diff options
| -rw-r--r-- | drivers/virtio/virtio_balloon.c | 60 | ||||
| -rw-r--r-- | include/linux/balloon_compaction.h | 72 | ||||
| -rw-r--r-- | include/linux/pagemap.h | 18 | ||||
| -rw-r--r-- | mm/balloon_compaction.c | 95 |
4 files changed, 39 insertions, 206 deletions
diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c index c3eb93f..2bad7f9 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -59,7 +59,7 @@ struct virtio_balloon * Each page on this list adds VIRTIO_BALLOON_PAGES_PER_PAGE * to num_pages above. */ - struct balloon_dev_info *vb_dev_info; + struct balloon_dev_info vb_dev_info; /* Synchronize access/update to this struct virtio_balloon elements */ struct mutex balloon_lock; @@ -127,7 +127,7 @@ static void set_page_pfns(u32 pfns[], struct page *page) static void fill_balloon(struct virtio_balloon *vb, size_t num) { - struct balloon_dev_info *vb_dev_info = vb->vb_dev_info; + struct balloon_dev_info *vb_dev_info = &vb->vb_dev_info; /* We can only do one array worth at a time. */ num = min(num, ARRAY_SIZE(vb->pfns)); @@ -171,7 +171,7 @@ static void release_pages_by_pfn(const u32 pfns[], unsigned int num) static void leak_balloon(struct virtio_balloon *vb, size_t num) { struct page *page; - struct balloon_dev_info *vb_dev_info = vb->vb_dev_info; + struct balloon_dev_info *vb_dev_info = &vb->vb_dev_info; /* We can only do one array worth at a time. */ num = min(num, ARRAY_SIZE(vb->pfns)); @@ -353,12 +353,11 @@ static int init_vqs(struct virtio_balloon *vb) return 0; } -static const struct address_space_operations virtio_balloon_aops; #ifdef CONFIG_BALLOON_COMPACTION /* * virtballoon_migratepage - perform the balloon page migration on behalf of * a compation thread. (called under page lock) - * @mapping: the page->mapping which will be assigned to the new migrated page. + * @vb_dev_info: the balloon device * @newpage: page that will replace the isolated page after migration finishes. * @page : the isolated (old) page that is about to be migrated to newpage. * @mode : compaction mode -- not used for balloon page migration. @@ -373,17 +372,13 @@ static const struct address_space_operations virtio_balloon_aops; * This function preforms the balloon page migration task. * Called through balloon_mapping->a_ops->migratepage */ -static int virtballoon_migratepage(struct address_space *mapping, +static int virtballoon_migratepage(struct balloon_dev_info *vb_dev_info, struct page *newpage, struct page *page, enum migrate_mode mode) { - struct balloon_dev_info *vb_dev_info = balloon_page_device(page); - struct virtio_balloon *vb; + struct virtio_balloon *vb = container_of(vb_dev_info, + struct virtio_balloon, vb_dev_info); unsigned long flags; - BUG_ON(!vb_dev_info); - - vb = vb_dev_info->balloon_device; - /* * In order to avoid lock contention while migrating pages concurrently * to leak_balloon() or fill_balloon() we just give up the balloon_lock @@ -399,7 +394,7 @@ static int virtballoon_migratepage(struct address_space *mapping, /* balloon's page migration 1st step -- inflate "newpage" */ spin_lock_irqsave(&vb_dev_info->pages_lock, flags); - balloon_page_insert(newpage, mapping, &vb_dev_info->pages); + balloon_page_insert(vb_dev_info, newpage); vb_dev_info->isolated_pages--; spin_unlock_irqrestore(&vb_dev_info->pages_lock, flags); vb->num_pfns = VIRTIO_BALLOON_PAGES_PER_PAGE; @@ -418,18 +413,11 @@ static int virtballoon_migratepage(struct address_space *mapping, return MIGRATEPAGE_SUCCESS; } - -/* define the balloon_mapping->a_ops callback to allow balloon page migration */ -static const struct address_space_operations virtio_balloon_aops = { - .migratepage = virtballoon_migratepage, -}; #endif /* CONFIG_BALLOON_COMPACTION */ static int virtballoon_probe(struct virtio_device *vdev) { struct virtio_balloon *vb; - struct address_space *vb_mapping; - struct balloon_dev_info *vb_devinfo; int err; vdev->priv = vb = kmalloc(sizeof(*vb), GFP_KERNEL); @@ -445,30 +433,14 @@ static int virtballoon_probe(struct virtio_device *vdev) vb->vdev = vdev; vb->need_stats_update = 0; - vb_devinfo = balloon_devinfo_alloc(vb); - if (IS_ERR(vb_devinfo)) { - err = PTR_ERR(vb_devinfo); - goto out_free_vb; - } - - vb_mapping = balloon_mapping_alloc(vb_devinfo, - (balloon_compaction_check()) ? - &virtio_balloon_aops : NULL); - if (IS_ERR(vb_mapping)) { - /* - * IS_ERR(vb_mapping) && PTR_ERR(vb_mapping) == -EOPNOTSUPP - * This means !CONFIG_BALLOON_COMPACTION, otherwise we get off. - */ - err = PTR_ERR(vb_mapping); - if (err != -EOPNOTSUPP) - goto out_free_vb_devinfo; - } - - vb->vb_dev_info = vb_devinfo; + balloon_devinfo_init(&vb->vb_dev_info); +#ifdef CONFIG_BALLOON_COMPACTION + vb->vb_dev_info.migratepage = virtballoon_migratepage; +#endif err = init_vqs(vb); if (err) - goto out_free_vb_mapping; + goto out_free_vb; vb->thread = kthread_run(balloon, vb, "vballoon"); if (IS_ERR(vb->thread)) { @@ -480,10 +452,6 @@ static int virtballoon_probe(struct virtio_device *vdev) out_del_vqs: vdev->config->del_vqs(vdev); -out_free_vb_mapping: - balloon_mapping_free(vb_mapping); -out_free_vb_devinfo: - balloon_devinfo_free(vb_devinfo); out_free_vb: kfree(vb); out: @@ -509,8 +477,6 @@ static void virtballoon_remove(struct virtio_device *vdev) kthread_stop(vb->thread); remove_common(vb); - balloon_mapping_free(vb->vb_dev_info->mapping); - balloon_devinfo_free(vb->vb_dev_info); kfree(vb); } diff --git a/include/linux/balloon_compaction.h b/include/linux/balloon_compaction.h index 38aa07d..bc3d298 100644 --- a/include/linux/balloon_compaction.h +++ b/include/linux/balloon_compaction.h @@ -57,21 +57,22 @@ * balloon driver as a page book-keeper for its registered balloon devices. */ struct balloon_dev_info { - void *balloon_device; /* balloon device descriptor */ - struct address_space *mapping; /* balloon special page->mapping */ unsigned long isolated_pages; /* # of isolated pages for migration */ spinlock_t pages_lock; /* Protection to pages list */ struct list_head pages; /* Pages enqueued & handled to Host */ + int (*migratepage)(struct balloon_dev_info *, struct page *newpage, + struct page *page, enum migrate_mode mode); }; extern struct page *balloon_page_enqueue(struct balloon_dev_info *b_dev_info); extern struct page *balloon_page_dequeue(struct balloon_dev_info *b_dev_info); -extern struct balloon_dev_info *balloon_devinfo_alloc( - void *balloon_dev_descriptor); -static inline void balloon_devinfo_free(struct balloon_dev_info *b_dev_info) +static inline void balloon_devinfo_init(struct balloon_dev_info *balloon) { - kfree(b_dev_info); + balloon->isolated_pages = 0; + spin_lock_init(&balloon->pages_lock); + INIT_LIST_HEAD(&balloon->pages); + balloon->migratepage = NULL; } #ifdef CONFIG_BALLOON_COMPACTION @@ -79,14 +80,6 @@ extern bool balloon_page_isolate(struct page *page); extern void balloon_page_putback(struct page *page); extern int balloon_page_migrate(struct page *newpage, struct page *page, enum migrate_mode mode); -extern struct address_space -*balloon_mapping_alloc(struct balloon_dev_info *b_dev_info, - const struct address_space_operations *a_ops); - -static inline void balloon_mapping_free(struct address_space *balloon_mapping) -{ - kfree(balloon_mapping); -} /* * __is_movable_balloon_page - helper to perform @page PageBalloon tests @@ -120,27 +113,25 @@ static inline bool isolated_balloon_page(struct page *page) /* * balloon_page_insert - insert a page into the balloon's page list and make - * the page->mapping assignment accordingly. + * the page->private assignment accordingly. + * @balloon : pointer to balloon device * @page : page to be assigned as a 'balloon page' - * @mapping : allocated special 'balloon_mapping' - * @head : balloon's device page list head * * Caller must ensure the page is locked and the spin_lock protecting balloon * pages list is held before inserting a page into the balloon device. */ -static inline void balloon_page_insert(struct page *page, - struct address_space *mapping, - struct list_head *head) +static inline void balloon_page_insert(struct balloon_dev_info *balloon, + struct page *page) { __SetPageBalloon(page); SetPagePrivate(page); - page->mapping = mapping; - list_add(&page->lru, head); + set_page_private(page, (unsigned long)balloon); + list_add(&page->lru, &balloon->pages); } /* * balloon_page_delete - delete a page from balloon's page list and clear - * the page->mapping assignement accordingly. + * the page->private assignement