Commit 5cad465d authored by Matthew Wilcox's avatar Matthew Wilcox Committed by Linus Torvalds
Browse files

mm: add vmf_insert_pfn_pmd() 



Similar to vm_insert_pfn(), but for PMDs rather than PTEs.  The 'vmf_'
prefix instead of 'vm_' prefix is intended to indicate that it returns a
VMF_ value rather than an errno (which would only have to be converted
into a VMF_ value anyway).

Signed-off-by: default avatarMatthew Wilcox <willy@linux.intel.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent fc437044

include/linux/huge_mm.h

+2 −0
Original line number Diff line number Diff line
@@ -33,6 +33,8 @@ extern int move_huge_pmd(struct vm_area_struct *vma, 
extern int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd,

			unsigned long addr, pgprot_t newprot,

			int prot_numa);

int vmf_insert_pfn_pmd(struct vm_area_struct *, unsigned long addr, pmd_t *,

			unsigned long pfn, bool write);



enum transparent_hugepage_flag {

	TRANSPARENT_HUGEPAGE_FLAG,

mm/huge_memory.c

+43 −0
Original line number Diff line number Diff line
@@ -869,6 +869,49 @@ int do_huge_pmd_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma, 
					    flags);

}



static int insert_pfn_pmd(struct vm_area_struct *vma, unsigned long addr,

		pmd_t *pmd, unsigned long pfn, pgprot_t prot, bool write)

{

	struct mm_struct *mm = vma->vm_mm;

	pmd_t entry;

	spinlock_t *ptl;



	ptl = pmd_lock(mm, pmd);

	if (pmd_none(*pmd)) {

		entry = pmd_mkhuge(pfn_pmd(pfn, prot));

		if (write) {

			entry = pmd_mkyoung(pmd_mkdirty(entry));

			entry = maybe_pmd_mkwrite(entry, vma);

		}

		set_pmd_at(mm, addr, pmd, entry);

		update_mmu_cache_pmd(vma, addr, pmd);

	}

	spin_unlock(ptl);

	return VM_FAULT_NOPAGE;

}



int vmf_insert_pfn_pmd(struct vm_area_struct *vma, unsigned long addr,

			pmd_t *pmd, unsigned long pfn, bool write)

{

	pgprot_t pgprot = vma->vm_page_prot;

	/*

	 * If we had pmd_special, we could avoid all these restrictions,

	 * but we need to be consistent with PTEs and architectures that

	 * can't support a 'special' bit.

	 */

	BUG_ON(!(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)));

	BUG_ON((vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)) ==

						(VM_PFNMAP|VM_MIXEDMAP));

	BUG_ON((vma->vm_flags & VM_PFNMAP) && is_cow_mapping(vma->vm_flags));

	BUG_ON((vma->vm_flags & VM_MIXEDMAP) && pfn_valid(pfn));



	if (addr < vma->vm_start || addr >= vma->vm_end)

		return VM_FAULT_SIGBUS;

	if (track_pfn_insert(vma, &pgprot, pfn))

		return VM_FAULT_SIGBUS;

	return insert_pfn_pmd(vma, addr, pmd, pfn, pgprot, write);

}



int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,

		  pmd_t *dst_pmd, pmd_t *src_pmd, unsigned long addr,

		  struct vm_area_struct *vma)

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