[PATCH v2 37/37] HAX drm/i915/lmem: default userspace allocations to LMEM

Matthew Auld
2019-06-27T20:57:25Z

Hack patch to default all userspace allocations to LMEM. Useful for
testing purposes.

Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Abdiel Janulgue <abdiel.janulgue@linux.intel.com>
---
drivers/gpu/drm/i915/i915_gem.c | 37 +++++++++++++++++++++++++++++++++
1 file changed, 37 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index ecdaca437797..a6f29acfb300 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -44,6 +44,7 @@
#include "gem/i915_gem_clflush.h"
#include "gem/i915_gem_context.h"
#include "gem/i915_gem_ioctls.h"
+#include "gem/i915_gem_object_blt.h"
#include "gem/i915_gem_pm.h"
#include "gt/intel_gt.h"
#include "gt/intel_gt_pm.h"
@@ -164,9 +165,45 @@ i915_gem_create(struct drm_file *file,

/* Allocate the new object */
obj = i915_gem_object_create_shmem(dev_priv, size);
+ if (HAS_LMEM(dev_priv))
+ obj = i915_gem_object_create_lmem(dev_priv, size, 0);
+ else
+ obj = i915_gem_object_create_shmem(dev_priv, size);
if (IS_ERR(obj))
return PTR_ERR(obj);

+ if (i915_gem_object_is_lmem(obj)) {
+ struct intel_context *ce =
+ dev_priv->engine[BCS0]->kernel_context;
+
+ /*
+ * XXX: We really want to move this to get_pages(), but we
+ * require grabbing the BKL for the blitting operation which is
+ * annoying. In the pipeline is support for async get_pages()
+ * which should fit nicely for this. Also note that the actual
+ * clear should be done async(we currently do an object_wait
+ * which is pure garbage), we just need to take care if
+ * userspace opts of implicit sync for the execbuf, to avoid any
+ * potential info leak.
+ */
+
+ mutex_lock(&dev_priv->drm.struct_mutex);
+ ret = i915_gem_object_fill_blt(obj, ce, 0);
+ mutex_unlock(&dev_priv->drm.struct_mutex);
+ if (ret) {
+ i915_gem_object_put(obj);
+ return ret;
+ }
+
+ i915_gem_object_lock(obj);
+ ret = i915_gem_object_set_to_cpu_domain(obj, false);
+ i915_gem_object_unlock(obj);
+ if (ret) {
+ i915_gem_object_put(obj);
+ return ret;
+ }
+ }
+
ret = drm_gem_handle_create(file, &obj->base, &handle);
/* drop reference from allocate - handle holds it now */
i915_gem_object_put(obj);
--
2.20.1