KVM: convert io_bus to SRCU

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
This commit is contained in:
Marcelo Tosatti 2009-12-23 14:35:24 -02:00
parent a983fb2387
commit e93f8a0f82
9 changed files with 101 additions and 75 deletions

View File

@ -241,10 +241,10 @@ static int handle_mmio(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
return 0;
mmio:
if (p->dir)
r = kvm_io_bus_read(&vcpu->kvm->mmio_bus, p->addr,
r = kvm_io_bus_read(vcpu->kvm, KVM_MMIO_BUS, p->addr,
p->size, &p->data);
else
r = kvm_io_bus_write(&vcpu->kvm->mmio_bus, p->addr,
r = kvm_io_bus_write(vcpu->kvm, KVM_MMIO_BUS, p->addr,
p->size, &p->data);
if (r)
printk(KERN_ERR"kvm: No iodevice found! addr:%lx\n", p->addr);

View File

@ -645,13 +645,13 @@ struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags)
kvm_register_irq_mask_notifier(kvm, 0, &pit->mask_notifier);
kvm_iodevice_init(&pit->dev, &pit_dev_ops);
ret = __kvm_io_bus_register_dev(&kvm->pio_bus, &pit->dev);
ret = kvm_io_bus_register_dev(kvm, KVM_PIO_BUS, &pit->dev);
if (ret < 0)
goto fail;
if (flags & KVM_PIT_SPEAKER_DUMMY) {
kvm_iodevice_init(&pit->speaker_dev, &speaker_dev_ops);
ret = __kvm_io_bus_register_dev(&kvm->pio_bus,
ret = kvm_io_bus_register_dev(kvm, KVM_PIO_BUS,
&pit->speaker_dev);
if (ret < 0)
goto fail_unregister;
@ -660,7 +660,7 @@ struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags)
return pit;
fail_unregister:
__kvm_io_bus_unregister_dev(&kvm->pio_bus, &pit->dev);
kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, &pit->dev);
fail:
if (pit->irq_source_id >= 0)

View File

@ -533,7 +533,9 @@ struct kvm_pic *kvm_create_pic(struct kvm *kvm)
* Initialize PIO device
*/
kvm_iodevice_init(&s->dev, &picdev_ops);
ret = kvm_io_bus_register_dev(kvm, &kvm->pio_bus, &s->dev);
down_write(&kvm->slots_lock);
ret = kvm_io_bus_register_dev(kvm, KVM_PIO_BUS, &s->dev);
up_write(&kvm->slots_lock);
if (ret < 0) {
kfree(s);
return NULL;

View File

@ -2851,7 +2851,7 @@ static int vcpu_mmio_write(struct kvm_vcpu *vcpu, gpa_t addr, int len,
!kvm_iodevice_write(&vcpu->arch.apic->dev, addr, len, v))
return 0;
return kvm_io_bus_write(&vcpu->kvm->mmio_bus, addr, len, v);
return kvm_io_bus_write(vcpu->kvm, KVM_MMIO_BUS, addr, len, v);
}
static int vcpu_mmio_read(struct kvm_vcpu *vcpu, gpa_t addr, int len, void *v)
@ -2860,7 +2860,7 @@ static int vcpu_mmio_read(struct kvm_vcpu *vcpu, gpa_t addr, int len, void *v)
!kvm_iodevice_read(&vcpu->arch.apic->dev, addr, len, v))
return 0;
return kvm_io_bus_read(&vcpu->kvm->mmio_bus, addr, len, v);
return kvm_io_bus_read(vcpu->kvm, KVM_MMIO_BUS, addr, len, v);
}
static int kvm_read_guest_virt(gva_t addr, void *val, unsigned int bytes,
@ -3345,11 +3345,12 @@ static int kernel_pio(struct kvm_vcpu *vcpu, void *pd)
int r;
if (vcpu->arch.pio.in)
r = kvm_io_bus_read(&vcpu->kvm->pio_bus, vcpu->arch.pio.port,
r = kvm_io_bus_read(vcpu->kvm, KVM_PIO_BUS, vcpu->arch.pio.port,
vcpu->arch.pio.size, pd);
else
r = kvm_io_bus_write(&vcpu->kvm->pio_bus, vcpu->arch.pio.port,
vcpu->arch.pio.size, pd);
r = kvm_io_bus_write(vcpu->kvm, KVM_PIO_BUS,
vcpu->arch.pio.port, vcpu->arch.pio.size,
pd);
return r;
}
@ -3360,7 +3361,7 @@ static int pio_string_write(struct kvm_vcpu *vcpu)
int i, r = 0;
for (i = 0; i < io->cur_count; i++) {
if (kvm_io_bus_write(&vcpu->kvm->pio_bus,
if (kvm_io_bus_write(vcpu->kvm, KVM_PIO_BUS,
io->port, io->size, pd)) {
r = -EOPNOTSUPP;
break;

