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 
20 struct xfs_mount;
21 struct xfs_trans;
22 
23 enum {
24 	XFS_QLOWSP_1_PCNT = 0,
25 	XFS_QLOWSP_3_PCNT,
26 	XFS_QLOWSP_5_PCNT,
27 	XFS_QLOWSP_MAX
28 };
29 
30 struct 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 static inline bool
xfs_dquot_res_over_limits(const struct xfs_dquot_res * qres)58 xfs_dquot_res_over_limits(
59 	const struct xfs_dquot_res	*qres)
60 {
61 	if ((qres->softlimit && qres->softlimit < qres->reserved) ||
62 	    (qres->hardlimit && qres->hardlimit < qres->reserved))
63 		return true;
64 	return false;
65 }
66 
67 /*
68  * The incore dquot structure
69  */
70 struct xfs_dquot {
71 	struct list_head	q_lru;
72 	struct xfs_mount	*q_mount;
73 	xfs_dqtype_t		q_type;
74 	uint16_t		q_flags;
75 	xfs_dqid_t		q_id;
76 	uint			q_nrefs;
77 	int			q_bufoffset;
78 	xfs_daddr_t		q_blkno;
79 	xfs_fileoff_t		q_fileoffset;
80 
81 	struct xfs_dquot_res	q_blk;	/* regular blocks */
82 	struct xfs_dquot_res	q_ino;	/* inodes */
83 	struct xfs_dquot_res	q_rtb;	/* realtime blocks */
84 
85 	struct xfs_dq_logitem	q_logitem;
86 
87 	xfs_qcnt_t		q_prealloc_lo_wmark;
88 	xfs_qcnt_t		q_prealloc_hi_wmark;
89 	int64_t			q_low_space[XFS_QLOWSP_MAX];
90 	struct mutex		q_qlock;
91 	struct completion	q_flush;
92 	atomic_t		q_pincount;
93 	struct wait_queue_head	q_pinwait;
94 };
95 
96 /*
97  * Lock hierarchy for q_qlock:
98  *	XFS_QLOCK_NORMAL is the implicit default,
99  *	XFS_QLOCK_NESTED is the dquot with the higher id in xfs_dqlock2
100  */
101 enum {
102 	XFS_QLOCK_NORMAL = 0,
103 	XFS_QLOCK_NESTED,
104 };
105 
106 /*
107  * Manage the q_flush completion queue embedded in the dquot. This completion
108  * queue synchronizes processes attempting to flush the in-core dquot back to
109  * disk.
110  */
xfs_dqflock(struct xfs_dquot * dqp)111 static inline void xfs_dqflock(struct xfs_dquot *dqp)
112 {
113 	wait_for_completion(&dqp->q_flush);
114 }
115 
xfs_dqflock_nowait(struct xfs_dquot * dqp)116 static inline bool xfs_dqflock_nowait(struct xfs_dquot *dqp)
117 {
118 	return try_wait_for_completion(&dqp->q_flush);
119 }
120 
xfs_dqfunlock(struct xfs_dquot * dqp)121 static inline void xfs_dqfunlock(struct xfs_dquot *dqp)
122 {
123 	complete(&dqp->q_flush);
124 }
125 
xfs_dqlock_nowait(struct xfs_dquot * dqp)126 static inline int xfs_dqlock_nowait(struct xfs_dquot *dqp)
127 {
128 	return mutex_trylock(&dqp->q_qlock);
129 }
130 
xfs_dqlock(struct xfs_dquot * dqp)131 static inline void xfs_dqlock(struct xfs_dquot *dqp)
132 {
133 	mutex_lock(&dqp->q_qlock);
134 }
135 
xfs_dqunlock(struct xfs_dquot * dqp)136 static inline void xfs_dqunlock(struct xfs_dquot *dqp)
137 {
138 	mutex_unlock(&dqp->q_qlock);
139 }
140 
141 static inline int
xfs_dquot_type(const struct xfs_dquot * dqp)142 xfs_dquot_type(const struct xfs_dquot *dqp)
143 {
144 	return dqp->q_type & XFS_DQTYPE_REC_MASK;
145 }
146 
xfs_this_quota_on(struct xfs_mount * mp,xfs_dqtype_t type)147 static inline int xfs_this_quota_on(struct xfs_mount *mp, xfs_dqtype_t type)
148 {
149 	switch (type) {
150 	case XFS_DQTYPE_USER:
151 		return XFS_IS_UQUOTA_ON(mp);
152 	case XFS_DQTYPE_GROUP:
153 		return XFS_IS_GQUOTA_ON(mp);
154 	case XFS_DQTYPE_PROJ:
155 		return XFS_IS_PQUOTA_ON(mp);
156 	default:
157 		return 0;
158 	}
159 }
160 
xfs_inode_dquot(struct xfs_inode * ip,xfs_dqtype_t type)161 static inline struct xfs_dquot *xfs_inode_dquot(
162 	struct xfs_inode	*ip,
163 	xfs_dqtype_t		type)
164 {
165 	switch (type) {
166 	case XFS_DQTYPE_USER:
167 		return ip->i_udquot;
168 	case XFS_DQTYPE_GROUP:
169 		return ip->i_gdquot;
170 	case XFS_DQTYPE_PROJ:
171 		return ip->i_pdquot;
172 	default:
173 		return NULL;
174 	}
175 }
176 
177 /* Decide if the dquot's limits are actually being enforced. */
178 static inline bool
xfs_dquot_is_enforced(const struct xfs_dquot * dqp)179 xfs_dquot_is_enforced(
180 	const struct xfs_dquot	*dqp)
181 {
182 	switch (xfs_dquot_type(dqp)) {
183 	case XFS_DQTYPE_USER:
184 		return XFS_IS_UQUOTA_ENFORCED(dqp->q_mount);
185 	case XFS_DQTYPE_GROUP:
186 		return XFS_IS_GQUOTA_ENFORCED(dqp->q_mount);
187 	case XFS_DQTYPE_PROJ:
188 		return XFS_IS_PQUOTA_ENFORCED(dqp->q_mount);
189 	}
190 	ASSERT(0);
191 	return false;
192 }
193 
194 /*
195  * Check whether a dquot is under low free space conditions. We assume the quota
196  * is enabled and enforced.
