xref: /kernel/linux/linux-5.10/fs/xfs/xfs_dquot.h (revision 8c2ecf20)
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	/*
49	 * For root dquots, this is the maximum number of warnings that will
50	 * be issued for this quota type.  Otherwise, this is the number of
51	 * warnings issued against this quota.  Note that none of this is
52	 * implemented.
53	 */
54	xfs_qwarncnt_t		warnings;
55};
56
57/*
58 * The incore dquot structure
59 */
60struct xfs_dquot {
61	struct list_head	q_lru;
62	struct xfs_mount	*q_mount;
63	xfs_dqtype_t		q_type;
64	uint16_t		q_flags;
65	xfs_dqid_t		q_id;
66	uint			q_nrefs;
67	int			q_bufoffset;
68	xfs_daddr_t		q_blkno;
69	xfs_fileoff_t		q_fileoffset;
70
71	struct xfs_dquot_res	q_blk;	/* regular blocks */
72	struct xfs_dquot_res	q_ino;	/* inodes */
73	struct xfs_dquot_res	q_rtb;	/* realtime blocks */
74
75	struct xfs_dq_logitem	q_logitem;
76
77	xfs_qcnt_t		q_prealloc_lo_wmark;
78	xfs_qcnt_t		q_prealloc_hi_wmark;
79	int64_t			q_low_space[XFS_QLOWSP_MAX];
80	struct mutex		q_qlock;
81	struct completion	q_flush;
82	atomic_t		q_pincount;
83	struct wait_queue_head	q_pinwait;
84};
85
86/*
87 * Lock hierarchy for q_qlock:
88 *	XFS_QLOCK_NORMAL is the implicit default,
89 *	XFS_QLOCK_NESTED is the dquot with the higher id in xfs_dqlock2
90 */
91enum {
92	XFS_QLOCK_NORMAL = 0,
93	XFS_QLOCK_NESTED,
94};
95
96/*
97 * Manage the q_flush completion queue embedded in the dquot. This completion
98 * queue synchronizes processes attempting to flush the in-core dquot back to
99 * disk.
100 */
101static inline void xfs_dqflock(struct xfs_dquot *dqp)
102{
103	wait_for_completion(&dqp->q_flush);
104}
105
106static inline bool xfs_dqflock_nowait(struct xfs_dquot *dqp)
107{
108	return try_wait_for_completion(&dqp->q_flush);
109}
110
111static inline void xfs_dqfunlock(struct xfs_dquot *dqp)
112{
113	complete(&dqp->q_flush);
114}
115
116static inline int xfs_dqlock_nowait(struct xfs_dquot *dqp)
117{
118	return mutex_trylock(&dqp->q_qlock);
119}
120
121static inline void xfs_dqlock(struct xfs_dquot *dqp)
122{
123	mutex_lock(&dqp->q_qlock);
124}
125
126static inline void xfs_dqunlock(struct xfs_dquot *dqp)
127{
128	mutex_unlock(&dqp->q_qlock);
129}
130
131static inline int
132xfs_dquot_type(const struct xfs_dquot *dqp)
133{
134	return dqp->q_type & XFS_DQTYPE_REC_MASK;
135}
136
137static inline int xfs_this_quota_on(struct xfs_mount *mp, xfs_dqtype_t type)
138{
139	switch (type) {
140	case XFS_DQTYPE_USER:
141		return XFS_IS_UQUOTA_ON(mp);
142	case XFS_DQTYPE_GROUP:
143		return XFS_IS_GQUOTA_ON(mp);
144	case XFS_DQTYPE_PROJ:
145		return XFS_IS_PQUOTA_ON(mp);
146	default:
147		return 0;
148	}
149}
150
151static inline struct xfs_dquot *xfs_inode_dquot(
152	struct xfs_inode	*ip,
153	xfs_dqtype_t		type)
154{
155	switch (type) {
156	case XFS_DQTYPE_USER:
157		return ip->i_udquot;
158	case XFS_DQTYPE_GROUP:
159		return ip->i_gdquot;
160	case XFS_DQTYPE_PROJ:
161		return ip->i_pdquot;
162	default:
163		return NULL;
164	}
165}
166
167/* Decide if the dquot's limits are actually being enforced. */
168static inline bool
169xfs_dquot_is_enforced(
170	const struct xfs_dquot	*dqp)
171{
172	switch (xfs_dquot_type(dqp)) {
173	case XFS_DQTYPE_USER:
174		return XFS_IS_UQUOTA_ENFORCED(dqp->q_mount);
175	case XFS_DQTYPE_GROUP:
176		return XFS_IS_GQUOTA_ENFORCED(dqp->q_mount);
177	case XFS_DQTYPE_PROJ:
178		return XFS_IS_PQUOTA_ENFORCED(dqp->q_mount);
179	}
180	ASSERT(0);
181	return false;
182}
183
184/*
185 * Check whether a dquot is under low free space conditions. We assume the quota
186 * is enabled and enforced.
