[PATCH] Add IORESOUCE_BUSY flag for System RAM (Re: [Question] How to represent SYSTEM_RAM in kerene

Yasunori Goto
2007-11-01T09:21:35Z

Hello.

I was asked from Kame-san to write this patch.

Please apply.

---------
i386 and x86-64 registers System RAM as IORESOURCE_MEM | IORESOURCE_BUSY.

But ia64 registers it as IORESOURCE_MEM only.
In addition, memory hotplug code registers new memory as IORESOURCE_MEM too.

This patch adds IORESOURCE_BUSY for them to avoid potential overlap mapping
by PCI device.

Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>

---
arch/ia64/kernel/efi.c | 6 ++----
mm/memory_hotplug.c | 2 +-
2 files changed, 3 insertions(+), 5 deletions(-)

Index: current/arch/ia64/kernel/efi.c
=================================--- current.orig/arch/ia64/kernel/efi.c 2007-11-01 15:24:05.000000000 +0900
+++ current/arch/ia64/kernel/efi.c 2007-11-01 15:24:18.000000000 +0900
@@ -1111,7 +1111,7 @@ efi_initialize_iomem_resources(struct re
if (md->num_pages = 0) /* should not happen */
continue;

- flags = IORESOURCE_MEM;
+ flags = IORESOURCE_MEM | IORESOURCE_BUSY;
switch (md->type) {

case EFI_MEMORY_MAPPED_IO:
@@ -1133,12 +1133,11 @@ efi_initialize_iomem_resources(struct re

case EFI_ACPI_MEMORY_NVS:
name = "ACPI Non-volatile Storage";
- flags |= IORESOURCE_BUSY;
break;

case EFI_UNUSABLE_MEMORY:
name = "reserved";
- flags |= IORESOURCE_BUSY | IORESOURCE_DISABLED;
+ flags |= IORESOURCE_DISABLED;
break;

case EFI_RESERVED_TYPE:
@@ -1147,7 +1146,6 @@ efi_initialize_iomem_resources(struct re
case EFI_ACPI_RECLAIM_MEMORY:
default:
name = "reserved";
- flags |= IORESOURCE_BUSY;
break;
}

Index: current/mm/memory_hotplug.c
=================================--- current.orig/mm/memory_hotplug.c 2007-11-01 15:24:16.000000000 +0900
+++ current/mm/memory_hotplug.c 2007-11-01 15:41:27.000000000 +0900
@@ -39,7 +39,7 @@ static struct resource *register_memory_
res->name = "System RAM";
res->start = start;
res->end = start + size - 1;
- res->flags = IORESOURCE_MEM;
+ res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
if (request_resource(&iomem_resource, res) < 0) {
printk("System RAM resource %llx - %llx cannot be added\n",
(unsigned long long)res->start, (unsigned long long)res->end);

--
Yasunori Goto