xfs_mount.h"
26 #include "xfs_inode.h"
27 #include "xfs_quota.h"
28 #include "xfs_error.h"
29 #include "xfs_trans.h"
30 #include "xfs_buf_item.h"
31 #include "xfs_trans_priv.h"
32 #include "xfs_qm.h"
33 #include "xfs_log.h"
34 
35 static inline struct xfs_dq_logitem *DQUOT_ITEM(struct xfs_log_item *lip)
36 {
37 	return container_of(lip, struct xfs_dq_logitem, qli_item);
38 }
39 
40 /*
41  * returns the number of iovecs needed to log the given dquot item.
42  */
43 STATIC void
44 xfs_qm_dquot_logitem_size(
45 	struct xfs_log_item	*lip,
46 	int			*nvecs,
47 	int			*nbytes)
48 {
49 	*nvecs += 2;
50 	*nbytes += sizeof(struct xfs_dq_logformat) +
51 		   sizeof(struct xfs_disk_dquot);
52 }
53 
54 /*
55  * fills in the vector of log iovecs for the given dquot log item.
56  */
57 STATIC void
58 xfs_qm_dquot_logitem_format(
59 	struct xfs_log_item	*lip,
60 	struct xfs_log_vec	*lv)
61 {
62 	struct xfs_dq_logitem	*qlip = DQUOT_ITEM(lip);
63 	struct xfs_log_iovec	*vecp = NULL;
64 	struct xfs_dq_logformat	*qlf;
65 
66 	qlf = xlog_prepare_iovec(lv, &vecp, XLOG_REG_TYPE_QFORMAT);
67 	qlf->qlf_type = XFS_LI_DQUOT;
68 	qlf->qlf_size = 2;
69 	qlf->qlf_id = be32_to_cpu(qlip->qli_dquot->q_core.d_id);
70 	qlf->qlf_blkno = qlip->qli_dquot->q_blkno;
71 	qlf->qlf_len = 1;
72 	qlf->qlf_boffset = qlip->qli_dquot->q_bufoffset;
73 	xlog_finish_iovec(lv, vecp, sizeof(struct xfs_dq_logformat));
74 
75 	xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_DQUOT,
76 			&qlip->qli_dquot->q_core,
77 			sizeof(struct xfs_disk_dquot));
78 }
79 
80 /*
81  * Increment the pin count of the given dquot.
82  */
83 STATIC void
84 xfs_qm_dquot_logitem_pin(
85 	struct xfs_log_item	*lip)
86 {
87 	struct xfs_dquot	*dqp = DQUOT_ITEM(lip)->qli_dquot;
88 
89 	ASSERT(XFS_DQ_IS_LOCKED(dqp));
90 	atomic_inc(&dqp->q_pincount);
91 }
92 
93 /*
94  * Decrement the pin count of the given dquot, and wake up
95  * anyone in xfs_dqwait_unpin() if the count goes to 0.	 The
96  * dquot must have been previously pinned with a call to
97  * xfs_qm_dquot_logitem_pin().
98  */
99 STATIC void
100 xfs_qm_dquot_logitem_unpin(
101 	struct xfs_log_item	*lip,
102 	int			remove)
103 {
104 	struct xfs_dquot	*dqp = DQUOT_ITEM(lip)->qli_dquot;
105 
106 	ASSERT(atomic_read(&dqp->q_pincount) > 0);
107 	if (atomic_dec_and_test(&dqp->q_pincount))
108 		wake_up(&dqp->q_pinwait);
109 }
110 
111 STATIC xfs_lsn_t
112 xfs_qm_dquot_logitem_committed(
113 	struct xfs_log_item	*lip,
114 	xfs_lsn_t		lsn)
115 {
116 	/*
117 	 * We always re-log the entire dquot when it becomes dirty,
118 	 * so, the latest copy _is_ the only one that matters.
119 	 */
120 	return lsn;
121 }
122 
123 /*
124  * This is called to wait for the given dquot to be unpinned.
125  * Most of these pin/unpin routines are plagiarized from inode code.
126  */
127 void
128 xfs_qm_dqunpin_wait(
129 	struct xfs_dquot	*dqp)
130 {
131 	ASSERT(XFS_DQ_IS_LOCKED(dqp));
132 	if (atomic_read(&dqp->q_pincount) == 0)
133 		return;
134 
135 	/*
136 	 * Give the log a push so we don't wait here too long.
