Commit 7bca3892 authored by Cornelia Huck's avatar Cornelia Huck
Browse files

s390x/virtio-ccw: reference-counted indicators 



Make code using the same indicators point to a single allocated structure
that is freed when the last user goes away.

This will be used by the irqfd code to unmap addresses after the last user
is gone.

Reviewed-by: default avatarThomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: default avatarChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: default avatarCornelia Huck <cornelia.huck@de.ibm.com>
parent 03cf077a

hw/s390x/virtio-ccw.c

+63 −17
Original line number Diff line number Diff line
@@ -27,6 +27,38 @@ 
#include "virtio-ccw.h"

#include "trace.h"



static QTAILQ_HEAD(, IndAddr) indicator_addresses =

    QTAILQ_HEAD_INITIALIZER(indicator_addresses);



static IndAddr *get_indicator(hwaddr ind_addr, int len)

{

    IndAddr *indicator;



    QTAILQ_FOREACH(indicator, &indicator_addresses, sibling) {

        if (indicator->addr == ind_addr) {

            indicator->refcnt++;

            return indicator;

        }

    }

    indicator = g_new0(IndAddr, 1);

    indicator->addr = ind_addr;

    indicator->len = len;

    indicator->refcnt = 1;

    QTAILQ_INSERT_TAIL(&indicator_addresses, indicator, sibling);

    return indicator;

}



static void release_indicator(IndAddr *indicator)

{

    assert(indicator->refcnt > 0);

    indicator->refcnt--;

    if (indicator->refcnt > 0) {

        return;

    }

    QTAILQ_REMOVE(&indicator_addresses, indicator, sibling);

    g_free(indicator);

}



static void virtio_ccw_bus_new(VirtioBusState *bus, size_t bus_size,

                               VirtioCcwDevice *dev);
@@ -445,7 +477,7 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw) 
            ret = -EFAULT;

        } else {

            indicators = ldq_phys(&address_space_memory, ccw.cda);

            dev->indicators = indicators;

            dev->indicators = get_indicator(indicators, sizeof(uint64_t));

            sch->curr_status.scsw.count = ccw.count - sizeof(indicators);

            ret = 0;

        }
@@ -465,7 +497,7 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw) 
            ret = -EFAULT;

        } else {

            indicators = ldq_phys(&address_space_memory, ccw.cda);

            dev->indicators2 = indicators;

            dev->indicators2 = get_indicator(indicators, sizeof(uint64_t));

            sch->curr_status.scsw.count = ccw.count - sizeof(indicators);

            ret = 0;

        }
@@ -517,8 +549,10 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw) 
                ret = -EFAULT;

            } else {

                len = hw_len;

                dev->summary_indicator = thinint->summary_indicator;

                dev->indicators = thinint->device_indicator;

                dev->summary_indicator =

                    get_indicator(thinint->summary_indicator, sizeof(uint8_t));

                dev->indicators = get_indicator(thinint->device_indicator,

                                                thinint->ind_bit / 8 + 1);

                dev->thinint_isc = thinint->isc;

                dev->ind_bit = thinint->ind_bit;

                cpu_physical_memory_unmap(thinint, hw_len, 0, hw_len);
@@ -526,8 +560,8 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw) 
                                              dev->thinint_isc, true, false,

                                              &dev->adapter_id);

                assert(ret == 0);

                sch->thinint_active = ((dev->indicators != 0) &&

                                       (dev->summary_indicator != 0));

                sch->thinint_active = ((dev->indicators != NULL) &&

                                       (dev->summary_indicator != NULL));

                sch->curr_status.scsw.count = ccw.count - len;

                ret = 0;

            }
@@ -558,7 +592,7 @@ static int virtio_ccw_device_init(VirtioCcwDevice *dev, VirtIODevice *vdev) 
    sch->driver_data = dev;

    dev->sch = sch;



    dev->indicators = 0;

    dev->indicators = NULL;



    /* Initialize subchannel structure. */

    sch->channel_prog = 0x0;
@@ -697,7 +731,10 @@ static int virtio_ccw_exit(VirtioCcwDevice *dev) 
        css_subch_assign(sch->cssid, sch->ssid, sch->schid, sch->devno, NULL);

        g_free(sch);

    }

    dev->indicators = 0;

    if (dev->indicators) {

        release_indicator(dev->indicators);

        dev->indicators = NULL;

    }

    return 0;

}
@@ -954,17 +991,17 @@ static void virtio_ccw_notify(DeviceState *d, uint16_t vector) 
             * ind_bit indicates the start of the indicators in a big

             * endian notation.

