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
DQUOT_ITEM(struct xfs_log_item * lip)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
xfs_qm_dquot_logitem_size(struct xfs_log_item * lip,int * nvecs,int * nbytes)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
xfs_qm_dquot_logitem_format(struct xfs_log_item * lip,struct xfs_log_vec * lv)44 xfs_qm_dquot_logitem_format(
45 struct xfs_log_item *lip,
46 struct xfs_log_vec *lv)
47 {
48 struct xfs_disk_dquot ddq;
49 struct xfs_dq_logitem *qlip = DQUOT_ITEM(lip);
50 struct xfs_log_iovec *vecp = NULL;
51 struct xfs_dq_logformat *qlf;
52
53 qlf = xlog_prepare_iovec(lv, &vecp, XLOG_REG_TYPE_QFORMAT);
54 qlf->qlf_type = XFS_LI_DQUOT;
55 qlf->qlf_size = 2;
56 qlf->qlf_id = qlip->qli_dquot->q_id;
57 qlf->qlf_blkno = qlip->qli_dquot->q_blkno;
58 qlf->qlf_len = 1;
59 qlf->qlf_boffset = qlip->qli_dquot->q_bufoffset;
60 xlog_finish_iovec(lv, vecp, sizeof(struct xfs_dq_logformat));
61
62 xfs_dquot_to_disk(&ddq, qlip->qli_dquot);
63
64 xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_DQUOT, &ddq,
65 sizeof(struct xfs_disk_dquot));
66 }
67
68 /*
69 * Increment the pin count of the given dquot.
70 */
71 STATIC void
xfs_qm_dquot_logitem_pin(struct xfs_log_item * lip)72 xfs_qm_dquot_logitem_pin(
73 struct xfs_log_item *lip)
74 {
75 struct xfs_dquot *dqp = DQUOT_ITEM(lip)->qli_dquot;
76
77 ASSERT(XFS_DQ_IS_LOCKED(dqp));
78 atomic_inc(&dqp->q_pincount);
79 }
80
81 /*
82 * Decrement the pin count of the given dquot, and wake up
83 * anyone in xfs_dqwait_unpin() if the count goes to 0. The
84 * dquot must have been previously pinned with a call to
85 * xfs_qm_dquot_logitem_pin().
86 */
87 STATIC void
xfs_qm_dquot_logitem_unpin(struct xfs_log_item * lip,int remove)88 xfs_qm_dquot_logitem_unpin(
89 struct xfs_log_item *lip,
90 int remove)
91 {
92 struct xfs_dquot *dqp = DQUOT_ITEM(lip)->qli_dquot;
93
94 ASSERT(atomic_read(&dqp->q_pincount) > 0);
95 if (atomic_dec_and_test(&dqp->q_pincount))
96 wake_up(&dqp->q_pinwait);
97 }
98
99 /*
100 * This is called to wait for the given dquot to be unpinned.
101 * Most of these pin/unpin routines are plagiarized from inode code.
102 */
103 void
xfs_qm_dqunpin_wait(struct xfs_dquot * dqp)104 xfs_qm_dqunpin_wait(
105 struct xfs_dquot *dqp)
106 {
107 ASSERT(XFS_DQ_IS_LOCKED(dqp));
108 if (atomic_read(&dqp->q_pincount) == 0)
109 return;
110
111 /*
112 * Give the log a push so we don't wait here too long.
113 */
114 xfs_log_force(dqp->q_mount, 0);
115 wait_event(dqp->q_pinwait, (atomic_read(&dqp->q_pincount) == 0));
116 }
117
118 STATIC uint
xfs_qm_dquot_logitem_push(struct xfs_log_item * lip,struct list_head * buffer_list)119 xfs_qm_dquot_logitem_push(
120 struct xfs_log_item *lip,
121 struct list_head *buffer_list)
122 __releases(&lip->li_ailp->ail_lock)
123 __acquires(&lip->li_ailp->ail_lock)
124 {
125 struct xfs_dquot *dqp = DQUOT_ITEM(lip)->qli_dquot;
126 struct xfs_buf *bp = lip->li_buf;
127 uint rval = XFS_ITEM_SUCCESS;
128 int error;
129
130 if (atomic_read(&dqp->q_pincount) > 0)
131 return XFS_ITEM_PINNED;
132
133 if (!xfs_dqlock_nowait(dqp))
134 return XFS_ITEM_LOCKED;
135
136 /*
137 * Re-check the pincount now that we stabilized the value by
138 * taking the quota lock.
139 */
140 if (atomic_read(&dqp->q_pincount) > 0) {
141 rval = XFS_ITEM_PINNED;
142 goto out_unlock;
143 }
144
145 /*
146 * Someone else is already flushing the dquot. Nothing we can do
147 * here but wait for the flush to finish and remove the item from
148 * the AIL.
149 */
150 if (!xfs_dqflock_nowait(dqp)) {
151 rval = XFS_ITEM_FLUSHING;
152 goto out_unlock;
153 }
154
155 spin_unlock(&lip->li_ailp->ail_lock);
156
157 error = xfs_qm_dqflush(dqp, &bp);
158 if (!error) {
159 if (!xfs_buf_delwri_queue(bp, buffer_list))
160 rval = XFS_ITEM_FLUSHING;
161 xfs_buf_relse(bp);
162 } else if (error == -EAGAIN)
163 rval = XFS_ITEM_LOCKED;
164
165 spin_lock(&lip->li_ailp->ail_lock);
166 out_unlock:
167 xfs_dqunlock(dqp);
168 return rval;
169 }
170
171 STATIC void
xfs_qm_dquot_logitem_release(struct xfs_log_item * lip)172 xfs_qm_dquot_logitem_release(
173 struct xfs_log_item *lip)
174 {
175 struct xfs_dquot *dqp = DQUOT_ITEM(lip)->qli_dquot;
176
177 ASSERT(XFS_DQ_IS_LOCKED(dqp));
178
179 /*
180 * dquots are never 'held' from getting unlocked at the end of
181 * a transaction. Their locking and unlocking is hidden inside the
182 * transaction layer, within trans_commit. Hence, no LI_HOLD flag
183 * for the logitem.
184 */
185 xfs_dqunlock(dqp);
186 }
187
188 STATIC void
xfs_qm_dquot_logitem_committing(struct xfs_log_item * lip,xfs_csn_t seq)189 xfs_qm_dquot_logitem_committing(
190 struct xfs_log_item *lip,
191 xfs_csn_t seq)
192 {
193 return xfs_qm_dquot_logitem_release(lip);
194 }
195
196 static const struct xfs_item_ops xfs_dquot_item_ops = {
197 .iop_size = xfs_qm_dquot_logitem_size,
198 .iop_format = xfs_qm_dquot_logitem_format,
199 .iop_pin = xfs_qm_dquot_logitem_pin,
200 .iop_unpin = xfs_qm_dquot_logitem_unpin,
201 .iop_release = xfs_qm_dquot_logitem_release,
202 .iop_committing = xfs_qm_dquot_logitem_committing,
203 .iop_push = xfs_qm_dquot_logitem_push,
204 };
205
206 /*
207 * Initialize the dquot log item for a newly allocated dquot.
208 * The dquot isn't locked at this point, but it isn't on any of the lists
209 * either, so we don't care.
210 */
211 void
xfs_qm_dquot_logitem_init(struct xfs_dquot * dqp)212 xfs_qm_dquot_logitem_init(
213 struct xfs_dquot *dqp)
214 {
215 struct xfs_dq_logitem *lp = &dqp->q_logitem;
216
217 xfs_log_item_init(dqp->q_mount, &lp->qli_item, XFS_LI_DQUOT,
218 &xfs_dquot_item_ops);
219 lp->qli_dquot = dqp;
220 }
221