View File

@ -57,20 +57,20 @@ struct kvm_io_bus {
struct kvm_io_device *devs[NR_IOBUS_DEVS];
};
void kvm_io_bus_init(struct kvm_io_bus *bus);
void kvm_io_bus_destroy(struct kvm_io_bus *bus);
int kvm_io_bus_write(struct kvm_io_bus *bus, gpa_t addr, int len,
const void *val);
int kvm_io_bus_read(struct kvm_io_bus *bus, gpa_t addr, int len,
enum kvm_bus {
KVM_MMIO_BUS,
KVM_PIO_BUS,
KVM_NR_BUSES
};
int kvm_io_bus_write(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
int len, const void *val);
int kvm_io_bus_read(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr, int len,
void *val);
int __kvm_io_bus_register_dev(struct kvm_io_bus *bus,
struct kvm_io_device *dev);
int kvm_io_bus_register_dev(struct kvm *kvm, struct kvm_io_bus *bus,
int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx,
struct kvm_io_device *dev);
void __kvm_io_bus_unregister_dev(struct kvm_io_bus *bus,
struct kvm_io_device *dev);
void kvm_io_bus_unregister_dev(struct kvm *kvm, struct kvm_io_bus *bus,
struct kvm_io_device *dev);
int kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx,
struct kvm_io_device *dev);
struct kvm_vcpu {
struct kvm *kvm;
@ -171,8 +171,7 @@ struct kvm {
atomic_t online_vcpus;
struct list_head vm_list;
struct mutex lock;
struct kvm_io_bus mmio_bus;
struct kvm_io_bus pio_bus;
struct kvm_io_bus *buses[KVM_NR_BUSES];
#ifdef CONFIG_HAVE_KVM_EVENTFD
struct {
spinlock_t lock;

View File

@ -110,7 +110,9 @@ int kvm_coalesced_mmio_init(struct kvm *kvm)
dev->kvm = kvm;
kvm->coalesced_mmio_dev = dev;
ret = kvm_io_bus_register_dev(kvm, &kvm->mmio_bus, &dev->dev);
down_write(&kvm->slots_lock);
ret = kvm_io_bus_register_dev(kvm, KVM_MMIO_BUS, &dev->dev);
up_write(&kvm->slots_lock);
if (ret < 0)
goto out_free_dev;

View File

@ -463,7 +463,7 @@ static int
kvm_assign_ioeventfd(struct kvm *kvm, struct kvm_ioeventfd *args)
{
int pio = args->flags & KVM_IOEVENTFD_FLAG_PIO;
struct kvm_io_bus *bus = pio ? &kvm->pio_bus : &kvm->mmio_bus;
enum kvm_bus bus_idx = pio ? KVM_PIO_BUS : KVM_MMIO_BUS;
struct _ioeventfd *p;
struct eventfd_ctx *eventfd;
int ret;
@ -518,7 +518,7 @@ kvm_assign_ioeventfd(struct kvm *kvm, struct kvm_ioeventfd *args)
kvm_iodevice_init(&p->dev, &ioeventfd_ops);
ret = __kvm_io_bus_register_dev(bus, &p->dev);
ret = kvm_io_bus_register_dev(kvm, bus_idx, &p->dev);
if (ret < 0)
goto unlock_fail;
@ -542,7 +542,7 @@ static int
kvm_deassign_ioeventfd(struct kvm *kvm, struct kvm_ioeventfd *args)
{
int pio = args->flags & KVM_IOEVENTFD_FLAG_PIO;
struct kvm_io_bus *bus = pio ? &kvm->pio_bus : &kvm->mmio_bus;
enum kvm_bus bus_idx = pio ? KVM_PIO_BUS : KVM_MMIO_BUS;
struct _ioeventfd *p, *tmp;
struct eventfd_ctx *eventfd;
int ret = -ENOENT;
@ -565,7 +565,7 @@ kvm_deassign_ioeventfd(struct kvm *kvm, struct kvm_ioeventfd *args)
if (!p->wildcard && p->datamatch != args->datamatch)
continue;
__kvm_io_bus_unregister_dev(bus, &p->dev);
kvm_io_bus_unregister_dev(kvm, bus_idx, &p->dev);
ioeventfd_release(p);
ret = 0;
break;

