#include <asm/tlb.h>
#include <asm/tlbflush.h>
-static pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr)
+pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr)
{
pgd_t *pgd;
pud_t *pud;
return (pte_t *) pmd;
}
-static pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
+pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
{
pgd_t *pgd;
pud_t *pud;
return (pte_t *) pmd;
}
-static void set_huge_pte(struct mm_struct *mm, struct vm_area_struct *vma, struct page *page, pte_t * page_table, int write_access)
-{
- pte_t entry;
-
- add_mm_counter(mm, rss, HPAGE_SIZE / PAGE_SIZE);
- if (write_access) {
- entry =
- pte_mkwrite(pte_mkdirty(mk_pte(page, vma->vm_page_prot)));
- } else
- entry = pte_wrprotect(mk_pte(page, vma->vm_page_prot));
- entry = pte_mkyoung(entry);
- mk_pte_huge(entry);
- set_pte(page_table, entry);
-}
-
/*
* This function checks for proper alignment of input addr and len parameters.
*/
return 0;
}
-int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src,
- struct vm_area_struct *vma)
-{
- pte_t *src_pte, *dst_pte, entry;
- struct page *ptepage;
- unsigned long addr = vma->vm_start;
- unsigned long end = vma->vm_end;
-
- while (addr < end) {
- dst_pte = huge_pte_alloc(dst, addr);
- if (!dst_pte)
- goto nomem;
- src_pte = huge_pte_offset(src, addr);
- entry = *src_pte;
- ptepage = pte_page(entry);
- get_page(ptepage);
- set_pte(dst_pte, entry);
- add_mm_counter(dst, rss, HPAGE_SIZE / PAGE_SIZE);
- addr += HPAGE_SIZE;
- }
- return 0;
-
-nomem:
- return -ENOMEM;
-}
-
-int
-follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma,
- struct page **pages, struct vm_area_struct **vmas,
- unsigned long *position, int *length, int i)
-{
- unsigned long vpfn, vaddr = *position;
- int remainder = *length;
-
- WARN_ON(!is_vm_hugetlb_page(vma));
-
- vpfn = vaddr/PAGE_SIZE;
- while (vaddr < vma->vm_end && remainder) {
-
- if (pages) {
- pte_t *pte;
- struct page *page;
-
- pte = huge_pte_offset(mm, vaddr);
-
- /* hugetlb should be locked, and hence, prefaulted */
- WARN_ON(!pte || pte_none(*pte));
-
- page = &pte_page(*pte)[vpfn % (HPAGE_SIZE/PAGE_SIZE)];
-
- WARN_ON(!PageCompound(page));
-
- get_page(page);
- pages[i] = page;
- }
-
- if (vmas)
- vmas[i] = vma;
-
- vaddr += PAGE_SIZE;
- ++vpfn;
- --remainder;
- ++i;
- }
-
- *length = remainder;
- *position = vaddr;
-
- return i;
-}
-
#if 0 /* This is just for testing */
struct page *
follow_huge_addr(struct mm_struct *mm, unsigned long address, int write)
}
#endif
-void unmap_hugepage_range(struct vm_area_struct *vma,
- unsigned long start, unsigned long end)
+void hugetlb_clean_stale_pgtable(pte_t *pte)
{
- struct mm_struct *mm = vma->vm_mm;
- unsigned long address;
- pte_t pte, *ptep;
+ pmd_t *pmd = (pmd_t *) pte;
struct page *page;
- BUG_ON(start & (HPAGE_SIZE - 1));
- BUG_ON(end & (HPAGE_SIZE - 1));
-
- for (address = start; address < end; address += HPAGE_SIZE) {
- ptep = huge_pte_offset(mm, address);
- if (!ptep)
- continue;
- pte = ptep_get_and_clear(mm, address, ptep);
- if (pte_none(pte))
- continue;
- page = pte_page(pte);
- put_page(page);
- }
- add_mm_counter(mm ,rss, -((end - start) >> PAGE_SHIFT));
- flush_tlb_range(vma, start, end);
-}
-
-int hugetlb_prefault(struct address_space *mapping, struct vm_area_struct *vma)
-{
- struct mm_struct *mm = current->mm;
- unsigned long addr;
- int ret = 0;
-
- BUG_ON(vma->vm_start & ~HPAGE_MASK);
- BUG_ON(vma->vm_end & ~HPAGE_MASK);
-
- spin_lock(&mm->page_table_lock);
- for (addr = vma->vm_start; addr < vma->vm_end; addr += HPAGE_SIZE) {
- unsigned long idx;
- pte_t *pte = huge_pte_alloc(mm, addr);
- struct page *page;
-
- if (!pte) {
- ret = -ENOMEM;
- goto out;
- }
-
- if (!pte_none(*pte))
- continue;
-
- idx = ((addr - vma->vm_start) >> HPAGE_SHIFT)
- + (vma->vm_pgoff >> (HPAGE_SHIFT - PAGE_SHIFT));
- page = find_get_page(mapping, idx);
- if (!page) {
- /* charge the fs quota first */
- if (hugetlb_get_quota(mapping)) {
- ret = -ENOMEM;
- goto out;
- }
- page = alloc_huge_page();
- if (!page) {
- hugetlb_put_quota(mapping);
- ret = -ENOMEM;
- goto out;
- }
- ret = add_to_page_cache(page, mapping, idx, GFP_ATOMIC);
- if (! ret) {
- unlock_page(page);
- } else {
- hugetlb_put_quota(mapping);
- free_huge_page(page);
- goto out;
- }
- }
- set_huge_pte(mm, vma, page, pte, vma->vm_flags & VM_WRITE);
- }
-out:
- spin_unlock(&mm->page_table_lock);
- return ret;
+ page = pmd_page(*pmd);
+ pmd_clear(pmd);
+ dec_page_state(nr_page_table_pages);
+ page_cache_release(page);
}
/* x86_64 also uses this file */
unsigned int hpage_shift=HPAGE_SHIFT_DEFAULT;
-static pte_t *
+pte_t *
huge_pte_alloc (struct mm_struct *mm, unsigned long addr)
{
unsigned long taddr = htlbpage_to_page(addr);
return pte;
}
-static pte_t *
+pte_t *
huge_pte_offset (struct mm_struct *mm, unsigned long addr)
{
unsigned long taddr = htlbpage_to_page(addr);
#define mk_pte_huge(entry) { pte_val(entry) |= _PAGE_P; }
-static void
-set_huge_pte (struct mm_struct *mm, struct vm_area_struct *vma,
- struct page *page, pte_t * page_table, int write_access)
-{
- pte_t entry;
-
- add_mm_counter(mm, rss, HPAGE_SIZE / PAGE_SIZE);
- if (write_access) {
- entry =
- pte_mkwrite(pte_mkdirty(mk_pte(page, vma->vm_page_prot)));
- } else
- entry = pte_wrprotect(mk_pte(page, vma->vm_page_prot));
- entry = pte_mkyoung(entry);
- mk_pte_huge(entry);
- set_pte(page_table, entry);
- return;
-}
/*
* This function checks for proper alignment of input addr and len parameters.
