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 /*
31 * The incore dquot structure
32 */
33 typedef struct xfs_dquot {
34 uint dq_flags; /* various flags (XFS_DQ_*) */
35 struct list_head q_lru; /* global free list of dquots */
36 struct xfs_mount*q_mount; /* filesystem this relates to */
37 uint q_nrefs; /* # active refs from inodes */
38 xfs_daddr_t q_blkno; /* blkno of dquot buffer */
39 int q_bufoffset; /* off of dq in buffer (# dquots) */
40 xfs_fileoff_t q_fileoffset; /* offset in quotas file */
41
42 xfs_disk_dquot_t q_core; /* actual usage & quotas */
43 xfs_dq_logitem_t q_logitem; /* dquot log item */
44 xfs_qcnt_t q_res_bcount; /* total regular nblks used+reserved */
45 xfs_qcnt_t q_res_icount; /* total inos allocd+reserved */
46 xfs_qcnt_t q_res_rtbcount;/* total realtime blks used+reserved */
47 xfs_qcnt_t q_prealloc_lo_wmark;/* prealloc throttle wmark */
48 xfs_qcnt_t q_prealloc_hi_wmark;/* prealloc disabled wmark */
49 int64_t q_low_space[XFS_QLOWSP_MAX];
50 struct mutex q_qlock; /* quota lock */
51 struct completion q_flush; /* flush completion queue */
52 atomic_t q_pincount; /* dquot pin count */
53 wait_queue_head_t q_pinwait; /* dquot pinning wait queue */
54 } xfs_dquot_t;
55
56 /*
57 * Lock hierarchy for q_qlock:
58 * XFS_QLOCK_NORMAL is the implicit default,
59 * XFS_QLOCK_NESTED is the dquot with the higher id in xfs_dqlock2
60 */
61 enum {
62 XFS_QLOCK_NORMAL = 0,
63 XFS_QLOCK_NESTED,
64 };
65
66 /*
67 * Manage the q_flush completion queue embedded in the dquot. This completion
68 * queue synchronizes processes attempting to flush the in-core dquot back to
69 * disk.
70 */
xfs_dqflock(xfs_dquot_t * dqp)71 static inline void xfs_dqflock(xfs_dquot_t *dqp)
72 {
73 wait_for_completion(&dqp->q_flush);
74 }
75
xfs_dqflock_nowait(xfs_dquot_t * dqp)76 static inline bool xfs_dqflock_nowait(xfs_dquot_t *dqp)
77 {
78 return try_wait_for_completion(&dqp->q_flush);
79 }
80
xfs_dqfunlock(xfs_dquot_t * dqp)81 static inline void xfs_dqfunlock(xfs_dquot_t *dqp)
82 {
83 complete(&dqp->q_flush);
84 }
85
xfs_dqlock_nowait(struct xfs_dquot * dqp)86 static inline int xfs_dqlock_nowait(struct xfs_dquot *dqp)
87 {
88 return mutex_trylock(&dqp->q_qlock);
89 }
90
xfs_dqlock(struct xfs_dquot * dqp)91 static inline void xfs_dqlock(struct xfs_dquot *dqp)
92 {
93 mutex_lock(&dqp->q_qlock);
94 }
95
xfs_dqunlock(struct xfs_dquot * dqp)96 static inline void xfs_dqunlock(struct xfs_dquot *dqp)
97 {
98 mutex_unlock(&dqp->q_qlock);
99 }
100
xfs_this_quota_on(struct xfs_mount * mp,int type)101 static inline int xfs_this_quota_on(struct xfs_mount *mp, int type)
102 {
103 switch (type & XFS_DQ_ALLTYPES) {
104 case XFS_DQ_USER:
105 return XFS_IS_UQUOTA_ON(mp);
106 case XFS_DQ_GROUP:
107 return XFS_IS_GQUOTA_ON(mp);
108 case XFS_DQ_PROJ:
109 return XFS_IS_PQUOTA_ON(mp);
110 default:
111 return 0;
112 }
113 }
114
xfs_inode_dquot(struct xfs_inode * ip,int type)115 static inline xfs_dquot_t *xfs_inode_dquot(struct xfs_inode *ip, int type)
116 {
117 switch (type & XFS_DQ_ALLTYPES) {
118 case XFS_DQ_USER:
119 return ip->i_udquot;
120 case XFS_DQ_GROUP:
121 return ip->i_gdquot;
122 case XFS_DQ_PROJ:
123 return ip->i_pdquot;
124 default:
125 return NULL;
126 }
127 }
128
129 /*
130 * Check whether a dquot is under low free space conditions. We assume the quota
131 * is enabled and enforced.
