Commit c26c20b8 authored by Russell King's avatar Russell King
Browse files

ARM: make_coherent: split adjust_pte() in two 



adjust_pte() walks the page tables, and do_adjust_pte() does the
page table manipulation.

Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent 24bc7347

arch/arm/mm/fault-armv.c

+32 −20
Original line number Diff line number Diff line
@@ -36,28 +36,12 @@ static unsigned long shared_pte_mask = L_PTE_MT_BUFFERABLE; 
 * Therefore those configurations which might call adjust_pte (those

 * without CONFIG_CPU_CACHE_VIPT) cannot support split page_table_lock.

 */

static int adjust_pte(struct vm_area_struct *vma, unsigned long address)

static int do_adjust_pte(struct vm_area_struct *vma, unsigned long address,

	pte_t *ptep)

{

	pgd_t *pgd;

	pmd_t *pmd;

	pte_t *pte, entry;

	pte_t entry = *ptep;

	int ret;



	pgd = pgd_offset(vma->vm_mm, address);

	if (pgd_none(*pgd))

		goto no_pgd;

	if (pgd_bad(*pgd))

		goto bad_pgd;



	pmd = pmd_offset(pgd, address);

	if (pmd_none(*pmd))

		goto no_pmd;

	if (pmd_bad(*pmd))

		goto bad_pmd;



	pte = pte_offset_map(pmd, address);

	entry = *pte;



	/*

	 * If this page is present, it's actually being shared.

	 */
@@ -74,10 +58,38 @@ static int adjust_pte(struct vm_area_struct *vma, unsigned long address) 
				  (pfn << PAGE_SHIFT) + PAGE_SIZE);

		pte_val(entry) &= ~L_PTE_MT_MASK;

		pte_val(entry) |= shared_pte_mask;

		set_pte_at(vma->vm_mm, address, pte, entry);

		set_pte_at(vma->vm_mm, address, ptep, entry);

		flush_tlb_page(vma, address);

	}



	return ret;

}



static int adjust_pte(struct vm_area_struct *vma, unsigned long address)

{

	pgd_t *pgd;

	pmd_t *pmd;

	pte_t *pte;

	int ret;



	pgd = pgd_offset(vma->vm_mm, address);

	if (pgd_none(*pgd))

		goto no_pgd;

	if (pgd_bad(*pgd))

		goto bad_pgd;



	pmd = pmd_offset(pgd, address);

	if (pmd_none(*pmd))

		goto no_pmd;

	if (pmd_bad(*pmd))

		goto bad_pmd;



	pte = pte_offset_map(pmd, address);



	ret = do_adjust_pte(vma, address, pte);



	pte_unmap(pte);



	return ret;



bad_pgd: