fs/xfs/quota/xfs_dquot.h - maze/linux - Git at Google

 /*
  * Copyright (c) 2000-2005 Silicon Graphics, Inc.
  * All Rights Reserved.
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License as
  * published by the Free Software Foundation.
  *
  * This program is distributed in the hope that it would be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write the Free Software Foundation,
  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  */
 #ifndef __XFS_DQUOT_H__
 #define __XFS_DQUOT_H__

 /*
  * Dquots are structures that hold quota information about a user or a group,
  * much like inodes are for files. In fact, dquots share many characteristics
  * with inodes. However, dquots can also be a centralized resource, relative
  * to a collection of inodes. In this respect, dquots share some characteristics
  * of the superblock.
  * XFS dquots exploit both those in its algorithms. They make every attempt
  * to not be a bottleneck when quotas are on and have minimal impact, if any,
  * when quotas are off.
  */

 /*
  * The hash chain headers (hash buckets)
  */
 typedef struct xfs_dqhash {
 	struct xfs_dquot *qh_next;
 	mutex_t		  qh_lock;
 	uint		  qh_version;	/* ever increasing version */
 	uint		  qh_nelems;	/* number of dquots on the list */
 } xfs_dqhash_t;

 typedef struct xfs_dqlink {
 	struct xfs_dquot  *ql_next;	/* forward link */
 	struct xfs_dquot **ql_prevp;	/* pointer to prev ql_next */
 } xfs_dqlink_t;

 struct xfs_mount;
 struct xfs_trans;

 /*
  * This is the marker which is designed to occupy the first few
  * bytes of the xfs_dquot_t structure. Even inside this, the freelist pointers
  * must come first.
  * This serves as the marker ("sentinel") when we have to restart list
  * iterations because of locking considerations.
  */
 typedef struct xfs_dqmarker {
 	struct xfs_dquot*dqm_flnext;	/* link to freelist: must be first */
 	struct xfs_dquot*dqm_flprev;
 	xfs_dqlink_t	 dqm_mplist;	/* link to mount's list of dquots */
 	xfs_dqlink_t	 dqm_hashlist;	/* link to the hash chain */
 	uint		 dqm_flags;	/* various flags (XFS_DQ_*) */
 } xfs_dqmarker_t;

 /*
  * The incore dquot structure
  */
 typedef struct xfs_dquot {
 	xfs_dqmarker_t	 q_lists;	/* list ptrs, q_flags (marker) */
 	xfs_dqhash_t	*q_hash;	/* the hashchain header */
 	struct xfs_mount*q_mount;	/* filesystem this relates to */
 	struct xfs_trans*q_transp;	/* trans this belongs to currently */
 	uint		 q_nrefs;	/* # active refs from inodes */
 	xfs_daddr_t	 q_blkno;	/* blkno of dquot buffer */
 	int		 q_bufoffset;	/* off of dq in buffer (# dquots) */
 	xfs_fileoff_t	 q_fileoffset;	/* offset in quotas file */

 	struct xfs_dquot*q_gdquot;	/* group dquot, hint only */
 	xfs_disk_dquot_t q_core;	/* actual usage & quotas */
 	xfs_dq_logitem_t q_logitem;	/* dquot log item */
 	xfs_qcnt_t	 q_res_bcount;	/* total regular nblks used+reserved */
 	xfs_qcnt_t	 q_res_icount;	/* total inos allocd+reserved */
 	xfs_qcnt_t	 q_res_rtbcount;/* total realtime blks used+reserved */
 	mutex_t		 q_qlock;	/* quota lock */
 	sema_t		 q_flock;	/* flush lock */
 	uint		 q_pincount;	/* pin count for this dquot */
 	sv_t		 q_pinwait;	/* sync var for pinning */
 #ifdef XFS_DQUOT_TRACE
 	struct ktrace	*q_trace;	/* trace header structure */
 #endif
 } xfs_dquot_t;


 #define dq_flnext	q_lists.dqm_flnext
 #define dq_flprev	q_lists.dqm_flprev
 #define dq_mplist	q_lists.dqm_mplist
 #define dq_hashlist	q_lists.dqm_hashlist
 #define dq_flags	q_lists.dqm_flags

 #define XFS_DQHOLD(dqp)		((dqp)->q_nrefs++)

 #ifdef DEBUG
 static inline int
 XFS_DQ_IS_LOCKED(xfs_dquot_t *dqp)
 {
 	if (mutex_trylock(&dqp->q_qlock)) {
 		mutex_unlock(&dqp->q_qlock);
 		return 0;
 	}
 	return 1;
 }
 #endif