187 */
188static inline bool xfs_dquot_lowsp(struct xfs_dquot *dqp)
189{
190	int64_t freesp;
191
192	freesp = dqp->q_blk.hardlimit - dqp->q_blk.reserved;
193	if (freesp < dqp->q_low_space[XFS_QLOWSP_1_PCNT])
194		return true;
195
196	return false;
197}
198
199void xfs_dquot_to_disk(struct xfs_disk_dquot *ddqp, struct xfs_dquot *dqp);
200
201#define XFS_DQ_IS_LOCKED(dqp)	(mutex_is_locked(&((dqp)->q_qlock)))
202#define XFS_DQ_IS_DIRTY(dqp)	((dqp)->q_flags & XFS_DQFLAG_DIRTY)
203
204void		xfs_qm_dqdestroy(struct xfs_dquot *dqp);
205int		xfs_qm_dqflush(struct xfs_dquot *dqp, struct xfs_buf **bpp);
206void		xfs_qm_dqunpin_wait(struct xfs_dquot *dqp);
207void		xfs_qm_adjust_dqtimers(struct xfs_dquot *d);
208void		xfs_qm_adjust_dqlimits(struct xfs_dquot *d);
209xfs_dqid_t	xfs_qm_id_for_quotatype(struct xfs_inode *ip,
210				xfs_dqtype_t type);
211int		xfs_qm_dqget(struct xfs_mount *mp, xfs_dqid_t id,
212				xfs_dqtype_t type, bool can_alloc,
213				struct xfs_dquot **dqpp);
214int		xfs_qm_dqget_inode(struct xfs_inode *ip, xfs_dqtype_t type,
215				bool can_alloc, struct xfs_dquot **dqpp);
216int		xfs_qm_dqget_next(struct xfs_mount *mp, xfs_dqid_t id,
217				xfs_dqtype_t type, struct xfs_dquot **dqpp);
218int		xfs_qm_dqget_uncached(struct xfs_mount *mp,
219				xfs_dqid_t id, xfs_dqtype_t type,
220				struct xfs_dquot **dqpp);
221void		xfs_qm_dqput(struct xfs_dquot *dqp);
222
223void		xfs_dqlock2(struct xfs_dquot *, struct xfs_dquot *);
224
225void		xfs_dquot_set_prealloc_limits(struct xfs_dquot *);
226
227static inline struct xfs_dquot *xfs_qm_dqhold(struct xfs_dquot *dqp)
228{
229	xfs_dqlock(dqp);
230	dqp->q_nrefs++;
231	xfs_dqunlock(dqp);
232	return dqp;
233}
234
235typedef int (*xfs_qm_dqiterate_fn)(struct xfs_dquot *dq,
236		xfs_dqtype_t type, void *priv);
237int xfs_qm_dqiterate(struct xfs_mount *mp, xfs_dqtype_t type,
238		xfs_qm_dqiterate_fn iter_fn, void *priv);
239
240time64_t xfs_dquot_set_timeout(struct xfs_mount *mp, time64_t timeout);
241time64_t xfs_dquot_set_grace_period(time64_t grace);
242
243#endif /* __XFS_DQUOT_H__ */
244