root/fs/xfs/xfs_dquot.h

INCLUDED FROM

DEFINITIONS

1. xfs_dqflock
2. xfs_dqflock_nowait
3. xfs_dqfunlock
4. xfs_dqlock_nowait
5. xfs_dqlock
6. xfs_dqunlock
7. xfs_this_quota_on
8. xfs_inode_dquot
9. xfs_dquot_lowsp
10. xfs_qm_dqhold

   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 typedef struct xfs_dquot {
  34         uint             dq_flags;      /* various flags (XFS_DQ_*) */
  35         struct list_head q_lru;         /* global free list of dquots */
  36         struct xfs_mount*q_mount;       /* filesystem this relates to */
  37         uint             q_nrefs;       /* # active refs from inodes */
  38         xfs_daddr_t      q_blkno;       /* blkno of dquot buffer */
  39         int              q_bufoffset;   /* off of dq in buffer (# dquots) */
  40         xfs_fileoff_t    q_fileoffset;  /* offset in quotas file */
  41 
  42         xfs_disk_dquot_t q_core;        /* actual usage & quotas */
  43         xfs_dq_logitem_t q_logitem;     /* dquot log item */
  44         xfs_qcnt_t       q_res_bcount;  /* total regular nblks used+reserved */
  45         xfs_qcnt_t       q_res_icount;  /* total inos allocd+reserved */
  46         xfs_qcnt_t       q_res_rtbcount;/* total realtime blks used+reserved */
  47         xfs_qcnt_t       q_prealloc_lo_wmark;/* prealloc throttle wmark */
  48         xfs_qcnt_t       q_prealloc_hi_wmark;/* prealloc disabled wmark */
  49         int64_t          q_low_space[XFS_QLOWSP_MAX];
  50         struct mutex     q_qlock;       /* quota lock */
  51         struct completion q_flush;      /* flush completion queue */
  52         atomic_t          q_pincount;   /* dquot pin count */
  53         wait_queue_head_t q_pinwait;    /* dquot pinning wait queue */
  54 } xfs_dquot_t;
  55 
  56 /*
  57  * Lock hierarchy for q_qlock:
  58  *      XFS_QLOCK_NORMAL is the implicit default,
  59  *      XFS_QLOCK_NESTED is the dquot with the higher id in xfs_dqlock2
  60  */
  61 enum {
  62         XFS_QLOCK_NORMAL = 0,
  63         XFS_QLOCK_NESTED,
  64 };
  65 
  66 /*
  67  * Manage the q_flush completion queue embedded in the dquot.  This completion
  68  * queue synchronizes processes attempting to flush the in-core dquot back to
  69  * disk.
  70  */
  71 static inline void xfs_dqflock(xfs_dquot_t *dqp)
  72 {
  73         wait_for_completion(&dqp->q_flush);
  74 }
  75 
  76 static inline bool xfs_dqflock_nowait(xfs_dquot_t *dqp)
  77 {
  78         return try_wait_for_completion(&dqp->q_flush);
  79 }
  80 
  81 static inline void xfs_dqfunlock(xfs_dquot_t *dqp)
  82 {
  83         complete(&dqp->q_flush);
  84 }
  85 
  86 static inline int xfs_dqlock_nowait(struct xfs_dquot *dqp)
  87 {
  88         return mutex_trylock(&dqp->q_qlock);
  89 }
  90 
  91 static inline void xfs_dqlock(struct xfs_dquot *dqp)
  92 {
  93         mutex_lock(&dqp->q_qlock);
  94 }
  95 
  96 static inline void xfs_dqunlock(struct xfs_dquot *dqp)
  97 {
  98         mutex_unlock(&dqp->q_qlock);
  99 }
 100 
 101 static inline int xfs_this_quota_on(struct xfs_mount *mp, int type)
 102 {
 103         switch (type & XFS_DQ_ALLTYPES) {
 104         case XFS_DQ_USER:
 105                 return XFS_IS_UQUOTA_ON(mp);
 106         case XFS_DQ_GROUP:
 107                 return XFS_IS_GQUOTA_ON(mp);
 108         case XFS_DQ_PROJ:
 109                 return XFS_IS_PQUOTA_ON(mp);
 110         default:
 111                 return 0;
 112         }