*/
return 0;
}
-int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src,
- struct vm_area_struct *vma)
-{
- pte_t *src_pte, *dst_pte, entry;
- struct page *ptepage;
- unsigned long addr = vma->vm_start;
- unsigned long end = vma->vm_end;
-
- while (addr < end) {
- dst_pte = huge_pte_alloc(dst, addr);
- if (!dst_pte)
- goto nomem;
- src_pte = huge_pte_offset(src, addr);
- entry = *src_pte;
- ptepage = pte_page(entry);
- get_page(ptepage);
- set_pte(dst_pte, entry);
- add_mm_counter(dst, rss, HPAGE_SIZE / PAGE_SIZE);
- addr += HPAGE_SIZE;
- }
- return 0;
-nomem:
- return -ENOMEM;
-}
-
-int
-follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma,
- struct page **pages, struct vm_area_struct **vmas,
- unsigned long *st, int *length, int i)
-{
- pte_t *ptep, pte;
- unsigned long start = *st;
- unsigned long pstart;
- int len = *length;
- struct page *page;
-
- do {
- pstart = start & HPAGE_MASK;
- ptep = huge_pte_offset(mm, start);
- pte = *ptep;
-
-back1:
- page = pte_page(pte);
- if (pages) {
- page += ((start & ~HPAGE_MASK) >> PAGE_SHIFT);
- get_page(page);
- pages[i] = page;
- }
- if (vmas)
- vmas[i] = vma;
- i++;
- len--;
- start += PAGE_SIZE;
- if (((start & HPAGE_MASK) == pstart) && len &&
- (start < vma->vm_end))
- goto back1;
- } while (len && start < vma->vm_end);
- *length = len;
- *st = start;
- return i;
-}
-
struct page *follow_huge_addr(struct mm_struct *mm, unsigned long addr, int write)
{
struct page *page;
free_pgd_range(tlb, addr, end, floor, ceiling);
}
-void unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start, unsigned long end)
-{
- struct mm_struct *mm = vma->vm_mm;
- unsigned long address;
- pte_t *pte;
- struct page *page;
-
- BUG_ON(start & (HPAGE_SIZE - 1));
- BUG_ON(end & (HPAGE_SIZE - 1));
-
- for (address = start; address < end; address += HPAGE_SIZE) {
- pte = huge_pte_offset(mm, address);
- if (pte_none(*pte))
- continue;
- page = pte_page(*pte);
- put_page(page);
- pte_clear(mm, address, pte);
- }
- add_mm_counter(mm, rss, - ((end - start) >> PAGE_SHIFT));
- flush_tlb_range(vma, start, end);
-}
-
-int hugetlb_prefault(struct address_space *mapping, struct vm_area_struct *vma)
-{
- struct mm_struct *mm = current->mm;
- unsigned long addr;
- int ret = 0;
-
- BUG_ON(vma->vm_start & ~HPAGE_MASK);
- BUG_ON(vma->vm_end & ~HPAGE_MASK);
-
- spin_lock(&mm->page_table_lock);
- for (addr = vma->vm_start; addr < vma->vm_end; addr += HPAGE_SIZE) {
- unsigned long idx;
- pte_t *pte = huge_pte_alloc(mm, addr);
- struct page *page;
-
- if (!pte) {
- ret = -ENOMEM;
- goto out;
- }
- if (!pte_none(*pte))
- continue;
-
- idx = ((addr - vma->vm_start) >> HPAGE_SHIFT)
- + (vma->vm_pgoff >> (HPAGE_SHIFT - PAGE_SHIFT));
- page = find_get_page(mapping, idx);
- if (!page) {
- /* charge the fs quota first */
- if (hugetlb_get_quota(mapping)) {
- ret = -ENOMEM;
- goto out;
- }
- page = alloc_huge_page();
- if (!page) {
- hugetlb_put_quota(mapping);
- ret = -ENOMEM;
- goto out;
- }
- ret = add_to_page_cache(page, mapping, idx, GFP_ATOMIC);
- if (! ret) {
- unlock_page(page);
- } else {
- hugetlb_put_quota(mapping);
- page_cache_release(page);
- goto out;
- }
- }
- set_huge_pte(mm, vma, page, pte, vma->vm_flags & VM_WRITE);
- }
-out:
- spin_unlock(&mm->page_table_lock);
- return ret;
-}
-
unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr, unsigned long len,
unsigned long pgoff, unsigned long flags)
{
return hugepte_offset(dir, addr);
}
-static pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
+pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
{
pud_t *pud;
return hugepte_offset(pud, addr);
}
-static pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr)
+pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr)
{
pud_t *pud;
return hugepte_alloc(mm, pud, addr);
}
-static void set_huge_pte(struct mm_struct *mm, struct vm_area_struct *vma,
- unsigned long addr, struct page *page,
- pte_t *ptep, int write_access)
-{
- pte_t entry;
-
- add_mm_counter(mm, rss, HPAGE_SIZE / PAGE_SIZE);
- if (write_access) {
- entry =
- pte_mkwrite(pte_mkdirty(mk_pte(page, vma->vm_page_prot)));
- } else {
- entry = pte_wrprotect(mk_pte(page, vma->vm_page_prot));
- }
- entry = pte_mkyoung(entry);
- entry = pte_mkhuge(entry);
-
- set_pte_at(mm, addr, ptep, entry);
-}
-
/*
* This function checks for proper alignment of input addr and len parameters.
