Prompted by a recent change to add more protection around setting up
'vm_flags' for a dax vma [1], rework the implementation to remove the
requirement to set VM_MIXEDMAP and VM_HUGEPAGE.
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.
This patch series passes a run of the ndctl unit test suite and the
'mmap.sh' [2] test in particular. 'mmap.sh' tries to catch dependencies
on VM_MIXEDMAP and {pte,pmd}_devmap().
[1]: https://lkml.org/lkml/2017/9/25/638
[2]: https://github.com/pmem/ndctl/blob/master/test/mmap.sh
---
Dan Williams (3):
dax: disable filesystem dax on devices that do not map pages
dax: stop using VM_MIXEDMAP for dax
dax: stop using VM_HUGEPAGE for dax
drivers/dax/device.c | 1 -
drivers/dax/super.c | 7 +++++++
fs/ext2/file.c | 1 -
fs/ext4/file.c | 1 -
fs/xfs/xfs_file.c | 2 --
mm/huge_memory.c | 8 ++++----
mm/ksm.c | 3 +++
mm/madvise.c | 2 +-
mm/memory.c | 20 ++++++++++++++++++--
mm/migrate.c | 3 ++-
mm/mlock.c | 3 ++-
mm/mmap.c | 5 +++--
12 files changed, 40 insertions(+), 16 deletions(-)
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