 113 }
 114 
 115 static inline xfs_dquot_t *xfs_inode_dquot(struct xfs_inode *ip, int type)
 116 {
 117         switch (type & XFS_DQ_ALLTYPES) {
 118         case XFS_DQ_USER:
 119                 return ip->i_udquot;
 120         case XFS_DQ_GROUP:
 121                 return ip->i_gdquot;
 122         case XFS_DQ_PROJ:
 123                 return ip->i_pdquot;
 124         default:
 125                 return NULL;
 126         }
 127 }
 128 
 129 /*
 130  * Check whether a dquot is under low free space conditions. We assume the quota
 131  * is enabled and enforced.
 132  */
 133 static inline bool xfs_dquot_lowsp(struct xfs_dquot *dqp)
 134 {
 135         int64_t freesp;
 136 
 137         freesp = be64_to_cpu(dqp->q_core.d_blk_hardlimit) - dqp->q_res_bcount;
 138         if (freesp < dqp->q_low_space[XFS_QLOWSP_1_PCNT])
 139                 return true;
 140 
 141         return false;
 142 }
 143 
 144 #define XFS_DQ_IS_LOCKED(dqp)   (mutex_is_locked(&((dqp)->q_qlock)))
 145 #define XFS_DQ_IS_DIRTY(dqp)    ((dqp)->dq_flags & XFS_DQ_DIRTY)
 146 #define XFS_QM_ISUDQ(dqp)       ((dqp)->dq_flags & XFS_DQ_USER)
 147 #define XFS_QM_ISPDQ(dqp)       ((dqp)->dq_flags & XFS_DQ_PROJ)
 148 #define XFS_QM_ISGDQ(dqp)       ((dqp)->dq_flags & XFS_DQ_GROUP)
 149 
 150 extern void             xfs_qm_dqdestroy(xfs_dquot_t *);
 151 extern int              xfs_qm_dqflush(struct xfs_dquot *, struct xfs_buf **);
 152 extern void             xfs_qm_dqunpin_wait(xfs_dquot_t *);
 153 extern void             xfs_qm_adjust_dqtimers(xfs_mount_t *,
 154                                         xfs_disk_dquot_t *);
 155 extern void             xfs_qm_adjust_dqlimits(struct xfs_mount *,
 156                                                struct xfs_dquot *);
 157 extern xfs_dqid_t       xfs_qm_id_for_quotatype(struct xfs_inode *ip,
 158                                         uint type);
 159 extern int              xfs_qm_dqget(struct xfs_mount *mp, xfs_dqid_t id,
 160                                         uint type, bool can_alloc,
 161                                         struct xfs_dquot **dqpp);
 162 extern int              xfs_qm_dqget_inode(struct xfs_inode *ip, uint type,
 163                                         bool can_alloc,
 164                                         struct xfs_dquot **dqpp);
 165 extern int              xfs_qm_dqget_next(struct xfs_mount *mp, xfs_dqid_t id,
 166                                         uint type, struct xfs_dquot **dqpp);
 167 extern int              xfs_qm_dqget_uncached(struct xfs_mount *mp,
 168                                         xfs_dqid_t id, uint type,
 169                                         struct xfs_dquot **dqpp);
 170 extern void             xfs_qm_dqput(xfs_dquot_t *);
 171 
 172 extern void             xfs_dqlock2(struct xfs_dquot *, struct xfs_dquot *);
 173 
 174 extern void             xfs_dquot_set_prealloc_limits(struct xfs_dquot *);
 175 
 176 static inline struct xfs_dquot *xfs_qm_dqhold(struct xfs_dquot *dqp)
 177 {
 178         xfs_dqlock(dqp);
 179         dqp->q_nrefs++;
 180         xfs_dqunlock(dqp);
 181         return dqp;
 182 }
 183 
 184 typedef int (*xfs_qm_dqiterate_fn)(struct xfs_dquot *dq, uint dqtype,
 185                 void *priv);
 186 int xfs_qm_dqiterate(struct xfs_mount *mp, uint dqtype,
 187                 xfs_qm_dqiterate_fn iter_fn, void *priv);
 188 
 189 #endif /* __XFS_DQUOT_H__ */