*/
return -EINVAL;
}
-int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src,
- struct vm_area_struct *vma)
-{
- pte_t *src_pte, *dst_pte, entry;
- struct page *ptepage;
- unsigned long addr = vma->vm_start;
- unsigned long end = vma->vm_end;
- int err = -ENOMEM;
-
- while (addr < end) {
- dst_pte = huge_pte_alloc(dst, addr);
- if (!dst_pte)
- goto out;
-
- src_pte = huge_pte_offset(src, addr);
- entry = *src_pte;
-
- ptepage = pte_page(entry);
- get_page(ptepage);
- add_mm_counter(dst, rss, HPAGE_SIZE / PAGE_SIZE);
- set_pte_at(dst, addr, dst_pte, entry);
-
- addr += HPAGE_SIZE;
- }
-
- err = 0;
- out:
- return err;
-}
-
-int
-follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma,
- struct page **pages, struct vm_area_struct **vmas,
- unsigned long *position, int *length, int i)
-{
- unsigned long vpfn, vaddr = *position;
- int remainder = *length;
-
- WARN_ON(!is_vm_hugetlb_page(vma));
-
- vpfn = vaddr/PAGE_SIZE;
- while (vaddr < vma->vm_end && remainder) {
- if (pages) {
- pte_t *pte;
- struct page *page;
-
- pte = huge_pte_offset(mm, vaddr);
-
- /* hugetlb should be locked, and hence, prefaulted */
- WARN_ON(!pte || pte_none(*pte));
-
- page = &pte_page(*pte)[vpfn % (HPAGE_SIZE/PAGE_SIZE)];
-
- WARN_ON(!PageCompound(page));
-
- get_page(page);
- pages[i] = page;
- }
-
- if (vmas)
- vmas[i] = vma;
-
- vaddr += PAGE_SIZE;
- ++vpfn;
- --remainder;
- ++i;
- }
-
- *length = remainder;
- *position = vaddr;
-
- return i;
-}
-
struct page *
follow_huge_addr(struct mm_struct *mm, unsigned long address, int write)
{
return NULL;
}
-void unmap_hugepage_range(struct vm_area_struct *vma,
- unsigned long start, unsigned long end)
-{
- struct mm_struct *mm = vma->vm_mm;
- unsigned long addr;
- pte_t *ptep;
- struct page *page;
-
- WARN_ON(!is_vm_hugetlb_page(vma));
- BUG_ON((start % HPAGE_SIZE) != 0);
- BUG_ON((end % HPAGE_SIZE) != 0);
-
- for (addr = start; addr < end; addr += HPAGE_SIZE) {
- pte_t pte;
-
- ptep = huge_pte_offset(mm, addr);
- if (!ptep || pte_none(*ptep))
- continue;
-
- pte = *ptep;
- page = pte_page(pte);
- pte_clear(mm, addr, ptep);
-
- put_page(page);
- }
- add_mm_counter(mm, rss, -((end - start) >> PAGE_SHIFT));
- flush_tlb_pending();
-}
-
-int hugetlb_prefault(struct address_space *mapping, struct vm_area_struct *vma)
-{
- struct mm_struct *mm = current->mm;
- unsigned long addr;
- int ret = 0;
-
- WARN_ON(!is_vm_hugetlb_page(vma));
- BUG_ON((vma->vm_start % HPAGE_SIZE) != 0);
- BUG_ON((vma->vm_end % HPAGE_SIZE) != 0);
-
- spin_lock(&mm->page_table_lock);
- for (addr = vma->vm_start; addr < vma->vm_end; addr += HPAGE_SIZE) {
- unsigned long idx;
- pte_t *pte = huge_pte_alloc(mm, addr);
- struct page *page;
-
- if (!pte) {
- ret = -ENOMEM;
- goto out;
- }
- if (! pte_none(*pte))
- continue;
-
- idx = ((addr - vma->vm_start) >> HPAGE_SHIFT)
- + (vma->vm_pgoff >> (HPAGE_SHIFT - PAGE_SHIFT));
- page = find_get_page(mapping, idx);
- if (!page) {
- /* charge the fs quota first */
- if (hugetlb_get_quota(mapping)) {
- ret = -ENOMEM;
- goto out;
- }
- page = alloc_huge_page();
- if (!page) {
- hugetlb_put_quota(mapping);
- ret = -ENOMEM;
- goto out;
- }
- ret = add_to_page_cache(page, mapping, idx, GFP_ATOMIC);
- if (! ret) {
- unlock_page(page);
- } else {
- hugetlb_put_quota(mapping);
- free_huge_page(page);
- goto out;
- }
- }
- set_huge_pte(mm, vma, addr, page, pte, vma->vm_flags & VM_WRITE);
- }
-out:
- spin_unlock(&mm->page_table_lock);
- return ret;
-}
-
/* Because we have an exclusive hugepage region which lies within the
* normal user address space, we have to take special measures to make
* non-huge mmap()s evade the hugepage reserved regions. */
#include <asm/tlbflush.h>
#include <asm/cacheflush.h>
-static pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr)
+pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr)
{
pgd_t *pgd;
pmd_t *pmd;
return pte;
}
-static pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
+pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
{
pgd_t *pgd;
pmd_t *pmd;
#define mk_pte_huge(entry) do { pte_val(entry) |= _PAGE_SZHUGE; } while (0)
-static void set_huge_pte(struct mm_struct *mm, struct vm_area_struct *vma,
- struct page *page, pte_t * page_table, int write_access)
+void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t entry)
{
- unsigned long i;
- pte_t entry;
+ int i;
- add_mm_counter(mm, rss, HPAGE_SIZE / PAGE_SIZE);
+ for (i = 0; i < (1 << HUGETLB_PAGE_ORDER); i++) {
+ set_pte_at(mm, addr, ptep, entry);
+ ptep++;
+ addr += PAGE_SIZE;
+ pte_val(entry) += PAGE_SIZE;
+ }
+}
- if (write_access)
- entry = pte_mkwrite(pte_mkdirty(mk_pte(page,
