1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
4 * All Rights Reserved.
5 */
6#ifndef __XFS_DQUOT_H__
7#define __XFS_DQUOT_H__
8
9/*
10 * Dquots are structures that hold quota information about a user or a group,
11 * much like inodes are for files. In fact, dquots share many characteristics
12 * with inodes. However, dquots can also be a centralized resource, relative
13 * to a collection of inodes. In this respect, dquots share some characteristics
14 * of the superblock.
15 * XFS dquots exploit both those in its algorithms. They make every attempt
16 * to not be a bottleneck when quotas are on and have minimal impact, if any,
17 * when quotas are off.
18 */
19
20struct xfs_mount;
21struct xfs_trans;
22
23enum {
24	XFS_QLOWSP_1_PCNT = 0,
25	XFS_QLOWSP_3_PCNT,
26	XFS_QLOWSP_5_PCNT,
27	XFS_QLOWSP_MAX
28};
29
30struct xfs_dquot_res {
31	/* Total resources allocated and reserved. */
32	xfs_qcnt_t		reserved;
33
34	/* Total resources allocated. */
35	xfs_qcnt_t		count;
36
37	/* Absolute and preferred limits. */
38	xfs_qcnt_t		hardlimit;
39	xfs_qcnt_t		softlimit;
40
41	/*
42	 * For root dquots, this is the default grace period, in seconds.
43	 * Otherwise, this is when the quota grace period expires,
44	 * in seconds since the Unix epoch.
45	 */
46	time64_t		timer;
47};
48
49static inline bool
50xfs_dquot_res_over_limits(
51	const struct xfs_dquot_res	*qres)
52{
53	if ((qres->softlimit && qres->softlimit < qres->reserved) ||
54	    (qres->hardlimit && qres->hardlimit < qres->reserved))
55		return true;
56	return false;
57}
58
59/*
60 * The incore dquot structure
61 */
62struct xfs_dquot {
63	struct list_head	q_lru;
64	struct xfs_mount	*q_mount;
65	xfs_dqtype_t		q_type;
66	uint16_t		q_flags;
67	xfs_dqid_t		q_id;
68	uint			q_nrefs;
69	int			q_bufoffset;
70	xfs_daddr_t		q_blkno;
71	xfs_fileoff_t		q_fileoffset;
72
73	struct xfs_dquot_res	q_blk;	/* regular blocks */
74	struct xfs_dquot_res	q_ino;	/* inodes */
75	struct xfs_dquot_res	q_rtb;	/* realtime blocks */
76
77	struct xfs_dq_logitem	q_logitem;
78
79	xfs_qcnt_t		q_prealloc_lo_wmark;
80	xfs_qcnt_t		q_prealloc_hi_wmark;
81	int64_t			q_low_space[XFS_QLOWSP_MAX];
82	struct mutex		q_qlock;
83	struct completion	q_flush;
84	atomic_t		q_pincount;
85	struct wait_queue_head	q_pinwait;
86};
87
88/*
89 * Lock hierarchy for q_qlock:
90 *	XFS_QLOCK_NORMAL is the implicit default,
91 *	XFS_QLOCK_NESTED is the dquot with the higher id in xfs_dqlock2
92 */
93enum {
94	XFS_QLOCK_NORMAL = 0,
95	XFS_QLOCK_NESTED,
96};
97
98/*
99 * Manage the q_flush completion queue embedded in the dquot. This completion
100 * queue synchronizes processes attempting to flush the in-core dquot back to
101 * disk.
