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| author | Dave Jiang <dave.jiang@intel.com> | 2018-08-17 15:43:40 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-08-17 16:20:27 -0700 |
| commit | e1fb4a0864958fac2fb1b23f9f4562a9f90e3e8f (patch) | |
| tree | 58c58654235f9432d77f73cfc14a1e07ae7bbcc6 /mm/mlock.c | |
| parent | e36488c83b6d871b35dd555afb2d434bd61687cf (diff) | |
| download | lwn-e1fb4a0864958fac2fb1b23f9f4562a9f90e3e8f.tar.gz lwn-e1fb4a0864958fac2fb1b23f9f4562a9f90e3e8f.zip | |
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>
Diffstat (limited to 'mm/mlock.c')
| -rw-r--r-- | mm/mlock.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/mm/mlock.c b/mm/mlock.c index 74e5a6547c3d..41cc47e28ad6 100644 --- a/mm/mlock.c +++ b/mm/mlock.c @@ -527,7 +527,8 @@ static int mlock_fixup(struct vm_area_struct *vma, struct vm_area_struct **prev, vm_flags_t old_flags = vma->vm_flags; if (newflags == vma->vm_flags || (vma->vm_flags & VM_SPECIAL) || - is_vm_hugetlb_page(vma) || vma == get_gate_vma(current->mm)) + is_vm_hugetlb_page(vma) || vma == get_gate_vma(current->mm) || + vma_is_dax(vma)) /* don't set VM_LOCKED or VM_LOCKONFAULT and don't count */ goto out; |