s390x: register I/O adapters per ISC during init

The I/O adapters should exist as soon as the bus/infrastructure
exists, and not only when the guest is actually trying to do something
with them. While the lazy allocation was not wrong, allocating at init
time is cleaner, both for the architecture and the code. Let's adjust
this by having each device type (currently for PCI and virtio-ccw)
register the adapters for each ISC (as now we don't know which ISC the
guest will use) as soon as it initializes.

Use a two-dimensional array io_adapters[type][isc] to store adapters
in ChannelSubSys, so that we can conveniently get the adapter id by
the helper function css_get_adapter_id(type, isc).

Signed-off-by: Fei Li <sherrylf@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>

diff --git a/hw/s390x/css-bridge.c b/hw/s390x/css-bridge.c
index 9a7f7ee60c2fd34f3d52bddf6acc4b357a58dea4..b54ac01d372b4cb49b688642a2331602e6cf3964 100644 (file)
--- a/hw/s390x/css-bridge.c
+++ b/hw/s390x/css-bridge.c
@@ -107,6 +107,9 @@ VirtualCssBus *virtual_css_bus_init(void)
     /* Enable hotplugging */
     qbus_set_hotplug_handler(bus, dev, &error_abort);
 
+    css_register_io_adapters(CSS_IO_ADAPTER_VIRTIO, true, false,
+                             &error_abort);
+
     return cbus;
  }
 

diff --git a/hw/s390x/css.c b/hw/s390x/css.c
index 1b242c1fb74b4b0461c95858fdbd9c03b4708353..c03bb20bc994a8cba2b87ca82f83b90b0f908c7e 100644 (file)
--- a/hw/s390x/css.c
+++ b/hw/s390x/css.c
@@ -47,7 +47,6 @@ typedef struct IoAdapter {
     uint32_t id;
     uint8_t type;
     uint8_t isc;
-    QTAILQ_ENTRY(IoAdapter) sibling;
 } IoAdapter;
 
 typedef struct ChannelSubSys {
@@ -61,7 +60,7 @@ typedef struct ChannelSubSys {
     uint64_t chnmon_area;
     CssImage *css[MAX_CSSID + 1];
     uint8_t default_cssid;
-    QTAILQ_HEAD(, IoAdapter) io_adapters;
+    IoAdapter *io_adapters[CSS_IO_ADAPTER_TYPE_NUMS][MAX_ISC + 1];
     QTAILQ_HEAD(, IndAddr) indicator_addresses;
 } ChannelSubSys;
 
@@ -72,7 +71,6 @@ static ChannelSubSys channel_subsys = {
     .do_crw_mchk = true,
     .crws_lost = false,
     .chnmon_active = false,
-    .io_adapters = QTAILQ_HEAD_INITIALIZER(channel_subsys.io_adapters),
     .indicator_addresses =
         QTAILQ_HEAD_INITIALIZER(channel_subsys.indicator_addresses),
 };
@@ -155,44 +153,67 @@ int css_create_css_image(uint8_t cssid, bool default_image)
     return 0;
 }
 
-int css_register_io_adapter(CssIoAdapterType type, uint8_t isc, bool swap,
-                            bool maskable, uint32_t *id)
+uint32_t css_get_adapter_id(CssIoAdapterType type, uint8_t isc)
 {
+    if (type >= CSS_IO_ADAPTER_TYPE_NUMS || isc > MAX_ISC ||
+        !channel_subsys.io_adapters[type][isc]) {
+        return -1;
+    }
+
+    return channel_subsys.io_adapters[type][isc]->id;
+}
+
+/**
+ * css_register_io_adapters: Register I/O adapters per ISC during init
+ *
+ * @swap: an indication if byte swap is needed.
+ * @maskable: an indication if the adapter is subject to the mask operation.
+ * @errp: location to store error information.
+ */
+void css_register_io_adapters(CssIoAdapterType type, bool swap, bool maskable,
+                              Error **errp)
+{
+    uint32_t id;
+    int ret, isc;
     IoAdapter *adapter;
-    bool found = false;
-    int ret;
     S390FLICState *fs = s390_get_flic();
     S390FLICStateClass *fsc = S390_FLIC_COMMON_GET_CLASS(fs);
 
