Re: [PATCH] x86/pci: claim SR-IOV bar in pcibios_allocate_resource

From: Yinghai Lu
Date: Tue Nov 24 2009 - 16:24:26 EST


Jesse Barnes wrote:
> On Sat, 14 Nov 2009 23:46:46 -0800
> Yinghai Lu <yinghai@xxxxxxxxxx> wrote:
>
>> so use correct allocation from BIOS, instead of later assign another
>> one.
>>
>> Signed-off-by: Yinghai Lu <yinghai@xxxxxxxxxx>
>>
>> ---
>> arch/x86/pci/i386.c | 4 +++-
>> 1 file changed, 3 insertions(+), 1 deletion(-)
>>
>> Index: linux-2.6/arch/x86/pci/i386.c
>> ===================================================================
>> --- linux-2.6.orig/arch/x86/pci/i386.c
>> +++ linux-2.6/arch/x86/pci/i386.c
>> @@ -155,7 +155,9 @@ static void __init pcibios_allocate_reso
>>
>> for_each_pci_dev(dev) {
>> pci_read_config_word(dev, PCI_COMMAND, &command);
>> - for (idx = 0; idx < PCI_ROM_RESOURCE; idx++) {
>> + for (idx = 0; idx < PCI_BRIDGE_RESOURCES; idx++) {
>> + if (idx == PCI_ROM_RESOURCE)
>> + continue;
>> r = &dev->resource[idx];
>> if (r->parent) /* Already
>> allocated */ continue;
>
> I'm worried this might have side effects beyond just allocating SR-IOV
> BARs, since it looks like we'll walk through all the bridge resources
> all the time?

/*
* For PCI devices, the region numbers are assigned this way:
*/
enum {
/* #0-5: standard PCI resources */
PCI_STD_RESOURCES,
PCI_STD_RESOURCE_END = 5,

/* #6: expansion ROM resource */
PCI_ROM_RESOURCE,

/* device specific resources */
#ifdef CONFIG_PCI_IOV
PCI_IOV_RESOURCES,
PCI_IOV_RESOURCE_END = PCI_IOV_RESOURCES + PCI_SRIOV_NUM_BARS - 1,
#endif

/* resources assigned to buses behind the bridge */
#define PCI_BRIDGE_RESOURCE_NUM 4

PCI_BRIDGE_RESOURCES,

so will only add IOV BAR related.

YH
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/