- vma->vm_page_prot)));
- else
- entry = pte_wrprotect(mk_pte(page, vma->vm_page_prot));
- entry = pte_mkyoung(entry);
- mk_pte_huge(entry);
+pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep)
+{
+ pte_t entry;
+ int i;
- for (i = 0; i < (1 << HUGETLB_PAGE_ORDER); i++) {
- set_pte(page_table, entry);
- page_table++;
+ entry = *ptep;
- pte_val(entry) += PAGE_SIZE;
+ for (i = 0; i < (1 << HUGETLB_PAGE_ORDER); i++) {
+ pte_clear(mm, addr, ptep);
+ addr += PAGE_SIZE;
+ ptep++;
}
+
+ return entry;
}
/*
return 0;
}
-int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src,
- struct vm_area_struct *vma)
-{
- pte_t *src_pte, *dst_pte, entry;
- struct page *ptepage;
- unsigned long addr = vma->vm_start;
- unsigned long end = vma->vm_end;
- int i;
-
- while (addr < end) {
- dst_pte = huge_pte_alloc(dst, addr);
- if (!dst_pte)
- goto nomem;
- src_pte = huge_pte_offset(src, addr);
- BUG_ON(!src_pte || pte_none(*src_pte));
- entry = *src_pte;
- ptepage = pte_page(entry);
- get_page(ptepage);
- for (i = 0; i < (1 << HUGETLB_PAGE_ORDER); i++) {
- set_pte(dst_pte, entry);
- pte_val(entry) += PAGE_SIZE;
- dst_pte++;
- }
- add_mm_counter(dst, rss, HPAGE_SIZE / PAGE_SIZE);
- addr += HPAGE_SIZE;
- }
- return 0;
-
-nomem:
- return -ENOMEM;
-}
-
-int follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma,
- struct page **pages, struct vm_area_struct **vmas,
- unsigned long *position, int *length, int i)
-{
- unsigned long vaddr = *position;
- int remainder = *length;
-
- WARN_ON(!is_vm_hugetlb_page(vma));
-
- while (vaddr < vma->vm_end && remainder) {
- if (pages) {
- pte_t *pte;
- struct page *page;
-
- pte = huge_pte_offset(mm, vaddr);
-
- /* hugetlb should be locked, and hence, prefaulted */
- BUG_ON(!pte || pte_none(*pte));
-
- page = pte_page(*pte);
-
- WARN_ON(!PageCompound(page));
-
- get_page(page);
- pages[i] = page;
- }
-
- if (vmas)
- vmas[i] = vma;
-
- vaddr += PAGE_SIZE;
- --remainder;
- ++i;
- }
-
- *length = remainder;
- *position = vaddr;
-
- return i;
-}
-
struct page *follow_huge_addr(struct mm_struct *mm,
unsigned long address, int write)
{
{
return NULL;
}
-
-void unmap_hugepage_range(struct vm_area_struct *vma,
- unsigned long start, unsigned long end)
-{
- struct mm_struct *mm = vma->vm_mm;
- unsigned long address;
- pte_t *pte;
- struct page *page;
- int i;
-
- BUG_ON(start & (HPAGE_SIZE - 1));
- BUG_ON(end & (HPAGE_SIZE - 1));
-
- for (address = start; address < end; address += HPAGE_SIZE) {
- pte = huge_pte_offset(mm, address);
- BUG_ON(!pte);
- if (pte_none(*pte))
- continue;
- page = pte_page(*pte);
- put_page(page);
- for (i = 0; i < (1 << HUGETLB_PAGE_ORDER); i++) {
- pte_clear(mm, address+(i*PAGE_SIZE), pte);
- pte++;
- }
- }
- add_mm_counter(mm, rss, -((end - start) >> PAGE_SHIFT));
- flush_tlb_range(vma, start, end);
-}
-
-int hugetlb_prefault(struct address_space *mapping, struct vm_area_struct *vma)
-{
- struct mm_struct *mm = current->mm;
- unsigned long addr;
- int ret = 0;
-
- BUG_ON(vma->vm_start & ~HPAGE_MASK);
- BUG_ON(vma->vm_end & ~HPAGE_MASK);
-
- spin_lock(&mm->page_table_lock);
- for (addr = vma->vm_start; addr < vma->vm_end; addr += HPAGE_SIZE) {
- unsigned long idx;
- pte_t *pte = huge_pte_alloc(mm, addr);
- struct page *page;
-
- if (!pte) {
- ret = -ENOMEM;
- goto out;
- }
- if (!pte_none(*pte))
- continue;
-
- idx = ((addr - vma->vm_start) >> HPAGE_SHIFT)
- + (vma->vm_pgoff >> (HPAGE_SHIFT - PAGE_SHIFT));
- page = find_get_page(mapping, idx);
- if (!page) {
- /* charge the fs quota first */
- if (hugetlb_get_quota(mapping)) {
- ret = -ENOMEM;
- goto out;
- }
- page = alloc_huge_page();
- if (!page) {
- hugetlb_put_quota(mapping);
- ret = -ENOMEM;
- goto out;
- }
- ret = add_to_page_cache(page, mapping, idx, GFP_ATOMIC);
- if (! ret) {
- unlock_page(page);
- } else {
- hugetlb_put_quota(mapping);
- free_huge_page(page);
- goto out;
- }
- }
- set_huge_pte(mm, vma, page, pte, vma->vm_flags & VM_WRITE);
- }
-out:
- spin_unlock(&mm->page_table_lock);
- return ret;
-}
#include <asm/tlbflush.h>
#include <asm/cacheflush.h>
-static pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr)
+pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr)
{
pgd_t *pgd;
pmd_t *pmd;
return pte;
}
-static pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
+pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
{
pgd_t *pgd;
pmd_t *pmd;
}
}
+pte_t huge_ptep_get_and_clear(pte_t *ptep)
+{
+ pte_t entry;
+
+ entry = *ptep;
+
+ for (i = 0; i < (1 << HUGETLB_PAGE_ORDER); i++) {
+ pte_clear(pte);
+ pte++;
+ }
+
+ return entry;
+}
+
/*
* This function checks for proper alignment of input addr and len parameters.
