[PATCH v3 31/41] KVM: PPC: Book3S HV P9: Add helpers for OS SPR handling
Nicholas Piggin
npiggin at gmail.com
Sat Mar 6 02:06:28 AEDT 2021
This is a first step to wrapping supervisor and user SPR saving and
loading up into helpers, which will then be called independently in
bare metal and nested HV cases in order to optimise SPR access.
Signed-off-by: Nicholas Piggin <npiggin at gmail.com>
---
arch/powerpc/kvm/book3s_hv.c | 141 ++++++++++++++++++++++-------------
1 file changed, 89 insertions(+), 52 deletions(-)
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 3e77b0ba1bf6..36679b1391a6 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -3457,6 +3457,89 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc)
trace_kvmppc_run_core(vc, 1);
}
+static void load_spr_state(struct kvm_vcpu *vcpu)
+{
+ mtspr(SPRN_DSCR, vcpu->arch.dscr);
+ mtspr(SPRN_IAMR, vcpu->arch.iamr);
+ mtspr(SPRN_PSPB, vcpu->arch.pspb);
+ mtspr(SPRN_FSCR, vcpu->arch.fscr);
+ mtspr(SPRN_TAR, vcpu->arch.tar);
+ mtspr(SPRN_EBBHR, vcpu->arch.ebbhr);
+ mtspr(SPRN_EBBRR, vcpu->arch.ebbrr);
+ mtspr(SPRN_BESCR, vcpu->arch.bescr);
+ mtspr(SPRN_WORT, vcpu->arch.wort);
+ mtspr(SPRN_TIDR, vcpu->arch.tid);
+ mtspr(SPRN_AMR, vcpu->arch.amr);
+ mtspr(SPRN_UAMOR, vcpu->arch.uamor);
+
+ /*
+ * DAR, DSISR, and for nested HV, SPRGs must be set with MSR[RI]
+ * clear (or hstate set appropriately to catch those registers
+ * being clobbered if we take a MCE or SRESET), so those are done
+ * later.
+ */
+
+ if (!(vcpu->arch.ctrl & 1))
+ mtspr(SPRN_CTRLT, mfspr(SPRN_CTRLF) & ~1);
+}
+
+static void store_spr_state(struct kvm_vcpu *vcpu)
+{
+ vcpu->arch.ctrl = mfspr(SPRN_CTRLF);
+
+ vcpu->arch.iamr = mfspr(SPRN_IAMR);
+ vcpu->arch.pspb = mfspr(SPRN_PSPB);
+ vcpu->arch.fscr = mfspr(SPRN_FSCR);
+ vcpu->arch.tar = mfspr(SPRN_TAR);
+ vcpu->arch.ebbhr = mfspr(SPRN_EBBHR);
+ vcpu->arch.ebbrr = mfspr(SPRN_EBBRR);
+ vcpu->arch.bescr = mfspr(SPRN_BESCR);
+ vcpu->arch.wort = mfspr(SPRN_WORT);
+ vcpu->arch.tid = mfspr(SPRN_TIDR);
+ vcpu->arch.amr = mfspr(SPRN_AMR);
+ vcpu->arch.uamor = mfspr(SPRN_UAMOR);
+ vcpu->arch.dscr = mfspr(SPRN_DSCR);
+}
+
+/*
+ * Privileged (non-hypervisor) host registers to save.
+ */
+struct p9_host_os_sprs {
+ unsigned long dscr;
+ unsigned long tidr;
+ unsigned long iamr;
+ unsigned long amr;
+ unsigned long fscr;
+};
+
+static void save_p9_host_os_sprs(struct p9_host_os_sprs *host_os_sprs)
+{
+ host_os_sprs->dscr = mfspr(SPRN_DSCR);
+ host_os_sprs->tidr = mfspr(SPRN_TIDR);
+ host_os_sprs->iamr = mfspr(SPRN_IAMR);
+ host_os_sprs->amr = mfspr(SPRN_AMR);
+ host_os_sprs->fscr = mfspr(SPRN_FSCR);
+}
+
+/* vcpu guest regs must already be saved */
+static void restore_p9_host_os_sprs(struct kvm_vcpu *vcpu,
+ struct p9_host_os_sprs *host_os_sprs)
+{
+ mtspr(SPRN_PSPB, 0);
+ mtspr(SPRN_WORT, 0);
+ mtspr(SPRN_UAMOR, 0);
+
+ mtspr(SPRN_DSCR, host_os_sprs->dscr);
+ mtspr(SPRN_TIDR, host_os_sprs->tidr);
+ mtspr(SPRN_IAMR, host_os_sprs->iamr);
+
+ if (host_os_sprs->amr != vcpu->arch.amr)
+ mtspr(SPRN_AMR, host_os_sprs->amr);
+
+ if (host_os_sprs->fscr != vcpu->arch.fscr)
+ mtspr(SPRN_FSCR, host_os_sprs->fscr);
+}
+
/*
* Virtual-mode guest entry for POWER9 and later when the host and
* guest are both using the radix MMU. The LPIDR has already been set.
