@@ -259,6 +259,9 @@ struct kvm_arch {
struct kvmppc_vcore *vcores[KVM_MAX_VCORES];
int hpt_cma_alloc;
#endif /* CONFIG_KVM_BOOK3S_64_HV */
+#ifdef CONFIG_KVM_BOOK3S_64_PR
+ struct mutex hpt_mutex;
+#endif
#ifdef CONFIG_PPC_BOOK3S_64
struct list_head spapr_tce_tables;
struct list_head rtas_tokens;
@@ -257,6 +257,8 @@ static int kvmppc_mmu_book3s_64_xlate(struct kvm_vcpu *vcpu, gva_t eaddr,
pgsize = slbe->large ? MMU_PAGE_16M : MMU_PAGE_4K;
+ mutex_lock(&vcpu->kvm->arch.hpt_mutex);
+
do_second:
ptegp = kvmppc_mmu_book3s_64_get_pteg(vcpu_book3s, slbe, eaddr, second);
if (kvm_is_error_hva(ptegp))
@@ -332,30 +334,37 @@ do_second:
/* Update PTE R and C bits, so the guest's swapper knows we used the
* page */
- if (gpte->may_read) {
- /* Set the accessed flag */
+ if (gpte->may_read && !(r & HPTE_R_R)) {
+ /*
+ * Set the accessed flag.
+ * We have to write this back with a single byte write
+ * because another vcpu may be accessing this on
+ * non-PAPR platforms such as mac99, and this is
+ * what real hardware does.
+ */
+ char __user *addr = (char __user *) &pteg[i+1];
r |= HPTE_R_R;
+ put_user(r >> 8, addr + 6);
}
- if (data && gpte->may_write) {
+ if (data && gpte->may_write && !(r & HPTE_R_C)) {
/* Set the dirty flag -- XXX even if not writing */
+ /* Use a single byte write */
+ char __user *addr = (char __user *) &pteg[i+1];
r |= HPTE_R_C;
+ put_user(r, addr + 7);
}
- /* Write back into the PTEG */
- if (pteg[i+1] != r) {
- pteg[i+1] = r;
- copy_to_user((void __user *)ptegp, pteg, sizeof(pteg));
- }
+ mutex_unlock(&vcpu->kvm->arch.hpt_mutex);
if (!gpte->may_read)
return -EPERM;
return 0;
no_page_found:
+ mutex_unlock(&vcpu->kvm->arch.hpt_mutex);
return -ENOENT;
no_seg_found:
-
dprintk("KVM MMU: Trigger segment fault\n");
return -EINVAL;
}
@@ -520,6 +529,8 @@ static void kvmppc_mmu_book3s_64_tlbie(struct kvm_vcpu *vcpu, ulong va,
bool large)
{
u64 mask = 0xFFFFFFFFFULL;
+ long i;
+ struct kvm_vcpu *v;
dprintk("KVM MMU: tlbie(0x%lx)\n", va);
@@ -542,7 +553,9 @@ static void kvmppc_mmu_book3s_64_tlbie(struct kvm_vcpu *vcpu, ulong va,
if (large)
mask = 0xFFFFFF000ULL;
}
- kvmppc_mmu_pte_vflush(vcpu, va >> 12, mask);
+ /* flush this VA on all vcpus */
+ kvm_for_each_vcpu(i, v, vcpu->kvm)
+ kvmppc_mmu_pte_vflush(v, va >> 12, mask);
}
#ifdef CONFIG_PPC_64K_PAGES
@@ -1326,6 +1326,7 @@ int kvmppc_core_init_vm(struct kvm *kvm)
INIT_LIST_HEAD(&kvm->arch.spapr_tce_tables);
INIT_LIST_HEAD(&kvm->arch.rtas_tokens);
#endif
+ mutex_init(&kvm->arch.hpt_mutex);
if (firmware_has_feature(FW_FEATURE_SET_MODE)) {
spin_lock(&kvm_global_user_count_lock);
@@ -48,6 +48,7 @@ static int kvmppc_h_pr_enter(struct kvm_vcpu *vcpu)
pte_index &= ~7UL;
pteg_addr = get_pteg_addr(vcpu, pte_index);
+ mutex_lock(&vcpu->kvm->arch.hpt_mutex);
copy_from_user(pteg, (void __user *)pteg_addr, sizeof(pteg));
hpte = pteg;
@@ -74,6 +75,7 @@ static int kvmppc_h_pr_enter(struct kvm_vcpu *vcpu)
ret = H_SUCCESS;
done:
+ mutex_unlock(&vcpu->kvm->arch.hpt_mutex);
kvmppc_set_gpr(vcpu, 3, ret);
return EMULATE_DONE;
@@ -86,26 +88,31 @@ static int kvmppc_h_pr_remove(struct kvm_vcpu *vcpu)
unsigned long avpn = kvmppc_get_gpr(vcpu, 6);
unsigned long v = 0, pteg, rb;
unsigned long pte[2];
+ long int ret;
pteg = get_pteg_addr(vcpu, pte_index);
+ mutex_lock(&vcpu->kvm->arch.hpt_mutex);
copy_from_user(pte, (void __user *)pteg, sizeof(pte));
+ ret = H_NOT_FOUND;
if ((pte[0] & HPTE_V_VALID) == 0 ||
