[PATCH 10/10] dma-buf/resv: add other operations

[Christian König]

Additional to readers and writers add another class of operations
which never participate in implicit synchronization.

Signed-off-by: Christian König <christian.koenig at amd.com>
---
 drivers/dma-buf/dma-resv.c | 27 ++++++++++++++++++++++++---
 include/linux/dma-resv.h   |  2 ++
 2 files changed, 26 insertions(+), 3 deletions(-)

diff --git a/drivers/dma-buf/dma-resv.c b/drivers/dma-buf/dma-resv.c
index 8ef7dbc7fd8e..c6dd6c36dba2 100644
--- a/drivers/dma-buf/dma-resv.c
+++ b/drivers/dma-buf/dma-resv.c
@@ -280,6 +280,7 @@ void dma_resv_init(struct dma_resv *obj)
 
 	dma_resv_fences_init(&obj->writers);
 	dma_resv_fences_init(&obj->readers);
+	dma_resv_fences_init(&obj->others);
 }
 EXPORT_SYMBOL(dma_resv_init);
 
@@ -295,6 +296,7 @@ void dma_resv_fini(struct dma_resv *obj)
 	 */
 	dma_resv_fences_fini(&obj->writers);
 	dma_resv_fences_fini(&obj->readers);
+	dma_resv_fences_fini(&obj->others);
 	ww_mutex_destroy(&obj->lock);
 }
 EXPORT_SYMBOL(dma_resv_fini);
@@ -334,6 +336,10 @@ void dma_resv_prune_fences(struct dma_resv *obj)
 	fence = dma_resv_fences_deref(obj, &obj->readers);
 	if (dma_fence_is_signaled(fence))
 		dma_resv_fences_set(obj, &obj->readers, NULL);
+
+	fence = dma_resv_fences_deref(obj, &obj->others);
+	if (dma_fence_is_signaled(fence))
+		dma_resv_fences_set(obj, &obj->others, NULL);
 }
 EXPORT_SYMBOL(dma_resv_prune_fences);
 
@@ -346,17 +352,19 @@ EXPORT_SYMBOL(dma_resv_prune_fences);
 */
 int dma_resv_copy_fences(struct dma_resv *dst, struct dma_resv *src)
 {
-	struct dma_fence *writers, *readers;
+	struct dma_fence *writers, *readers, *others;
 
 	dma_resv_assert_held(dst);
 
 	rcu_read_lock();
 	writers = dma_resv_fences_get_rcu(&src->writers);
 	readers = dma_resv_fences_get_rcu(&src->readers);
+	others = dma_resv_fences_get_rcu(&src->others);
 	rcu_read_unlock();
 
 	dma_resv_fences_set(dst, &dst->writers, writers);
 	dma_resv_fences_set(dst, &dst->readers, readers);
+	dma_resv_fences_set(dst, &dst->readers, others);
 
 	return 0;
 }
@@ -440,12 +448,13 @@ long dma_resv_wait_timeout_rcu(struct dma_resv *obj,
 			       bool wait_all, bool intr,
 			       unsigned long timeout)
 {
-	struct dma_fence *writers, *readers;
+	struct dma_fence *writers, *readers, *others;
 	long ret = timeout ? timeout : 1;
 
 	rcu_read_lock();
 	writers = dma_resv_fences_get_rcu(&obj->writers);
 	readers = dma_resv_fences_get_rcu(&obj->readers);
+	others = dma_resv_fences_get_rcu(&obj->others);
 	rcu_read_unlock();
 
 	if (wait_all && readers) {
@@ -454,12 +463,19 @@ long dma_resv_wait_timeout_rcu(struct dma_resv *obj,
 			goto out;
 	}
 
+	if (wait_all && others) {
+		ret = dma_fence_wait_timeout(others, intr, ret);
+		if (ret <= 0)
+			goto out;
+	}
+
 	if (writers)
 		ret = dma_fence_wait_timeout(writers, intr, ret);
 
 out:
 	dma_fence_put(writers);
 	dma_fence_put(readers);
+	dma_fence_put(others);
 	return ret;
 }
 EXPORT_SYMBOL_GPL(dma_resv_wait_timeout_rcu);
@@ -476,12 +492,13 @@ EXPORT_SYMBOL_GPL(dma_resv_wait_timeout_rcu);
  */
 bool dma_resv_test_signaled_rcu(struct dma_resv *obj, bool test_all)
 {
-	struct dma_fence *writers, *readers;
+	struct dma_fence *writers, *readers, *others;
 	bool ret = true;
 
 	rcu_read_lock();
 	writers = dma_resv_fences_get_rcu(&obj->writers);
 	readers = dma_resv_fences_get_rcu(&obj->readers);
+	others = dma_resv_fences_get_rcu(&obj->others);
 	rcu_read_unlock();
 
 	if (writers)
@@ -490,8 +507,12 @@ bool dma_resv_test_signaled_rcu(struct dma_resv *obj, bool test_all)
 	if (test_all && readers)
 		ret &= dma_fence_is_signaled(readers);
 
+	if (test_all && others)
+		ret &= dma_fence_is_signaled(others);
+
 	dma_fence_put(writers);
 	dma_fence_put(readers);
+	dma_fence_put(others);
 
 	return ret;
 }
diff --git a/include/linux/dma-resv.h b/include/linux/dma-resv.h
index 72c3c4f99711..bf8d21cc7720 100644
--- a/include/linux/dma-resv.h
+++ b/include/linux/dma-resv.h
@@ -76,12 +76,14 @@ void dma_resv_fences_commit(struct dma_resv *obj,
  * @seq: sequence count for managing RCU read-side synchronization
  * @writers: array of write operations for implicit sync
  * @readers: array of read operations for implicit sync
+ * @others: other operations not participating in implicit sync
  */
 struct dma_resv {
 	struct ww_mutex lock;
 
 	struct dma_resv_fences writers;
 	struct dma_resv_fences readers;
+	struct dma_resv_fences others;
 };
 
 #define dma_resv_held(obj) lockdep_is_held(&(obj)->lock.base)
-- 
2.17.1