xfs: convert the dquot free list to use list heads

Convert the dquot free list on the filesystem 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>

1 files changed, 31 insertions, 44 deletions

diff --git a/fs/xfs/quota/xfs_dquot.c b/fs/xfs/quota/xfs_dquot.c
index ad64ab6..02dac0a 100644
--- a/fs/xfs/quota/xfs_dquot.c
+++ b/fs/xfs/quota/xfs_dquot.c
@@ -101,7 +101,7 @@ xfs_qm_dqinit(
 	 * No need to re-initialize these if this is a reclaimed dquot.
 	 */
 	if (brandnewdquot) {
-		dqp->dq_flnext = dqp->dq_flprev = dqp;
+		INIT_LIST_HEAD(&dqp->q_freelist);
 		mutex_init(&dqp->q_qlock);
 		init_waitqueue_head(&dqp->q_pinwait);
 
@@ -119,20 +119,20 @@ xfs_qm_dqinit(
 		 * Only the q_core portion was zeroed in dqreclaim_one().
 		 * So, we need to reset others.
 		 */
-		 dqp->q_nrefs = 0;
-		 dqp->q_blkno = 0;
-		 INIT_LIST_HEAD(&dqp->q_mplist);
-		 INIT_LIST_HEAD(&dqp->q_hashlist);
-		 dqp->q_bufoffset = 0;
-		 dqp->q_fileoffset = 0;
-		 dqp->q_transp = NULL;
-		 dqp->q_gdquot = NULL;
-		 dqp->q_res_bcount = 0;
-		 dqp->q_res_icount = 0;
-		 dqp->q_res_rtbcount = 0;
-		 atomic_set(&dqp->q_pincount, 0);
-		 dqp->q_hash = NULL;
-		 ASSERT(dqp->dq_flnext == dqp->dq_flprev);
+		dqp->q_nrefs = 0;
+		dqp->q_blkno = 0;
+		INIT_LIST_HEAD(&dqp->q_mplist);
+		INIT_LIST_HEAD(&dqp->q_hashlist);
+		dqp->q_bufoffset = 0;
+		dqp->q_fileoffset = 0;
+		dqp->q_transp = NULL;
+		dqp->q_gdquot = NULL;
+		dqp->q_res_bcount = 0;
+		dqp->q_res_icount = 0;
+		dqp->q_res_rtbcount = 0;
+		atomic_set(&dqp->q_pincount, 0);
+		dqp->q_hash = NULL;
+		ASSERT(list_empty(&dqp->q_freelist));
 
 		trace_xfs_dqreuse(dqp);
 	}
@@ -158,7 +158,7 @@ void
 xfs_qm_dqdestroy(
 	xfs_dquot_t	*dqp)
 {
-	ASSERT(! XFS_DQ_IS_ON_FREELIST(dqp));
+	ASSERT(list_empty(&dqp->q_freelist));
 
 	mutex_destroy(&dqp->q_qlock);
 	sv_destroy(&dqp->q_pinwait);
@@ -775,8 +775,8 @@ xfs_qm_dqlookup(
 
 			xfs_dqlock(dqp);
 			if (dqp->q_nrefs == 0) {
-				ASSERT (XFS_DQ_IS_ON_FREELIST(dqp));
-				if (! xfs_qm_freelist_lock_nowait(xfs_Gqm)) {
+				ASSERT(!list_empty(&dqp->q_freelist));
+				if (!mutex_trylock(&xfs_Gqm->qm_dqfrlist_lock)) {
 					trace_xfs_dqlookup_want(dqp);
 
