On Mon, Aug 19, 2019 at 12:45:17PM +0100, Julien Grall wrote: > On 8/16/19 2:00 PM, Christoph Hellwig wrote: >> +static inline void 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) >> +{ >> + unsigned long page_pfn = page_to_xen_pfn(page); >> + unsigned long dev_pfn = XEN_PFN_DOWN(dev_addr); >> + unsigned long compound_pages = >> + (1<<compound_order(page)) * XEN_PFN_PER_PAGE; >> + bool local = (page_pfn <= dev_pfn) && >> + (dev_pfn - page_pfn < compound_pages); >> + > > The Arm version as a comment here. Could we retain it?
I've added it in this patch, altough the rewrites later on mean it will go away in favour of a new comment elsewhere anyway.