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 */ 84 static inline void xfs_dqflock(xfs_dquot_t *dqp) 85 { 86 wait_for_completion(&dqp->q_flush); 87 } 88 89 static inline bool xfs_dqflock_nowait(xfs_dquot_t *dqp) 90 { 91 return try_wait_for_completion(&dqp->q_flush); 92 } 93 94 static inline void xfs_dqfunlock(xfs_dquot_t *dqp) 95 { 96 complete(&dqp->q_flush); 97 } 98 99 static inline int xfs_dqlock_nowait(struct xfs_dquot *dqp) 100 { 101 return mutex_trylock(&dqp->q_qlock); 102 } 103 104 static inline void xfs_dqlock(struct xfs_dquot *dqp) 105 { 106 mutex_lock(&dqp->q_qlock); 107 } 108 109 static inline void xfs_dqunlock(struct xfs_dquot *dqp) 110 { 111 mutex_unlock(&dqp->q_qlock); 112 } 113 114 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 } 127 128 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 */ 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 *); 179 180 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