1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_ARM_XEN_PAGE_COHERENT_H
3 #define _ASM_ARM_XEN_PAGE_COHERENT_H
4
5 #include <asm/page.h>
6 #include <asm/dma-mapping.h>
7 #include <linux/dma-mapping.h>
8
xen_get_dma_ops(struct device * dev)9 static inline const struct dma_map_ops *xen_get_dma_ops(struct device *dev)
10 {
11 if (dev && dev->archdata.dev_dma_ops)
12 return dev->archdata.dev_dma_ops;
13 return get_arch_dma_ops(NULL);
14 }
15
16 void __xen_dma_map_page(struct device *hwdev, struct page *page,
17 dma_addr_t dev_addr, unsigned long offset, size_t size,
18 enum dma_data_direction dir, unsigned long attrs);
19 void __xen_dma_unmap_page(struct device *hwdev, dma_addr_t handle,
20 size_t size, enum dma_data_direction dir,
21 unsigned long attrs);
22 void __xen_dma_sync_single_for_cpu(struct device *hwdev,
23 dma_addr_t handle, size_t size, enum dma_data_direction dir);
24
25 void __xen_dma_sync_single_for_device(struct device *hwdev,
26 dma_addr_t handle, size_t size, enum dma_data_direction dir);
27
xen_alloc_coherent_pages(struct device * hwdev,size_t size,dma_addr_t * dma_handle,gfp_t flags,unsigned long attrs)28 static inline void *xen_alloc_coherent_pages(struct device *hwdev, size_t size,
29 dma_addr_t *dma_handle, gfp_t flags, unsigned long attrs)
30 {
31 return xen_get_dma_ops(hwdev)->alloc(hwdev, size, dma_handle, flags, attrs);
32 }
33
xen_free_coherent_pages(struct device * hwdev,size_t size,void * cpu_addr,dma_addr_t dma_handle,unsigned long attrs)34 static inline void xen_free_coherent_pages(struct device *hwdev, size_t size,
35 void *cpu_addr, dma_addr_t dma_handle, unsigned long attrs)
36 {
37 xen_get_dma_ops(hwdev)->free(hwdev, size, cpu_addr, dma_handle, attrs);
38 }
39
xen_dma_map_page(struct device * hwdev,struct page * page,dma_addr_t dev_addr,unsigned long offset,size_t size,enum dma_data_direction dir,unsigned long attrs)40 static inline void xen_dma_map_page(struct device *hwdev, struct page *page,
41 dma_addr_t dev_addr, unsigned long offset, size_t size,
42 enum dma_data_direction dir, unsigned long attrs)
43 {
44 unsigned long page_pfn = page_to_xen_pfn(page);
45 unsigned long dev_pfn = XEN_PFN_DOWN(dev_addr);
46 unsigned long compound_pages =
47 (1<<compound_order(page)) * XEN_PFN_PER_PAGE;
48 bool local = (page_pfn <= dev_pfn) &&
49 (dev_pfn - page_pfn < compound_pages);
50
51 /*
52 * Dom0 is mapped 1:1, while the Linux page can span across
53 * multiple Xen pages, it's not possible for it to contain a
54 * mix of local and foreign Xen pages. So if the first xen_pfn
55 * == mfn the page is local otherwise it's a foreign page
56 * grant-mapped in dom0. If the page is local we can safely
57 * call the native dma_ops function, otherwise we call the xen
58 * specific function.
59 */
60 if (local)
61 xen_get_dma_ops(hwdev)->map_page(hwdev, page, offset, size, dir, attrs);
62 else
63 __xen_dma_map_page(hwdev, page, dev_addr, offset, size, dir, attrs);
64 }
65
xen_dma_unmap_page(struct device * hwdev,dma_addr_t handle,size_t size,enum dma_data_direction dir,unsigned long attrs)66 static inline void xen_dma_unmap_page(struct device *hwdev, dma_addr_t handle,
67 size_t size, enum dma_data_direction dir, unsigned long attrs)
68 {
69 unsigned long pfn = PFN_DOWN(handle);
70 /*
71 * Dom0 is mapped 1:1, while the Linux page can be spanned accross
72 * multiple Xen page, it's not possible to have a mix of local and
73 * foreign Xen page. Dom0 is mapped 1:1, so calling pfn_valid on a
74 * foreign mfn will always return false. If the page is local we can
75 * safely call the native dma_ops function, otherwise we call the xen
76 * specific function.
77 */
78 if (pfn_valid(pfn)) {
79 if (xen_get_dma_ops(hwdev)->unmap_page)
80 xen_get_dma_ops(hwdev)->unmap_page(hwdev, handle, size, dir, attrs);
81 } else
82 __xen_dma_unmap_page(hwdev, handle, size, dir, attrs);
83 }
84
xen_dma_sync_single_for_cpu(struct device * hwdev,dma_addr_t handle,size_t size,enum dma_data_direction dir)85 static inline void xen_dma_sync_single_for_cpu(struct device *hwdev,
86 dma_addr_t handle, size_t size, enum dma_data_direction dir)
87 {
88 unsigned long pfn = PFN_DOWN(handle);
89 if (pfn_valid(pfn)) {
90 if (xen_get_dma_ops(hwdev)->sync_single_for_cpu)
91 xen_get_dma_ops(hwdev)->sync_single_for_cpu(hwdev, handle, size, dir);
92 } else
93 __xen_dma_sync_single_for_cpu(hwdev, handle, size, dir);
94 }
95
xen_dma_sync_single_for_device(struct device * hwdev,dma_addr_t handle,size_t size,enum dma_data_direction dir)96 static inline void xen_dma_sync_single_for_device(struct device *hwdev,
97 dma_addr_t handle, size_t size, enum dma_data_direction dir)
98 {
99 unsigned long pfn = PFN_DOWN(handle);
100 if (pfn_valid(pfn)) {
101 if (xen_get_dma_ops(hwdev)->sync_single_for_device)
102 xen_get_dma_ops(hwdev)->sync_single_for_device(hwdev, handle, size, dir);
103 } else
104 __xen_dma_sync_single_for_device(hwdev, handle, size, dir);
105 }
106
107 #endif /* _ASM_ARM_XEN_PAGE_COHERENT_H */
108