blob: 7c29d38e6b99c68c5ac746eb3d3a3fe1da8394a5 [file] [log] [blame]
/*
* SPARC64 Huge TLB page support.
*
* Copyright (C) 2002, 2003, 2006 David S. Miller (davem@davemloft.net)
*/
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/sched/mm.h>
#include <linux/hugetlb.h>
#include <linux/pagemap.h>
#include <linux/sysctl.h>
#include <asm/mman.h>
#include <asm/pgalloc.h>
#include <asm/pgtable.h>
#include <asm/tlb.h>
#include <asm/tlbflush.h>
#include <asm/cacheflush.h>
#include <asm/mmu_context.h>
/* Slightly simplified from the non-hugepage variant because by
* definition we don't have to worry about any page coloring stuff
*/
static unsigned long hugetlb_get_unmapped_area_bottomup(struct file *filp,
unsigned long addr,
unsigned long len,
unsigned long pgoff,
unsigned long flags)
{
struct hstate *h = hstate_file(filp);
unsigned long task_size = TASK_SIZE;
struct vm_unmapped_area_info info;
if (test_thread_flag(TIF_32BIT))
task_size = STACK_TOP32;
info.flags = 0;
info.length = len;
info.low_limit = TASK_UNMAPPED_BASE;
info.high_limit = min(task_size, VA_EXCLUDE_START);
info.align_mask = PAGE_MASK & ~huge_page_mask(h);
info.align_offset = 0;
addr = vm_unmapped_area(&info);
if ((addr & ~PAGE_MASK) && task_size > VA_EXCLUDE_END) {
VM_BUG_ON(addr != -ENOMEM);
info.low_limit = VA_EXCLUDE_END;
info.high_limit = task_size;
addr = vm_unmapped_area(&info);
}
return addr;
}
static unsigned long
hugetlb_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
const unsigned long len,
const unsigned long pgoff,
const unsigned long flags)
{
struct hstate *h = hstate_file(filp);
struct mm_struct *mm = current->mm;
unsigned long addr = addr0;
struct vm_unmapped_area_info info;
/* This should only ever run for 32-bit processes. */
BUG_ON(!test_thread_flag(TIF_32BIT));
info.flags = VM_UNMAPPED_AREA_TOPDOWN;
info.length = len;
info.low_limit = PAGE_SIZE;
info.high_limit = mm->mmap_base;
info.align_mask = PAGE_MASK & ~huge_page_mask(h);
info.align_offset = 0;
addr = vm_unmapped_area(&info);
/*
* A failed mmap() very likely causes application failure,
* so fall back to the bottom-up function here. This scenario
* can happen with large stack limits and large mmap()
* allocations.
*/
if (addr & ~PAGE_MASK) {
VM_BUG_ON(addr != -ENOMEM);
info.flags = 0;
info.low_limit = TASK_UNMAPPED_BASE;
info.high_limit = STACK_TOP32;
addr = vm_unmapped_area(&info);
}
return addr;
}
unsigned long
hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
unsigned long len, unsigned long pgoff, unsigned long flags)
{
struct hstate *h = hstate_file(file);
struct mm_struct *mm = current->mm;
struct vm_area_struct *vma;
unsigned long task_size = TASK_SIZE;
if (test_thread_flag(TIF_32BIT))
task_size = STACK_TOP32;
if (len & ~huge_page_mask(h))
return -EINVAL;
if (len > task_size)
return -ENOMEM;
if (flags & MAP_FIXED) {
if (prepare_hugepage_range(file, addr, len))
return -EINVAL;
return addr;
}
if (addr) {
addr = ALIGN(addr, huge_page_size(h));
vma = find_vma(mm, addr);
if (task_size - len >= addr &&
(!vma || addr + len <= vma->vm_start))
return addr;
}
if (mm->get_unmapped_area == arch_get_unmapped_area)
return hugetlb_get_unmapped_area_bottomup(file, addr, len,
pgoff, flags);
else
return hugetlb_get_unmapped_area_topdown(file, addr, len,
pgoff, flags);
}
static pte_t sun4u_hugepage_shift_to_tte(pte_t entry, unsigned int shift)
{
return entry;
}
static pte_t sun4v_hugepage_shift_to_tte(pte_t entry, unsigned int shift)
