diff options
| -rw-r--r-- | include/linux/fs.h | 6 | ||||
| -rw-r--r-- | include/linux/migrate.h | 6 | ||||
| -rw-r--r-- | mm/migrate.c | 70 |
3 files changed, 42 insertions, 40 deletions
diff --git a/include/linux/fs.h b/include/linux/fs.h index c823a3815e2..e917403f4d5 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -376,7 +376,8 @@ struct address_space_operations { struct page* (*get_xip_page)(struct address_space *, sector_t, int); /* migrate the contents of a page to the specified target */ - int (*migratepage) (struct page *, struct page *); + int (*migratepage) (struct address_space *, + struct page *, struct page *); }; struct backing_dev_info; @@ -1772,7 +1773,8 @@ extern void simple_release_fs(struct vfsmount **mount, int *count); extern ssize_t simple_read_from_buffer(void __user *, size_t, loff_t *, const void *, size_t); #ifdef CONFIG_MIGRATION -extern int buffer_migrate_page(struct page *, struct page *); +extern int buffer_migrate_page(struct address_space *, + struct page *, struct page *); #else #define buffer_migrate_page NULL #endif diff --git a/include/linux/migrate.h b/include/linux/migrate.h index e8d3b08cc35..287c47b5e5d 100644 --- a/include/linux/migrate.h +++ b/include/linux/migrate.h @@ -6,12 +6,14 @@ #ifdef CONFIG_MIGRATION extern int isolate_lru_page(struct page *p, struct list_head *pagelist); extern int putback_lru_pages(struct list_head *l); -extern int migrate_page(struct page *, struct page *); +extern int migrate_page(struct address_space *, + struct page *, struct page *); extern int migrate_pages(struct list_head *l, struct list_head *t, struct list_head *moved, struct list_head *failed); extern int migrate_pages_to(struct list_head *pagelist, struct vm_area_struct *vma, int dest); -extern int fail_migrate_page(struct page *, struct page *); +extern int fail_migrate_page(struct address_space *, + struct page *, struct page *); extern int migrate_prep(void); diff --git a/mm/migrate.c b/mm/migrate.c index 8095c607a49..f65e69d9452 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -173,15 +173,11 @@ retry: * 2 for pages with a mapping * 3 for pages with a mapping and PagePrivate set. */ -static int migrate_page_move_mapping(struct page *newpage, - struct page *page) +static int migrate_page_move_mapping(struct address_space *mapping, + struct page *newpage, struct page *page) { - struct address_space *mapping = page_mapping(page); struct page **radix_pointer; - if (!mapping) - return -EAGAIN; - write_lock_irq(&mapping->tree_lock); radix_pointer = (struct page **)radix_tree_lookup_slot( @@ -197,15 +193,8 @@ static int migrate_page_move_mapping(struct page *newpage, /* * Now we know that no one else is looking at the page. - * - * Certain minimal information about a page must be available - * in order for other subsystems to properly handle the page if they - * find it through the radix tree update before we are finished - * copying the page. */ get_page(newpage); - newpage->index = page->index; - newpage->mapping = page->mapping; if (PageSwapCache(page)) { SetPageSwapCache(newpage); set_page_private(newpage, page_private(page)); @@ -262,7 +251,8 @@ static void migrate_page_copy(struct page *newpage, struct page *page) ***********************************************************/ /* Always fail migration. Used for mappings that are not movable */ -int fail_migrate_page(struct page *newpage, struct page *page) +int fail_migrate_page(struct address_space *mapping, + struct page *newpage, struct page *page) { return -EIO; } @@ -274,13 +264,14 @@ EXPORT_SYMBOL(fail_migrate_page); * * Pages are locked upon entry and exit. */ -int migrate_page(struct page *newpage, struct page *page) +int migrate_page(struct address_space *mapping, + struct page *newpage, struct page *page) { int rc; BUG_ON(PageWriteback(page)); /* Writeback must be complete */ - rc = migrate_page_move_mapping(newpage, page); + rc = migrate_page_move_mapping(mapping, newpage, page); if (rc) return rc; @@ -305,21 +296,18 @@ EXPORT_SYMBOL(migrate_page); * if the underlying filesystem guarantees that no other references to "page" * exist. */ -int buffer_migrate_page(struct page *newpage, struct page *page) +int buffer_migrate_page(struct address_space *mapping, + struct page *newpage, struct page *page) { - struct address_space *mapping = page->mapping; struct buffer_head *bh, *head; int rc; - if (!mapping) - return -EAGAIN; - if (!page_has_buffers(page)) - return migrate_page(newpage, page); + return migrate_page(mapping, newpage, page); head = page_buffers(page); - rc = migrate_page_move_mapping(newpage, page); + rc = migrate_page_move_mapping(mapping, newpage, page); if (rc) return rc; @@ -448,9 +436,6 @@ redo: goto next; } - newpage = lru_to_page(to); - lock_page(newpage); - /* * Establish swap ptes for anonymous pages or destroy pte * maps for files. @@ -473,11 +458,18 @@ redo: rc = -EPERM; if (try_to_unmap(page, 1) == SWAP_FAIL) /* A vma has VM_LOCKED set -> permanent failure */ - goto unlock_both; + goto unlock_page; rc = -EAGAIN; if (page_mapped(page)) - goto unlock_both; + goto unlock_page; + + newpage = lru_to_page(to); + lock_page(newpage); + /* Prepare mapping for the new page.*/ + newpage->index = page->index; + newpage->mapping = page->mapping; + /* * Pages are properly locked and writeback is complete. * Try to migrate the page. @@ -494,7 +486,8 @@ redo: * own migration function. This is the most common * path for page migration. */ - rc = mapping->a_ops->migratepage(newpage, page); + rc = mapping->a_ops->migratepage(mapping, + newpage, page); goto unlock_both; } @@ -524,7 +517,7 @@ redo: */ if (!page_has_buffers(page) || try_to_release_page(page, GFP_KERNEL)) { - rc = migrate_page(newpage, page); + rc = migrate_page(mapping, newpage, page); goto unlock_both; } @@ -553,12 +546,17 @@ unlock_page: unlock_page(page); next: - if (rc == -EAGAIN) { - retry++; - } else if (rc) { - /* Permanent failure */ - list_move(&page->lru, failed); - nr_failed++; + if (rc) { + if (newpage) + newpage->mapping = NULL; + + if (rc == -EAGAIN) + retry++; + else { + /* Permanent failure */ + list_move(&page->lru, failed); + nr_failed++; + } } else { if (newpage) { /* Successful migration. Return page to LRU */ |