fs/xfs/xfs_dquot.h

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (c) 2000-2005 Silicon Graphics, Inc.
   4  * All Rights Reserved.
   5  */
   6 #ifndef __XFS_DQUOT_H__
   7 #define __XFS_DQUOT_H__
   8
   9 /*
  10  * Dquots are structures that hold quota information about a user or a group,
  11  * much like inodes are for files. In fact, dquots share many characteristics
  12  * with inodes. However, dquots can also be a centralized resource, relative
  13  * to a collection of inodes. In this respect, dquots share some characteristics
  14  * of the superblock.
  15  * XFS dquots exploit both those in its algorithms. They make every attempt
  16  * to not be a bottleneck when quotas are on and have minimal impact, if any,
  17  * when quotas are off.
  18  */
  19
  20 struct xfs_mount;
  21 struct xfs_trans;
  22
  23 enum {
  24         XFS_QLOWSP_1_PCNT = 0,
  25         XFS_QLOWSP_3_PCNT,
  26         XFS_QLOWSP_5_PCNT,
  27         XFS_QLOWSP_MAX
  28 };
  29
  30 /*
  31  * The incore dquot structure
  32  */
  33 struct xfs_dquot {
  34         uint                    dq_flags;
  35         struct list_head        q_lru;
  36         struct xfs_mount        *q_mount;
  37         uint                    q_nrefs;
  38         xfs_daddr_t             q_blkno;
  39         int                     q_bufoffset;
  40         xfs_fileoff_t           q_fileoffset;
  41
  42         struct xfs_disk_dquot   q_core;
  43         struct xfs_dq_logitem   q_logitem;
  44         /* total regular nblks used+reserved */
  45         xfs_qcnt_t              q_res_bcount;
  46         /* total inos allocd+reserved */
  47         xfs_qcnt_t              q_res_icount;
  48         /* total realtime blks used+reserved */
  49         xfs_qcnt_t              q_res_rtbcount;
  50         xfs_qcnt_t              q_prealloc_lo_wmark;
  51         xfs_qcnt_t              q_prealloc_hi_wmark;
  52         int64_t                 q_low_space[XFS_QLOWSP_MAX];
  53         struct mutex            q_qlock;
  54         struct completion       q_flush;
  55         atomic_t                q_pincount;
  56         struct wait_queue_head  q_pinwait;
  57 };
  58
  59 /*
  60  * Lock hierarchy for q_qlock:
  61  *      XFS_QLOCK_NORMAL is the implicit default,
  62  *      XFS_QLOCK_NESTED is the dquot with the higher id in xfs_dqlock2
  63  */
  64 enum {
  65         XFS_QLOCK_NORMAL = 0,
  66         XFS_QLOCK_NESTED,
  67 };
  68
  69 /*
  70  * Manage the q_flush completion queue embedded in the dquot. This completion
  71  * queue synchronizes processes attempting to flush the in-core dquot back to
  72  * disk.
  73  */
  74 static inline void xfs_dqflock(struct xfs_dquot *dqp)
  75 {
  76         wait_for_completion(&dqp->q_flush);
  77 }
  78
  79 static inline bool xfs_dqflock_nowait(struct xfs_dquot *dqp)
  80 {
  81         return try_wait_for_completion(&dqp->q_flush);
  82 }
  83
  84 static inline void xfs_dqfunlock(struct xfs_dquot *dqp)
  85 {
  86         complete(&dqp->q_flush);
  87 }
  88
  89 static inline int xfs_dqlock_nowait(struct xfs_dquot *dqp)
  90 {
  91         return mutex_trylock(&dqp->q_qlock);
  92 }
  93
  94 static inline void xfs_dqlock(struct xfs_dquot *dqp)
  95 {
  96         mutex_lock(&dqp->q_qlock);
  97 }
  98
  99 static inline void xfs_dqunlock(struct xfs_dquot *dqp)
 100 {
 101         mutex_unlock(&dqp->q_qlock);
 102 }
 103
 104 static inline int xfs_this_quota_on(struct xfs_mount *mp, int type)
 105 {
 106         switch (type & XFS_DQ_ALLTYPES) {
 107         case XFS_DQ_USER:
 108                 return XFS_IS_UQUOTA_ON(mp);
 109         case XFS_DQ_GROUP:
 110                 return XFS_IS_GQUOTA_ON(mp);
 111         case XFS_DQ_PROJ:
 112                 return XFS_IS_PQUOTA_ON(mp);
 113         default:
 114                 return 0;
 115         }
 116 }
 117
 118 static inline struct xfs_dquot *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                 return ip->i_gdquot;
 125         case XFS_DQ_PROJ:
 126                 return ip->i_pdquot;
 127         default:
 128                 return NULL;
 129         }
 130 }
 131
 132 /*
 133  * Check whether a dquot is under low free space conditions. We assume the quota
 134  * is enabled and enforced.