197  */
xfs_dquot_lowsp(struct xfs_dquot * dqp)198 static inline bool xfs_dquot_lowsp(struct xfs_dquot *dqp)
199 {
200 	int64_t freesp;
201 
202 	freesp = dqp->q_blk.hardlimit - dqp->q_blk.reserved;
203 	if (freesp < dqp->q_low_space[XFS_QLOWSP_1_PCNT])
204 		return true;
205 
206 	return false;
207 }
208 
209 void xfs_dquot_to_disk(struct xfs_disk_dquot *ddqp, struct xfs_dquot *dqp);
210 
211 #define XFS_DQ_IS_LOCKED(dqp)	(mutex_is_locked(&((dqp)->q_qlock)))
212 #define XFS_DQ_IS_DIRTY(dqp)	((dqp)->q_flags & XFS_DQFLAG_DIRTY)
213 
214 void		xfs_qm_dqdestroy(struct xfs_dquot *dqp);
215 int		xfs_qm_dqflush(struct xfs_dquot *dqp, struct xfs_buf **bpp);
216 void		xfs_qm_dqunpin_wait(struct xfs_dquot *dqp);
217 void		xfs_qm_adjust_dqtimers(struct xfs_dquot *d);
218 void		xfs_qm_adjust_dqlimits(struct xfs_dquot *d);
219 xfs_dqid_t	xfs_qm_id_for_quotatype(struct xfs_inode *ip,
220 				xfs_dqtype_t type);
221 int		xfs_qm_dqget(struct xfs_mount *mp, xfs_dqid_t id,
222 				xfs_dqtype_t type, bool can_alloc,
223 				struct xfs_dquot **dqpp);
224 int		xfs_qm_dqget_inode(struct xfs_inode *ip, xfs_dqtype_t type,
225 				bool can_alloc, struct xfs_dquot **dqpp);
226 int		xfs_qm_dqget_next(struct xfs_mount *mp, xfs_dqid_t id,
227 				xfs_dqtype_t type, struct xfs_dquot **dqpp);
228 int		xfs_qm_dqget_uncached(struct xfs_mount *mp,
229 				xfs_dqid_t id, xfs_dqtype_t type,
230 				struct xfs_dquot **dqpp);
231 void		xfs_qm_dqput(struct xfs_dquot *dqp);
232 
233 void		xfs_dqlock2(struct xfs_dquot *, struct xfs_dquot *);
234 
235 void		xfs_dquot_set_prealloc_limits(struct xfs_dquot *);
236 
xfs_qm_dqhold(struct xfs_dquot * dqp)237 static inline struct xfs_dquot *xfs_qm_dqhold(struct xfs_dquot *dqp)
238 {
239 	xfs_dqlock(dqp);
240 	dqp->q_nrefs++;
241 	xfs_dqunlock(dqp);
242 	return dqp;
243 }
244 
245 typedef int (*xfs_qm_dqiterate_fn)(struct xfs_dquot *dq,
246 		xfs_dqtype_t type, void *priv);
247 int xfs_qm_dqiterate(struct xfs_mount *mp, xfs_dqtype_t type,
248 		xfs_qm_dqiterate_fn iter_fn, void *priv);
249 
250 time64_t xfs_dquot_set_timeout(struct xfs_mount *mp, time64_t timeout);
251 time64_t xfs_dquot_set_grace_period(time64_t grace);
252 
253 #endif /* __XFS_DQUOT_H__ */
254