137 	 */
138 	xfs_log_force(dqp->q_mount, 0);
139 	wait_event(dqp->q_pinwait, (atomic_read(&dqp->q_pincount) == 0));
140 }
141 
142 STATIC uint
143 xfs_qm_dquot_logitem_push(
144 	struct xfs_log_item	*lip,
145 	struct list_head	*buffer_list) __releases(&lip->li_ailp->xa_lock)
146 					      __acquires(&lip->li_ailp->xa_lock)
147 {
148 	struct xfs_dquot	*dqp = DQUOT_ITEM(lip)->qli_dquot;
149 	struct xfs_buf		*bp = NULL;
150 	uint			rval = XFS_ITEM_SUCCESS;
151 	int			error;
152 
153 	if (atomic_read(&dqp->q_pincount) > 0)
154 		return XFS_ITEM_PINNED;
155 
156 	if (!xfs_dqlock_nowait(dqp))
157 		return XFS_ITEM_LOCKED;
158 
159 	/*
160 	 * Re-check the pincount now that we stabilized the value by
161 	 * taking the quota lock.
162 	 */
163 	if (atomic_read(&dqp->q_pincount) > 0) {
164 		rval = XFS_ITEM_PINNED;
165 		goto out_unlock;
166 	}
167 
168 	/*
169 	 * Someone else is already flushing the dquot.  Nothing we can do
170 	 * here but wait for the flush to finish and remove the item from
171 	 * the AIL.
172 	 */
173 	if (!xfs_dqflock_nowait(dqp)) {
174 		rval = XFS_ITEM_FLUSHING;
175 		goto out_unlock;
176 	}
177 
178 	spin_unlock(&lip->li_ailp->xa_lock);
179 
180 	error = xfs_qm_dqflush(dqp, &bp);
181 	if (error) {
182 		xfs_warn(dqp->q_mount, "%s: push error %d on dqp %p",
183 			__func__, error, dqp);
184 	} else {
185 		if (!xfs_buf_delwri_queue(bp, buffer_list))
186 			rval = XFS_ITEM_FLUSHING;
187 		xfs_buf_relse(bp);
188 	}
189 
190 	spin_lock(&lip->li_ailp->xa_lock);
191 out_unlock:
192 	xfs_dqunlock(dqp);
193 	return rval;
194 }
195 
196 /*
197  * Unlock the dquot associated with the log item.
198  * Clear the fields of the dquot and dquot log item that
199  * are specific to the current transaction.  If the
200  * hold flags is set, do not unlock the dquot.
201  */
202 STATIC void
203 xfs_qm_dquot_logitem_unlock(
204 	struct xfs_log_item	*lip)
205 {
206 	struct xfs_dquot	*dqp = DQUOT_ITEM(lip)->qli_dquot;
207 
208 	ASSERT(XFS_DQ_IS_LOCKED(dqp));
209 
210 	/*
211 	 * Clear the transaction pointer in the dquot
212 	 */
213 	dqp->q_transp = NULL;
214 
215 	/*
216 	 * dquots are never 'held' from getting unlocked at the end of
217 	 * a transaction.  Their locking and unlocking is hidden inside the
218 	 * transaction layer, within trans_commit. Hence, no LI_HOLD flag
219 	 * for the logitem.
220 	 */
221 	xfs_dqunlock(dqp);
222 }
223 
224 /*
225  * this needs to stamp an lsn into the dquot, I think.
226  * rpc's that look at user dquot's would then have to
227  * push on the dependency recorded in the dquot
228  */
229 STATIC void
230 xfs_qm_dquot_logitem_committing(
231 	struct xfs_log_item	*lip,
232 	xfs_lsn_t		lsn)
233 {
234 }
235 
236 /*
237  * This is the ops vector for dquots
238  */
239 static const struct xfs_item_ops xfs_dquot_item_ops = {
240 	.iop_size	= xfs_qm_dquot_logitem_size,
241 	.iop_format	= xfs_qm_dquot_logitem_format,
242 	.iop_pin	= xfs_qm_dquot_logitem_pin,
243 	.iop_unpin	= xfs_qm_dquot_logitem_unpin,
244 	.iop_unlock	= xfs_qm_dquot_logitem_unlock,
245 	.iop_committed	= xfs_qm_dquot_logitem_committed,
246 	.iop_push	= xfs_qm_dquot_logitem_push,
247 	.iop_committing = xfs_qm_dquot_logitem_committing
248 };
249 
250 /*
251  * Initialize the dquot log item for a newly allocated dquot.