 /*
  * The following three routines simply manage the q_flock
  * semaphore embedded in the dquot.  This semaphore synchronizes
  * processes attempting to flush the in-core dquot back to disk.
  */
 #define xfs_dqflock(dqp)	 { psema(&((dqp)->q_flock), PINOD | PRECALC);\
 				   (dqp)->dq_flags |= XFS_DQ_FLOCKED; }
 #define xfs_dqfunlock(dqp)	 { ASSERT(issemalocked(&((dqp)->q_flock))); \
 				   vsema(&((dqp)->q_flock)); \
 				   (dqp)->dq_flags &= ~(XFS_DQ_FLOCKED); }

 #define XFS_DQ_PINLOCK(dqp)	   mutex_spinlock( \
 				     &(XFS_DQ_TO_QINF(dqp)->qi_pinlock))
 #define XFS_DQ_PINUNLOCK(dqp, s)   mutex_spinunlock( \
 				     &(XFS_DQ_TO_QINF(dqp)->qi_pinlock), s)

 #define XFS_DQ_IS_FLUSH_LOCKED(dqp) (issemalocked(&((dqp)->q_flock)))
 #define XFS_DQ_IS_ON_FREELIST(dqp)  ((dqp)->dq_flnext != (dqp))
 #define XFS_DQ_IS_DIRTY(dqp)	((dqp)->dq_flags & XFS_DQ_DIRTY)
 #define XFS_QM_ISUDQ(dqp)	((dqp)->dq_flags & XFS_DQ_USER)
 #define XFS_QM_ISPDQ(dqp)	((dqp)->dq_flags & XFS_DQ_PROJ)
 #define XFS_QM_ISGDQ(dqp)	((dqp)->dq_flags & XFS_DQ_GROUP)
 #define XFS_DQ_TO_QINF(dqp)	((dqp)->q_mount->m_quotainfo)
 #define XFS_DQ_TO_QIP(dqp)	(XFS_QM_ISUDQ(dqp) ? \
 				 XFS_DQ_TO_QINF(dqp)->qi_uquotaip : \
 				 XFS_DQ_TO_QINF(dqp)->qi_gquotaip)

 #define XFS_IS_THIS_QUOTA_OFF(d) (! (XFS_QM_ISUDQ(d) ? \
 				     (XFS_IS_UQUOTA_ON((d)->q_mount)) : \
 				     (XFS_IS_OQUOTA_ON((d)->q_mount))))

 #ifdef XFS_DQUOT_TRACE
 /*
  * Dquot Tracing stuff.
  */
 #define DQUOT_TRACE_SIZE	64
 #define DQUOT_KTRACE_ENTRY	1

 extern void		__xfs_dqtrace_entry(xfs_dquot_t *dqp, char *func,
 					    void *, xfs_inode_t *);
 #define xfs_dqtrace_entry_ino(a,b,ip) \
 		__xfs_dqtrace_entry((a), (b), (void*)__return_address, (ip))
 #define xfs_dqtrace_entry(a,b) \
 		__xfs_dqtrace_entry((a), (b), (void*)__return_address, NULL)
 #else
 #define xfs_dqtrace_entry(a,b)
 #define xfs_dqtrace_entry_ino(a,b,ip)
 #endif

 #ifdef QUOTADEBUG
 extern void		xfs_qm_dqprint(xfs_dquot_t *);
 #else
 #define xfs_qm_dqprint(a)
 #endif

 extern void		xfs_qm_dqdestroy(xfs_dquot_t *);
 extern int		xfs_qm_dqflush(xfs_dquot_t *, uint);
 extern int		xfs_qm_dqpurge(xfs_dquot_t *, uint);
 extern void		xfs_qm_dqunpin_wait(xfs_dquot_t *);
 extern int		xfs_qm_dqlock_nowait(xfs_dquot_t *);
 extern int		xfs_qm_dqflock_nowait(xfs_dquot_t *);
 extern void		xfs_qm_dqflock_pushbuf_wait(xfs_dquot_t *dqp);
 extern void		xfs_qm_adjust_dqtimers(xfs_mount_t *,
 					xfs_disk_dquot_t *);
 extern void		xfs_qm_adjust_dqlimits(xfs_mount_t *,
 					xfs_disk_dquot_t *);
 extern int		xfs_qm_dqget(xfs_mount_t *, xfs_inode_t *,
 					xfs_dqid_t, uint, uint, xfs_dquot_t **);
 extern void		xfs_qm_dqput(xfs_dquot_t *);
 extern void		xfs_qm_dqrele(xfs_dquot_t *);
 extern void		xfs_dqlock(xfs_dquot_t *);
 extern void		xfs_dqlock2(xfs_dquot_t *, xfs_dquot_t *);
 extern void		xfs_dqunlock(xfs_dquot_t *);
 extern void		xfs_dqunlock_nonotify(xfs_dquot_t *);

