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 /* 84 * Manage the q_flush completion queue embedded in the dquot. This completion 85 * queue synchronizes processes attempting to flush the in-core dquot back to 86 * disk. 87 */ 88 static inline void xfs_dqflock(xfs_dquot_t *dqp) 89 { 90 wait_for_completion(&dqp->q_flush); 91 } 92 93 static inline int xfs_dqflock_nowait(xfs_dquot_t *dqp) 94 { 95 return try_wait_for_completion(&dqp->q_flush); 96 } 97 98 static inline void xfs_dqfunlock(xfs_dquot_t *dqp) 99 { 100 complete(&dqp->q_flush); 101 } 102 103 static inline int xfs_dqlock_nowait(struct xfs_dquot *dqp) 104 { 105 return mutex_trylock(&dqp->q_qlock); 106 } 107 108 static inline void xfs_dqlock(struct xfs_dquot *dqp) 109 { 110 mutex_lock(&dqp->q_qlock); 111 } 112 113 static inline void xfs_dqunlock_nonotify(struct xfs_dquot *dqp) 114 { 115 mutex_unlock(&dqp->q_qlock); 116 } 117 118 #define XFS_DQ_IS_LOCKED(dqp) (mutex_is_locked(&((dqp)->q_qlock))) 119 #define XFS_DQ_IS_DIRTY(dqp) ((dqp)->dq_flags & XFS_DQ_DIRTY) 120 #define XFS_QM_ISUDQ(dqp) ((dqp)->dq_flags & XFS_DQ_USER) 121 #define XFS_QM_ISPDQ(dqp) ((dqp)->dq_flags & XFS_DQ_PROJ) 122 #define XFS_QM_ISGDQ(dqp) ((dqp)->dq_flags & XFS_DQ_GROUP) 123 #define XFS_DQ_TO_QINF(dqp) ((dqp)->q_mount->m_quotainfo) 124 #define XFS_DQ_TO_QIP(dqp) (XFS_QM_ISUDQ(dqp) ? \ 125 XFS_DQ_TO_QINF(dqp)->qi_uquotaip : \ 126 XFS_DQ_TO_QINF(dqp)->qi_gquotaip) 127 128 #define XFS_IS_THIS_QUOTA_OFF(d) (! (XFS_QM_ISUDQ(d) ? \ 129 (XFS_IS_UQUOTA_ON((d)->q_mount)) : \ 130 (XFS_IS_OQUOTA_ON((d)->q_mount)))) 131 132 extern int xfs_qm_dqread(struct xfs_mount *, xfs_dqid_t, uint, 133 uint, struct xfs_dquot **); 134 extern void xfs_qm_dqdestroy(xfs_dquot_t *); 135 extern int xfs_qm_dqflush(xfs_dquot_t *, uint); 136 extern void xfs_qm_dqpurge(xfs_dquot_t *); 137 extern void xfs_qm_dqunpin_wait(xfs_dquot_t *); 138 extern void xfs_qm_adjust_dqtimers(xfs_mount_t *, 139 xfs_disk_dquot_t *); 140 extern void xfs_qm_adjust_dqlimits(xfs_mount_t *, 141 xfs_disk_dquot_t *); 142 extern int xfs_qm_dqget(xfs_mount_t *, xfs_inode_t *, 143 xfs_dqid_t, uint, uint, xfs_dquot_t **); 144 extern void xfs_qm_dqput(xfs_dquot_t *); 145 146 extern void xfs_dqlock2(struct xfs_dquot *, struct xfs_dquot *); 147 extern void xfs_dqunlock(struct xfs_dquot *); 148 extern void xfs_dqflock_pushbuf_wait(struct xfs_dquot *dqp); 149 150 static inline struct xfs_dquot *xfs_qm_dqhold(struct xfs_dquot *dqp) 151 { 152 xfs_dqlock(dqp); 153 dqp->q_nrefs++; 154 xfs_dqunlock(dqp); 155 return dqp; 156 } 157 158 #endif /* __XFS_DQUOT_H__ */ 159