PCI: Allocate 64-bit BARs above 4G when possible

Try to allocate space for 64-bit BARs above 4G first, to preserve the space
below 4G for 32-bit BARs.  If there's no space above 4G available, fall
back to allocating anywhere.

[bhelgaas: reworked starting from http://lkml.kernel.org/r/1387485843-17403-2-git-send-email-yinghai@kernel.org]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
This commit is contained in:
Yinghai Lu 2013-12-20 10:55:44 -07:00 committed by Bjorn Helgaas
parent f75b99d5a7
commit d56dbf5bab

View file

@ -102,6 +102,8 @@ static struct pci_bus_region pci_32_bit = {0, 0xffffffffULL};
#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
static struct pci_bus_region pci_64_bit = {0,
(dma_addr_t) 0xffffffffffffffffULL};
static struct pci_bus_region pci_high = {(dma_addr_t) 0x100000000ULL,
(dma_addr_t) 0xffffffffffffffffULL};
#endif
/*
@ -198,8 +200,7 @@ static int pci_bus_alloc_from_region(struct pci_bus *bus, struct resource *res,
* alignment and type, try to find an acceptable resource allocation
* for a specific device resource.
*/
int
pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
int pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
resource_size_t size, resource_size_t align,
resource_size_t min, unsigned int type_mask,
resource_size_t (*alignf)(void *,
@ -209,10 +210,19 @@ pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
void *alignf_data)
{
#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
if (res->flags & IORESOURCE_MEM_64)
int rc;
if (res->flags & IORESOURCE_MEM_64) {
rc = pci_bus_alloc_from_region(bus, res, size, align, min,
type_mask, alignf, alignf_data,
&pci_high);
if (rc == 0)
return 0;
return pci_bus_alloc_from_region(bus, res, size, align, min,
type_mask, alignf, alignf_data,
&pci_64_bit);
}
#endif
return pci_bus_alloc_from_region(bus, res, size, align, min,