accordingly. * @page : page to be released from balloon's page list * * Caller must ensure the page is locked and the spin_lock protecting balloon @@ -149,7 +140,7 @@ static inline void balloon_page_insert(struct page *page, static inline void balloon_page_delete(struct page *page) { __ClearPageBalloon(page); - page->mapping = NULL; + set_page_private(page, 0); if (PagePrivate(page)) { ClearPagePrivate(page); list_del(&page->lru); @@ -162,11 +153,7 @@ static inline void balloon_page_delete(struct page *page) */ static inline struct balloon_dev_info *balloon_page_device(struct page *page) { - struct address_space *mapping = page->mapping; - if (likely(mapping)) - return mapping->private_data; - - return NULL; + return (struct balloon_dev_info *)page_private(page); } static inline gfp_t balloon_mapping_gfp_mask(void) @@ -174,29 +161,12 @@ static inline gfp_t balloon_mapping_gfp_mask(void) return GFP_HIGHUSER_MOVABLE; } -static inline bool balloon_compaction_check(void) -{ - return true; -} - #else /* !CONFIG_BALLOON_COMPACTION */ -static inline void *balloon_mapping_alloc(void *balloon_device, - const struct address_space_operations *a_ops) +static inline void balloon_page_insert(struct balloon_dev_info *balloon, + struct page *page) { - return ERR_PTR(-EOPNOTSUPP); -} - -static inline void balloon_mapping_free(struct address_space *balloon_mapping) -{ - return; -} - -static inline void balloon_page_insert(struct page *page, - struct address_space *mapping, - struct list_head *head) -{ - list_add(&page->lru, head); + list_add(&page->lru, &balloon->pages); } static inline void balloon_page_delete(struct page *page) @@ -240,9 +210,5 @@ static inline gfp_t balloon_mapping_gfp_mask(void) return GFP_HIGHUSER; } -static inline bool balloon_compaction_check(void) -{ - return false; -} #endif /* CONFIG_BALLOON_COMPACTION */ #endif /* _LINUX_BALLOON_COMPACTION_H */ diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 19191d3..7ea069c 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -24,8 +24,7 @@ enum mapping_flags { AS_ENOSPC = __GFP_BITS_SHIFT + 1, /* ENOSPC on async write */ AS_MM_ALL_LOCKS = __GFP_BITS_SHIFT + 2, /* under mm_take_all_locks() */ AS_UNEVICTABLE = __GFP_BITS_SHIFT + 3, /* e.g., ramdisk, SHM_LOCK */ - AS_BALLOON_MAP = __GFP_BITS_SHIFT + 4, /* balloon page special map */ - AS_EXITING = __GFP_BITS_SHIFT + 5, /* final truncate in progress */ + AS_EXITING = __GFP_BITS_SHIFT + 4, /* final truncate in progress */ }; static inline void mapping_set_error(struct address_space *mapping, int error) @@ -55,21 +54,6 @@ static inline int mapping_unevictable(struct address_space *mapping) return !!mapping; } -static inline void mapping_set_balloon(struct address_space *mapping) -{ - set_bit(AS_BALLOON_MAP, &mapping->flags); -} - -static inline void mapping_clear_balloon(struct address_space *mapping) -{ - clear_bit(AS_BALLOON_MAP, &mapping->flags); -} - -static inline int mapping_balloon(struct address_space *mapping) -{ - return mapping && test_bit(AS_BALLOON_MAP, &mapping->flags); -} - static inline void mapping_set_exiting(struct address_space *mapping) { set_bit(AS_EXITING, &mapping->flags); diff --git a/mm/balloon_compaction.c b/mm/balloon_compaction.c index 52abeeb..3afdabd 100644 --- a/mm/balloon_compaction.c +++ b/mm/balloon_compaction.c @@ -11,32 +11,6 @@ #include <linux/balloon_compaction.h> /* - * balloon_devinfo_alloc - allocates a balloon device information descriptor. - * @balloon_dev_descriptor: pointer to reference the balloon device which - * this struct balloon_dev_info will be servicing. - * - * Driver must call it to properly allocate and initialize an instance of - * struct balloon_dev_info which will be used to reference a balloon device - * as well as to keep track of the balloon device page list. - */ -struct balloon_dev_info *balloon_devinfo_alloc(void *balloon_dev_descriptor) -{ - struct balloon_dev_info *b_dev_info; - b_dev_info = kmalloc(sizeof(*b_dev_info), GFP_KERNEL); - if (!b_dev_info) - return ERR_PTR(-ENOMEM); - - b_dev_info->balloon_device = balloon_dev_descriptor; - b_dev_info->mapping = NULL; - b_dev_info->isolated_pages = 0; - spin_lock_init(&b_dev_info->pages_lock); - INIT_LIST_HEAD(&b_dev_info->pages); - - return b_dev_info; -} -EXPORT_SYMBOL_GPL(balloon_devinfo_alloc); - -/* * balloon_page_enqueue - allocates a new page and inserts it into the balloon * page list. * @b_dev_info: balloon device decriptor where we will insert a new page to @@ -61,7 +35,7 @@ struct page *balloon_page_enqueue(struct balloon_dev_info *b_dev_info) */ BUG_ON(!trylock_page(page)); spin_lock_irqsave(&b_dev_info->pages_lock, flags); - balloon_page_insert(page, b_dev_info->mapping, &b_dev_info->pages); + balloon_page_insert(b_dev_info, page); spin_unlock_irqrestore(&b_dev_info->pages_lock, flags); unlock_page(page); return page; @@ -127,60 +101,10 @@ struct page *balloon_page_dequeue(struct balloon_dev_info *b_dev_info) EXPORT_SYMBOL_GPL(balloon_page_dequeue); #ifdef CONFIG_BALLOON_COMPACTION -/* - * balloon_mapping_alloc - allocates a special ->mapping for ballooned pages. - * @b_dev_info: holds the balloon device information descriptor. - * @a_ops: balloon_mapping address_space_operations descriptor. - * - * Driver must call it to properly allocate and initialize an instance of - * struct address_space which will be used as the special page->mapping for - * balloon device enlisted page instances. - */ -struct address_space *balloon_mapping_alloc(struct balloon_dev_info *b_dev_info, - const struct address_space_operations *a_ops) -{ - struct address_space *mapping; - - mapping = kmalloc(sizeof(*mapping), GFP_KERNEL); - if (!mapping) - return ERR_PTR(-ENOMEM); - - /* - * Give a clean 'zeroed' status to all elements of this special - * balloon page->mapping struct address_space instance. - */ - address_space_init_once(mapping); - - /* - * Set mapping->flags appropriately, to allow balloon pages - * ->mapping identification. - */ - mapping_set_balloon(mapping); - mapping_set_gfp_mask(mapping, balloon_mapping_gfp_mask()); - - /* balloon's page->mapping->a_ops callback descriptor */ - mapping->a_ops = a_ops; - - /* - * Establish a pointer reference back to the balloon device descriptor - * this particular page->mapping will be servicing. - * This is used by compaction / migration procedures to identify and - * access the balloon device pageset while isolating / migrating pages. - * - * As some balloon drivers can register multiple balloon devices - * for a single guest, this also helps compaction / migration to - * properly deal with multiple balloon pagesets, when required. - */ - mapping->private_data = b_dev_info; - b_dev_info->mapping = mapping; - - return mapping; -} -EXPORT_SYMBOL_GPL(balloon_mapping_alloc); static inline void __isolate_balloon_page(struct page *page) { - struct balloon_dev_info *b_dev_info = page->mapping->private_data; + struct balloon_dev_info *b_dev_info = balloon_page_device(page); unsigned long flags; spin_lock_irqsave(&b_dev_info->pages_lock, flags); @@ -192,7 +116,7 @@ static inline void __isolate_balloon_page(struct page *page) static inline void __putback_balloon_page(struct page *page) { - struct balloon_dev_info *b_dev_info = page->mapping->private_data; + struct balloon_dev_info *b_dev_info = balloon_page_device(page); unsigned long flags; spin_lock_irqsave(&b_dev_info->pages_lock, flags); @@ -202,12 +126,6 @@ static inline void __putback_balloon_page(struct page *page) spin_unlock_irqrestore(&b_dev_info->pages_lock, flags); } -static inline int __migrate_balloon_page(struct address_space *mapping, - struct page *newpage, struct page *page, enum migrate_mode mode) -{ - return page->mapping->a_ops->migratepage(mapping, newpage, page, mode); -} - /* __isolate_lru_page() counterpart for a ballooned page */ bool balloon_page_isolate(struct page *page) { @@ -274,7 +192,7 @@ void balloon_page_putback(struct page *page) int balloon_page_migrate(struct page *newpage, struct page *page, enum migrate_mode mode) { - struct address_space *mapping; + struct balloon_dev_info *balloon = balloon_page_device(page); int rc = -EAGAIN; /* @@ -290,9 +208,8 @@ int balloon_page_migrate(struct page *newpage, return rc; } - mapping = page->mapping; - if (mapping) - rc = __migrate_balloon_page(mapping, newpage, page, mode); + if (balloon && balloon->migratepage) + rc = balloon->migratepage(balloon, newpage, page, mode); unlock_page(newpage); return rc; |
