diff --git a/include/linux/swap.h b/include/linux/swap.h
index 7cee73ef4f15..1cf234e8df55 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -186,20 +186,6 @@ extern unsigned long shrink_all_memory(unsigned long nr_pages);
extern int vm_swappiness;
extern int remove_mapping(struct address_space *mapping, struct page *page);
-/* possible outcome of pageout() */
-typedef enum {
- /* failed to write page out, page is locked */
- PAGE_KEEP,
- /* move page to the active list, page is locked */
- PAGE_ACTIVATE,
- /* page has been sent to the disk successfully, page is unlocked */
- PAGE_SUCCESS,
- /* page is clean and locked */
- PAGE_CLEAN,
-} pageout_t;
-
-extern pageout_t pageout(struct page *page, struct address_space *mapping);
-
#ifdef CONFIG_NUMA
extern int zone_reclaim_mode;
extern int zone_reclaim_interval;
@@ -259,7 +245,6 @@ extern int remove_exclusive_swap_page(struct page *);
struct backing_dev_info;
extern spinlock_t swap_lock;
-extern int remove_vma_swap(struct vm_area_struct *vma, struct page *page);
/* linux/mm/thrash.c */
extern struct mm_struct * swap_token_mm;
diff --git a/mm/migrate.c b/mm/migrate.c
index 96b9546e69e0..b5000d463893 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -24,6 +24,7 @@
#include <linux/topology.h>
#include <linux/cpu.h>
#include <linux/cpuset.h>
+#include <linux/writeback.h>
#include "internal.h"
@@ -123,7 +124,7 @@ static inline int is_swap_pte(pte_t pte)
/*
* Restore a potential migration pte to a working pte entry
*/
-static void remove_migration_pte(struct vm_area_struct *vma, unsigned long addr,
+static void remove_migration_pte(struct vm_area_struct *vma,
struct page *old, struct page *new)
{
struct mm_struct *mm = vma->vm_mm;
@@ -133,6 +134,10 @@ static void remove_migration_pte(struct vm_area_struct *vma, unsigned long addr,
pmd_t *pmd;
pte_t *ptep, pte;
spinlock_t *ptl;
+ unsigned long addr = page_address_in_vma(new, vma);
+
+ if (addr == -EFAULT)
+ return;
pgd = pgd_offset(mm, addr);
if (!pgd_present(*pgd))
@@ -169,19 +174,47 @@ static void remove_migration_pte(struct vm_area_struct *vma, unsigned long addr,
if (is_write_migration_entry(entry))
pte = pte_mkwrite(pte);
set_pte_at(mm, addr, ptep, pte);
- page_add_anon_rmap(new, vma, addr);
+
+ if (PageAnon(new))
+ page_add_anon_rmap(new, vma, addr);
+ else
+ page_add_file_rmap(new);
+
+ /* No need to invalidate - it was non-present before */
+ update_mmu_cache(vma, addr, pte);
+ lazy_mmu_prot_update(pte);
+
out:
pte_unmap_unlock(ptep, ptl);
}
/*
- * Get rid of all migration entries and replace them by
- * references to the indicated page.
- *
+ * Note that remove_file_migration_ptes will only work on regular mappings,
+ * Nonlinear mappings do not use migration entries.
+ */
+static void remove_file_migration_ptes(struct page *old, struct page *new)
+{
+ struct vm_area_struct *vma;
+ struct address_space *mapping = page_mapping(new);
+ struct prio_tree_iter iter;
+ pgoff_t pgoff = new->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
+
+ if (!mapping)
+ return;
+
+ spin_lock(&mapping->i_mmap_lock);
+
+ vma_prio_tree_foreach(vma, &iter, &mapping->i_mmap, pgoff, pgoff)
+ remove_migration_pte(vma, old, new);
+
+ spin_unlock(&mapping->i_mmap_lock);
+}
+
+/*
* Must hold mmap_sem lock on at least one of the vmas containing
* the page so that the anon_vma cannot vanish.
*/
-static void remove_migration_ptes(struct page *old, struct page *new)
+static void remove_anon_migration_ptes(struct page *old, struct page *new)
{
struct anon_vma *anon_vma;
struct vm_area_struct *vma;
@@ -199,12 +232,23 @@ static void remove_migration_ptes(struct page *old, struct page *new)
spin_lock(&anon_vma->lock);
list_for_each_entry(vma, &anon_vma->head, anon_vma_node)
- remove_migration_pte(vma, page_address_in_vma(new, vma),
- old, new);
+ remove_migration_pte(vma, old, new);
spin_unlock(&anon_vma->lock);
}
+/*
+ * Get rid of all migration entries and replace them by
+ * references to the indicated page.
