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
 20struct xfs_mount;
 21struct xfs_trans;
 22
 23enum {
 24	XFS_QLOWSP_1_PCNT = 0,
 25	XFS_QLOWSP_3_PCNT,
 26	XFS_QLOWSP_5_PCNT,
 27	XFS_QLOWSP_MAX
 28};
 29
 30struct xfs_dquot_res {
 31	/* Total resources allocated and reserved. */
 32	xfs_qcnt_t		reserved;
 33
 34	/* Total resources allocated. */
 35	xfs_qcnt_t		count;
 36
 37	/* Absolute and preferred limits. */
 38	xfs_qcnt_t		hardlimit;
 39	xfs_qcnt_t		softlimit;
 40
 41	/*
 42	 * For root dquots, this is the default grace period, in seconds.
 43	 * Otherwise, this is when the quota grace period expires,
 44	 * in seconds since the Unix epoch.
 45	 */
 46	time64_t		timer;
 47};
 48
 49static inline bool
 50xfs_dquot_res_over_limits(
 51	const struct xfs_dquot_res	*qres)
 52{
 53	if ((qres->softlimit && qres->softlimit < qres->reserved) ||
 54	    (qres->hardlimit && qres->hardlimit < qres->reserved))
 55		return true;
 56	return false;
 57}
 58
 59struct xfs_dquot_pre {
 60	xfs_qcnt_t		q_prealloc_lo_wmark;
 61	xfs_qcnt_t		q_prealloc_hi_wmark;
 62	int64_t			q_low_space[XFS_QLOWSP_MAX];
 63};
 64
 65/*
 66 * The incore dquot structure
 67 */
 68struct xfs_dquot {
 69	struct list_head	q_lru;
 70	struct xfs_mount	*q_mount;
 71	xfs_dqtype_t		q_type;
 72	uint16_t		q_flags;
 73	xfs_dqid_t		q_id;
 74	struct lockref		q_lockref;
 75	int			q_bufoffset;
 76	xfs_daddr_t		q_blkno;
 77	xfs_fileoff_t		q_fileoffset;
 78
 79	struct xfs_dquot_res	q_blk;	/* regular blocks */
 80	struct xfs_dquot_res	q_ino;	/* inodes */
 81	struct xfs_dquot_res	q_rtb;	/* realtime blocks */
 82
 83	struct xfs_dq_logitem	q_logitem;
 84
 85	struct xfs_dquot_pre	q_blk_prealloc;
 86	struct xfs_dquot_pre	q_rtb_prealloc;
 87
 88	struct mutex		q_qlock;
 89	struct completion	q_flush;
 90	atomic_t		q_pincount;
 91	struct wait_queue_head	q_pinwait;
 92};
 93
 94/*
 95 * Lock hierarchy for q_qlock:
 96 *	XFS_QLOCK_NORMAL is the implicit default,
 97 *	XFS_QLOCK_NESTED is the dquot with the higher id in xfs_dqlock2
 98 */
 99enum {
100	XFS_QLOCK_NORMAL = 0,
101	XFS_QLOCK_NESTED,
102};
103
104/*
105 * Manage the q_flush completion queue embedded in the dquot. This completion
106 * queue synchronizes processes attempting to flush the in-core dquot back to
107 * disk.
108 */
109static inline void xfs_dqflock(struct xfs_dquot *dqp)
110{
111	wait_for_completion(&dqp->q_flush);
112}
113
114static inline bool xfs_dqflock_nowait(struct xfs_dquot *dqp)
115{
116	return try_wait_for_completion(&dqp->q_flush);
117}
118
119static inline void xfs_dqfunlock(struct xfs_dquot *dqp)
120{
121	complete(&dqp->q_flush);
122}
123
124static inline int
125xfs_dquot_type(const struct xfs_dquot *dqp)
126{
127	return dqp->q_type & XFS_DQTYPE_REC_MASK;
128}
129
130static inline int xfs_this_quota_on(struct xfs_mount *mp, xfs_dqtype_t type)
131{
132	switch (type) {
133	case XFS_DQTYPE_USER:
134		return XFS_IS_UQUOTA_ON(mp);
135	case XFS_DQTYPE_GROUP:
136		return XFS_IS_GQUOTA_ON(mp);
137	case XFS_DQTYPE_PROJ:
138		return XFS_IS_PQUOTA_ON(mp);
139	default:
140		return 0;
141	}
142}
143
144static inline struct xfs_dquot *xfs_inode_dquot(
145	struct xfs_inode	*ip,
146	xfs_dqtype_t		type)
147{
148	if (xfs_is_metadir_inode(ip))
149		return NULL;
150
151	switch (type) {
152	case XFS_DQTYPE_USER:
153		return ip->i_udquot;
154	case XFS_DQTYPE_GROUP:
155		return ip->i_gdquot;
156	case XFS_DQTYPE_PROJ:
157		return ip->i_pdquot;
158	default:
159		return NULL;
160	}
161}
162
163/* Decide if the dquot's limits are actually being enforced. */
164static inline bool
165xfs_dquot_is_enforced(
166	const struct xfs_dquot	*dqp)
167{
168	switch (xfs_dquot_type(dqp)) {
169	case XFS_DQTYPE_USER:
170		return XFS_IS_UQUOTA_ENFORCED(dqp->q_mount);
171	case XFS_DQTYPE_GROUP:
172		return XFS_IS_GQUOTA_ENFORCED(dqp->q_mount);
173	case XFS_DQTYPE_PROJ:
174		return XFS_IS_PQUOTA_ENFORCED(dqp->q_mount);
175	}
176	ASSERT(0);
177	return false;
178}
179
180/*
181 * Check whether a dquot is under low free space conditions. We assume the quota
182 * is enabled and enforced.
