On Mon, Oct 02, 2017 at 06:30:41PM +0800, Miles Chen wrote: > ARCHs like metag and xtensa define their mappings (non-vmalloc and > non-linear) for dma allocation. metag basically is a reimplementation of the vmalloc map mechanism that should be easy to consolidate into the common one :( xtensa has a weird remapping into a different segment, something that I vaguely remember mips used to support as well. > These mapping types are architecture-dependent and should not be used > outside arch folders. So it is hard to check the mappings and convert > a virtual address to a correct pfn in lib/dam-debug.c > > How about recording only vmalloc (by is_vmalloc_addr()) and linear > address (by virt_addr_valid()) in lib/dma-debug? Since current > implementation is not correct for those ARCHs. > > if (!is_vmalloc_addr(addr) && !virt_addr_valid(addr)) > return; > > or This looks like a good start, although I'm not sure I'd trust virt_addr_valid on every little arch. In the worse case we'll have to exclude offenders from supporting dma debug, so let's go with that version. > > > > + entry->pfn = is_vmalloc_addr(virt) ? vmalloc_to_pfn(virt) : > > > > + page_to_pfn(virt_to_page(virt)); > > > > Please use normal if/else conditionsals: > > Is this for better readability? I'll send another patch for this. Yes. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
