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 /*
33 * The hash chain headers (hash buckets)
34 */
35 typedef struct xfs_dqhash {
36 struct list_head qh_list;
37 struct mutex qh_lock;
38 uint qh_version; /* ever increasing version */
39 uint qh_nelems; /* number of dquots on the list */
40 } xfs_dqhash_t;
41
42 struct xfs_mount;
43 struct xfs_trans;
44
45 /*
46 * The incore dquot structure
47 */
48 typedef struct xfs_dquot {
49 uint dq_flags; /* various flags (XFS_DQ_*) */
50 struct list_head q_freelist; /* global free list of dquots */
51 struct list_head q_mplist; /* mount's list of dquots */
52 struct list_head q_hashlist; /* gloabl hash list of dquots */
53 xfs_dqhash_t *q_hash; /* the hashchain header */
54 struct xfs_mount*q_mount; /* filesystem this relates to */
55 struct xfs_trans*q_transp; /* trans this belongs to currently */
56 uint q_nrefs; /* # active refs from inodes */
57 xfs_daddr_t q_blkno; /* blkno of dquot buffer */
58 int q_bufoffset; /* off of dq in buffer (# dquots) */
59 xfs_fileoff_t q_fileoffset; /* offset in quotas file */
60
61 struct xfs_dquot*q_gdquot; /* group dquot, hint only */
62 xfs_disk_dquot_t q_core; /* actual usage & quotas */
63 xfs_dq_logitem_t q_logitem; /* dquot log item */
64 xfs_qcnt_t q_res_bcount; /* total regular nblks used+reserved */
65 xfs_qcnt_t q_res_icount; /* total inos allocd+reserved */
66 xfs_qcnt_t q_res_rtbcount;/* total realtime blks used+reserved */
67 struct mutex q_qlock; /* quota lock */
68 struct completion q_flush; /* flush completion queue */
69 atomic_t q_pincount; /* dquot pin count */
70 wait_queue_head_t q_pinwait; /* dquot pinning wait queue */
71 } xfs_dquot_t;
72
73 /*
74 * Lock hierarchy for q_qlock:
75 * XFS_QLOCK_NORMAL is the implicit default,
76 * XFS_QLOCK_NESTED is the dquot with the higher id in xfs_dqlock2
77 */
78 enum {
79 XFS_QLOCK_NORMAL = 0,
80 XFS_QLOCK_NESTED,
81 };
82
83 #define XFS_DQHOLD(dqp) ((dqp)->q_nrefs++)
84
85 /*
86 * Manage the q_flush completion queue embedded in the dquot. This completion
87 * queue synchronizes processes attempting to flush the in-core dquot back to
88 * disk.
89 */
xfs_dqflock(xfs_dquot_t * dqp)90 static inline void xfs_dqflock(xfs_dquot_t *dqp)
91 {
92 wait_for_completion(&dqp->q_flush);
93 }
94
xfs_dqflock_nowait(xfs_dquot_t * dqp)95 static inline int xfs_dqflock_nowait(xfs_dquot_t *dqp)
96 {
97 return try_wait_for_completion(&dqp->q_flush);
98 }
99
xfs_dqfunlock(xfs_dquot_t * dqp)100 static inline void xfs_dqfunlock(xfs_dquot_t *dqp)
101 {
102 complete(&dqp->q_flush);
103 }
104
105 #define XFS_DQ_IS_LOCKED(dqp) (mutex_is_locked(&((dqp)->q_qlock)))
106 #define XFS_DQ_IS_DIRTY(dqp) ((dqp)->dq_flags & XFS_DQ_DIRTY)
107 #define XFS_QM_ISUDQ(dqp) ((dqp)->dq_flags & XFS_DQ_USER)
108 #define XFS_QM_ISPDQ(dqp) ((dqp)->dq_flags & XFS_DQ_PROJ)
109 #define XFS_QM_ISGDQ(dqp) ((dqp)->dq_flags & XFS_DQ_GROUP)
110 #define XFS_DQ_TO_QINF(dqp) ((dqp)->q_mount->m_quotainfo)
111 #define XFS_DQ_TO_QIP(dqp) (XFS_QM_ISUDQ(dqp) ? \
112 XFS_DQ_TO_QINF(dqp)->qi_uquotaip : \
113 XFS_DQ_TO_QINF(dqp)->qi_gquotaip)
114
115 #define XFS_IS_THIS_QUOTA_OFF(d) (! (XFS_QM_ISUDQ(d) ? \
116 (XFS_IS_UQUOTA_ON((d)->q_mount)) : \
117 (XFS_IS_OQUOTA_ON((d)->q_mount))))
118
119 #ifdef QUOTADEBUG
120 extern void xfs_qm_dqprint(xfs_dquot_t *);
121 #else
122 #define xfs_qm_dqprint(a)
123 #endif
124
125 extern void xfs_qm_dqdestroy(xfs_dquot_t *);
126 extern int xfs_qm_dqflush(xfs_dquot_t *, uint);
127 extern int xfs_qm_dqpurge(xfs_dquot_t *);
128 extern void xfs_qm_dqunpin_wait(xfs_dquot_t *);
129 extern int xfs_qm_dqlock_nowait(xfs_dquot_t *);
130 extern void xfs_qm_dqflock_pushbuf_wait(xfs_dquot_t *dqp);
131 extern void xfs_qm_adjust_dqtimers(xfs_mount_t *,
132 xfs_disk_dquot_t *);
133 extern void xfs_qm_adjust_dqlimits(xfs_mount_t *,
134 xfs_disk_dquot_t *);
135 extern int xfs_qm_dqget(xfs_mount_t *, xfs_inode_t *,
136 xfs_dqid_t, uint, uint, xfs_dquot_t **);
137 extern void xfs_qm_dqput(xfs_dquot_t *);
138 extern void xfs_dqlock(xfs_dquot_t *);
139 extern void xfs_dqlock2(xfs_dquot_t *, xfs_dquot_t *);
140 extern void xfs_dqunlock(xfs_dquot_t *);
141 extern void xfs_dqunlock_nonotify(xfs_dquot_t *);
142
143 #endif /* __XFS_DQUOT_H__ */
144