xfs_dquot_item.c

  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_shared.h"
  9#include "xfs_format.h"
 10#include "xfs_log_format.h"
 11#include "xfs_trans_resv.h"
 12#include "xfs_mount.h"
 13#include "xfs_inode.h"
 14#include "xfs_quota.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#include "xfs_error.h"
 21
 22static inline struct xfs_dq_logitem *DQUOT_ITEM(struct xfs_log_item *lip)
 23{
 24	return container_of(lip, struct xfs_dq_logitem, qli_item);
 25}
 26
 27/*
 28 * returns the number of iovecs needed to log the given dquot item.
 29 */
 30STATIC void
 31xfs_qm_dquot_logitem_size(
 32	struct xfs_log_item	*lip,
 33	int			*nvecs,
 34	int			*nbytes)
 35{
 36	*nvecs += 2;
 37	*nbytes += sizeof(struct xfs_dq_logformat) +
 38		   sizeof(struct xfs_disk_dquot);
 39}
 40
 41/*
 42 * fills in the vector of log iovecs for the given dquot log item.
 43 */
 44STATIC void
 45xfs_qm_dquot_logitem_format(
 46	struct xfs_log_item	*lip,
 47	struct xfs_log_vec	*lv)
 48{
 49	struct xfs_disk_dquot	ddq;
 50	struct xfs_dq_logitem	*qlip = DQUOT_ITEM(lip);
 51	struct xfs_log_iovec	*vecp = NULL;
 52	struct xfs_dq_logformat	*qlf;
 53
 54	qlf = xlog_prepare_iovec(lv, &vecp, XLOG_REG_TYPE_QFORMAT);
 55	qlf->qlf_type = XFS_LI_DQUOT;
 56	qlf->qlf_size = 2;
 57	qlf->qlf_id = qlip->qli_dquot->q_id;
 58	qlf->qlf_blkno = qlip->qli_dquot->q_blkno;
 59	qlf->qlf_len = 1;
 60	qlf->qlf_boffset = qlip->qli_dquot->q_bufoffset;
 61	xlog_finish_iovec(lv, vecp, sizeof(struct xfs_dq_logformat));
 62
 63	xfs_dquot_to_disk(&ddq, qlip->qli_dquot);
 64
 65	xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_DQUOT, &ddq,
 66			sizeof(struct xfs_disk_dquot));
 67}
 68
 69/*
 70 * Increment the pin count of the given dquot.
 71 */
 72STATIC void
 73xfs_qm_dquot_logitem_pin(
 74	struct xfs_log_item	*lip)
 75{
 76	struct xfs_dquot	*dqp = DQUOT_ITEM(lip)->qli_dquot;
 77
 78	ASSERT(XFS_DQ_IS_LOCKED(dqp));
 79	atomic_inc(&dqp->q_pincount);
 80}
 81
 82/*
 83 * Decrement the pin count of the given dquot, and wake up
 84 * anyone in xfs_dqwait_unpin() if the count goes to 0.	 The
 85 * dquot must have been previously pinned with a call to
 86 * xfs_qm_dquot_logitem_pin().
 87 */
 88STATIC void
 89xfs_qm_dquot_logitem_unpin(
 90	struct xfs_log_item	*lip,
 91	int			remove)
 92{
 93	struct xfs_dquot	*dqp = DQUOT_ITEM(lip)->qli_dquot;
 94
 95	ASSERT(atomic_read(&dqp->q_pincount) > 0);
 96	if (atomic_dec_and_test(&dqp->q_pincount))
 97		wake_up(&dqp->q_pinwait);
 98}
 99
100/*
101 * This is called to wait for the given dquot to be unpinned.
102 * Most of these pin/unpin routines are plagiarized from inode code.
103 */
104void
105xfs_qm_dqunpin_wait(
106	struct xfs_dquot	*dqp)
107{
108	ASSERT(XFS_DQ_IS_LOCKED(dqp));
109	if (atomic_read(&dqp->q_pincount) == 0)
110		return;
111
112	/*
113	 * Give the log a push so we don't wait here too long.
114	 */
115	xfs_log_force(dqp->q_mount, 0);
116	wait_event(dqp->q_pinwait, (atomic_read(&dqp->q_pincount) == 0));
117}
118
119STATIC uint
120xfs_qm_dquot_logitem_push(
121	struct xfs_log_item	*lip,
122	struct list_head	*buffer_list)
123		__releases(&lip->li_ailp->ail_lock)
124		__acquires(&lip->li_ailp->ail_lock)
125{
126	struct xfs_dq_logitem	*qlip = DQUOT_ITEM(lip);
127	struct xfs_dquot	*dqp = qlip->qli_dquot;
128	struct xfs_buf		*bp;
129	struct xfs_ail		*ailp = lip->li_ailp;
130	uint			rval = XFS_ITEM_SUCCESS;
131	int			error;
132
133	if (atomic_read(&dqp->q_pincount) > 0)
134		return XFS_ITEM_PINNED;
135
136	if (!mutex_trylock(&dqp->q_qlock))
137		return XFS_ITEM_LOCKED;
138
139	/*
140	 * Re-check the pincount now that we stabilized the value by
141	 * taking the quota lock.
