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| author | Michael S. Tsirkin <mst@redhat.com> | 2015-04-15 10:17:43 +0930 |
|---|---|---|
| committer | Rusty Russell <rusty@rustcorp.com.au> | 2015-04-15 12:41:09 +0930 |
| commit | df81b29c7b81b9d70ee29b7a263dd5009daa0ce4 (patch) | |
| tree | a73a9ac6aa72aa32bd7e25a25148044025caa31f /drivers/virtio | |
| parent | 9e1a27ea42691429e31f158cce6fc61bc79bb2e9 (diff) | |
| download | lwn-df81b29c7b81b9d70ee29b7a263dd5009daa0ce4.tar.gz lwn-df81b29c7b81b9d70ee29b7a263dd5009daa0ce4.zip | |
virtio_balloon: transitional interface
Virtio 1.0 doesn't include a modern balloon device.
But it's not a big change to support a transitional
balloon device: this has the advantage of supporting
existing drivers, transparently.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Diffstat (limited to 'drivers/virtio')
| -rw-r--r-- | drivers/virtio/virtio_balloon.c | 21 |
1 files changed, 15 insertions, 6 deletions
diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c index 6a356e344f82..82e80e034f25 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -214,8 +214,8 @@ static inline void update_stat(struct virtio_balloon *vb, int idx, u16 tag, u64 val) { BUG_ON(idx >= VIRTIO_BALLOON_S_NR); - vb->stats[idx].tag = tag; - vb->stats[idx].val = val; + vb->stats[idx].tag = cpu_to_virtio16(vb->vdev, tag); + vb->stats[idx].val = cpu_to_virtio64(vb->vdev, val); } #define pages_to_bytes(x) ((u64)(x) << PAGE_SHIFT) @@ -283,18 +283,27 @@ static void virtballoon_changed(struct virtio_device *vdev) static inline s64 towards_target(struct virtio_balloon *vb) { - __le32 v; s64 target; + u32 num_pages; - virtio_cread(vb->vdev, struct virtio_balloon_config, num_pages, &v); + virtio_cread(vb->vdev, struct virtio_balloon_config, num_pages, + &num_pages); - target = le32_to_cpu(v); + /* Legacy balloon config space is LE, unlike all other devices. */ + if (!virtio_has_feature(vb->vdev, VIRTIO_F_VERSION_1)) + num_pages = le32_to_cpu((__force __le32)num_pages); + + target = num_pages; return target - vb->num_pages; } static void update_balloon_size(struct virtio_balloon *vb) { - __le32 actual = cpu_to_le32(vb->num_pages); + u32 actual = vb->num_pages; + + /* Legacy balloon config space is LE, unlike all other devices. */ + if (!virtio_has_feature(vb->vdev, VIRTIO_F_VERSION_1)) + actual = (__force u32)cpu_to_le32(actual); virtio_cwrite(vb->vdev, struct virtio_balloon_config, actual, &actual); |