{
unsigned long hugepage_size = _PAGE_SZ4MB_4V;
pte_val(entry) = pte_val(entry) & ~_PAGE_SZALL_4V;
switch (shift) {
case HPAGE_2GB_SHIFT:
hugepage_size = _PAGE_SZ2GB_4V;
pte_val(entry) |= _PAGE_PMD_HUGE;
break;
case HPAGE_256MB_SHIFT:
hugepage_size = _PAGE_SZ256MB_4V;
pte_val(entry) |= _PAGE_PMD_HUGE;
break;
case HPAGE_SHIFT:
pte_val(entry) |= _PAGE_PMD_HUGE;
break;
case HPAGE_64K_SHIFT:
hugepage_size = _PAGE_SZ64K_4V;
break;
default:
WARN_ONCE(1, "unsupported hugepage shift=%u\n", shift);
}
pte_val(entry) = pte_val(entry) | hugepage_size;
return entry;
}
static pte_t hugepage_shift_to_tte(pte_t entry, unsigned int shift)
{
if (tlb_type == hypervisor)
return sun4v_hugepage_shift_to_tte(entry, shift);
else
return sun4u_hugepage_shift_to_tte(entry, shift);
}
pte_t arch_make_huge_pte(pte_t entry, struct vm_area_struct *vma,
struct page *page, int writeable)
{
unsigned int shift = huge_page_shift(hstate_vma(vma));
return hugepage_shift_to_tte(entry, shift);
}
static unsigned int sun4v_huge_tte_to_shift(pte_t entry)
{
unsigned long tte_szbits = pte_val(entry) & _PAGE_SZALL_4V;
unsigned int shift;
switch (tte_szbits) {
case _PAGE_SZ2GB_4V:
shift = HPAGE_2GB_SHIFT;
break;
case _PAGE_SZ256MB_4V:
shift = HPAGE_256MB_SHIFT;
break;
case _PAGE_SZ4MB_4V:
shift = REAL_HPAGE_SHIFT;
break;
case _PAGE_SZ64K_4V:
shift = HPAGE_64K_SHIFT;
break;
default:
shift = PAGE_SHIFT;
break;
}
return shift;
}
static unsigned int sun4u_huge_tte_to_shift(pte_t entry)
{
unsigned long tte_szbits = pte_val(entry) & _PAGE_SZALL_4U;
unsigned int shift;
switch (tte_szbits) {
case _PAGE_SZ256MB_4U:
shift = HPAGE_256MB_SHIFT;
break;
case _PAGE_SZ4MB_4U:
shift = REAL_HPAGE_SHIFT;
break;
case _PAGE_SZ64K_4U:
shift = HPAGE_64K_SHIFT;
break;
default:
shift = PAGE_SHIFT;
break;
}
return shift;
}
static unsigned int huge_tte_to_shift(pte_t entry)
{
unsigned long shift;
if (tlb_type == hypervisor)
shift = sun4v_huge_tte_to_shift(entry);
else
shift = sun4u_huge_tte_to_shift(entry);
if (shift == PAGE_SHIFT)
WARN_ONCE(1, "tto_to_shift: invalid hugepage tte=0x%lx\n",
pte_val(entry));
return shift;
}
static unsigned long huge_tte_to_size(pte_t pte)
{
unsigned long size = 1UL << huge_tte_to_shift(pte);
if (size == REAL_HPAGE_SIZE)
size = HPAGE_SIZE;
return size;
}
pte_t *huge_pte_alloc(struct mm_struct *mm,
unsigned long addr, unsigned long sz)
{
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
pte_t *pte = NULL;
pgd = pgd_offset(mm, addr);
pud = pud_alloc(mm, pgd, addr);
if (pud) {
pmd = pmd_alloc(mm, pud, addr);
if (!pmd)
return NULL;
if (sz >= PMD_SIZE)
pte = (pte_t *)pmd;
else
pte = pte_alloc_map(mm, pmd, addr);
}
return pte;
}
pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
{
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
pte_t *pte = NULL;
pgd = pgd_offset(mm, addr);
if (!pgd_none(*pgd)) {
pud = pud_offset(pgd, addr);
if (!pud_none(*pud)) {
pmd = pmd_offset(pud, addr);
if (!pmd_none(*pmd)) {
if (is_hugetlb_pmd(*pmd))
pte = (pte_t *)pmd;
else
pte = pte_offset_map(pmd, addr);
}
}
}
return pte;
}
void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, pte_t entry)
{
unsigned int i, nptes, orig_shift, shift;
unsigned long size;
pte_t orig;
size = huge_tte_to_size(entry);
shift = size >= HPAGE_SIZE ? PMD_SHIFT : PAGE_SHIFT;
nptes = size >> shift;
if (!pte_present(*ptep) && pte_present(entry))
mm->context.hugetlb_pte_count += nptes;
addr &= ~(size - 1);
orig = *ptep;
