resource: Add resource_contains()
We have two identical copies of resource_contains() already, and more
places that could use it. This moves it to ioport.h where it can be
shared.
resource_contains(struct resource *r1, struct resource *r2) returns true
iff r1 and r2 are the same type (most callers already checked this
separately) and the r1 address range completely contains r2.
In addition, the new resource_contains() checks that both r1 and r2 have
addresses assigned to them. If a resource is IORESOURCE_UNSET, it doesn't
have a valid address and can't contain or be contained by another resource.
Some callers already check this or for res->start.
No functional change.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
diff --git a/include/linux/ioport.h b/include/linux/ioport.h
index 89b7c24..9fcaac8 100644
--- a/include/linux/ioport.h
+++ b/include/linux/ioport.h
@@ -169,6 +169,16 @@
{
return res->flags & IORESOURCE_TYPE_BITS;
}
+/* True iff r1 completely contains r2 */
+static inline bool resource_contains(struct resource *r1, struct resource *r2)
+{
+ if (resource_type(r1) != resource_type(r2))
+ return false;
+ if (r1->flags & IORESOURCE_UNSET || r2->flags & IORESOURCE_UNSET)
+ return false;
+ return r1->start <= r2->start && r1->end >= r2->end;
+}
+
/* Convenience shorthand with allocation */
#define request_region(start,n,name) __request_region(&ioport_resource, (start), (n), (name), 0)