KVM: PPC: Make SLB switching code the new segment framework

We just introduced generic segment switching code that only needs to call
small macros to do the actual switching, but keeps most of the entry / exit
code generic.

So let's move the SLB switching code over to use this new mechanism.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>

2 files changed, 25 insertions, 160 deletions

diff --git a/arch/powerpc/kvm/book3s_64_slb.S b/arch/powerpc/kvm/book3s_64_slb.S
index 091967907954..04e7d3bbfe8b 100644
--- a/arch/powerpc/kvm/book3s_64_slb.S
+++ b/arch/powerpc/kvm/book3s_64_slb.S
@@ -44,8 +44,7 @@ slb_exit_skip_ ## num:
  *                                                                            *
  *****************************************************************************/
 
-.global kvmppc_handler_trampoline_enter
-kvmppc_handler_trampoline_enter:
+.macro LOAD_GUEST_SEGMENTS
 
         /* Required state:
          *
@@ -53,20 +52,14 @@ kvmppc_handler_trampoline_enter:
          * R13 = PACA
          * R1 = host R1
          * R2 = host R2
-         * R9 = guest IP
-         * R10 = guest MSR
-         * all other GPRS = free
-         * PACA[KVM_CR] = guest CR
-         * PACA[KVM_XER] = guest XER
+         * R3 = shadow vcpu
+         * all other volatile GPRS = free
+         * SVCPU[CR]  = guest CR
+         * SVCPU[XER] = guest XER
+         * SVCPU[CTR] = guest CTR
+         * SVCPU[LR]  = guest LR
          */
 
-        mtsrr0  r9
-        mtsrr1  r10
-
-        /* 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 */
 
 #if SLB_NUM_BOLTED == 3
@@ -101,14 +94,14 @@ kvmppc_handler_trampoline_enter:
 
         /* Fill SLB with our shadow */
 
-        lbz     r12, PACA_KVM_SLB_MAX(r13)
+        lbz     r12, SVCPU_SLB_MAX(r3)
         mulli   r12, r12, 16
-        addi    r12, r12, PACA_KVM_SLB
-        add     r12, r12, r13
+        addi    r12, r12, SVCPU_SLB
+        add     r12, r12, r3
 
         /* for (r11 = kvm_slb; r11 < kvm_slb + kvm_slb_size; r11+=slb_entry) */
-        li      r11, PACA_KVM_SLB
-        add     r11, r11, r13
+        li      r11, SVCPU_SLB
+        add     r11, r11, r3
 
 slb_loop_enter:
 
@@ -127,34 +120,7 @@ slb_loop_enter_skip:
 
 slb_do_enter:
 
-        /* Enter guest */
-
-        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
-
-        lwz     r11, (PACA_KVM_XER)(r13)
-        mtxer   r11
-
-        ld      r11, (PACA_KVM_R11)(r13)
-        ld      r13, (PACA_KVM_R13)(r13)
-
-        RFI
-kvmppc_handler_trampoline_enter_end:
-
-
+.endm
 
 /******************************************************************************
  *                                                                            *
@@ -162,99 +128,22 @@ kvmppc_handler_trampoline_enter_end:
  *                                                                            *
  *****************************************************************************/
 
-.global kvmppc_handler_trampoline_exit
-kvmppc_handler_trampoline_exit:
+.macro LOAD_HOST_SEGMENTS
 
         /* Register usage at this point:
          *
-         * SPRG_SCRATCH0     = guest R13
-         * R12               = exit handler id
-         * R13               = PACA
-         * PACA.KVM.SCRATCH0 = guest R12
-         * PACA.KVM.SCRATCH1 = guest CR
+         * R1         = host R1
+         * R2         = host R2
+         * R12        = exit handler id
+         * R13        = shadow vcpu - SHADOW_VCPU_OFF [=PACA on PPC64]
+         * SVCPU.*    = guest *
+         * SVCPU[CR]  = guest CR
+         * SVCPU[XER] = guest XER
+         * SVCPU[CTR] = guest CTR
+         * SVCPU[LR]  = guest LR
          *
          */
 
-        /* Save registers */
-
-        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,
-         * we got the #vmexit at, we exploit the fact that the
-         * virtual layout is still the same here, so we can just
-         * ld from the guest's PC address
-         */
-
-        /* We only load the last instruction when it's safe */
-        cmpwi   r12, BOOK3S_INTERRUPT_DATA_STORAGE
-        beq     ld_last_inst
-        cmpwi   r12, BOOK3S_INTERRUPT_PROGRAM
-        beq     ld_last_inst
-
-        b       no_ld_last_inst
-
-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 */
-        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 */
@@ -275,28 +164,4 @@ no_ld_last_inst:
 
 slb_do_exit:
 
-        /* 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   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:
-
+.endm
diff --git a/arch/powerpc/kvm/book3s_rmhandlers.S b/arch/powerpc/kvm/book3s_rmhandlers.S
index 284f0a03891f..8a1c4bdb58b3 100644
--- a/arch/powerpc/kvm/book3s_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_rmhandlers.S
@@ -248,4 +248,4 @@ kvmppc_trampoline_lowmem:
 kvmppc_trampoline_enter:
         .long kvmppc_handler_trampoline_enter - _stext
 
-#include "book3s_64_slb.S"
+#include "book3s_segment.S"