/* * KVM coalesced MMIO * * Copyright (c) 2008 Bull S.A.S. * Copyright 2009 Red Hat, Inc. and/or its affiliates. * * Author: Laurent Vivier * */ #include #include #include #include #include "coalesced_mmio.h" static inline struct kvm_coalesced_mmio_dev *to_mmio(struct kvm_io_device *dev) { return container_of(dev, struct kvm_coalesced_mmio_dev, dev); } static int coalesced_mmio_in_range(struct kvm_coalesced_mmio_dev *dev, gpa_t addr, int len) { /* is it in a batchable area ? * (addr,len) is fully included in * (zone->addr, zone->size) */ if (len < 0) return 0; if (addr + len < addr) return 0; if (addr < dev->zone.addr) return 0; if (addr + len > dev->zone.addr + dev->zone.size) return 0; return 1; } static int coalesced_mmio_has_room(struct kvm_coalesced_mmio_dev *dev) { struct kvm_coalesced_mmio_ring *ring; unsigned avail; /* Are we able to batch it ? */ /* last is the first free entry * check if we don't meet the first used entry * there is always one unused entry in the buffer */ ring = dev->kvm->coalesced_mmio_ring; avail = (ring->first - ring->last - 1) % KVM_COALESCED_MMIO_MAX; if (avail == 0) { /* full */ return 0; } return 1; } static int coalesced_mmio_write(struct kvm_vcpu *vcpu, struct kvm_io_device *this, gpa_t addr, int len, const void *val) { struct kvm_coalesced_mmio_dev *dev = to_mmio(this); struct kvm_coalesced_mmio_ring *ring = dev->kvm->coalesced_mmio_ring; if (!coalesced_mmio_in_range(dev, addr, len)) return -EOPNOTSUPP; spin_lock(&dev->kvm->ring_lock); if (!coalesced_mmio_has_room(dev)) { spin_unlock(&dev->kvm->ring_lock); return -EOPNOTSUPP; } /* copy data in first free entry of the ring */ ring->coalesced_mmio[ring->last].phys_addr = addr; ring->coalesced_mmio[ring->last].len = len; memcpy(ring->coalesced_mmio[ring->last].data, val, len); smp_wmb(); ring->last = (ring->last + 1) % KVM_COALESCED_MMIO_MAX; spin_unlock(&dev->kvm->ring_lock); return 0; } static void coalesced_mmio_destructor(struct kvm_io_device *this) { struct kvm_coalesced_mmio_dev *dev = to_mmio(this); list_del(&dev->list); kfree(dev); } static const struct kvm_io_device_ops coalesced_mmio_ops = { .write = coalesced_mmio_write, .destructor = coalesced_mmio_destructor, }; int kvm_coalesced_mmio_init(struct kvm *kvm) { struct page *page; int ret; ret = -ENOMEM; page = alloc_page(GFP_KERNEL | __GFP_ZERO); if (!page) goto out_err; ret = 0; kvm->coalesced_mmio_ring = page_address(page); /* * We're using this spinlock to sync access to the coalesced ring. * The list doesn't need it's own lock since device registration and * unregistration should only happen when kvm->slots_lock is held. */ spin_lock_init(&kvm->ring_lock); INIT_LIST_HEAD(&kvm->coalesced_zones); out_err: return ret; } void kvm_coalesced_mmio_free(struct kvm *kvm) { if (kvm->coalesced_mmio_ring) free_page((unsigned long)kvm->coalesced_mmio_ring); } int kvm_vm_ioctl_register_coalesced_mmio(struct kvm *kvm, struct kvm_coalesced_mmio_zone *zone) { int ret; struct kvm_coalesced_mmio_dev *dev; dev = kzalloc(sizeof(struct kvm_coalesced_mmio_dev), GFP_KERNEL); if (!dev) return -ENOMEM; kvm_iodevice_init(&dev->dev, &coalesced_mmio_ops); dev->kvm = kvm; dev->zone = *zone; mutex_lock(&kvm->slots_lock); ret = kvm_io_bus_register_dev(kvm, KVM_MMIO_BUS, zone->addr, zone->size, &dev->dev); if (ret < 0) goto out_free_dev; list_add_tail(&dev->list, &kvm->coalesced_zones); mutex_unlock(&kvm->slots_lock); return 0; out_free_dev: mutex_unlock(&kvm->slots_lock); kfree(dev); return ret; } int kvm_vm_ioctl_unregister_coalesced_mmio(struct kvm *kvm, struct kvm_coalesced_mmio_zone *zone) { struct kvm_coalesced_mmio_dev *dev, *tmp; mutex_lock(&kvm->slots_lock); list_for_each_entry_safe(dev, tmp, &kvm->coalesced_zones, list) if (coalesced_mmio_in_range(dev, zone->addr, zone->size)) { kvm_io_bus_unregister_dev(kvm, KVM_MMIO_BUS, &dev->dev); kvm_iodevice_destructor(&dev->dev); } mutex_unlock(&kvm->slots_lock); return 0; } ption>space:mode:
Diffstat (limited to 'drivers/usb/mtu3/Makefile')