 #endif /* __XFS_DQUOT_H__ */
	/*
	* Copyright (c) 2000-2005 Silicon Graphics, Inc.
	* All Rights Reserved.
	*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public License as
	* published by the Free Software Foundation.
	*
	* This program is distributed in the hope that it would be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
	*/
	#ifndef __XFS_DQUOT_H__
	#define __XFS_DQUOT_H__

	/*
	* Dquots are structures that hold quota information about a user or a group,
	* much like inodes are for files. In fact, dquots share many characteristics
	* with inodes. However, dquots can also be a centralized resource, relative
	* to a collection of inodes. In this respect, dquots share some characteristics
	* of the superblock.
	* XFS dquots exploit both those in its algorithms. They make every attempt
	* to not be a bottleneck when quotas are on and have minimal impact, if any,
	* when quotas are off.
	*/

	/*
	* The hash chain headers (hash buckets)
	*/
	typedef struct xfs_dqhash {
	struct xfs_dquot *qh_next;
	mutex_t qh_lock;
	uint qh_version; /* ever increasing version */
	uint qh_nelems; /* number of dquots on the list */
	} xfs_dqhash_t;

	typedef struct xfs_dqlink {
	struct xfs_dquot ql_next; / forward link */
	struct xfs_dquot *ql_prevp; / pointer to prev ql_next */
	} xfs_dqlink_t;

	struct xfs_mount;
	struct xfs_trans;

	/*
	* This is the marker which is designed to occupy the first few
	* bytes of the xfs_dquot_t structure. Even inside this, the freelist pointers
	* must come first.
	* This serves as the marker ("sentinel") when we have to restart list
	* iterations because of locking considerations.
	*/
	typedef struct xfs_dqmarker {
	struct xfs_dquotdqm_flnext; / link to freelist: must be first */
	struct xfs_dquot*dqm_flprev;
	xfs_dqlink_t dqm_mplist; /* link to mount's list of dquots */
	xfs_dqlink_t dqm_hashlist; /* link to the hash chain */
	uint dqm_flags; /* various flags (XFS_DQ_) /
	} xfs_dqmarker_t;

	/*
	* The incore dquot structure
	*/
	typedef struct xfs_dquot {
	xfs_dqmarker_t q_lists; /* list ptrs, q_flags (marker) */
	xfs_dqhash_t q_hash; / the hashchain header */
	struct xfs_mountq_mount; / filesystem this relates to */
	struct xfs_transq_transp; / trans this belongs to currently */
	uint q_nrefs; /* # active refs from inodes */
	xfs_daddr_t q_blkno; /* blkno of dquot buffer */
	int q_bufoffset; /* off of dq in buffer (# dquots) */
	xfs_fileoff_t q_fileoffset; /* offset in quotas file */

	struct xfs_dquotq_gdquot; / group dquot, hint only */
	xfs_disk_dquot_t q_core; /* actual usage & quotas */
	xfs_dq_logitem_t q_logitem; /* dquot log item */
	xfs_qcnt_t q_res_bcount; /* total regular nblks used+reserved */
	xfs_qcnt_t q_res_icount; /* total inos allocd+reserved */
	xfs_qcnt_t q_res_rtbcount;/* total realtime blks used+reserved */
	mutex_t q_qlock; /* quota lock */
	sema_t q_flock; /* flush lock */
	uint q_pincount; /* pin count for this dquot */
	sv_t q_pinwait; /* sync var for pinning */
	#ifdef XFS_DQUOT_TRACE
	struct ktrace q_trace; / trace header structure */
	#endif
	} xfs_dquot_t;


	#define dq_flnext q_lists.dqm_flnext
	#define dq_flprev q_lists.dqm_flprev
	#define dq_mplist q_lists.dqm_mplist
	#define dq_hashlist q_lists.dqm_hashlist
	#define dq_flags q_lists.dqm_flags

	#define XFS_DQHOLD(dqp) ((dqp)->q_nrefs++)

	#ifdef DEBUG
	static inline int
	XFS_DQ_IS_LOCKED(xfs_dquot_t *dqp)
	{
	if (mutex_trylock(&dqp->q_qlock)) {
	mutex_unlock(&dqp->q_qlock);
	return 0;
	}
	return 1;
	}
	#endif


