[PATCH libdrm 5/9] amdgpu: Add amdgpu_bo_handle_type_kms_user

[Michel Dänzer]

From: Michel Dänzer <michel.daenzer at amd.com>

amdgpu_bo_handle_type_kms returns the handle valid for the DRM file
descriptor (fd) used for CS submission etc. This is also valid for the
fd passed to amdgpu_device_initialize the first time for a specific
GPU, but in general not for fds passed to amdgpu_device_initialize
later for the same GPU.

Because some use-cases require a handle valid for the fd passed to
amdgpu_device_initialize, amdgpu_bo_handle_type_kms_user is added for
this purpose.

Signed-off-by: Michel Dänzer <michel.daenzer at amd.com>
---
 amdgpu/amdgpu.h          | 14 ++++++++-
 amdgpu/amdgpu_bo.c       | 65 +++++++++++++++++++++++++++-------------
 amdgpu/amdgpu_internal.h |  1 +
 3 files changed, 59 insertions(+), 21 deletions(-)

diff --git a/amdgpu/amdgpu.h b/amdgpu/amdgpu.h
index 66e45f73..f95c0a36 100644
--- a/amdgpu/amdgpu.h
+++ b/amdgpu/amdgpu.h
@@ -81,7 +81,14 @@ enum amdgpu_bo_handle_type {
 	/** GEM flink name (needs DRM authentication, used by DRI2) */
 	amdgpu_bo_handle_type_gem_flink_name = 0,
 
-	/** KMS handle which is used by all driver ioctls */
+	/** KMS handle which is used by all driver ioctls
+	 *
+	 * NOTE: The returned handle is valid for the DRM file description
+	 * used for command submission, which may be different from the one
+	 * referenced by the file descriptor passed to
+	 * amdgpu_device_initialize. Use amdgpu_bo_handle_type_kms_user to
+	 * get a handle valid for the latter.
+	 */
 	amdgpu_bo_handle_type_kms = 1,
 
 	/** DMA-buf fd handle */
@@ -91,6 +98,11 @@ enum amdgpu_bo_handle_type {
 	 * amdgpu_bo_handle_type_kms, use that instead of this
 	 */
 	amdgpu_bo_handle_type_kms_noimport = 3,
+
+	/** KMS handle valid for the DRM file description referenced by the
+	 * file descriptor passed to amdgpu_device_initialize.
+	 */
+	amdgpu_bo_handle_type_kms_user = 4,
 };
 
 /** Define known types of GPU VM VA ranges */
diff --git a/amdgpu/amdgpu_bo.c b/amdgpu/amdgpu_bo.c
index 7fec1f15..8d42db90 100644
--- a/amdgpu/amdgpu_bo.c
+++ b/amdgpu/amdgpu_bo.c
@@ -229,42 +229,58 @@ drm_public int amdgpu_bo_query_info(amdgpu_bo_handle user_bo,
 	return 0;
 }
 
+static int amdgpu_bo_get_user_handle(struct amdgpu_bo *user_bo,
+				     uint32_t *user_handle)
+{
+	struct amdgpu_device *user_dev = user_bo->dev;
+	struct amdgpu_core_device *dev = user_dev->core;
+	struct amdgpu_core_bo *bo = user_bo->core;
+	int dma_fd;
+	int r;
+
+	if (user_dev->user_fd == dev->fd) {
+		*user_handle = bo->handle;
+		return 0;
+	}
+
+	if (user_bo->user_handle)
+		goto out;
+
+	r = drmPrimeHandleToFD(dev->fd, bo->handle, DRM_CLOEXEC, &dma_fd);
+	if (r)
+		return r;
+
+	r = drmPrimeFDToHandle(user_dev->user_fd, dma_fd, &user_bo->user_handle);
+	close(dma_fd);
+	if (r)
+		return r;
+
+out:
+	*user_handle = user_bo->user_handle;
+	return 0;
+}
+
 static int amdgpu_bo_export_flink(amdgpu_bo_handle user_bo)
 {
 	struct amdgpu_core_device *dev = user_bo->dev->core;
 	struct amdgpu_core_bo *bo = user_bo->core;
-	int user_fd = user_bo->dev->user_fd;
 	struct drm_gem_flink flink;
-	int fd, dma_fd;
-	uint32_t handle;
 	int r;
 