*/
#include <asm/cacheflush.h>
#include <asm/mmu_context.h>
-static pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr)
+pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr)
{
pgd_t *pgd;
pud_t *pud;
return pte;
}
-static pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
+pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
{
pgd_t *pgd;
pud_t *pud;
#define mk_pte_huge(entry) do { pte_val(entry) |= _PAGE_SZHUGE; } while (0)
-static void set_huge_pte(struct mm_struct *mm, struct vm_area_struct *vma,
- unsigned long addr,
- struct page *page, pte_t * page_table, int write_access)
+void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t entry)
{
- unsigned long i;
- pte_t entry;
+ int i;
+
+ for (i = 0; i < (1 << HUGETLB_PAGE_ORDER); i++) {
+ set_pte_at(mm, addr, ptep, entry);
+ ptep++;
+ addr += PAGE_SIZE;
+ pte_val(entry) += PAGE_SIZE;
+ }
+}
- add_mm_counter(mm, rss, HPAGE_SIZE / PAGE_SIZE);
+pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep)
+{
+ pte_t entry;
+ int i;
- if (write_access)
- entry = pte_mkwrite(pte_mkdirty(mk_pte(page,
- vma->vm_page_prot)));
- else
- entry = pte_wrprotect(mk_pte(page, vma->vm_page_prot));
- entry = pte_mkyoung(entry);
- mk_pte_huge(entry);
+ entry = *ptep;
for (i = 0; i < (1 << HUGETLB_PAGE_ORDER); i++) {
- set_pte_at(mm, addr, page_table, entry);
- page_table++;
+ pte_clear(mm, addr, ptep);
addr += PAGE_SIZE;
-
- pte_val(entry) += PAGE_SIZE;
+ ptep++;
}
+
+ return entry;
}
/*
return 0;
}
-int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src,
- struct vm_area_struct *vma)
-{
- pte_t *src_pte, *dst_pte, entry;
- struct page *ptepage;
- unsigned long addr = vma->vm_start;
- unsigned long end = vma->vm_end;
- int i;
-
- while (addr < end) {
- dst_pte = huge_pte_alloc(dst, addr);
- if (!dst_pte)
- goto nomem;
- src_pte = huge_pte_offset(src, addr);
- BUG_ON(!src_pte || pte_none(*src_pte));
- entry = *src_pte;
- ptepage = pte_page(entry);
- get_page(ptepage);
- for (i = 0; i < (1 << HUGETLB_PAGE_ORDER); i++) {
- set_pte_at(dst, addr, dst_pte, entry);
- pte_val(entry) += PAGE_SIZE;
- dst_pte++;
- addr += PAGE_SIZE;
- }
- add_mm_counter(dst, rss, HPAGE_SIZE / PAGE_SIZE);
- }
- return 0;
-
-nomem:
- return -ENOMEM;
-}
-
-int follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma,
- struct page **pages, struct vm_area_struct **vmas,
- unsigned long *position, int *length, int i)
-{
- unsigned long vaddr = *position;
- int remainder = *length;
-
- WARN_ON(!is_vm_hugetlb_page(vma));
-
- while (vaddr < vma->vm_end && remainder) {
- if (pages) {
- pte_t *pte;
- struct page *page;
-
- pte = huge_pte_offset(mm, vaddr);
-
- /* hugetlb should be locked, and hence, prefaulted */
- BUG_ON(!pte || pte_none(*pte));
-
- page = pte_page(*pte);
-
- WARN_ON(!PageCompound(page));
-
- get_page(page);
- pages[i] = page;
- }
-
- if (vmas)
- vmas[i] = vma;
-
- vaddr += PAGE_SIZE;
- --remainder;
- ++i;
- }
-
- *length = remainder;
- *position = vaddr;
-
- return i;
-}
-
struct page *follow_huge_addr(struct mm_struct *mm,
unsigned long address, int write)
{
return NULL;
}
-void unmap_hugepage_range(struct vm_area_struct *vma,
- unsigned long start, unsigned long end)
-{
- struct mm_struct *mm = vma->vm_mm;
- unsigned long address;
- pte_t *pte;
- struct page *page;
- int i;
-
- BUG_ON(start & (HPAGE_SIZE - 1));
- BUG_ON(end & (HPAGE_SIZE - 1));
-
- for (address = start; address < end; address += HPAGE_SIZE) {
- pte = huge_pte_offset(mm, address);
- BUG_ON(!pte);
- if (pte_none(*pte))
- continue;
- page = pte_page(*pte);
- put_page(page);
- for (i = 0; i < (1 << HUGETLB_PAGE_ORDER); i++) {
- pte_clear(mm, address+(i*PAGE_SIZE), pte);
- pte++;
- }
- }
- add_mm_counter(mm, rss, -((end - start) >> PAGE_SHIFT));
- flush_tlb_range(vma, start, end);
-}
-
static void context_reload(void *__data)
{
struct mm_struct *mm = __data;
load_secondary_context(mm);
}
-int hugetlb_prefault(struct address_space *mapping, struct vm_area_struct *vma)
+void hugetlb_prefault_arch_hook(struct mm_struct *mm)
{
- struct mm_struct *mm = current->mm;
- unsigned long addr;
- int ret = 0;
-
/* On UltraSPARC-III+ and later, configure the second half of
* the Data-TLB for huge pages.
