From 68f2736a858324c3ec852f6c2cddd9d1c777357d Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Tue, 7 Jun 2022 15:38:48 -0400 Subject: mm: Convert all PageMovable users to movable_operations These drivers are rather uncomfortably hammered into the address_space_operations hole. They aren't filesystems and don't behave like filesystems. They just need their own movable_operations structure, which we can point to directly from page->mapping. Signed-off-by: Matthew Wilcox (Oracle) --- mm/balloon_compaction.c | 10 ++--- mm/compaction.c | 29 ++++++-------- mm/migrate.c | 24 ++++++------ mm/util.c | 4 +- mm/z3fold.c | 84 +++++---------------------------------- mm/zsmalloc.c | 102 +++++++++++------------------------------------- 6 files changed, 62 insertions(+), 191 deletions(-) (limited to 'mm') diff --git a/mm/balloon_compaction.c b/mm/balloon_compaction.c index 4b8eab4b3f45..22c96fed70b5 100644 --- a/mm/balloon_compaction.c +++ b/mm/balloon_compaction.c @@ -228,10 +228,8 @@ static void balloon_page_putback(struct page *page) spin_unlock_irqrestore(&b_dev_info->pages_lock, flags); } - /* move_to_new_page() counterpart for a ballooned page */ -static int balloon_page_migrate(struct address_space *mapping, - struct page *newpage, struct page *page, +static int balloon_page_migrate(struct page *newpage, struct page *page, enum migrate_mode mode) { struct balloon_dev_info *balloon = balloon_page_device(page); @@ -250,11 +248,11 @@ static int balloon_page_migrate(struct address_space *mapping, return balloon->migratepage(balloon, newpage, page, mode); } -const struct address_space_operations balloon_aops = { - .migratepage = balloon_page_migrate, +const struct movable_operations balloon_mops = { + .migrate_page = balloon_page_migrate, .isolate_page = balloon_page_isolate, .putback_page = balloon_page_putback, }; -EXPORT_SYMBOL_GPL(balloon_aops); +EXPORT_SYMBOL_GPL(balloon_mops); #endif /* CONFIG_BALLOON_COMPACTION */ diff --git a/mm/compaction.c b/mm/compaction.c index 1f89b969c12b..f23efba1d118 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -110,28 +110,27 @@ static void split_map_pages(struct list_head *list) } #ifdef CONFIG_COMPACTION - -int PageMovable(struct page *page) +bool PageMovable(struct page *page) { - struct address_space *mapping; + const struct movable_operations *mops; VM_BUG_ON_PAGE(!PageLocked(page), page); if (!__PageMovable(page)) - return 0; + return false; - mapping = page_mapping(page); - if (mapping && mapping->a_ops && mapping->a_ops->isolate_page) - return 1; + mops = page_movable_ops(page); + if (mops) + return true; - return 0; + return false; } EXPORT_SYMBOL(PageMovable); -void __SetPageMovable(struct page *page, struct address_space *mapping) +void __SetPageMovable(struct page *page, const struct movable_operations *mops) { VM_BUG_ON_PAGE(!PageLocked(page), page); - VM_BUG_ON_PAGE((unsigned long)mapping & PAGE_MAPPING_MOVABLE, page); - page->mapping = (void *)((unsigned long)mapping | PAGE_MAPPING_MOVABLE); + VM_BUG_ON_PAGE((unsigned long)mops & PAGE_MAPPING_MOVABLE, page); + page->mapping = (void *)((unsigned long)mops | PAGE_MAPPING_MOVABLE); } EXPORT_SYMBOL(__SetPageMovable); @@ -139,12 +138,10 @@ void __ClearPageMovable(struct page *page) { VM_BUG_ON_PAGE(!PageMovable(page), page); /* - * Clear registered address_space val with keeping PAGE_MAPPING_MOVABLE - * flag so that VM can catch up released page by driver after isolation. - * With it, VM migration doesn't try to put it back. + * This page still has the type of a movable page, but it's + * actually not movable any more. */ - page->mapping = (void *)((unsigned long)page->mapping & - PAGE_MAPPING_MOVABLE); + page->mapping = (void *)PAGE_MAPPING_MOVABLE; } EXPORT_SYMBOL(__ClearPageMovable); diff --git a/mm/migrate.c b/mm/migrate.c index 6c1ea61f39d8..491f03747832 