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linux/arch/arm/kvm/coproc.h

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KVM: ARM: Emulation framework and CP15 emulation Adds a new important function in the main KVM/ARM code called handle_exit() which is called from kvm_arch_vcpu_ioctl_run() on returns from guest execution. This function examines the Hyp-Syndrome-Register (HSR), which contains information telling KVM what caused the exit from the guest. Some of the reasons for an exit are CP15 accesses, which are not allowed from the guest and this commit handles these exits by emulating the intended operation in software and skipping the guest instruction. Minor notes about the coproc register reset: 1) We reserve a value of 0 as an invalid cp15 offset, to catch bugs in our table, at cost of 4 bytes per vcpu. 2) Added comments on the table indicating how we handle each register, for simplicity of understanding. Reviewed-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
2013-01-20 23:28:09 +00:00
/*
* Copyright (C) 2012 - Virtual Open Systems and Columbia University
* Authors: Christoffer Dall <c.dall@virtualopensystems.com>
*
* 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_COPROC_LOCAL_H__
#define __ARM_KVM_COPROC_LOCAL_H__
struct coproc_params {
unsigned long CRn;
unsigned long CRm;
unsigned long Op1;
unsigned long Op2;
unsigned long Rt1;
unsigned long Rt2;
bool is_64bit;
bool is_write;
};
struct coproc_reg {
/* MRC/MCR/MRRC/MCRR instruction which accesses it. */
unsigned long CRn;
unsigned long CRm;
unsigned long Op1;
unsigned long Op2;
bool is_64;
/* Trapped access from guest, if non-NULL. */
bool (*access)(struct kvm_vcpu *,
const struct coproc_params *,
const struct coproc_reg *);
/* Initialization for vcpu. */
void (*reset)(struct kvm_vcpu *, const struct coproc_reg *);
/* Index into vcpu->arch.cp15[], or 0 if we don't need to save it. */
unsigned long reg;
/* Value (usually reset value) */
u64 val;
};
static inline void print_cp_instr(const struct coproc_params *p)
{
/* Look, we even formatted it for you to paste into the table! */
if (p->is_64bit) {
ARM: KVM: fix handling of trapped 64bit coprocessor accesses Commit 240e99cbd00a (ARM: KVM: Fix 64-bit coprocessor handling) changed the way we match the 64bit coprocessor access from user space, but didn't update the trap handler for the same set of registers. The effect is that a trapped 64bit access is never matched, leading to a fault being injected into the guest. This went unnoticed as we didn't really trap any 64bit register so far. Placing the CRm field of the access into the CRn field of the matching structure fixes the problem. Also update the debug feature to emit the expected string in case of failing match. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com>
2014-01-21 18:56:26 +00:00
kvm_pr_unimpl(" { CRm64(%2lu), Op1(%2lu), is64, func_%s },\n",
p->CRn, p->Op1, p->is_write ? "write" : "read");
KVM: ARM: Emulation framework and CP15 emulation Adds a new important function in the main KVM/ARM code called handle_exit() which is called from kvm_arch_vcpu_ioctl_run() on returns from guest execution. This function examines the Hyp-Syndrome-Register (HSR), which contains information telling KVM what caused the exit from the guest. Some of the reasons for an exit are CP15 accesses, which are not allowed from the guest and this commit handles these exits by emulating the intended operation in software and skipping the guest instruction. Minor notes about the coproc register reset: 1) We reserve a value of 0 as an invalid cp15 offset, to catch bugs in our table, at cost of 4 bytes per vcpu. 2) Added comments on the table indicating how we handle each register, for simplicity of understanding. Reviewed-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
2013-01-20 23:28:09 +00:00
} else {
kvm_pr_unimpl(" { CRn(%2lu), CRm(%2lu), Op1(%2lu), Op2(%2lu), is32,"
" func_%s },\n",
p->CRn, p->CRm, p->Op1, p->Op2,
p->is_write ? "write" : "read");
}
}
static inline bool ignore_write(struct kvm_vcpu *vcpu,
const struct coproc_params *p)
{
return true;
}
static inline bool read_zero(struct kvm_vcpu *vcpu,
const struct coproc_params *p)
{
*vcpu_reg(vcpu, p->Rt1) = 0;
return true;
}
static inline bool write_to_read_only(struct kvm_vcpu *vcpu,
const struct coproc_params *params)
{
ARM: KVM: convert GP registers from u32 to unsigned long On 32bit ARM, unsigned long is guaranteed to be a 32bit quantity. On 64bit ARM, it is a 64bit quantity. In order to be able to share code between the two architectures, convert the registers to be unsigned long, so the core code can be oblivious of the change. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-10-03 10:17:02 +00:00
