/*
* The performance critical leaf functions are made noinline otherwise gcc
* inlines everything into a single function which results in too much
* register pressure.
*/
static noinline int gup_pte_range(pmd_t pmd, unsigned long addr,
unsigned long end, int write, struct page **pages, int *nr)
{
unsigned long mask, result;
pte_t *ptep;
result = _PAGE_PRESENT|_PAGE_USER;
if (write)
result |= _PAGE_RW;
mask = result | _PAGE_SPECIAL;
ptep = pte_offset_kernel(&pmd, addr);
do {
pte_t pte = *ptep;
struct page *page;
if ((pte_val(pte) & mask) != result)
return 0;
VM_BUG_ON(!pfn_valid(pte_pfn(pte)));
page = pte_page(pte);
if (!page_cache_get_speculative(page))
return 0;
if (unlikely(pte_val(pte) != pte_val(*ptep))) {
put_page(page);
return 0;
}
pages[*nr] = page;
(*nr)++;
} while (ptep++, addr += PAGE_SIZE, addr != end);
return 1;
}
/*
* The performance critical leaf functions are made noinline otherwise gcc
* inlines everything into a single function which results in too much
* register pressure.
*/
static noinline int gup_pte_range(pmd_t pmd, unsigned long addr,
unsigned long end, int write, struct page **pages, int *nr)
{
unsigned long mask, result;
pte_t *ptep;
if (tlb_type == hypervisor) {
result = _PAGE_PRESENT_4V|_PAGE_P_4V;
if (write)
result |= _PAGE_WRITE_4V;
} else {
result = _PAGE_PRESENT_4U|_PAGE_P_4U;
if (write)
result |= _PAGE_WRITE_4U;
}
mask = result | _PAGE_SPECIAL;
ptep = pte_offset_kernel(&pmd, addr);
do {
struct page *page, *head;
pte_t pte = *ptep;
if ((pte_val(pte) & mask) != result)
return 0;
VM_BUG_ON(!pfn_valid(pte_pfn(pte)));
/* The hugepage case is simplified on sparc64 because
* we encode the sub-page pfn offsets into the
* hugepage PTEs. We could optimize this in the future
* use page_cache_add_speculative() for the hugepage case.
*/
page = pte_page(pte);
head = compound_head(page);
if (!page_cache_get_speculative(head))
return 0;
if (unlikely(pte_val(pte) != pte_val(*ptep))) {
put_page(head);
return 0;
}
pages[*nr] = page;
(*nr)++;
} while (ptep++, addr += PAGE_SIZE, addr != end);
return 1;
}
static noinline int gup_pte_range(pmd_t pmd, unsigned long addr,
unsigned long end, int write, struct page **pages, int *nr)
{
unsigned long mask, result;
pte_t *ptep;
if (tlb_type == hypervisor) {
result = _PAGE_PRESENT_4V|_PAGE_P_4V;
if (write)
result |= _PAGE_WRITE_4V;
} else {
result = _PAGE_PRESENT_4U|_PAGE_P_4U;
if (write)
result |= _PAGE_WRITE_4U;
}
mask = result | _PAGE_SPECIAL;
ptep = pte_offset_kernel(&pmd, addr);
do {
struct page *page, *head;
pte_t pte = *ptep;
if ((pte_val(pte) & mask) != result)
return 0;
VM_BUG_ON(!pfn_valid(pte_pfn(pte)));
page = pte_page(pte);
head = compound_head(page);
if (!page_cache_get_speculative(head))
return 0;
if (unlikely(pte_val(pte) != pte_val(*ptep))) {
put_page(head);
return 0;
}
if (head != page)
get_huge_page_tail(page);
pages[*nr] = page;
(*nr)++;
} while (ptep++, addr += PAGE_SIZE, addr != end);
return 1;
}
