xref: /openbmc/linux/fs/xfs/xfs_dquot.h (revision 1edd0337)
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 static inline bool
50 xfs_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  */
62 struct 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  */
93 enum {
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  */
103 static inline void xfs_dqflock(struct xfs_dquot *dqp)
104 {
105 	wait_for_completion(&dqp->q_flush);
106 }
107 
108 static inline bool xfs_dqflock_nowait(struct xfs_dquot *dqp)
109 {
110 	return try_wait_for_completion(&dqp->q_flush);
111 }
112 
113 static inline void xfs_dqfunlock(struct xfs_dquot *dqp)
114 {
115 	complete(&dqp->q_flush);
116 }
117 
118 static inline int xfs_dqlock_nowait(struct xfs_dquot *dqp)
119 {
120 	return mutex_trylock(&dqp->q_qlock);
121 }
122 
123 static inline void xfs_dqlock(struct xfs_dquot *dqp)
124 {
125 	mutex_lock(&dqp->q_qlock);
126 }
127 
128 static inline void xfs_dqunlock(struct xfs_dquot *dqp)
129 {
130 	mutex_unlock(&dqp->q_qlock);
131 }
132 
133 static inline int
134 xfs_dquot_type(const struct xfs_dquot *dqp)
135 {
136 	return dqp->q_type & XFS_DQTYPE_REC_MASK;
137 }
138 
139 static 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 
153 static 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. */
170 static inline bool
171 xfs_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  */
190 static 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 
201 void 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 
206 void		xfs_qm_dqdestroy(struct xfs_dquot *dqp);
207 int		xfs_qm_dqflush(struct xfs_dquot *dqp, struct xfs_buf **bpp);
208 void		xfs_qm_dqunpin_wait(struct xfs_dquot *dqp);
209 void		xfs_qm_adjust_dqtimers(struct xfs_dquot *d);
210 void		xfs_qm_adjust_dqlimits(struct xfs_dquot *d);
211 xfs_dqid_t	xfs_qm_id_for_quotatype(struct xfs_inode *ip,
212 				xfs_dqtype_t type);
213 int		xfs_qm_dqget(struct xfs_mount *mp, xfs_dqid_t id,
214 				xfs_dqtype_t type, bool can_alloc,
215 				struct xfs_dquot **dqpp);
216 int		xfs_qm_dqget_inode(struct xfs_inode *ip, xfs_dqtype_t type,
217 				bool can_alloc, struct xfs_dquot **dqpp);
218 int		xfs_qm_dqget_next(struct xfs_mount *mp, xfs_dqid_t id,
219 				xfs_dqtype_t type, struct xfs_dquot **dqpp);
220 int		xfs_qm_dqget_uncached(struct xfs_mount *mp,
221 				xfs_dqid_t id, xfs_dqtype_t type,
222 				struct xfs_dquot **dqpp);
223 void		xfs_qm_dqput(struct xfs_dquot *dqp);
224 
225 void		xfs_dqlock2(struct xfs_dquot *, struct xfs_dquot *);
226 
227 void		xfs_dquot_set_prealloc_limits(struct xfs_dquot *);
228 
229 static 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 
237 typedef int (*xfs_qm_dqiterate_fn)(struct xfs_dquot *dq,
238 		xfs_dqtype_t type, void *priv);
239 int xfs_qm_dqiterate(struct xfs_mount *mp, xfs_dqtype_t type,
240 		xfs_qm_dqiterate_fn iter_fn, void *priv);
241 
242 time64_t xfs_dquot_set_timeout(struct xfs_mount *mp, time64_t timeout);
243 time64_t xfs_dquot_set_grace_period(time64_t grace);
244 
245 #endif /* __XFS_DQUOT_H__ */
246