[v4,2/5] PCI/sysfs: Use return value from dsm_label_utf16s_to_utf8s() directly

Commit Message

Krzysztof Wilczyński May 25, 2021, 12:23 p.m. UTC

Modify the function dsm_label_utf16s_to_utf8s() to directly return the
number of bytes written into the buffer so that the strlen() used later
to calculate the length of the buffer can be removed as it would no
longer be needed.

No functional change intended.

Signed-off-by: Krzysztof Wilczyński <[e-mail]>
Reviewed-by: Logan Gunthorpe <[e-mail]>
---
Changes in v2:
  None.
Changes in v3:
  None.
Changes in v4:
  Separated this patch from other trivial sysfs_emit()/sysfs_emit_at()
  patches into a separate patch as per Bjorn Helgaas' request.
  Added Logan Gunthorpe's "Reviewed-by".

 drivers/pci/pci-label.c | 18 ++++++++++--------
 1 file changed, 10 insertions(+), 8 deletions(-)

Patch

diff --git a/drivers/pci/pci-label.c b/drivers/pci/pci-label.c
index 311dd48e2881..000e169c7197 100644
--- a/drivers/pci/pci-label.c
+++ b/drivers/pci/pci-label.c
@@ -139,14 +139,17 @@  enum acpi_attr_enum {
 	ACPI_ATTR_INDEX_SHOW,
 };
 
-static void dsm_label_utf16s_to_utf8s(union acpi_object *obj, char *buf)
+static int dsm_label_utf16s_to_utf8s(union acpi_object *obj, char *buf)
 {
 	int len;
+
 	len = utf16s_to_utf8s((const wchar_t *)obj->buffer.pointer,
 			      obj->buffer.length,
 			      UTF16_LITTLE_ENDIAN,
 			      buf, PAGE_SIZE);
 	buf[len] = '\n';
+
+	return len;
 }
 
 static int dsm_get_label(struct device *dev, char *buf,
@@ -154,7 +157,7 @@  static int dsm_get_label(struct device *dev, char *buf,
 {
 	acpi_handle handle = ACPI_HANDLE(dev);
 	union acpi_object *obj, *tmp;
-	int len = -1;
+	int len = 0;
 
 	if (!handle)
 		return -1;
@@ -175,20 +178,19 @@  static int dsm_get_label(struct device *dev, char *buf,
 		 * this entry must return a null string.
 		 */
 		if (attr == ACPI_ATTR_INDEX_SHOW) {
-			sysfs_emit(buf, "%llu\n", tmp->integer.value);
+			len = sysfs_emit(buf, "%llu\n", tmp->integer.value);
 		} else if (attr == ACPI_ATTR_LABEL_SHOW) {
 			if (tmp[1].type == ACPI_TYPE_STRING)
-				sysfs_emit(buf, "%s\n",
-					   tmp[1].string.pointer);
+				len = sysfs_emit(buf, "%s\n",
+						 tmp[1].string.pointer);
 			else if (tmp[1].type == ACPI_TYPE_BUFFER)
-				dsm_label_utf16s_to_utf8s(tmp + 1, buf);
+				len = dsm_label_utf16s_to_utf8s(tmp + 1, buf);
 		}
-		len = strlen(buf) > 0 ? strlen(buf) : -1;
 	}
 
 	ACPI_FREE(obj);
 
-	return len;
+	return len > 0 ? len : -1;
 }
 
 static ssize_t label_show(struct device *dev, struct device_attribute *attr,