orig_shift = pte_none(orig) ? PAGE_SHIFT : huge_tte_to_shift(orig);
for (i = 0; i < nptes; i++)
ptep[i] = __pte(pte_val(entry) + (i << shift));
maybe_tlb_batch_add(mm, addr, ptep, orig, 0, orig_shift);
/* An HPAGE_SIZE'ed page is composed of two REAL_HPAGE_SIZE'ed pages */
if (size == HPAGE_SIZE)
maybe_tlb_batch_add(mm, addr + REAL_HPAGE_SIZE, ptep, orig, 0,
orig_shift);
}
pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
pte_t *ptep)
{
unsigned int i, nptes, hugepage_shift;
unsigned long size;
pte_t entry;
entry = *ptep;
size = huge_tte_to_size(entry);
if (size >= HPAGE_SIZE)
nptes = size >> PMD_SHIFT;
else
nptes = size >> PAGE_SHIFT;
hugepage_shift = pte_none(entry) ? PAGE_SHIFT :
huge_tte_to_shift(entry);
if (pte_present(entry))
mm->context.hugetlb_pte_count -= nptes;
addr &= ~(size - 1);
for (i = 0; i < nptes; i++)
ptep[i] = __pte(0UL);
maybe_tlb_batch_add(mm, addr, ptep, entry, 0, hugepage_shift);
/* An HPAGE_SIZE'ed page is composed of two REAL_HPAGE_SIZE'ed pages */
if (size == HPAGE_SIZE)
maybe_tlb_batch_add(mm, addr + REAL_HPAGE_SIZE, ptep, entry, 0,
hugepage_shift);
return entry;
}
int pmd_huge(pmd_t pmd)
{
return !pmd_none(pmd) &&
(pmd_val(pmd) & (_PAGE_VALID|_PAGE_PMD_HUGE)) != _PAGE_VALID;
}
int pud_huge(pud_t pud)
{
return 0;
}
static void hugetlb_free_pte_range(struct mmu_gather *tlb, pmd_t *pmd,
unsigned long addr)
{
pgtable_t token = pmd_pgtable(*pmd);
pmd_clear(pmd);
pte_free_tlb(tlb, token, addr);
atomic_long_dec(&tlb->mm->nr_ptes);
}
static void hugetlb_free_pmd_range(struct mmu_gather *tlb, pud_t *pud,
unsigned long addr, unsigned long end,
unsigned long floor, unsigned long ceiling)
{
pmd_t *pmd;
unsigned long next;
unsigned long start;
start = addr;
pmd = pmd_offset(pud, addr);
do {
next = pmd_addr_end(addr, end);
if (pmd_none(*pmd))
continue;
if (is_hugetlb_pmd(*pmd))
pmd_clear(pmd);
else
hugetlb_free_pte_range(tlb, pmd, addr);
} while (pmd++, addr = next, addr != end);
start &= PUD_MASK;
if (start < floor)
return;
if (ceiling) {
ceiling &= PUD_MASK;
if (!ceiling)
return;
}
if (end - 1 > ceiling - 1)
return;
pmd = pmd_offset(pud, start);
pud_clear(pud);
pmd_free_tlb(tlb, pmd, start);
mm_dec_nr_pmds(tlb->mm);
}
static void hugetlb_free_pud_range(struct mmu_gather *tlb, pgd_t *pgd,
unsigned long addr, unsigned long end,
unsigned long floor, unsigned long ceiling)
{
pud_t *pud;
unsigned long next;
unsigned long start;
start = addr;
pud = pud_offset(pgd, addr);
do {
next = pud_addr_end(addr, end);
if (pud_none_or_clear_bad(pud))
continue;
hugetlb_free_pmd_range(tlb, pud, addr, next, floor,
ceiling);
} while (pud++, addr = next, addr != end);
start &= PGDIR_MASK;
if (start < floor)
return;
if (ceiling) {
ceiling &= PGDIR_MASK;
if (!ceiling)
return;
}
if (end - 1 > ceiling - 1)
return;
pud = pud_offset(pgd, start);
pgd_clear(pgd);
pud_free_tlb(tlb, pud, start);
}
void hugetlb_free_pgd_range(struct mmu_gather *tlb,
unsigned long addr, unsigned long end,
unsigned long floor, unsigned long ceiling)
{
pgd_t *pgd;
unsigned long next;
addr &= PMD_MASK;
if (addr < floor) {
addr += PMD_SIZE;
if (!addr)
return;
}
if (ceiling) {
ceiling &= PMD_MASK;
if (!ceiling)
return;
}
if (end - 1 > ceiling - 1)
end -= PMD_SIZE;
if (addr > end - 1)
return;
pgd = pgd_offset(tlb->mm, addr);
do {
next = pgd_addr_end(addr, end);
if (pgd_none_or_clear_bad(pgd))
continue;
hugetlb_free_pud_range(tlb, pgd, addr, next, floor, ceiling);
} while (pgd++, addr = next, addr != end);
}