dma-buf/drivers: make reserving a shared slot mandatory v4

Audit all the users of dma_resv_add_excl_fence() and make sure they
reserve a shared slot also when only trying to add an exclusive fence.

This is the next step towards handling the exclusive fence like a
shared one.

v2: fix missed case in amdgpu
v3: and two more radeon, rename function
v4: add one more case to TTM, fix i915 after rebase

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20220406075132.3263-2-christian.koenig@amd.com

2 files changed, 35 insertions, 39 deletions

diff --git a/drivers/dma-buf/dma-resv.c b/drivers/dma-buf/dma-resv.c
index 15ffac35439d..8c650b96357a 100644
--- a/drivers/dma-buf/dma-resv.c
+++ b/drivers/dma-buf/dma-resv.c
@@ -152,7 +152,7 @@ static inline struct dma_resv_list *dma_resv_shared_list(struct dma_resv *obj)
 }
 
 /**
- * dma_resv_reserve_shared - Reserve space to add shared fences to
+ * dma_resv_reserve_fences - Reserve space to add shared fences to
  * a dma_resv.
  * @obj: reservation object
  * @num_fences: number of fences we want to add
@@ -167,7 +167,7 @@ static inline struct dma_resv_list *dma_resv_shared_list(struct dma_resv *obj)
  * RETURNS
  * Zero for success, or -errno
  */
-int dma_resv_reserve_shared(struct dma_resv *obj, unsigned int num_fences)
+int dma_resv_reserve_fences(struct dma_resv *obj, unsigned int num_fences)
 {
 	struct dma_resv_list *old, *new;
 	unsigned int i, j, k, max;
@@ -230,7 +230,7 @@ int dma_resv_reserve_shared(struct dma_resv *obj, unsigned int num_fences)
 
 	return 0;
 }
-EXPORT_SYMBOL(dma_resv_reserve_shared);
+EXPORT_SYMBOL(dma_resv_reserve_fences);
 
 #ifdef CONFIG_DEBUG_MUTEXES
 /**
@@ -238,7 +238,7 @@ EXPORT_SYMBOL(dma_resv_reserve_shared);
  * @obj: the dma_resv object to reset
  *
  * Reset the number of pre-reserved shared slots to test that drivers do
- * correct slot allocation using dma_resv_reserve_shared(). See also
+ * correct slot allocation using dma_resv_reserve_fences(). See also
  * &dma_resv_list.shared_max.
  */
 void dma_resv_reset_shared_max(struct dma_resv *obj)
@@ -260,7 +260,7 @@ EXPORT_SYMBOL(dma_resv_reset_shared_max);
  * @fence: the shared fence to add
  *
  * Add a fence to a shared slot, @obj must be locked with dma_resv_lock(), and
- * dma_resv_reserve_shared() has been called.
+ * dma_resv_reserve_fences() has been called.
  *
  * See also &dma_resv.fence for a discussion of the semantics.
  */
diff --git a/drivers/dma-buf/st-dma-resv.c b/drivers/dma-buf/st-dma-resv.c
index cbe999c6e7a6..d2e61f6ae989 100644
--- a/drivers/dma-buf/st-dma-resv.c
+++ b/drivers/dma-buf/st-dma-resv.c
@@ -75,17 +75,16 @@ static int test_signaling(void *arg, bool shared)
 		goto err_free;
 	}
 
-	if (shared) {
-		r = dma_resv_reserve_shared(&resv, 1);
-		if (r) {
-			pr_err("Resv shared slot allocation failed\n");
-			goto err_unlock;
-		}
+	r = dma_resv_reserve_fences(&resv, 1);
+	if (r) {
+		pr_err("Resv shared slot allocation failed\n");
+		goto err_unlock;
+	}
 
+	if (shared)
 		dma_resv_add_shared_fence(&resv, f);
-	} else {
+	else
 		dma_resv_add_excl_fence(&resv, f);
-	}
 
 	if (dma_resv_test_signaled(&resv, shared)) {
 		pr_err("Resv unexpectedly signaled\n");
@@ -134,17 +133,16 @@ static int test_for_each(void *arg, bool shared)
 		goto err_free;
 	}
 
-	if (shared) {
-		r = dma_resv_reserve_shared(&resv, 1);
-		if (r) {
-			pr_err("Resv shared slot allocation failed\n");
-			goto err_unlock;
-		}
+	r = dma_resv_reserve_fences(&resv, 1);
+	if (r) {
+		pr_err("Resv shared slot allocation failed\n");
+		goto err_unlock;
+	}
 
+	if (shared)
 		dma_resv_add_shared_fence(&resv, f);
-	} else {
+	else
 		dma_resv_add_excl_fence(&resv, f);
-	}
 
 	r = -ENOENT;
 	dma_resv_for_each_fence(&cursor, &resv, shared, fence) {
@@ -206,18 +204,17 @@ static int test_for_each_unlocked(void *arg, bool shared)
 		goto err_free;
 	}
 
-	if (shared) {
-		r = dma_resv_reserve_shared(&resv, 1);
-		if (r) {
-			pr_err("Resv shared slot allocation failed\n");
-			dma_resv_unlock(&resv);
-			goto err_free;
-		}
+	r = dma_resv_reserve_fences(&resv, 1);
+	if (r) {
+		pr_err("Resv shared slot allocation failed\n");
+		dma_resv_unlock(&resv);
+		goto err_free;
+	}
 
+	if (shared)
 		dma_resv_add_shared_fence(&resv, f);
-	} else {
+	else
 		dma_resv_add_excl_fence(&resv, f);
-	}
 	dma_resv_unlock(&resv);
 
 	r = -ENOENT;
@@ -290,18 +287,17 @@ static int test_get_fences(void *arg, bool shared)
 		goto err_resv;
 	}
 
-	if (shared) {
-		r = dma_resv_reserve_shared(&resv, 1);
-		if (r) {
-			pr_err("Resv shared slot allocation failed\n");
-			dma_resv_unlock(&resv);
-			goto err_resv;
-		}
+	r = dma_resv_reserve_fences(&resv, 1);
+	if (r) {
+		pr_err("Resv shared slot allocation failed\n");
+		dma_resv_unlock(&resv);
+		goto err_resv;
+	}
 
+	if (shared)
 		dma_resv_add_shared_fence(&resv, f);
-	} else {
+	else
 		dma_resv_add_excl_fence(&resv, f);
-	}
 	dma_resv_unlock(&resv);
 
 	r = dma_resv_get_fences(&resv, shared, &i, &fences);