diff options
-rw-r--r-- | drivers/virtio/virtio_balloon.c | 13 | ||||
-rw-r--r-- | include/linux/virtio_balloon.h | 3 |
2 files changed, 14 insertions, 2 deletions
diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c index 62eab43152d..59268266b79 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c | |||
@@ -56,6 +56,15 @@ static struct virtio_device_id id_table[] = { | |||
56 | { 0 }, | 56 | { 0 }, |
57 | }; | 57 | }; |
58 | 58 | ||
59 | static u32 page_to_balloon_pfn(struct page *page) | ||
60 | { | ||
61 | unsigned long pfn = page_to_pfn(page); | ||
62 | |||
63 | BUILD_BUG_ON(PAGE_SHIFT < VIRTIO_BALLOON_PFN_SHIFT); | ||
64 | /* Convert pfn from Linux page size to balloon page size. */ | ||
65 | return pfn >> (PAGE_SHIFT - VIRTIO_BALLOON_PFN_SHIFT); | ||
66 | } | ||
67 | |||
59 | static void balloon_ack(struct virtqueue *vq) | 68 | static void balloon_ack(struct virtqueue *vq) |
60 | { | 69 | { |
61 | struct virtio_balloon *vb; | 70 | struct virtio_balloon *vb; |
@@ -99,7 +108,7 @@ static void fill_balloon(struct virtio_balloon *vb, size_t num) | |||
99 | msleep(200); | 108 | msleep(200); |
100 | break; | 109 | break; |
101 | } | 110 | } |
102 | vb->pfns[vb->num_pfns] = page_to_pfn(page); | 111 | vb->pfns[vb->num_pfns] = page_to_balloon_pfn(page); |
103 | totalram_pages--; | 112 | totalram_pages--; |
104 | vb->num_pages++; | 113 | vb->num_pages++; |
105 | list_add(&page->lru, &vb->pages); | 114 | list_add(&page->lru, &vb->pages); |
@@ -132,7 +141,7 @@ static void leak_balloon(struct virtio_balloon *vb, size_t num) | |||
132 | for (vb->num_pfns = 0; vb->num_pfns < num; vb->num_pfns++) { | 141 | for (vb->num_pfns = 0; vb->num_pfns < num; vb->num_pfns++) { |
133 | page = list_first_entry(&vb->pages, struct page, lru); | 142 | page = list_first_entry(&vb->pages, struct page, lru); |
134 | list_del(&page->lru); | 143 | list_del(&page->lru); |
135 | vb->pfns[vb->num_pfns] = page_to_pfn(page); | 144 | vb->pfns[vb->num_pfns] = page_to_balloon_pfn(page); |
136 | vb->num_pages--; | 145 | vb->num_pages--; |
137 | } | 146 | } |
138 | 147 | ||
diff --git a/include/linux/virtio_balloon.h b/include/linux/virtio_balloon.h index c30c7bfbf39..8726ff77763 100644 --- a/include/linux/virtio_balloon.h +++ b/include/linux/virtio_balloon.h | |||
@@ -10,6 +10,9 @@ | |||
10 | /* The feature bitmap for virtio balloon */ | 10 | /* The feature bitmap for virtio balloon */ |
11 | #define VIRTIO_BALLOON_F_MUST_TELL_HOST 0 /* Tell before reclaiming pages */ | 11 | #define VIRTIO_BALLOON_F_MUST_TELL_HOST 0 /* Tell before reclaiming pages */ |
12 | 12 | ||
13 | /* Size of a PFN in the balloon interface. */ | ||
14 | #define VIRTIO_BALLOON_PFN_SHIFT 12 | ||
15 | |||
13 | struct virtio_balloon_config | 16 | struct virtio_balloon_config |
14 | { | 17 | { |
15 | /* Number of pages host wants Guest to give up. */ | 18 | /* Number of pages host wants Guest to give up. */ |