drm/i915: Lock ww in ucode objects correctly

In the ucode functions, the calls are done before userspace runs,
when debugging using debugfs, or when creating semi-permanent mappings;
we can safely use the unlocked versions that does the ww dance for us.

Because there is no pin_pages_unlocked yet, add it as convenience function.

This removes possible lockdep splats about missing resv lock for ucode.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210323155059.628690-37-maarten.lankhorst@linux.intel.com

drivers/gpu/drm/i915/gem/i915_gem_object.h

@@ -366,6 +366,8 @@ i915_gem_object_pin_pages(struct drm_i915_gem_object *obj)
 	return __i915_gem_object_get_pages(obj);
 }
 
+int i915_gem_object_pin_pages_unlocked(struct drm_i915_gem_object *obj);
+
 static inline bool
 i915_gem_object_has_pages(struct drm_i915_gem_object *obj)
 {

drivers/gpu/drm/i915/gem/i915_gem_pages.c

@@ -139,6 +139,26 @@ int __i915_gem_object_get_pages(struct drm_i915_gem_object *obj)
 	return err;
 }
 
+int i915_gem_object_pin_pages_unlocked(struct drm_i915_gem_object *obj)
+{
+	struct i915_gem_ww_ctx ww;
+	int err;
+
+	i915_gem_ww_ctx_init(&ww, true);
+retry:
+	err = i915_gem_object_lock(obj, &ww);
+	if (!err)
+		err = i915_gem_object_pin_pages(obj);
+
+	if (err == -EDEADLK) {
+		err = i915_gem_ww_ctx_backoff(&ww);
+		if (!err)
+			goto retry;
+	}
+	i915_gem_ww_ctx_fini(&ww);
+	return err;
+}
+
 /* Immediately discard the backing storage */
 void i915_gem_object_truncate(struct drm_i915_gem_object *obj)
 {

drivers/gpu/drm/i915/gt/uc/intel_guc.c

@@ -682,7 +682,7 @@ int intel_guc_allocate_and_map_vma(struct intel_guc *guc, u32 size,
 	if (IS_ERR(vma))
 		return PTR_ERR(vma);
 
-	vaddr = i915_gem_object_pin_map(vma->obj, I915_MAP_WB);
+	vaddr = i915_gem_object_pin_map_unlocked(vma->obj, I915_MAP_WB);
 	if (IS_ERR(vaddr)) {
 		i915_vma_unpin_and_release(&vma, 0);
 		return PTR_ERR(vaddr);

drivers/gpu/drm/i915/gt/uc/intel_guc_log.c

@@ -335,7 +335,7 @@ static int guc_log_map(struct intel_guc_log *log)
 	 * buffer pages, so that we can directly get the data
 	 * (up-to-date) from memory.
 	 */
-	vaddr = i915_gem_object_pin_map(log->vma->obj, I915_MAP_WC);
+	vaddr = i915_gem_object_pin_map_unlocked(log->vma->obj, I915_MAP_WC);
 	if (IS_ERR(vaddr))
 		return PTR_ERR(vaddr);
 
@@ -744,7 +744,7 @@ int intel_guc_log_dump(struct intel_guc_log *log, struct drm_printer *p,
 	if (!obj)
 		return 0;
 
-	map = i915_gem_object_pin_map(obj, I915_MAP_WC);
+	map = i915_gem_object_pin_map_unlocked(obj, I915_MAP_WC);
 	if (IS_ERR(map)) {
 		DRM_DEBUG("Failed to pin object\n");
 		drm_puts(p, "(log data unaccessible)\n");

drivers/gpu/drm/i915/gt/uc/intel_huc.c

@@ -82,7 +82,7 @@ static int intel_huc_rsa_data_create(struct intel_huc *huc)
 	if (IS_ERR(vma))
 		return PTR_ERR(vma);
 
-	vaddr = i915_gem_object_pin_map(vma->obj, I915_MAP_WB);
+	vaddr = i915_gem_object_pin_map_unlocked(vma->obj, I915_MAP_WB);
 	if (IS_ERR(vaddr)) {
 		i915_vma_unpin_and_release(&vma, 0);
 		return PTR_ERR(vaddr);

drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c

@@ -539,7 +539,7 @@ int intel_uc_fw_init(struct intel_uc_fw *uc_fw)
 	if (!intel_uc_fw_is_available(uc_fw))
 		return -ENOEXEC;
 
-	err = i915_gem_object_pin_pages(uc_fw->obj);
+	err = i915_gem_object_pin_pages_unlocked(uc_fw->obj);
 	if (err) {
 		DRM_DEBUG_DRIVER("%s fw pin-pages err=%d\n",
 				 intel_uc_fw_type_repr(uc_fw->type), err);