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 /*
36 * The incore dquot structure
37 */
38 typedef struct xfs_dquot {
39 uint dq_flags; /* various flags (XFS_DQ_*) */
40 struct list_head q_lru; /* global free list of dquots */
41 struct xfs_mount*q_mount; /* filesystem this relates to */
42 struct xfs_trans*q_transp; /* trans this belongs to currently */
43 uint q_nrefs; /* # active refs from inodes */
44 xfs_daddr_t q_blkno; /* blkno of dquot buffer */
45 int q_bufoffset; /* off of dq in buffer (# dquots) */
46 xfs_fileoff_t q_fileoffset; /* offset in quotas file */
47
48 struct xfs_dquot*q_gdquot; /* group dquot, hint only */
49 xfs_disk_dquot_t q_core; /* actual usage & quotas */
50 xfs_dq_logitem_t q_logitem; /* dquot log item */
51 xfs_qcnt_t q_res_bcount; /* total regular nblks used+reserved */
52 xfs_qcnt_t q_res_icount; /* total inos allocd+reserved */
53 xfs_qcnt_t q_res_rtbcount;/* total realtime blks used+reserved */
54 struct mutex q_qlock; /* quota lock */
55 struct completion q_flush; /* flush completion queue */
56 atomic_t q_pincount; /* dquot pin count */
57 wait_queue_head_t q_pinwait; /* dquot pinning wait queue */
58 } xfs_dquot_t;
59
60 /*
61 * Lock hierarchy for q_qlock:
62 * XFS_QLOCK_NORMAL is the implicit default,
63 * XFS_QLOCK_NESTED is the dquot with the higher id in xfs_dqlock2
64 */
65 enum {
66 XFS_QLOCK_NORMAL = 0,
67 XFS_QLOCK_NESTED,
68 };
69
70 /*
71 * Manage the q_flush completion queue embedded in the dquot. This completion
72 * queue synchronizes processes attempting to flush the in-core dquot back to
73 * disk.
74 */
xfs_dqflock(xfs_dquot_t * dqp)75 static inline void xfs_dqflock(xfs_dquot_t *dqp)
76 {
77 wait_for_completion(&dqp->q_flush);
78 }
79
xfs_dqflock_nowait(xfs_dquot_t * dqp)80 static inline int xfs_dqflock_nowait(xfs_dquot_t *dqp)
81 {
82 return try_wait_for_completion(&dqp->q_flush);
83 }
84
xfs_dqfunlock(xfs_dquot_t * dqp)85 static inline void xfs_dqfunlock(xfs_dquot_t *dqp)
86 {
87 complete(&dqp->q_flush);
88 }
89
xfs_dqlock_nowait(struct xfs_dquot * dqp)90 static inline int xfs_dqlock_nowait(struct xfs_dquot *dqp)
91 {
92 return mutex_trylock(&dqp->q_qlock);
93 }
94
xfs_dqlock(struct xfs_dquot * dqp)95 static inline void xfs_dqlock(struct xfs_dquot *dqp)
96 {
97 mutex_lock(&dqp->q_qlock);
98 }
99
xfs_dqunlock(struct xfs_dquot * dqp)100 static inline void xfs_dqunlock(struct xfs_dquot *dqp)
101 {
102 mutex_unlock(&dqp->q_qlock);
103 }
104
xfs_this_quota_on(struct xfs_mount * mp,int type)105 static inline int xfs_this_quota_on(struct xfs_mount *mp, int type)
106 {
107 switch (type & XFS_DQ_ALLTYPES) {
108 case XFS_DQ_USER:
109 return XFS_IS_UQUOTA_ON(mp);
110 case XFS_DQ_GROUP:
111 case XFS_DQ_PROJ:
112 return XFS_IS_OQUOTA_ON(mp);
113 default:
114 return 0;
115 }
116 }
117
xfs_inode_dquot(struct xfs_inode * ip,int type)118 static inline xfs_dquot_t *xfs_inode_dquot(struct xfs_inode *ip, int type)
119 {
120 switch (type & XFS_DQ_ALLTYPES) {
121 case XFS_DQ_USER:
122 return ip->i_udquot;
123 case XFS_DQ_GROUP:
124 case XFS_DQ_PROJ:
125 return ip->i_gdquot;
126 default:
127 return NULL;
128 }
129 }
130
131 #define XFS_DQ_IS_LOCKED(dqp) (mutex_is_locked(&((dqp)->q_qlock)))
132 #define XFS_DQ_IS_DIRTY(dqp) ((dqp)->dq_flags & XFS_DQ_DIRTY)
133 #define XFS_QM_ISUDQ(dqp) ((dqp)->dq_flags & XFS_DQ_USER)
134 #define XFS_QM_ISPDQ(dqp) ((dqp)->dq_flags & XFS_DQ_PROJ)
135 #define XFS_QM_ISGDQ(dqp) ((dqp)->dq_flags & XFS_DQ_GROUP)
136 #define XFS_DQ_TO_QINF(dqp) ((dqp)->q_mount->m_quotainfo)
137 #define XFS_DQ_TO_QIP(dqp) (XFS_QM_ISUDQ(dqp) ? \
138 XFS_DQ_TO_QINF(dqp)->qi_uquotaip : \
139 XFS_DQ_TO_QINF(dqp)->qi_gquotaip)
140
141 extern int xfs_qm_dqread(struct xfs_mount *, xfs_dqid_t, uint,
142 uint, struct xfs_dquot **);
143 extern void xfs_qm_dqdestroy(xfs_dquot_t *);
144 extern int xfs_qm_dqflush(xfs_dquot_t *, uint);
145 extern void xfs_qm_dqunpin_wait(xfs_dquot_t *);
146 extern void xfs_qm_adjust_dqtimers(xfs_mount_t *,
147 xfs_disk_dquot_t *);
148 extern void xfs_qm_adjust_dqlimits(xfs_mount_t *,
149 xfs_disk_dquot_t *);
150 extern int xfs_qm_dqget(xfs_mount_t *, xfs_inode_t *,
151 xfs_dqid_t, uint, uint, xfs_dquot_t **);
152 extern void xfs_qm_dqput(xfs_dquot_t *);
153
154 extern void xfs_dqlock2(struct xfs_dquot *, struct xfs_dquot *);
155 extern void xfs_dqflock_pushbuf_wait(struct xfs_dquot *dqp);
156
xfs_qm_dqhold(struct xfs_dquot * dqp)157 static inline struct xfs_dquot *xfs_qm_dqhold(struct xfs_dquot *dqp)
158 {
159 xfs_dqlock(dqp);
160 dqp->q_nrefs++;
161 xfs_dqunlock(dqp);
162 return dqp;
163 }
164
165 #endif /* __XFS_DQUOT_H__ */
166