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original_kernel/arch/mips/kvm/commpage.c

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KVM/MIPS32: Binary patching of select privileged instructions. Currently, the following instructions are translated: - CACHE (indexed) - CACHE (va based): translated to a SYNCI, overkill on D-CACHE operations, but still much faster than a trap. - mfc0/mtc0: the virtual COP0 registers for the guest are implemented as 2-D array. [COP#][SEL] and this is mapped into the guest kernel address space @ VA 0x0. mfc0/mtc0 operations are transformed to load/stores. Signed-off-by: Sanjay Lal <sanjayl@kymasys.com> Cc: kvm@vger.kernel.org Cc: linux-mips@linux-mips.org Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2012-11-22 10:34:16 +08:00
/*
MIPS: KVM: Reformat code and comments No logic changes inside. Signed-off-by: Deng-Cheng Zhu <dengcheng.zhu@imgtec.com> Reviewed-by: James Hogan <james.hogan@imgtec.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-06-27 03:11:34 +08:00
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* commpage, currently used for Virtual COP0 registers.
MIPS: KVM: Move commpage so 0x0 is unmapped The comm page which is mapped into the guest kernel address space at 0x0 has the unfortunate side effect of allowing guest kernel NULL pointer dereferences to succeed. The only constraint on this address is that it must be within 32KiB of 0x0, so that single lw/sw instructions (which have 16-bit signed offset fields) can be used to access it, using the zero register as a base. So lets move the comm page as high as possible within that constraint so that 0x0 can be left unmapped, at least for page sizes < 32KiB. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-16 02:29:57 +08:00
* Mapped into the guest kernel @ KVM_GUEST_COMMPAGE_ADDR.
MIPS: KVM: Reformat code and comments No logic changes inside. Signed-off-by: Deng-Cheng Zhu <dengcheng.zhu@imgtec.com> Reviewed-by: James Hogan <james.hogan@imgtec.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-06-27 03:11:34 +08:00
*
* Copyright (C) 2012 MIPS Technologies, Inc. All rights reserved.
* Authors: Sanjay Lal <sanjayl@kymasys.com>
*/
KVM/MIPS32: Binary patching of select privileged instructions. Currently, the following instructions are translated: - CACHE (indexed) - CACHE (va based): translated to a SYNCI, overkill on D-CACHE operations, but still much faster than a trap. - mfc0/mtc0: the virtual COP0 registers for the guest are implemented as 2-D array. [COP#][SEL] and this is mapped into the guest kernel address space @ VA 0x0. mfc0/mtc0 operations are transformed to load/stores. Signed-off-by: Sanjay Lal <sanjayl@kymasys.com> Cc: kvm@vger.kernel.org Cc: linux-mips@linux-mips.org Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2012-11-22 10:34:16 +08:00
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/vmalloc.h>
#include <linux/fs.h>
#include <linux/bootmem.h>
#include <asm/page.h>
#include <asm/cacheflush.h>
#include <asm/mmu_context.h>
#include <linux/kvm_host.h>
MIPS: KVM: Rename files to remove the prefix "kvm_" and "kvm_mips_" Since all the files are in arch/mips/kvm/, there's no need of the prefixes "kvm_" and "kvm_mips_". Reviewed-by: James Hogan <james.hogan@imgtec.com> Signed-off-by: Deng-Cheng Zhu <dengcheng.zhu@imgtec.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-06-27 03:11:38 +08:00
#include "commpage.h"
KVM/MIPS32: Binary patching of select privileged instructions. Currently, the following instructions are translated: - CACHE (indexed) - CACHE (va based): translated to a SYNCI, overkill on D-CACHE operations, but still much faster than a trap. - mfc0/mtc0: the virtual COP0 registers for the guest are implemented as 2-D array. [COP#][SEL] and this is mapped into the guest kernel address space @ VA 0x0. mfc0/mtc0 operations are transformed to load/stores. Signed-off-by: Sanjay Lal <sanjayl@kymasys.com> Cc: kvm@vger.kernel.org Cc: linux-mips@linux-mips.org Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2012-11-22 10:34:16 +08:00
void kvm_mips_commpage_init(struct kvm_vcpu *vcpu)
{
struct kvm_mips_commpage *page = vcpu->arch.kseg0_commpage;
MIPS: KVM: Reformat code and comments No logic changes inside. Signed-off-by: Deng-Cheng Zhu <dengcheng.zhu@imgtec.com> Reviewed-by: James Hogan <james.hogan@imgtec.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-06-27 03:11:34 +08:00
KVM/MIPS32: Binary patching of select privileged instructions. Currently, the following instructions are translated: - CACHE (indexed) - CACHE (va based): translated to a SYNCI, overkill on D-CACHE operations, but still much faster than a trap. - mfc0/mtc0: the virtual COP0 registers for the guest are implemented as 2-D array. [COP#][SEL] and this is mapped into the guest kernel address space @ VA 0x0. mfc0/mtc0 operations are transformed to load/stores. Signed-off-by: Sanjay Lal <sanjayl@kymasys.com> Cc: kvm@vger.kernel.org Cc: linux-mips@linux-mips.org Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2012-11-22 10:34:16 +08:00
/* Specific init values for fields */
vcpu->arch.cop0 = &page->cop0;
}