View File

@ -372,7 +372,9 @@ int kvm_ioapic_init(struct kvm *kvm)
kvm_ioapic_reset(ioapic);
kvm_iodevice_init(&ioapic->dev, &ioapic_mmio_ops);
ioapic->kvm = kvm;
ret = kvm_io_bus_register_dev(kvm, &kvm->mmio_bus, &ioapic->dev);
down_write(&kvm->slots_lock);
ret = kvm_io_bus_register_dev(kvm, KVM_MMIO_BUS, &ioapic->dev);
up_write(&kvm->slots_lock);
if (ret < 0)
kfree(ioapic);

View File

@ -85,6 +85,8 @@ static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
static int hardware_enable_all(void);
static void hardware_disable_all(void);
static void kvm_io_bus_destroy(struct kvm_io_bus *bus);
static bool kvm_rebooting;
static bool largepages_enabled = true;
@ -367,7 +369,7 @@ static int kvm_init_mmu_notifier(struct kvm *kvm)
static struct kvm *kvm_create_vm(void)
{
int r = 0;
int r = 0, i;
struct kvm *kvm = kvm_arch_create_vm();
#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
struct page *page;
@ -391,6 +393,14 @@ static struct kvm *kvm_create_vm(void)
goto out_err;
if (init_srcu_struct(&kvm->srcu))
goto out_err;
for (i = 0; i < KVM_NR_BUSES; i++) {
kvm->buses[i] = kzalloc(sizeof(struct kvm_io_bus),
GFP_KERNEL);
if (!kvm->buses[i]) {
cleanup_srcu_struct(&kvm->srcu);
goto out_err;
}
}
#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
page = alloc_page(GFP_KERNEL | __GFP_ZERO);
@ -416,11 +426,9 @@ static struct kvm *kvm_create_vm(void)
atomic_inc(&kvm->mm->mm_count);
spin_lock_init(&kvm->mmu_lock);
spin_lock_init(&kvm->requests_lock);
kvm_io_bus_init(&kvm->pio_bus);
kvm_eventfd_init(kvm);
mutex_init(&kvm->lock);
mutex_init(&kvm->irq_lock);
kvm_io_bus_init(&kvm->mmio_bus);
init_rwsem(&kvm->slots_lock);
atomic_set(&kvm->users_count, 1);
spin_lock(&kvm_lock);
@ -435,6 +443,8 @@ out:
out_err:
hardware_disable_all();
out_err_nodisable:
for (i = 0; i < KVM_NR_BUSES; i++)
kfree(kvm->buses[i]);
kfree(kvm->memslots);
kfree(kvm);
return ERR_PTR(r);
@ -480,6 +490,7 @@ void kvm_free_physmem(struct kvm *kvm)
static void kvm_destroy_vm(struct kvm *kvm)
{
int i;
struct mm_struct *mm = kvm->mm;
kvm_arch_sync_events(kvm);
@ -487,8 +498,8 @@ static void kvm_destroy_vm(struct kvm *kvm)
list_del(&kvm->vm_list);
spin_unlock(&kvm_lock);
kvm_free_irq_routing(kvm);
kvm_io_bus_destroy(&kvm->pio_bus);
kvm_io_bus_destroy(&kvm->mmio_bus);
for (i = 0; i < KVM_NR_BUSES; i++)
kvm_io_bus_destroy(kvm->buses[i]);
kvm_coalesced_mmio_free(kvm);
#if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
mmu_notifier_unregister(&kvm->mmu_notifier, kvm->mm);
@ -1949,12 +1960,7 @@ static struct notifier_block kvm_reboot_notifier = {
.priority = 0,
};
void kvm_io_bus_init(struct kvm_io_bus *bus)
{
memset(bus, 0, sizeof(*bus));
}
void kvm_io_bus_destroy(struct kvm_io_bus *bus)
static void kvm_io_bus_destroy(struct kvm_io_bus *bus)
{
int i;
@ -1963,13 +1969,15 @@ void kvm_io_bus_destroy(struct kvm_io_bus *bus)
kvm_iodevice_destructor(pos);
}
kfree(bus);
}
/* kvm_io_bus_write - called under kvm->slots_lock */
