[PATCH 05/20] KVM: Add support for in-kernel pio handlers

Avi Kivity
2007-07-08T11:54:34Z

From: Eddie Dong <eddie.dong-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>

Useful for the PIC and PIT.

Signed-off-by: Yaozu (Eddie) Dong <eddie.dong-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Signed-off-by: Avi Kivity <avi-atKUWr5tajBWk0Htik3J/w@public.gmane.org>
---
drivers/kvm/kvm.h | 5 ++++-
drivers/kvm/kvm_main.c | 33 +++++++++++++++++++++++++++++++++
2 files changed, 37 insertions(+), 1 deletions(-)

diff --git a/drivers/kvm/kvm.h b/drivers/kvm/kvm.h
index 31846b1..a7c5e6b 100644
--- a/drivers/kvm/kvm.h
+++ b/drivers/kvm/kvm.h
@@ -241,6 +241,7 @@ struct kvm_pio_request {
struct page *guest_pages[2];
unsigned guest_page_offset;
int in;
+ int port;
int size;
int string;
int down;
@@ -303,7 +304,8 @@ static inline int kvm_iodevice_inrange(struct kvm_io_device *dev, gpa_t addr)

static inline void kvm_iodevice_destructor(struct kvm_io_device *dev)
{
- dev->destructor(dev);
+ if (dev->destructor)
+ dev->destructor(dev);
}

/*
@@ -453,6 +455,7 @@ struct kvm {
struct list_head vm_list;
struct file *filp;
struct kvm_io_bus mmio_bus;
+ struct kvm_io_bus pio_bus;
};

struct descriptor_table {
diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c
index e157e28..7826f16 100644
--- a/drivers/kvm/kvm_main.c
+++ b/drivers/kvm/kvm_main.c
@@ -361,6 +361,7 @@ static struct kvm *kvm_create_vm(void)
if (!kvm)
return ERR_PTR(-ENOMEM);

+ kvm_io_bus_init(&kvm->pio_bus);
spin_lock_init(&kvm->lock);
INIT_LIST_HEAD(&kvm->active_mmu_pages);
spin_lock(&kvm_lock);
@@ -475,6 +476,7 @@ static void kvm_destroy_vm(struct kvm *kvm)
spin_lock(&kvm_lock);
list_del(&kvm->vm_list);
spin_unlock(&kvm_lock);
+ kvm_io_bus_destroy(&kvm->pio_bus);
kvm_io_bus_destroy(&kvm->mmio_bus);
kvm_free_vcpus(kvm);
kvm_free_physmem(kvm);
@@ -1110,6 +1112,12 @@ static struct kvm_io_device *vcpu_find_mmio_dev(struct kvm_vcpu *vcpu,
return kvm_io_bus_find_dev(&vcpu->kvm->mmio_bus, addr);
}

+static struct kvm_io_device *vcpu_find_pio_dev(struct kvm_vcpu *vcpu,
+ gpa_t addr)
+{
+ return kvm_io_bus_find_dev(&vcpu->kvm->pio_bus, addr);
+}
+
static int emulator_read_emulated(unsigned long addr,
void *val,
unsigned int bytes,
@@ -1832,6 +1840,20 @@ static int complete_pio(struct kvm_vcpu *vcpu)
return 0;
}

+void kernel_pio(struct kvm_io_device *pio_dev, struct kvm_vcpu *vcpu)
+{
+ /* TODO: String I/O for in kernel device */
+
+ if (vcpu->pio.in)
+ kvm_iodevice_read(pio_dev, vcpu->pio.port,
+ vcpu->pio.size,
+ vcpu->pio_data);
+ else
+ kvm_iodevice_write(pio_dev, vcpu->pio.port,
+ vcpu->pio.size,
+ vcpu->pio_data);
+}
+
int kvm_setup_pio(struct kvm_vcpu *vcpu, struct kvm_run *run, int in,
int size, unsigned long count, int string, int down,
gva_t address, int rep, unsigned port)
@@ -1840,6 +1862,7 @@ int kvm_setup_pio(struct kvm_vcpu *vcpu, struct kvm_run *run, int in,
int i;
int nr_pages = 1;
struct page *page;
+ struct kvm_io_device *pio_dev;

vcpu->run->exit_reason = KVM_EXIT_IO;
vcpu->run->io.direction = in ? KVM_EXIT_IO_IN : KVM_EXIT_IO_OUT;
@@ -1851,17 +1874,27 @@ int kvm_setup_pio(struct kvm_vcpu *vcpu, struct kvm_run *run, int in,
vcpu->pio.cur_count = count;
vcpu->pio.size = size;
vcpu->pio.in = in;
+ vcpu->pio.port = port;
vcpu->pio.string = string;
vcpu->pio.down = down;
vcpu->pio.guest_page_offset = offset_in_page(address);
vcpu->pio.rep = rep;

+ pio_dev = vcpu_find_pio_dev(vcpu, port);
if (!string) {
kvm_arch_ops->cache_regs(vcpu);
memcpy(vcpu->pio_data, &vcpu->regs[VCPU_REGS_RAX], 4);
kvm_arch_ops->decache_regs(vcpu);
+ if (pio_dev) {
+ kernel_pio(pio_dev, vcpu);
+ complete_pio(vcpu);
+ return 1;
+ }
return 0;
}
+ /* TODO: String I/O for in kernel device */
+ if (pio_dev)
+ printk(KERN_ERR "kvm_setup_pio: no string io support\n");

if (!count) {
kvm_arch_ops->skip_emulated_instruction(vcpu);