drm/i915/selftests: Replace mock_file hackery with drm's true fake

As drm now exports a method to create an anonymous struct file around a
drm_device for internal use, make use of it to avoid our horrible hacks.

Danial suggested that the mock_file_put() wrapper was suitable for
drm-core, along with the mock_drm_getfile() [and that the vestigal
mock_drm_file() in this patch should perhaps be the drm interface
itself]. However, the eventual goal is to remove the mock_drm_file() and
use the struct file and fput() directly, in this patch we take a simple
transition in that direction.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20191107180601.30815-3-chris@chris-wilson.co.uk

drivers/gpu/drm/i915/Kconfig.debug

@@ -29,6 +29,7 @@ config DRM_I915_DEBUG
 	select X86_MSR # used by igt/pm_rpm
 	select DRM_VGEM # used by igt/prime_vgem (dmabuf interop checks)
 	select DRM_DEBUG_MM if DRM=y
+	select DRM_EXPORT_FOR_TESTS if m
 	select DRM_DEBUG_SELFTEST
 	select DMABUF_SELFTESTS
 	select SW_SYNC # signaling validation framework (igt/syncobj*)
@@ -152,6 +153,7 @@ config DRM_I915_SELFTEST
 	bool "Enable selftests upon driver load"
 	depends on DRM_I915
 	default n
+	select DRM_EXPORT_FOR_TESTS if m
 	select FAULT_INJECTION
 	select PRIME_NUMBERS
 	help

drivers/gpu/drm/i915/gem/selftests/huge_pages.c

@@ -1944,6 +1944,6 @@ int i915_gem_huge_page_live_selftests(struct drm_i915_private *i915)
 	err = i915_subtests(tests, ctx);
 
 out_file:
-	mock_file_free(i915, file);
+	mock_file_put(file);
 	return err;
 }

drivers/gpu/drm/i915/gem/selftests/i915_gem_context.c

@@ -149,7 +149,7 @@ static int live_nop_switch(void *arg)
 	}
 
 out_file:
-	mock_file_free(i915, file);
+	mock_file_put(file);
 	return err;
 }
 
@@ -377,7 +377,7 @@ static int live_parallel_switch(void *arg)
 	}
 	kfree(data);
 out_file:
-	mock_file_free(i915, file);
+	mock_file_put(file);
 	return err;
 }
 
@@ -716,7 +716,7 @@ static int igt_ctx_exec(void *arg)
 		if (igt_live_test_end(&t))
 			err = -EIO;
 
-		mock_file_free(i915, file);
+		mock_file_put(file);
 		if (err)
 			return err;
 
@@ -854,7 +854,7 @@ static int igt_shared_ctx_exec(void *arg)
 	if (igt_live_test_end(&t))
 		err = -EIO;
 out_file:
-	mock_file_free(i915, file);
+	mock_file_put(file);
 	return err;
 }
 
@@ -1426,7 +1426,7 @@ static int igt_ctx_readonly(void *arg)
 	if (igt_live_test_end(&t))
 		err = -EIO;
 
-	mock_file_free(i915, file);
+	mock_file_put(file);
 	return err;
 }
 
@@ -1750,7 +1750,7 @@ static int igt_vm_isolation(void *arg)
 out_file:
 	if (igt_live_test_end(&t))
 		err = -EIO;
-	mock_file_free(i915, file);
+	mock_file_put(file);
 	return err;
 }
 

drivers/gpu/drm/i915/gem/selftests/i915_gem_object_blt.c

@@ -301,7 +301,7 @@ static int igt_fill_blt_thread(void *arg)
 
 	intel_context_put(ce);
 out_file:
-	mock_file_free(i915, file);
+	mock_file_put(file);
 	return err;
 }
 
@@ -432,7 +432,7 @@ static int igt_copy_blt_thread(void *arg)
 
 	intel_context_put(ce);
 out_file:
-	mock_file_free(i915, file);
+	mock_file_put(file);
 	return err;
 }
 

drivers/gpu/drm/i915/gt/selftest_context.c

@@ -313,7 +313,7 @@ static int live_active_context(void *arg)
 	}
 
 out_file:
-	mock_file_free(gt->i915, file);
+	mock_file_put(file);
 	return err;
 }
 
@@ -423,7 +423,7 @@ static int live_remote_context(void *arg)
 	}
 
 out_file:
-	mock_file_free(gt->i915, file);
+	mock_file_put(file);
 	return err;
 }
 

drivers/gpu/drm/i915/gt/selftest_hangcheck.c

@@ -439,7 +439,7 @@ static int igt_reset_nop(void *arg)
 
 	err = igt_flush_test(gt->i915);
 out:
-	mock_file_free(gt->i915, file);
+	mock_file_put(file);
 	if (intel_gt_is_wedged(gt))
 		err = -EIO;
 	return err;
@@ -535,7 +535,7 @@ static int igt_reset_nop_engine(void *arg)
 
 	err = igt_flush_test(gt->i915);
 out:
-	mock_file_free(gt->i915, file);
+	mock_file_put(file);
 	if (intel_gt_is_wedged(gt))
 		err = -EIO;
 	return err;
@@ -752,7 +752,7 @@ static int active_engine(void *data)
 	}
 
 err_file:
-	mock_file_free(engine->i915, file);
+	mock_file_put(file);
 	return err;
 }
 