252  * The dquot isn't locked at this point, but it isn't on any of the lists
253  * either, so we don't care.
254  */
255 void
256 xfs_qm_dquot_logitem_init(
257 	struct xfs_dquot	*dqp)
258 {
259 	struct xfs_dq_logitem	*lp = &dqp->q_logitem;
260 
261 	xfs_log_item_init(dqp->q_mount, &lp->qli_item, XFS_LI_DQUOT,
262 					&xfs_dquot_item_ops);
263 	lp->qli_dquot = dqp;
264 }
265 
266 /*------------------  QUOTAOFF LOG ITEMS  -------------------*/
267 
268 static inline struct xfs_qoff_logitem *QOFF_ITEM(struct xfs_log_item *lip)
269 {
270 	return container_of(lip, struct xfs_qoff_logitem, qql_item);
271 }
272 
273 
274 /*
275  * This returns the number of iovecs needed to log the given quotaoff item.
276  * We only need 1 iovec for an quotaoff item.  It just logs the
277  * quotaoff_log_format structure.
278  */
279 STATIC void
280 xfs_qm_qoff_logitem_size(
281 	struct xfs_log_item	*lip,
282 	int			*nvecs,
283 	int			*nbytes)
284 {
285 	*nvecs += 1;
286 	*nbytes += sizeof(struct xfs_qoff_logitem);
287 }
288 
289 STATIC void
290 xfs_qm_qoff_logitem_format(
291 	struct xfs_log_item	*lip,
292 	struct xfs_log_vec	*lv)
293 {
294 	struct xfs_qoff_logitem	*qflip = QOFF_ITEM(lip);
295 	struct xfs_log_iovec	*vecp = NULL;
296 	struct xfs_qoff_logformat *qlf;
297 
298 	qlf = xlog_prepare_iovec(lv, &vecp, XLOG_REG_TYPE_QUOTAOFF);
299 	qlf->qf_type = XFS_LI_QUOTAOFF;
300 	qlf->qf_size = 1;
301 	qlf->qf_flags = qflip->qql_flags;
302 	xlog_finish_iovec(lv, vecp, sizeof(struct xfs_qoff_logitem));
303 }
304 
305 /*
306  * Pinning has no meaning for an quotaoff item, so just return.
307  */
308 STATIC void
309 xfs_qm_qoff_logitem_pin(
310 	struct xfs_log_item	*lip)
311 {
312 }
313 
314 /*
315  * Since pinning has no meaning for an quotaoff item, unpinning does
316  * not either.
317  */
318 STATIC void
319 xfs_qm_qoff_logitem_unpin(
320 	struct xfs_log_item	*lip,
321 	int			remove)
322 {
323 }
324 
325 /*
326  * There isn't much you can do to push a quotaoff item.  It is simply
327  * stuck waiting for the log to be flushed to disk.
328  */
329 STATIC uint
330 xfs_qm_qoff_logitem_push(
331 	struct xfs_log_item	*lip,
332 	struct list_head	*buffer_list)
333 {
334 	return XFS_ITEM_LOCKED;
335 }
336 
337 /*
338  * Quotaoff items have no locking or pushing, so return failure
339  * so that the caller doesn't bother with us.
340  */
341 STATIC void
342 xfs_qm_qoff_logitem_unlock(
343 	struct xfs_log_item	*lip)
344 {
345 }
346 
347 /*
348  * The quotaoff-start-item is logged only once and cannot be moved in the log,
349  * so simply return the lsn at which it's been logged.
