iommu/vt-d: Factor out dmar_alloc_dev_scope() for later reuse
Factor out function dmar_alloc_dev_scope() from dmar_parse_dev_scope()
for later reuse.
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c
index 1581565..58dde75 100644
--- a/drivers/iommu/dmar.c
+++ b/drivers/iommu/dmar.c
@@ -117,13 +117,9 @@
return 0;
}
-int __init dmar_parse_dev_scope(void *start, void *end, int *cnt,
- struct pci_dev ***devices, u16 segment)
+void *dmar_alloc_dev_scope(void *start, void *end, int *cnt)
{
struct acpi_dmar_device_scope *scope;
- void * tmp = start;
- int index;
- int ret;
*cnt = 0;
while (start < end) {
@@ -138,15 +134,24 @@
start += scope->length;
}
if (*cnt == 0)
- return 0;
+ return NULL;
- *devices = kcalloc(*cnt, sizeof(struct pci_dev *), GFP_KERNEL);
- if (!*devices)
+ return kcalloc(*cnt, sizeof(struct pci_dev *), GFP_KERNEL);
+}
+
+int __init dmar_parse_dev_scope(void *start, void *end, int *cnt,
+ struct pci_dev ***devices, u16 segment)
+{
+ struct acpi_dmar_device_scope *scope;
+ int index, ret;
+
+ *devices = dmar_alloc_dev_scope(start, end, cnt);
+ if (*cnt == 0)
+ return 0;
+ else if (!*devices)
return -ENOMEM;
- start = tmp;
- index = 0;
- while (start < end) {
+ for (index = 0; start < end; start += scope->length) {
scope = start;
if (scope->entry_type == ACPI_DMAR_SCOPE_TYPE_ENDPOINT ||
scope->entry_type == ACPI_DMAR_SCOPE_TYPE_BRIDGE) {
@@ -158,7 +163,6 @@
}
index ++;
}
- start += scope->length;
}
return 0;