@@ -1325,7 +1325,7 @@ static int igt_reset_evict_ppgtt(void *arg)
 	i915_vm_put(vm);
 
 out:
-	mock_file_free(gt->i915, file);
+	mock_file_put(file);
 	return err;
 }
 

drivers/gpu/drm/i915/gt/selftest_workarounds.c

@@ -739,7 +739,7 @@ static int live_dirty_whitelist(void *arg)
 	}
 
 out_file:
-	mock_file_free(gt->i915, file);
+	mock_file_put(file);
 	return err;
 }
 

drivers/gpu/drm/i915/selftests/i915_gem.c

@@ -163,7 +163,7 @@ static int igt_gem_suspend(void *arg)
 
 	err = switch_to_context(ctx);
 out:
-	mock_file_free(i915, file);
+	mock_file_put(file);
 	return err;
 }
 
@@ -198,7 +198,7 @@ static int igt_gem_hibernate(void *arg)
 
 	err = switch_to_context(ctx);
 out:
-	mock_file_free(i915, file);
+	mock_file_put(file);
 	return err;
 }
 

drivers/gpu/drm/i915/selftests/i915_gem_evict.c

@@ -515,7 +515,7 @@ static int igt_evict_contexts(void *arg)
 		pr_info("Submitted %lu contexts/requests on %s\n",
 			count, engine->name);
 
-		mock_file_free(i915, file);
+		mock_file_put(file);
 		if (err)
 			break;
 	}

drivers/gpu/drm/i915/selftests/i915_gem_gtt.c

@@ -1026,7 +1026,7 @@ static int exercise_ppgtt(struct drm_i915_private *dev_priv,
 	i915_vm_put(&ppgtt->vm);
 
 out_free:
-	mock_file_free(dev_priv, file);
+	mock_file_put(file);
 	return err;
 }
 
@@ -2022,7 +2022,7 @@ static int igt_cs_tlb(void *arg)
 out_vm:
 	i915_vm_put(vm);
 out_unlock:
-	mock_file_free(i915, file);
+	mock_file_put(file);
 	return err;
 }
 

drivers/gpu/drm/i915/selftests/i915_request.c

@@ -1430,7 +1430,7 @@ static int live_breadcrumbs_smoketest(void *arg)
 out_smoke:
 	kfree(smoke);
 out_file:
-	mock_file_free(i915, file);
+	mock_file_put(file);
 out_rpm:
 	intel_runtime_pm_put(&i915->runtime_pm, wakeref);
 

drivers/gpu/drm/i915/selftests/intel_memory_region.c

@@ -439,7 +439,7 @@ static int igt_lmem_write_gpu(void *arg)
 out_put:
 	i915_gem_object_put(obj);
 out_file:
-	mock_file_free(i915, file);
+	mock_file_put(file);
 	return err;
 }
 

drivers/gpu/drm/i915/selftests/mock_drm.c

@@ -22,52 +22,17 @@
  *
  */
 
+#include <drm/drm_file.h>
+
 #include "mock_drm.h"
 
 struct drm_file *mock_file(struct drm_i915_private *i915)
 {
-	struct file *filp;
-	struct inode *inode;
-	struct drm_file *file;
-	int err;
+	struct file *file;
 
-	inode = kzalloc(sizeof(*inode), GFP_KERNEL);
-	if (!inode) {
-		err = -ENOMEM;
-		goto err;
-	}
+	file = mock_drm_getfile(i915->drm.primary, O_RDWR);
+	if (IS_ERR(file))
+		return ERR_CAST(file);
 
-	inode->i_rdev = i915->drm.primary->index;
-
-	filp = kzalloc(sizeof(*filp), GFP_KERNEL);
-	if (!filp) {
-		err = -ENOMEM;
-		goto err_inode;
-	}
-
-	err = drm_open(inode, filp);
-	if (err)
-		goto err_filp;
-
-	file = filp->private_data;
-	memset(&file->filp, POISON_INUSE, sizeof(file->filp));
-	file->authenticated = true;
-
-	kfree(filp);
-	kfree(inode);
-	return file;
-
-err_filp:
-	kfree(filp);
-err_inode:
-	kfree(inode);
-err:
-	return ERR_PTR(err);
-}
-
-void mock_file_free(struct drm_i915_private *i915, struct drm_file *file)
-{
-	struct file filp = { .private_data = file };
-
-	drm_release(NULL, &filp);
+	return file->private_data;
 }

drivers/gpu/drm/i915/selftests/mock_drm.h

@@ -25,7 +25,13 @@
 #ifndef __MOCK_DRM_H
 #define __MOCK_DRM_H
 
+struct drm_file;
+struct drm_i915_private;
+
 struct drm_file *mock_file(struct drm_i915_private *i915);
-void mock_file_free(struct drm_i915_private *i915, struct drm_file *file);
+static inline void mock_file_put(struct drm_file *file)
+{
+	fput(file->filp);
+}
 
 #endif /* !__MOCK_DRM_H */