From 3a553fc65826e0e682ed0fff770ad0d421c6d407 Mon Sep 17 00:00:00 2001 From: Jens Freimann Date: Tue, 16 Jul 2013 09:04:04 +0200 Subject: s390x/kvm: implement floating-interrupt controller device This patch implements a floating-interrupt controller device (flic) which interacts with the s390 flic kvm_device. Signed-off-by: Jens Freimann Reviewed-by: Cornelia Huck Signed-off-by: Christian Borntraeger --- hw/intc/Makefile.objs | 1 + hw/intc/s390_flic.c | 286 ++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 287 insertions(+) create mode 100644 hw/intc/s390_flic.c (limited to 'hw/intc') diff --git a/hw/intc/Makefile.objs b/hw/intc/Makefile.objs index 60eb936e0d..c8a2318d56 100644 --- a/hw/intc/Makefile.objs +++ b/hw/intc/Makefile.objs @@ -25,3 +25,4 @@ obj-$(CONFIG_SH4) += sh_intc.o obj-$(CONFIG_XICS) += xics.o obj-$(CONFIG_XICS_KVM) += xics_kvm.o obj-$(CONFIG_ALLWINNER_A10_PIC) += allwinner-a10-pic.o +obj-$(CONFIG_S390_FLIC) += s390_flic.o diff --git a/hw/intc/s390_flic.c b/hw/intc/s390_flic.c new file mode 100644 index 0000000000..1a7876da78 --- /dev/null +++ b/hw/intc/s390_flic.c @@ -0,0 +1,286 @@ +/* + * QEMU S390x KVM floating interrupt controller (flic) + * + * Copyright 2014 IBM Corp. + * Author(s): Jens Freimann + * + * This work is licensed under the terms of the GNU GPL, version 2 or (at + * your option) any later version. See the COPYING file in the top-level + * directory. + */ + +#include +#include "qemu/error-report.h" +#include "hw/sysbus.h" +#include "sysemu/kvm.h" +#include "migration/qemu-file.h" +#include "hw/s390x/s390_flic.h" +#include "trace.h" + +#define FLIC_SAVE_INITIAL_SIZE getpagesize() +#define FLIC_FAILED (-1UL) +#define FLIC_SAVEVM_VERSION 1 + +void s390_flic_init(void) +{ + DeviceState *dev; + int r; + + if (kvm_enabled()) { + dev = qdev_create(NULL, "s390-flic"); + object_property_add_child(qdev_get_machine(), "s390-flic", + OBJECT(dev), NULL); + r = qdev_init(dev); + if (r) { + error_report("flic: couldn't create qdev"); + } + } +} + +/** + * flic_get_all_irqs - store all pending irqs in buffer + * @buf: pointer to buffer which is passed to kernel + * @len: length of buffer + * @flic: pointer to flic device state + * + * Returns: -ENOMEM if buffer is too small, + * -EINVAL if attr.group is invalid, + * -EFAULT if copying to userspace failed, + * on success return number of stored interrupts + */ +static int flic_get_all_irqs(KVMS390FLICState *flic, + void *buf, int len) +{ + struct kvm_device_attr attr = { + .group = KVM_DEV_FLIC_GET_ALL_IRQS, + .addr = (uint64_t) buf, + .attr = len, + }; + int rc; + + rc = ioctl(flic->fd, KVM_GET_DEVICE_ATTR, &attr); + + return rc == -1 ? -errno : rc; +} + +/** flic_enqueue_irqs - returns 0 on success + * @buf: pointer to buffer which is passed to kernel + * @len: length of buffer + * @flic: pointer to flic device state + * + * Returns: -EINVAL if attr.group is unknown + */ +static int flic_enqueue_irqs(void *buf, uint64_t len, + KVMS390FLICState *flic) +{ + int rc; + struct kvm_device_attr attr = { + .group = KVM_DEV_FLIC_ENQUEUE, + .addr = (uint64_t) buf, + .attr = len, + }; + + rc = ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr); + + return rc ? -errno : 0; +} + +/** + * __get_all_irqs - store all pending irqs in buffer + * @flic: pointer to flic device state + * @buf: pointer to pointer to a buffer + * @len: length of buffer + * + * Returns: return value of flic_get_all_irqs + * Note: Retry and increase buffer size until flic_get_all_irqs + * either returns a value >= 0 or a negative error code. + * -ENOMEM is an exception, which means the buffer is too small + * and we should try again. Other negative error codes can be + * -EFAULT and -EINVAL which we ignore at this point + */ +static int __get_all_irqs(KVMS390FLICState *flic, + void **buf, int len) +{ + int r; + + do { + /* returns -ENOMEM if buffer is too small and number + * of queued interrupts on success */ + r = flic_get_all_irqs(flic, *buf, len); + if (r >= 0) { + break; + } + len *= 2; + *buf = g_try_realloc(*buf, len); + if (!buf) { + return -ENOMEM; + } + } while (r == -ENOMEM && len <= KVM_S390_FLIC_MAX_BUFFER); + + return r; +} + +/** + * kvm_flic_save - Save pending floating interrupts + * @f: QEMUFile containing migration state + * @opaque: pointer to flic device state + * + * Note: Pass buf and len to kernel. Start with one page and + * increase until buffer is sufficient or maxium size is + * reached + */ +static void kvm_flic_save(QEMUFile *f, void *opaque) +{ + KVMS390FLICState *flic = opaque; + int len = FLIC_SAVE_INITIAL_SIZE; + void *buf; + int count; + + buf = g_try_malloc0(len); + if (!buf) { + /* Storing FLIC_FAILED into the count field here will cause the + * target system to fail when attempting to load irqs from the + * migration state */ + error_report("flic: couldn't allocate memory"); + qemu_put_be64(f, FLIC_FAILED); + return; + } + + count = __get_all_irqs(flic, &buf, len); + if (count < 0) { + error_report("flic: couldn't retrieve irqs from kernel, rc %d", + count); + /* Storing FLIC_FAILED into the count field here will cause the + * target system to fail when attempting to load irqs from the + * migration state */ + qemu_put_be64(f, FLIC_FAILED); + } else { + qemu_put_be64(f, count); + qemu_put_buffer(f, (uint8_t *) buf, + count * sizeof(struct kvm_s390_irq)); + } + g_free(buf); +} + +/** + * kvm_flic_load - Load pending floating interrupts + * @f: QEMUFile containing migration state + * @opaque: pointer to flic device state + * @version_id: version id for migration + * + * Returns: value of flic_enqueue_irqs, -EINVAL on error + * Note: Do nothing when no interrupts where stored + * in QEMUFile + */ +static int kvm_flic_load(QEMUFile *f, void *opaque, int version_id) +{ + uint64_t len = 0; + uint64_t count = 0; + void *buf = NULL; + int r = 0; + + if (version_id != FLIC_SAVEVM_VERSION) { + r = -EINVAL; + goto out; + } + + count = qemu_get_be64(f); + len = count * sizeof(struct kvm_s390_irq); + if (count == FLIC_FAILED) { + r = -EINVAL; + goto out; + } + if (count == 0) { + r = 0; + goto out; + } + buf = g_try_malloc0(len); + if (!buf) { + r = -ENOMEM; + goto out; + } + + if (qemu_get_buffer(f, (uint8_t *) buf, len) != len) { + r = -EINVAL; + goto out_free; + } + r = flic_enqueue_irqs(buf, len, (struct KVMS390FLICState *) opaque); + +out_free: + g_free(buf); +out: + return r; +} + +static void kvm_s390_flic_realize(DeviceState *dev, Error **errp) +{ + KVMS390FLICState *flic_state = KVM_S390_FLIC(dev); + struct kvm_create_device cd = {0}; + int ret; + + flic_state->fd = -1; + if (!kvm_check_extension(kvm_state, KVM_CAP_DEVICE_CTRL)) { + trace_flic_no_device_api(errno); + return; + } + + cd.type = KVM_DEV_TYPE_FLIC; + ret = kvm_vm_ioctl(kvm_state, KVM_CREATE_DEVICE, &cd); + if (ret < 0) { + trace_flic_create_device(errno); + return; + } + flic_state->fd = cd.fd; + + /* Register savevm handler for floating interrupts */ + register_savevm(NULL, "s390-flic", 0, 1, kvm_flic_save, + kvm_flic_load, (void *) flic_state); +} + +static void kvm_s390_flic_unrealize(DeviceState *dev, Error **errp) +{ + KVMS390FLICState *flic_state = KVM_S390_FLIC(dev); + + unregister_savevm(DEVICE(flic_state), "s390-flic", flic_state); +} + +static void kvm_s390_flic_reset(DeviceState *dev) +{ + KVMS390FLICState *flic = KVM_S390_FLIC(dev); + struct kvm_device_attr attr = { + .group = KVM_DEV_FLIC_CLEAR_IRQS, + }; + int rc = 0; + + if (flic->fd == -1) { + return; + } + + rc = ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr); + if (rc) { + trace_flic_reset_failed(errno); + } +} + +static void kvm_s390_flic_class_init(ObjectClass *oc, void *data) +{ + DeviceClass *dc = DEVICE_CLASS(oc); + + dc->realize = kvm_s390_flic_realize; + dc->unrealize = kvm_s390_flic_unrealize; + dc->reset = kvm_s390_flic_reset; +} + +static const TypeInfo kvm_s390_flic_info = { + .name = TYPE_KVM_S390_FLIC, + .parent = TYPE_SYS_BUS_DEVICE, + .instance_size = sizeof(KVMS390FLICState), + .class_init = kvm_s390_flic_class_init, +}; + +static void kvm_s390_flic_register_types(void) +{ + type_register_static(&kvm_s390_flic_info); +} + +type_init(kvm_s390_flic_register_types) -- cgit v1.2.1