From 02c83209726270ddf9597deabc45e08f6fc3942c Mon Sep 17 00:00:00 2001 From: Avi Kivity Date: Sun, 29 Apr 2007 15:02:17 +0300 Subject: [PATCH] KVM: Don't require explicit indication of completion of mmio or pio It is illegal not to return from a pio or mmio request without completing it, as mmio or pio is an atomic operation. Therefore, we can simplify the userspace interface by avoiding the completion indication. Signed-off-by: Avi Kivity --- drivers/kvm/kvm_main.c | 44 +++++++++++++++++++++--------------------- include/linux/kvm.h | 5 ++--- 2 files changed, 24 insertions(+), 25 deletions(-) diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c index f267dbb52845..c8b8cfa332bb 100644 --- a/drivers/kvm/kvm_main.c +++ b/drivers/kvm/kvm_main.c @@ -1237,8 +1237,10 @@ int emulate_instruction(struct kvm_vcpu *vcpu, kvm_arch_ops->decache_regs(vcpu); kvm_arch_ops->set_rflags(vcpu, emulate_ctxt.eflags); - if (vcpu->mmio_is_write) + if (vcpu->mmio_is_write) { + vcpu->mmio_needed = 0; return EMULATE_DO_MMIO; + } return EMULATE_DONE; } @@ -1692,8 +1694,6 @@ static int complete_pio(struct kvm_vcpu *vcpu) vcpu->regs[VCPU_REGS_RSI] += delta; } - vcpu->run->io_completed = 0; - kvm_arch_ops->decache_regs(vcpu); io->count -= io->cur_count; @@ -1800,25 +1800,25 @@ static int kvm_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run) /* re-sync apic's tpr */ vcpu->cr8 = kvm_run->cr8; - if (kvm_run->io_completed) { - if (vcpu->pio.cur_count) { - r = complete_pio(vcpu); - if (r) - goto out; - } else if (!vcpu->mmio_is_write) { - memcpy(vcpu->mmio_data, kvm_run->mmio.data, 8); - vcpu->mmio_read_completed = 1; - vcpu->mmio_needed = 0; - r = emulate_instruction(vcpu, kvm_run, - vcpu->mmio_fault_cr2, 0); - if (r == EMULATE_DO_MMIO) { - /* - * Read-modify-write. Back to userspace. - */ - kvm_run->exit_reason = KVM_EXIT_MMIO; - r = 0; - goto out; - } + if (vcpu->pio.cur_count) { + r = complete_pio(vcpu); + if (r) + goto out; + } + + if (vcpu->mmio_needed) { + memcpy(vcpu->mmio_data, kvm_run->mmio.data, 8); + vcpu->mmio_read_completed = 1; + vcpu->mmio_needed = 0; + r = emulate_instruction(vcpu, kvm_run, + vcpu->mmio_fault_cr2, 0); + if (r == EMULATE_DO_MMIO) { + /* + * Read-modify-write. Back to userspace. + */ + kvm_run->exit_reason = KVM_EXIT_MMIO; + r = 0; + goto out; } } diff --git a/include/linux/kvm.h b/include/linux/kvm.h index 07bf353eeb6f..738c2f50c774 100644 --- a/include/linux/kvm.h +++ b/include/linux/kvm.h @@ -11,7 +11,7 @@ #include #include -#define KVM_API_VERSION 10 +#define KVM_API_VERSION 11 /* * Architectural interrupt line count, and the size of the bitmap needed @@ -58,9 +58,8 @@ enum kvm_exit_reason { /* for KVM_RUN, returned by mmap(vcpu_fd, offset=0) */ struct kvm_run { /* in */ - __u32 io_completed; /* mmio/pio request completed */ __u8 request_interrupt_window; - __u8 padding1[3]; + __u8 padding1[7]; /* out */ __u32 exit_reason; -- 2.20.1