ARM: KVM: Remove the old world switch
As we now have a full reimplementation of the world switch, it is
time to kiss the old stuff goodbye. I'm not sure we'll miss it.
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
diff --git a/arch/arm/kvm/interrupts.S b/arch/arm/kvm/interrupts.S
index 01eb169..b1bd316 100644
--- a/arch/arm/kvm/interrupts.S
+++ b/arch/arm/kvm/interrupts.S
@@ -17,198 +17,8 @@
*/
#include <linux/linkage.h>
-#include <linux/const.h>
-#include <asm/unified.h>
-#include <asm/page.h>
-#include <asm/ptrace.h>
-#include <asm/asm-offsets.h>
-#include <asm/kvm_asm.h>
-#include <asm/kvm_arm.h>
-#include <asm/vfpmacros.h>
-#include "interrupts_head.S"
.text
- .pushsection .hyp.text, "ax"
-
-/********************************************************************
- * Flush per-VMID TLBs
- *
- * void __kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa);
- *
- * We rely on the hardware to broadcast the TLB invalidation to all CPUs
- * inside the inner-shareable domain (which is the case for all v7
- * implementations). If we come across a non-IS SMP implementation, we'll
- * have to use an IPI based mechanism. Until then, we stick to the simple
- * hardware assisted version.
- *
- * As v7 does not support flushing per IPA, just nuke the whole TLB
- * instead, ignoring the ipa value.
- */
-ENTRY(__kvm_tlb_flush_vmid_ipa)
- push {r2, r3}
-
- dsb ishst
- add r0, r0, #KVM_VTTBR
- ldrd r2, r3, [r0]
- mcrr p15, 6, rr_lo_hi(r2, r3), c2 @ Write VTTBR
- isb
- mcr p15, 0, r0, c8, c3, 0 @ TLBIALLIS (rt ignored)
- dsb ish
- isb
- mov r2, #0
- mov r3, #0
- mcrr p15, 6, r2, r3, c2 @ Back to VMID #0
- isb @ Not necessary if followed by eret
-
- pop {r2, r3}
- bx lr
-ENDPROC(__kvm_tlb_flush_vmid_ipa)
-
-/**
- * void __kvm_tlb_flush_vmid(struct kvm *kvm) - Flush per-VMID TLBs
- *
- * Reuses __kvm_tlb_flush_vmid_ipa() for ARMv7, without passing address
- * parameter
- */
-
-ENTRY(__kvm_tlb_flush_vmid)
- b __kvm_tlb_flush_vmid_ipa
-ENDPROC(__kvm_tlb_flush_vmid)
-
-/********************************************************************
- * Flush TLBs and instruction caches of all CPUs inside the inner-shareable
- * domain, for all VMIDs
- *
- * void __kvm_flush_vm_context(void);
- */
-ENTRY(__kvm_flush_vm_context)
- mov r0, #0 @ rn parameter for c15 flushes is SBZ
-
- /* Invalidate NS Non-Hyp TLB Inner Shareable (TLBIALLNSNHIS) */
- mcr p15, 4, r0, c8, c3, 4
- /* Invalidate instruction caches Inner Shareable (ICIALLUIS) */
- mcr p15, 0, r0, c7, c1, 0
- dsb ish
- isb @ Not necessary if followed by eret
-
- bx lr
-ENDPROC(__kvm_flush_vm_context)
-
-
-/********************************************************************
- * Hypervisor world-switch code
- *
- *
- * int __kvm_vcpu_run(struct kvm_vcpu *vcpu)
- */
-ENTRY(__kvm_vcpu_run)
- @ Save the vcpu pointer
- mcr p15, 4, vcpu, c13, c0, 2 @ HTPIDR
-
- save_host_regs
-
- restore_vgic_state
- restore_timer_state
-
- @ Store hardware CP15 state and load guest state
- read_cp15_state store_to_vcpu = 0
- write_cp15_state read_from_vcpu = 1
-
- @ If the host kernel has not been configured with VFPv3 support,
- @ then it is safer if we deny guests from using it as well.
