diff options
author | Stefano Stabellini <stefano.stabellini@eu.citrix.com> | 2013-10-10 09:40:44 -0400 |
---|---|---|
committer | Stefano Stabellini <stefano.stabellini@eu.citrix.com> | 2013-10-10 09:40:44 -0400 |
commit | 83862ccfc0a03212fde43b4ac29c28381828768b (patch) | |
tree | f750d82b6d3162d066687d55de2bce0cf48e0b43 /arch/arm/xen/mm.c | |
parent | 69908907b02efee31377af0cefbcd5a3ba66334a (diff) |
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/mm.c')
-rw-r--r-- | arch/arm/xen/mm.c | 64 |
1 files changed, 64 insertions, 0 deletions
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 @@ | |||
1 | #include <linux/bootmem.h> | ||
2 | #include <linux/gfp.h> | ||
3 | #include <linux/export.h> | ||
4 | #include <linux/slab.h> | ||
5 | #include <linux/types.h> | ||
6 | #include <linux/dma-mapping.h> | ||
7 | #include <linux/vmalloc.h> | ||
8 | #include <linux/swiotlb.h> | ||
9 | |||
10 | #include <xen/xen.h> | ||
11 | #include <xen/interface/memory.h> | ||
12 | #include <xen/swiotlb-xen.h> | ||
13 | |||
14 | #include <asm/cacheflush.h> | ||
15 | #include <asm/xen/page.h> | ||
16 | #include <asm/xen/hypercall.h> | ||
17 | #include <asm/xen/interface.h> | ||
18 | |||
19 | int xen_create_contiguous_region(unsigned long vstart, unsigned int order, | ||
20 | unsigned int address_bits, | ||
21 | dma_addr_t *dma_handle) | ||
22 | { | ||
23 | if (!xen_initial_domain()) | ||
24 | return -EINVAL; | ||
25 | |||
26 | /* we assume that dom0 is mapped 1:1 for now */ | ||
27 | *dma_handle = virt_to_phys(pstart); | ||
28 | return 0; | ||
29 | } | ||
30 | EXPORT_SYMBOL_GPL(xen_create_contiguous_region); | ||
31 | |||
32 | void xen_destroy_contiguous_region(unsigned long vstart, unsigned int order) | ||
33 | { | ||
34 | return; | ||
35 | } | ||
36 | EXPORT_SYMBOL_GPL(xen_destroy_contiguous_region); | ||
37 | |||
38 | struct dma_map_ops *xen_dma_ops; | ||
39 | EXPORT_SYMBOL_GPL(xen_dma_ops); | ||
40 | |||
41 | static struct dma_map_ops xen_swiotlb_dma_ops = { | ||
42 | .mapping_error = xen_swiotlb_dma_mapping_error, | ||
43 | .alloc = xen_swiotlb_alloc_coherent, | ||
44 | .free = xen_swiotlb_free_coherent, | ||
45 | .sync_single_for_cpu = xen_swiotlb_sync_single_for_cpu, | ||
46 | .sync_single_for_device = xen_swiotlb_sync_single_for_device, | ||
47 | .sync_sg_for_cpu = xen_swiotlb_sync_sg_for_cpu, | ||
48 | .sync_sg_for_device = xen_swiotlb_sync_sg_for_device, | ||
49 | .map_sg = xen_swiotlb_map_sg_attrs, | ||
50 | .unmap_sg = xen_swiotlb_unmap_sg_attrs, | ||
51 | .map_page = xen_swiotlb_map_page, | ||
52 | .unmap_page = xen_swiotlb_unmap_page, | ||
53 | .dma_supported = xen_swiotlb_dma_supported, | ||
54 | }; | ||
55 | |||
56 | int __init xen_mm_init(void) | ||
57 | { | ||
58 | if (!xen_initial_domain()) | ||
59 | return 0; | ||
60 | xen_swiotlb_init(1, false); | ||
61 | xen_dma_ops = &xen_swiotlb_dma_ops; | ||
62 | return 0; | ||
63 | } | ||
64 | arch_initcall(xen_mm_init); | ||