From a00cc7d9dd93d66a3fb83fc52aa57a4bec51c517 Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Fri, 24 Feb 2017 14:57:02 -0800 Subject: mm, x86: add support for PUD-sized transparent hugepages The current transparent hugepage code only supports PMDs. This patch adds support for transparent use of PUDs with DAX. It does not include support for anonymous pages. x86 support code also added. Most of this patch simply parallels the work that was done for huge PMDs. The only major difference is how the new ->pud_entry method in mm_walk works. The ->pmd_entry method replaces the ->pte_entry method, whereas the ->pud_entry method works along with either ->pmd_entry or ->pte_entry. The pagewalk code takes care of locking the PUD before calling ->pud_walk, so handlers do not need to worry whether the PUD is stable. [dave.jiang@intel.com: fix SMP x86 32bit build for native_pud_clear()] Link: http://lkml.kernel.org/r/148719066814.31111.3239231168815337012.stgit@djiang5-desk3.ch.intel.com [dave.jiang@intel.com: native_pud_clear missing on i386 build] Link: http://lkml.kernel.org/r/148640375195.69754.3315433724330910314.stgit@djiang5-desk3.ch.intel.com Link: http://lkml.kernel.org/r/148545059381.17912.8602162635537598445.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Matthew Wilcox Signed-off-by: Dave Jiang Tested-by: Alexander Kapshuk Cc: Dave Hansen Cc: Vlastimil Babka Cc: Jan Kara Cc: Dan Williams Cc: Ross Zwisler Cc: Kirill A. Shutemov Cc: Nilesh Choudhury Cc: Ingo Molnar Cc: "H. Peter Anvin" Cc: Thomas Gleixner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/pgtable-generic.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) (limited to 'mm/pgtable-generic.c') diff --git a/mm/pgtable-generic.c b/mm/pgtable-generic.c index 71c5f9109f2a..4ed5908c65b0 100644 --- a/mm/pgtable-generic.c +++ b/mm/pgtable-generic.c @@ -123,6 +123,20 @@ pmd_t pmdp_huge_clear_flush(struct vm_area_struct *vma, unsigned long address, flush_pmd_tlb_range(vma, address, address + HPAGE_PMD_SIZE); return pmd; } + +#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD +pud_t pudp_huge_clear_flush(struct vm_area_struct *vma, unsigned long address, + pud_t *pudp) +{ + pud_t pud; + + VM_BUG_ON(address & ~HPAGE_PUD_MASK); + VM_BUG_ON(!pud_trans_huge(*pudp) && !pud_devmap(*pudp)); + pud = pudp_huge_get_and_clear(vma->vm_mm, address, pudp); + flush_pud_tlb_range(vma, address, address + HPAGE_PUD_SIZE); + return pud; +} +#endif #endif #ifndef __HAVE_ARCH_PGTABLE_DEPOSIT -- cgit