diff options
author | Dave Jiang <dave.jiang@intel.com> | 2018-08-18 01:43:40 +0300 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-08-18 02:20:27 +0300 |
commit | e1fb4a0864958fac2fb1b23f9f4562a9f90e3e8f (patch) | |
tree | 58c58654235f9432d77f73cfc14a1e07ae7bbcc6 /mm/hmm.c | |
parent | e36488c83b6d871b35dd555afb2d434bd61687cf (diff) | |
download | linux-e1fb4a0864958fac2fb1b23f9f4562a9f90e3e8f.tar.xz |
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/hmm.c')
-rw-r--r-- | mm/hmm.c | 6 |
1 files changed, 4 insertions, 2 deletions
@@ -676,7 +676,8 @@ int hmm_vma_get_pfns(struct hmm_range *range) return -EINVAL; /* FIXME support hugetlb fs */ - if (is_vm_hugetlb_page(vma) || (vma->vm_flags & VM_SPECIAL)) { + if (is_vm_hugetlb_page(vma) || (vma->vm_flags & VM_SPECIAL) || + vma_is_dax(vma)) { hmm_pfns_special(range); return -EINVAL; } @@ -849,7 +850,8 @@ int hmm_vma_fault(struct hmm_range *range, bool block) return -EINVAL; /* FIXME support hugetlb fs */ - if (is_vm_hugetlb_page(vma) || (vma->vm_flags & VM_SPECIAL)) { + if (is_vm_hugetlb_page(vma) || (vma->vm_flags & VM_SPECIAL) || + vma_is_dax(vma)) { hmm_pfns_special(range); return -EINVAL; } |