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author | Linus Torvalds <torvalds@linux-foundation.org> | 2017-03-07 10:23:17 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-03-07 10:23:17 -0800 |
commit | 8c2c8ed8b85d4012d26caf1c221c291c687d89f0 (patch) | |
tree | c28ac6bfc83c198b2a61515694d05ad22f2cc25a /drivers/xen/swiotlb-xen.c | |
parent | 304362a8bce1a5b7f9491be5a0643cd14a52364d (diff) | |
parent | 69369f52d28a34c84acb6f2a8a585e743441566a (diff) | |
download | op-kernel-dev-8c2c8ed8b85d4012d26caf1c221c291c687d89f0.zip op-kernel-dev-8c2c8ed8b85d4012d26caf1c221c291c687d89f0.tar.gz |
Merge branch 'stable/for-linus-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb
Pull swiotlb updates from Konrad Rzeszutek Wilk:
"Two tiny implementations of the DMA API for callback in ARM (for Xen)"
* 'stable/for-linus-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb:
swiotlb-xen: implement xen_swiotlb_get_sgtable callback
swiotlb-xen: implement xen_swiotlb_dma_mmap callback
Diffstat (limited to 'drivers/xen/swiotlb-xen.c')
-rw-r--r-- | drivers/xen/swiotlb-xen.c | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c index f8afc6d..e8cef1a 100644 --- a/drivers/xen/swiotlb-xen.c +++ b/drivers/xen/swiotlb-xen.c @@ -681,3 +681,50 @@ xen_swiotlb_set_dma_mask(struct device *dev, u64 dma_mask) return 0; } EXPORT_SYMBOL_GPL(xen_swiotlb_set_dma_mask); + +/* + * Create userspace mapping for the DMA-coherent memory. + * This function should be called with the pages from the current domain only, + * passing pages mapped from other domains would lead to memory corruption. + */ +int +xen_swiotlb_dma_mmap(struct device *dev, struct vm_area_struct *vma, + void *cpu_addr, dma_addr_t dma_addr, size_t size, + unsigned long attrs) +{ +#if defined(CONFIG_ARM) || defined(CONFIG_ARM64) + if (__generic_dma_ops(dev)->mmap) + return __generic_dma_ops(dev)->mmap(dev, vma, cpu_addr, + dma_addr, size, attrs); +#endif + return dma_common_mmap(dev, vma, cpu_addr, dma_addr, size); +} +EXPORT_SYMBOL_GPL(xen_swiotlb_dma_mmap); + +/* + * This function should be called with the pages from the current domain only, + * passing pages mapped from other domains would lead to memory corruption. + */ +int +xen_swiotlb_get_sgtable(struct device *dev, struct sg_table *sgt, + void *cpu_addr, dma_addr_t handle, size_t size, + unsigned long attrs) +{ +#if defined(CONFIG_ARM) || defined(CONFIG_ARM64) + if (__generic_dma_ops(dev)->get_sgtable) { +#if 0 + /* + * This check verifies that the page belongs to the current domain and + * is not one mapped from another domain. + * This check is for debug only, and should not go to production build + */ + unsigned long bfn = PHYS_PFN(dma_to_phys(dev, handle)); + BUG_ON (!page_is_ram(bfn)); +#endif + return __generic_dma_ops(dev)->get_sgtable(dev, sgt, cpu_addr, + handle, size, attrs); + } +#endif + return dma_common_get_sgtable(dev, sgt, cpu_addr, handle, size); +} +EXPORT_SYMBOL_GPL(xen_swiotlb_get_sgtable); |