-#ifdef CONFIG_VFPv3
- @ Set FPEXC_EN so the guest doesn't trap floating point instructions
- VFPFMRX r2, FPEXC @ VMRS
- push {r2}
- orr r2, r2, #FPEXC_EN
- VFPFMXR FPEXC, r2 @ VMSR
-#endif
-
- @ Configure Hyp-role
- configure_hyp_role vmentry
-
- @ Trap coprocessor CRx accesses
- set_hstr vmentry
- set_hcptr vmentry, (HCPTR_TTA | HCPTR_TCP(10) | HCPTR_TCP(11))
- set_hdcr vmentry
-
- @ Write configured ID register into MIDR alias
- ldr r1, [vcpu, #VCPU_MIDR]
- mcr p15, 4, r1, c0, c0, 0
-
- @ Write guest view of MPIDR into VMPIDR
- ldr r1, [vcpu, #CP15_OFFSET(c0_MPIDR)]
- mcr p15, 4, r1, c0, c0, 5
-
- @ Set up guest memory translation
- ldr r1, [vcpu, #VCPU_KVM]
- add r1, r1, #KVM_VTTBR
- ldrd r2, r3, [r1]
- mcrr p15, 6, rr_lo_hi(r2, r3), c2 @ Write VTTBR
-
- @ We're all done, just restore the GPRs and go to the guest
- restore_guest_regs
- clrex @ Clear exclusive monitor
- eret
-
-__kvm_vcpu_return:
- /*
- * return convention:
- * guest r0, r1, r2 saved on the stack
- * r0: vcpu pointer
- * r1: exception code
- */
- save_guest_regs
-
- @ Set VMID == 0
- mov r2, #0
- mov r3, #0
- mcrr p15, 6, r2, r3, c2 @ Write VTTBR
-
- @ Don't trap coprocessor accesses for host kernel
- set_hstr vmexit
- set_hdcr vmexit
- set_hcptr vmexit, (HCPTR_TTA | HCPTR_TCP(10) | HCPTR_TCP(11)), after_vfp_restore
-
-#ifdef CONFIG_VFPv3
- @ Switch VFP/NEON hardware state to the host's
- add r7, vcpu, #(VCPU_GUEST_CTXT + CPU_CTXT_VFP)
- store_vfp_state r7
- add r7, vcpu, #VCPU_HOST_CTXT
- ldr r7, [r7]
- add r7, r7, #CPU_CTXT_VFP
- restore_vfp_state r7
-
-after_vfp_restore:
- @ Restore FPEXC_EN which we clobbered on entry
- pop {r2}
- VFPFMXR FPEXC, r2
-#else
-after_vfp_restore:
-#endif
-
- @ Reset Hyp-role
- configure_hyp_role vmexit
-
- @ Let host read hardware MIDR
- mrc p15, 0, r2, c0, c0, 0
- mcr p15, 4, r2, c0, c0, 0
-
- @ Back to hardware MPIDR
- mrc p15, 0, r2, c0, c0, 5
- mcr p15, 4, r2, c0, c0, 5
-
- @ Store guest CP15 state and restore host state
- read_cp15_state store_to_vcpu = 1
- write_cp15_state read_from_vcpu = 0
-
- save_timer_state
- save_vgic_state
-
- restore_host_regs
- clrex @ Clear exclusive monitor
- mov r0, r1 @ Return the return code
- bx lr @ return to IOCTL
/********************************************************************
* Call function in Hyp mode
@@ -239,281 +49,4 @@
ENTRY(kvm_call_hyp)
hvc #0
bx lr
-
-/********************************************************************
- * Hypervisor exception vector and handlers
- *
- *
- * The KVM/ARM Hypervisor ABI is defined as follows:
- *
- * Entry to Hyp mode from the host kernel will happen _only_ when an HVC
- * instruction is issued since all traps are disabled when running the host
- * kernel as per the Hyp-mode initialization at boot time.
- *
- * HVC instructions cause a trap to the vector page + offset 0x14 (see hyp_hvc
- * below) when the HVC instruction is called from SVC mode (i.e. a guest or the
- * host kernel) and they cause a trap to the vector page + offset 0x8 when HVC
- * instructions are called from within Hyp-mode.
- *
- * Hyp-ABI: Calling HYP-mode functions from host (in SVC mode):
- * Switching to Hyp mode is done through a simple HVC #0 instruction. The
- * exception vector code will check that the HVC comes from VMID==0 and if
- * so will push the necessary state (SPSR, lr_usr) on the Hyp stack.
- * - r0 contains a pointer to a HYP function
- * - r1, r2, and r3 contain arguments to the above function.
- * - The HYP function will be called with its arguments in r0, r1 and r2.
- * On HYP function return, we return directly to SVC.
- *
- * Note that the above is used to execute code in Hyp-mode from a host-kernel
- * point of view, and is a different concept from performing a world-switch and
- * executing guest code SVC mode (with a VMID != 0).
