1 /*
2 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it would be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
17 */
18 #ifndef __XFS_DQUOT_H__
19 #define __XFS_DQUOT_H__
20
21 /*
22 * Dquots are structures that hold quota information about a user or a group,
23 * much like inodes are for files. In fact, dquots share many characteristics
24 * with inodes. However, dquots can also be a centralized resource, relative
25 * to a collection of inodes. In this respect, dquots share some characteristics
26 * of the superblock.
27 * XFS dquots exploit both those in its algorithms. They make every attempt
28 * to not be a bottleneck when quotas are on and have minimal impact, if any,
29 * when quotas are off.
30 */
31
32 struct xfs_mount;
33 struct xfs_trans;
34
35 enum {
36 XFS_QLOWSP_1_PCNT = 0,
37 XFS_QLOWSP_3_PCNT,
38 XFS_QLOWSP_5_PCNT,
39 XFS_QLOWSP_MAX
40 };
41
42 /*
43 * The incore dquot structure
44 */
45 typedef struct xfs_dquot {
46 uint dq_flags; /* various flags (XFS_DQ_*) */
47 struct list_head q_lru; /* global free list of dquots */
48 struct xfs_mount*q_mount; /* filesystem this relates to */
49 struct xfs_trans*q_transp; /* trans this belongs to currently */
50 uint q_nrefs; /* # active refs from inodes */
51 xfs_daddr_t q_blkno; /* blkno of dquot buffer */
52 int q_bufoffset; /* off of dq in buffer (# dquots) */
53 xfs_fileoff_t q_fileoffset; /* offset in quotas file */
54
55 xfs_disk_dquot_t q_core; /* actual usage & quotas */
56 xfs_dq_logitem_t q_logitem; /* dquot log item */
57 xfs_qcnt_t q_res_bcount; /* total regular nblks used+reserved */
58 xfs_qcnt_t q_res_icount; /* total inos allocd+reserved */
59 xfs_qcnt_t q_res_rtbcount;/* total realtime blks used+reserved */
60 xfs_qcnt_t q_prealloc_lo_wmark;/* prealloc throttle wmark */
61 xfs_qcnt_t q_prealloc_hi_wmark;/* prealloc disabled wmark */
62 int64_t q_low_space[XFS_QLOWSP_MAX];
63 struct mutex q_qlock; /* quota lock */
64 struct completion q_flush; /* flush completion queue */
65 atomic_t q_pincount; /* dquot pin count */
66 wait_queue_head_t q_pinwait; /* dquot pinning wait queue */
67 } xfs_dquot_t;
68
69 /*
70 * Lock hierarchy for q_qlock:
71 * XFS_QLOCK_NORMAL is the implicit default,
72 * XFS_QLOCK_NESTED is the dquot with the higher id in xfs_dqlock2
73 */
74 enum {
75 XFS_QLOCK_NORMAL = 0,
76 XFS_QLOCK_NESTED,
77 };
78
79 /*
80 * Manage the q_flush completion queue embedded in the dquot. This completion
81 * queue synchronizes processes attempting to flush the in-core dquot back to
82 * disk.