-    *id = 0;
-    QTAILQ_FOREACH(adapter, &channel_subsys.io_adapters, sibling) {
-        if ((adapter->type == type) && (adapter->isc == isc)) {
-            *id = adapter->id;
-            found = true;
-            ret = 0;
+    /*
+     * Disallow multiple registrations for the same device type.
+     * Report an error if registering for an already registered type.
+     */
+    if (channel_subsys.io_adapters[type][0]) {
+        error_setg(errp, "Adapters for type %d already registered", type);
+    }
+
+    for (isc = 0; isc <= MAX_ISC; isc++) {
+        id = (type << 3) | isc;
+        ret = fsc->register_io_adapter(fs, id, isc, swap, maskable);
+        if (ret == 0) {
+            adapter = g_new0(IoAdapter, 1);
+            adapter->id = id;
+            adapter->isc = isc;
+            adapter->type = type;
+            channel_subsys.io_adapters[type][isc] = adapter;
+        } else {
+            error_setg_errno(errp, -ret, "Unexpected error %d when "
+                             "registering adapter %d", ret, id);
             break;
         }
-        if (adapter->id >= *id) {
-            *id = adapter->id + 1;
-        }
-    }
-    if (found) {
-        goto out;
     }
-    adapter = g_new0(IoAdapter, 1);
-    ret = fsc->register_io_adapter(fs, *id, isc, swap, maskable);
-    if (ret == 0) {
-        adapter->id = *id;
-        adapter->isc = isc;
-        adapter->type = type;
-        QTAILQ_INSERT_TAIL(&channel_subsys.io_adapters, adapter, sibling);
-    } else {
-        g_free(adapter);
-        fprintf(stderr, "Unexpected error %d when registering adapter %d\n",
-                ret, *id);
+
+    /*
+     * No need to free registered adapters in kvm: kvm will clean up
+     * when the machine goes away.
+     */
+    if (ret) {
+        for (isc--; isc >= 0; isc--) {
+            g_free(channel_subsys.io_adapters[type][isc]);
+            channel_subsys.io_adapters[type][isc] = NULL;
+        }
     }
-out:
-    return ret;
+
 }
 
 static void css_clear_io_interrupt(uint16_t subchannel_id,

diff --git a/hw/s390x/s390-pci-bus.c b/hw/s390x/s390-pci-bus.c
index 1570f2d12ae6625df46d7a3a6e00c64e4135e1b2..a8a1bab50a2a3fb119fb1288f536601f6a027be3 100644 (file)
--- a/hw/s390x/s390-pci-bus.c
+++ b/hw/s390x/s390-pci-bus.c
@@ -581,6 +581,9 @@ static int s390_pcihost_init(SysBusDevice *dev)
     s->bus_no = 0;
     QTAILQ_INIT(&s->pending_sei);
     QTAILQ_INIT(&s->zpci_devs);
+
+    css_register_io_adapters(CSS_IO_ADAPTER_PCI, true, false, &error_abort);
+
     return 0;
 }
 

diff --git a/hw/s390x/s390-pci-inst.c b/hw/s390x/s390-pci-inst.c
index 93980d6b1fe36f5629a50ab2e0dddf8ab67dc2e2..314a9cbad410660a8223b089c039e008c6788ba5 100644 (file)
--- a/hw/s390x/s390-pci-inst.c
+++ b/hw/s390x/s390-pci-inst.c
@@ -733,12 +733,10 @@ int pcistb_service_call(S390CPU *cpu, uint8_t r1, uint8_t r3, uint64_t gaddr,
 static int reg_irqs(CPUS390XState *env, S390PCIBusDevice *pbdev, ZpciFib fib)
 {
     int ret, len;
+    uint8_t isc = FIB_DATA_ISC(ldl_p(&fib.data));
 
