soc: qcom: mdt_loader: Split out split-file-loader

Spotted in a SM8450 device, the hash metadata segment is split out in a
separate .bNN file which means that the logic for loading split out
segmenents needs to be duplicated in qcom_mdt_read_metadata().

Split out the existing logic to a helper function that can be used in
both code paths.
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20220128025513.97188-3-bjorn.andersson@linaro.org

drivers/soc/qcom/mdt_loader.c

@@ -31,6 +31,44 @@ static bool mdt_phdr_valid(const struct elf32_phdr *phdr)
 	return true;
 }
 
+static ssize_t mdt_load_split_segment(void *ptr, const struct elf32_phdr *phdrs,
+				      unsigned int segment, const char *fw_name,
+				      struct device *dev)
+{
+	const struct elf32_phdr *phdr = &phdrs[segment];
+	const struct firmware *seg_fw;
+	char *seg_name;
+	ssize_t ret;
+
+	if (strlen(fw_name) < 4)
+		return -EINVAL;
+
+	seg_name = kstrdup(fw_name, GFP_KERNEL);
+	if (!seg_name)
+		return -ENOMEM;
+
+	sprintf(seg_name + strlen(fw_name) - 3, "b%02d", segment);
+	ret = request_firmware_into_buf(&seg_fw, seg_name, dev,
+					ptr, phdr->p_filesz);
+	if (ret) {
+		dev_err(dev, "error %zd loading %s\n", ret, seg_name);
+		kfree(seg_name);
+		return ret;
+	}
+
+	if (seg_fw->size != phdr->p_filesz) {
+		dev_err(dev,
+			"failed to load segment %d from truncated file %s\n",
+			segment, seg_name);
+		ret = -EINVAL;
+	}
+
+	release_firmware(seg_fw);
+	kfree(seg_name);
+
+	return ret;
+}
+
 /**
  * qcom_mdt_get_size() - acquire size of the memory region needed to load mdt
  * @fw:		firmware object for the mdt file
@@ -127,22 +165,19 @@ void *qcom_mdt_read_metadata(const struct firmware *fw, size_t *data_len)
 EXPORT_SYMBOL_GPL(qcom_mdt_read_metadata);
 
 static int __qcom_mdt_load(struct device *dev, const struct firmware *fw,
-			   const char *firmware, int pas_id, void *mem_region,
+			   const char *fw_name, int pas_id, void *mem_region,
 			   phys_addr_t mem_phys, size_t mem_size,
 			   phys_addr_t *reloc_base, bool pas_init)
 {
 	const struct elf32_phdr *phdrs;
 	const struct elf32_phdr *phdr;
 	const struct elf32_hdr *ehdr;
-	const struct firmware *seg_fw;
 	phys_addr_t mem_reloc;
 	phys_addr_t min_addr = PHYS_ADDR_MAX;
 	phys_addr_t max_addr = 0;
 	size_t metadata_len;
-	size_t fw_name_len;
 	ssize_t offset;
 	void *metadata;
-	char *fw_name;
 	bool relocate = false;
 	void *ptr;
 	int ret = 0;
@@ -154,14 +189,6 @@ static int __qcom_mdt_load(struct device *dev, const struct firmware *fw,
 	ehdr = (struct elf32_hdr *)fw->data;
 	phdrs = (struct elf32_phdr *)(ehdr + 1);
 
-	fw_name_len = strlen(firmware);
-	if (fw_name_len <= 4)
-		return -EINVAL;
-
-	fw_name = kstrdup(firmware, GFP_KERNEL);
-	if (!fw_name)
-		return -ENOMEM;
-
 	if (pas_init) {
 		metadata = qcom_mdt_read_metadata(fw, &metadata_len);
 		if (IS_ERR(metadata)) {
@@ -258,25 +285,9 @@ static int __qcom_mdt_load(struct device *dev, const struct firmware *fw,
 			memcpy(ptr, fw->data + phdr->p_offset, phdr->p_filesz);
 		} else if (phdr->p_filesz) {
 			/* Firmware not large enough, load split-out segments */
-			sprintf(fw_name + fw_name_len - 3, "b%02d", i);
-			ret = request_firmware_into_buf(&seg_fw, fw_name, dev,
-							ptr, phdr->p_filesz);
-			if (ret) {
-				dev_err(dev, "error %d loading %s\n",
-					ret, fw_name);
+			ret = mdt_load_split_segment(ptr, phdrs, i, fw_name, dev);
+			if (ret)
 				break;
-			}
-
-			if (seg_fw->size != phdr->p_filesz) {
-				dev_err(dev,
-					"failed to load segment %d from truncated file %s\n",
-					i, fw_name);
-				release_firmware(seg_fw);
-				ret = -EINVAL;
-				break;
-			}
-
-			release_firmware(seg_fw);
 		}
 
 		if (phdr->p_memsz > phdr->p_filesz)
@@ -287,7 +298,6 @@ static int __qcom_mdt_load(struct device *dev, const struct firmware *fw,
 		*reloc_base = mem_reloc;
 
 out:
-	kfree(fw_name);
 
 	return ret;
 }