83 */
xfs_dqflock(xfs_dquot_t * dqp)84 static inline void xfs_dqflock(xfs_dquot_t *dqp)
85 {
86 wait_for_completion(&dqp->q_flush);
87 }
88
xfs_dqflock_nowait(xfs_dquot_t * dqp)89 static inline bool xfs_dqflock_nowait(xfs_dquot_t *dqp)
90 {
91 return try_wait_for_completion(&dqp->q_flush);
92 }
93
xfs_dqfunlock(xfs_dquot_t * dqp)94 static inline void xfs_dqfunlock(xfs_dquot_t *dqp)
95 {
96 complete(&dqp->q_flush);
97 }
98
xfs_dqlock_nowait(struct xfs_dquot * dqp)99 static inline int xfs_dqlock_nowait(struct xfs_dquot *dqp)
100 {
101 return mutex_trylock(&dqp->q_qlock);
102 }
103
xfs_dqlock(struct xfs_dquot * dqp)104 static inline void xfs_dqlock(struct xfs_dquot *dqp)
105 {
106 mutex_lock(&dqp->q_qlock);
107 }
108
xfs_dqunlock(struct xfs_dquot * dqp)109 static inline void xfs_dqunlock(struct xfs_dquot *dqp)
110 {
111 mutex_unlock(&dqp->q_qlock);
112 }
113
xfs_this_quota_on(struct xfs_mount * mp,int type)114 static inline int xfs_this_quota_on(struct xfs_mount *mp, int type)
115 {
116 switch (type & XFS_DQ_ALLTYPES) {
117 case XFS_DQ_USER:
118 return XFS_IS_UQUOTA_ON(mp);
119 case XFS_DQ_GROUP:
120 return XFS_IS_GQUOTA_ON(mp);
121 case XFS_DQ_PROJ:
122 return XFS_IS_PQUOTA_ON(mp);
123 default:
124 return 0;
125 }
126 }
127
xfs_inode_dquot(struct xfs_inode * ip,int type)128 static inline xfs_dquot_t *xfs_inode_dquot(struct xfs_inode *ip, int type)
129 {
130 switch (type & XFS_DQ_ALLTYPES) {
131 case XFS_DQ_USER:
132 return ip->i_udquot;
133 case XFS_DQ_GROUP:
134 return ip->i_gdquot;
135 case XFS_DQ_PROJ:
136 return ip->i_pdquot;
137 default:
138 return NULL;
139 }
140 }
141
142 /*
143 * Check whether a dquot is under low free space conditions. We assume the quota
144 * is enabled and enforced.
145 */
xfs_dquot_lowsp(struct xfs_dquot * dqp)146 static inline bool xfs_dquot_lowsp(struct xfs_dquot *dqp)
147 {
148 int64_t freesp;
149
150 freesp = be64_to_cpu(dqp->q_core.d_blk_hardlimit) - dqp->q_res_bcount;
151 if (freesp < dqp->q_low_space[XFS_QLOWSP_1_PCNT])
152 return true;
153
154 return false;
155 }
156
157 #define XFS_DQ_IS_LOCKED(dqp) (mutex_is_locked(&((dqp)->q_qlock)))
158 #define XFS_DQ_IS_DIRTY(dqp) ((dqp)->dq_flags & XFS_DQ_DIRTY)
159 #define XFS_QM_ISUDQ(dqp) ((dqp)->dq_flags & XFS_DQ_USER)
160 #define XFS_QM_ISPDQ(dqp) ((dqp)->dq_flags & XFS_DQ_PROJ)
161 #define XFS_QM_ISGDQ(dqp) ((dqp)->dq_flags & XFS_DQ_GROUP)
162
163 extern int xfs_qm_dqread(struct xfs_mount *, xfs_dqid_t, uint,
164 uint, struct xfs_dquot **);
165 extern void xfs_qm_dqdestroy(xfs_dquot_t *);
166 extern int xfs_qm_dqflush(struct xfs_dquot *, struct xfs_buf **);
167 extern void xfs_qm_dqunpin_wait(xfs_dquot_t *);
168 extern void xfs_qm_adjust_dqtimers(xfs_mount_t *,
169 xfs_disk_dquot_t *);
170 extern void xfs_qm_adjust_dqlimits(struct xfs_mount *,
171 struct xfs_dquot *);
172 extern int xfs_qm_dqget(xfs_mount_t *, xfs_inode_t *,
173 xfs_dqid_t, uint, uint, xfs_dquot_t **);
174 extern void xfs_qm_dqput(xfs_dquot_t *);
175
176 extern void xfs_dqlock2(struct xfs_dquot *, struct xfs_dquot *);
177
178 extern void xfs_dquot_set_prealloc_limits(struct xfs_dquot *);
179
xfs_qm_dqhold(struct xfs_dquot * dqp)180 static inline struct xfs_dquot *xfs_qm_dqhold(struct xfs_dquot *dqp)
181 {
182 xfs_dqlock(dqp);
183 dqp->q_nrefs++;
184 xfs_dqunlock(dqp);
185 return dqp;
186 }
187
188 #endif /* __XFS_DQUOT_H__ */
189