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -59,7 +59,7 @@ int isolate_movable_page(struct page *page, isolate_mode_t mode) { - struct address_space *mapping; + const struct movable_operations *mops; /* * Avoid burning cycles with pages that are yet under __free_pages(), @@ -97,10 +97,10 @@ int isolate_movable_page(struct page *page, isolate_mode_t mode) if (!PageMovable(page) || PageIsolated(page)) goto out_no_isolated; - mapping = page_mapping(page); - VM_BUG_ON_PAGE(!mapping, page); + mops = page_movable_ops(page); + VM_BUG_ON_PAGE(!mops, page); - if (!mapping->a_ops->isolate_page(page, mode)) + if (!mops->isolate_page(page, mode)) goto out_no_isolated; /* Driver shouldn't use PG_isolated bit of page->flags */ @@ -120,10 +120,9 @@ out: static void putback_movable_page(struct page *page) { - struct address_space *mapping; + const struct movable_operations *mops = page_movable_ops(page); - mapping = page_mapping(page); - mapping->a_ops->putback_page(page); + mops->putback_page(page); ClearPageIsolated(page); } @@ -846,16 +845,15 @@ static int fallback_migrate_page(struct address_space *mapping, static int move_to_new_folio(struct folio *dst, struct folio *src, enum migrate_mode mode) { - struct address_space *mapping; int rc = -EAGAIN; bool is_lru = !__PageMovable(&src->page); VM_BUG_ON_FOLIO(!folio_test_locked(src), src); VM_BUG_ON_FOLIO(!folio_test_locked(dst), dst); - mapping = folio_mapping(src); - if (likely(is_lru)) { + struct address_space *mapping = folio_mapping(src); + if (!mapping) rc = migrate_page(mapping, &dst->page, &src->page, mode); else if (mapping->a_ops->migratepage) @@ -872,6 +870,8 @@ static int move_to_new_folio(struct folio *dst, struct folio *src, rc = fallback_migrate_page(mapping, &dst->page, &src->page, mode); } else { + const struct movable_operations *mops; + /* * In case of non-lru page, it could be released after * isolation step. In that case, we shouldn't try migration. @@ -883,8 +883,8 @@ static int move_to_new_folio(struct folio *dst, struct folio *src, goto out; } - rc = mapping->a_ops->migratepage(mapping, &dst->page, - &src->page, mode); + mops = page_movable_ops(&src->page); + rc = mops->migrate_page(&dst->page, &src->page, mode); WARN_ON_ONCE(rc == MIGRATEPAGE_SUCCESS && !folio_test_isolated(src)); } diff --git a/mm/util.c b/mm/util.c index 0837570c9225..53af0e79d3e4 100644 --- a/mm/util.c +++ b/mm/util.c @@ -804,10 +804,10 @@ struct address_space *folio_mapping(struct folio *folio) return swap_address_space(folio_swap_entry(folio)); mapping = folio->mapping; - if ((unsigned long)mapping & PAGE_MAPPING_ANON) + if ((unsigned long)mapping & PAGE_MAPPING_FLAGS) return NULL; - return (void *)((unsigned long)mapping & ~PAGE_MAPPING_FLAGS); + return mapping; } EXPORT_SYMBOL(folio_mapping); diff --git a/mm/z3fold.c b/mm/z3fold.c index f41f8b0d9e9a..cf71da10d04e 100644 --- a/mm/z3fold.c +++ b/mm/z3fold.c @@ -34,15 +34,11 @@ #include #include #include -#include -#include -#include #include #include #include #include #include -#include #include /* @@ -149,7 +145,6 @@ struct z3fold_header { * @compact_wq: workqueue for page layout background optimization * @release_wq: workqueue for safe page release * @work: work_struct for safe page release - * @inode: inode for z3fold pseudo filesystem * * This structure is allocated at pool creation time and maintains metadata * pertaining to a particular z3fold pool. @@ -169,7 +164,6 @@ struct z3fold_pool { struct workqueue_struct *compact_wq; struct workqueue_struct *release_wq; struct work_struct work; - struct inode *inode; }; /* @@ -334,54 +328,6 @@ static inline void free_handle(unsigned long handle, struct z3fold_header *zhdr) } } -static int z3fold_init_fs_context(struct fs_context *fc) -{ - return init_pseudo(fc, Z3FOLD_MAGIC) ? 