-    ret = css_register_io_adapter(CSS_IO_ADAPTER_PCI,
-                                  FIB_DATA_ISC(ldl_p(&fib.data)), true, false,
-                                  &pbdev->routes.adapter.adapter_id);
-    assert(ret == 0);
-
+    pbdev->routes.adapter.adapter_id = css_get_adapter_id(
+                                       CSS_IO_ADAPTER_PCI, isc);
     pbdev->summary_ind = get_indicator(ldq_p(&fib.aisb), sizeof(uint64_t));
     len = BITS_TO_LONGS(FIB_DATA_NOI(ldl_p(&fib.data))) * sizeof(unsigned long);
     pbdev->indicator = get_indicator(ldq_p(&fib.aibv), len);
@@ -757,7 +755,7 @@ static int reg_irqs(CPUS390XState *env, S390PCIBusDevice *pbdev, ZpciFib fib)
     pbdev->routes.adapter.summary_offset = FIB_DATA_AISBO(ldl_p(&fib.data));
     pbdev->routes.adapter.ind_addr = ldq_p(&fib.aibv);
     pbdev->routes.adapter.ind_offset = FIB_DATA_AIBVO(ldl_p(&fib.data));
-    pbdev->isc = FIB_DATA_ISC(ldl_p(&fib.data));
+    pbdev->isc = isc;
     pbdev->noi = FIB_DATA_NOI(ldl_p(&fib.data));
     pbdev->sum = FIB_DATA_SUM(ldl_p(&fib.data));
 

diff --git a/hw/s390x/virtio-ccw.c b/hw/s390x/virtio-ccw.c
index b728439d40604f8577f48519825006c990cf5ac4..f376381b9c91f7e1f82b213124d0cf823c2bfa1e 100644 (file)
--- a/hw/s390x/virtio-ccw.c
+++ b/hw/s390x/virtio-ccw.c
@@ -616,10 +616,9 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw)
                 dev->routes.adapter.ind_offset = ind_bit;
                 dev->routes.adapter.summary_offset = 7;
                 cpu_physical_memory_unmap(thinint, hw_len, 0, hw_len);
-                ret = css_register_io_adapter(CSS_IO_ADAPTER_VIRTIO,
-                                              dev->thinint_isc, true, false,
-                                              &dev->routes.adapter.adapter_id);
-                assert(ret == 0);
+                dev->routes.adapter.adapter_id = css_get_adapter_id(
+                                                 CSS_IO_ADAPTER_VIRTIO,
+                                                 dev->thinint_isc);
                 sch->thinint_active = ((dev->indicators != NULL) &&
                                        (dev->summary_indicator != NULL));
                 sch->curr_status.scsw.count = ccw.count - len;
@@ -1308,9 +1307,9 @@ static int virtio_ccw_load_config(DeviceState *d, QEMUFile *f)
     dev->thinint_isc = qemu_get_byte(f);
     dev->revision = qemu_get_be32(f);
     if (s->thinint_active) {
-        return css_register_io_adapter(CSS_IO_ADAPTER_VIRTIO,
-                                       dev->thinint_isc, true, false,
-                                       &dev->routes.adapter.adapter_id);
+        dev->routes.adapter.adapter_id = css_get_adapter_id(
+                                         CSS_IO_ADAPTER_VIRTIO,
+                                         dev->thinint_isc);
     }
 
     return 0;

diff --git a/include/hw/s390x/css.h b/include/hw/s390x/css.h
index cdc73fe0aae964d281e67b5318cdddb0f29f9fdf..f1f0d7f07a0be4ee2cc04e4abace927a12546e01 100644 (file)
--- a/include/hw/s390x/css.h
+++ b/include/hw/s390x/css.h
@@ -23,6 +23,8 @@
 #define MAX_CSSID 255
 #define MAX_CHPID 255
 
+#define MAX_ISC 7
+
 #define MAX_CIWS 62
 
 #define VIRTUAL_CSSID 0xfe
@@ -130,8 +132,9 @@ typedef enum {
     CSS_IO_ADAPTER_TYPE_NUMS,
 } CssIoAdapterType;
 
-int css_register_io_adapter(CssIoAdapterType type, uint8_t isc, bool swap,
-                            bool maskable, uint32_t *id);
+uint32_t css_get_adapter_id(CssIoAdapterType type, uint8_t isc);
+void css_register_io_adapters(CssIoAdapterType type, bool swap, bool maskable,
+                              Error **errp);
 
 #ifndef CONFIG_USER_ONLY
 SubchDev *css_find_subch(uint8_t m, uint8_t cssid, uint8_t ssid,