xref: /openbmc/linux/fs/xfs/xfs_dquot_item.c (revision 03cb0503)
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 STATIC uint
141 xfs_qm_dquot_logitem_push(
142 	struct xfs_log_item	*lip,
143 	struct list_head	*buffer_list) __releases(&lip->li_ailp->xa_lock)
144 					      __acquires(&lip->li_ailp->xa_lock)
145 {
146 	struct xfs_dquot	*dqp = DQUOT_ITEM(lip)->qli_dquot;
147 	struct xfs_buf		*bp = NULL;
148 	uint			rval = XFS_ITEM_SUCCESS;
149 	int			error;
150 
151 	if (atomic_read(&dqp->q_pincount) > 0)
152 		return XFS_ITEM_PINNED;
153 
154 	if (!xfs_dqlock_nowait(dqp))
155 		return XFS_ITEM_LOCKED;
156 
157 	/*
158 	 * Re-check the pincount now that we stabilized the value by
159 	 * taking the quota lock.
160 	 */
161 	if (atomic_read(&dqp->q_pincount) > 0) {
162 		rval = XFS_ITEM_PINNED;
163 		goto out_unlock;
164 	}
165 
166 	/*
167 	 * Someone else is already flushing the dquot.  Nothing we can do
168 	 * here but wait for the flush to finish and remove the item from
169 	 * the AIL.
170 	 */
171 	if (!xfs_dqflock_nowait(dqp)) {
172 		rval = XFS_ITEM_FLUSHING;
173 		goto out_unlock;
174 	}
175 
176 	spin_unlock(&lip->li_ailp->xa_lock);
177 
178 	error = xfs_qm_dqflush(dqp, &bp);
179 	if (error) {
180 		xfs_warn(dqp->q_mount, "%s: push error %d on dqp %p",
181 			__func__, error, dqp);
182 	} else {
183 		if (!xfs_buf_delwri_queue(bp, buffer_list))
184 			rval = XFS_ITEM_FLUSHING;
185 		xfs_buf_relse(bp);
186 	}
187 
188 	spin_lock(&lip->li_ailp->xa_lock);
189 out_unlock:
190 	xfs_dqunlock(dqp);
191 	return rval;
192 }
193 
194 /*
195  * Unlock the dquot associated with the log item.
196  * Clear the fields of the dquot and dquot log item that
197  * are specific to the current transaction.  If the
198  * hold flags is set, do not unlock the dquot.
199  */
200 STATIC void
201 xfs_qm_dquot_logitem_unlock(
202 	struct xfs_log_item	*lip)
203 {
204 	struct xfs_dquot	*dqp = DQUOT_ITEM(lip)->qli_dquot;
205 
206 	ASSERT(XFS_DQ_IS_LOCKED(dqp));
207 
208 	/*
209 	 * Clear the transaction pointer in the dquot
210 	 */
211 	dqp->q_transp = NULL;
212 
213 	/*
214 	 * dquots are never 'held' from getting unlocked at the end of
215 	 * a transaction.  Their locking and unlocking is hidden inside the
216 	 * transaction layer, within trans_commit. Hence, no LI_HOLD flag
217 	 * for the logitem.
218 	 */
219 	xfs_dqunlock(dqp);
220 }
221 
222 /*
223  * this needs to stamp an lsn into the dquot, I think.
224  * rpc's that look at user dquot's would then have to
225  * push on the dependency recorded in the dquot
226  */
227 STATIC void
228 xfs_qm_dquot_logitem_committing(
229 	struct xfs_log_item	*lip,
230 	xfs_lsn_t		lsn)
231 {
232 }
233 
234 /*
235  * This is the ops vector for dquots
236  */
237 static const struct xfs_item_ops xfs_dquot_item_ops = {
238 	.iop_size	= xfs_qm_dquot_logitem_size,
239 	.iop_format	= xfs_qm_dquot_logitem_format,
240 	.iop_pin	= xfs_qm_dquot_logitem_pin,
241 	.iop_unpin	= xfs_qm_dquot_logitem_unpin,
242 	.iop_unlock	= xfs_qm_dquot_logitem_unlock,
243 	.iop_committed	= xfs_qm_dquot_logitem_committed,
244 	.iop_push	= xfs_qm_dquot_logitem_push,
245 	.iop_committing = xfs_qm_dquot_logitem_committing
246 };
247 
248 /*
249  * Initialize the dquot log item for a newly allocated dquot.
