1 files changed, 302 insertions, 0 deletions

diff --git a/arch/powerpc/kernel/kvm_emul.S b/arch/powerpc/kernel/kvm_emul.S
new file mode 100644
index 000000000000..f2b1b2523e61
--- /dev/null
+++ b/arch/powerpc/kernel/kvm_emul.S
@@ -0,0 +1,302 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ * Copyright SUSE Linux Products GmbH 2010
+ *
+ * Authors: Alexander Graf <agraf@suse.de>
+ */
+
+#include <asm/ppc_asm.h>
+#include <asm/kvm_asm.h>
+#include <asm/reg.h>
+#include <asm/page.h>
+#include <asm/asm-offsets.h>
+
+/* Hypercall entry point. Will be patched with device tree instructions. */
+
+.global kvm_hypercall_start
+kvm_hypercall_start:
+        li      r3, -1
+        nop
+        nop
+        nop
+        blr
+
+#define KVM_MAGIC_PAGE          (-4096)
+
+#ifdef CONFIG_64BIT
+#define LL64(reg, offs, reg2)   ld      reg, (offs)(reg2)
+#define STL64(reg, offs, reg2)  std     reg, (offs)(reg2)
+#else
+#define LL64(reg, offs, reg2)   lwz     reg, (offs + 4)(reg2)
+#define STL64(reg, offs, reg2)  stw     reg, (offs + 4)(reg2)
+#endif
+
+#define SCRATCH_SAVE                                                    \
+        /* Enable critical section. We are critical if                  \
+           shared->critical == r1 */                                    \
+        STL64(r1, KVM_MAGIC_PAGE + KVM_MAGIC_CRITICAL, 0);              \
+                                                                        \
+        /* Save state */                                                \
+        PPC_STL r31, (KVM_MAGIC_PAGE + KVM_MAGIC_SCRATCH1)(0);          \
+        PPC_STL r30, (KVM_MAGIC_PAGE + KVM_MAGIC_SCRATCH2)(0);          \
+        mfcr    r31;                                                    \
+        stw     r31, (KVM_MAGIC_PAGE + KVM_MAGIC_SCRATCH3)(0);
+
+#define SCRATCH_RESTORE                                                 \
+        /* Restore state */                                             \
+        PPC_LL  r31, (KVM_MAGIC_PAGE + KVM_MAGIC_SCRATCH1)(0);          \
+        lwz     r30, (KVM_MAGIC_PAGE + KVM_MAGIC_SCRATCH3)(0);          \
+        mtcr    r30;                                                    \
+        PPC_LL  r30, (KVM_MAGIC_PAGE + KVM_MAGIC_SCRATCH2)(0);          \
+                                                                        \
+        /* Disable critical section. We are critical if                 \
+           shared->critical == r1 and r2 is always != r1 */             \
+        STL64(r2, KVM_MAGIC_PAGE + KVM_MAGIC_CRITICAL, 0);
+
+.global kvm_emulate_mtmsrd
+kvm_emulate_mtmsrd:
+
+        SCRATCH_SAVE
+
+        /* Put MSR & ~(MSR_EE|MSR_RI) in r31 */
+        LL64(r31, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0)
+        lis     r30, (~(MSR_EE | MSR_RI))@h
+        ori     r30, r30, (~(MSR_EE | MSR_RI))@l
+        and     r31, r31, r30
+
+        /* OR the register's (MSR_EE|MSR_RI) on MSR */
+kvm_emulate_mtmsrd_reg:
+        ori     r30, r0, 0
+        andi.   r30, r30, (MSR_EE|MSR_RI)
+        or      r31, r31, r30
+
+        /* Put MSR back into magic page */
+        STL64(r31, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0)
+
+        /* Check if we have to fetch an interrupt */
+        lwz     r31, (KVM_MAGIC_PAGE + KVM_MAGIC_INT)(0)
+        cmpwi   r31, 0
+        beq+    no_check
+
+        /* Check if we may trigger an interrupt */
+        andi.   r30, r30, MSR_EE
+        beq     no_check
+
+        SCRATCH_RESTORE
+
+        /* Nag hypervisor */
+kvm_emulate_mtmsrd_orig_ins:
+        tlbsync
+
+        b       kvm_emulate_mtmsrd_branch
+
+no_check:
+
+        SCRATCH_RESTORE
+
+        /* Go back to caller */
+kvm_emulate_mtmsrd_branch:
+        b       .
