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 ad64ab62d9c5..02dac0a5f1ec 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;