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/*
* 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/hugetlb.h>
#include <linux/pagemap.h>
#include <linux/sysctl.h>
#include <asm/mman.h>
#include <asm/pgalloc.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)
{
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 & ~HPAGE_MASK;
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 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 & ~HPAGE_MASK;
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 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 & ~HPAGE_MASK)
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, HPAGE_SIZE);
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);
}
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;
/* We must align the address, because our caller will run
* set_huge_pte_at() on whatever we return, which writes out
* all of the sub-ptes for the hugepage range. So we have
* to give it the first such sub-pte.
*/
addr &= HPAGE_MASK;
pgd = pgd_offset(mm, addr);
pud = pud_alloc(mm, pgd, addr);
if (pud) {
pmd = pmd_alloc(mm, pud, addr);
if (pmd)
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;
addr &= HPAGE_MASK;
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))
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)
{
int i;
pte_t orig[2];
unsigned long nptes;
if (!pte_present(*ptep) && pte_present(entry))
mm->context.hugetlb_pte_count++;
addr &= HPAGE_MASK;
nptes = 1 << HUGETLB_PAGE_ORDER;
orig[0] = *ptep;
orig[1] = *(ptep + nptes / 2);
for (i = 0; i < nptes; i++) {
*ptep = entry;
ptep++;
addr += PAGE_SIZE;
pte_val(entry) += PAGE_SIZE;
}
/* Issue TLB flush at REAL_HPAGE_SIZE boundaries */
addr -= REAL_HPAGE_SIZE;
ptep -= nptes / 2;
maybe_tlb_batch_add(mm, addr, ptep, orig[1], 0);
addr -= REAL_HPAGE_SIZE;
ptep -= nptes / 2;
maybe_tlb_batch_add(mm, addr, ptep, orig[0], 0);
}
pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
pte_t *ptep)
{
pte_t entry;
int i;
unsigned long nptes;
entry = *ptep;
if (pte_present(entry))
mm->context.hugetlb_pte_count--;
addr &= HPAGE_MASK;
nptes = 1 << HUGETLB_PAGE_ORDER;
for (i = 0; i < nptes; i++) {
*ptep = __pte(0UL);
addr += PAGE_SIZE;
ptep++;
}
/* Issue TLB flush at REAL_HPAGE_SIZE boundaries */
addr -= REAL_HPAGE_SIZE;
ptep -= nptes / 2;
maybe_tlb_batch_add(mm, addr, ptep, entry, 0);
addr -= REAL_HPAGE_SIZE;
ptep -= nptes / 2;
maybe_tlb_batch_add(mm, addr, ptep, entry, 0);
return entry;
}
int pmd_huge(pmd_t pmd)
{
return 0;
}
int pud_huge(pud_t pud)
{
return 0;
}
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