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-rw-r--r--mm/migrate.c274
1 files changed, 139 insertions, 135 deletions
diff --git a/mm/migrate.c b/mm/migrate.c
index 2a80136b23bb..6602941bfab0 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -37,36 +37,6 @@
#define lru_to_page(_head) (list_entry((_head)->prev, struct page, lru))
/*
- * Isolate one page from the LRU lists. If successful put it onto
- * the indicated list with elevated page count.
- *
- * Result:
- * -EBUSY: page not on LRU list
- * 0: page removed from LRU list and added to the specified list.
- */
-int isolate_lru_page(struct page *page, struct list_head *pagelist)
-{
- int ret = -EBUSY;
-
- if (PageLRU(page)) {
- struct zone *zone = page_zone(page);
-
- spin_lock_irq(&zone->lru_lock);
- if (PageLRU(page) && get_page_unless_zero(page)) {
- ret = 0;
- ClearPageLRU(page);
- if (PageActive(page))
- del_page_from_active_list(zone, page);
- else
- del_page_from_inactive_list(zone, page);
- list_add_tail(&page->lru, pagelist);
- }
- spin_unlock_irq(&zone->lru_lock);
- }
- return ret;
-}
-
-/*
* migrate_prep() needs to be called before we start compiling a list of pages
* to be migrated using isolate_lru_page().
*/
@@ -83,23 +53,9 @@ int migrate_prep(void)
return 0;
}
-static inline void move_to_lru(struct page *page)
-{
- if (PageActive(page)) {
- /*
- * lru_cache_add_active checks that
- * the PG_active bit is off.
- */
- ClearPageActive(page);
- lru_cache_add_active(page);
- } else {
- lru_cache_add(page);
- }
- put_page(page);
-}
-
/*
- * Add isolated pages on the list back to the LRU.
+ * Add isolated pages on the list back to the LRU under page lock
+ * to avoid leaking evictable pages back onto unevictable list.
*
* returns the number of pages put back.
*/
@@ -111,7 +67,7 @@ int putback_lru_pages(struct list_head *l)
list_for_each_entry_safe(page, page2, l, lru) {
list_del(&page->lru);
- move_to_lru(page);
+ putback_lru_page(page);
count++;
}
return count;
@@ -374,8 +330,6 @@ static int migrate_page_move_mapping(struct address_space *mapping,
__inc_zone_page_state(newpage, NR_FILE_PAGES);
spin_unlock_irq(&mapping->tree_lock);
- if (!PageSwapCache(newpage))
- mem_cgroup_uncharge_cache_page(page);
return 0;
}
@@ -385,6 +339,8 @@ static int migrate_page_move_mapping(struct address_space *mapping,
*/
static void migrate_page_copy(struct page *newpage, struct page *page)
{
+ int anon;
+
copy_highpage(newpage, page);
if (PageError(page))
@@ -393,8 +349,11 @@ static void migrate_page_copy(struct page *newpage, struct page *page)
SetPageReferenced(newpage);
if (PageUptodate(page))
SetPageUptodate(newpage);
- if (PageActive(page))
+ if (TestClearPageActive(page)) {
+ VM_BUG_ON(PageUnevictable(page));
SetPageActive(newpage);
+ } else
+ unevictable_migrate_page(newpage, page);
if (PageChecked(page))
SetPageChecked(newpage);
if (PageMappedToDisk(page))
@@ -412,14 +371,20 @@ static void migrate_page_copy(struct page *newpage, struct page *page)
__set_page_dirty_nobuffers(newpage);
}
+ mlock_migrate_page(newpage, page);
+
#ifdef CONFIG_SWAP
ClearPageSwapCache(page);
#endif
- ClearPageActive(page);
ClearPagePrivate(page);
set_page_private(page, 0);
+ /* page->mapping contains a flag for PageAnon() */
+ anon = PageAnon(page);
page->mapping = NULL;
+ if (!anon) /* This page was removed from radix-tree. */
+ mem_cgroup_uncharge_cache_page(page);
+
/*
* If any waiters have accumulated on the new page then
* wake them up.
@@ -594,6 +559,10 @@ static int fallback_migrate_page(struct address_space *mapping,
*
* The new page will have replaced the old page if this function
* is successful.