142	 */
143	if (atomic_read(&dqp->q_pincount) > 0) {
144		rval = XFS_ITEM_PINNED;
145		goto out_unlock;
146	}
147
148	/*
149	 * Someone else is already flushing the dquot.  Nothing we can do
150	 * here but wait for the flush to finish and remove the item from
151	 * the AIL.
152	 */
153	if (!xfs_dqflock_nowait(dqp)) {
154		rval = XFS_ITEM_FLUSHING;
155		goto out_unlock;
156	}
157
158	spin_unlock(&ailp->ail_lock);
159
160	error = xfs_dquot_use_attached_buf(dqp, &bp);
161	if (error == -EAGAIN) {
162		xfs_dqfunlock(dqp);
163		rval = XFS_ITEM_LOCKED;
164		goto out_relock_ail;
165	}
166
167	/*
168	 * dqflush completes dqflock on error, and the delwri ioend does it on
169	 * success.
170	 */
171	error = xfs_qm_dqflush(dqp, bp);
172	if (!error) {
173		if (!xfs_buf_delwri_queue(bp, buffer_list))
174			rval = XFS_ITEM_FLUSHING;
175	}
176	xfs_buf_relse(bp);
177	/*
178	 * The buffer no longer protects the log item from reclaim, so
179	 * do not reference lip after this point.
180	 */
181
182out_relock_ail:
183	spin_lock(&ailp->ail_lock);
184out_unlock:
185	mutex_unlock(&dqp->q_qlock);
186	return rval;
187}
188
189STATIC void
190xfs_qm_dquot_logitem_release(
191	struct xfs_log_item	*lip)
192{
193	struct xfs_dquot	*dqp = DQUOT_ITEM(lip)->qli_dquot;
194
195	ASSERT(XFS_DQ_IS_LOCKED(dqp));
196
197	/*
198	 * dquots are never 'held' from getting unlocked at the end of
199	 * a transaction.  Their locking and unlocking is hidden inside the
200	 * transaction layer, within trans_commit. Hence, no LI_HOLD flag
201	 * for the logitem.
202	 */
203	mutex_unlock(&dqp->q_qlock);
204}
205
206STATIC void
207xfs_qm_dquot_logitem_committing(
208	struct xfs_log_item	*lip,
209	xfs_csn_t		seq)
210{
211	return xfs_qm_dquot_logitem_release(lip);
212}
213
214#ifdef DEBUG_EXPENSIVE
215static void
216xfs_qm_dquot_logitem_precommit_check(
217	struct xfs_dquot	*dqp)
218{
219	struct xfs_mount	*mp = dqp->q_mount;
220	struct xfs_disk_dquot	ddq = { };
221	xfs_failaddr_t		fa;
222
223	xfs_dquot_to_disk(&ddq, dqp);
224	fa = xfs_dquot_verify(mp, &ddq, dqp->q_id);
225	if (fa) {
226		XFS_CORRUPTION_ERROR("Bad dquot during logging",
227				XFS_ERRLEVEL_LOW, mp, &ddq, sizeof(ddq));
228		xfs_alert(mp,
229 "Metadata corruption detected at %pS, dquot 0x%x",
230				fa, dqp->q_id);
231		xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
232		ASSERT(fa == NULL);
233	}
234}
235#else
236# define xfs_qm_dquot_logitem_precommit_check(...)	((void)0)
237#endif
238
239static int
240xfs_qm_dquot_logitem_precommit(
241	struct xfs_trans	*tp,
242	struct xfs_log_item	*lip)
243{
244	struct xfs_dq_logitem	*qlip = DQUOT_ITEM(lip);
245	struct xfs_dquot	*dqp = qlip->qli_dquot;
246
247	xfs_qm_dquot_logitem_precommit_check(dqp);
248
249	return xfs_dquot_attach_buf(tp, dqp);
250}
251
252static const struct xfs_item_ops xfs_dquot_item_ops = {
253	.iop_size	= xfs_qm_dquot_logitem_size,
254	.iop_precommit	= xfs_qm_dquot_logitem_precommit,
255	.iop_format	= xfs_qm_dquot_logitem_format,
256	.iop_pin	= xfs_qm_dquot_logitem_pin,
257	.iop_unpin	= xfs_qm_dquot_logitem_unpin,
258	.iop_release	= xfs_qm_dquot_logitem_release,
259	.iop_committing	= xfs_qm_dquot_logitem_committing,
260	.iop_push	= xfs_qm_dquot_logitem_push,
261};
262
263/*
264 * Initialize the dquot log item for a newly allocated dquot.
265 * The dquot isn't locked at this point, but it isn't on any of the lists
266 * either, so we don't care.
267 */
268void
269xfs_qm_dquot_logitem_init(
270	struct xfs_dquot	*dqp)
271{
272	struct xfs_dq_logitem	*lp = &dqp->q_logitem;
273
274	xfs_log_item_init(dqp->q_mount, &lp->qli_item, XFS_LI_DQUOT,
275					&xfs_dquot_item_ops);
276	spin_lock_init(&lp->qli_lock);
277	lp->qli_dquot = dqp;
278	lp->qli_dirty = false;
279}