KVM: PPC: Make shared struct aka magic page guest endian
The shared (magic) page is a data structure that contains often used
supervisor privileged SPRs accessible via memory to the user to reduce
the number of exits we have to take to read/write them.
When we actually share this structure with the guest we have to maintain
it in guest endianness, because some of the patch tricks only work with
native endian load/store operations.
Since we only share the structure with either host or guest in little
endian on book3s_64 pr mode, we don't have to worry about booke or book3s hv.
For booke, the shared struct stays big endian. For book3s_64 hv we maintain
the struct in host native endian, since it never gets shared with the guest.
For book3s_64 pr we introduce a variable that tells us which endianness the
shared struct is in and route every access to it through helper inline
functions that evaluate this variable.
Signed-off-by: Alexander Graf <agraf@suse.de>
diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c
index d7b0ad2..d424ca0 100644
--- a/arch/powerpc/kvm/book3s_pr.c
+++ b/arch/powerpc/kvm/book3s_pr.c
@@ -246,14 +246,15 @@
static void kvmppc_recalc_shadow_msr(struct kvm_vcpu *vcpu)
{
- ulong smsr = vcpu->arch.shared->msr;
+ ulong guest_msr = kvmppc_get_msr(vcpu);
+ ulong smsr = guest_msr;
/* Guest MSR values */
smsr &= MSR_FE0 | MSR_FE1 | MSR_SF | MSR_SE | MSR_BE | MSR_LE;
/* Process MSR values */
smsr |= MSR_ME | MSR_RI | MSR_IR | MSR_DR | MSR_PR | MSR_EE;
/* External providers the guest reserved */
- smsr |= (vcpu->arch.shared->msr & vcpu->arch.guest_owned_ext);
+ smsr |= (guest_msr & vcpu->arch.guest_owned_ext);
/* 64-bit Process MSR values */
#ifdef CONFIG_PPC_BOOK3S_64
smsr |= MSR_ISF | MSR_HV;
@@ -263,14 +264,14 @@
static void kvmppc_set_msr_pr(struct kvm_vcpu *vcpu, u64 msr)
{
- ulong old_msr = vcpu->arch.shared->msr;
+ ulong old_msr = kvmppc_get_msr(vcpu);
#ifdef EXIT_DEBUG
printk(KERN_INFO "KVM: Set MSR to 0x%llx\n", msr);
#endif
msr &= to_book3s(vcpu)->msr_mask;
- vcpu->arch.shared->msr = msr;
+ kvmppc_set_msr_fast(vcpu, msr);
kvmppc_recalc_shadow_msr(vcpu);
if (msr & MSR_POW) {
@@ -281,11 +282,11 @@
/* Unset POW bit after we woke up */
msr &= ~MSR_POW;
- vcpu->arch.shared->msr = msr;
+ kvmppc_set_msr_fast(vcpu, msr);
}
}
- if ((vcpu->arch.shared->msr & (MSR_PR|MSR_IR|MSR_DR)) !=
+ if ((kvmppc_get_msr(vcpu) & (MSR_PR|MSR_IR|MSR_DR)) !=
(old_msr & (MSR_PR|MSR_IR|MSR_DR))) {
kvmppc_mmu_flush_segments(vcpu);
kvmppc_mmu_map_segment(vcpu, kvmppc_get_pc(vcpu));
@@ -317,7 +318,7 @@
}
/* Preload FPU if it's enabled */
- if (vcpu->arch.shared->msr & MSR_FP)
+ if (kvmppc_get_msr(vcpu) & MSR_FP)
kvmppc_handle_ext(vcpu, BOOK3S_INTERRUPT_FP_UNAVAIL, MSR_FP);
}
@@ -438,7 +439,7 @@
{
ulong mp_pa = vcpu->arch.magic_page_pa;
- if (!(vcpu->arch.shared->msr & MSR_SF))
+ if (!(kvmppc_get_msr(vcpu) & MSR_SF))
mp_pa = (uint32_t)mp_pa;
if (unlikely(mp_pa) &&
@@ -459,8 +460,8 @@
int page_found = 0;
struct kvmppc_pte pte;
bool is_mmio = false;
- bool dr = (vcpu->arch.shared->msr & MSR_DR) ? true : false;
- bool ir = (vcpu->arch.shared->msr & MSR_IR) ? true : false;
+ bool dr = (kvmppc_get_msr(vcpu) & MSR_DR) ? true : false;