+ */
+static void remove_migration_ptes(struct page *old, struct page *new)
+{
+ if (PageAnon(new))
+ remove_anon_migration_ptes(old, new);
+ else
+ remove_file_migration_ptes(old, new);
+}
+
/*
* Something used the pte of a page under migration. We need to
* get to the page and wait until migration is finished.
@@ -424,30 +468,59 @@ int buffer_migrate_page(struct address_space *mapping,
}
EXPORT_SYMBOL(buffer_migrate_page);
+/*
+ * Writeback a page to clean the dirty state
+ */
+static int writeout(struct address_space *mapping, struct page *page)
+{
+ struct writeback_control wbc = {
+ .sync_mode = WB_SYNC_NONE,
+ .nr_to_write = 1,
+ .range_start = 0,
+ .range_end = LLONG_MAX,
+ .nonblocking = 1,
+ .for_reclaim = 1
+ };
+ int rc;
+
+ if (!mapping->a_ops->writepage)
+ /* No write method for the address space */
+ return -EINVAL;
+
+ if (!clear_page_dirty_for_io(page))
+ /* Someone else already triggered a write */
+ return -EAGAIN;
+
+ /*
+ * A dirty page may imply that the underlying filesystem has
+ * the page on some queue. So the page must be clean for
+ * migration. Writeout may mean we loose the lock and the
+ * page state is no longer what we checked for earlier.
+ * At this point we know that the migration attempt cannot
+ * be successful.
+ */
+ remove_migration_ptes(page, page);
+
+ rc = mapping->a_ops->writepage(page, &wbc);
+ if (rc < 0)
+ /* I/O Error writing */
+ return -EIO;
+
+ if (rc != AOP_WRITEPAGE_ACTIVATE)
+ /* unlocked. Relock */
+ lock_page(page);
+
+ return -EAGAIN;
+}
+
+/*
+ * Default handling if a filesystem does not provide a migration function.
+ */
static int fallback_migrate_page(struct address_space *mapping,
struct page *newpage, struct page *page)
{
- /*
- * Default handling if a filesystem does not provide
- * a migration function. We can only migrate clean
- * pages so try to write out any dirty pages first.
- */
- if (PageDirty(page)) {
- switch (pageout(page, mapping)) {
- case PAGE_KEEP:
- case PAGE_ACTIVATE:
- return -EAGAIN;
-
- case PAGE_SUCCESS:
- /* Relock since we lost the lock */
- lock_page(page);
- /* Must retry since page state may have changed */
- return -EAGAIN;
-
- case PAGE_CLEAN:
- ; /* try to migrate the page below */
- }
- }
+ if (PageDirty(page))
+ return writeout(mapping, page);
/*
* Buffers may be managed in a filesystem specific way.
diff --git a/mm/rmap.c b/mm/rmap.c
index 05d6d73a692d..882a85826bb2 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -596,6 +596,7 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
spin_unlock(&mmlist_lock);
}
dec_mm_counter(mm, anon_rss);
+#ifdef CONFIG_MIGRATION
} else {
/*
* Store the pfn of the page in a special migration
@@ -604,12 +605,22 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
*/
BUG_ON(!migration);
entry = make_migration_entry(page, pte_write(pteval));
+#endif
}
set_pte_at(mm, address, pte, swp_entry_to_pte(entry));
BUG_ON(pte_file(*pte));
} else
+#ifdef CONFIG_MIGRATION
+ if (migration) {
+ /* Establish migration entry for a file page */
+ swp_entry_t entry;
+ entry = make_migration_entry(page, pte_write(pteval));
+ set_pte_at(mm, address, pte, swp_entry_to_pte(entry));
+ } else
+#endif
dec_mm_counter(mm, file_rss);
+
page_remove_rmap(page);
page_cache_release(page);
diff --git a/mm/vmscan.c b/mm/vmscan.c
index bc5d4f43036c..71a02e295037 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -290,11 +290,23 @@ static void handle_write_error(struct address_space *mapping,
unlock_page(page);
}
+/* possible outcome of pageout() */
+typedef enum {
+ /* failed to write page out, page is locked */
+ PAGE_KEEP,
+ /* move page to the active list, page is locked */
+ PAGE_ACTIVATE,
+ /* page has been sent to the disk successfully, page is unlocked */
+ PAGE_SUCCESS,
+ /* page is clean and locked */
+ PAGE_CLEAN,
+} pageout_t;
+
/*
* pageout is called by shrink_page_list() for each dirty page.
* Calls ->writepage().
*/
-pageout_t pageout(struct page *page, struct address_space *mapping)
+static pageout_t pageout(struct page *page, struct address_space *mapping)
{
/*
* If the page is dirty, only perform writeback if that write