linux/drivers/dax
Dave Jiang e1fb4a0864 dax: remove VM_MIXEDMAP for fsdax and device dax
This patch is reworked from an earlier patch that Dan has posted:
https://patchwork.kernel.org/patch/10131727/

VM_MIXEDMAP is used by dax to direct mm paths like vm_normal_page() that
the memory page it is dealing with is not typical memory from the linear
map.  The get_user_pages_fast() path, since it does not resolve the vma,
is already using {pte,pmd}_devmap() as a stand-in for VM_MIXEDMAP, so we
use that as a VM_MIXEDMAP replacement in some locations.  In the cases
where there is no pte to consult we fallback to using vma_is_dax() to
detect the VM_MIXEDMAP special case.

Now that we have explicit driver pfn_t-flag opt-in/opt-out for
get_user_pages() support for DAX we can stop setting VM_MIXEDMAP.  This
also means we no longer need to worry about safely manipulating vm_flags
in a future where we support dynamically changing the dax mode of a
file.

DAX should also now be supported with madvise_behavior(), vma_merge(),
and copy_page_range().

This patch has been tested against ndctl unit test.  It has also been
tested against xfstests commit: 625515d using fake pmem created by
memmap and no additional issues have been observed.

Link: http://lkml.kernel.org/r/152847720311.55924.16999195879201817653.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-17 16:20:27 -07:00
..
Kconfig dax: introduce CONFIG_DAX_DRIVER 2018-04-03 05:41:19 -07:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
dax-private.h Merge branch 'for-4.12/dax' into libnvdimm-for-next 2017-05-04 23:38:43 -07:00
dax.h pmem: add dax_operations support 2017-04-19 15:14:35 -07:00
device-dax.h device-dax: fix sysfs duplicate warnings 2017-07-18 17:49:14 -07:00
device.c dax: remove VM_MIXEDMAP for fsdax and device dax 2018-08-17 16:20:27 -07:00
pmem.c device-dax: use module_nd_driver 2018-03-15 07:18:47 -07:00
super.c dax: check for QUEUE_FLAG_DAX in bdev_dax_supported() 2018-06-28 16:06:08 -04:00