KVM: Portability: Move pio emulation functions to x86.c
This patch moves implementation of the following functions from
kvm_main.c to x86.c:
free_pio_guest_pages, vcpu_find_pio_dev, pio_copy_data, complete_pio,
kernel_pio, pio_string_write, kvm_emulate_pio, kvm_emulate_pio_string
The function inject_gp, which was duplicated by yesterday's patch
series, is removed from kvm_main.c now because it is not needed anymore.
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Acked-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
diff --git a/drivers/kvm/x86.c b/drivers/kvm/x86.c
index fe3733d..f75e7d7 100644
--- a/drivers/kvm/x86.c
+++ b/drivers/kvm/x86.c
@@ -1341,6 +1341,249 @@
}
EXPORT_SYMBOL_GPL(emulate_instruction);
+static void free_pio_guest_pages(struct kvm_vcpu *vcpu)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(vcpu->pio.guest_pages); ++i)
+ if (vcpu->pio.guest_pages[i]) {
+ kvm_release_page(vcpu->pio.guest_pages[i]);
+ vcpu->pio.guest_pages[i] = NULL;
+ }
+}
+
+static int pio_copy_data(struct kvm_vcpu *vcpu)
+{
+ void *p = vcpu->pio_data;
+ void *q;
+ unsigned bytes;
+ int nr_pages = vcpu->pio.guest_pages[1] ? 2 : 1;
+
+ q = vmap(vcpu->pio.guest_pages, nr_pages, VM_READ|VM_WRITE,
+ PAGE_KERNEL);
+ if (!q) {
+ free_pio_guest_pages(vcpu);
+ return -ENOMEM;
+ }
+ q += vcpu->pio.guest_page_offset;
+ bytes = vcpu->pio.size * vcpu->pio.cur_count;
+ if (vcpu->pio.in)
+ memcpy(q, p, bytes);
+ else
+ memcpy(p, q, bytes);
+ q -= vcpu->pio.guest_page_offset;
+ vunmap(q);
+ free_pio_guest_pages(vcpu);
+ return 0;
+}
+
+int complete_pio(struct kvm_vcpu *vcpu)
+{
+ struct kvm_pio_request *io = &vcpu->pio;
+ long delta;
+ int r;
+
+ kvm_x86_ops->cache_regs(vcpu);
+
+ if (!io->string) {
+ if (io->in)
+ memcpy(&vcpu->regs[VCPU_REGS_RAX], vcpu->pio_data,
+ io->size);
+ } else {
+ if (io->in) {
+ r = pio_copy_data(vcpu);
+ if (r) {
+ kvm_x86_ops->cache_regs(vcpu);
+ return r;
+ }
+ }
+
+ delta = 1;
+ if (io->rep) {
+ delta *= io->cur_count;
+ /*
+ * The size of the register should really depend on
+ * current address size.
+ */
+ vcpu->regs[VCPU_REGS_RCX] -= delta;
+ }
+ if (io->down)
+ delta = -delta;
+ delta *= io->size;
+ if (io->in)
+ vcpu->regs[VCPU_REGS_RDI] += delta;
+ else
+ vcpu->regs[VCPU_REGS_RSI] += delta;
+ }
+
+ kvm_x86_ops->decache_regs(vcpu);
+
+ io->count -= io->cur_count;
+ io->cur_count = 0;
+
+ return 0;
+}
+
+static void kernel_pio(struct kvm_io_device *pio_dev,
+ struct kvm_vcpu *vcpu,
+ void *pd)
+{
+ /* TODO: String I/O for in kernel device */
+
+ mutex_lock(&vcpu->kvm->lock);
+ if (vcpu->pio.in)
+ kvm_iodevice_read(pio_dev, vcpu->pio.port,
+ vcpu->pio.size,
+ pd);
+ else
+ kvm_iodevice_write(pio_dev, vcpu->pio.port,
+ vcpu->pio.size,
+ pd);
+ mutex_unlock(&vcpu->kvm->lock);
+}
+
+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;
+
+ mutex_lock(&vcpu->kvm->lock);
+ for (i = 0; i < io->cur_count; i++) {
+ kvm_iodevice_write(pio_dev, io->port,
+ io->size,
+ pd);
+ pd += io->size;
+ }
+ mutex_unlock(&vcpu->kvm->lock);
