KVM: MIPS: Remove duplicated ASIDs from vcpu
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
diff --git a/arch/mips/include/asm/kvm_host.h b/arch/mips/include/asm/kvm_host.h
index 1c70b52..923f81d 100644
--- a/arch/mips/include/asm/kvm_host.h
+++ b/arch/mips/include/asm/kvm_host.h
@@ -321,9 +321,7 @@
/* S/W Based TLB for guest */
struct kvm_mips_tlb guest_tlb[KVM_MIPS_GUEST_TLB_SIZE];
- /* Cached guest kernel/user ASIDs */
- u32 guest_user_asid[NR_CPUS];
- u32 guest_kernel_asid[NR_CPUS];
+ /* Guest kernel/user [partial] mm */
struct mm_struct guest_kernel_mm, guest_user_mm;
/* Guest ASID of last user mode execution */
diff --git a/arch/mips/kvm/emulate.c b/arch/mips/kvm/emulate.c
index aa09374..060acc5 100644
--- a/arch/mips/kvm/emulate.c
+++ b/arch/mips/kvm/emulate.c
@@ -856,6 +856,8 @@
static void kvm_mips_invalidate_guest_tlb(struct kvm_vcpu *vcpu,
struct kvm_mips_tlb *tlb)
{
+ struct mm_struct *kern_mm = &vcpu->arch.guest_kernel_mm;
+ struct mm_struct *user_mm = &vcpu->arch.guest_user_mm;
int cpu, i;
bool user;
@@ -879,8 +881,8 @@
if (i == cpu)
continue;
if (user)
- vcpu->arch.guest_user_asid[i] = 0;
- vcpu->arch.guest_kernel_asid[i] = 0;
+ cpu_context(i, user_mm) = 0;
+ cpu_context(i, kern_mm) = 0;
}
preempt_enable();
@@ -1056,6 +1058,7 @@
struct kvm_vcpu *vcpu)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
+ struct mm_struct *kern_mm = &vcpu->arch.guest_kernel_mm;
enum emulation_result er = EMULATE_DONE;
u32 rt, rd, sel;
unsigned long curr_pc;
@@ -1178,13 +1181,11 @@
*/
preempt_disable();
cpu = smp_processor_id();
- kvm_get_new_mmu_context(&vcpu->arch.guest_kernel_mm,
+ kvm_get_new_mmu_context(kern_mm,
cpu, vcpu);
- vcpu->arch.guest_kernel_asid[cpu] =
- vcpu->arch.guest_kernel_mm.context.asid[cpu];
for_each_possible_cpu(i)
if (i != cpu)
- vcpu->arch.guest_kernel_asid[i] = 0;
+ cpu_context(i, kern_mm) = 0;
preempt_enable();
}
kvm_write_c0_guest_entryhi(cop0,
diff --git a/arch/mips/kvm/entry.c b/arch/mips/kvm/entry.c
index e92fb19..f818887 100644
--- a/arch/mips/kvm/entry.c
+++ b/arch/mips/kvm/entry.c
@@ -12,6 +12,7 @@
*/
#include <linux/kvm_host.h>
+#include <linux/log2.h>
#include <asm/msa.h>
#include <asm/setup.h>
#include <asm/uasm.h>
@@ -286,23 +287,26 @@
uasm_i_andi(&p, T0, T0, KSU_USER | ST0_ERL | ST0_EXL);
uasm_i_xori(&p, T0, T0, KSU_USER);
uasm_il_bnez(&p, &r, T0, label_kernel_asid);
- UASM_i_ADDIU(&p, T1, K1,
- offsetof(struct kvm_vcpu_arch, guest_kernel_asid));
+ UASM_i_ADDIU(&p, T1, K1, offsetof(struct kvm_vcpu_arch,
+ guest_kernel_mm.context.asid));
/* else user */
- UASM_i_ADDIU(&p, T1, K1,
- offsetof(struct kvm_vcpu_arch, guest_user_asid));
+ UASM_i_ADDIU(&p, T1, K1, offsetof(struct kvm_vcpu_arch,
+ guest_user_mm.context.asid));
uasm_l_kernel_asid(&l, p);
/* t1: contains the base of the ASID array, need to get the cpu id */
/* smp_processor_id */
uasm_i_lw(&p, T2, offsetof(struct thread_info, cpu), GP);
- /* x4 */
- uasm_i_sll(&p, T2, T2, 2);
+ /* index the ASID array */
+ uasm_i_sll(&p, T2, T2, ilog2(sizeof(long)));
UASM_i_ADDU(&p, T3, T1, T2);
- uasm_i_lw(&p, K0, 0, T3);
+ UASM_i_LW(&p, K0, 0, T3);
#ifdef CONFIG_MIPS_ASID_BITS_VARIABLE
- /* x sizeof(struct cpuinfo_mips)/4 */
- uasm_i_addiu(&p, T3, ZERO, sizeof(struct cpuinfo_mips)/4);
+ /*
+ * reuse ASID array offset
+ * cpuinfo_mips is a multiple of sizeof(long)
+ */
+ uasm_i_addiu(&p, T3, ZERO, sizeof(struct cpuinfo_mips)/sizeof(long));
uasm_i_mul(&p, T2, T2, T3);
UASM_i_LA_mostly(&p, AT, (long)&cpu_data[0].asid_mask);
diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c
index f9e305f..85bc54f 100644
--- a/arch/mips/kvm/mips.c
+++ b/arch/mips/kvm/mips.c
@@ -413,6 +413,7 @@
/* 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 @@
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;
}
}
diff --git a/arch/mips/kvm/mmu.c b/arch/mips/kvm/mmu.c
index df013538..27d6d0d 100644
--- a/arch/mips/kvm/mmu.c
+++ b/arch/mips/kvm/mmu.c
@@ -15,18 +15,18 @@
static u32 kvm_mips_get_kernel_asid(struct kvm_vcpu *vcpu)
{
+ struct mm_struct *kern_mm = &vcpu->arch.guest_kernel_mm;
int cpu = smp_processor_id();
- return vcpu->arch.guest_kernel_asid[cpu] &
- cpu_asid_mask(&cpu_data[cpu]);
+ return cpu_asid(cpu, kern_mm);
}
static u32 kvm_mips_get_user_asid(struct kvm_vcpu *vcpu)
{
+ struct mm_struct *user_mm = &vcpu->arch.guest_user_mm;
int cpu = smp_processor_id();
- return vcpu->arch.guest_user_asid[cpu] &
- cpu_asid_mask(&cpu_data[cpu]);
+ return cpu_asid(cpu, user_mm);
}
static int kvm_mips_map_page(struct kvm *kvm, gfn_t gfn)
diff --git a/arch/mips/kvm/tlb.c b/arch/mips/kvm/tlb.c
index 254377d..ba49013 100644
--- a/arch/mips/kvm/tlb.c
+++ b/arch/mips/kvm/tlb.c
@@ -38,18 +38,18 @@
static u32 kvm_mips_get_kernel_asid(struct kvm_vcpu *vcpu)
{
+ struct mm_struct *kern_mm = &vcpu->arch.guest_kernel_mm;
int cpu = smp_processor_id();
- return vcpu->arch.guest_kernel_asid[cpu] &
- cpu_asid_mask(&cpu_data[cpu]);
+ return cpu_asid(cpu, kern_mm);
}
static u32 kvm_mips_get_user_asid(struct kvm_vcpu *vcpu)
{
+ struct mm_struct *user_mm = &vcpu->arch.guest_user_mm;
int cpu = smp_processor_id();
- return vcpu->arch.guest_user_asid[cpu] &
- cpu_asid_mask(&cpu_data[cpu]);
+ return cpu_asid(cpu, user_mm);
}
inline u32 kvm_mips_get_commpage_asid(struct kvm_vcpu *vcpu)
diff --git a/arch/mips/kvm/trap_emul.c b/arch/mips/kvm/trap_emul.c
index 494a902..c7854d3 100644
--- a/arch/mips/kvm/trap_emul.c
+++ b/arch/mips/kvm/trap_emul.c
@@ -635,32 +635,29 @@
static int kvm_trap_emul_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
{
- unsigned long asid_mask = cpu_asid_mask(&cpu_data[cpu]);
+ struct mm_struct *kern_mm = &vcpu->arch.guest_kernel_mm;
+ struct mm_struct *user_mm = &vcpu->arch.guest_user_mm;
/* Allocate new kernel and user ASIDs if needed */
- if ((vcpu->arch.guest_kernel_asid[cpu] ^ asid_cache(cpu)) &
+ if ((cpu_context(cpu, kern_mm) ^ asid_cache(cpu)) &
asid_version_mask(cpu)) {
- kvm_get_new_mmu_context(&vcpu->arch.guest_kernel_mm, cpu, vcpu);
- vcpu->arch.guest_kernel_asid[cpu] =
- vcpu->arch.guest_kernel_mm.context.asid[cpu];
+ kvm_get_new_mmu_context(kern_mm, cpu, vcpu);
kvm_debug("[%d]: cpu_context: %#lx\n", cpu,
cpu_context(cpu, current->mm));
- kvm_debug("[%d]: Allocated new ASID for Guest Kernel: %#x\n",
- cpu, vcpu->arch.guest_kernel_asid[cpu]);
+ kvm_debug("[%d]: Allocated new ASID for Guest Kernel: %#lx\n",
+ cpu, cpu_context(cpu, kern_mm));
}
- if ((vcpu->arch.guest_user_asid[cpu] ^ asid_cache(cpu)) &
+ if ((cpu_context(cpu, user_mm) ^ asid_cache(cpu)) &
asid_version_mask(cpu)) {
- 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);
kvm_debug("[%d]: cpu_context: %#lx\n", cpu,
cpu_context(cpu, current->mm));
- kvm_debug("[%d]: Allocated new ASID for Guest User: %#x\n", cpu,
- vcpu->arch.guest_user_asid[cpu]);
+ kvm_debug("[%d]: Allocated new ASID for Guest User: %#lx\n",
+ cpu, cpu_context(cpu, user_mm));
}
/*
@@ -670,11 +667,9 @@
*/
if (current->flags & PF_VCPU) {
if (KVM_GUEST_KERNEL_MODE(vcpu))
- write_c0_entryhi(vcpu->arch.guest_kernel_asid[cpu] &
- asid_mask);
+ write_c0_entryhi(cpu_asid(cpu, kern_mm));
else
- write_c0_entryhi(vcpu->arch.guest_user_asid[cpu] &
- asid_mask);
+ write_c0_entryhi(cpu_asid(cpu, user_mm));
ehb();
}