[v1,4/5] hw/vfio/ap: Storing event information for an AP configuration change event

Commit Message

Rorie Reyes Jan. 7, 2025, 6:43 p.m. UTC

These functions can be invoked by the function that handles interception
of the CHSC SEI instruction for requests indicating the accessibility of
one or more adjunct processors has changed.

Signed-off-by: Rorie Reyes <[e-mail]>
---
 hw/vfio/ap.c                 | 37 ++++++++++++++++++++++++++++++++++++
 include/hw/s390x/ap-bridge.h | 17 +++++++++++++++++
 2 files changed, 54 insertions(+)

Patch

diff --git a/hw/vfio/ap.c b/hw/vfio/ap.c
index 508c6eed7a..9d1e18f100 100644
--- a/hw/vfio/ap.c
+++ b/hw/vfio/ap.c
@@ -94,6 +94,43 @@  static void vfio_ap_cfg_chg_notifier_handler(void *opaque)
     css_generate_css_crws(0);
 }
 
+int ap_chsc_sei_nt0_get_event(void *res)
+{
+    APConfigChgEvent *cfg_chg_event = QTAILQ_FIRST(&cfg_chg_events);
+    ChscSeiNt0Res *nt0_res  = (ChscSeiNt0Res *)res;
+    memset(nt0_res, 0, sizeof(*nt0_res));
+    int rc = 1;
+
+    if (cfg_chg_event) {
+        QTAILQ_REMOVE(&cfg_chg_events, cfg_chg_event, next);
+        free(cfg_chg_event);
+
+        /*
+         * If there are any AP configuration change events in the queue,
+         * indicate to the caller that there is pending event info in
+         * the response block
+         */
+        if (!QTAILQ_EMPTY(&cfg_chg_events)) {
+            nt0_res->flags |= PENDING_EVENT_INFO_BITMASK;
+        }
+
+        nt0_res->length = sizeof(ChscSeiNt0Res);
+        nt0_res->code = 1;
+        nt0_res->nt = 0;
+        nt0_res->rs = 5;
+        nt0_res->cc = 3;
+
+        rc = 0;
+    }
+
+    return rc;
+}
+
+int ap_chsc_sei_nt0_have_event(void)
+{
+    return !QTAILQ_EMPTY(&cfg_chg_events);
+}
+
 static bool vfio_ap_register_irq_notifier(VFIOAPDevice *vapdev,
                                           unsigned int irq, Error **errp)
 {
diff --git a/include/hw/s390x/ap-bridge.h b/include/hw/s390x/ap-bridge.h
index 470e439a98..c9beec3db4 100644
--- a/include/hw/s390x/ap-bridge.h
+++ b/include/hw/s390x/ap-bridge.h
@@ -16,4 +16,21 @@ 
 
 void s390_init_ap(void);
 
+typedef struct ChscSeiNt0Res {
+    uint16_t length;
+    uint16_t code;
+    uint8_t reserved1;
+    uint16_t reserved2;
+    uint8_t nt;
+#define PENDING_EVENT_INFO_BITMASK 0x80;
+    uint8_t flags;
+    uint8_t reserved3;
+    uint8_t rs;
+    uint8_t cc;
+} QEMU_PACKED ChscSeiNt0Res;
+
+int ap_chsc_sei_nt0_get_event(void *res);
+
+int ap_chsc_sei_nt0_have_event(void);
+
 #endif