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: Russell King <rmk+kernel@arm.linux.org.uk>
This commit is contained in:
Russell King 2009-12-18 16:21:35 +00:00
parent 24bc7347da
commit c26c20b823

View File

@ -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: