1 files changed, 100 insertions, 60 deletions

diff --git a/arch/powerpc/kvm/book3s_64_slb.S b/arch/powerpc/kvm/book3s_64_slb.S
index ecd237a03fd..35b76272218 100644
--- a/arch/powerpc/kvm/book3s_64_slb.S
+++ b/arch/powerpc/kvm/book3s_64_slb.S
@@ -31,7 +31,7 @@
 #define REBOLT_SLB_ENTRY(num) \
         ld      r10, SHADOW_SLB_ESID(num)(r11); \
         cmpdi   r10, 0; \
-        beq     slb_exit_skip_1; \
+        beq     slb_exit_skip_ ## num; \
         oris    r10, r10, SLB_ESID_V@h; \
         ld      r9, SHADOW_SLB_VSID(num)(r11); \
         slbmte  r9, r10; \
@@ -51,23 +51,21 @@ kvmppc_handler_trampoline_enter:
          *
          * MSR = ~IR|DR
          * R13 = PACA
+         * R1 = host R1
+         * R2 = host R2
          * R9 = guest IP
          * R10 = guest MSR
-         * R11 = free
-         * R12 = free
-         * PACA[PACA_EXMC + EX_R9] = guest R9
-         * PACA[PACA_EXMC + EX_R10] = guest R10
-         * PACA[PACA_EXMC + EX_R11] = guest R11
-         * PACA[PACA_EXMC + EX_R12] = guest R12
-         * PACA[PACA_EXMC + EX_R13] = guest R13
-         * PACA[PACA_EXMC + EX_CCR] = guest CR
-         * PACA[PACA_EXMC + EX_R3] = guest XER
+         * all other GPRS = free
+         * PACA[KVM_CR] = guest CR
+         * PACA[KVM_XER] = guest XER
          */
 
         mtsrr0  r9
         mtsrr1  r10
 
-        mtspr   SPRN_SPRG_SCRATCH0, r0
+        /* Activate guest mode, so faults get handled by KVM */
+        li      r11, KVM_GUEST_MODE_GUEST
+        stb     r11, PACA_KVM_IN_GUEST(r13)
 
         /* Remove LPAR shadow entries */
 
@@ -131,20 +129,27 @@ slb_do_enter:
 
         /* Enter guest */
 
-        mfspr   r0, SPRN_SPRG_SCRATCH0
-
-        ld      r9, (PACA_EXMC+EX_R9)(r13)
-        ld      r10, (PACA_EXMC+EX_R10)(r13)
-        ld      r12, (PACA_EXMC+EX_R12)(r13)
-
-        lwz     r11, (PACA_EXMC+EX_CCR)(r13)
+        ld      r0, (PACA_KVM_R0)(r13)
+        ld      r1, (PACA_KVM_R1)(r13)
+        ld      r2, (PACA_KVM_R2)(r13)
+        ld      r3, (PACA_KVM_R3)(r13)
+        ld      r4, (PACA_KVM_R4)(r13)
+        ld      r5, (PACA_KVM_R5)(r13)
+        ld      r6, (PACA_KVM_R6)(r13)
+        ld      r7, (PACA_KVM_R7)(r13)
+        ld      r8, (PACA_KVM_R8)(r13)
+        ld      r9, (PACA_KVM_R9)(r13)
+        ld      r10, (PACA_KVM_R10)(r13)
+        ld      r12, (PACA_KVM_R12)(r13)
+
+        lwz     r11, (PACA_KVM_CR)(r13)
         mtcr    r11
 
-        ld      r11, (PACA_EXMC+EX_R3)(r13)
+        ld      r11, (PACA_KVM_XER)(r13)
         mtxer   r11
 
-        ld      r11, (PACA_EXMC+EX_R11)(r13)
-        ld      r13, (PACA_EXMC+EX_R13)(r13)
+        ld      r11, (PACA_KVM_R11)(r13)
+        ld      r13, (PACA_KVM_R13)(r13)
 
         RFI
 kvmppc_handler_trampoline_enter_end:
@@ -162,28 +167,54 @@ kvmppc_handler_trampoline_exit:
 
         /* Register usage at this point:
          *
-         * SPRG_SCRATCH0 = guest R13
-         * R01           = host R1
-         * R02           = host R2
-         * R10           = guest PC
-         * R11           = guest MSR
-         * R12           = exit handler id
-         * R13           = PACA
-         * PACA.exmc.CCR  = guest CR
-         * PACA.exmc.R9  = guest R1
-         * PACA.exmc.R10 = guest R10
-         * PACA.exmc.R11 = guest R11
-         * PACA.exmc.R12 = guest R12
-         * PACA.exmc.R13 = guest R2
+         * SPRG_SCRATCH0     = guest R13
+         * R12               = exit handler id
+         * R13               = PACA
+         * PACA.KVM.SCRATCH0 = guest R12
+         * PACA.KVM.SCRATCH1 = guest CR
          *
          */
 