+}
+
+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);
+}
+
+int kvm_emulate_pio(struct kvm_vcpu *vcpu, struct kvm_run *run, int in,
+ int size, unsigned port)
+{
+ 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;
+ vcpu->run->io.size = vcpu->pio.size = size;
+ vcpu->run->io.data_offset = KVM_PIO_PAGE_OFFSET * PAGE_SIZE;
+ vcpu->run->io.count = vcpu->pio.count = vcpu->pio.cur_count = 1;
+ vcpu->run->io.port = vcpu->pio.port = port;
+ vcpu->pio.in = in;
+ vcpu->pio.string = 0;
+ vcpu->pio.down = 0;
+ vcpu->pio.guest_page_offset = 0;
+ vcpu->pio.rep = 0;
+
+ kvm_x86_ops->cache_regs(vcpu);
+ memcpy(vcpu->pio_data, &vcpu->regs[VCPU_REGS_RAX], 4);
+ kvm_x86_ops->decache_regs(vcpu);
+
+ kvm_x86_ops->skip_emulated_instruction(vcpu);
+
+ pio_dev = vcpu_find_pio_dev(vcpu, port);
+ if (pio_dev) {
+ kernel_pio(pio_dev, vcpu, vcpu->pio_data);
+ complete_pio(vcpu);
+ return 1;
+ }
+ return 0;
+}
+EXPORT_SYMBOL_GPL(kvm_emulate_pio);
+
+int kvm_emulate_pio_string(struct kvm_vcpu *vcpu, struct kvm_run *run, int in,
+ int size, unsigned long count, int down,
+ gva_t address, int rep, unsigned port)
+{
+ unsigned now, in_page;
+ int i, ret = 0;
+ 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;
+ vcpu->run->io.size = vcpu->pio.size = size;
+ vcpu->run->io.data_offset = KVM_PIO_PAGE_OFFSET * PAGE_SIZE;
+ vcpu->run->io.count = vcpu->pio.count = vcpu->pio.cur_count = count;
+ vcpu->run->io.port = vcpu->pio.port = port;
+ vcpu->pio.in = in;
+ vcpu->pio.string = 1;
+ vcpu->pio.down = down;
+ vcpu->pio.guest_page_offset = offset_in_page(address);
+ vcpu->pio.rep = rep;
+
+ if (!count) {
+ kvm_x86_ops->skip_emulated_instruction(vcpu);
+ return 1;
+ }
+
+ if (!down)
+ in_page = PAGE_SIZE - offset_in_page(address);
+ else
+ in_page = offset_in_page(address) + size;
+ now = min(count, (unsigned long)in_page / size);
+ if (!now) {
+ /*
+ * String I/O straddles page boundary. Pin two guest pages
+ * so that we satisfy atomicity constraints. Do just one
+ * transaction to avoid complexity.
+ */
+ nr_pages = 2;
+ now = 1;
+ }
+ if (down) {
+ /*
+ * String I/O in reverse. Yuck. Kill the guest, fix later.
+ */
+ pr_unimpl(vcpu, "guest string pio down\n");
+ inject_gp(vcpu);
+ return 1;
+ }
+ vcpu->run->io.count = now;
+ vcpu->pio.cur_count = now;
+
+ if (vcpu->pio.cur_count == vcpu->pio.count)
+ kvm_x86_ops->skip_emulated_instruction(vcpu);
+
+ for (i = 0; i < nr_pages; ++i) {
+ mutex_lock(&vcpu->kvm->lock);
+ page = gva_to_page(vcpu, address + i * PAGE_SIZE);
+ vcpu->pio.guest_pages[i] = page;
+ mutex_unlock(&vcpu->kvm->lock);
+ if (!page) {
+ inject_gp(vcpu);
+ free_pio_guest_pages(vcpu);
+ return 1;
+ }
+ }
+
+ pio_dev = vcpu_find_pio_dev(vcpu, port);
+ 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)
+ pr_unimpl(vcpu, "no string pio read support yet, "
+ "port %x size %d count %ld\n",
+ port, size, count);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(kvm_emulate_pio_string);
+
__init void kvm_arch_init(void)
{
kvm_init_msr_list();