-	fd = dev->fd;
-	handle = bo->handle;
 	if (bo->flink_name)
 		return 0;
 
-	if (user_fd != fd) {
-		r = drmPrimeHandleToFD(fd, bo->handle, DRM_CLOEXEC, &dma_fd);
-		if (!r) {
-			r = drmPrimeFDToHandle(user_fd, dma_fd, &handle);
-			close(dma_fd);
-		}
-		if (r)
-			return r;
-		fd = user_fd;
-	}
 	memset(&flink, 0, sizeof(flink));
-	flink.handle = handle;
 
-	r = drmIoctl(fd, DRM_IOCTL_GEM_FLINK, &flink);
+	r = amdgpu_bo_get_user_handle(user_bo, &flink.handle);
 	if (r)
 		return r;
 
-	bo->flink_name = flink.name;
+	r = drmIoctl(user_bo->dev->user_fd, DRM_IOCTL_GEM_FLINK, &flink);
+	if (r)
+		return r;
 
-	if (user_fd != dev->fd)
-		amdgpu_close_kms_handle(user_fd, handle);
+	bo->flink_name = flink.name;
 
 	pthread_mutex_lock(&dev->bo_table_mutex);
 	r = handle_table_insert(&dev->bo_flink_names, bo->flink_name, bo);
@@ -294,6 +310,9 @@ drm_public int amdgpu_bo_export(amdgpu_bo_handle user_bo,
 		*shared_handle = bo->handle;
 		return 0;
 
+	case amdgpu_bo_handle_type_kms_user:
+		return amdgpu_bo_get_user_handle(user_bo, shared_handle);
+
 	case amdgpu_bo_handle_type_dma_buf_fd:
 		return drmPrimeHandleToFD(user_bo->dev->core->fd, bo->handle,
 					  DRM_CLOEXEC | DRM_RDWR,
@@ -355,6 +374,7 @@ drm_public int amdgpu_bo_import(amdgpu_device_handle user_dev,
 
 	case amdgpu_bo_handle_type_kms:
 	case amdgpu_bo_handle_type_kms_noimport:
+	case amdgpu_bo_handle_type_kms_user:
 		/* Importing a KMS handle in not allowed. */
 		r = -EPERM;
 		goto unlock;
@@ -404,6 +424,7 @@ drm_public int amdgpu_bo_import(amdgpu_device_handle user_dev,
 
 	case amdgpu_bo_handle_type_kms:
 	case amdgpu_bo_handle_type_kms_noimport:
+	case amdgpu_bo_handle_type_kms_user:
 		assert(0); /* unreachable */
 	}
 
@@ -489,6 +510,10 @@ drm_public int amdgpu_bo_free(amdgpu_bo_handle buf_handle)
 
 	if (update_references(&user_bo->refcount, NULL)) {
 		amdgpu_core_bo_free(user_bo);
+		if (user_bo->user_handle) {
+			amdgpu_close_kms_handle(user_bo->dev->user_fd,
+						user_bo->user_handle);
+		}
 		free(user_bo);
 	}
 
diff --git a/amdgpu/amdgpu_internal.h b/amdgpu/amdgpu_internal.h
index 3a2ab74c..a08a4ae8 100644
--- a/amdgpu/amdgpu_internal.h
+++ b/amdgpu/amdgpu_internal.h
@@ -111,6 +111,7 @@ struct amdgpu_core_bo {
 
 struct amdgpu_bo {
 	atomic_t refcount;
+	uint32_t user_handle;
 	struct amdgpu_bo *next;
 	struct amdgpu_core_bo *core;
 	struct amdgpu_device *dev;
-- 
2.20.1