[PATCH v5 3/5] KVM: PPC: Book3s: Remove kvmppc_read_inst() function
From: Mihai Caraman <hidden>
Date: 2014-07-17 11:22:47
Also in:
kvm
Subsystem:
kernel virtual machine for powerpc (kvm/powerpc), linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Michael Ellerman, Linus Torvalds
In the context of replacing kvmppc_ld() function calls with a version of kvmppc_get_last_inst() which allow to fail, Alex Graf suggested this: "If we get EMULATE_AGAIN, we just have to make sure we go back into the guest. No need to inject an ISI into the guest - it'll do that all by itself. With an error returning kvmppc_get_last_inst we can just use completely get rid of kvmppc_read_inst() and only use kvmppc_get_last_inst() instead." As a intermediate step get rid of kvmppc_read_inst() and only use kvmppc_ld() instead. Signed-off-by: Mihai Caraman <redacted> --- v5: - make paired single emulation the unusual v4: - new patch arch/powerpc/kvm/book3s_pr.c | 91 ++++++++++++++++++-------------------------- 1 file changed, 37 insertions(+), 54 deletions(-)
diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c
index e40765f..02a983e 100644
--- a/arch/powerpc/kvm/book3s_pr.c
+++ b/arch/powerpc/kvm/book3s_pr.c@@ -710,42 +710,6 @@ static void kvmppc_giveup_fac(struct kvm_vcpu *vcpu, ulong fac) #endif } -static int kvmppc_read_inst(struct kvm_vcpu *vcpu) -{ - ulong srr0 = kvmppc_get_pc(vcpu); - u32 last_inst = kvmppc_get_last_inst(vcpu); - int ret; - - ret = kvmppc_ld(vcpu, &srr0, sizeof(u32), &last_inst, false); - if (ret == -ENOENT) { - ulong msr = kvmppc_get_msr(vcpu); - - msr = kvmppc_set_field(msr, 33, 33, 1); - msr = kvmppc_set_field(msr, 34, 36, 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; - } - - return EMULATE_DONE; -} - -static int kvmppc_check_ext(struct kvm_vcpu *vcpu, unsigned int exit_nr) -{ - - /* Need to do paired single emulation? */ - if (!(vcpu->arch.hflags & BOOK3S_HFLAG_PAIRED_SINGLE)) - return EMULATE_DONE; - - /* Read out the instruction */ - if (kvmppc_read_inst(vcpu) == EMULATE_DONE) - /* Need to emulate */ - return EMULATE_FAIL; - - return EMULATE_AGAIN; -} - /* Handle external providers (FPU, Altivec, VSX) */ static int kvmppc_handle_ext(struct kvm_vcpu *vcpu, unsigned int exit_nr, ulong msr)
@@ -1149,31 +1113,49 @@ program_interrupt: case BOOK3S_INTERRUPT_VSX: { int ext_msr = 0; + int emul; + ulong pc; + u32 last_inst; + + if (vcpu->arch.hflags & BOOK3S_HFLAG_PAIRED_SINGLE) { + /* Emulate the instruction */ + + pc = kvmppc_get_pc(vcpu); + last_inst = kvmppc_get_last_inst(vcpu); + emul = kvmppc_ld(vcpu, &pc, sizeof(u32), &last_inst, + false); + if (emul == EMULATE_DONE) + goto program_interrupt; + else + r = RESUME_GUEST; + } else { + /* Do paired single emulation */ - switch (exit_nr) { - case BOOK3S_INTERRUPT_FP_UNAVAIL: ext_msr = MSR_FP; break; - case BOOK3S_INTERRUPT_ALTIVEC: ext_msr = MSR_VEC; break; - case BOOK3S_INTERRUPT_VSX: ext_msr = MSR_VSX; break; - } + switch (exit_nr) { + case BOOK3S_INTERRUPT_FP_UNAVAIL: + ext_msr = MSR_FP; + break; + + case BOOK3S_INTERRUPT_ALTIVEC: + ext_msr = MSR_VEC; + break; + + case BOOK3S_INTERRUPT_VSX: + ext_msr = MSR_VSX; + break; + } - switch (kvmppc_check_ext(vcpu, exit_nr)) { - case EMULATE_DONE: - /* everything ok - let's enable the ext */ r = kvmppc_handle_ext(vcpu, exit_nr, ext_msr); - break; - case EMULATE_FAIL: - /* we need to emulate this instruction */ - goto program_interrupt; - break; - default: - /* nothing to worry about - go again */ - break; } break; } case BOOK3S_INTERRUPT_ALIGNMENT: - if (kvmppc_read_inst(vcpu) == EMULATE_DONE) { - u32 last_inst = kvmppc_get_last_inst(vcpu); + { + ulong pc = kvmppc_get_pc(vcpu); + u32 last_inst = kvmppc_get_last_inst(vcpu); + int emul = kvmppc_ld(vcpu, &pc, sizeof(u32), &last_inst, false); + + if (emul == EMULATE_DONE) { u32 dsisr; u64 dar;
@@ -1187,6 +1169,7 @@ program_interrupt: } r = RESUME_GUEST; break; + } #ifdef CONFIG_PPC_BOOK3S_64 case BOOK3S_INTERRUPT_FAC_UNAVAIL: kvmppc_handle_fac(vcpu, vcpu->arch.shadow_fscr >> 56);
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1.7.11.7