From 9d1ba8056474a208ed9efb7e58cd014795d9f818 Mon Sep 17 00:00:00 2001 From: Konstantin Khlebnikov Date: Thu, 9 Oct 2014 15:29:29 -0700 Subject: mm/balloon_compaction: remove balloon mapping and flag AS_BALLOON_MAP Now ballooned pages are detected using PageBalloon(). Fake mapping is no longer required. This patch links ballooned pages to balloon device using field page->private instead of page->mapping. Also this patch embeds balloon_dev_info directly into struct virtio_balloon. Signed-off-by: Konstantin Khlebnikov Cc: Rafael Aquini Cc: Andrey Ryabinin Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/virtio/virtio_balloon.c | 60 +++++++++-------------------------------- 1 file changed, 13 insertions(+), 47 deletions(-) (limited to 'drivers/virtio') diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c index c3eb93fc9261..2bad7f9dd2ac 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); } -- cgit v1.2.3-70-g09d2