xfs: convert the per-mount dquot list to use list heads

Convert the dquot list on the filesytesm to use listhead
infrastructure rather than the roll-your-own in the quota code.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>

fs/xfs/quota/xfs_dquot.c

@@ -121,8 +121,9 @@ xfs_qm_dqinit(
 		 */
 		 dqp->q_nrefs = 0;
 		 dqp->q_blkno = 0;
-		 dqp->MPL_NEXT = dqp->HL_NEXT = NULL;
-		 dqp->HL_PREVP = dqp->MPL_PREVP = NULL;
+		 INIT_LIST_HEAD(&dqp->q_mplist);
+		 dqp->HL_NEXT = NULL;
+		 dqp->HL_PREVP = NULL;
 		 dqp->q_bufoffset = 0;
 		 dqp->q_fileoffset = 0;
 		 dqp->q_transp = NULL;
@@ -772,7 +773,7 @@ xfs_qm_dqlookup(
 			/*
 			 * All in core dquots must be on the dqlist of mp
 			 */
-			ASSERT(dqp->MPL_PREVP != NULL);
+			ASSERT(!list_empty(&dqp->q_mplist));
 
 			xfs_dqlock(dqp);
 			if (dqp->q_nrefs == 0) {
@@ -1039,7 +1040,7 @@ xfs_qm_dqget(
 	 * Attach this dquot to this filesystem's list of all dquots,
 	 * kept inside the mount structure in m_quotainfo field
 	 */
-	xfs_qm_mplist_lock(mp);
+	mutex_lock(&mp->m_quotainfo->qi_dqlist_lock);
 
 	/*
 	 * We return a locked dquot to the caller, with a reference taken
@@ -1047,9 +1048,9 @@ xfs_qm_dqget(
 	xfs_dqlock(dqp);
 	dqp->q_nrefs = 1;
 
-	XQM_MPLIST_INSERT(&(XFS_QI_MPL_LIST(mp)), dqp);
-
-	xfs_qm_mplist_unlock(mp);
+	list_add(&dqp->q_mplist, &mp->m_quotainfo->qi_dqlist);
+	mp->m_quotainfo->qi_dquots++;
+	mutex_unlock(&mp->m_quotainfo->qi_dqlist_lock);
 	mutex_unlock(&h->qh_lock);
  dqret:
 	ASSERT((ip == NULL) || xfs_isilocked(ip, XFS_ILOCK_EXCL));
@@ -1389,7 +1390,7 @@ xfs_qm_dqpurge(
 	xfs_dqhash_t	*thishash;
 	xfs_mount_t	*mp = dqp->q_mount;
 
-	ASSERT(XFS_QM_IS_MPLIST_LOCKED(mp));
+	ASSERT(mutex_is_locked(&mp->m_quotainfo->qi_dqlist_lock));
 	ASSERT(mutex_is_locked(&dqp->q_hash->qh_lock));
 
 	xfs_dqlock(dqp);
@@ -1454,7 +1455,9 @@ xfs_qm_dqpurge(
 
 	thishash = dqp->q_hash;
 	XQM_HASHLIST_REMOVE(thishash, dqp);
-	XQM_MPLIST_REMOVE(&(XFS_QI_MPL_LIST(mp)), dqp);
+	list_del_init(&dqp->q_mplist);
+	mp->m_quotainfo->qi_dqreclaims++;
+	mp->m_quotainfo->qi_dquots--;
 	/*
 	 * XXX Move this to the front of the freelist, if we can get the
 	 * freelist lock.

fs/xfs/quota/xfs_dquot.h

@@ -57,7 +57,6 @@ struct xfs_trans;
 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;
@@ -67,6 +66,7 @@ typedef struct xfs_dqmarker {
  */
 typedef struct xfs_dquot {
 	xfs_dqmarker_t	 q_lists;	/* list ptrs, q_flags (marker) */
+	struct list_head q_mplist;	/* mount's list of dquots */
 	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 */

fs/xfs/quota/xfs_qm.h

@@ -106,7 +106,9 @@ typedef struct xfs_qm {
 typedef struct xfs_quotainfo {
 	xfs_inode_t	*qi_uquotaip;	 /* user quota inode */
 	xfs_inode_t	*qi_gquotaip;	 /* group quota inode */
-	xfs_dqlist_t	 qi_dqlist;	 /* all dquots in filesys */
+	struct list_head qi_dqlist;	 /* all dquots in filesys */
+	struct mutex	 qi_dqlist_lock;
+	int		 qi_dquots;
 	int		 qi_dqreclaims;	 /* a change here indicates
 					    a removal in the dqlist */
 	time_t		 qi_btimelimit;	 /* limit for blks timer */

