[PATCH 004/104] KVM: In-kernel string pio write support

Avi Kivity
2007-09-17T08:30:46Z

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

Add string pio write support to support some version of Windows.

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_main.c | 48 +++++++++++++++++++++++++++++++++++++-----------
1 files changed, 37 insertions(+), 11 deletions(-)

diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c
index df9c05e..1be510b 100644
--- a/drivers/kvm/kvm_main.c
+++ b/drivers/kvm/kvm_main.c
@@ -1760,18 +1760,35 @@ static int complete_pio(struct kvm_vcpu *vcpu)
return 0;
}

-void kernel_pio(struct kvm_io_device *pio_dev, struct kvm_vcpu *vcpu)
+static void kernel_pio(struct kvm_io_device *pio_dev,
+ struct kvm_vcpu *vcpu,
+ void *pd)
{
/* 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);
+ pd);
else
kvm_iodevice_write(pio_dev, vcpu->pio.port,
vcpu->pio.size,
- vcpu->pio_data);
+ pd);
+}
+
+static void pio_string_write(struct kvm_io_device *pio_dev,
+ struct kvm_vcpu *vcpu)
+{
+ struct kvm_pio_request *io = &vcpu->pio;
+ void *pd = vcpu->pio_data;
+ int i;
+
+ for (i = 0; i < io->cur_count; i++) {
+ kvm_iodevice_write(pio_dev, io->port,
+ io->size,
+ pd);
+ pd += io->size;
+ }
}

int kvm_setup_pio(struct kvm_vcpu *vcpu, struct kvm_run *run, int in,
@@ -1779,7 +1796,7 @@ int kvm_setup_pio(struct kvm_vcpu *vcpu, struct kvm_run *run, int in,
gva_t address, int rep, unsigned port)
{
unsigned now, in_page;
- int i;
+ int i, ret = 0;
int nr_pages = 1;
struct page *page;
struct kvm_io_device *pio_dev;
@@ -1806,15 +1823,12 @@ int kvm_setup_pio(struct kvm_vcpu *vcpu, struct kvm_run *run, int in,
memcpy(vcpu->pio_data, &vcpu->regs[VCPU_REGS_RAX], 4);
kvm_arch_ops->decache_regs(vcpu);
if (pio_dev) {
- kernel_pio(pio_dev, vcpu);
+ kernel_pio(pio_dev, vcpu, vcpu->pio_data);
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);
@@ -1862,9 +1876,21 @@ int kvm_setup_pio(struct kvm_vcpu *vcpu, struct kvm_run *run, int in,
}
}

- if (!vcpu->pio.in)
- return pio_copy_data(vcpu);
- return 0;
+ if (!vcpu->pio.in) {
+ /* string PIO write */
+ ret = pio_copy_data(vcpu);
+ if (ret >= 0 && pio_dev) {
+ pio_string_write(pio_dev, vcpu);
+ complete_pio(vcpu);
+ if (vcpu->pio.count == 0)
+ ret = 1;
+ }
+ } else if (pio_dev)
+ printk(KERN_ERR "no string pio read support yet, "
+ "port %x size %d count %ld\n",
+ port, size, count);
+
+ return ret;
}
EXPORT_SYMBOL_GPL(kvm_setup_pio);