250  * The dquot isn't locked at this point, but it isn't on any of the lists
251  * either, so we don't care.
252  */
253 void
254 xfs_qm_dquot_logitem_init(
255 	struct xfs_dquot	*dqp)
256 {
257 	struct xfs_dq_logitem	*lp = &dqp->q_logitem;
258 
259 	xfs_log_item_init(dqp->q_mount, &lp->qli_item, XFS_LI_DQUOT,
260 					&xfs_dquot_item_ops);
261 	lp->qli_dquot = dqp;
262 }
263 
264 /*------------------  QUOTAOFF LOG ITEMS  -------------------*/
265 
266 static inline struct xfs_qoff_logitem *QOFF_ITEM(struct xfs_log_item *lip)
267 {
268 	return container_of(lip, struct xfs_qoff_logitem, qql_item);
269 }
270 
271 
272 /*
273  * This returns the number of iovecs needed to log the given quotaoff item.
274  * We only need 1 iovec for an quotaoff item.  It just logs the
275  * quotaoff_log_format structure.
276  */
277 STATIC void
278 xfs_qm_qoff_logitem_size(
279 	struct xfs_log_item	*lip,
280 	int			*nvecs,
281 	int			*nbytes)
282 {
283 	*nvecs += 1;
284 	*nbytes += sizeof(struct xfs_qoff_logitem);
285 }
286 
287 STATIC void
288 xfs_qm_qoff_logitem_format(
289 	struct xfs_log_item	*lip,
290 	struct xfs_log_vec	*lv)
291 {
292 	struct xfs_qoff_logitem	*qflip = QOFF_ITEM(lip);
293 	struct xfs_log_iovec	*vecp = NULL;
294 	struct xfs_qoff_logformat *qlf;
295 
296 	qlf = xlog_prepare_iovec(lv, &vecp, XLOG_REG_TYPE_QUOTAOFF);
297 	qlf->qf_type = XFS_LI_QUOTAOFF;
298 	qlf->qf_size = 1;
299 	qlf->qf_flags = qflip->qql_flags;
300 	xlog_finish_iovec(lv, vecp, sizeof(struct xfs_qoff_logitem));
301 }
302 
303 /*
304  * Pinning has no meaning for an quotaoff item, so just return.
305  */
306 STATIC void
307 xfs_qm_qoff_logitem_pin(
308 	struct xfs_log_item	*lip)
309 {
310 }
311 
312 /*
313  * Since pinning has no meaning for an quotaoff item, unpinning does
314  * not either.
315  */
316 STATIC void
317 xfs_qm_qoff_logitem_unpin(
318 	struct xfs_log_item	*lip,
319 	int			remove)
320 {
321 }
322 
323 /*
324  * There isn't much you can do to push a quotaoff item.  It is simply
325  * stuck waiting for the log to be flushed to disk.
326  */
327 STATIC uint
328 xfs_qm_qoff_logitem_push(
329 	struct xfs_log_item	*lip,
330 	struct list_head	*buffer_list)
331 {
332 	return XFS_ITEM_LOCKED;
333 }
334 
335 /*
336  * Quotaoff items have no locking or pushing, so return failure
337  * so that the caller doesn't bother with us.
338  */
339 STATIC void
340 xfs_qm_qoff_logitem_unlock(
341 	struct xfs_log_item	*lip)
342 {
343 }
344 
345 /*
346  * The quotaoff-start-item is logged only once and cannot be moved in the log,
347  * so simply return the lsn at which it's been logged.