*/
}
spin_unlock(&ctx_alloc_lock);
}
-
- BUG_ON(vma->vm_start & ~HPAGE_MASK);
- BUG_ON(vma->vm_end & ~HPAGE_MASK);
-
- spin_lock(&mm->page_table_lock);
- for (addr = vma->vm_start; addr < vma->vm_end; addr += HPAGE_SIZE) {
- unsigned long idx;
- pte_t *pte = huge_pte_alloc(mm, addr);
- struct page *page;
-
- if (!pte) {
- ret = -ENOMEM;
- goto out;
- }
- if (!pte_none(*pte))
- continue;
-
- idx = ((addr - vma->vm_start) >> HPAGE_SHIFT)
- + (vma->vm_pgoff >> (HPAGE_SHIFT - PAGE_SHIFT));
- page = find_get_page(mapping, idx);
- if (!page) {
- /* charge the fs quota first */
- if (hugetlb_get_quota(mapping)) {
- ret = -ENOMEM;
- goto out;
- }
- page = alloc_huge_page();
- if (!page) {
- hugetlb_put_quota(mapping);
- ret = -ENOMEM;
- goto out;
- }
- ret = add_to_page_cache(page, mapping, idx, GFP_ATOMIC);
- if (! ret) {
- unlock_page(page);
- } else {
- hugetlb_put_quota(mapping);
- free_huge_page(page);
- goto out;
- }
- }
- set_huge_pte(mm, vma, addr, page, pte, vma->vm_flags & VM_WRITE);
- }
-out:
- spin_unlock(&mm->page_table_lock);
- return ret;
}
#define HPAGE_MASK (~(HPAGE_SIZE - 1))
#define HUGETLB_PAGE_ORDER (HPAGE_SHIFT - PAGE_SHIFT)
#define HAVE_ARCH_HUGETLB_UNMAPPED_AREA
+#define ARCH_HAS_HUGETLB_CLEAN_STALE_PGTABLE
#endif
#define pgd_val(x) ((x).pgd)
static inline pte_t pte_mkdirty(pte_t pte) { (pte).pte_low |= _PAGE_DIRTY; return pte; }
static inline pte_t pte_mkyoung(pte_t pte) { (pte).pte_low |= _PAGE_ACCESSED; return pte; }
static inline pte_t pte_mkwrite(pte_t pte) { (pte).pte_low |= _PAGE_RW; return pte; }
+static inline pte_t pte_mkhuge(pte_t pte) { (pte).pte_low |= _PAGE_PRESENT | _PAGE_PSE; return pte; }
#ifdef CONFIG_X86_PAE
# include <asm/pgtable-3level.h>
*/
#define mk_pte(page, pgprot) pfn_pte(page_to_pfn(page), (pgprot))
-#define mk_pte_huge(entry) ((entry).pte_low |= _PAGE_PRESENT | _PAGE_PSE)
static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
{
#define pte_mkyoung(pte) (__pte(pte_val(pte) | _PAGE_A))
#define pte_mkclean(pte) (__pte(pte_val(pte) & ~_PAGE_D))
#define pte_mkdirty(pte) (__pte(pte_val(pte) | _PAGE_D))
+#define pte_mkhuge(pte) (__pte(pte_val(pte) | _PAGE_P))
/*
* Macro to a page protection value as "uncacheable". Note that "protection" is really a
#define HPAGE_SIZE (1UL << HPAGE_SHIFT)
#define HPAGE_MASK (~(HPAGE_SIZE-1))
#define HUGETLB_PAGE_ORDER (HPAGE_SHIFT-PAGE_SHIFT)
+#define ARCH_HAS_SETCLEAR_HUGE_PTE
#endif
#ifdef __KERNEL__
static inline pte_t pte_mkdirty(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) | _PAGE_DIRTY)); return pte; }
static inline pte_t pte_mkyoung(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) | _PAGE_ACCESSED)); return pte; }
static inline pte_t pte_mkwrite(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) | _PAGE_RW)); return pte; }
+static inline pte_t pte_mkhuge(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) | _PAGE_SZHUGE)); return pte; }
/*
* Macro and implementation to make a page protection as uncachable.
#define HPAGE_SIZE (1UL << HPAGE_SHIFT)
#define HPAGE_MASK (~(HPAGE_SIZE-1))
#define HUGETLB_PAGE_ORDER (HPAGE_SHIFT-PAGE_SHIFT)
+#define ARCH_HAS_SETCLEAR_HUGE_PTE
#endif
#ifdef __KERNEL__
extern inline pte_t pte_mkexec(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) | _PAGE_EXECUTE)); return pte; }
extern inline pte_t pte_mkdirty(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) | _PAGE_DIRTY)); return pte; }
extern inline pte_t pte_mkyoung(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) | _PAGE_ACCESSED)); return pte; }
+extern inline pte_t pte_mkhuge(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) | _PAGE_SZHUGE)); return pte; }
+
/*
* Conversion functions: convert a page and protection to a page entry.