102 */
103static inline void xfs_dqflock(struct xfs_dquot *dqp)
104{
105	wait_for_completion(&dqp->q_flush);
106}
107
108static inline bool xfs_dqflock_nowait(struct xfs_dquot *dqp)
109{
110	return try_wait_for_completion(&dqp->q_flush);
111}
112
113static inline void xfs_dqfunlock(struct xfs_dquot *dqp)
114{
115	complete(&dqp->q_flush);
116}
117
118static inline int xfs_dqlock_nowait(struct xfs_dquot *dqp)
119{
120	return mutex_trylock(&dqp->q_qlock);
121}
122
123static inline void xfs_dqlock(struct xfs_dquot *dqp)
124{
125	mutex_lock(&dqp->q_qlock);
126}
127
128static inline void xfs_dqunlock(struct xfs_dquot *dqp)
129{
130	mutex_unlock(&dqp->q_qlock);
131}
132
133static inline int
134xfs_dquot_type(const struct xfs_dquot *dqp)
135{
136	return dqp->q_type & XFS_DQTYPE_REC_MASK;
137}
138
139static inline int xfs_this_quota_on(struct xfs_mount *mp, xfs_dqtype_t type)
140{
141	switch (type) {
142	case XFS_DQTYPE_USER:
143		return XFS_IS_UQUOTA_ON(mp);
144	case XFS_DQTYPE_GROUP:
145		return XFS_IS_GQUOTA_ON(mp);
146	case XFS_DQTYPE_PROJ:
147		return XFS_IS_PQUOTA_ON(mp);
148	default:
149		return 0;
150	}
151}
152
153static inline struct xfs_dquot *xfs_inode_dquot(
154	struct xfs_inode	*ip,
155	xfs_dqtype_t		type)
156{
157	switch (type) {
158	case XFS_DQTYPE_USER:
159		return ip->i_udquot;
160	case XFS_DQTYPE_GROUP:
161		return ip->i_gdquot;
162	case XFS_DQTYPE_PROJ:
163		return ip->i_pdquot;
164	default:
165		return NULL;
166	}
167}
168
169/* Decide if the dquot's limits are actually being enforced. */
170static inline bool
171xfs_dquot_is_enforced(
172	const struct xfs_dquot	*dqp)
173{
174	switch (xfs_dquot_type(dqp)) {
175	case XFS_DQTYPE_USER:
176		return XFS_IS_UQUOTA_ENFORCED(dqp->q_mount);
177	case XFS_DQTYPE_GROUP:
178		return XFS_IS_GQUOTA_ENFORCED(dqp->q_mount);
179	case XFS_DQTYPE_PROJ:
180		return XFS_IS_PQUOTA_ENFORCED(dqp->q_mount);
181	}
182	ASSERT(0);
183	return false;
184}
185
186/*
187 * Check whether a dquot is under low free space conditions. We assume the quota
188 * is enabled and enforced.
189 */
190static inline bool xfs_dquot_lowsp(struct xfs_dquot *dqp)
191{
192	int64_t freesp;
193
194	freesp = dqp->q_blk.hardlimit - dqp->q_blk.reserved;
195	if (freesp < dqp->q_low_space[XFS_QLOWSP_1_PCNT])
196		return true;
197
198	return false;
199}
200
201void xfs_dquot_to_disk(struct xfs_disk_dquot *ddqp, struct xfs_dquot *dqp);
202
203#define XFS_DQ_IS_LOCKED(dqp)	(mutex_is_locked(&((dqp)->q_qlock)))
204#define XFS_DQ_IS_DIRTY(dqp)	((dqp)->q_flags & XFS_DQFLAG_DIRTY)
205
206void		xfs_qm_dqdestroy(struct xfs_dquot *dqp);
207int		xfs_qm_dqflush(struct xfs_dquot *dqp, struct xfs_buf **bpp);
208void		xfs_qm_dqunpin_wait(struct xfs_dquot *dqp);
209void		xfs_qm_adjust_dqtimers(struct xfs_dquot *d);
210void		xfs_qm_adjust_dqlimits(struct xfs_dquot *d);
211xfs_dqid_t	xfs_qm_id_for_quotatype(struct xfs_inode *ip,
212				xfs_dqtype_t type);
213int		xfs_qm_dqget(struct xfs_mount *mp, xfs_dqid_t id,
214				xfs_dqtype_t type, bool can_alloc,
215				struct xfs_dquot **dqpp);
216int		xfs_qm_dqget_inode(struct xfs_inode *ip, xfs_dqtype_t type,
217				bool can_alloc, struct xfs_dquot **dqpp);
218int		xfs_qm_dqget_next(struct xfs_mount *mp, xfs_dqid_t id,
219				xfs_dqtype_t type, struct xfs_dquot **dqpp);
220int		xfs_qm_dqget_uncached(struct xfs_mount *mp,
221				xfs_dqid_t id, xfs_dqtype_t type,
222				struct xfs_dquot **dqpp);
223void		xfs_qm_dqput(struct xfs_dquot *dqp);
224
225void		xfs_dqlock2(struct xfs_dquot *, struct xfs_dquot *);
226
227void		xfs_dquot_set_prealloc_limits(struct xfs_dquot *);
228
229static inline struct xfs_dquot *xfs_qm_dqhold(struct xfs_dquot *dqp)
230{
231	xfs_dqlock(dqp);
232	dqp->q_nrefs++;
233	xfs_dqunlock(dqp);
234	return dqp;
235}
236
237time64_t xfs_dquot_set_timeout(struct xfs_mount *mp, time64_t timeout);
238time64_t xfs_dquot_set_grace_period(time64_t grace);
239
240void xfs_qm_init_dquot_blk(struct xfs_trans *tp, xfs_dqid_t id, xfs_dqtype_t
241		type, struct xfs_buf *bp);
242
243#endif /* __XFS_DQUOT_H__ */
244