 					/*
@@ -786,7 +786,7 @@ xfs_qm_dqlookup(
 					 */
 					dqp->dq_flags |= XFS_DQ_WANT;
 					xfs_dqunlock(dqp);
-					xfs_qm_freelist_lock(xfs_Gqm);
+					mutex_lock(&xfs_Gqm->qm_dqfrlist_lock);
 					xfs_dqlock(dqp);
 					dqp->dq_flags &= ~(XFS_DQ_WANT);
 				}
@@ -801,27 +801,20 @@ xfs_qm_dqlookup(
 
 			if (flist_locked) {
 				if (dqp->q_nrefs != 0) {
-					xfs_qm_freelist_unlock(xfs_Gqm);
+					mutex_unlock(&xfs_Gqm->qm_dqfrlist_lock);
 					flist_locked = B_FALSE;
 				} else {
-					/*
-					 * take it off the freelist
-					 */
+					/* take it off the freelist */
 					trace_xfs_dqlookup_freelist(dqp);
-					XQM_FREELIST_REMOVE(dqp);
-					/* xfs_qm_freelist_print(&(xfs_Gqm->
-							qm_dqfreelist),
-							"after removal"); */
+					list_del_init(&dqp->q_freelist);
+					xfs_Gqm->qm_dqfrlist_cnt--;
 				}
 			}
 
-			/*
-			 * grab a reference
-			 */
 			XFS_DQHOLD(dqp);
 
 			if (flist_locked)
-				xfs_qm_freelist_unlock(xfs_Gqm);
+				mutex_unlock(&xfs_Gqm->qm_dqfrlist_lock);
 			/*
 			 * move the dquot to the front of the hashchain
 			 */
@@ -1075,10 +1068,10 @@ xfs_qm_dqput(
 	 * drop the dqlock and acquire the freelist and dqlock
 	 * in the right order; but try to get it out-of-order first
 	 */
-	if (! xfs_qm_freelist_lock_nowait(xfs_Gqm)) {
+	if (!mutex_trylock(&xfs_Gqm->qm_dqfrlist_lock)) {
 		trace_xfs_dqput_wait(dqp);
 		xfs_dqunlock(dqp);
-		xfs_qm_freelist_lock(xfs_Gqm);
+		mutex_lock(&xfs_Gqm->qm_dqfrlist_lock);
 		xfs_dqlock(dqp);
 	}
 
@@ -1089,10 +1082,8 @@ xfs_qm_dqput(
 		if (--dqp->q_nrefs == 0) {
 			trace_xfs_dqput_free(dqp);
 
-			/*
-			 * insert at end of the freelist.
-			 */
-			XQM_FREELIST_INSERT(&(xfs_Gqm->qm_dqfreelist), dqp);
+			list_add_tail(&dqp->q_freelist, &xfs_Gqm->qm_dqfrlist);
+			xfs_Gqm->qm_dqfrlist_cnt++;
 
 			/*
 			 * If we just added a udquot to the freelist, then
@@ -1107,10 +1098,6 @@ xfs_qm_dqput(
 				xfs_dqlock(gdqp);
 				dqp->q_gdquot = NULL;
 			}
-
-			/* xfs_qm_freelist_print(&(xfs_Gqm->qm_dqfreelist),
-			   "@@@@@++ Free list (after append) @@@@@+");
-			   */
 		}
 		xfs_dqunlock(dqp);
 
@@ -1122,7 +1109,7 @@ xfs_qm_dqput(
 			break;
 		dqp = gdqp;
 	}
-	xfs_qm_freelist_unlock(xfs_Gqm);
+	mutex_unlock(&xfs_Gqm->qm_dqfrlist_lock);
 }
 
 /*
@@ -1396,7 +1383,7 @@ xfs_qm_dqpurge(
 		return (1);
 	}
 
-	ASSERT(XFS_DQ_IS_ON_FREELIST(dqp));
+	ASSERT(!list_empty(&dqp->q_freelist));
 
 	/*
 	 * If we're turning off quotas, we have to make sure that, for
@@ -1450,7 +1437,7 @@ xfs_qm_dqpurge(
 	 * XXX Move this to the front of the freelist, if we can get the
 	 * freelist lock.
 	 */
-	ASSERT(XFS_DQ_IS_ON_FREELIST(dqp));
+	ASSERT(!list_empty(&dqp->q_freelist));
 
 	dqp->q_mount = NULL;
 	dqp->q_hash = NULL;