350  */
351 STATIC xfs_lsn_t
352 xfs_qm_qoff_logitem_committed(
353 	struct xfs_log_item	*lip,
354 	xfs_lsn_t		lsn)
355 {
356 	return lsn;
357 }
358 
359 STATIC xfs_lsn_t
360 xfs_qm_qoffend_logitem_committed(
361 	struct xfs_log_item	*lip,
362 	xfs_lsn_t		lsn)
363 {
364 	struct xfs_qoff_logitem	*qfe = QOFF_ITEM(lip);
365 	struct xfs_qoff_logitem	*qfs = qfe->qql_start_lip;
366 	struct xfs_ail		*ailp = qfs->qql_item.li_ailp;
367 
368 	/*
369 	 * Delete the qoff-start logitem from the AIL.
370 	 * xfs_trans_ail_delete() drops the AIL lock.
371 	 */
372 	spin_lock(&ailp->xa_lock);
373 	xfs_trans_ail_delete(ailp, &qfs->qql_item, SHUTDOWN_LOG_IO_ERROR);
374 
375 	kmem_free(qfs);
376 	kmem_free(qfe);
377 	return (xfs_lsn_t)-1;
378 }
379 
380 /*
381  * XXX rcc - don't know quite what to do with this.  I think we can
382  * just ignore it.  The only time that isn't the case is if we allow
383  * the client to somehow see that quotas have been turned off in which
384  * we can't allow that to get back until the quotaoff hits the disk.
385  * So how would that happen?  Also, do we need different routines for
386  * quotaoff start and quotaoff end?  I suspect the answer is yes but
387  * to be sure, I need to look at the recovery code and see how quota off
388  * recovery is handled (do we roll forward or back or do something else).
389  * If we roll forwards or backwards, then we need two separate routines,
390  * one that does nothing and one that stamps in the lsn that matters
391  * (truly makes the quotaoff irrevocable).  If we do something else,
392  * then maybe we don't need two.
393  */
394 STATIC void
395 xfs_qm_qoff_logitem_committing(
396 	struct xfs_log_item	*lip,
397 	xfs_lsn_t		commit_lsn)
398 {
399 }
400 
401 static const struct xfs_item_ops xfs_qm_qoffend_logitem_ops = {
402 	.iop_size	= xfs_qm_qoff_logitem_size,
403 	.iop_format	= xfs_qm_qoff_logitem_format,
404 	.iop_pin	= xfs_qm_qoff_logitem_pin,
405 	.iop_unpin	= xfs_qm_qoff_logitem_unpin,
406 	.iop_unlock	= xfs_qm_qoff_logitem_unlock,
407 	.iop_committed	= xfs_qm_qoffend_logitem_committed,
408 	.iop_push	= xfs_qm_qoff_logitem_push,
409 	.iop_committing = xfs_qm_qoff_logitem_committing
410 };
411 
412 /*
413  * This is the ops vector shared by all quotaoff-start log items.
414  */
415 static const struct xfs_item_ops xfs_qm_qoff_logitem_ops = {
416 	.iop_size	= xfs_qm_qoff_logitem_size,
417 	.iop_format	= xfs_qm_qoff_logitem_format,
418 	.iop_pin	= xfs_qm_qoff_logitem_pin,
419 	.iop_unpin	= xfs_qm_qoff_logitem_unpin,
420 	.iop_unlock	= xfs_qm_qoff_logitem_unlock,
421 	.iop_committed	= xfs_qm_qoff_logitem_committed,
422 	.iop_push	= xfs_qm_qoff_logitem_push,
423 	.iop_committing = xfs_qm_qoff_logitem_committing
424 };
425 
426 /*
427  * Allocate and initialize an quotaoff item of the correct quota type(s).
428  */
429 struct xfs_qoff_logitem *
430 xfs_qm_qoff_logitem_init(
431 	struct xfs_mount	*mp,
432 	struct xfs_qoff_logitem	*start,
433 	uint			flags)
434 {
435 	struct xfs_qoff_logitem	*qf;
436 
437 	qf = kmem_zalloc(sizeof(struct xfs_qoff_logitem), KM_SLEEP);
438 
439 	xfs_log_item_init(mp, &qf->qql_item, XFS_LI_QUOTAOFF, start ?
440 			&xfs_qm_qoffend_logitem_ops : &xfs_qm_qoff_logitem_ops);
441 	qf->qql_item.li_mountp = mp;
442 	qf->qql_start_lip = start;
443 	qf->qql_flags = flags;
444 	return qf;
445 }
446