gfs2: qd_check_sync cleanups

Rename qd_check_sync() to qd_grab_sync() and make it return a bool.
Turn the sync_gen pointer into a regular u64 and pass in U64_MAX instead
of a NULL pointer when sync generation checking isn't needed.

Introduce a new qd_ungrab_sync() helper for undoing the effects of
qd_grab_sync() if the subsequent bh_get() on the qd object fails.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

diff --git a/fs/gfs2/quota.c b/fs/gfs2/quota.c
index e0840b412d284c37e52acad831bdd9e76d4bca8a..bbd66adaec3d4993e27e740b64f0ca6f54433a5a 100644 (file)
--- a/fs/gfs2/quota.c
+++ b/fs/gfs2/quota.c
@@ -462,13 +462,13 @@ static void bh_put(struct gfs2_quota_data *qd)
        mutex_unlock(&sdp->sd_quota_mutex);
 }
 
-static int qd_check_sync(struct gfs2_sbd *sdp, struct gfs2_quota_data *qd,
-                        u64 *sync_gen)
+static bool qd_grab_sync(struct gfs2_sbd *sdp, struct gfs2_quota_data *qd,
+                        u64 sync_gen)
 {
        if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
            !test_bit(QDF_CHANGE, &qd->qd_flags) ||
-           (sync_gen && (qd->qd_sync_gen >= *sync_gen)))
-               return 0;
+           qd->qd_sync_gen >= sync_gen)
+               return false;
 
        /*
         * If qd_change is 0 it means a pending quota change was negated.
@@ -478,17 +478,24 @@ static int qd_check_sync(struct gfs2_sbd *sdp, struct gfs2_quota_data *qd,
        if (!qd->qd_change && test_and_clear_bit(QDF_CHANGE, &qd->qd_flags)) {
                slot_put(qd);
                qd_put(qd);
-               return 0;
+               return false;
        }
 
        if (!lockref_get_not_dead(&qd->qd_lockref))
-               return 0;
+               return false;
 
        list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
        set_bit(QDF_LOCKED, &qd->qd_flags);
        qd->qd_change_sync = qd->qd_change;
        slot_hold(qd);
-       return 1;
+       return true;
+}
+
+static void qd_ungrab_sync(struct gfs2_quota_data *qd)
+{
+       clear_bit(QDF_LOCKED, &qd->qd_flags);
+       slot_put(qd);
+       qd_put(qd);
 }
 
 static int qd_fish(struct gfs2_sbd *sdp, struct gfs2_quota_data **qdp)
@@ -504,7 +511,7 @@ static int qd_fish(struct gfs2_sbd *sdp, struct gfs2_quota_data **qdp)
        spin_lock(&qd_lock);
 
        list_for_each_entry(iter, &sdp->sd_quota_list, qd_list) {
-               if (qd_check_sync(sdp, iter, &sdp->sd_quota_sync_gen)) {
+               if (qd_grab_sync(sdp, iter, sdp->sd_quota_sync_gen)) {
                        qd = iter;
                        break;
                }
@@ -515,9 +522,7 @@ static int qd_fish(struct gfs2_sbd *sdp, struct gfs2_quota_data **qdp)
        if (qd) {
                error = bh_get(qd);
                if (error) {
-                       clear_bit(QDF_LOCKED, &qd->qd_flags);
-                       slot_put(qd);
-                       qd_put(qd);
+                       qd_ungrab_sync(qd);
                        return error;
                }
        }
@@ -1157,7 +1162,6 @@ void gfs2_quota_unlock(struct gfs2_inode *ip)
        struct gfs2_quota_data *qda[2 * GFS2_MAXQUOTAS];
        unsigned int count = 0;
        u32 x;
-       int found;
 
        if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
                return;
@@ -1165,6 +1169,7 @@ void gfs2_quota_unlock(struct gfs2_inode *ip)
        for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
                struct gfs2_quota_data *qd;
                bool sync;
+               int error;
 
                qd = ip->i_qadata->qa_qd[x];
                sync = need_sync(qd);
@@ -1174,17 +1179,16 @@ void gfs2_quota_unlock(struct gfs2_inode *ip)
                        continue;
 
                spin_lock(&qd_lock);
-               found = qd_check_sync(sdp, qd, NULL);
+               sync = qd_grab_sync(sdp, qd, U64_MAX);
                spin_unlock(&qd_lock);
 
-               if (!found)
+               if (!sync)
                        continue;
 
                gfs2_assert_warn(sdp, qd->qd_change_sync);
-               if (bh_get(qd)) {
-                       clear_bit(QDF_LOCKED, &qd->qd_flags);
-                       slot_put(qd);
-                       qd_put(qd);
+               error = bh_get(qd);
+               if (error) {
+                       qd_ungrab_sync(qd);
                        continue;
                }