#define HPAGE_SIZE (_AC(1,UL) << HPAGE_SHIFT)
#define HPAGE_MASK (~(HPAGE_SIZE - 1UL))
#define HUGETLB_PAGE_ORDER (HPAGE_SHIFT - PAGE_SHIFT)
+#define ARCH_HAS_SETCLEAR_HUGE_PTE
+#define ARCH_HAS_HUGETLB_PREFAULT_HOOK
#endif
#define TASK_UNMAPPED_BASE (test_thread_flag(TIF_32BIT) ? \
#define pte_mkyoung(pte) (__pte(pte_val(pte) | _PAGE_ACCESSED | _PAGE_R))
#define pte_mkwrite(pte) (__pte(pte_val(pte) | _PAGE_WRITE))
#define pte_mkdirty(pte) (__pte(pte_val(pte) | _PAGE_MODIFIED | _PAGE_W))
+#define pte_mkhuge(pte) (__pte(pte_val(pte) | _PAGE_SZHUGE))
/* to find an entry in a page-table-directory. */
#define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1))
#define HPAGE_SIZE ((1UL) << HPAGE_SHIFT)
#define HPAGE_MASK (~(HPAGE_SIZE - 1))
#define HUGETLB_PAGE_ORDER (HPAGE_SHIFT - PAGE_SHIFT)
+#define ARCH_HAS_HUGETLB_CLEAN_STALE_PGTABLE
#ifdef __KERNEL__
#ifndef __ASSEMBLY__
extern inline int pte_write(pte_t pte) { return pte_val(pte) & _PAGE_RW; }
static inline int pte_file(pte_t pte) { return pte_val(pte) & _PAGE_FILE; }
+#define __LARGE_PTE (_PAGE_PSE|_PAGE_PRESENT)
extern inline pte_t pte_rdprotect(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) & ~_PAGE_USER)); return pte; }
extern inline pte_t pte_exprotect(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) & ~_PAGE_USER)); return pte; }
extern inline pte_t pte_mkclean(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) & ~_PAGE_DIRTY)); return pte; }
extern inline pte_t pte_mkdirty(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) | _PAGE_DIRTY)); return pte; }
extern inline pte_t pte_mkyoung(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) | _PAGE_ACCESSED)); return pte; }
extern inline pte_t pte_mkwrite(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) | _PAGE_RW)); return pte; }
+extern inline pte_t pte_mkhuge(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) | __LARGE_PTE)); return pte; }
struct vm_area_struct;
*/
#define pgprot_noncached(prot) (__pgprot(pgprot_val(prot) | _PAGE_PCD | _PAGE_PWT))
-#define __LARGE_PTE (_PAGE_PSE|_PAGE_PRESENT)
static inline int pmd_large(pmd_t pte) {
return (pmd_val(pte) & __LARGE_PTE) == __LARGE_PTE;
}
#ifdef CONFIG_HUGETLB_PAGE
#include <linux/mempolicy.h>
+#include <asm/tlbflush.h>
struct ctl_table;
int hugetlb_report_node_meminfo(int, char *);
int is_hugepage_mem_enough(size_t);
unsigned long hugetlb_total_pages(void);
-struct page *follow_huge_addr(struct mm_struct *mm, unsigned long address,
- int write);
-struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address,
- pmd_t *pmd, int write);
-int is_aligned_hugepage_range(unsigned long addr, unsigned long len);
-int pmd_huge(pmd_t pmd);
struct page *alloc_huge_page(void);
void free_huge_page(struct page *);
extern const unsigned long hugetlb_zero, hugetlb_infinity;
extern int sysctl_hugetlb_shm_group;
+/* arch callbacks */
+
+pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr);
+pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr);
+struct page *follow_huge_addr(struct mm_struct *mm, unsigned long address,
+ int write);
+struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address,
+ pmd_t *pmd, int write);
+int is_aligned_hugepage_range(unsigned long addr, unsigned long len);
+int pmd_huge(pmd_t pmd);
+
#ifndef ARCH_HAS_HUGEPAGE_ONLY_RANGE
#define is_hugepage_only_range(mm, addr, len) 0
#define hugetlb_free_pgd_range(tlb, addr, end, floor, ceiling) \
int prepare_hugepage_range(unsigned long addr, unsigned long len);
#endif
+#ifndef ARCH_HAS_SETCLEAR_HUGE_PTE
+#define set_huge_pte_at(mm, addr, ptep, pte) set_pte_at(mm, addr, ptep, pte)
+#define huge_ptep_get_and_clear(mm, addr, ptep) ptep_get_and_clear(mm, addr, ptep)
+#else
+void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t pte);
+pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep);
+#endif
+
+#ifndef ARCH_HAS_HUGETLB_PREFAULT_HOOK
+#define hugetlb_prefault_arch_hook(mm) do { } while (0)
+#else
+void hugetlb_prefault_arch_hook(struct mm_struct *mm);
+#endif
+
+#ifndef ARCH_HAS_HUGETLB_CLEAN_STALE_PGTABLE
+#define hugetlb_clean_stale_pgtable(pte) BUG()
+#else
+void hugetlb_clean_stale_pgtable(pte_t *pte);
+#endif
+
#else /* !CONFIG_HUGETLB_PAGE */
static inline int is_vm_hugetlb_page(struct vm_area_struct *vma)
#include <linux/init.h>
#include <linux/module.h>
#include <linux/mm.h>
-#include <linux/hugetlb.h>
#include <linux/sysctl.h>
#include <linux/highmem.h>
#include <linux/nodemask.h>