kvm_debug("CP15 write to read-only register at: %08lx\n",
KVM: ARM: Emulation framework and CP15 emulation Adds a new important function in the main KVM/ARM code called handle_exit() which is called from kvm_arch_vcpu_ioctl_run() on returns from guest execution. This function examines the Hyp-Syndrome-Register (HSR), which contains information telling KVM what caused the exit from the guest. Some of the reasons for an exit are CP15 accesses, which are not allowed from the guest and this commit handles these exits by emulating the intended operation in software and skipping the guest instruction. Minor notes about the coproc register reset: 1) We reserve a value of 0 as an invalid cp15 offset, to catch bugs in our table, at cost of 4 bytes per vcpu. 2) Added comments on the table indicating how we handle each register, for simplicity of understanding. Reviewed-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
2013-01-20 23:28:09 +00:00
*vcpu_pc(vcpu));
print_cp_instr(params);
return false;
}
static inline bool read_from_write_only(struct kvm_vcpu *vcpu,
const struct coproc_params *params)
{
ARM: KVM: convert GP registers from u32 to unsigned long On 32bit ARM, unsigned long is guaranteed to be a 32bit quantity. On 64bit ARM, it is a 64bit quantity. In order to be able to share code between the two architectures, convert the registers to be unsigned long, so the core code can be oblivious of the change. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-10-03 10:17:02 +00:00
kvm_debug("CP15 read to write-only register at: %08lx\n",
KVM: ARM: Emulation framework and CP15 emulation Adds a new important function in the main KVM/ARM code called handle_exit() which is called from kvm_arch_vcpu_ioctl_run() on returns from guest execution. This function examines the Hyp-Syndrome-Register (HSR), which contains information telling KVM what caused the exit from the guest. Some of the reasons for an exit are CP15 accesses, which are not allowed from the guest and this commit handles these exits by emulating the intended operation in software and skipping the guest instruction. Minor notes about the coproc register reset: 1) We reserve a value of 0 as an invalid cp15 offset, to catch bugs in our table, at cost of 4 bytes per vcpu. 2) Added comments on the table indicating how we handle each register, for simplicity of understanding. Reviewed-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
2013-01-20 23:28:09 +00:00
*vcpu_pc(vcpu));
print_cp_instr(params);
return false;
}
/* Reset functions */
static inline void reset_unknown(struct kvm_vcpu *vcpu,
const struct coproc_reg *r)
{
BUG_ON(!r->reg);
BUG_ON(r->reg >= ARRAY_SIZE(vcpu->arch.cp15));
vcpu->arch.cp15[r->reg] = 0xdecafbad;
}
static inline void reset_val(struct kvm_vcpu *vcpu, const struct coproc_reg *r)
{
BUG_ON(!r->reg);
BUG_ON(r->reg >= ARRAY_SIZE(vcpu->arch.cp15));
vcpu->arch.cp15[r->reg] = r->val;
}
static inline void reset_unknown64(struct kvm_vcpu *vcpu,
const struct coproc_reg *r)
{
BUG_ON(!r->reg);
BUG_ON(r->reg + 1 >= ARRAY_SIZE(vcpu->arch.cp15));
vcpu->arch.cp15[r->reg] = 0xdecafbad;
vcpu->arch.cp15[r->reg+1] = 0xd0c0ffee;
}
static inline int cmp_reg(const struct coproc_reg *i1,
const struct coproc_reg *i2)
{
BUG_ON(i1 == i2);
if (!i1)
return 1;
else if (!i2)
return -1;
if (i1->CRn != i2->CRn)
return i1->CRn - i2->CRn;
if (i1->CRm != i2->CRm)
return i1->CRm - i2->CRm;
if (i1->Op1 != i2->Op1)
return i1->Op1 - i2->Op1;
ARM: KVM: fix ordering of 64bit coprocessor accesses Commit 240e99cbd00a (ARM: KVM: Fix 64-bit coprocessor handling) added an ordering dependency for the 64bit registers. The order described is: CRn, CRm, Op1, Op2, 64bit-first. Unfortunately, the implementation is: CRn, 64bit-first, CRm... Move the 64bit test to be last in order to match the documentation. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com>
2014-01-21 18:56:26 +00:00
if (i1->Op2 != i2->Op2)
return i1->Op2 - i2->Op2;
return i2->is_64 - i1->is_64;
KVM: ARM: Emulation framework and CP15 emulation Adds a new important function in the main KVM/ARM code called handle_exit() which is called from kvm_arch_vcpu_ioctl_run() on returns from guest execution. This function examines the Hyp-Syndrome-Register (HSR), which contains information telling KVM what caused the exit from the guest. Some of the reasons for an exit are CP15 accesses, which are not allowed from the guest and this commit handles these exits by emulating the intended operation in software and skipping the guest instruction. Minor notes about the coproc register reset: 1) We reserve a value of 0 as an invalid cp15 offset, to catch bugs in our table, at cost of 4 bytes per vcpu. 2) Added comments on the table indicating how we handle each register, for simplicity of understanding. Reviewed-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
