ACPI: use memory_read_from_buffer()
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/acpi/system.c b/drivers/acpi/system.c
index 769f248..5bd2dec 100644
--- a/drivers/acpi/system.c
+++ b/drivers/acpi/system.c
@@ -77,7 +77,6 @@
container_of(bin_attr, struct acpi_table_attr, attr);
struct acpi_table_header *table_header = NULL;
acpi_status status;
- ssize_t ret_count = count;
status =
acpi_get_table(table_attr->name, table_attr->instance,
@@ -85,18 +84,8 @@
if (ACPI_FAILURE(status))
return -ENODEV;
- if (offset >= table_header->length) {
- ret_count = 0;
- goto end;
- }
-
- if (offset + ret_count > table_header->length)
- ret_count = table_header->length - offset;
-
- memcpy(buf, ((char *)table_header) + offset, ret_count);
-
- end:
- return ret_count;
+ return memory_read_from_buffer(buf, count, &offset,
+ table_header, table_header->length);
}
static void acpi_table_attr_init(struct acpi_table_attr *table_attr,