unsigned long l4x_set_pmd(struct mm_struct *mm,
unsigned long addr,
pmd_t old, pmd_t pmdval)
{
/*
* Check if any invalidation is necessary
*
* Invalidation (flush) necessary if:
* old page was present
* new page is not present OR
* new page has another physical address OR
* new page has another protection OR
* new page has other access attributes
*/
/* old was present && new not -> flush */
int flush_rights = L4_FPAGE_RWX;
BUG_ON(!pmd_large(old));
if (pmd_present(pmdval)) {
/* new page is present,
* now we have to find out what has changed */
if (((pmd_val(old) ^ pmd_val(pmdval)) & PMD_PAGE_MASK & PHYSICAL_PAGE_MASK)
|| (pmd_young(old) && !pmd_young(pmdval))) {
/* physical page frame changed
* || access attribute changed -> flush */
/* flush is the default */
} else if ((pmd_write(old) && !pmd_write(pmdval))
|| (pmd_flags(old) & ~pmd_flags(pmdval)
& (_PAGE_DIRTY | _PAGE_SOFT_DIRTY))) {
/* Protection changed from r/w to ro
* or page now clean -> remap */
flush_rights = L4_FPAGE_W;
} else {
/* nothing changed, simply return */
return pmd_val(pmdval);
}
}
/* Ok, now actually flush or remap the page */
l4x_flush_page(mm, pmd_val(old) & PMD_PAGE_MASK & PHYSICAL_PAGE_MASK,
addr, PMD_SHIFT, flush_rights, _RET_IP_);
return pmd_val(pmdval);
}
static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
struct mm_walk *walk)
{
struct mem_size_stats *mss = walk->private;
struct vm_area_struct *vma = walk->vma;
struct page *page;
/* FOLL_DUMP will return -EFAULT on huge zero page */
page = follow_trans_huge_pmd(vma, addr, pmd, FOLL_DUMP);
if (IS_ERR_OR_NULL(page))
return;
mss->anonymous_thp += HPAGE_PMD_SIZE;
smaps_account(mss, page, HPAGE_PMD_SIZE,
pmd_young(*pmd), pmd_dirty(*pmd));
}
