drivers/virtio/virtio_balloon: stop using balloon_page_push/pop()

Let's stop using these functions 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().

Link: https://lkml.kernel.org/r/20260119230133.3551867-13-david@kernel.org
Signed-off-by: David Hildenbrand (Red Hat) <david@kernel.org>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Eugenio Pérez <eperezma@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Jerrin Shaji George <jerrin.shaji-george@broadcom.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: SeongJae Park <sj@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
index 15c1cf5fd249c682ab3a4c975cfb2afc0dee60ee..6ae00de78b61bbd257285f255b8824ed4174ae4d 100644 (file)
--- 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 {