Comment 8 for bug 1887930

------- Comment From <email address hidden> 2020-09-10 11:46 EDT-------
(In reply to comment #19)
...snip...
> If you want to drive this forward to FOCAL as well it might be useful to
> provide us a header update with just exactly what you need instead.

As far as the header update in QEMU goes, these two kernel commits are the ones involved:

d8cac29b1d52 vfio-ccw: Introduce a new CRW region
24c986748ba6 vfio-ccw: Introduce a new schib region

With those applied to kernel 5.4, the following diff is the important hunk for QEMU. Should apply to https://git.launchpad.net/~usd-import-team/ubuntu/+source/qemu branch origin/ubuntu/focal-devel

diff --git a/linux-headers/linux/vfio.h b/linux-headers/linux/vfio.h
index fb10370d2..9e227348b 100644
--- a/linux-headers/linux/vfio.h
+++ b/linux-headers/linux/vfio.h
@@ -378,6 +378,8 @@ struct vfio_region_gfx_edid {
/* sub-types for VFIO_REGION_TYPE_CCW */
#define VFIO_REGION_SUBTYPE_CCW_ASYNC_CMD (1)
+#define VFIO_REGION_SUBTYPE_CCW_SCHIB (2)
+#define VFIO_REGION_SUBTYPE_CCW_CRW (3)

/*
* The MSIX mappable capability informs that MSIX data of a BAR can be mmapped
@@ -577,6 +579,7 @@ enum {

enum {
VFIO_CCW_IO_IRQ_INDEX,
+ VFIO_CCW_CRW_IRQ_INDEX,
VFIO_CCW_NUM_IRQS
};

diff --git a/linux-headers/linux/vfio_ccw.h b/linux-headers/linux/vfio_ccw.h
index fcc3e69ef..516496f1d 100644
--- a/linux-headers/linux/vfio_ccw.h
+++ b/linux-headers/linux/vfio_ccw.h
@@ -34,4 +34,23 @@ struct ccw_cmd_region {
__u32 ret_code;
} __attribute__((packed));

+/*
+ * Used for processing commands that read the subchannel-information block
+ * Reading this region triggers a stsch() to hardware
+ * Note: this is controlled by a capability
+ */
+struct ccw_schib_region {
+#define SCHIB_AREA_SIZE 52
+ __u8 schib_area[SCHIB_AREA_SIZE];
+} __attribute__((packed));
+
+/*
+ * Used for returning a Channel Report Word to userspace.
+ * Note: this is controlled by a capability
+ */
+struct ccw_crw_region {
+ __u32 crw;
+ __u32 pad;
+} __attribute__((packed));
+
#endif