diff options
| author | Avi Kivity <avi@redhat.com> | 2010-01-20 12:01:20 +0200 |
|---|---|---|
| committer | Avi Kivity <avi@redhat.com> | 2011-05-11 07:56:58 -0400 |
| commit | cef4dea07f6720b36cc93e18a2e68be4bdb71a92 (patch) | |
| tree | f6c67df1a54a2770d23086446807ca62f964c2e1 /arch | |
| parent | 5287f194bf0d7062d6d99b725366202556f03e28 (diff) | |
KVM: 16-byte mmio support
Since sse instructions can issue 16-byte mmios, we need to support them. We
can't increase the kvm_run mmio buffer size to 16 bytes without breaking
compatibility, so instead we break the large mmios into two smaller 8-byte
ones. Since the bus is 64-bit we aren't breaking any atomicity guarantees.
Signed-off-by: Avi Kivity <avi@redhat.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/include/asm/kvm_host.h | 1 | ||||
| -rw-r--r-- | arch/x86/kvm/x86.c | 34 |
2 files changed, 26 insertions, 9 deletions
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 35f81b11026..e820c6339b8 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -30,6 +30,7 @@ #define KVM_MEMORY_SLOTS 32 /* memory slots that does not exposed to userspace */ #define KVM_PRIVATE_MEM_SLOTS 4 +#define KVM_MMIO_SIZE 16 #define KVM_PIO_PAGE_OFFSET 1 #define KVM_COALESCED_MMIO_PAGE_OFFSET 2 diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index bb6b9d3f5e9..11d692c7018 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -3833,8 +3833,10 @@ mmio: vcpu->mmio_needed = 1; vcpu->run->exit_reason = KVM_EXIT_MMIO; vcpu->run->mmio.phys_addr = vcpu->mmio_phys_addr = gpa; - vcpu->run->mmio.len = vcpu->mmio_size = bytes; + vcpu->mmio_size = bytes; + vcpu->run->mmio.len = min(vcpu->mmio_size, 8); vcpu->run->mmio.is_write = vcpu->mmio_is_write = 0; + vcpu->mmio_index = 0; return X86EMUL_IO_NEEDED; } @@ -3886,11 +3888,14 @@ mmio: val += handled; vcpu->mmio_needed = 1; + memcpy(vcpu->mmio_data, val, bytes); vcpu->run->exit_reason = KVM_EXIT_MMIO; vcpu->run->mmio.phys_addr = vcpu->mmio_phys_addr = gpa; - vcpu->run->mmio.len = vcpu->mmio_size = bytes; + vcpu->mmio_size = bytes; + vcpu->run->mmio.len = min(vcpu->mmio_size, 8); vcpu->run->mmio.is_write = vcpu->mmio_is_write = 1; - memcpy(vcpu->run->mmio.data, val, bytes); + memcpy(vcpu->run->mmio.data, vcpu->mmio_data, 8); + vcpu->mmio_index = 0; return X86EMUL_CONTINUE; } @@ -4498,11 +4503,9 @@ restart: if (!vcpu->arch.pio.in) vcpu->arch.pio.count = 0; r = EMULATE_DO_MMIO; - } else if (vcpu->mmio_needed) { - if (vcpu->mmio_is_write) - vcpu->mmio_needed = 0; + } else if (vcpu->mmio_needed) r = EMULATE_DO_MMIO; - } else if (r == EMULATION_RESTART) + else if (r == EMULATION_RESTART) goto restart; else r = EMULATE_DONE; @@ -5450,9 +5453,22 @@ static int complete_mmio(struct kvm_vcpu *vcpu) return 1; if (vcpu->mmio_needed) { - memcpy(vcpu->mmio_data, run->mmio.data, 8); - vcpu->mmio_read_completed = 1; vcpu->mmio_needed = 0; + if (!vcpu->mmio_is_write) + memcpy(vcpu->mmio_data, run->mmio.data, 8); + vcpu->mmio_index += 8; + if (vcpu->mmio_index < vcpu->mmio_size) { + run->exit_reason = KVM_EXIT_MMIO; + run->mmio.phys_addr = vcpu->mmio_phys_addr + vcpu->mmio_index; + memcpy(run->mmio.data, vcpu->mmio_data + vcpu->mmio_index, 8); + run->mmio.len = min(vcpu->mmio_size - vcpu->mmio_index, 8); + run->mmio.is_write = vcpu->mmio_is_write; + vcpu->mmio_needed = 1; + return 0; + } + if (vcpu->mmio_is_write) + return 1; + vcpu->mmio_read_completed = 1; } vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu); r = emulate_instruction(vcpu, EMULTYPE_NO_DECODE); |