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| author | Khalid Aziz <khalid.aziz@oracle.com> | 2018-02-21 10:15:44 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2018-03-18 07:38:45 -0700 |
| commit | ca827d55ebaa24de9fca36ee24e42d6fc5119ee3 (patch) | |
| tree | 12b0ff1c2705daaeeeb7fd4d5a0be63d7098016f /mm/rmap.c | |
| parent | d84bb709aa4a6a155b1aaaf449cad21f02be4594 (diff) | |
| download | lwn-ca827d55ebaa24de9fca36ee24e42d6fc5119ee3.tar.gz lwn-ca827d55ebaa24de9fca36ee24e42d6fc5119ee3.zip | |
mm, swap: Add infrastructure for saving page metadata on swap
If a processor supports special metadata for a page, for example ADI
version tags on SPARC M7, this metadata must be saved when the page is
swapped out. The same metadata must be restored when the page is swapped
back in. This patch adds two new architecture specific functions -
arch_do_swap_page() to be called when a page is swapped in, and
arch_unmap_one() to be called when a page is being unmapped for swap
out. These architecture hooks allow page metadata to be saved if the
architecture supports it.
Signed-off-by: Khalid Aziz <khalid.aziz@oracle.com>
Cc: Khalid Aziz <khalid@gonehiking.org>
Acked-by: Jerome Marchand <jmarchan@redhat.com>
Reviewed-by: Anthony Yznaga <anthony.yznaga@oracle.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'mm/rmap.c')
| -rw-r--r-- | mm/rmap.c | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/mm/rmap.c b/mm/rmap.c index 47db27f8049e..144c66e688a9 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1497,6 +1497,14 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma, (flags & (TTU_MIGRATION|TTU_SPLIT_FREEZE))) { swp_entry_t entry; pte_t swp_pte; + + if (arch_unmap_one(mm, vma, address, pteval) < 0) { + set_pte_at(mm, address, pvmw.pte, pteval); + ret = false; + page_vma_mapped_walk_done(&pvmw); + break; + } + /* * Store the pfn of the page in a special migration * pte. do_swap_page() will wait until the migration @@ -1556,6 +1564,12 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma, page_vma_mapped_walk_done(&pvmw); break; } + if (arch_unmap_one(mm, vma, address, pteval) < 0) { + set_pte_at(mm, address, pvmw.pte, pteval); + ret = false; + page_vma_mapped_walk_done(&pvmw); + break; + } if (list_empty(&mm->mmlist)) { spin_lock(&mmlist_lock); if (list_empty(&mm->mmlist)) |