From: Thomas Hellstrom <thellstrom@xxxxxxxxxx> For VM_PFNMAP and VM_MIXEDMAP vmas that want to support transhuge pages and -page table entries, introduce vma_is_special_huge() that takes the same codepaths as vma_is_dax(). The use of "special" follows the definition in memory.c, vm_normal_page(): "Special" mappings do not wish to be associated with a "struct page" (either it doesn't exist, or it exists but they don't want to touch it) For PAGE_SIZE pages, "special" is determined per page table entry to be able to deal with COW pages. But since we don't have huge COW pages, we can classify a vma as either "special huge" or "normal huge". Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxx> Cc: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx> Cc: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx> Cc: Ralph Campbell <rcampbell@xxxxxxxxxx> Cc: "Jérôme Glisse" <jglisse@xxxxxxxxxx> Cc: "Christian König" <christian.koenig@xxxxxxx> Signed-off-by: Thomas Hellstrom <thellstrom@xxxxxxxxxx> --- include/linux/mm.h | 6 ++++++ mm/huge_memory.c | 6 +++--- 2 files changed, 9 insertions(+), 3 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index 29575d3c1e47..1ee45ef306d8 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2838,6 +2838,12 @@ extern long copy_huge_page_from_user(struct page *dst_page, const void __user *usr_src, unsigned int pages_per_huge_page, bool allow_pagefault); +static inline bool vma_is_special_huge(struct vm_area_struct *vma) +{ + return vma_is_dax(vma) || (vma->vm_file && + (vma->vm_flags & (VM_PFNMAP | VM_MIXEDMAP))); +} + #endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_HUGETLBFS */ #ifdef CONFIG_DEBUG_PAGEALLOC diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 13cc93785006..3c83467f09b2 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1789,7 +1789,7 @@ int zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma, orig_pmd = pmdp_huge_get_and_clear_full(tlb->mm, addr, pmd, tlb->fullmm); tlb_remove_pmd_tlb_entry(tlb, pmd, addr); - if (vma_is_dax(vma)) { + if (vma_is_special_huge(vma)) { if (arch_needs_pgtable_deposit()) zap_deposited_table(tlb->mm, pmd); spin_unlock(ptl); @@ -2053,7 +2053,7 @@ int zap_huge_pud(struct mmu_gather *tlb, struct vm_area_struct *vma, */ pudp_huge_get_and_clear_full(tlb->mm, addr, pud, tlb->fullmm); tlb_remove_pud_tlb_entry(tlb, pud, addr); - if (vma_is_dax(vma)) { + if (vma_is_special_huge(vma)) { spin_unlock(ptl); /* No zero page support yet */ } else { @@ -2162,7 +2162,7 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, */ if (arch_needs_pgtable_deposit()) zap_deposited_table(mm, pmd); - if (vma_is_dax(vma)) + if (vma_is_special_huge(vma)) return; page = pmd_page(_pmd); if (!PageDirty(page) && pmd_dirty(_pmd)) -- 2.21.0 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel