From 83862ccfc0a03212fde43b4ac29c28381828768b Mon Sep 17 00:00:00 2001 From: Stefano Stabellini Date: Thu, 10 Oct 2013 13:40:44 +0000 Subject: [PATCH] xen/arm,arm64: enable SWIOTLB_XEN Xen on arm and arm64 needs SWIOTLB_XEN: when running on Xen we need to program the hardware with mfns rather than pfns for dma addresses. Remove SWIOTLB_XEN dependency on X86 and PCI and make XEN select SWIOTLB_XEN on arm and arm64. At the moment always rely on swiotlb-xen, but when Xen starts supporting hardware IOMMUs we'll be able to avoid it conditionally on the presence of an IOMMU on the platform. Implement xen_create_contiguous_region on arm and arm64: for the moment we assume that dom0 has been mapped 1:1 (physical addresses == machine addresses) therefore we don't need to call XENMEM_exchange. Simply return the physical address as dma address. Initialize the xen-swiotlb from xen_early_init (before the native dma_ops are initialized), set xen_dma_ops to &xen_swiotlb_dma_ops. Signed-off-by: Stefano Stabellini Changes in v8: - assume dom0 is mapped 1:1, no need to call XENMEM_exchange. Changes in v7: - call __set_phys_to_machine_multi from xen_create_contiguous_region and xen_destroy_contiguous_region to update the P2M; - don't call XENMEM_unpin, it has been removed; - call XENMEM_exchange instead of XENMEM_exchange_and_pin; - set nr_exchanged to 0 before calling the hypercall. Changes in v6: - introduce and export xen_dma_ops; - call xen_mm_init from as arch_initcall. Changes in v4: - remove redefinition of DMA_ERROR_CODE; - update the code to use XENMEM_exchange_and_pin and XENMEM_unpin; - add a note about hardware IOMMU in the commit message. Changes in v3: - code style changes; - warn on XENMEM_put_dma_buf failures. --- arch/arm/Kconfig | 1 + arch/arm/include/asm/xen/hypervisor.h | 2 + arch/arm/include/asm/xen/page.h | 1 + arch/arm/xen/Makefile | 2 +- arch/arm/xen/mm.c | 64 +++++++++++++++++++++++++++ arch/arm64/Kconfig | 1 + arch/arm64/xen/Makefile | 2 +- drivers/xen/Kconfig | 1 - drivers/xen/swiotlb-xen.c | 15 +++++++ 9 files changed, 86 insertions(+), 3 deletions(-) create mode 100644 arch/arm/xen/mm.c diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index b08374f8fe3b..01f7013c85c7 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -1888,6 +1888,7 @@ config XEN depends on CPU_V7 && !CPU_V6 depends on !GENERIC_ATOMIC64 select ARM_PSCI + select SWIOTLB_XEN help Say Y if you want to run Linux in a Virtual Machine on Xen on ARM. diff --git a/arch/arm/include/asm/xen/hypervisor.h b/arch/arm/include/asm/xen/hypervisor.h index d7ab99a0c9eb..1317ee40f4df 100644 --- a/arch/arm/include/asm/xen/hypervisor.h +++ b/arch/arm/include/asm/xen/hypervisor.h @@ -16,4 +16,6 @@ static inline enum paravirt_lazy_mode paravirt_get_lazy_mode(void) return PARAVIRT_LAZY_NONE; } +extern struct dma_map_ops *xen_dma_ops; + #endif /* _ASM_ARM_XEN_HYPERVISOR_H */ diff --git a/arch/arm/include/asm/xen/page.h b/arch/arm/include/asm/xen/page.h index d1b5dd566472..5d0e4c5dc711 100644 --- a/arch/arm/include/asm/xen/page.h +++ b/arch/arm/include/asm/xen/page.h @@ -6,6 +6,7 @@ #include #include +#include #include #include diff --git a/arch/arm/xen/Makefile b/arch/arm/xen/Makefile index 21e6ff503178..12969523414c 100644 --- a/arch/arm/xen/Makefile +++ b/arch/arm/xen/Makefile @@ -1 +1 @@ -obj-y := enlighten.o hypercall.o grant-table.o p2m.o +obj-y := enlighten.o hypercall.o