[PATCH -V8 13/18] powerpc: Update gup_pmd_range to handle transparent hugepages
From: Aneesh Kumar K.V <hidden>
Date: 2013-05-12 16:14:44
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Michael Ellerman, Linus Torvalds
From: "Aneesh Kumar K.V" <redacted> Reviewed-by: David Gibson <redacted> Signed-off-by: Aneesh Kumar K.V <redacted> --- arch/powerpc/mm/gup.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/mm/gup.c b/arch/powerpc/mm/gup.c
index 4b921af..3d36fd7 100644
--- a/arch/powerpc/mm/gup.c
+++ b/arch/powerpc/mm/gup.c@@ -66,9 +66,20 @@ static int gup_pmd_range(pud_t pud, unsigned long addr, unsigned long end, pmd_t pmd = *pmdp; next = pmd_addr_end(addr, end); - if (pmd_none(pmd)) + /* + * The pmd_trans_splitting() check below explains why + * pmdp_splitting_flush has to flush the tlb, to stop + * this gup-fast code from running while we set the + * splitting bit in the pmd. Returning zero will take + * the slow path that will call wait_split_huge_page() + * if the pmd is still in splitting state. gup-fast + * can't because it has irq disabled and + * wait_split_huge_page() would never return as the + * tlb flush IPI wouldn't run. + */ + if (pmd_none(pmd) || pmd_trans_splitting(pmd)) return 0; - if (pmd_huge(pmd)) { + if (pmd_huge(pmd) || pmd_large(pmd)) { if (!gup_hugepte((pte_t *)pmdp, PMD_SIZE, addr, next, write, pages, nr)) return 0;
--
1.8.1.2