[Intel-gfx] [PATCH 1/3] drm/i915: Added a new 'I915_CPU_MAP_NOT_NEEDED' flag to gem_create ioctl.

[sourab.gupta at intel.com]

From: Sourab Gupta <sourab.gupta at intel.com>

Adding the flag 'I915_CPU_MAP_NOT_NEEDED' to gem_create ioctl.
This is to indicate the driver that direct cpu access to this
buffer object is not needed and hence Driver can opt to use Stolen
area as a backing store for it. When this flag is set, try to
allocate the objects from Stolen area. Fallback to shmem in case
of allocation failure.

Signed-off-by: Sourab Gupta <sourab.gupta at intel.com>

Signed-off-by: Akash Goel <akash.goel at intel.com>
---
 drivers/gpu/drm/i915/i915_gem.c |   17 ++++++++++++-----
 include/uapi/drm/i915_drm.h     |    3 ++-
 2 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 177c207..22b531a 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -225,9 +225,11 @@ static int
 i915_gem_create(struct drm_file *file,
 		struct drm_device *dev,
 		uint64_t size,
-		uint32_t *handle_p)
+		uint32_t *handle_p,
+		uint32_t flags)
+
 {
-	struct drm_i915_gem_object *obj;
+	struct drm_i915_gem_object *obj=NULL;
 	int ret;
 	u32 handle;
 
@@ -236,7 +238,12 @@ i915_gem_create(struct drm_file *file,
 		return -EINVAL;
 
 	/* Allocate the new object */
-	obj = i915_gem_alloc_object(dev, size);
+	if (flags & I915_CPU_MAP_NOT_NEEDED)
+		obj = i915_gem_object_create_stolen(dev, size);
+
+	if (obj == NULL)
+		obj = i915_gem_alloc_object(dev, size);
+
 	if (obj == NULL)
 		return -ENOMEM;
 
@@ -259,7 +266,7 @@ i915_gem_dumb_create(struct drm_file *file,
 	args->pitch = ALIGN(args->width * DIV_ROUND_UP(args->bpp, 8), 64);
 	args->size = args->pitch * args->height;
 	return i915_gem_create(file, dev,
-			       args->size, &args->handle);
+			       args->size, &args->handle, args->flags);
 }
 
 /**
@@ -272,7 +279,7 @@ i915_gem_create_ioctl(struct drm_device *dev, void *data,
 	struct drm_i915_gem_create *args = data;
 
 	return i915_gem_create(file, dev,
-			       args->size, &args->handle);
+			       args->size, &args->handle, args->flags);
 }
 
 static inline int
diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
index 126bfaa..8625f54 100644
--- a/include/uapi/drm/i915_drm.h
+++ b/include/uapi/drm/i915_drm.h
@@ -431,7 +431,8 @@ struct drm_i915_gem_create {
 	 * Object handles are nonzero.
 	 */
 	__u32 handle;
-	__u32 pad;
+	__u32 flags;
+#define I915_CPU_MAP_NOT_NEEDED 0x1
 };
 
 struct drm_i915_gem_pread {
-- 
1.7.9.5