1. 25 Oct, 2013 2 commits
  2. 10 Oct, 2013 1 commit
    • Stefano Stabellini's avatar
      swiotlb-xen: use xen_alloc/free_coherent_pages · 1b65c4e5
      Stefano Stabellini authored
      Use xen_alloc_coherent_pages and xen_free_coherent_pages to allocate or
      free coherent pages.
      
      We need to be careful handling the pointer returned by
      xen_alloc_coherent_pages, because on ARM the pointer is not equal to
      phys_to_virt(*dma_handle). In fact virt_to_phys only works for kernel
      direct mapped RAM memory.
      In ARM case the pointer could be an ioremap address, therefore passing
      it to virt_to_phys would give you another physical address that doesn't
      correspond to it.
      
      Make xen_create_contiguous_region take a phys_addr_t as start parameter to
      avoid the virt_to_phys calls which would be incorrect.
      
      Changes in v6:
      - remove extra spaces.
      Signed-off-by: default avatarStefano Stabellini <stefano.stabellini@eu.citrix.com>
      Reviewed-by: default avatarKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
      1b65c4e5
  3. 09 Oct, 2013 1 commit
    • Stefano Stabellini's avatar
      xen: introduce xen_alloc/free_coherent_pages · d6fe76c5
      Stefano Stabellini authored
      xen_swiotlb_alloc_coherent needs to allocate a coherent buffer for cpu
      and devices. On native x86 is sufficient to call __get_free_pages in
      order to get a coherent buffer, while on ARM (and potentially ARM64) we
      need to call the native dma_ops->alloc implementation.
      
      Introduce xen_alloc_coherent_pages to abstract the arch specific buffer
      allocation.
      
      Similarly introduce xen_free_coherent_pages to free a coherent buffer:
      on x86 is simply a call to free_pages while on ARM and ARM64 is
      arm_dma_ops.free.
      Signed-off-by: default avatarStefano Stabellini <stefano.stabellini@eu.citrix.com>
      
      
      Changes in v7:
      - rename __get_dma_ops to __generic_dma_ops;
      - call __generic_dma_ops(hwdev)->alloc/free on arm64 too.
      
      Changes in v6:
      - call __get_dma_ops to get the native dma_ops pointer on arm.
      d6fe76c5
  4. 18 Oct, 2013 2 commits
  5. 09 Oct, 2013 1 commit
  6. 10 Oct, 2013 1 commit
    • Stefano Stabellini's avatar
      xen/arm,arm64: enable SWIOTLB_XEN · 83862ccf
      Stefano Stabellini authored
      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: default avatarStefano 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.
      83862ccf
  7. 09 Oct, 2013 2 commits
  8. 17 Oct, 2013 1 commit
    • Stefano Stabellini's avatar
      arm/xen,arm64/xen: introduce p2m · 4a19138c
      Stefano Stabellini authored
      Introduce physical to machine and machine to physical tracking
      mechanisms based on rbtrees for arm/xen and arm64/xen.
      
      We need it because any guests on ARM are an autotranslate guests,
      therefore a physical address is potentially different from a machine
      address. When programming a device to do DMA, we need to be
      extra-careful to use machine addresses rather than physical addresses to
      program the device. Therefore we need to know the physical to machine
      mappings.
      
      For the moment we assume that dom0 starts with a 1:1 physical to machine
      mapping, in other words physical addresses correspond to machine
      addresses. However when mapping a foreign grant reference, obviously the
      1:1 model doesn't work anymore. So at the very least we need to be able
      to track grant mappings.
      
      We need locking to protect accesses to the two trees.
      Signed-off-by: default avatarStefano Stabellini <stefano.stabellini@eu.citrix.com>
      
      Changes in v8:
      - move pfn_to_mfn and mfn_to_pfn to page.h as static inline functions;
      - no need to walk the tree if phys_to_mach.rb_node is NULL;
      - correctly handle multipage p2m entries;
      - substitute the spin_lock with a rwlock.
      4a19138c
  9. 15 Oct, 2013 2 commits
  10. 13 Oct, 2013 17 commits
  11. 12 Oct, 2013 10 commits