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author | Stefano Stabellini <stefano.stabellini@eu.citrix.com> | 2013-10-10 13:40:44 +0000 |
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committer | Stefano Stabellini <stefano.stabellini@eu.citrix.com> | 2013-10-10 13:40:44 +0000 |
commit | 83862ccfc0a03212fde43b4ac29c28381828768b (patch) | |
tree | f750d82b6d3162d066687d55de2bce0cf48e0b43 /arch/arm/xen | |
parent | 69908907b02efee31377af0cefbcd5a3ba66334a (diff) | |
download | linux-83862ccfc0a03212fde43b4ac29c28381828768b.tar.gz linux-83862ccfc0a03212fde43b4ac29c28381828768b.tar.bz2 linux-83862ccfc0a03212fde43b4ac29c28381828768b.zip |
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 <stefano.stabellini@eu.citrix.com>
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.
Diffstat (limited to 'arch/arm/xen')
-rw-r--r-- | arch/arm/xen/Makefile | 2 | ||||
-rw-r--r-- | arch/arm/xen/mm.c | 64 |
2 files changed, 65 insertions, 1 deletions
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 <linux/bootmem.h> +#include <linux/gfp.h> +#include <linux/export.h> +#include <linux/slab.h> +#include <linux/types.h> +#include <linux/dma-mapping.h> +#include <linux/vmalloc.h> +#include <linux/swiotlb.h> + +#include <xen/xen.h> +#include <xen/interface/memory.h> +#include <xen/swiotlb-xen.h> + +#include <asm/cacheflush.h> +#include <asm/xen/page.h> +#include <asm/xen/hypercall.h> +#include <asm/xen/interface.h> + +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); |