GNU Linux-libre 5.19-rc6-gnu
[releases.git] / fs / xfs / 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
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_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
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
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
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
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
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
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
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 }