drm/i915/uc: Move FW size sanity check back to fetch

While we need to know WOPCM size to do this sanity check, it has more to
do with FW than with WOPCM. Let's move the check to fetch phase, it's
not like WOPCM is going to grow in the meantime.

v2: rebased
v3: use __intel_uc_fw_get_upload_size (Daniele)
Signed-off-by: Michał Winiarski <michal.winiarski@intel.com>
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jackie Li <yaodong.li@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20190816105501.31020-2-michal.wajdeczko@intel.com

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

@@ -265,6 +265,7 @@ int intel_uc_fw_fetch(struct intel_uc_fw *uc_fw, struct drm_i915_private *i915)
 	size_t size;
 	int err;
 
+	GEM_BUG_ON(!i915->wopcm.size);
 	GEM_BUG_ON(!intel_uc_fw_supported(uc_fw));
 
 	err = i915_inject_load_error(i915, -ENXIO);
@@ -324,6 +325,16 @@ int intel_uc_fw_fetch(struct intel_uc_fw *uc_fw, struct drm_i915_private *i915)
 		goto fail;
 	}
 
+	/* Sanity check whether this fw is not larger than whole WOPCM memory */
+	size = __intel_uc_fw_get_upload_size(uc_fw);
+	if (unlikely(size >= i915->wopcm.size)) {
+		dev_warn(dev, "%s firmware %s: invalid size: %zu > %zu\n",
+			 intel_uc_fw_type_repr(uc_fw->type), uc_fw->path,
+			 size, (size_t)i915->wopcm.size);
+		err = -E2BIG;
+		goto fail;
+	}
+
 	/* Get version numbers from the CSS header */
 	switch (uc_fw->type) {
 	case INTEL_UC_FW_TYPE_GUC:

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

@@ -173,6 +173,11 @@ static inline void intel_uc_fw_sanitize(struct intel_uc_fw *uc_fw)
 		intel_uc_fw_change_status(uc_fw, INTEL_UC_FIRMWARE_AVAILABLE);
 }
 
+static inline u32 __intel_uc_fw_get_upload_size(struct intel_uc_fw *uc_fw)
+{
+	return sizeof(struct uc_css_header) + uc_fw->ucode_size;
+}
+
 /**
  * intel_uc_fw_get_upload_size() - Get size of firmware needed to be uploaded.
  * @uc_fw: uC firmware.
@@ -186,7 +191,7 @@ static inline u32 intel_uc_fw_get_upload_size(struct intel_uc_fw *uc_fw)
 	if (!intel_uc_fw_is_available(uc_fw))
 		return 0;
 
-	return sizeof(struct uc_css_header) + uc_fw->ucode_size;
+	return __intel_uc_fw_get_upload_size(uc_fw);
 }
 
 void intel_uc_fw_init_early(struct intel_uc_fw *uc_fw,

drivers/gpu/drm/i915/intel_wopcm.c

@@ -181,22 +181,12 @@ void intel_wopcm_init(struct intel_wopcm *wopcm)
 	GEM_BUG_ON(!wopcm->size);
 	GEM_BUG_ON(wopcm->guc.base);
 	GEM_BUG_ON(wopcm->guc.size);
+	GEM_BUG_ON(guc_fw_size >= wopcm->size);
+	GEM_BUG_ON(huc_fw_size >= wopcm->size);
 
 	if (i915_inject_probe_failure(i915))
 		return;
 
-	if (guc_fw_size >= wopcm->size) {
-		DRM_ERROR("GuC FW (%uKiB) is too big to fit in WOPCM.",
-			  guc_fw_size / 1024);
-		return;
-	}
-
-	if (huc_fw_size >= wopcm->size) {
-		DRM_ERROR("HuC FW (%uKiB) is too big to fit in WOPCM.",
-			  huc_fw_size / 1024);
-		return;
-	}
-
 	guc_wopcm_base = ALIGN(huc_fw_size + WOPCM_RESERVED_SIZE,
 			       GUC_WOPCM_OFFSET_ALIGNMENT);
 	if ((guc_wopcm_base + ctx_rsvd) >= wopcm->size) {