((flags & H_AVPN) && (pte[0] & ~0x7fUL) != avpn) ||
- ((flags & H_ANDCOND) && (pte[0] & avpn) != 0)) {
- kvmppc_set_gpr(vcpu, 3, H_NOT_FOUND);
- return EMULATE_DONE;
- }
+ ((flags & H_ANDCOND) && (pte[0] & avpn) != 0))
+ goto done;
copy_to_user((void __user *)pteg, &v, sizeof(v));
rb = compute_tlbie_rb(pte[0], pte[1], pte_index);
vcpu->arch.mmu.tlbie(vcpu, rb, rb & 1 ? true : false);
- kvmppc_set_gpr(vcpu, 3, H_SUCCESS);
+ ret = H_SUCCESS;
kvmppc_set_gpr(vcpu, 4, pte[0]);
kvmppc_set_gpr(vcpu, 5, pte[1]);
+ done:
+ mutex_unlock(&vcpu->kvm->arch.hpt_mutex);
+ kvmppc_set_gpr(vcpu, 3, ret);
+
return EMULATE_DONE;
}
@@ -133,6 +140,7 @@ static int kvmppc_h_pr_bulk_remove(struct kvm_vcpu *vcpu)
int paramnr = 4;
int ret = H_SUCCESS;
+ mutex_lock(&vcpu->kvm->arch.hpt_mutex);
for (i = 0; i < H_BULK_REMOVE_MAX_BATCH; i++) {
unsigned long tsh = kvmppc_get_gpr(vcpu, paramnr+(2*i));
unsigned long tsl = kvmppc_get_gpr(vcpu, paramnr+(2*i)+1);
@@ -181,6 +189,7 @@ static int kvmppc_h_pr_bulk_remove(struct kvm_vcpu *vcpu)
}
kvmppc_set_gpr(vcpu, paramnr+(2*i), tsh);
}
+ mutex_unlock(&vcpu->kvm->arch.hpt_mutex);
kvmppc_set_gpr(vcpu, 3, ret);
return EMULATE_DONE;
@@ -193,15 +202,16 @@ static int kvmppc_h_pr_protect(struct kvm_vcpu *vcpu)
unsigned long avpn = kvmppc_get_gpr(vcpu, 6);
unsigned long rb, pteg, r, v;
unsigned long pte[2];
+ long int ret;
pteg = get_pteg_addr(vcpu, pte_index);
+ mutex_lock(&vcpu->kvm->arch.hpt_mutex);
copy_from_user(pte, (void __user *)pteg, sizeof(pte));
+ ret = H_NOT_FOUND;
if ((pte[0] & HPTE_V_VALID) == 0 ||
- ((flags & H_AVPN) && (pte[0] & ~0x7fUL) != avpn)) {
- kvmppc_set_gpr(vcpu, 3, H_NOT_FOUND);
- return EMULATE_DONE;
- }
+ ((flags & H_AVPN) && (pte[0] & ~0x7fUL) != avpn))
+ goto done;
v = pte[0];
r = pte[1];
@@ -216,8 +226,11 @@ static int kvmppc_h_pr_protect(struct kvm_vcpu *vcpu)
rb = compute_tlbie_rb(v, r, pte_index);
vcpu->arch.mmu.tlbie(vcpu, rb, rb & 1 ? true : false);
copy_to_user((void __user *)pteg, pte, sizeof(pte));
+ ret = H_SUCCESS;
- kvmppc_set_gpr(vcpu, 3, H_SUCCESS);
+ done:
+ mutex_unlock(&vcpu->kvm->arch.hpt_mutex);
+ kvmppc_set_gpr(vcpu, 3, ret);
return EMULATE_DONE;
}
This adds a per-VM mutex to provide mutual exclusion between vcpus for accesses to and updates of the guest hashed page table (HPT). This also makes the code use single-byte writes to the HPT entry when updating of the reference (R) and change (C) bits. The reason for doing this, rather than writing back the whole HPTE, is that on non-PAPR virtual machines, the guest OS might be writing to the HPTE concurrently, and writing back the whole HPTE might conflict with that. Also, real hardware does single-byte writes to update R and C. The new mutex is taken in kvmppc_mmu_book3s_64_xlate() when reading the HPT and updating R and/or C, and in the PAPR HPT update hcalls (H_ENTER, H_REMOVE, etc.). The other change here is to make emulated TLB invalidations (tlbie) effective across all vcpus. To do this we call kvmppc_mmu_pte_vflush for all vcpus in kvmppc_ppc_book3s_64_tlbie(). With this, PR KVM can successfully run SMP guests. Signed-off-by: Paul Mackerras <paulus@samba.org> --- arch/powerpc/include/asm/kvm_host.h | 3 +++ arch/powerpc/kvm/book3s_64_mmu.c | 33 +++++++++++++++++++++++---------- arch/powerpc/kvm/book3s_pr.c | 1 + arch/powerpc/kvm/book3s_pr_papr.c | 33 +++++++++++++++++++++++---------- 4 files changed, 50 insertions(+), 20 deletions(-)