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path: root/arch/arm/xen/mm32.c
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2014-12-04xen/arm/arm64: merge xen/mm32.c into xen/mm.cStefano Stabellini
Merge xen/mm32.c into xen/mm.c. As a consequence the code gets compiled on arm64 too. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
2014-12-04xen/arm: use hypercall to flush caches in map_pageStefano Stabellini
In xen_dma_map_page, if the page is a local page, call the native map_page dma_ops. If the page is foreign, call __xen_dma_map_page that issues any required cache maintenane operations via hypercall. The reason for doing this is that the native dma_ops map_page could allocate buffers than need to be freed. If the page is foreign we don't call the native unmap_page dma_ops function, resulting in a memory leak. Suggested-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
2014-12-04xen/arm: use is_device_dma_coherentStefano Stabellini
Use is_device_dma_coherent to check whether we need to issue cache maintenance operations rather than checking on the existence of a particular dma_ops function for the device. This is correct because coherent devices don't need cache maintenance operations - arm_coherent_dma_ops does not set the hooks that we were previously checking for existance. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Ian Campbell <ian.campbell@citrix.com>
2014-12-04xen/arm: if(pfn_valid(pfn)) call native dma_opsStefano Stabellini
Remove code duplication in mm32.c by calling the native dma_ops if the page is a local page (not a foreign page). Use a simple pfn_valid(pfn) check to figure out if the page is local, exploiting the fact that dom0 is mapped 1:1, therefore pfn_valid always returns false when called on a foreign mfn. Suggested-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
2014-12-04xen/arm: remove outer_*_range callStefano Stabellini
Dom0 is not actually capable of issuing outer_inv_range or outer_clean_range calls. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Acked-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
2014-12-04xen/arm: remove handling of XENFEAT_grant_map_identityStefano Stabellini
The feature has been removed from Xen. Also Linux cannot use it on ARM32 without CONFIG_ARM_LPAE. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Acked-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
2014-09-11xen/arm: reimplement xen_dma_unmap_page & friendsStefano Stabellini
xen_dma_unmap_page, xen_dma_sync_single_for_cpu and xen_dma_sync_single_for_device are currently implemented by calling into the corresponding generic ARM implementation of these functions. In order to do this, firstly the dma_addr_t handle, that on Xen is a machine address, needs to be translated into a physical address. The operation is expensive and inaccurate, given that a single machine address can correspond to multiple physical addresses in one domain, because the same page can be granted multiple times by the frontend. To avoid this problem, we introduce a Xen specific implementation of xen_dma_unmap_page, xen_dma_sync_single_for_cpu and xen_dma_sync_single_for_device, that can operate on machine addresses directly. The new implementation relies on the fact that the hypervisor creates a second p2m mapping of any grant pages at physical address == machine address of the page for dom0. Therefore we can access memory at physical address == dma_addr_r handle and perform the cache flushing there. Some cache maintenance operations require a virtual address. Instead of using ioremap_cache, that is not safe in interrupt context, we allocate a per-cpu PAGE_KERNEL scratch page and we manually update the pte for it. arm64 doesn't need cache maintenance operations on unmap for now. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Tested-by: Denis Schneider <v1ne2go@gmail.com>