[resend PATCH v2 28/33] x86, libnvdimm, dax: stop abusing __copy_user_nocache

2017-04-17 Thread Dan Williams
The pmem and nd_blk drivers both have need to copy data through the cpu cache to persistent memory. To date they have been abusing __copy_user_nocache through the memcpy_to_pmem abstraction, but this has several problems: * __copy_user_nocache does not guarantee that it will always avoid the cac

[PATCH v2 28/33] x86, libnvdimm, dax: stop abusing __copy_user_nocache

2017-04-14 Thread Dan Williams
The pmem and nd_blk drivers both have need to copy data through the cpu cache to persistent memory. To date they have been abusing __copy_user_nocache through the memcpy_to_pmem abstraction, but this has several problems: * __copy_user_nocache does not guarantee that it will always avoid the cac