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 */ 75 static inline void xfs_dqflock(xfs_dquot_t *dqp) 76 { 77 wait_for_completion(&dqp->q_flush); 78 } 79 80 static inline int xfs_dqflock_nowait(xfs_dquot_t *dqp) 81 { 82 return try_wait_for_completion(&dqp->q_flush); 83 } 84 85 static inline void xfs_dqfunlock(xfs_dquot_t *dqp) 86 { 87 complete(&dqp->q_flush); 88 } 89 90 static inline int xfs_dqlock_nowait(struct xfs_dquot *dqp) 91 { 92 return mutex_trylock(&dqp->q_qlock); 93 } 94 95 static inline void xfs_dqlock(struct xfs_dquot *dqp) 96 { 97 mutex_lock(&dqp->q_qlock); 98 } 99 100 static inline void xfs_dqunlock(struct xfs_dquot *dqp) 101 { 102 mutex_unlock(&dqp->q_qlock); 103 } 104 105 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 } 117 118 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(struct xfs_dquot *, struct xfs_buf **); 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 *); 155 156 static inline struct xfs_dquot *xfs_qm_dqhold(struct xfs_dquot *dqp) 157 { 158 xfs_dqlock(dqp); 159 dqp->q_nrefs++; 160 xfs_dqunlock(dqp); 161 return dqp; 162 } 163 164 extern const struct xfs_buf_ops xfs_dquot_buf_ops; 165 166 #endif /* __XFS_DQUOT_H__ */ 167