             */

            virtio_set_ind_atomic(sch, dev->indicators +

            virtio_set_ind_atomic(sch, dev->indicators->addr +

                                  (dev->ind_bit + vector) / 8,

                                  0x80 >> ((dev->ind_bit + vector) % 8));

            if (!virtio_set_ind_atomic(sch, dev->summary_indicator,

            if (!virtio_set_ind_atomic(sch, dev->summary_indicator->addr,

                                       0x01)) {

                css_adapter_interrupt(dev->thinint_isc);

            }

        } else {

            indicators = ldq_phys(&address_space_memory, dev->indicators);

            indicators = ldq_phys(&address_space_memory, dev->indicators->addr);

            indicators |= 1ULL << vector;

            stq_phys(&address_space_memory, dev->indicators, indicators);

            stq_phys(&address_space_memory, dev->indicators->addr, indicators);

            css_conditional_io_interrupt(sch);

        }

    } else {
@@ -972,9 +1009,9 @@ static void virtio_ccw_notify(DeviceState *d, uint16_t vector) 
            return;

        }

        vector = 0;

        indicators = ldq_phys(&address_space_memory, dev->indicators2);

        indicators = ldq_phys(&address_space_memory, dev->indicators2->addr);

        indicators |= 1ULL << vector;

        stq_phys(&address_space_memory, dev->indicators2, indicators);

        stq_phys(&address_space_memory, dev->indicators2->addr, indicators);

        css_conditional_io_interrupt(sch);

    }

}
@@ -995,9 +1032,18 @@ static void virtio_ccw_reset(DeviceState *d) 
    virtio_ccw_stop_ioeventfd(dev);

    virtio_reset(vdev);

    css_reset_sch(dev->sch);

    dev->indicators = 0;

    dev->indicators2 = 0;

    dev->summary_indicator = 0;

    if (dev->indicators) {

        release_indicator(dev->indicators);

        dev->indicators = NULL;

    }

    if (dev->indicators2) {

        release_indicator(dev->indicators2);

        dev->indicators2 = NULL;

    }

    if (dev->summary_indicator) {

        release_indicator(dev->summary_indicator);

        dev->summary_indicator = NULL;

    }

}



static void virtio_ccw_vmstate_change(DeviceState *d, bool running)

hw/s390x/virtio-ccw.h

+10 −3
Original line number Diff line number Diff line
@@ -75,6 +75,13 @@ typedef struct VirtIOCCWDeviceClass { 
#define VIRTIO_CCW_FLAG_USE_IOEVENTFD_BIT 1

#define VIRTIO_CCW_FLAG_USE_IOEVENTFD   (1 << VIRTIO_CCW_FLAG_USE_IOEVENTFD_BIT)



typedef struct IndAddr {

    hwaddr addr;

    unsigned long refcnt;

    int len;

    QTAILQ_ENTRY(IndAddr) sibling;

} IndAddr;



struct VirtioCcwDevice {

    DeviceState parent_obj;

    SubchDev *sch;
@@ -87,9 +94,9 @@ struct VirtioCcwDevice { 
    uint8_t thinint_isc;

    uint32_t adapter_id;

    /* Guest provided values: */

    hwaddr indicators;

    hwaddr indicators2;

    hwaddr summary_indicator;

    IndAddr *indicators;

    IndAddr *indicators2;

    IndAddr *summary_indicator;

    uint64_t ind_bit;

};