| 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 | struct xfs_dquot*q_gdquot; /* group dquot, hint only */ |
| 56 | xfs_disk_dquot_t q_core; /* actual usage & quotas */ |
| 57 | xfs_dq_logitem_t q_logitem; /* dquot log item */ |
| 58 | xfs_qcnt_t q_res_bcount; /* total regular nblks used+reserved */ |
| 59 | xfs_qcnt_t q_res_icount; /* total inos allocd+reserved */ |
| 60 | xfs_qcnt_t q_res_rtbcount;/* total realtime blks used+reserved */ |
| 61 | xfs_qcnt_t q_prealloc_lo_wmark;/* prealloc throttle wmark */ |
| 62 | xfs_qcnt_t q_prealloc_hi_wmark;/* prealloc disabled wmark */ |
| 63 | int64_t q_low_space[XFS_QLOWSP_MAX]; |
| 64 | struct mutex q_qlock; /* quota lock */ |
| 65 | struct completion q_flush; /* flush completion queue */ |
| 66 | atomic_t q_pincount; /* dquot pin count */ |
| 67 | wait_queue_head_t q_pinwait; /* dquot pinning wait queue */ |
| 68 | } xfs_dquot_t; |
| 69 | |
| 70 | /* |
| 71 | * Lock hierarchy for q_qlock: |
| 72 | * XFS_QLOCK_NORMAL is the implicit default, |
| 73 | * XFS_QLOCK_NESTED is the dquot with the higher id in xfs_dqlock2 |
| 74 | */ |
| 75 | enum { |
| 76 | XFS_QLOCK_NORMAL = 0, |
| 77 | XFS_QLOCK_NESTED, |
| 78 | }; |
| 79 | |
| 80 | /* |
| 81 | * Manage the q_flush completion queue embedded in the dquot. This completion |
| 82 | * queue synchronizes processes attempting to flush the in-core dquot back to |
| 83 | * disk. |
| 84 | */ |
| 85 | static inline void xfs_dqflock(xfs_dquot_t *dqp) |
| 86 | { |
| 87 | wait_for_completion(&dqp->q_flush); |
| 88 | } |
| 89 | |
| 90 | static inline int xfs_dqflock_nowait(xfs_dquot_t *dqp) |
| 91 | { |
| 92 | return try_wait_for_completion(&dqp->q_flush); |
| 93 | } |
| 94 | |
| 95 | static inline void xfs_dqfunlock(xfs_dquot_t *dqp) |
| 96 | { |
| 97 | complete(&dqp->q_flush); |
| 98 | } |
| 99 | |
| 100 | static inline int xfs_dqlock_nowait(struct xfs_dquot *dqp) |
| 101 | { |
| 102 | return mutex_trylock(&dqp->q_qlock); |
| 103 | } |
| 104 | |
| 105 | static inline void xfs_dqlock(struct xfs_dquot *dqp) |
| 106 | { |
| 107 | mutex_lock(&dqp->q_qlock); |
| 108 | } |
| 109 | |
| 110 | static inline void xfs_dqunlock(struct xfs_dquot *dqp) |
| 111 | { |
| 112 | mutex_unlock(&dqp->q_qlock); |
| 113 | } |
| 114 | |
| 115 | static inline int xfs_this_quota_on(struct xfs_mount *mp, int type) |
| 116 | { |
| 117 | switch (type & XFS_DQ_ALLTYPES) { |
| 118 | case XFS_DQ_USER: |
| 119 | return XFS_IS_UQUOTA_ON(mp); |
| 120 | case XFS_DQ_GROUP: |
| 121 | case XFS_DQ_PROJ: |
| 122 | return XFS_IS_OQUOTA_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 | case XFS_DQ_PROJ: |
| 135 | return ip->i_gdquot; |
| 136 | default: |
| 137 | return NULL; |
| 138 | } |
| 139 | } |
| 140 | |
| 141 | #define XFS_DQ_IS_LOCKED(dqp) (mutex_is_locked(&((dqp)->q_qlock))) |
| 142 | #define XFS_DQ_IS_DIRTY(dqp) ((dqp)->dq_flags & XFS_DQ_DIRTY) |
| 143 | #define XFS_QM_ISUDQ(dqp) ((dqp)->dq_flags & XFS_DQ_USER) |
| 144 | #define XFS_QM_ISPDQ(dqp) ((dqp)->dq_flags & XFS_DQ_PROJ) |
| 145 | #define XFS_QM_ISGDQ(dqp) ((dqp)->dq_flags & XFS_DQ_GROUP) |
| 146 | |
| 147 | extern int xfs_qm_dqread(struct xfs_mount *, xfs_dqid_t, uint, |
| 148 | uint, struct xfs_dquot **); |
| 149 | extern void xfs_qm_dqdestroy(xfs_dquot_t *); |
| 150 | extern int xfs_qm_dqflush(struct xfs_dquot *, struct xfs_buf **); |
| 151 | extern void xfs_qm_dqunpin_wait(xfs_dquot_t *); |
| 152 | extern void xfs_qm_adjust_dqtimers(xfs_mount_t *, |
| 153 | xfs_disk_dquot_t *); |
| 154 | extern void xfs_qm_adjust_dqlimits(struct xfs_mount *, |
| 155 | struct xfs_dquot *); |
| 156 | extern int xfs_qm_dqget(xfs_mount_t *, xfs_inode_t *, |
| 157 | xfs_dqid_t, uint, uint, xfs_dquot_t **); |
| 158 | extern void xfs_qm_dqput(xfs_dquot_t *); |
| 159 | |
| 160 | extern void xfs_dqlock2(struct xfs_dquot *, struct xfs_dquot *); |
| 161 | |
| 162 | extern void xfs_dquot_set_prealloc_limits(struct xfs_dquot *); |
| 163 | |
| 164 | static inline struct xfs_dquot *xfs_qm_dqhold(struct xfs_dquot *dqp) |
| 165 | { |
| 166 | xfs_dqlock(dqp); |
| 167 | dqp->q_nrefs++; |
| 168 | xfs_dqunlock(dqp); |
| 169 | return dqp; |
| 170 | } |
| 171 | |
| 172 | extern const struct xfs_buf_ops xfs_dquot_buf_ops; |
| 173 | |
| 174 | #endif /* __XFS_DQUOT_H__ */ |