132 */
xfs_dquot_lowsp(struct xfs_dquot * dqp)133 static inline bool xfs_dquot_lowsp(struct xfs_dquot *dqp)
134 {
135 int64_t freesp;
136
137 freesp = be64_to_cpu(dqp->q_core.d_blk_hardlimit) - dqp->q_res_bcount;
138 if (freesp < dqp->q_low_space[XFS_QLOWSP_1_PCNT])
139 return true;
140
141 return false;
142 }
143
144 #define XFS_DQ_IS_LOCKED(dqp) (mutex_is_locked(&((dqp)->q_qlock)))
145 #define XFS_DQ_IS_DIRTY(dqp) ((dqp)->dq_flags & XFS_DQ_DIRTY)
146 #define XFS_QM_ISUDQ(dqp) ((dqp)->dq_flags & XFS_DQ_USER)
147 #define XFS_QM_ISPDQ(dqp) ((dqp)->dq_flags & XFS_DQ_PROJ)
148 #define XFS_QM_ISGDQ(dqp) ((dqp)->dq_flags & XFS_DQ_GROUP)
149
150 extern void xfs_qm_dqdestroy(xfs_dquot_t *);
151 extern int xfs_qm_dqflush(struct xfs_dquot *, struct xfs_buf **);
152 extern void xfs_qm_dqunpin_wait(xfs_dquot_t *);
153 extern void xfs_qm_adjust_dqtimers(xfs_mount_t *,
154 xfs_disk_dquot_t *);
155 extern void xfs_qm_adjust_dqlimits(struct xfs_mount *,
156 struct xfs_dquot *);
157 extern xfs_dqid_t xfs_qm_id_for_quotatype(struct xfs_inode *ip,
158 uint type);
159 extern int xfs_qm_dqget(struct xfs_mount *mp, xfs_dqid_t id,
160 uint type, bool can_alloc,
161 struct xfs_dquot **dqpp);
162 extern int xfs_qm_dqget_inode(struct xfs_inode *ip, uint type,
163 bool can_alloc,
164 struct xfs_dquot **dqpp);
165 extern int xfs_qm_dqget_next(struct xfs_mount *mp, xfs_dqid_t id,
166 uint type, struct xfs_dquot **dqpp);
167 extern int xfs_qm_dqget_uncached(struct xfs_mount *mp,
168 xfs_dqid_t id, uint type,
169 struct xfs_dquot **dqpp);
170 extern void xfs_qm_dqput(xfs_dquot_t *);
171
172 extern void xfs_dqlock2(struct xfs_dquot *, struct xfs_dquot *);
173
174 extern void xfs_dquot_set_prealloc_limits(struct xfs_dquot *);
175
xfs_qm_dqhold(struct xfs_dquot * dqp)176 static inline struct xfs_dquot *xfs_qm_dqhold(struct xfs_dquot *dqp)
177 {
178 xfs_dqlock(dqp);
179 dqp->q_nrefs++;
180 xfs_dqunlock(dqp);
181 return dqp;
182 }
183
184 typedef int (*xfs_qm_dqiterate_fn)(struct xfs_dquot *dq, uint dqtype,
185 void *priv);
186 int xfs_qm_dqiterate(struct xfs_mount *mp, uint dqtype,
187 xfs_qm_dqiterate_fn iter_fn, void *priv);
188
189 #endif /* __XFS_DQUOT_H__ */
190