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KVM: MIPS: Remove duplicated ASIDs from vcpu

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The kvm_vcpu_arch structure contains both mm_structs for allocating MMU
contexts (primarily the ASID) but it also copies the resulting ASIDs
into guest_{user,kernel}_asid[] arrays which are referenced from uasm
generated code.

This duplication doesn't seem to serve any purpose, and it gets in the
way of generalising the ASID handling across guest kernel/user modes, so
lets just extract the ASID straight out of the mm_struct on demand, and
in fact there are convenient cpu_context() and cpu_asid() macros for
doing so.

To reduce the verbosity of this code we do also add kern_mm and user_mm
local variables where the kernel and user mm_structs are used.

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
This commit is contained in:
James Hogan
2016-10-11 23:14:39 +01:00
parent 1581ff3dbf
commit c550d53934
7 changed files with 44 additions and 48 deletions
Download Patch File Download Diff File Expand all files Collapse all files

8
arch/mips/kvm/mips.c
View File

@@ -413,6 +413,7 @@ int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
/* Must be called with preemption disabled, just before entering guest */
static void kvm_mips_check_asids(struct kvm_vcpu *vcpu)
{
struct mm_struct *user_mm = &vcpu->arch.guest_user_mm;
struct mips_coproc *cop0 = vcpu->arch.cop0;
int i, cpu = smp_processor_id();
unsigned int gasid;
@@ -426,13 +427,10 @@ static void kvm_mips_check_asids(struct kvm_vcpu *vcpu)
if (!KVM_GUEST_KERNEL_MODE(vcpu)) {
gasid = kvm_read_c0_guest_entryhi(cop0) & KVM_ENTRYHI_ASID;
if (gasid != vcpu->arch.last_user_gasid) {
kvm_get_new_mmu_context(&vcpu->arch.guest_user_mm, cpu,
vcpu);
vcpu->arch.guest_user_asid[cpu] =
vcpu->arch.guest_user_mm.context.asid[cpu];
kvm_get_new_mmu_context(user_mm, cpu, vcpu);
for_each_possible_cpu(i)
if (i != cpu)
vcpu->arch.guest_user_asid[cpu] = 0;
cpu_context(i, user_mm) = 0;
vcpu->arch.last_user_gasid = gasid;
}
}