diff --git a/include/linux/migrate.h b/include/linux/migrate.h
index 84a31ad0b791180215809f06bc70b4396a8ed46d..a2901c41466433072aa68ee269ae54ab4adc0f2d 100644
--- a/include/linux/migrate.h
+++ b/include/linux/migrate.h
@@ -5,7 +5,9 @@
#include <linux/mempolicy.h>
#include <linux/migrate_mode.h>
-typedef struct page *new_page_t(struct page *, unsigned long private, int **);
+typedef struct page *new_page_t(struct page *page, unsigned long private,
+ int **reason);
+typedef void free_page_t(struct page *page, unsigned long private);
/*
* Return values from addresss_space_operations.migratepage():
@@ -38,7 +40,7 @@ enum migrate_reason {
extern void putback_movable_pages(struct list_head *l);
extern int migrate_page(struct address_space *,
struct page *, struct page *, enum migrate_mode);
-extern int migrate_pages(struct list_head *l, new_page_t x,
+extern int migrate_pages(struct list_head *l, new_page_t new, free_page_t free,
unsigned long private, enum migrate_mode mode, int reason);
extern int migrate_prep(void);
@@ -56,8 +58,9 @@ extern int migrate_page_move_mapping(struct address_space *mapping,
#else
static inline void putback_movable_pages(struct list_head *l) {}
-static inline int migrate_pages(struct list_head *l, new_page_t x,
- unsigned long private, enum migrate_mode mode, int reason)
+static inline int migrate_pages(struct list_head *l, new_page_t new,
+ free_page_t free, unsigned long private, enum migrate_mode mode,
+ int reason)
{ return -ENOSYS; }
static inline int migrate_prep(void) { return -ENOSYS; }
diff --git a/mm/compaction.c b/mm/compaction.c
index 6010aabde28c987f5ef39e331dc03e68890722e6..f74a362d2e289de88f6d7202318c44697fa424ca 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -1016,7 +1016,7 @@ static int compact_zone(struct zone *zone, struct compact_control *cc)
}
nr_migrate = cc->nr_migratepages;
- err = migrate_pages(&cc->migratepages, compaction_alloc,
+ err = migrate_pages(&cc->migratepages, compaction_alloc, NULL,
(unsigned long)cc,
cc->sync ? MIGRATE_SYNC_LIGHT : MIGRATE_ASYNC,
MR_COMPACTION);
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index d50f17fb9be2c2998c275a8b807316833513cb43..3cd1b652821c4860cf88fd6ff89c7ee3ab26a063 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -1503,7 +1503,7 @@ static int soft_offline_huge_page(struct page *page, int flags)
/* Keep page count to indicate a given hugepage is isolated. */
list_move(&hpage->lru, &pagelist);
- ret = migrate_pages(&pagelist, new_page, MPOL_MF_MOVE_ALL,
+ ret = migrate_pages(&pagelist, new_page, NULL, MPOL_MF_MOVE_ALL,
MIGRATE_SYNC, MR_MEMORY_FAILURE);
if (ret) {
pr_info("soft offline: %#lx: migration failed %d, type %lx\n",
@@ -1584,7 +1584,7 @@ static int __soft_offline_page(struct page *page, int flags)
inc_zone_page_state(page, NR_ISOLATED_ANON +
page_is_file_cache(page));
list_add(&page->lru, &pagelist);
- ret = migrate_pages(&pagelist, new_page, MPOL_MF_MOVE_ALL,
+ ret = migrate_pages(&pagelist, new_page, NULL, MPOL_MF_MOVE_ALL,
MIGRATE_SYNC, MR_MEMORY_FAILURE);
if (ret) {
if (!list_empty(&pagelist)) {
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index cbb7ca0ac44ba2780500c0e5582bde3c5ed54c03..469bbf505f85543f7184428016b56964144e400d 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -1394,7 +1394,7 @@ do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
* alloc_migrate_target should be improooooved!!
* migrate_pages returns # of failed pages.
*/
- ret = migrate_pages(&source, alloc_migrate_target, 0,
+ ret = migrate_pages(&source, alloc_migrate_target, NULL, 0,
MIGRATE_SYNC, MR_MEMORY_HOTPLUG);
if (ret)
putback_movable_pages(&source);
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 7f7864b95e8edadc0cbe7f7e50fbd254512a2b77..16bc9fa42998805f43fce4853b92d06d63ff963d 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -1028,7 +1028,7 @@ static int migrate_to_node(struct mm_struct *mm, int source, int dest,
flags | MPOL_MF_DISCONTIG_OK, &pagelist);
if (!list_empty(&pagelist)) {
- err = migrate_pages(&pagelist, new_node_page, dest,
+ err = migrate_pages(&pagelist, new_node_page, NULL, dest,
MIGRATE_SYNC, MR_SYSCALL);
if (err)
putback_movable_pages(&pagelist);
@@ -1277,7 +1277,7 @@ static long do_mbind(unsigned long start, unsigned long len,
if (!list_empty(&pagelist)) {
WARN_ON_ONCE(flags & MPOL_MF_LAZY);
nr_failed = migrate_pages(&pagelist, new_vma_page,
- (unsigned long)vma,
+ NULL, (unsigned long)vma,
MIGRATE_SYNC, MR_MEMPOLICY_MBIND);
if (nr_failed)
putback_movable_pages(&pagelist);
diff --git a/mm/migrate.c b/mm/migrate.c
index 6247be7fa30ed387464e4be1a36311e5e7ea742a..2a459675eeaba4af57a5a38dfc891049f3f93394 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -938,8 +938,9 @@ static int __unmap_and_move(struct page *page, struct page *newpage,
* Obtain the lock on page, remove all ptes and migrate the page
* to the newly allocated page in newpage.
