1/2 Make insert_resource work for alder IOAPIC resources
PATCH 1/1 1/2 Make insert_resource work for alder IOAPIC resources
This is a necessary precursor patch for getting the Intel Alder motherboard working (it has a PCI device corresponding to the IO-APIC which has to be forcibly inserted into the machine's reserved memory region).
Eric Biederman was going to come up with a more comprehensive fix, but in the meantime, this is the minimum necessary to get insert_resource to work when the covering region is larger than the resource being inserted.
James
===== kernel/resource.c 1.20 vs edited =====
kernel/resource.c +11 -7
@@ -306,11 +306,12 @@* * Returns 0 on success, -EBUSY if the resource can't be inserted. * -* This function is equivalent of request_resource when no -* conflict happens. If a conflict happens, and the conflicting -* resources entirely fit within the range of the new resource, -* then the new resource is inserted and the conflicting resources -* become childs of the new resource. +* This function is equivalent of request_resource when no conflict +* happens. If a conflict happens, and the conflicting resources +* entirely fit within the range of the new resource, then the new +* resource is inserted and the conflicting resources become childs of +* the new resource. Otherwise the new resource becomes the child of +* the conflicting resource */ int insert_resource (struct resource *parent,struct resource *new) {
@@ -318,6 +319,7 @@struct resource *first, *next;write_lock (&resource_lock); + begin: first =__request_resource (parent, new);if (!first) goto out;
@@ -331,8 +333,10 @@break ;/* existing resource overlaps end of new resource */ -if (next->end > new->end) - goto out; +if (next->end > new->end) { + parent = next; + goto begin; + } result =0 ;