0 : -ENOMEM; -} - -static struct file_system_type z3fold_fs = { - .name = "z3fold", - .init_fs_context = z3fold_init_fs_context, - .kill_sb = kill_anon_super, -}; - -static struct vfsmount *z3fold_mnt; -static int __init z3fold_mount(void) -{ - int ret = 0; - - z3fold_mnt = kern_mount(&z3fold_fs); - if (IS_ERR(z3fold_mnt)) - ret = PTR_ERR(z3fold_mnt); - - return ret; -} - -static void z3fold_unmount(void) -{ - kern_unmount(z3fold_mnt); -} - -static const struct address_space_operations z3fold_aops; -static int z3fold_register_migration(struct z3fold_pool *pool) -{ - pool->inode = alloc_anon_inode(z3fold_mnt->mnt_sb); - if (IS_ERR(pool->inode)) { - pool->inode = NULL; - return 1; - } - - pool->inode->i_mapping->private_data = pool; - pool->inode->i_mapping->a_ops = &z3fold_aops; - return 0; -} - -static void z3fold_unregister_migration(struct z3fold_pool *pool) -{ - if (pool->inode) - iput(pool->inode); -} - /* Initializes the z3fold header of a newly allocated z3fold page */ static struct z3fold_header *init_z3fold_page(struct page *page, bool headless, struct z3fold_pool *pool, gfp_t gfp) @@ -1002,14 +948,10 @@ static struct z3fold_pool *z3fold_create_pool(const char *name, gfp_t gfp, pool->release_wq = create_singlethread_workqueue(pool->name); if (!pool->release_wq) goto out_wq; - if (z3fold_register_migration(pool)) - goto out_rwq; INIT_WORK(&pool->work, free_pages_work); pool->ops = ops; return pool; -out_rwq: - destroy_workqueue(pool->release_wq); out_wq: destroy_workqueue(pool->compact_wq); out_unbuddied: @@ -1043,11 +985,12 @@ static void z3fold_destroy_pool(struct z3fold_pool *pool) destroy_workqueue(pool->compact_wq); destroy_workqueue(pool->release_wq); - z3fold_unregister_migration(pool); free_percpu(pool->unbuddied); kfree(pool); } +static const struct movable_operations z3fold_mops; + /** * z3fold_alloc() - allocates a region of a given size * @pool: z3fold pool from which to allocate @@ -1117,11 +1060,11 @@ retry: } if (can_sleep) { lock_page(page); - __SetPageMovable(page, pool->inode->i_mapping); + __SetPageMovable(page, &z3fold_mops); unlock_page(page); } else { WARN_ON(!trylock_page(page)); - __SetPageMovable(page, pool->inode->i_mapping); + __SetPageMovable(page, &z3fold_mops); unlock_page(page); } z3fold_page_lock(zhdr); @@ -1554,12 +1497,11 @@ out: return false; } -static int z3fold_page_migrate(struct address_space *mapping, struct page *newpage, - struct page *page, enum migrate_mode mode) +static int z3fold_page_migrate(struct page *newpage, struct page *page, + enum migrate_mode mode) { struct z3fold_header *zhdr, *new_zhdr; struct z3fold_pool *pool; - struct address_space *new_mapping; VM_BUG_ON_PAGE(!PageMovable(page), page); VM_BUG_ON_PAGE(!PageIsolated(page), page); @@ -1592,7 +1534,6 @@ static int z3fold_page_migrate(struct address_space *mapping, struct page *newpa * so we only have to reinitialize it. */ INIT_LIST_HEAD(&new_zhdr->buddy); - new_mapping = page_mapping(page); __ClearPageMovable(page); get_page(newpage); @@ -1608,7 +1549,7 @@ static int z3fold_page_migrate(struct address_space *mapping, struct page *newpa spin_lock(&pool->lock); list_add(&newpage->lru, &pool->lru); spin_unlock(&pool->lock); - __SetPageMovable(newpage, new_mapping); + __SetPageMovable(newpage, &z3fold_mops); z3fold_page_unlock(new_zhdr); queue_work_on(new_zhdr->cpu, pool->compact_wq, &new_zhdr->work); @@ -1642,9 +1583,9 @@ static void z3fold_page_putback(struct page *page) z3fold_page_unlock(zhdr); } -static const struct address_space_operations z3fold_aops = { +static const struct movable_operations z3fold_mops = { .isolate_page = z3fold_page_isolate, - .migratepage = z3fold_page_migrate, + .migrate_page = z3fold_page_migrate, .putback_page = z3fold_page_putback, }; @@ -1746,17 +1687,11 @@ MODULE_ALIAS("zpool-z3fold"); static int __init init_z3fold(void) { - int