*/
-static int unmap_and_move(new_page_t get_new_page, unsigned long private,
- struct page *page, int force, enum migrate_mode mode)
+static int unmap_and_move(new_page_t get_new_page, free_page_t put_new_page,
+ unsigned long private, struct page *page, int force,
+ enum migrate_mode mode)
{
int rc = 0;
int *result = NULL;
@@ -983,11 +984,17 @@ static int unmap_and_move(new_page_t get_new_page, unsigned long private,
page_is_file_cache(page));
putback_lru_page(page);
}
+
/*
- * Move the new page to the LRU. If migration was not successful
- * then this will free the page.
+ * If migration was not successful and there's a freeing callback, use
+ * it. Otherwise, putback_lru_page() will drop the reference grabbed
+ * during isolation.
*/
- putback_lru_page(newpage);
+ if (rc != MIGRATEPAGE_SUCCESS && put_new_page)
+ put_new_page(newpage, private);
+ else
+ putback_lru_page(newpage);
+
if (result) {
if (rc)
*result = rc;
@@ -1016,8 +1023,9 @@ static int unmap_and_move(new_page_t get_new_page, unsigned long private,
* will wait in the page fault for migration to complete.
*/
static int unmap_and_move_huge_page(new_page_t get_new_page,
- unsigned long private, struct page *hpage,
- int force, enum migrate_mode mode)
+ free_page_t put_new_page, unsigned long private,
+ struct page *hpage, int force,
+ enum migrate_mode mode)
{
int rc = 0;
int *result = NULL;
@@ -1056,20 +1064,30 @@ static int unmap_and_move_huge_page(new_page_t get_new_page,
if (!page_mapped(hpage))
rc = move_to_new_page(new_hpage, hpage, 1, mode);
- if (rc)
+ if (rc != MIGRATEPAGE_SUCCESS)
remove_migration_ptes(hpage, hpage);
if (anon_vma)
put_anon_vma(anon_vma);
- if (!rc)
+ if (rc == MIGRATEPAGE_SUCCESS)
hugetlb_cgroup_migrate(hpage, new_hpage);
unlock_page(hpage);
out:
if (rc != -EAGAIN)
putback_active_hugepage(hpage);
- put_page(new_hpage);
+
+ /*
+ * If migration was not successful and there's a freeing callback, use
+ * it. Otherwise, put_page() will drop the reference grabbed during
+ * isolation.
+ */
+ if (rc != MIGRATEPAGE_SUCCESS && put_new_page)
+ put_new_page(new_hpage, private);
+ else
+ put_page(new_hpage);
+
if (result) {
if (rc)
*result = rc;
@@ -1086,6 +1104,8 @@ static int unmap_and_move_huge_page(new_page_t get_new_page,
* @from: The list of pages to be migrated.
* @get_new_page: The function used to allocate free pages to be used
* as the target of the page migration.
+ * @put_new_page: The function used to free target pages if migration
+ * fails, or NULL if no special handling is necessary.
* @private: Private data to be passed on to get_new_page()
* @mode: The migration mode that specifies the constraints for
* page migration, if any.
@@ -1099,7 +1119,8 @@ static int unmap_and_move_huge_page(new_page_t get_new_page,
* Returns the number of pages that were not migrated, or an error code.
*/
int migrate_pages(struct list_head *from, new_page_t get_new_page,
- unsigned long private, enum migrate_mode mode, int reason)
+ free_page_t put_new_page, unsigned long private,
+ enum migrate_mode mode, int reason)
{
int retry = 1;
int nr_failed = 0;
@@ -1121,10 +1142,11 @@ int migrate_pages(struct list_head *from, new_page_t get_new_page,
if (PageHuge(page))
rc = unmap_and_move_huge_page(get_new_page,
- private, page, pass > 2, mode);
+ put_new_page, private, page,
+ pass > 2, mode);
else
- rc = unmap_and_move(get_new_page, private,
- page, pass > 2, mode);
+ rc = unmap_and_move(get_new_page, put_new_page,
+ private, page, pass > 2, mode);
switch(rc) {
case -ENOMEM:
@@ -1273,7 +1295,7 @@ static int do_move_page_to_node_array(struct mm_struct *mm,
err = 0;
if (!list_empty(&pagelist)) {
- err = migrate_pages(&pagelist, new_page_node,
+ err = migrate_pages(&pagelist, new_page_node, NULL,
(unsigned long)pm, MIGRATE_SYNC, MR_SYSCALL);
if (err)
putback_movable_pages(&pagelist);
@@ -1729,7 +1751,8 @@ int migrate_misplaced_page(struct page *page, struct vm_area_struct *vma,
list_add(&page->lru, &migratepages);
nr_remaining = migrate_pages(&migratepages, alloc_misplaced_dst_page,
- node, MIGRATE_ASYNC, MR_NUMA_MISPLACED);
+ NULL, node, MIGRATE_ASYNC,
+ MR_NUMA_MISPLACED);
if (nr_remaining) {
if (!list_empty(&migratepages)) {
list_del(&page->lru);
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 132c337dbe55d5ce4807740007c05b809ffe3808..027d0294413a9af8158a1b78df1ff4d585590674 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -6218,7 +6218,7 @@ static int __alloc_contig_migrate_range(struct compact_control *cc,
cc->nr_migratepages -= nr_reclaimed;
ret = migrate_pages(&cc->migratepages, alloc_migrate_target,
- 0, MIGRATE_SYNC, MR_CMA);
+ NULL, 0, MIGRATE_SYNC, MR_CMA);
}
if (ret < 0) {
putback_movable_pages(&cc->migratepages);