348  */
349 STATIC xfs_lsn_t
350 xfs_qm_qoff_logitem_committed(
351 	struct xfs_log_item	*lip,
352 	xfs_lsn_t		lsn)
353 {
354 	return lsn;
355 }
356 
357 STATIC xfs_lsn_t
358 xfs_qm_qoffend_logitem_committed(
359 	struct xfs_log_item	*lip,
360 	xfs_lsn_t		lsn)
361 {
362 	struct xfs_qoff_logitem	*qfe = QOFF_ITEM(lip);
363 	struct xfs_qoff_logitem	*qfs = qfe->qql_start_lip;
364 	struct xfs_ail		*ailp = qfs->qql_item.li_ailp;
365 
366 	/*
367 	 * Delete the qoff-start logitem from the AIL.
368 	 * xfs_trans_ail_delete() drops the AIL lock.
369 	 */
370 	spin_lock(&ailp->xa_lock);
371 	xfs_trans_ail_delete(ailp, &qfs->qql_item, SHUTDOWN_LOG_IO_ERROR);
372 
373 	kmem_free(qfs);
374 	kmem_free(qfe);
375 	return (xfs_lsn_t)-1;
376 }
377 
378 /*
379  * XXX rcc - don't know quite what to do with this.  I think we can
380  * just ignore it.  The only time that isn't the case is if we allow
381  * the client to somehow see that quotas have been turned off in which
382  * we can't allow that to get back until the quotaoff hits the disk.
383  * So how would that happen?  Also, do we need different routines for
384  * quotaoff start and quotaoff end?  I suspect the answer is yes but
385  * to be sure, I need to look at the recovery code and see how quota off
386  * recovery is handled (do we roll forward or back or do something else).
387  * If we roll forwards or backwards, then we need two separate routines,
388  * one that does nothing and one that stamps in the lsn that matters
389  * (truly makes the quotaoff irrevocable).  If we do something else,
390  * then maybe we don't need two.
391  */
392 STATIC void
393 xfs_qm_qoff_logitem_committing(
394 	struct xfs_log_item	*lip,
395 	xfs_lsn_t		commit_lsn)
396 {
397 }
398 
399 static const struct xfs_item_ops xfs_qm_qoffend_logitem_ops = {
400 	.iop_size	= xfs_qm_qoff_logitem_size,
401 	.iop_format	= xfs_qm_qoff_logitem_format,
402 	.iop_pin	= xfs_qm_qoff_logitem_pin,
403 	.iop_unpin	= xfs_qm_qoff_logitem_unpin,
404 	.iop_unlock	= xfs_qm_qoff_logitem_unlock,
405 	.iop_committed	= xfs_qm_qoffend_logitem_committed,
406 	.iop_push	= xfs_qm_qoff_logitem_push,
407 	.iop_committing = xfs_qm_qoff_logitem_committing
408 };
409 
410 /*
411  * This is the ops vector shared by all quotaoff-start log items.
412  */
413 static const struct xfs_item_ops xfs_qm_qoff_logitem_ops = {
414 	.iop_size	= xfs_qm_qoff_logitem_size,
415 	.iop_format	= xfs_qm_qoff_logitem_format,
416 	.iop_pin	= xfs_qm_qoff_logitem_pin,
417 	.iop_unpin	= xfs_qm_qoff_logitem_unpin,
418 	.iop_unlock	= xfs_qm_qoff_logitem_unlock,
419 	.iop_committed	= xfs_qm_qoff_logitem_committed,
420 	.iop_push	= xfs_qm_qoff_logitem_push,
421 	.iop_committing = xfs_qm_qoff_logitem_committing
422 };
423 
424 /*
425  * Allocate and initialize an quotaoff item of the correct quota type(s).
426  */
427 struct xfs_qoff_logitem *
428 xfs_qm_qoff_logitem_init(
429 	struct xfs_mount	*mp,
430 	struct xfs_qoff_logitem	*start,
431 	uint			flags)
432 {
433 	struct xfs_qoff_logitem	*qf;
434 
435 	qf = kmem_zalloc(sizeof(struct xfs_qoff_logitem), KM_SLEEP);
436 
437 	xfs_log_item_init(mp, &qf->qql_item, XFS_LI_QUOTAOFF, start ?
438 			&xfs_qm_qoffend_logitem_ops : &xfs_qm_qoff_logitem_ops);
439 	qf->qql_item.li_mountp = mp;
440 	qf->qql_start_lip = start;
441 	qf->qql_flags = flags;
442 	return qf;
443 }
444