redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

KVM: nVMX: rearrange get_vmx_mem_address 

Our common function for vmptr checks (in 2/4) needs to fetch
the memory address

Signed-off-by: Bandan Das <bsd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
hifive-unleashed-5.1
Bandan Das 2014-05-06 02:19:15 -04:00 committed by Paolo Bonzini
parent 2ce316f0b9
commit 19677e32fe
1 changed files with 53 additions and 53 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

106
arch/x86/kvm/vmx.c
View File

@ -5791,6 +5791,59 @@ static enum hrtimer_restart vmx_preemption_timer_fn(struct hrtimer *timer)
return HRTIMER_NORESTART;
}
/*
* Decode the memory-address operand of a vmx instruction, as recorded on an
* exit caused by such an instruction (run by a guest hypervisor).
* On success, returns 0. When the operand is invalid, returns 1 and throws
* #UD or #GP.
*/
static int get_vmx_mem_address(struct kvm_vcpu *vcpu,
unsigned long exit_qualification,
u32 vmx_instruction_info, gva_t *ret)
{
/*
* According to Vol. 3B, "Information for VM Exits Due to Instruction
* Execution", on an exit, vmx_instruction_info holds most of the
* addressing components of the operand. Only the displacement part
* is put in exit_qualification (see 3B, "Basic VM-Exit Information").
* For how an actual address is calculated from all these components,
* refer to Vol. 1, "Operand Addressing".
*/
int scaling = vmx_instruction_info & 3;
int addr_size = (vmx_instruction_info >> 7) & 7;
bool is_reg = vmx_instruction_info & (1u << 10);
int seg_reg = (vmx_instruction_info >> 15) & 7;
int index_reg = (vmx_instruction_info >> 18) & 0xf;
bool index_is_valid = !(vmx_instruction_info & (1u << 22));
int base_reg = (vmx_instruction_info >> 23) & 0xf;
bool base_is_valid = !(vmx_instruction_info & (1u << 27));
if (is_reg) {
kvm_queue_exception(vcpu, UD_VECTOR);
return 1;
}
/* Addr = segment_base + offset */
/* offset = base + [index * scale] + displacement */
*ret = vmx_get_segment_base(vcpu, seg_reg);
if (base_is_valid)
*ret += kvm_register_read(vcpu, base_reg);
if (index_is_valid)
*ret += kvm_register_read(vcpu, index_reg)<<scaling;
*ret += exit_qualification; /* holds the displacement */
if (addr_size == 1) /* 32 bit */
*ret &= 0xffffffff;
/*
* TODO: throw #GP (and return 1) in various cases that the VM*
* instructions require it - e.g., offset beyond segment limit,
* unusable or unreadable/unwritable segment, non-canonical 64-bit
* address, and so on. Currently these are not checked.
*/
return 0;
}
/*
* Emulate the VMXON instruction.
* Currently, we just remember that VMX is active, and do not save or even
@ -5951,59 +6004,6 @@ static int handle_vmoff(struct kvm_vcpu *vcpu)
return 1;
}
/*
* Decode the memory-address operand of a vmx instruction, as recorded on an
* exit caused by such an instruction (run by a guest hypervisor).
* On success, returns 0. When the operand is invalid, returns 1 and throws
* #UD or #GP.
*/
static int get_vmx_mem_address(struct kvm_vcpu *vcpu,
unsigned long exit_qualification,
u32 vmx_instruction_info, gva_t *ret)
{
/*
* According to Vol. 3B, "Information for VM Exits Due to Instruction
* Execution", on an exit, vmx_instruction_info holds most of the
* addressing components of the operand. Only the displacement part
* is put in exit_qualification (see 3B, "Basic VM-Exit Information").
* For how an actual address is calculated from all these components,
* refer to Vol. 1, "Operand Addressing".
*/
int scaling = vmx_instruction_info & 3;
int addr_size = (vmx_instruction_info >> 7) & 7;
bool is_reg = vmx_instruction_info & (1u << 10);
int seg_reg = (vmx_instruction_info >> 15) & 7;
int index_reg = (vmx_instruction_info >> 18) & 0xf;
bool index_is_valid = !(vmx_instruction_info & (1u << 22));
int base_reg = (vmx_instruction_info >> 23) & 0xf;
bool base_is_valid = !(vmx_instruction_info & (1u << 27));
if (is_reg) {
kvm_queue_exception(vcpu, UD_VECTOR);
return 1;
}
/* Addr = segment_base + offset */
/* offset = base + [index * scale] + displacement */
*ret = vmx_get_segment_base(vcpu, seg_reg);
if (base_is_valid)
*ret += kvm_register_read(vcpu, base_reg);
if (index_is_valid)
*ret += kvm_register_read(vcpu, index_reg)<<scaling;
*ret += exit_qualification; /* holds the displacement */
if (addr_size == 1) /* 32 bit */
*ret &= 0xffffffff;
/*
* TODO: throw #GP (and return 1) in various cases that the VM*
* instructions require it - e.g., offset beyond segment limit,
* unusable or unreadable/unwritable segment, non-canonical 64-bit
* address, and so on. Currently these are not checked.
*/
return 0;
}
/* Emulate the VMCLEAR instruction */
static int handle_vmclear(struct kvm_vcpu *vcpu)
{