         /* Save registers */
 
-        std     r0, (PACA_EXMC+EX_SRR0)(r13)
-        std     r9, (PACA_EXMC+EX_R3)(r13)
-        std     r10, (PACA_EXMC+EX_LR)(r13)
-        std     r11, (PACA_EXMC+EX_DAR)(r13)
+        std     r0, PACA_KVM_R0(r13)
+        std     r1, PACA_KVM_R1(r13)
+        std     r2, PACA_KVM_R2(r13)
+        std     r3, PACA_KVM_R3(r13)
+        std     r4, PACA_KVM_R4(r13)
+        std     r5, PACA_KVM_R5(r13)
+        std     r6, PACA_KVM_R6(r13)
+        std     r7, PACA_KVM_R7(r13)
+        std     r8, PACA_KVM_R8(r13)
+        std     r9, PACA_KVM_R9(r13)
+        std     r10, PACA_KVM_R10(r13)
+        std     r11, PACA_KVM_R11(r13)
+
+        /* Restore R1/R2 so we can handle faults */
+        ld      r1, PACA_KVM_HOST_R1(r13)
+        ld      r2, PACA_KVM_HOST_R2(r13)
+
+        /* Save guest PC and MSR in GPRs */
+        mfsrr0  r3
+        mfsrr1  r4
+
+        /* Get scratch'ed off registers */
+        mfspr   r9, SPRN_SPRG_SCRATCH0
+        std     r9, PACA_KVM_R13(r13)
+
+        ld      r8, PACA_KVM_SCRATCH0(r13)
+        std     r8, PACA_KVM_R12(r13)
+
+        lwz     r7, PACA_KVM_SCRATCH1(r13)
+        stw     r7, PACA_KVM_CR(r13)
+
+        /* Save more register state  */
+
+        mfxer   r6
+        stw     r6, PACA_KVM_XER(r13)
+
+        mfdar   r5
+        mfdsisr r6
 
         /*
          * In order for us to easily get the last instruction,
@@ -202,17 +233,28 @@ kvmppc_handler_trampoline_exit:
 
 ld_last_inst:
         /* Save off the guest instruction we're at */
+
+        /* Set guest mode to 'jump over instruction' so if lwz faults
+         * we'll just continue at the next IP. */
+        li      r9, KVM_GUEST_MODE_SKIP
+        stb     r9, PACA_KVM_IN_GUEST(r13)
+
         /*    1) enable paging for data */
         mfmsr   r9
         ori     r11, r9, MSR_DR                 /* Enable paging for data */
         mtmsr   r11
         /*    2) fetch the instruction */
-        lwz     r0, 0(r10)
+        li      r0, KVM_INST_FETCH_FAILED       /* In case lwz faults */
+        lwz     r0, 0(r3)
         /*    3) disable paging again */
         mtmsr   r9
 
 no_ld_last_inst:
 
+        /* Unset guest mode */
+        li      r9, KVM_GUEST_MODE_NONE
+        stb     r9, PACA_KVM_IN_GUEST(r13)
+
         /* Restore bolted entries from the shadow and fix it along the way */
 
         /* We don't store anything in entry 0, so we don't need to take care of it */
@@ -233,29 +275,27 @@ no_ld_last_inst:
 
 slb_do_exit:
 
-        /* Restore registers */
-
-        ld      r11, (PACA_EXMC+EX_DAR)(r13)
-        ld      r10, (PACA_EXMC+EX_LR)(r13)
-        ld      r9, (PACA_EXMC+EX_R3)(r13)
-
-        /* Save last inst */
-        stw     r0, (PACA_EXMC+EX_LR)(r13)
-
-        /* Save DAR and DSISR before going to paged mode */
-        mfdar   r0
-        std     r0, (PACA_EXMC+EX_DAR)(r13)
-        mfdsisr r0
-        stw     r0, (PACA_EXMC+EX_DSISR)(r13)
+        /* Register usage at this point:
+         *
+         * R0         = guest last inst
+         * R1         = host R1
+         * R2         = host R2
+         * R3         = guest PC
+         * R4         = guest MSR
+         * R5         = guest DAR
+         * R6         = guest DSISR
+         * R12        = exit handler id
+         * R13        = PACA
+         * PACA.KVM.* = guest *
+         *
+         */
 
         /* RFI into the highmem handler */
-        mfmsr   r0
-        ori     r0, r0, MSR_IR|MSR_DR|MSR_RI    /* Enable paging */
-        mtsrr1  r0
-        ld      r0, PACASAVEDMSR(r13)           /* Highmem handler address */
-        mtsrr0  r0
-
-        mfspr   r0, SPRN_SPRG_SCRATCH0
+        mfmsr   r7
+        ori     r7, r7, MSR_IR|MSR_DR|MSR_RI    /* Enable paging */
+        mtsrr1  r7
+        ld      r8, PACA_KVM_VMHANDLER(r13)     /* Highmem handler address */
+        mtsrr0  r8
 
         RFI
 kvmppc_handler_trampoline_exit_end: