linux-kernel - [PATCH v1 11/23] drivers/virtio/virtio_balloon: stop using balloon_page

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20251021125929.377194-12-david@redhat.com>
Date: Tue, 21 Oct 2025 14:59:16 +0200
From: David Hildenbrand <david@...hat.com>
To: linux-kernel@...r.kernel.org
Cc: linux-mm@...ck.org,
	linuxppc-dev@...ts.ozlabs.org,
	Broadcom internal kernel review list <bcm-kernel-feedback-list@...adcom.com>,
	linux-doc@...r.kernel.org,
	virtualization@...ts.linux.dev,
	David Hildenbrand <david@...hat.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Oscar Salvador <osalvador@...e.de>,
	Lorenzo Stoakes <lorenzo.stoakes@...cle.com>,
	"Liam R. Howlett" <Liam.Howlett@...cle.com>,
	Vlastimil Babka <vbabka@...e.cz>,
	Mike Rapoport <rppt@...nel.org>,
	Suren Baghdasaryan <surenb@...gle.com>,
	Michal Hocko <mhocko@...e.com>,
	Jonathan Corbet <corbet@....net>,
	Madhavan Srinivasan <maddy@...ux.ibm.com>,
	Michael Ellerman <mpe@...erman.id.au>,
	Nicholas Piggin <npiggin@...il.com>,
	Christophe Leroy <christophe.leroy@...roup.eu>,
	Arnd Bergmann <arnd@...db.de>,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	Jerrin Shaji George <jerrin.shaji-george@...adcom.com>,
	"Michael S. Tsirkin" <mst@...hat.com>,
	Jason Wang <jasowang@...hat.com>,
	Xuan Zhuo <xuanzhuo@...ux.alibaba.com>,
	Eugenio Pérez <eperezma@...hat.com>,
	Zi Yan <ziy@...dia.com>
Subject: [PATCH v1 11/23] drivers/virtio/virtio_balloon: stop using balloon_page_push/pop()

Let's stop using these function so we can remove them. They look like
belonging to the balloon API for managing the device balloon list when
really they are just simple helpers only used by virtio-balloon.

Let's just inline them and switch to a proper
list_for_each_entry_safe().

Signed-off-by: David Hildenbrand <david@...hat.com>
---
 drivers/virtio/virtio_balloon.c | 25 +++++++++++++++----------
 1 file changed, 15 insertions(+), 10 deletions(-)

diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
index f7d6a4a6e54f5..4b22de6a5f845 100644
--- a/drivers/virtio/virtio_balloon.c
+++ b/drivers/virtio/virtio_balloon.c
@@ -242,8 +242,8 @@ static void set_page_pfns(struct virtio_balloon *vb,
 static unsigned int fill_balloon(struct virtio_balloon *vb, size_t num)
 {
 	unsigned int num_allocated_pages;
+	struct page *page, *next;
 	unsigned int num_pfns;
-	struct page *page;
 	LIST_HEAD(pages);
 
 	/* We can only do one array worth at a time. */
@@ -262,14 +262,15 @@ static unsigned int fill_balloon(struct virtio_balloon *vb, size_t num)
 			break;
 		}
 
-		balloon_page_push(&pages, page);
+		list_add(&page->lru, &pages);
 	}
 
 	mutex_lock(&vb->balloon_lock);
 
 	vb->num_pfns = 0;
 
-	while ((page = balloon_page_pop(&pages))) {
+	list_for_each_entry_safe(page, next, &pages, lru) {
+		list_del(&page->lru);
 		balloon_page_enqueue(&vb->vb_dev_info, page);
 
 		set_page_pfns(vb, vb->pfns + vb->num_pfns, page);
@@ -474,15 +475,19 @@ static inline s64 towards_target(struct virtio_balloon *vb)
 static unsigned long return_free_pages_to_mm(struct virtio_balloon *vb,
 					     unsigned long num_to_return)
 {
-	struct page *page;
-	unsigned long num_returned;
+	unsigned long num_returned = 0;
+	struct page *page, *next;
+
+	if (unlikely(!num_to_return))
+		return 0;
 
 	spin_lock_irq(&vb->free_page_list_lock);
-	for (num_returned = 0; num_returned < num_to_return; num_returned++) {
-		page = balloon_page_pop(&vb->free_page_list);
-		if (!page)
-			break;
+
+	list_for_each_entry_safe(page, next, &vb->free_page_list, lru) {
+		list_del(&page->lru);
 		__free_pages(page, VIRTIO_BALLOON_HINT_BLOCK_ORDER);
+		if (++num_returned == num_to_return)
+			break;
 	}
 	vb->num_free_page_blocks -= num_returned;
 	spin_unlock_irq(&vb->free_page_list_lock);
@@ -717,7 +722,7 @@ static int get_free_page_and_send(struct virtio_balloon *vb)
 		}
 		virtqueue_kick(vq);
 		spin_lock_irq(&vb->free_page_list_lock);
-		balloon_page_push(&vb->free_page_list, page);
+		list_add(&page->lru, &vb->free_page_list);
 		vb->num_free_page_blocks++;
 		spin_unlock_irq(&vb->free_page_list_lock);
 	} else {
-- 
2.51.0