fs/xfs/quota/xfs_qm_syscalls.c

@@ -442,7 +442,7 @@ xfs_qm_scall_getqstat(
 			IRELE(gip);
 	}
 	if (mp->m_quotainfo) {
-		out->qs_incoredqs = XFS_QI_MPLNDQUOTS(mp);
+		out->qs_incoredqs = mp->m_quotainfo->qi_dquots;
 		out->qs_btimelimit = XFS_QI_BTIMELIMIT(mp);
 		out->qs_itimelimit = XFS_QI_ITIMELIMIT(mp);
 		out->qs_rtbtimelimit = XFS_QI_RTBTIMELIMIT(mp);

fs/xfs/quota/xfs_quota_priv.h

@@ -29,7 +29,6 @@
 
 #define XFS_DQ_IS_ADDEDTO_TRX(t, d)	((d)->q_transp == (t))
 
-#define XFS_QI_MPLRECLAIMS(mp)	((mp)->m_quotainfo->qi_dqreclaims)
 #define XFS_QI_UQIP(mp)		((mp)->m_quotainfo->qi_uquotaip)
 #define XFS_QI_GQIP(mp)		((mp)->m_quotainfo->qi_gquotaip)
 #define XFS_QI_DQCHUNKLEN(mp)	((mp)->m_quotainfo->qi_dqchunklen)
@@ -41,19 +40,6 @@
 #define XFS_QI_IWARNLIMIT(mp)	((mp)->m_quotainfo->qi_iwarnlimit)
 #define XFS_QI_QOFFLOCK(mp)	((mp)->m_quotainfo->qi_quotaofflock)
 
-#define XFS_QI_MPL_LIST(mp)	((mp)->m_quotainfo->qi_dqlist)
-#define XFS_QI_MPLNEXT(mp)	((mp)->m_quotainfo->qi_dqlist.qh_next)
-#define XFS_QI_MPLNDQUOTS(mp)	((mp)->m_quotainfo->qi_dqlist.qh_nelems)
-
-#define xfs_qm_mplist_lock(mp) \
-	mutex_lock(&(XFS_QI_MPL_LIST(mp).qh_lock))
-#define xfs_qm_mplist_nowait(mp) \
-	mutex_trylock(&(XFS_QI_MPL_LIST(mp).qh_lock))
-#define xfs_qm_mplist_unlock(mp) \
-	mutex_unlock(&(XFS_QI_MPL_LIST(mp).qh_lock))
-#define XFS_QM_IS_MPLIST_LOCKED(mp) \
-	mutex_is_locked(&(XFS_QI_MPL_LIST(mp).qh_lock))
-
 #define xfs_qm_freelist_lock(qm) \
 	mutex_lock(&((qm)->qm_dqfreelist.qh_lock))
 #define xfs_qm_freelist_lock_nowait(qm) \
@@ -88,8 +74,6 @@
 
 #define HL_PREVP	dq_hashlist.ql_prevp
 #define HL_NEXT		dq_hashlist.ql_next
-#define MPL_PREVP	dq_mplist.ql_prevp
-#define MPL_NEXT	dq_mplist.ql_next
 
 
 #define _LIST_REMOVE(h, dqp, PVP, NXT)				\
@@ -116,9 +100,6 @@
 		 (h)->qh_nelems++;				\
 	 }
 
-#define FOREACH_DQUOT_IN_MP(dqp, mp) \
-	for ((dqp) = XFS_QI_MPLNEXT(mp); (dqp) != NULL; (dqp) = (dqp)->MPL_NEXT)
-
 #define FOREACH_DQUOT_IN_FREELIST(dqp, qlist)	\
 for ((dqp) = (qlist)->qh_next; (dqp) != (xfs_dquot_t *)(qlist); \
      (dqp) = (dqp)->dq_flnext)
@@ -129,16 +110,10 @@ for ((dqp) = (qlist)->qh_next; (dqp) != (xfs_dquot_t *)(qlist); \
 #define XQM_FREELIST_INSERT(h, dqp)	\
 	 xfs_qm_freelist_append(h, dqp)
 
-#define XQM_MPLIST_INSERT(h, dqp)	\
-	 _LIST_INSERT(h, dqp, MPL_PREVP, MPL_NEXT)
-
 #define XQM_HASHLIST_REMOVE(h, dqp)	\
 	 _LIST_REMOVE(h, dqp, HL_PREVP, HL_NEXT)
 #define XQM_FREELIST_REMOVE(dqp)	\
 	 xfs_qm_freelist_unlink(dqp)
-#define XQM_MPLIST_REMOVE(h, dqp)	\
-	{ _LIST_REMOVE(h, dqp, MPL_PREVP, MPL_NEXT); \
-	  XFS_QI_MPLRECLAIMS((dqp)->q_mount)++; }
 
 #define XFS_DQ_IS_LOGITEM_INITD(dqp)	((dqp)->q_logitem.qli_dquot == (dqp))