183 */
184static inline bool xfs_dquot_lowsp(struct xfs_dquot *dqp)
185{
186	int64_t freesp;
187
188	freesp = dqp->q_blk.hardlimit - dqp->q_blk.reserved;
189	if (freesp < dqp->q_blk_prealloc.q_low_space[XFS_QLOWSP_1_PCNT])
190		return true;
191
192	freesp = dqp->q_rtb.hardlimit - dqp->q_rtb.reserved;
193	if (freesp < dqp->q_rtb_prealloc.q_low_space[XFS_QLOWSP_1_PCNT])
194		return true;
195
196	return false;
197}
198
199void xfs_dquot_to_disk(struct xfs_disk_dquot *ddqp, struct xfs_dquot *dqp);
200
201#define XFS_DQ_IS_LOCKED(dqp)	(mutex_is_locked(&((dqp)->q_qlock)))
202#define XFS_DQ_IS_DIRTY(dqp)	((dqp)->q_flags & XFS_DQFLAG_DIRTY)
203
204void		xfs_qm_dqdestroy(struct xfs_dquot *dqp);
205int		xfs_qm_dqflush(struct xfs_dquot *dqp, struct xfs_buf *bp);
206void		xfs_qm_dqunpin_wait(struct xfs_dquot *dqp);
207void		xfs_qm_adjust_dqtimers(struct xfs_dquot *d);
208void		xfs_qm_adjust_dqlimits(struct xfs_dquot *d);
209xfs_dqid_t	xfs_qm_id_for_quotatype(struct xfs_inode *ip,
210				xfs_dqtype_t type);
211int		xfs_qm_dqget(struct xfs_mount *mp, xfs_dqid_t id,
212				xfs_dqtype_t type, bool can_alloc,
213				struct xfs_dquot **dqpp);
214int		xfs_qm_dqget_inode(struct xfs_inode *ip, xfs_dqtype_t type,
215				bool can_alloc, struct xfs_dquot **dqpp);
216int		xfs_qm_dqget_next(struct xfs_mount *mp, xfs_dqid_t id,
217				xfs_dqtype_t type, struct xfs_dquot **dqpp);
218int		xfs_qm_dqget_uncached(struct xfs_mount *mp,
219				xfs_dqid_t id, xfs_dqtype_t type,
220				struct xfs_dquot **dqpp);
221
222void		xfs_dqlock2(struct xfs_dquot *, struct xfs_dquot *);
223void		xfs_dqlockn(struct xfs_dqtrx *q);
224
225void		xfs_dquot_set_prealloc_limits(struct xfs_dquot *);
226
227int xfs_dquot_attach_buf(struct xfs_trans *tp, struct xfs_dquot *dqp);
228int xfs_dquot_use_attached_buf(struct xfs_dquot *dqp, struct xfs_buf **bpp);
229void xfs_dquot_detach_buf(struct xfs_dquot *dqp);
230
231static inline struct xfs_dquot *xfs_qm_dqhold(struct xfs_dquot *dqp)
232{
233	lockref_get(&dqp->q_lockref);
234	return dqp;
235}
236
237time64_t xfs_dquot_set_timeout(struct xfs_mount *mp, time64_t timeout);
238time64_t xfs_dquot_set_grace_period(time64_t grace);
239
240void xfs_qm_init_dquot_blk(struct xfs_trans *tp, xfs_dqid_t id, xfs_dqtype_t
241		type, struct xfs_buf *bp);
242
243#endif /* __XFS_DQUOT_H__ */