[PATCH 03/11] drm/msm: Add hint to DRM_IOCTL_MSM_GEM_INFO to return an object IOVA

[Jordan Crouse <jcrouse@codeaurora.org>]

Modify the 'pad' member of struct drm_msm_gem_info to 'hint'. If the
user sets 'hint' to non-zero it means that they want a IOVA for the
GEM object instead of a mmap() offset. Return the iova in the 'offset'
member.

Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
---
 drivers/gpu/drm/msm/msm_drv.c | 29 +++++++++++++++++++++++++----
 include/uapi/drm/msm_drm.h    |  4 ++--
 2 files changed, 27 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c
index e29bb66..1e4e022 100644
--- a/drivers/gpu/drm/msm/msm_drv.c
+++ b/drivers/gpu/drm/msm/msm_drv.c
@@ -677,6 +677,17 @@ static int msm_ioctl_gem_cpu_fini(struct drm_device *dev, void *data,
 	return ret;
 }
 
+static int msm_ioctl_gem_info_iova(struct drm_device *dev,
+		struct drm_gem_object *obj, uint64_t *iova)
+{
+	struct msm_drm_private *priv = dev->dev_private;
+
+	if (!priv->gpu)
+		return -EINVAL;
+
+	return msm_gem_get_iova(obj, priv->gpu->aspace, iova);
+}
+
 static int msm_ioctl_gem_info(struct drm_device *dev, void *data,
 		struct drm_file *file)
 {
@@ -684,14 +695,24 @@ static int msm_ioctl_gem_info(struct drm_device *dev, void *data,
 	struct drm_gem_object *obj;
 	int ret = 0;
 
-	if (args->pad)
-		return -EINVAL;
-
 	obj = drm_gem_object_lookup(file, args->handle);
 	if (!obj)
 		return -ENOENT;
 
-	args->offset = msm_gem_mmap_offset(obj);
+	/*
+	 * If the hint variable is set, it means that the user wants a IOVA for
+	 * this buffer.  Return the address from the GPU because that is
+	 * probably what it is looking for
+	 */
+	if (args->hint) {
+		uint64_t iova;
+
+		ret = msm_ioctl_gem_info_iova(dev, obj, &iova);
+		if (!ret)
+			args->offset = iova;
+	} else {
+		args->offset = msm_gem_mmap_offset(obj);
+	}
 
 	drm_gem_object_unreference_unlocked(obj);
 
diff --git a/include/uapi/drm/msm_drm.h b/include/uapi/drm/msm_drm.h
index 4d5d6a2..045ad20 100644
--- a/include/uapi/drm/msm_drm.h
+++ b/include/uapi/drm/msm_drm.h
@@ -105,8 +105,8 @@ struct drm_msm_gem_new {
 
 struct drm_msm_gem_info {
 	__u32 handle;         /* in */
-	__u32 pad;
-	__u64 offset;         /* out, offset to pass to mmap() */
+	__u32 hint;	      /* in */
+	__u64 offset;         /* out, mmap() offset if hint is 0, iova if 1 */
 };
 
 #define MSM_PREP_READ        0x01
-- 
1.9.1