+ *
+ * Return value:
+ * < 0 - error code
+ * == 0 - success
*/
static int move_to_new_page(struct page *newpage, struct page *page)
{
@@ -611,6 +580,8 @@ static int move_to_new_page(struct page *newpage, struct page *page)
/* Prepare mapping for the new page.*/
newpage->index = page->index;
newpage->mapping = page->mapping;
+ if (PageSwapBacked(page))
+ SetPageSwapBacked(newpage);
mapping = page_mapping(page);
if (!mapping)
@@ -654,9 +625,10 @@ static int unmap_and_move(new_page_t get_new_page, unsigned long private,
if (!newpage)
return -ENOMEM;
- if (page_count(page) == 1)
+ if (page_count(page) == 1) {
/* page was freed from under us. So we are done. */
goto move_newpage;
+ }
charge = mem_cgroup_prepare_migration(page, newpage);
if (charge == -ENOMEM) {
@@ -730,7 +702,6 @@ rcu_unlock:
rcu_read_unlock();
unlock:
-
unlock_page(page);
if (rc != -EAGAIN) {
@@ -741,17 +712,19 @@ unlock:
* restored.
*/
list_del(&page->lru);
- move_to_lru(page);
+ putback_lru_page(page);
}
move_newpage:
if (!charge)
mem_cgroup_end_migration(newpage);
+
/*
* Move the new page to the LRU. If migration was not successful
* then this will free the page.
*/
- move_to_lru(newpage);
+ putback_lru_page(newpage);
+
if (result) {
if (rc)
*result = rc;
@@ -858,9 +831,11 @@ static struct page *new_page_node(struct page *p, unsigned long private,
* Move a set of pages as indicated in the pm array. The addr
* field must be set to the virtual address of the page to be moved
* and the node number must contain a valid target node.
+ * The pm array ends with node = MAX_NUMNODES.
*/
-static int do_move_pages(struct mm_struct *mm, struct page_to_node *pm,
- int migrate_all)
+static int do_move_page_to_node_array(struct mm_struct *mm,
+ struct page_to_node *pm,
+ int migrate_all)
{
int err;
struct page_to_node *pp;
@@ -914,7 +889,9 @@ static int do_move_pages(struct mm_struct *mm, struct page_to_node *pm,
!migrate_all)
goto put_and_set;
- err = isolate_lru_page(page, &pagelist);
+ err = isolate_lru_page(page);
+ if (!err)
+ list_add_tail(&page->lru, &pagelist);
put_and_set:
/*
* Either remove the duplicate refcount from
@@ -926,36 +903,118 @@ set_status:
pp->status = err;
}
+ err = 0;
if (!list_empty(&pagelist))
err = migrate_pages(&pagelist, new_page_node,
(unsigned long)pm);
- else
- err = -ENOENT;
up_read(&mm->mmap_sem);
return err;
}
/*
- * Determine the nodes of a list of pages. The addr in the pm array
- * must have been set to the virtual address of which we want to determine
- * the node number.
+ * Migrate an array of page address onto an array of nodes and fill
+ * the corresponding array of status.
*/
-static int do_pages_stat(struct mm_struct *mm, struct page_to_node *pm)
+static int do_pages_move(struct mm_struct *mm, struct task_struct *task,
+ unsigned long nr_pages,
+ const void __user * __user *pages,
+ const int __user *nodes,
+ int __user *status, int flags)
{
+ struct page_to_node *pm = NULL;
+ nodemask_t task_nodes;
+ int err = 0;
+ int i;
+
+ task_nodes = cpuset_mems_allowed(task);
+
+ /* Limit nr_pages so that the multiplication may not overflow */
+ if (nr_pages >= ULONG_MAX / sizeof(struct page_to_node) - 1) {
+ err = -E2BIG;
+ goto out;
+ }
+
+ pm = vmalloc((nr_pages + 1) * sizeof(struct page_to_node));
+ if (!pm) {
+ err = -ENOMEM;
+ goto out;
+ }
+
+ /*
+ * Get parameters from user space and initialize the pm
+ * array. Return various errors if the user did something wrong.
+ */
+ for (i = 0; i < nr_pages; i++) {
+ const void __user *p;
+
+ err = -EFAULT;
+ if (get_user(p, pages + i))
+ goto out_pm;
+
+ pm[i].addr = (unsigned long)p;
+ if (nodes) {
+ int node;
+
+ if (get_user(node, nodes + i))
+ goto out_pm;
+
+ err = -ENODEV;
+ if (!node_state(node, N_HIGH_MEMORY))
+ goto out_pm;
+
+ err = -EACCES;
+ if (!node_isset(node, task_nodes))
+ goto out_pm;
+
+ pm[i].node = node;
+ } else
+ pm[i].node = 0; /* anything to not match MAX_NUMNODES */
+ }
+ /* End marker */
+ pm[nr_pages].node = MAX_NUMNODES;
+
+ err = do_move_page_to_node_array(mm, pm, flags & MPOL_MF_MOVE_ALL);
+ if (err >= 0)
+ /* Return status information */
+ for (i = 0; i < nr_pages; i++)
+ if (put_user(pm[i].status, status + i))
+ err = -EFAULT;
+
+out_pm:
+ vfree(pm);
+out:
+ return err;
+}
+
+/*
+ * Determine the nodes of an array of pages and store it in an array of status.