ret; - /* * Make sure the z3fold header is not larger than the page size and * there has remaining spaces for its buddy. */ BUILD_BUG_ON(ZHDR_SIZE_ALIGNED > PAGE_SIZE - CHUNK_SIZE); - ret = z3fold_mount(); - if (ret) - return ret; - zpool_register_driver(&z3fold_zpool_driver); return 0; @@ -1764,7 +1699,6 @@ static int __init init_z3fold(void) static void __exit exit_z3fold(void) { - z3fold_unmount(); zpool_unregister_driver(&z3fold_zpool_driver); } diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c index 5d5fc04385b8..71d6edcbea48 100644 --- a/mm/zsmalloc.c +++ b/mm/zsmalloc.c @@ -41,7 +41,6 @@ #include #include #include -#include #include #include #include @@ -59,8 +58,6 @@ #include #include #include -#include -#include #include #include #include @@ -177,10 +174,6 @@ struct zs_size_stat { static struct dentry *zs_stat_root; #endif -#ifdef CONFIG_COMPACTION -static struct vfsmount *zsmalloc_mnt; -#endif - /* * We assign a page to ZS_ALMOST_EMPTY fullness group when: * n <= N / f, where @@ -252,7 +245,6 @@ struct zs_pool { struct dentry *stat_dentry; #endif #ifdef CONFIG_COMPACTION - struct inode *inode; struct work_struct free_work; #endif /* protect page/zspage migration */ @@ -271,6 +263,7 @@ struct zspage { unsigned int freeobj; struct page *first_page; struct list_head list; /* fullness list */ + struct zs_pool *pool; #ifdef CONFIG_COMPACTION rwlock_t lock; #endif @@ -295,8 +288,6 @@ static bool ZsHugePage(struct zspage *zspage) } #ifdef CONFIG_COMPACTION -static int zs_register_migration(struct zs_pool *pool); -static void zs_unregister_migration(struct zs_pool *pool); static void migrate_lock_init(struct zspage *zspage); static void migrate_read_lock(struct zspage *zspage); static void migrate_read_unlock(struct zspage *zspage); @@ -307,10 +298,6 @@ static void kick_deferred_free(struct zs_pool *pool); static void init_deferred_free(struct zs_pool *pool); static void SetZsPageMovable(struct zs_pool *pool, struct zspage *zspage); #else -static int zsmalloc_mount(void) { return 0; } -static void zsmalloc_unmount(void) {} -static int zs_register_migration(struct zs_pool *pool) { return 0; } -static void zs_unregister_migration(struct zs_pool *pool) {} static void migrate_lock_init(struct zspage *zspage) {} static void migrate_read_lock(struct zspage *zspage) {} static void migrate_read_unlock(struct zspage *zspage) {} @@ -1083,6 +1070,7 @@ static struct zspage *alloc_zspage(struct zs_pool *pool, create_page_chain(class, zspage, pages); init_zspage(class, zspage); + zspage->pool = pool; return zspage; } @@ -1754,33 +1742,6 @@ static void lock_zspage(struct zspage *zspage) migrate_read_unlock(zspage); } -static int zs_init_fs_context(struct fs_context *fc) -{ - return init_pseudo(fc, ZSMALLOC_MAGIC) ? 0 : -ENOMEM; -} - -static struct file_system_type zsmalloc_fs = { - .name = "zsmalloc", - .init_fs_context = zs_init_fs_context, - .kill_sb = kill_anon_super, -}; - -static int zsmalloc_mount(void) -{ - int ret = 0; - - zsmalloc_mnt = kern_mount(&zsmalloc_fs); - if (IS_ERR(zsmalloc_mnt)) - ret = PTR_ERR(zsmalloc_mnt); - - return ret; -} - -static void zsmalloc_unmount(void) -{ - kern_unmount(zsmalloc_mnt); -} - static void migrate_lock_init(struct zspage *zspage) { rwlock_init(&zspage->lock); @@ -1823,6 +1784,8 @@ static void dec_zspage_isolation(struct zspage *zspage) zspage->isolated--; } +static const struct movable_operations zsmalloc_mops; + static void replace_sub_page(struct size_class *class, struct zspage *zspage, struct page *newpage, struct page *oldpage) { @@ -1843,7 +1806,7 @@ static void replace_sub_page(struct size_class *class, struct zspage *zspage, set_first_obj_offset(newpage, get_first_obj_offset(oldpage)); if (unlikely(ZsHugePage(zspage))) newpage->index = oldpage->index; - __SetPageMovable(newpage, page_mapping(oldpage)); + __SetPageMovable(newpage, &zsmalloc_mops); } static