+ bool ir = (kvmppc_get_msr(vcpu) & MSR_IR) ? true : false;
u64 vsid;
relocated = data ? dr : ir;
@@ -480,7 +481,7 @@
pte.page_size = MMU_PAGE_64K;
}
- switch (vcpu->arch.shared->msr & (MSR_DR|MSR_IR)) {
+ switch (kvmppc_get_msr(vcpu) & (MSR_DR|MSR_IR)) {
case 0:
pte.vpage |= ((u64)VSID_REAL << (SID_SHIFT - 12));
break;
@@ -488,7 +489,7 @@
case MSR_IR:
vcpu->arch.mmu.esid_to_vsid(vcpu, eaddr >> SID_SHIFT, &vsid);
- if ((vcpu->arch.shared->msr & (MSR_DR|MSR_IR)) == MSR_DR)
+ if ((kvmppc_get_msr(vcpu) & (MSR_DR|MSR_IR)) == MSR_DR)
pte.vpage |= ((u64)VSID_REAL_DR << (SID_SHIFT - 12));
else
pte.vpage |= ((u64)VSID_REAL_IR << (SID_SHIFT - 12));
@@ -511,22 +512,25 @@
if (page_found == -ENOENT) {
/* Page not found in guest PTE entries */
- vcpu->arch.shared->dar = kvmppc_get_fault_dar(vcpu);
- vcpu->arch.shared->dsisr = vcpu->arch.fault_dsisr;
- vcpu->arch.shared->msr |=
- vcpu->arch.shadow_srr1 & 0x00000000f8000000ULL;
+ u64 ssrr1 = vcpu->arch.shadow_srr1;
+ u64 msr = kvmppc_get_msr(vcpu);
+ kvmppc_set_dar(vcpu, kvmppc_get_fault_dar(vcpu));
+ kvmppc_set_dsisr(vcpu, vcpu->arch.fault_dsisr);
+ kvmppc_set_msr_fast(vcpu, msr | (ssrr1 & 0xf8000000ULL));
kvmppc_book3s_queue_irqprio(vcpu, vec);
} else if (page_found == -EPERM) {
/* Storage protection */
- vcpu->arch.shared->dar = kvmppc_get_fault_dar(vcpu);
- vcpu->arch.shared->dsisr = vcpu->arch.fault_dsisr & ~DSISR_NOHPTE;
- vcpu->arch.shared->dsisr |= DSISR_PROTFAULT;
- vcpu->arch.shared->msr |=
- vcpu->arch.shadow_srr1 & 0x00000000f8000000ULL;
+ u32 dsisr = vcpu->arch.fault_dsisr;
+ u64 ssrr1 = vcpu->arch.shadow_srr1;
+ u64 msr = kvmppc_get_msr(vcpu);
+ kvmppc_set_dar(vcpu, kvmppc_get_fault_dar(vcpu));
+ dsisr = (dsisr & ~DSISR_NOHPTE) | DSISR_PROTFAULT;
+ kvmppc_set_dsisr(vcpu, dsisr);
+ kvmppc_set_msr_fast(vcpu, msr | (ssrr1 & 0xf8000000ULL));
kvmppc_book3s_queue_irqprio(vcpu, vec);
} else if (page_found == -EINVAL) {
/* Page not found in guest SLB */
- vcpu->arch.shared->dar = kvmppc_get_fault_dar(vcpu);
+ kvmppc_set_dar(vcpu, kvmppc_get_fault_dar(vcpu));
kvmppc_book3s_queue_irqprio(vcpu, vec + 0x80);
} else if (!is_mmio &&
kvmppc_visible_gfn(vcpu, pte.raddr >> PAGE_SHIFT)) {
@@ -614,11 +618,12 @@
ret = kvmppc_ld(vcpu, &srr0, sizeof(u32), &last_inst, false);
if (ret == -ENOENT) {
- ulong msr = vcpu->arch.shared->msr;
+ ulong msr = kvmppc_get_msr(vcpu);
msr = kvmppc_set_field(msr, 33, 33, 1);
msr = kvmppc_set_field(msr, 34, 36, 0);
- vcpu->arch.shared->msr = kvmppc_set_field(msr, 42, 47, 0);
+ msr = kvmppc_set_field(msr, 42, 47, 0);
+ kvmppc_set_msr_fast(vcpu, msr);
kvmppc_book3s_queue_irqprio(vcpu, BOOK3S_INTERRUPT_INST_STORAGE);
return EMULATE_AGAIN;
}
@@ -651,7 +656,7 @@
if (vcpu->arch.hflags & BOOK3S_HFLAG_PAIRED_SINGLE)
return RESUME_GUEST;
- if (!(vcpu->arch.shared->msr & msr)) {
+ if (!(kvmppc_get_msr(vcpu) & msr)) {
kvmppc_book3s_queue_irqprio(vcpu, exit_nr);
return RESUME_GUEST;
}
@@ -792,7 +797,9 @@
kvmppc_mmu_pte_flush(vcpu, kvmppc_get_pc(vcpu), ~0xFFFUL);
r = RESUME_GUEST;
} else {
- vcpu->arch.shared->msr |= shadow_srr1 & 0x58000000;
+ u64 msr = kvmppc_get_msr(vcpu);
+ msr |= shadow_srr1 & 0x58000000;
