From d56dbf5bab8ce44c5407bb099f71987f58d18bb4 Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Fri, 20 Dec 2013 10:55:44 -0700 Subject: [PATCH] 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 Signed-off-by: Bjorn Helgaas --- drivers/pci/bus.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c index c30baae929f4..86fb8ec5e448 100644 --- a/drivers/pci/bus.c +++ b/drivers/pci/bus.c @@ -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, -- 2.20.1