/* Handle un-addressable ZONE_DEVICE memory */
entry = pte_to_swp_entry(*pvmw->pte);
- if (!is_device_private_entry(entry))
+ if (!is_device_private_entry(entry) &&
+ !is_device_exclusive_entry(entry))
return false;
} else if (!pte_present(*pvmw->pte))
return false;
return false;
entry = pte_to_swp_entry(*pvmw->pte);
- if (!is_migration_entry(entry))
+ if (!is_migration_entry(entry) &&
+ !is_device_exclusive_entry(entry))
return false;
- pfn = migration_entry_to_pfn(entry);
+ pfn = swp_offset(entry);
} else if (is_swap_pte(*pvmw->pte)) {
swp_entry_t entry;
/* Handle un-addressable ZONE_DEVICE memory */
entry = pte_to_swp_entry(*pvmw->pte);
- if (!is_device_private_entry(entry))
+ if (!is_device_private_entry(entry) &&
+ !is_device_exclusive_entry(entry))
return false;
- pfn = device_private_entry_to_pfn(entry);
+ pfn = swp_offset(entry);
} else {
if (!pte_present(*pvmw->pte))
return false;
return pfn_is_match(pvmw->page, pfn);
}
+static void step_forward(struct page_vma_mapped_walk *pvmw, unsigned long size)
+{
+ pvmw->address = (pvmw->address + size) & ~(size - 1);
+ if (!pvmw->address)
+ pvmw->address = ULONG_MAX;
+}
+
/**
* page_vma_mapped_walk - check if @pvmw->page is mapped in @pvmw->vma at
* @pvmw->address
{
struct mm_struct *mm = pvmw->vma->vm_mm;
struct page *page = pvmw->page;
+ unsigned long end;
pgd_t *pgd;
p4d_t *p4d;
pud_t *pud;
if (pvmw->pmd && !pvmw->pte)
return not_found(pvmw);
- if (pvmw->pte)
- goto next_pte;
+ if (unlikely(PageHuge(page))) {
+ /* The only possible mapping was handled on last iteration */
+ if (pvmw->pte)
+ return not_found(pvmw);
- if (unlikely(PageHuge(pvmw->page))) {
/* when pud is not present, pte will be NULL */
pvmw->pte = huge_pte_offset(mm, pvmw->address, page_size(page));
if (!pvmw->pte)
return not_found(pvmw);
return true;
}
-restart:
- pgd = pgd_offset(mm, pvmw->address);
- if (!pgd_present(*pgd))
- return false;
- p4d = p4d_offset(pgd, pvmw->address);
- if (!p4d_present(*p4d))
- return false;
- pud = pud_offset(p4d, pvmw->address);
- if (!pud_present(*pud))
- return false;
- pvmw->pmd = pmd_offset(pud, pvmw->address);
+
/*
- * Make sure the pmd value isn't cached in a register by the
- * compiler and used as a stale value after we've observed a
- * subsequent update.
+ * Seek to next pte only makes sense for THP.
+ * But more important than that optimization, is to filter out
+ * any PageKsm page: whose page->index misleads vma_address()
+ * and vma_address_end() to disaster.
*/
- pmde = READ_ONCE(*pvmw->pmd);
- if (pmd_trans_huge(pmde) || is_pmd_migration_entry(pmde)) {
- pvmw->ptl = pmd_lock(mm, pvmw->pmd);
- if (likely(pmd_trans_huge(*pvmw->pmd))) {
- if (pvmw->flags & PVMW_MIGRATION)
- return not_found(pvmw);
- if (pmd_page(*pvmw->pmd) != page)
- return not_found(pvmw);
- return true;
- } else if (!pmd_present(*pvmw->pmd)) {
- if (thp_migration_supported()) {
- if (!(pvmw->flags & PVMW_MIGRATION))
+ end = PageTransCompound(page) ?
+ vma_address_end(page, pvmw->vma) :
+ pvmw->address + PAGE_SIZE;
+ if (pvmw->pte)
+ goto next_pte;
+restart:
+ do {
+ pgd = pgd_offset(mm, pvmw->address);
+ if (!pgd_present(*pgd)) {
+ step_forward(pvmw, PGDIR_SIZE);
+ continue;
+ }
+ p4d = p4d_offset(pgd, pvmw->address);
+ if (!p4d_present(*p4d)) {
+ step_forward(pvmw, P4D_SIZE);
+ continue;
+ }
+ pud = pud_offset(p4d, pvmw->address);
+ if (!pud_present(*pud)) {
+ step_forward(pvmw, PUD_SIZE);
+ continue;
+ }
+
+ pvmw->pmd = pmd_offset(pud, pvmw->address);
+ /*
+ * Make sure the pmd value isn't cached in a register by the
+ * compiler and used as a stale value after we've observed a
+ * subsequent update.