+#include <linux/pagemap.h>
+#include <asm/page.h>
+#include <asm/pgtable.h>
+
+#include <linux/hugetlb.h>
const unsigned long hugetlb_zero = 0, hugetlb_infinity = ~0UL;
static unsigned long nr_huge_pages, free_huge_pages;
.nopage = hugetlb_nopage,
};
+static pte_t make_huge_pte(struct vm_area_struct *vma, struct page *page)
+{
+ pte_t entry;
+
+ if (vma->vm_flags & VM_WRITE) {
+ entry =
+ pte_mkwrite(pte_mkdirty(mk_pte(page, vma->vm_page_prot)));
+ } else {
+ entry = pte_wrprotect(mk_pte(page, vma->vm_page_prot));
+ }
+ entry = pte_mkyoung(entry);
+ entry = pte_mkhuge(entry);
+
+ return entry;
+}
+
+int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src,
+ struct vm_area_struct *vma)
+{
+ pte_t *src_pte, *dst_pte, entry;
+ struct page *ptepage;
+ unsigned long addr = vma->vm_start;
+ unsigned long end = vma->vm_end;
+
+ while (addr < end) {
+ dst_pte = huge_pte_alloc(dst, addr);
+ if (!dst_pte)
+ goto nomem;
+ src_pte = huge_pte_offset(src, addr);
+ BUG_ON(!src_pte || pte_none(*src_pte)); /* prefaulted */
+ entry = *src_pte;
+ ptepage = pte_page(entry);
+ get_page(ptepage);
+ add_mm_counter(dst, rss, HPAGE_SIZE / PAGE_SIZE);
+ set_huge_pte_at(dst, addr, dst_pte, entry);
+ addr += HPAGE_SIZE;
+ }
+ return 0;
+
+nomem:
+ return -ENOMEM;
+}
+
+void unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start,
+ unsigned long end)
+{
+ struct mm_struct *mm = vma->vm_mm;
+ unsigned long address;
+ pte_t pte;
+ struct page *page;
+
+ WARN_ON(!is_vm_hugetlb_page(vma));
+ BUG_ON(start & ~HPAGE_MASK);
+ BUG_ON(end & ~HPAGE_MASK);
+
+ for (address = start; address < end; address += HPAGE_SIZE) {
+ pte = huge_ptep_get_and_clear(mm, address, huge_pte_offset(mm, address));
+ if (pte_none(pte))
+ continue;
+ page = pte_page(pte);
+ put_page(page);
+ }
+ add_mm_counter(mm, rss, -((end - start) >> PAGE_SHIFT));
+ flush_tlb_range(vma, start, end);
+}
+
void zap_hugepage_range(struct vm_area_struct *vma,
unsigned long start, unsigned long length)
{
unmap_hugepage_range(vma, start, start + length);
spin_unlock(&mm->page_table_lock);
}
+
+int hugetlb_prefault(struct address_space *mapping, struct vm_area_struct *vma)
+{
+ struct mm_struct *mm = current->mm;
+ unsigned long addr;
+ int ret = 0;
+
+ WARN_ON(!is_vm_hugetlb_page(vma));
+ BUG_ON(vma->vm_start & ~HPAGE_MASK);
+ BUG_ON(vma->vm_end & ~HPAGE_MASK);
+
+ hugetlb_prefault_arch_hook(mm);
+
+ spin_lock(&mm->page_table_lock);
+ for (addr = vma->vm_start; addr < vma->vm_end; addr += HPAGE_SIZE) {
+ unsigned long idx;
+ pte_t *pte = huge_pte_alloc(mm, addr);
+ struct page *page;
+
+ if (!pte) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ if (! pte_none(*pte))
+ hugetlb_clean_stale_pgtable(pte);
+
+ idx = ((addr - vma->vm_start) >> HPAGE_SHIFT)
+ + (vma->vm_pgoff >> (HPAGE_SHIFT - PAGE_SHIFT));
+ page = find_get_page(mapping, idx);
+ if (!page) {
+ /* charge the fs quota first */
+ if (hugetlb_get_quota(mapping)) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ page = alloc_huge_page();
+ if (!page) {
+ hugetlb_put_quota(mapping);
+ ret = -ENOMEM;
+ goto out;
+ }
+ ret = add_to_page_cache(page, mapping, idx, GFP_ATOMIC);
+ if (! ret) {
+ unlock_page(page);
+ } else {
+ hugetlb_put_quota(mapping);
+ free_huge_page(page);
+ goto out;
+ }
+ }
+ add_mm_counter(mm, rss, HPAGE_SIZE / PAGE_SIZE);
+ set_huge_pte_at(mm, addr, pte, make_huge_pte(vma, page));
+ }
+out:
+ spin_unlock(&mm->page_table_lock);
+ return ret;
+}
+
+int follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma,
+ struct page **pages, struct vm_area_struct **vmas,
+ unsigned long *position, int *length, int i)
+{
+ unsigned long vpfn, vaddr = *position;
+ int remainder = *length;
+
+ BUG_ON(!is_vm_hugetlb_page(vma));
+
+ vpfn = vaddr/PAGE_SIZE;
+ while (vaddr < vma->vm_end && remainder) {
+
+ if (pages) {
+ pte_t *pte;
+ struct page *page;
+
+ /* Some archs (sparc64, sh*) have multiple
+ * pte_ts to each hugepage. We have to make
+ * sure we get the first, for the page
+ * indexing below to work. */
+ pte = huge_pte_offset(mm, vaddr & HPAGE_MASK);
+
+ /* hugetlb should be locked, and hence, prefaulted */
+ WARN_ON(!pte || pte_none(*pte));
+
+ page = &pte_page(*pte)[vpfn % (HPAGE_SIZE/PAGE_SIZE)];
+
+ WARN_ON(!PageCompound(page));
+
+ get_page(page);
+ pages[i] = page;
+ }
+
+ if (vmas)
+ vmas[i] = vma;
+
+ vaddr += PAGE_SIZE;
+ ++vpfn;
+ --remainder;
+ ++i;
+ }
+
+ *length = remainder;
+ *position = vaddr;
+
+ return i;
+}