bool zs_page_isolate(struct page *page, isolate_mode_t mode) @@ -1865,8 +1828,8 @@ static bool zs_page_isolate(struct page *page, isolate_mode_t mode) return true; } -static int zs_page_migrate(struct address_space *mapping, struct page *newpage, - struct page *page, enum migrate_mode mode) +static int zs_page_migrate(struct page *newpage, struct page *page, + enum migrate_mode mode) { struct zs_pool *pool; struct size_class *class; @@ -1889,14 +1852,15 @@ static int zs_page_migrate(struct address_space *mapping, struct page *newpage, VM_BUG_ON_PAGE(!PageMovable(page), page); VM_BUG_ON_PAGE(!PageIsolated(page), page); - pool = mapping->private_data; + /* The page is locked, so this pointer must remain valid */ + zspage = get_zspage(page); + pool = zspage->pool; /* * The pool migrate_lock protects the race between zpage migration * and zs_free. */ write_lock(&pool->migrate_lock); - zspage = get_zspage(page); class = zspage_class(pool, zspage); /* @@ -1964,31 +1928,12 @@ static void zs_page_putback(struct page *page) migrate_write_unlock(zspage); } -static const struct address_space_operations zsmalloc_aops = { +static const struct movable_operations zsmalloc_mops = { .isolate_page = zs_page_isolate, - .migratepage = zs_page_migrate, + .migrate_page = zs_page_migrate, .putback_page = zs_page_putback, }; -static int zs_register_migration(struct zs_pool *pool) -{ - pool->inode = alloc_anon_inode(zsmalloc_mnt->mnt_sb); - if (IS_ERR(pool->inode)) { - pool->inode = NULL; - return 1; - } - - pool->inode->i_mapping->private_data = pool; - pool->inode->i_mapping->a_ops = &zsmalloc_aops; - return 0; -} - -static void zs_unregister_migration(struct zs_pool *pool) -{ - flush_work(&pool->free_work); - iput(pool->inode); -} - /* * Caller should hold page_lock of all pages in the zspage * In here, we cannot use zspage meta data. @@ -2032,6 +1977,11 @@ static void kick_deferred_free(struct zs_pool *pool) schedule_work(&pool->free_work); } +static void zs_flush_migration(struct zs_pool *pool) +{ + flush_work(&pool->free_work); +} + static void init_deferred_free(struct zs_pool *pool) { INIT_WORK(&pool->free_work, async_free_zspage); @@ -2043,10 +1993,12 @@ static void SetZsPageMovable(struct zs_pool *pool, struct zspage *zspage) do { WARN_ON(!trylock_page(page)); - __SetPageMovable(page, pool->inode->i_mapping); + __SetPageMovable(page, &zsmalloc_mops); unlock_page(page); } while ((page = get_next_page(page)) != NULL); } +#else +static inline void zs_flush_migration(struct zs_pool *pool) { } #endif /* @@ -2324,9 +2276,6 @@ struct zs_pool *zs_create_pool(const char *name) /* debug only, don't abort if it fails */ zs_pool_stat_create(pool, name); - if (zs_register_migration(pool)) - goto err; - /* * Not critical since shrinker is only used to trigger internal * defragmentation of the pool which is pretty optional thing. If @@ -2348,7 +2297,7 @@ void zs_destroy_pool(struct zs_pool *pool) int i; zs_unregister_shrinker(pool); - zs_unregister_migration(pool); + zs_flush_migration(pool); zs_pool_stat_destroy(pool); for (i = 0; i < ZS_SIZE_CLASSES; i++) { @@ -2380,14 +2329,10 @@ static int __init zs_init(void) { int ret; - ret = zsmalloc_mount(); - if (ret) - goto out; - ret = cpuhp_setup_state(CPUHP_MM_ZS_PREPARE, "mm/zsmalloc:prepare", zs_cpu_prepare, zs_cpu_dead); if (ret) - goto hp_setup_fail; + goto out; #ifdef CONFIG_ZPOOL zpool_register_driver(&zs_zpool_driver); @@ -2397,8 +2342,6 @@ static int __init zs_init(void) return 0; -hp_setup_fail: - zsmalloc_unmount(); out: return ret; } @@ -2408,7 +2351,6 @@ static void __exit zs_exit(void) #ifdef CONFIG_ZPOOL zpool_unregister_driver(&zs_zpool_driver); #endif - zsmalloc_unmount(); cpuhp_remove_state(CPUHP_MM_ZS_PREPARE); zs_stat_exit(); -- cgit v1.2.3-58-ga151