+kvm_emulate_mtmsrd_end:
+
+.global kvm_emulate_mtmsrd_branch_offs
+kvm_emulate_mtmsrd_branch_offs:
+        .long (kvm_emulate_mtmsrd_branch - kvm_emulate_mtmsrd) / 4
+
+.global kvm_emulate_mtmsrd_reg_offs
+kvm_emulate_mtmsrd_reg_offs:
+        .long (kvm_emulate_mtmsrd_reg - kvm_emulate_mtmsrd) / 4
+
+.global kvm_emulate_mtmsrd_orig_ins_offs
+kvm_emulate_mtmsrd_orig_ins_offs:
+        .long (kvm_emulate_mtmsrd_orig_ins - kvm_emulate_mtmsrd) / 4
+
+.global kvm_emulate_mtmsrd_len
+kvm_emulate_mtmsrd_len:
+        .long (kvm_emulate_mtmsrd_end - kvm_emulate_mtmsrd) / 4
+
+
+#define MSR_SAFE_BITS (MSR_EE | MSR_CE | MSR_ME | MSR_RI)
+#define MSR_CRITICAL_BITS ~MSR_SAFE_BITS
+
+.global kvm_emulate_mtmsr
+kvm_emulate_mtmsr:
+
+        SCRATCH_SAVE
+
+        /* Fetch old MSR in r31 */
+        LL64(r31, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0)
+
+        /* Find the changed bits between old and new MSR */
+kvm_emulate_mtmsr_reg1:
+        ori     r30, r0, 0
+        xor     r31, r30, r31
+
+        /* Check if we need to really do mtmsr */
+        LOAD_REG_IMMEDIATE(r30, MSR_CRITICAL_BITS)
+        and.    r31, r31, r30
+
+        /* No critical bits changed? Maybe we can stay in the guest. */
+        beq     maybe_stay_in_guest
+
+do_mtmsr:
+
+        SCRATCH_RESTORE
+
+        /* Just fire off the mtmsr if it's critical */
+kvm_emulate_mtmsr_orig_ins:
+        mtmsr   r0
+
+        b       kvm_emulate_mtmsr_branch
+
+maybe_stay_in_guest:
+
+        /* Get the target register in r30 */
+kvm_emulate_mtmsr_reg2:
+        ori     r30, r0, 0
+
+        /* Check if we have to fetch an interrupt */
+        lwz     r31, (KVM_MAGIC_PAGE + KVM_MAGIC_INT)(0)
+        cmpwi   r31, 0
+        beq+    no_mtmsr
+
+        /* Check if we may trigger an interrupt */
+        andi.   r31, r30, MSR_EE
+        beq     no_mtmsr
+
+        b       do_mtmsr
+
+no_mtmsr:
+
+        /* Put MSR into magic page because we don't call mtmsr */
+        STL64(r30, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0)
+
+        SCRATCH_RESTORE
+
+        /* Go back to caller */
+kvm_emulate_mtmsr_branch:
+        b       .
