From 45e96ea6b369539a37040a8df9c59a39f073d9d6 Mon Sep 17 00:00:00 2001 From: Christoffer Dall Date: Sun, 20 Jan 2013 18:43:58 -0500 Subject: KVM: ARM: Handle I/O aborts When the guest accesses I/O memory this will create data abort exceptions and they are handled by decoding the HSR information (physical address, read/write, length, register) and forwarding reads and writes to QEMU which performs the device emulation. Certain classes of load/store operations do not support the syndrome information provided in the HSR. We don't support decoding these (patches are available elsewhere), so we report an error to user space in this case. This requires changing the general flow somewhat since new calls to run the VCPU must check if there's a pending MMIO load and perform the write after userspace has made the data available. Reviewed-by: Will Deacon Reviewed-by: Marcelo Tosatti Signed-off-by: Rusty Russell Signed-off-by: Marc Zyngier Signed-off-by: Christoffer Dall --- arch/arm/include/asm/kvm_mmio.h | 56 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 56 insertions(+) create mode 100644 arch/arm/include/asm/kvm_mmio.h (limited to 'arch/arm/include/asm/kvm_mmio.h') diff --git a/arch/arm/include/asm/kvm_mmio.h b/arch/arm/include/asm/kvm_mmio.h new file mode 100644 index 0000000..adcc0d7 --- /dev/null +++ b/arch/arm/include/asm/kvm_mmio.h @@ -0,0 +1,56 @@ +/* + * Copyright (C) 2012 - Virtual Open Systems and Columbia University + * Author: Christoffer Dall + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License, version 2, as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + */ + +#ifndef __ARM_KVM_MMIO_H__ +#define __ARM_KVM_MMIO_H__ + +#include +#include +#include + +struct kvm_decode { + unsigned long rt; + bool sign_extend; +}; + +/* + * The in-kernel MMIO emulation code wants to use a copy of run->mmio, + * which is an anonymous type. Use our own type instead. + */ +struct kvm_exit_mmio { + phys_addr_t phys_addr; + u8 data[8]; + u32 len; + bool is_write; +}; + +static inline void kvm_prepare_mmio(struct kvm_run *run, + struct kvm_exit_mmio *mmio) +{ + run->mmio.phys_addr = mmio->phys_addr; + run->mmio.len = mmio->len; + run->mmio.is_write = mmio->is_write; + memcpy(run->mmio.data, mmio->data, mmio->len); + run->exit_reason = KVM_EXIT_MMIO; +} + +int kvm_handle_mmio_return(struct kvm_vcpu *vcpu, struct kvm_run *run); +int io_mem_abort(struct kvm_vcpu *vcpu, struct kvm_run *run, + phys_addr_t fault_ipa); + +#endif /* __ARM_KVM_MMIO_H__ */ -- cgit v1.1