	/*
	* The following three routines simply manage the q_flock
	* semaphore embedded in the dquot. This semaphore synchronizes
	* processes attempting to flush the in-core dquot back to disk.
	*/
	#define xfs_dqflock(dqp) { psema(&((dqp)->q_flock), PINOD \| PRECALC);\
	(dqp)->dq_flags \|= XFS_DQ_FLOCKED; }
	#define xfs_dqfunlock(dqp) { ASSERT(issemalocked(&((dqp)->q_flock))); \
	vsema(&((dqp)->q_flock)); \
	(dqp)->dq_flags &= ~(XFS_DQ_FLOCKED); }

	#define XFS_DQ_PINLOCK(dqp) mutex_spinlock( \
	&(XFS_DQ_TO_QINF(dqp)->qi_pinlock))
	#define XFS_DQ_PINUNLOCK(dqp, s) mutex_spinunlock( \
	&(XFS_DQ_TO_QINF(dqp)->qi_pinlock), s)

	#define XFS_DQ_IS_FLUSH_LOCKED(dqp) (issemalocked(&((dqp)->q_flock)))
	#define XFS_DQ_IS_ON_FREELIST(dqp) ((dqp)->dq_flnext != (dqp))
	#define XFS_DQ_IS_DIRTY(dqp) ((dqp)->dq_flags & XFS_DQ_DIRTY)
	#define XFS_QM_ISUDQ(dqp) ((dqp)->dq_flags & XFS_DQ_USER)
	#define XFS_QM_ISPDQ(dqp) ((dqp)->dq_flags & XFS_DQ_PROJ)
	#define XFS_QM_ISGDQ(dqp) ((dqp)->dq_flags & XFS_DQ_GROUP)
	#define XFS_DQ_TO_QINF(dqp) ((dqp)->q_mount->m_quotainfo)
	#define XFS_DQ_TO_QIP(dqp) (XFS_QM_ISUDQ(dqp) ? \
	XFS_DQ_TO_QINF(dqp)->qi_uquotaip : \
	XFS_DQ_TO_QINF(dqp)->qi_gquotaip)

	#define XFS_IS_THIS_QUOTA_OFF(d) (! (XFS_QM_ISUDQ(d) ? \
	(XFS_IS_UQUOTA_ON((d)->q_mount)) : \
	(XFS_IS_OQUOTA_ON((d)->q_mount))))

	#ifdef XFS_DQUOT_TRACE
	/*
	* Dquot Tracing stuff.
	*/
	#define DQUOT_TRACE_SIZE 64
	#define DQUOT_KTRACE_ENTRY 1

	extern void __xfs_dqtrace_entry(xfs_dquot_t dqp, char func,
	void , xfs_inode_t );
	#define xfs_dqtrace_entry_ino(a,b,ip) \
	__xfs_dqtrace_entry((a), (b), (void*)__return_address, (ip))
	#define xfs_dqtrace_entry(a,b) \
	__xfs_dqtrace_entry((a), (b), (void*)__return_address, NULL)
	#else
	#define xfs_dqtrace_entry(a,b)
	#define xfs_dqtrace_entry_ino(a,b,ip)
	#endif

	#ifdef QUOTADEBUG
	extern void xfs_qm_dqprint(xfs_dquot_t *);
	#else
	#define xfs_qm_dqprint(a)
	#endif

	extern void xfs_qm_dqdestroy(xfs_dquot_t *);
	extern int xfs_qm_dqflush(xfs_dquot_t *, uint);
	extern int xfs_qm_dqpurge(xfs_dquot_t *, uint);
	extern void xfs_qm_dqunpin_wait(xfs_dquot_t *);
	extern int xfs_qm_dqlock_nowait(xfs_dquot_t *);
	extern int xfs_qm_dqflock_nowait(xfs_dquot_t *);
	extern void xfs_qm_dqflock_pushbuf_wait(xfs_dquot_t *dqp);
	extern void xfs_qm_adjust_dqtimers(xfs_mount_t *,
	xfs_disk_dquot_t *);
	extern void xfs_qm_adjust_dqlimits(xfs_mount_t *,
	xfs_disk_dquot_t *);
	extern int xfs_qm_dqget(xfs_mount_t , xfs_inode_t ,
	xfs_dqid_t, uint, uint, xfs_dquot_t **);
	extern void xfs_qm_dqput(xfs_dquot_t *);
	extern void xfs_qm_dqrele(xfs_dquot_t *);
	extern void xfs_dqlock(xfs_dquot_t *);
	extern void xfs_dqlock2(xfs_dquot_t , xfs_dquot_t );
	extern void xfs_dqunlock(xfs_dquot_t *);
	extern void xfs_dqunlock_nonotify(xfs_dquot_t *);

	#endif /* __XFS_DQUOT_H__ */