+ */
+ pmde = READ_ONCE(*pvmw->pmd);
+
+ if (pmd_trans_huge(pmde) || is_pmd_migration_entry(pmde)) {
+ pvmw->ptl = pmd_lock(mm, pvmw->pmd);
+ pmde = *pvmw->pmd;
+ if (likely(pmd_trans_huge(pmde))) {
+ if (pvmw->flags & PVMW_MIGRATION)
return not_found(pvmw);
- if (is_migration_entry(pmd_to_swp_entry(*pvmw->pmd))) {
- swp_entry_t entry = pmd_to_swp_entry(*pvmw->pmd);
+ if (pmd_page(pmde) != page)
+ return not_found(pvmw);
+ return true;
+ }
+ if (!pmd_present(pmde)) {
+ swp_entry_t entry;
- if (migration_entry_to_page(entry) != page)
- return not_found(pvmw);
- return true;
- }
+ if (!thp_migration_supported() ||
+ !(pvmw->flags & PVMW_MIGRATION))
+ return not_found(pvmw);
+ entry = pmd_to_swp_entry(pmde);
+ if (!is_migration_entry(entry) ||
+ pfn_swap_entry_to_page(entry) != page)
+ return not_found(pvmw);
+ return true;
}
- return not_found(pvmw);
- } else {
/* THP pmd was split under us: handle on pte level */
spin_unlock(pvmw->ptl);
pvmw->ptl = NULL;
- }
- } else if (!pmd_present(pmde)) {
- /*
- * If PVMW_SYNC, take and drop THP pmd lock so that we
- * cannot return prematurely, while zap_huge_pmd() has
- * cleared *pmd but not decremented compound_mapcount().
- */
- if ((pvmw->flags & PVMW_SYNC) &&
- PageTransCompound(pvmw->page)) {
- spinlock_t *ptl = pmd_lock(mm, pvmw->pmd);
+ } else if (!pmd_present(pmde)) {
+ /*
+ * If PVMW_SYNC, take and drop THP pmd lock so that we
+ * cannot return prematurely, while zap_huge_pmd() has
+ * cleared *pmd but not decremented compound_mapcount().
+ */
+ if ((pvmw->flags & PVMW_SYNC) &&
+ PageTransCompound(page)) {
+ spinlock_t *ptl = pmd_lock(mm, pvmw->pmd);
- spin_unlock(ptl);
+ spin_unlock(ptl);
+ }
+ step_forward(pvmw, PMD_SIZE);
+ continue;
}
- return false;
- }
- if (!map_pte(pvmw))
- goto next_pte;
- while (1) {
- unsigned long end;
-
+ if (!map_pte(pvmw))
+ goto next_pte;
+this_pte:
if (check_pte(pvmw))
return true;
next_pte:
- /* Seek to next pte only makes sense for THP */
- if (!PageTransHuge(pvmw->page) || PageHuge(pvmw->page))
- return not_found(pvmw);
- end = vma_address_end(pvmw->page, pvmw->vma);
do {
pvmw->address += PAGE_SIZE;
if (pvmw->address >= end)
return not_found(pvmw);
/* Did we cross page table boundary? */
- if (pvmw->address % PMD_SIZE == 0) {
- pte_unmap(pvmw->pte);
+ if ((pvmw->address & (PMD_SIZE - PAGE_SIZE)) == 0) {
if (pvmw->ptl) {
spin_unlock(pvmw->ptl);
pvmw->ptl = NULL;
}
+ pte_unmap(pvmw->pte);
+ pvmw->pte = NULL;
goto restart;
- } else {
- pvmw->pte++;
+ }
+ pvmw->pte++;
+ if ((pvmw->flags & PVMW_SYNC) && !pvmw->ptl) {
+ pvmw->ptl = pte_lockptr(mm, pvmw->pmd);
+ spin_lock(pvmw->ptl);
}
} while (pte_none(*pvmw->pte));
pvmw->ptl = pte_lockptr(mm, pvmw->pmd);
spin_lock(pvmw->ptl);
}
- }
+ goto this_pte;
+ } while (pvmw->address < end);
+
+ return false;
}
/**
projects / linux-2.6-microblaze.git / blobdiff