2013-01-20 23:28:09 +00:00
}
#define CRn(_x) .CRn = _x
#define CRm(_x) .CRm = _x
ARM: KVM: Fix 64-bit coprocessor handling The PAR was exported as CRn == 7 and CRm == 0, but in fact the primary coprocessor register number was determined by CRm for 64-bit coprocessor registers as the user space API was modeled after the coprocessor access instructions (see the ARM ARM rev. C - B3-1445). However, just changing the CRn to CRm breaks the sorting check when booting the kernel, because the internal kernel logic always treats CRn as the primary register number, and it makes the table sorting impossible to understand for humans. Alternatively we could change the logic to always have CRn == CRm, but that becomes unclear in the number of ways we do look up of a coprocessor register. We could also have a separate 64-bit table but that feels somewhat over-engineered. Instead, keep CRn the primary representation of the primary coproc. register number in-kernel and always export the primary number as CRm as per the existing user space ABI. Note: The TTBR registers just magically worked because they happened to follow the CRn(0) regs and were considered CRn(0) in the in-kernel representation. Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2013-08-06 01:08:41 +00:00
#define CRm64(_x) .CRn = _x, .CRm = 0
KVM: ARM: Emulation framework and CP15 emulation Adds a new important function in the main KVM/ARM code called handle_exit() which is called from kvm_arch_vcpu_ioctl_run() on returns from guest execution. This function examines the Hyp-Syndrome-Register (HSR), which contains information telling KVM what caused the exit from the guest. Some of the reasons for an exit are CP15 accesses, which are not allowed from the guest and this commit handles these exits by emulating the intended operation in software and skipping the guest instruction. Minor notes about the coproc register reset: 1) We reserve a value of 0 as an invalid cp15 offset, to catch bugs in our table, at cost of 4 bytes per vcpu. 2) Added comments on the table indicating how we handle each register, for simplicity of understanding. Reviewed-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
2013-01-20 23:28:09 +00:00
#define Op1(_x) .Op1 = _x
#define Op2(_x) .Op2 = _x
#define is64 .is_64 = true
#define is32 .is_64 = false
arm/arm64: KVM: Use set/way op trapping to track the state of the caches Trying to emulate the behaviour of set/way cache ops is fairly pointless, as there are too many ways we can end-up missing stuff. Also, there is some system caches out there that simply ignore set/way operations. So instead of trying to implement them, let's convert it to VA ops, and use them as a way to re-enable the trapping of VM ops. That way, we can detect the point when the MMU/caches are turned off, and do a full VM flush (which is what the guest was trying to do anyway). This allows a 32bit zImage to boot on the APM thingy, and will probably help bootloaders in general. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-12-19 16:05:31 +00:00
bool access_vm_reg(struct kvm_vcpu *vcpu,
const struct coproc_params *p,
const struct coproc_reg *r);
ARM: KVM: trap VM system registers until MMU and caches are ON In order to be able to detect the point where the guest enables its MMU and caches, trap all the VM related system registers. Once we see the guest enabling both the MMU and the caches, we can go back to a saner mode of operation, which is to leave these registers in complete control of the guest. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-01-14 18:00:55 +00:00
KVM: ARM: Emulation framework and CP15 emulation Adds a new important function in the main KVM/ARM code called handle_exit() which is called from kvm_arch_vcpu_ioctl_run() on returns from guest execution. This function examines the Hyp-Syndrome-Register (HSR), which contains information telling KVM what caused the exit from the guest. Some of the reasons for an exit are CP15 accesses, which are not allowed from the guest and this commit handles these exits by emulating the intended operation in software and skipping the guest instruction. Minor notes about the coproc register reset: 1) We reserve a value of 0 as an invalid cp15 offset, to catch bugs in our table, at cost of 4 bytes per vcpu. 2) Added comments on the table indicating how we handle each register, for simplicity of understanding. Reviewed-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
2013-01-20 23:28:09 +00:00
#endif /* __ARM_KVM_COPROC_LOCAL_H__ */
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