Re: [PATCH 2/2] acpi based pci gap caluculation v2

[Alok Kataria <akataria@vmware.com>]

On Wed, 2008-06-25 at 09:57 -0700, Alok Kataria wrote:

> While writing this mail i figured out that, instead of searching from
> start_addr of _CRS to 2^32 we should just search till *end_addr* of _CRS resource.
> I will send a patch to that effect. 
> 
> Thanks,
> Alok
> 

Ingo, Please also apply this patch to the tip/out-of-tree
--

Incremental patch . This patch passes the pci producer resources
end_addr (got from _CRS) to the e820_search_gap function. 
Without this patch the code will always search from the producer regions
start_address to 2^32, even though the producer region may be smaller. 

Now , we limit the search only within the producer region's address
space. 
Also we put a condition to check if the resource lies in the 32bit
address range. 

Signed-off-by: Alok N Kataria <akataria@vmware.com>

Index: linux-x86-tree.git/arch/x86/pci/acpi.c
===================================================================
--- linux-x86-tree.git.orig/arch/x86/pci/acpi.c	2008-06-25 10:11:35.000000000 -0700
+++ linux-x86-tree.git/arch/x86/pci/acpi.c	2008-06-25 11:17:31.000000000 -0700
@@ -121,13 +121,21 @@
 	struct acpi_resource_address64 addr;
 	acpi_status status;
 	struct gap_info *gap = data;
+	unsigned long long start_addr, end_addr;
 
 	status = resource_to_addr(resource, &addr);
 	if (ACPI_SUCCESS(status) &&
 	    addr.resource_type == ACPI_MEMORY_RANGE &&
 	    addr.address_length > gap->gapsize) {
-		e820_search_gap(&gap->gapstart, &gap->gapsize,
-				(addr.minimum + addr.translation_offset));
+		start_addr = addr.minimum + addr.translation_offset;
+		/*
+		 * We want space only in the 32bit address range
+		 */
+		if (start_addr < UINT_MAX) {
+			end_addr = start_addr + addr.address_length;
+			e820_search_gap(&gap->gapstart, &gap->gapsize,
+					start_addr, end_addr);
+		}
 	}
 
 	return AE_OK;