s390x/virtio-ccw: Adapter interrupt support.
Handle the new CCW_CMD_SET_IND_ADAPTER command enabling adapter interrupts
on guest request. When active, host->guest notifications will be handled
via global_indicator -> queue indicators instead of queue indicators +
subchannel I/O interrupt. Indicators for virtqueues may be present at an
offset.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
diff --git a/hw/s390x/virtio-ccw.c b/hw/s390x/virtio-ccw.c
index f6e0e3e..a01801e 100644
--- a/hw/s390x/virtio-ccw.c
+++ b/hw/s390x/virtio-ccw.c
@@ -1,7 +1,7 @@
/*
* virtio ccw target implementation
*
- * Copyright 2012 IBM Corp.
+ * Copyright 2012,2014 IBM Corp.
* Author(s): Cornelia Huck <cornelia.huck@de.ibm.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or (at
@@ -188,6 +188,13 @@
uint8_t index;
} QEMU_PACKED VirtioFeatDesc;
+typedef struct VirtioThinintInfo {
+ hwaddr summary_indicator;
+ hwaddr device_indicator;
+ uint64_t ind_bit;
+ uint8_t isc;
+} QEMU_PACKED VirtioThinintInfo;
+
/* Specify where the virtqueues for the subchannel are in guest memory. */
static int virtio_ccw_set_vqs(SubchDev *sch, uint64_t addr, uint32_t align,
uint16_t index, uint16_t num)
@@ -237,6 +244,7 @@
bool check_len;
int len;
hwaddr hw_len;
+ VirtioThinintInfo *thinint;
if (!dev) {
return -EINVAL;
@@ -428,6 +436,11 @@
ret = -EINVAL;
break;
}
+ if (sch->thinint_active) {
+ /* Trigger a command reject. */
+ ret = -ENOSYS;
+ break;
+ }
if (!ccw.cda) {
ret = -EFAULT;
} else {
@@ -480,6 +493,42 @@
ret = 0;
}
break;
+ case CCW_CMD_SET_IND_ADAPTER:
+ if (check_len) {
+ if (ccw.count != sizeof(*thinint)) {
+ ret = -EINVAL;
+ break;
+ }
+ } else if (ccw.count < sizeof(*thinint)) {
+ /* Can't execute command. */
+ ret = -EINVAL;
+ break;
+ }
+ len = sizeof(*thinint);
+ hw_len = len;
+ if (!ccw.cda) {
+ ret = -EFAULT;
+ } else if (dev->indicators && !sch->thinint_active) {
+ /* Trigger a command reject. */
+ ret = -ENOSYS;
+ } else {
+ thinint = cpu_physical_memory_map(ccw.cda, &hw_len, 0);
+ if (!thinint) {
+ ret = -EFAULT;
+ } else {
+ len = hw_len;
+ dev->summary_indicator = thinint->summary_indicator;
+ dev->indicators = thinint->device_indicator;
+ dev->thinint_isc = thinint->isc;
+ dev->ind_bit = thinint->ind_bit;
+ cpu_physical_memory_unmap(thinint, hw_len, 0, hw_len);
+ sch->thinint_active = ((dev->indicators != 0) &&
+ (dev->summary_indicator != 0));
+ sch->curr_status.scsw.count = ccw.count - len;
+ ret = 0;
+ }
+ }
+ break;
default:
ret = -ENOSYS;
break;
@@ -511,6 +560,7 @@
sch->channel_prog = 0x0;
sch->last_cmd_valid = false;
sch->orb = NULL;
+ sch->thinint_active = false;
/*
* Use a device number if provided. Otherwise, fall back to subchannel
* number.
@@ -858,6 +908,28 @@
return container_of(d, VirtioCcwDevice, parent_obj);
}
+static uint8_t virtio_set_ind_atomic(SubchDev *sch, uint64_t ind_loc,
+ uint8_t to_be_set)
+{
+ uint8_t ind_old, ind_new;
+ hwaddr len = 1;
+ uint8_t *ind_addr;
+
+ ind_addr = cpu_physical_memory_map(ind_loc, &len, 1);
+ if (!ind_addr) {
+ error_report("%s(%x.%x.%04x): unable to access indicator",
+ __func__, sch->cssid, sch->ssid, sch->schid);
+ return -1;
+ }
+ do {
+ ind_old = *ind_addr;
+ ind_new = ind_old | to_be_set;
+ } while (atomic_cmpxchg(ind_addr, ind_old, ind_new) != ind_old);
+ cpu_physical_memory_unmap(ind_addr, len, 1, len);
+
+ return ind_old;
+}
+
static void virtio_ccw_notify(DeviceState *d, uint16_t vector)
{
VirtioCcwDevice *dev = to_virtio_ccw_dev_fast(d);
@@ -872,9 +944,26 @@
if (!dev->indicators) {
return;
}
- indicators = ldq_phys(&address_space_memory, dev->indicators);
- indicators |= 1ULL << vector;
- stq_phys(&address_space_memory, dev->indicators, indicators);
+ if (sch->thinint_active) {
+ /*
+ * In the adapter interrupt case, indicators points to a
+ * memory area that may be (way) larger than 64 bit and
+ * ind_bit indicates the start of the indicators in a big
+ * endian notation.
+ */
+ virtio_set_ind_atomic(sch, dev->indicators +
+ (dev->ind_bit + vector) / 8,
+ 0x80 >> ((dev->ind_bit + vector) % 8));
+ if (!virtio_set_ind_atomic(sch, dev->summary_indicator,
+ 0x01)) {
+ css_adapter_interrupt(dev->thinint_isc);
+ }
+ } else {
+ indicators = ldq_phys(&address_space_memory, dev->indicators);
+ indicators |= 1ULL << vector;
+ stq_phys(&address_space_memory, dev->indicators, indicators);
+ css_conditional_io_interrupt(sch);
+ }
} else {
if (!dev->indicators2) {
return;
@@ -883,10 +972,8 @@
indicators = ldq_phys(&address_space_memory, dev->indicators2);
indicators |= 1ULL << vector;
stq_phys(&address_space_memory, dev->indicators2, indicators);
+ css_conditional_io_interrupt(sch);
}
-
- css_conditional_io_interrupt(sch);
-
}
static unsigned virtio_ccw_get_features(DeviceState *d)
@@ -907,6 +994,7 @@
css_reset_sch(dev->sch);
dev->indicators = 0;
dev->indicators2 = 0;
+ dev->summary_indicator = 0;
}
static void virtio_ccw_vmstate_change(DeviceState *d, bool running)