+kvm_emulate_mtmsr_end:
+
+.global kvm_emulate_mtmsr_branch_offs
+kvm_emulate_mtmsr_branch_offs:
+        .long (kvm_emulate_mtmsr_branch - kvm_emulate_mtmsr) / 4
+
+.global kvm_emulate_mtmsr_reg1_offs
+kvm_emulate_mtmsr_reg1_offs:
+        .long (kvm_emulate_mtmsr_reg1 - kvm_emulate_mtmsr) / 4
+
+.global kvm_emulate_mtmsr_reg2_offs
+kvm_emulate_mtmsr_reg2_offs:
+        .long (kvm_emulate_mtmsr_reg2 - kvm_emulate_mtmsr) / 4
+
+.global kvm_emulate_mtmsr_orig_ins_offs
+kvm_emulate_mtmsr_orig_ins_offs:
+        .long (kvm_emulate_mtmsr_orig_ins - kvm_emulate_mtmsr) / 4
+
+.global kvm_emulate_mtmsr_len
+kvm_emulate_mtmsr_len:
+        .long (kvm_emulate_mtmsr_end - kvm_emulate_mtmsr) / 4
+
+
+
+.global kvm_emulate_wrteei
+kvm_emulate_wrteei:
+
+        SCRATCH_SAVE
+
+        /* Fetch old MSR in r31 */
+        LL64(r31, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0)
+
+        /* Remove MSR_EE from old MSR */
+        li      r30, 0
+        ori     r30, r30, MSR_EE
+        andc    r31, r31, r30
+
+        /* OR new MSR_EE onto the old MSR */
+kvm_emulate_wrteei_ee:
+        ori     r31, r31, 0
+
+        /* Write new MSR value back */
+        STL64(r31, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0)
+
+        SCRATCH_RESTORE
+
+        /* Go back to caller */
+kvm_emulate_wrteei_branch:
+        b       .
+kvm_emulate_wrteei_end:
+
+.global kvm_emulate_wrteei_branch_offs
+kvm_emulate_wrteei_branch_offs:
+        .long (kvm_emulate_wrteei_branch - kvm_emulate_wrteei) / 4
+
+.global kvm_emulate_wrteei_ee_offs
+kvm_emulate_wrteei_ee_offs:
+        .long (kvm_emulate_wrteei_ee - kvm_emulate_wrteei) / 4
+
+.global kvm_emulate_wrteei_len
+kvm_emulate_wrteei_len:
+        .long (kvm_emulate_wrteei_end - kvm_emulate_wrteei) / 4
+
+
+.global kvm_emulate_mtsrin
+kvm_emulate_mtsrin:
+
+        SCRATCH_SAVE
+
+        LL64(r31, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0)
+        andi.   r31, r31, MSR_DR | MSR_IR
+        beq     kvm_emulate_mtsrin_reg1
+
+        SCRATCH_RESTORE
+
+kvm_emulate_mtsrin_orig_ins:
+        nop
+        b       kvm_emulate_mtsrin_branch
+
+kvm_emulate_mtsrin_reg1:
+        /* rX >> 26 */
+        rlwinm  r30,r0,6,26,29
+
+kvm_emulate_mtsrin_reg2:
+        stw     r0, (KVM_MAGIC_PAGE + KVM_MAGIC_SR)(r30)
+
+        SCRATCH_RESTORE
+
+        /* Go back to caller */
+kvm_emulate_mtsrin_branch:
+        b       .
+kvm_emulate_mtsrin_end:
+
+.global kvm_emulate_mtsrin_branch_offs
+kvm_emulate_mtsrin_branch_offs:
+        .long (kvm_emulate_mtsrin_branch - kvm_emulate_mtsrin) / 4
+
+.global kvm_emulate_mtsrin_reg1_offs
+kvm_emulate_mtsrin_reg1_offs:
+        .long (kvm_emulate_mtsrin_reg1 - kvm_emulate_mtsrin) / 4
+
+.global kvm_emulate_mtsrin_reg2_offs
+kvm_emulate_mtsrin_reg2_offs:
+        .long (kvm_emulate_mtsrin_reg2 - kvm_emulate_mtsrin) / 4
+
+.global kvm_emulate_mtsrin_orig_ins_offs
+kvm_emulate_mtsrin_orig_ins_offs:
+        .long (kvm_emulate_mtsrin_orig_ins - kvm_emulate_mtsrin) / 4
+
+.global kvm_emulate_mtsrin_len
+kvm_emulate_mtsrin_len:
+        .long (kvm_emulate_mtsrin_end - kvm_emulate_mtsrin) / 4