/* mmlist_lock and vma->vm_mm->page_table_lock are held */
static inline void unuse_pmd(struct vm_area_struct * vma, pmd_t *dir,
unsigned long address, unsigned long size, unsigned long offset,
swp_entry_t entry, struct page* page)
{
pte_t * pte;
unsigned long end;
if (pmd_none(*dir))
return;
if (pmd_bad(*dir)) {
pmd_ERROR(*dir);
pmd_clear(dir);
return;
}
pte = pte_offset(dir, address);
offset += address & PMD_MASK;
address &= ~PMD_MASK;
end = address + size;
if (end > PMD_SIZE)
end = PMD_SIZE;
do {
unuse_pte(vma, offset+address-vma->vm_start, pte, entry, page);
address += PAGE_SIZE;
pte++;
} while (address && (address < end));
}
/* mmlist_lock and vma->vm_mm->page_table_lock are held */
static inline void unuse_pmd(struct vm_area_struct * vma, pmd_t *dir,
unsigned long address, unsigned long size, unsigned long offset,
swp_entry_t entry, struct page* page)
{
struct pte_chain * pte_chain = NULL;
pte_t *pte, *mapping;
unsigned long end;
if (pmd_none(*dir))
return;
if (pmd_bad(*dir)) {
pmd_ERROR(*dir);
pmd_clear(dir);
return;
}
mapping = pte = pte_offset_map(dir, address);
offset += address & PMD_MASK;
address &= ~PMD_MASK;
end = address + size;
if (end > PMD_SIZE)
end = PMD_SIZE;
do {
/*
* FIXME: handle pte_chain_alloc() failures
*/
if (pte_chain == NULL)
pte_chain = pte_chain_alloc(GFP_ATOMIC);
unuse_pte(vma, offset+address-vma->vm_start,
pte, entry, page, &pte_chain);
address += PAGE_SIZE;
pte++;
} while (address && (address < end));
pte_unmap(mapping);
pte_chain_free(pte_chain);
}
static int unuse_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
unsigned long addr, unsigned long end,
swp_entry_t entry, struct page *page)
{
pte_t swp_pte = swp_entry_to_pte(entry);
pte_t *pte;
int ret = 0;
/*
* We don't actually need pte lock while scanning for swp_pte: since
* we hold page lock and mmap_sem, swp_pte cannot be inserted into the
* page table while we're scanning; though it could get zapped, and on
* some architectures (e.g. x86_32 with PAE) we might catch a glimpse
* of unmatched parts which look like swp_pte, so unuse_pte must
* recheck under pte lock. Scanning without pte lock lets it be
* preemptible whenever CONFIG_PREEMPT but not CONFIG_HIGHPTE.
*/
pte = pte_offset_map(pmd, addr);
do {
/*
* swapoff spends a _lot_ of time in this loop!
* Test inline before going to call unuse_pte.
*/
if (unlikely(pte_same(*pte, swp_pte))) {
pte_unmap(pte);
ret = unuse_pte(vma, pmd, addr, entry, page);
if (ret)
goto out;
pte = pte_offset_map(pmd, addr);
}
} while (pte++, addr += PAGE_SIZE, addr != end);
pte_unmap(pte - 1);
out:
return ret;
}
static inline int unuse_pmd(struct vm_area_struct * vma, pmd_t *dir,
unsigned long address, unsigned long size, unsigned long offset,
unsigned int type, unsigned long page)
{
pte_t * pte;
unsigned long end;
if (pmd_none(*dir))
return 0;
if (pmd_bad(*dir)) {
printk("unuse_pmd: bad pmd (%08lx)\n", pmd_val(*dir));
pmd_clear(dir);
return 0;
}
pte = pte_offset(dir, address);
offset += address & PMD_MASK;
address &= ~PMD_MASK;
end = address + size;
if (end > PMD_SIZE)
end = PMD_SIZE;
do {
if (unuse_pte(vma, offset+address-vma->vm_start, pte, type, page))
return 1;
address += PAGE_SIZE;
pte++;
} while (address < end);
return 0;
}
static int unuse_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
unsigned long addr, unsigned long end,
swp_entry_t entry, struct page *page)
{
pte_t swp_pte = swp_entry_to_pte(entry);
pte_t *pte;
spinlock_t *ptl;
int found = 0;
pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
do {
/*
* swapoff spends a _lot_ of time in this loop!
* Test inline before going to call unuse_pte.
*/
if (unlikely(pte_same(*pte, swp_pte))) {
unuse_pte(vma, pte++, addr, entry, page);
found = 1;
break;
}
} while (pte++, addr += PAGE_SIZE, addr != end);
pte_unmap_unlock(pte - 1, ptl);
return found;
}
