[PATCH 2/4] amdgpu: add export/import semaphore apis

[Chunming Zhou]

They are used for sharing semaphore across process.

Change-Id: I262adf10913d365bb93368b492e69140af522c64
Signed-off-by: Chunming Zhou <David1.Zhou at amd.com>
---
 amdgpu/amdgpu.h          | 40 ++++++++++++++++++++++++++++++
 amdgpu/amdgpu_cs.c       | 63 ++++++++++++++++++++++++++++++++++++++++++++++--
 amdgpu/amdgpu_internal.h |  2 ++
 3 files changed, 103 insertions(+), 2 deletions(-)

diff --git a/amdgpu/amdgpu.h b/amdgpu/amdgpu.h
index 693d841..e716855 100644
--- a/amdgpu/amdgpu.h
+++ b/amdgpu/amdgpu.h
@@ -1379,6 +1379,19 @@ int amdgpu_svm_commit(amdgpu_va_handle va_range_handle,
 int amdgpu_svm_uncommit(amdgpu_va_handle va_range_handle);
 
 /**
+ *  create shared semaphore
+ *
+ * \param amdgpu_device_handle
+ * \param   sem	   - \c [out] semaphore handle
+ *
+ * \return   0 on success\n
+ *          <0 - Negative POSIX Error code
+ *
+*/
+int amdgpu_cs_create_semaphore_object(amdgpu_device_handle device_handle,
+				      amdgpu_semaphore_handle *sem);
+
+/**
  *  create semaphore
  *
  * \param   sem	   - \c [out] semaphore handle
@@ -1439,6 +1452,33 @@ int amdgpu_cs_wait_semaphore(amdgpu_context_handle ctx,
 int amdgpu_cs_destroy_semaphore(amdgpu_semaphore_handle sem);
 
 /**
+ *  export semaphore
+ *
+ * \param   sem	    - \c [in] semaphore handle
+ * \param   shared_handle    - \c [out] handle across process
+ *
+ * \return   0 on success\n
+ *          <0 - Negative POSIX Error code
+ *
+*/
+int amdgpu_cs_export_semaphore(amdgpu_semaphore_handle sem,
+			       uint32_t *shared_handle);
+/**
+ *  import semaphore
+ *
+ * \param   sem	    - \c [out] semaphore handle
+ * \param   dev	    - \c [in] device handle
+ * \param   shared_handle    - \c [in] handle across process
+ *
+ * \return   0 on success\n
+ *          <0 - Negative POSIX Error code
+ *
+*/
+int amdgpu_cs_import_semaphore(amdgpu_semaphore_handle *sem,
+			       amdgpu_device_handle dev,
+			       uint32_t shared_handle);
+
+/**
  *  Get the ASIC marketing name
  *
  * \param   dev         - \c [in] Device handle. See #amdgpu_device_initialize()
diff --git a/amdgpu/amdgpu_cs.c b/amdgpu/amdgpu_cs.c
index c76a675..a3ff34e 100644
--- a/amdgpu/amdgpu_cs.c
+++ b/amdgpu/amdgpu_cs.c
@@ -518,6 +518,34 @@ int amdgpu_cs_wait_fences(struct amdgpu_cs_fence *fences,
 	return r;
 }
 
+int amdgpu_cs_create_semaphore_object(amdgpu_device_handle device_handle,
+				      amdgpu_semaphore_handle *sem)
+{
+	struct amdgpu_bo_alloc_request req = {0};
+	amdgpu_bo_handle buf_handle;
+	int r;
+
+	if (NULL == sem)
+		return -EINVAL;
+
+	req.alloc_size = sizeof(struct amdgpu_semaphore);
+	req.preferred_heap = AMDGPU_GEM_DOMAIN_GTT;
+
+	r = amdgpu_bo_alloc(device_handle, &req, &buf_handle);
+	if (r)
+		return r;
+	r = amdgpu_bo_cpu_map(buf_handle, sem);
+	if (r) {
+		amdgpu_bo_free(buf_handle);
+		return r;
+	}
+	(*sem)->buf_handle = buf_handle;
+	atomic_set(&(*sem)->refcount, 1);
+	(*sem)->version = 2;
+
+	return 0;
+}
+
 int amdgpu_cs_create_semaphore(amdgpu_semaphore_handle *sem)
 {
 	struct amdgpu_semaphore *gpu_semaphore;
@@ -529,6 +557,7 @@ int amdgpu_cs_create_semaphore(amdgpu_semaphore_handle *sem)
 	if (NULL == gpu_semaphore)
 		return -ENOMEM;
 
+	gpu_semaphore->version = 1;
 	atomic_set(&gpu_semaphore->refcount, 1);
 	*sem = gpu_semaphore;
 
@@ -608,8 +637,15 @@ static int amdgpu_cs_unreference_sem(amdgpu_semaphore_handle sem)
 	if (NULL == sem)
 		return -EINVAL;
 
-	if (update_references(&sem->refcount, NULL))
-		free(sem);
+	if (update_references(&sem->refcount, NULL)) {
+		if (sem->version == 1)
+			free(sem);
+		else if (sem->version == 2) {
+			amdgpu_bo_handle buf_handle = sem->buf_handle;
+			amdgpu_bo_cpu_unmap(buf_handle);
+			amdgpu_bo_free(buf_handle);
+		}
+	}
 	return 0;
 }
 
@@ -618,4 +654,27 @@ int amdgpu_cs_destroy_semaphore(amdgpu_semaphore_handle sem)
 	return amdgpu_cs_unreference_sem(sem);
 }
 
+int amdgpu_cs_export_semaphore(amdgpu_semaphore_handle sem,
+			       uint32_t *shared_handle)
+{
+	return amdgpu_bo_export(sem->buf_handle,
+				amdgpu_bo_handle_type_dma_buf_fd,
+				shared_handle);
+
+}
+
+int amdgpu_cs_import_semaphore(amdgpu_semaphore_handle *sem,
+			       amdgpu_device_handle dev, uint32_t shared_handle)
+{
+	struct amdgpu_bo_import_result output;
+	int r;
+
+	r = amdgpu_bo_import(dev,
+			     amdgpu_bo_handle_type_dma_buf_fd,
+			     shared_handle,
+			     &output);
+	if (r)
+		return r;
 
+	return amdgpu_bo_cpu_map(output.buf_handle, sem);
+}
diff --git a/amdgpu/amdgpu_internal.h b/amdgpu/amdgpu_internal.h
index ccc85d7..7c422da 100644
--- a/amdgpu/amdgpu_internal.h
+++ b/amdgpu/amdgpu_internal.h
@@ -134,6 +134,8 @@ struct amdgpu_semaphore {
 	atomic_t refcount;
 	struct list_head list;
 	struct drm_amdgpu_fence signal_fence;
+	amdgpu_bo_handle buf_handle;
+	uint32_t version;
 };
 
 /**
-- 
1.9.1