grant-table.o p2m.o mm.o diff --git a/arch/arm/xen/mm.c b/arch/arm/xen/mm.c new file mode 100644 index 000000000000..d56b8c6e4fbb --- /dev/null +++ b/arch/arm/xen/mm.c @@ -0,0 +1,64 @@ +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include + +#include +#include +#include +#include + +int xen_create_contiguous_region(unsigned long vstart, unsigned int order, + unsigned int address_bits, + dma_addr_t *dma_handle) +{ + if (!xen_initial_domain()) + return -EINVAL; + + /* we assume that dom0 is mapped 1:1 for now */ + *dma_handle = virt_to_phys(pstart); + return 0; +} +EXPORT_SYMBOL_GPL(xen_create_contiguous_region); + +void xen_destroy_contiguous_region(unsigned long vstart, unsigned int order) +{ + return; +} +EXPORT_SYMBOL_GPL(xen_destroy_contiguous_region); + +struct dma_map_ops *xen_dma_ops; +EXPORT_SYMBOL_GPL(xen_dma_ops); + +static struct dma_map_ops xen_swiotlb_dma_ops = { + .mapping_error = xen_swiotlb_dma_mapping_error, + .alloc = xen_swiotlb_alloc_coherent, + .free = xen_swiotlb_free_coherent, + .sync_single_for_cpu = xen_swiotlb_sync_single_for_cpu, + .sync_single_for_device = xen_swiotlb_sync_single_for_device, + .sync_sg_for_cpu = xen_swiotlb_sync_sg_for_cpu, + .sync_sg_for_device = xen_swiotlb_sync_sg_for_device, + .map_sg = xen_swiotlb_map_sg_attrs, + .unmap_sg = xen_swiotlb_unmap_sg_attrs, + .map_page = xen_swiotlb_map_page, + .unmap_page = xen_swiotlb_unmap_page, + .dma_supported = xen_swiotlb_dma_supported, +}; + +int __init xen_mm_init(void) +{ + if (!xen_initial_domain()) + return 0; + xen_swiotlb_init(1, false); + xen_dma_ops = &xen_swiotlb_dma_ops; + return 0; +} +arch_initcall(xen_mm_init); diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index c04454876bcb..04ffafb6fbe9 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -211,6 +211,7 @@ config XEN_DOM0 config XEN bool "Xen guest support on ARM64 (EXPERIMENTAL)" depends on ARM64 && OF + select SWIOTLB_XEN help Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64. diff --git a/arch/arm64/xen/Makefile b/arch/arm64/xen/Makefile index cd866b0c619b..74a8d87e542b 100644 --- a/arch/arm64/xen/Makefile +++ b/arch/arm64/xen/Makefile @@ -1,2 +1,2 @@ -xen-arm-y += $(addprefix ../../arm/xen/, enlighten.o grant-table.o p2m.o) +xen-arm-y += $(addprefix ../../arm/xen/, enlighten.o grant-table.o p2m.o mm.o) obj-y := xen-arm.o hypercall.o diff --git a/drivers/xen/Kconfig b/drivers/xen/Kconfig index 23eae5cb69c2..c794ea182140 100644 --- a/drivers/xen/Kconfig +++ b/drivers/xen/Kconfig @@ -140,7 +140,6 @@ config XEN_GRANT_DEV_ALLOC config SWIOTLB_XEN def_bool y - depends on PCI && X86 select SWIOTLB config XEN_TMEM diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c index b72f31c1e018..f0fc1a4f565a 100644 --- a/drivers/xen/swiotlb-xen.c +++ b/drivers/xen/swiotlb-xen.c @@ -42,12 +42,27 @@ #include #include #include +#include /* * Used to do a quick range check in swiotlb_tbl_unmap_single and * swiotlb_tbl_sync_single_*, to see if the memory was in fact allocated by this * API. */ +#ifndef CONFIG_X86 +static unsigned long dma_alloc_coherent_mask(struct device *dev, + gfp_t gfp) +{ + unsigned long dma_mask = 0; + + dma_mask = dev->coherent_dma_mask; + if (!dma_mask) + dma_mask = (gfp & GFP_DMA) ? DMA_BIT_MASK(24) : DMA_BIT_MASK(32); + + return dma_mask; +} +#endif + static char *xen_io_tlb_start, *xen_io_tlb_end; static unsigned long xen_io_tlb_nslabs; /* -- GitLab