int kvm_io_bus_write(struct kvm_io_bus *bus, gpa_t addr,
int kvm_io_bus_write(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
int len, const void *val)
{
int i;
struct kvm_io_bus *bus = rcu_dereference(kvm->buses[bus_idx]);
for (i = 0; i < bus->dev_count; i++)
if (!kvm_iodevice_write(bus->devs[i], addr, len, val))
return 0;
@ -1977,59 +1985,71 @@ int kvm_io_bus_write(struct kvm_io_bus *bus, gpa_t addr,
}
/* kvm_io_bus_read - called under kvm->slots_lock */
int kvm_io_bus_read(struct kvm_io_bus *bus, gpa_t addr, int len, void *val)
int kvm_io_bus_read(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
int len, void *val)
{
int i;
struct kvm_io_bus *bus = rcu_dereference(kvm->buses[bus_idx]);
for (i = 0; i < bus->dev_count; i++)
if (!kvm_iodevice_read(bus->devs[i], addr, len, val))
return 0;
return -EOPNOTSUPP;
}
int kvm_io_bus_register_dev(struct kvm *kvm, struct kvm_io_bus *bus,
struct kvm_io_device *dev)
/* Caller must have write lock on slots_lock. */
int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx,
struct kvm_io_device *dev)
{
int ret;
struct kvm_io_bus *new_bus, *bus;
down_write(&kvm->slots_lock);
ret = __kvm_io_bus_register_dev(bus, dev);
up_write(&kvm->slots_lock);
return ret;
}
/* An unlocked version. Caller must have write lock on slots_lock. */
int __kvm_io_bus_register_dev(struct kvm_io_bus *bus,
struct kvm_io_device *dev)
{
bus = kvm->buses[bus_idx];
if (bus->dev_count > NR_IOBUS_DEVS-1)
return -ENOSPC;
bus->devs[bus->dev_count++] = dev;
new_bus = kzalloc(sizeof(struct kvm_io_bus), GFP_KERNEL);
if (!new_bus)
return -ENOMEM;
memcpy(new_bus, bus, sizeof(struct kvm_io_bus));
new_bus->devs[new_bus->dev_count++] = dev;
rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
synchronize_srcu_expedited(&kvm->srcu);
kfree(bus);
return 0;
}
void kvm_io_bus_unregister_dev(struct kvm *kvm,
struct kvm_io_bus *bus,
struct kvm_io_device *dev)
/* Caller must have write lock on slots_lock. */
int kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx,
struct kvm_io_device *dev)
{
down_write(&kvm->slots_lock);
__kvm_io_bus_unregister_dev(bus, dev);
up_write(&kvm->slots_lock);
}
int i, r;
struct kvm_io_bus *new_bus, *bus;
/* An unlocked version. Caller must have write lock on slots_lock. */
void __kvm_io_bus_unregister_dev(struct kvm_io_bus *bus,
struct kvm_io_device *dev)
{
int i;
new_bus = kzalloc(sizeof(struct kvm_io_bus), GFP_KERNEL);
if (!new_bus)
return -ENOMEM;
for (i = 0; i < bus->dev_count; i++)
if (bus->devs[i] == dev) {
bus->devs[i] = bus->devs[--bus->dev_count];
bus = kvm->buses[bus_idx];
memcpy(new_bus, bus, sizeof(struct kvm_io_bus));
r = -ENOENT;
for (i = 0; i < new_bus->dev_count; i++)
if (new_bus->devs[i] == dev) {
r = 0;
new_bus->devs[i] = new_bus->devs[--new_bus->dev_count];
break;
}
if (r) {
kfree(new_bus);
return r;
}
rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
synchronize_srcu_expedited(&kvm->srcu);
kfree(bus);
return r;
}
static struct notifier_block kvm_cpu_notifier = {