 135  */
 136 static inline bool xfs_dquot_lowsp(struct xfs_dquot *dqp)
 137 {
 138         int64_t freesp;
 139
 140         freesp = be64_to_cpu(dqp->q_core.d_blk_hardlimit) - dqp->q_res_bcount;
 141         if (freesp < dqp->q_low_space[XFS_QLOWSP_1_PCNT])
 142                 return true;
 143
 144         return false;
 145 }
 146
 147 #define XFS_DQ_IS_LOCKED(dqp)   (mutex_is_locked(&((dqp)->q_qlock)))
 148 #define XFS_DQ_IS_DIRTY(dqp)    ((dqp)->dq_flags & XFS_DQ_DIRTY)
 149 #define XFS_QM_ISUDQ(dqp)       ((dqp)->dq_flags & XFS_DQ_USER)
 150 #define XFS_QM_ISPDQ(dqp)       ((dqp)->dq_flags & XFS_DQ_PROJ)
 151 #define XFS_QM_ISGDQ(dqp)       ((dqp)->dq_flags & XFS_DQ_GROUP)
 152
 153 void            xfs_qm_dqdestroy(struct xfs_dquot *dqp);
 154 int             xfs_qm_dqflush(struct xfs_dquot *dqp, struct xfs_buf **bpp);
 155 void            xfs_qm_dqunpin_wait(struct xfs_dquot *dqp);
 156 void            xfs_qm_adjust_dqtimers(struct xfs_mount *mp,
 157                                                 struct xfs_disk_dquot *d);
 158 void            xfs_qm_adjust_dqlimits(struct xfs_mount *mp,
 159                                                 struct xfs_dquot *d);
 160 xfs_dqid_t      xfs_qm_id_for_quotatype(struct xfs_inode *ip, uint type);
 161 int             xfs_qm_dqget(struct xfs_mount *mp, xfs_dqid_t id,
 162                                         uint type, bool can_alloc,
 163                                         struct xfs_dquot **dqpp);
 164 int             xfs_qm_dqget_inode(struct xfs_inode *ip, uint type,
 165                                                 bool can_alloc,
 166                                                 struct xfs_dquot **dqpp);
 167 int             xfs_qm_dqget_next(struct xfs_mount *mp, xfs_dqid_t id,
 168                                         uint type, struct xfs_dquot **dqpp);
 169 int             xfs_qm_dqget_uncached(struct xfs_mount *mp,
 170                                                 xfs_dqid_t id, uint type,
 171                                                 struct xfs_dquot **dqpp);
 172 void            xfs_qm_dqput(struct xfs_dquot *dqp);
 173
 174 void            xfs_dqlock2(struct xfs_dquot *, struct xfs_dquot *);
 175
 176 void            xfs_dquot_set_prealloc_limits(struct xfs_dquot *);
 177
 178 static inline struct xfs_dquot *xfs_qm_dqhold(struct xfs_dquot *dqp)
 179 {
 180         xfs_dqlock(dqp);
 181         dqp->q_nrefs++;
 182         xfs_dqunlock(dqp);
 183         return dqp;
 184 }
 185
 186 typedef int (*xfs_qm_dqiterate_fn)(struct xfs_dquot *dq, uint dqtype,
 187                 void *priv);
 188 int xfs_qm_dqiterate(struct xfs_mount *mp, uint dqtype,
 189                 xfs_qm_dqiterate_fn iter_fn, void *priv);
 190
 191 #endif /* __XFS_DQUOT_H__ */