+ kvmppc_set_msr_fast(vcpu, msr);
kvmppc_book3s_queue_irqprio(vcpu, exit_nr);
r = RESUME_GUEST;
}
@@ -832,8 +839,8 @@
r = kvmppc_handle_pagefault(run, vcpu, dar, exit_nr);
srcu_read_unlock(&vcpu->kvm->srcu, idx);
} else {
- vcpu->arch.shared->dar = dar;
- vcpu->arch.shared->dsisr = fault_dsisr;
+ kvmppc_set_dar(vcpu, dar);
+ kvmppc_set_dsisr(vcpu, fault_dsisr);
kvmppc_book3s_queue_irqprio(vcpu, exit_nr);
r = RESUME_GUEST;
}
@@ -841,7 +848,7 @@
}
case BOOK3S_INTERRUPT_DATA_SEGMENT:
if (kvmppc_mmu_map_segment(vcpu, kvmppc_get_fault_dar(vcpu)) < 0) {
- vcpu->arch.shared->dar = kvmppc_get_fault_dar(vcpu);
+ kvmppc_set_dar(vcpu, kvmppc_get_fault_dar(vcpu));
kvmppc_book3s_queue_irqprio(vcpu,
BOOK3S_INTERRUPT_DATA_SEGMENT);
}
@@ -879,7 +886,7 @@
program_interrupt:
flags = vcpu->arch.shadow_srr1 & 0x1f0000ull;
- if (vcpu->arch.shared->msr & MSR_PR) {
+ if (kvmppc_get_msr(vcpu) & MSR_PR) {
#ifdef EXIT_DEBUG
printk(KERN_INFO "Userspace triggered 0x700 exception at 0x%lx (0x%x)\n", kvmppc_get_pc(vcpu), kvmppc_get_last_inst(vcpu));
#endif
@@ -921,7 +928,7 @@
case BOOK3S_INTERRUPT_SYSCALL:
if (vcpu->arch.papr_enabled &&
(kvmppc_get_last_sc(vcpu) == 0x44000022) &&
- !(vcpu->arch.shared->msr & MSR_PR)) {
+ !(kvmppc_get_msr(vcpu) & MSR_PR)) {
/* SC 1 papr hypercalls */
ulong cmd = kvmppc_get_gpr(vcpu, 3);
int i;
@@ -953,7 +960,7 @@
gprs[i] = kvmppc_get_gpr(vcpu, i);
vcpu->arch.osi_needed = 1;
r = RESUME_HOST_NV;
- } else if (!(vcpu->arch.shared->msr & MSR_PR) &&
+ } else if (!(kvmppc_get_msr(vcpu) & MSR_PR) &&
(((u32)kvmppc_get_gpr(vcpu, 0)) == KVM_SC_MAGIC_R0)) {
/* KVM PV hypercalls */
kvmppc_set_gpr(vcpu, 3, kvmppc_kvm_pv(vcpu));
@@ -994,10 +1001,16 @@
}
case BOOK3S_INTERRUPT_ALIGNMENT:
if (kvmppc_read_inst(vcpu) == EMULATE_DONE) {
- vcpu->arch.shared->dsisr = kvmppc_alignment_dsisr(vcpu,
- kvmppc_get_last_inst(vcpu));
- vcpu->arch.shared->dar = kvmppc_alignment_dar(vcpu,
- kvmppc_get_last_inst(vcpu));
+ u32 last_inst = kvmppc_get_last_inst(vcpu);
+ u32 dsisr;
+ u64 dar;
+
+ dsisr = kvmppc_alignment_dsisr(vcpu, last_inst);
+ dar = kvmppc_alignment_dar(vcpu, last_inst);
+
+ kvmppc_set_dsisr(vcpu, dsisr);
+ kvmppc_set_dar(vcpu, dar);
+
kvmppc_book3s_queue_irqprio(vcpu, exit_nr);
}
r = RESUME_GUEST;
@@ -1062,7 +1075,7 @@
}
} else {
for (i = 0; i < 16; i++)
- sregs->u.s.ppc32.sr[i] = vcpu->arch.shared->sr[i];
+ sregs->u.s.ppc32.sr[i] = kvmppc_get_sr(vcpu, i);
for (i = 0; i < 8; i++) {
sregs->u.s.ppc32.ibat[i] = vcpu3s->ibat[i].raw;
@@ -1198,8 +1211,14 @@
goto uninit_vcpu;
/* the real shared page fills the last 4k of our page */
vcpu->arch.shared = (void *)(p + PAGE_SIZE - 4096);
-
#ifdef CONFIG_PPC_BOOK3S_64
+ /* Always start the shared struct in native endian mode */
+#ifdef __BIG_ENDIAN__
+ vcpu->arch.shared_big_endian = true;
+#else
+ vcpu->arch.shared_big_endian = false;
+#endif
+
/*
* Default to the same as the host if we're on sufficiently
* recent machine that we have 1TB segments;
@@ -1293,7 +1312,7 @@
#endif
/* Preload FPU if it's enabled */
- if (vcpu->arch.shared->msr & MSR_FP)
+ if (kvmppc_get_msr(vcpu) & MSR_FP)
kvmppc_handle_ext(vcpu, BOOK3S_INTERRUPT_FP_UNAVAIL, MSR_FP);
kvmppc_fix_ee_before_entry();