Revert "gfs2: Replace gl_revokes with a GLF flag"

Commit 73118ca8baf7 introduced a glock reference counting bug in
gfs2_trans_remove_revoke.  Given that, replacing gl_revokes with a GLF flag is
no longer useful, so revert that commit.

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

1 files changed, 9 insertions, 24 deletions

diff --git a/fs/gfs2/lops.c b/fs/gfs2/lops.c
index 33ab662c9aac..bb0e5b8e445e 100644
--- a/fs/gfs2/lops.c
+++ b/fs/gfs2/lops.c
@@ -860,34 +860,19 @@ static void revoke_lo_before_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
 static void revoke_lo_after_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
 {
 	struct list_head *head = &sdp->sd_log_revokes;
-	struct gfs2_bufdata *bd, *tmp;
-
-	/*
-	 * Glocks can be referenced repeatedly on the revoke list, but the list
-	 * only holds one reference.  All glocks on the list will have the
-	 * GLF_REVOKES flag set initially.
-	 */
-
-	list_for_each_entry_safe(bd, tmp, head, bd_list) {
-		struct gfs2_glock *gl = bd->bd_gl;
+	struct gfs2_bufdata *bd;
+	struct gfs2_glock *gl;
 
-		if (test_bit(GLF_REVOKES, &gl->gl_flags)) {
-			/* Keep each glock on the list exactly once. */
-			clear_bit(GLF_REVOKES, &gl->gl_flags);
-			continue;
+	while (!list_empty(head)) {
+		bd = list_entry(head->next, struct gfs2_bufdata, bd_list);
+		list_del_init(&bd->bd_list);
+		gl = bd->bd_gl;
+		if (atomic_dec_return(&gl->gl_revokes) == 0) {
+			clear_bit(GLF_LFLUSH, &gl->gl_flags);
+			gfs2_glock_queue_put(gl);
 		}
-		list_del(&bd->bd_list);
-		kmem_cache_free(gfs2_bufdata_cachep, bd);
-	}
-	list_for_each_entry_safe(bd, tmp, head, bd_list) {
-		struct gfs2_glock *gl = bd->bd_gl;
-
-		list_del(&bd->bd_list);
 		kmem_cache_free(gfs2_bufdata_cachep, bd);
-		clear_bit(GLF_LFLUSH, &gl->gl_flags);
-		gfs2_glock_queue_put(gl);
 	}
-	/* the list is empty now */
 }
 
 static void revoke_lo_before_scan(struct gfs2_jdesc *jd,