+ */
+static int do_pages_stat(struct mm_struct *mm, unsigned long nr_pages,
+ const void __user * __user *pages,
+ int __user *status)
+{
+ unsigned long i;
+ int err;
+
down_read(&mm->mmap_sem);
- for ( ; pm->node != MAX_NUMNODES; pm++) {
+ for (i = 0; i < nr_pages; i++) {
+ const void __user *p;
+ unsigned long addr;
struct vm_area_struct *vma;
struct page *page;
- int err;
err = -EFAULT;
- vma = find_vma(mm, pm->addr);
+ if (get_user(p, pages+i))
+ goto out;
+ addr = (unsigned long) p;
+
+ vma = find_vma(mm, addr);
if (!vma)
goto set_status;
- page = follow_page(vma, pm->addr, 0);
+ page = follow_page(vma, addr, 0);
err = PTR_ERR(page);
if (IS_ERR(page))
@@ -968,11 +1027,13 @@ static int do_pages_stat(struct mm_struct *mm, struct page_to_node *pm)
err = page_to_nid(page);
set_status:
- pm->status = err;
+ put_user(err, status+i);
}
+ err = 0;
+out:
up_read(&mm->mmap_sem);
- return 0;
+ return err;
}
/*
@@ -984,12 +1045,9 @@ asmlinkage long sys_move_pages(pid_t pid, unsigned long nr_pages,
const int __user *nodes,
int __user *status, int flags)
{
- int err = 0;
- int i;
struct task_struct *task;
- nodemask_t task_nodes;
struct mm_struct *mm;
- struct page_to_node *pm = NULL;
+ int err;
/* Check flags */
if (flags & ~(MPOL_MF_MOVE|MPOL_MF_MOVE_ALL))
@@ -1021,75 +1079,21 @@ asmlinkage long sys_move_pages(pid_t pid, unsigned long nr_pages,
(current->uid != task->suid) && (current->uid != task->uid) &&
!capable(CAP_SYS_NICE)) {
err = -EPERM;
- goto out2;
+ goto out;
}
err = security_task_movememory(task);
if (err)
- goto out2;
-
-
- task_nodes = cpuset_mems_allowed(task);
-
- /* Limit nr_pages so that the multiplication may not overflow */
- if (nr_pages >= ULONG_MAX / sizeof(struct page_to_node) - 1) {
- err = -E2BIG;
- goto out2;
- }
-
- pm = vmalloc((nr_pages + 1) * sizeof(struct page_to_node));
- if (!pm) {
- err = -ENOMEM;
- goto out2;
- }
-
- /*
- * Get parameters from user space and initialize the pm
- * array. Return various errors if the user did something wrong.
- */
- for (i = 0; i < nr_pages; i++) {
- const void __user *p;
-
- err = -EFAULT;
- if (get_user(p, pages + i))
- goto out;
-
- pm[i].addr = (unsigned long)p;
- if (nodes) {
- int node;
-
- if (get_user(node, nodes + i))
- goto out;
-
- err = -ENODEV;
- if (!node_state(node, N_HIGH_MEMORY))
- goto out;
-
- err = -EACCES;
- if (!node_isset(node, task_nodes))
- goto out;
+ goto out;
- pm[i].node = node;
- } else
- pm[i].node = 0; /* anything to not match MAX_NUMNODES */
+ if (nodes) {
+ err = do_pages_move(mm, task, nr_pages, pages, nodes, status,
+ flags);
+ } else {
+ err = do_pages_stat(mm, nr_pages, pages, status);
}
- /* End marker */
- pm[nr_pages].node = MAX_NUMNODES;
-
- if (nodes)
- err = do_move_pages(mm, pm, flags & MPOL_MF_MOVE_ALL);
- else
- err = do_pages_stat(mm, pm);
-
- if (err >= 0)
- /* Return status information */
- for (i = 0; i < nr_pages; i++)
- if (put_user(pm[i].status, status + i))
- err = -EFAULT;
out:
- vfree(pm);
-out2:
mmput(mm);
return err;
}