@@ -3465,11 +3548,7 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
unsigned long lpcr)
{
struct kvmppc_vcore *vc = vcpu->arch.vcore;
- unsigned long host_dscr = mfspr(SPRN_DSCR);
- unsigned long host_tidr = mfspr(SPRN_TIDR);
- unsigned long host_iamr = mfspr(SPRN_IAMR);
- unsigned long host_amr = mfspr(SPRN_AMR);
- unsigned long host_fscr = mfspr(SPRN_FSCR);
+ struct p9_host_os_sprs host_os_sprs;
s64 dec;
u64 tb, next_timer;
int trap, save_pmu;
@@ -3484,6 +3563,8 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
vcpu->arch.ceded = 0;
+ save_p9_host_os_sprs(&host_os_sprs);
+
kvmhv_save_host_pmu(); /* saves it to PACA kvm_hstate */
kvmppc_subcore_enter_guest();
@@ -3511,28 +3592,7 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
#endif
mtspr(SPRN_VRSAVE, vcpu->arch.vrsave);
- mtspr(SPRN_DSCR, vcpu->arch.dscr);
- mtspr(SPRN_IAMR, vcpu->arch.iamr);
- mtspr(SPRN_PSPB, vcpu->arch.pspb);
- mtspr(SPRN_FSCR, vcpu->arch.fscr);
- mtspr(SPRN_TAR, vcpu->arch.tar);
- mtspr(SPRN_EBBHR, vcpu->arch.ebbhr);
- mtspr(SPRN_EBBRR, vcpu->arch.ebbrr);
- mtspr(SPRN_BESCR, vcpu->arch.bescr);
- mtspr(SPRN_WORT, vcpu->arch.wort);
- mtspr(SPRN_TIDR, vcpu->arch.tid);
- mtspr(SPRN_AMR, vcpu->arch.amr);
- mtspr(SPRN_UAMOR, vcpu->arch.uamor);
-
- /*
- * DAR, DSISR, and for nested HV, SPRGs must be set with MSR[RI]
- * clear (or hstate set appropriately to catch those registers
- * being clobbered if we take a MCE or SRESET), so those are done
- * later.
- */
-
- if (!(vcpu->arch.ctrl & 1))
- mtspr(SPRN_CTRLT, mfspr(SPRN_CTRLF) & ~1);
+ load_spr_state(vcpu);
/*
* When setting DEC, we must always deal with irq_work_raise via NMI vs
@@ -3628,33 +3688,10 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
vcpu->arch.dec_expires = dec + tb;
vcpu->cpu = -1;
vcpu->arch.thread_cpu = -1;
- vcpu->arch.ctrl = mfspr(SPRN_CTRLF);
-
- vcpu->arch.iamr = mfspr(SPRN_IAMR);
- vcpu->arch.pspb = mfspr(SPRN_PSPB);
- vcpu->arch.fscr = mfspr(SPRN_FSCR);
- vcpu->arch.tar = mfspr(SPRN_TAR);
- vcpu->arch.ebbhr = mfspr(SPRN_EBBHR);
- vcpu->arch.ebbrr = mfspr(SPRN_EBBRR);
- vcpu->arch.bescr = mfspr(SPRN_BESCR);
- vcpu->arch.wort = mfspr(SPRN_WORT);
- vcpu->arch.tid = mfspr(SPRN_TIDR);
- vcpu->arch.amr = mfspr(SPRN_AMR);
- vcpu->arch.uamor = mfspr(SPRN_UAMOR);
- vcpu->arch.dscr = mfspr(SPRN_DSCR);
-
- mtspr(SPRN_PSPB, 0);
- mtspr(SPRN_WORT, 0);
- mtspr(SPRN_UAMOR, 0);
- mtspr(SPRN_DSCR, host_dscr);
- mtspr(SPRN_TIDR, host_tidr);
- mtspr(SPRN_IAMR, host_iamr);
- if (host_amr != vcpu->arch.amr)
- mtspr(SPRN_AMR, host_amr);
+ store_spr_state(vcpu);
- if (host_fscr != vcpu->arch.fscr)
- mtspr(SPRN_FSCR, host_fscr);
+ restore_p9_host_os_sprs(vcpu, &host_os_sprs);
msr_check_and_set(MSR_FP | MSR_VEC | MSR_VSX);
store_fp_state(&vcpu->arch.fp);
--
2.23.0
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