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| author | Dave Jiang <[email protected]> | 2018-08-17 22:43:40 +0000 |
|---|---|---|
| committer | Linus Torvalds <[email protected]> | 2018-08-17 23:20:27 +0000 |
| commit | e1fb4a0864958fac2fb1b23f9f4562a9f90e3e8f (patch) | |
| tree | 58c58654235f9432d77f73cfc14a1e07ae7bbcc6 /mm/migrate.c | |
| parent | bitfield: avoid gcc-8 -Wint-in-bool-context warning (diff) | |
| download | kernel-e1fb4a0864958fac2fb1b23f9f4562a9f90e3e8f.tar.gz kernel-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 <[email protected]>
Acked-by: Dan Williams <[email protected]>
Cc: Jan Kara <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Diffstat (limited to 'mm/migrate.c')
| -rw-r--r-- | mm/migrate.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/mm/migrate.c b/mm/migrate.c index 8c0af0f7cab1..4a83268e23c2 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -2951,7 +2951,8 @@ int migrate_vma(const struct migrate_vma_ops *ops, /* Sanity check the arguments */ start &= PAGE_MASK; end &= PAGE_MASK; - if (!vma || is_vm_hugetlb_page(vma) || (vma->vm_flags & VM_SPECIAL)) + if (!vma || is_vm_hugetlb_page(vma) || (vma->vm_flags & VM_SPECIAL) || + vma_is_dax(vma)) return -EINVAL; if (start < vma->vm_start || start >= vma->vm_end) return -EINVAL; |