dma-buf: make fence sequence numbers 64 bit v2

For a lot of use cases we need 64bit sequence numbers. Currently drivers
overload the dma_fence structure to store the additional bits.

Stop doing that and make the sequence number in the dma_fence always
64bit.

For compatibility with hardware which can do only 32bit sequences the
comparisons in __dma_fence_is_later only takes the lower 32bits as significant
when the upper 32bits are all zero.

v2: change the logic in __dma_fence_is_later

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Chunming Zhou <david1.zhou@amd.com>
Link: https://patchwork.freedesktop.org/patch/266927/

drivers/dma-buf/dma-fence.c

@@ -649,7 +649,7 @@ EXPORT_SYMBOL(dma_fence_wait_any_timeout);
  */
 void
 dma_fence_init(struct dma_fence *fence, const struct dma_fence_ops *ops,
-	       spinlock_t *lock, u64 context, unsigned seqno)
+	       spinlock_t *lock, u64 context, u64 seqno)
 {
 	BUG_ON(!lock);
 	BUG_ON(!ops || !ops->get_driver_name || !ops->get_timeline_name);

drivers/dma-buf/sw_sync.c

@@ -172,7 +172,7 @@ static bool timeline_fence_enable_signaling(struct dma_fence *fence)
 static void timeline_fence_value_str(struct dma_fence *fence,
 				    char *str, int size)
 {
-	snprintf(str, size, "%d", fence->seqno);
+	snprintf(str, size, "%lld", fence->seqno);
 }
 
 static void timeline_fence_timeline_value_str(struct dma_fence *fence,

drivers/dma-buf/sync_file.c

@@ -144,7 +144,7 @@ char *sync_file_get_name(struct sync_file *sync_file, char *buf, int len)
 	} else {
 		struct dma_fence *fence = sync_file->fence;
 
-		snprintf(buf, len, "%s-%s%llu-%d",
+		snprintf(buf, len, "%s-%s%llu-%lld",
 			 fence->ops->get_driver_name(fence),
 			 fence->ops->get_timeline_name(fence),
 			 fence->context,
@@ -258,7 +258,7 @@ static struct sync_file *sync_file_merge(const char *name, struct sync_file *a,
 
 			i_b++;
 		} else {
-			if (pt_a->seqno - pt_b->seqno <= INT_MAX)
+			if (__dma_fence_is_later(pt_a->seqno, pt_b->seqno))
 				add_fence(fences, &i, pt_a);
 			else
 				add_fence(fences, &i, pt_b);