- */
-
-/* Handle undef, svc, pabt, or dabt by crashing with a user notice */
-.macro bad_exception exception_code, panic_str
- push {r0-r2}
- mrrc p15, 6, r0, r1, c2 @ Read VTTBR
- lsr r1, r1, #16
- ands r1, r1, #0xff
- beq 99f
-
- load_vcpu @ Load VCPU pointer
- .if \exception_code == ARM_EXCEPTION_DATA_ABORT
- mrc p15, 4, r2, c5, c2, 0 @ HSR
- mrc p15, 4, r1, c6, c0, 0 @ HDFAR
- str r2, [vcpu, #VCPU_HSR]
- str r1, [vcpu, #VCPU_HxFAR]
- .endif
- .if \exception_code == ARM_EXCEPTION_PREF_ABORT
- mrc p15, 4, r2, c5, c2, 0 @ HSR
- mrc p15, 4, r1, c6, c0, 2 @ HIFAR
- str r2, [vcpu, #VCPU_HSR]
- str r1, [vcpu, #VCPU_HxFAR]
- .endif
- mov r1, #\exception_code
- b __kvm_vcpu_return
-
- @ We were in the host already. Let's craft a panic-ing return to SVC.
-99: mrs r2, cpsr
- bic r2, r2, #MODE_MASK
- orr r2, r2, #SVC_MODE
-THUMB( orr r2, r2, #PSR_T_BIT )
- msr spsr_cxsf, r2
- mrs r1, ELR_hyp
- ldr r2, =panic
- msr ELR_hyp, r2
- ldr r0, =\panic_str
- clrex @ Clear exclusive monitor
- eret
-.endm
-
- .align 5
-__kvm_hyp_vector:
- .globl __kvm_hyp_vector
-
- @ Hyp-mode exception vector
- W(b) hyp_reset
- W(b) hyp_undef
- W(b) hyp_svc
- W(b) hyp_pabt
- W(b) hyp_dabt
- W(b) hyp_hvc
- W(b) hyp_irq
- W(b) hyp_fiq
-
- .align
-hyp_reset:
- b hyp_reset
-
- .align
-hyp_undef:
- bad_exception ARM_EXCEPTION_UNDEFINED, und_die_str
-
- .align
-hyp_svc:
- bad_exception ARM_EXCEPTION_HVC, svc_die_str
-
- .align
-hyp_pabt:
- bad_exception ARM_EXCEPTION_PREF_ABORT, pabt_die_str
-
- .align
-hyp_dabt:
- bad_exception ARM_EXCEPTION_DATA_ABORT, dabt_die_str
-
- .align
-hyp_hvc:
- /*
- * Getting here is either becuase of a trap from a guest or from calling
- * HVC from the host kernel, which means "switch to Hyp mode".
- */
- push {r0, r1, r2}
-
- @ Check syndrome register
- mrc p15, 4, r1, c5, c2, 0 @ HSR
- lsr r0, r1, #HSR_EC_SHIFT
- cmp r0, #HSR_EC_HVC
- bne guest_trap @ Not HVC instr.
-
- /*
- * Let's check if the HVC came from VMID 0 and allow simple
- * switch to Hyp mode
- */
- mrrc p15, 6, r0, r2, c2
- lsr r2, r2, #16
- and r2, r2, #0xff
- cmp r2, #0
- bne guest_trap @ Guest called HVC
-
- /*
- * Getting here means host called HVC, we shift parameters and branch
- * to Hyp function.
- */
- pop {r0, r1, r2}
-
- /* Check for __hyp_get_vectors */
- cmp r0, #-1
- mrceq p15, 4, r0, c12, c0, 0 @ get HVBAR
- beq 1f
-
- push {lr}
- mrs lr, SPSR
- push {lr}
-
- mov lr, r0
- mov r0, r1
- mov r1, r2
- mov r2, r3
-
-THUMB( orr lr, #1)
- blx lr @ Call the HYP function
-
- pop {lr}
- msr SPSR_csxf, lr
- pop {lr}
-1: eret
-
-guest_trap:
- load_vcpu @ Load VCPU pointer to r0
- str r1, [vcpu, #VCPU_HSR]
-
- @ Check if we need the fault information
- lsr r1, r1, #HSR_EC_SHIFT
-#ifdef CONFIG_VFPv3
- cmp r1, #HSR_EC_CP_0_13
- beq switch_to_guest_vfp
-#endif
- cmp r1, #HSR_EC_IABT
- mrceq p15, 4, r2, c6, c0, 2 @ HIFAR
- beq 2f
- cmp r1, #HSR_EC_DABT
- bne 1f
- mrc p15, 4, r2, c6, c0, 0 @ HDFAR
-
-2: str r2, [vcpu, #VCPU_HxFAR]
-
- /*
- * B3.13.5 Reporting exceptions taken to the Non-secure PL2 mode:
- *
- * Abort on the stage 2 translation for a memory access from a
- * Non-secure PL1 or PL0 mode:
- *
- * For any Access flag fault or Translation fault, and also for any
- * Permission fault on the stage 2 translation of a memory access
- * made as part of a translation table walk for a stage 1 translation,
- * the HPFAR holds the IPA that caused the fault. Otherwise, the HPFAR
- * is UNKNOWN.
- */
-
- /* Check for permission fault, and S1PTW */
- mrc p15, 4, r1, c5, c2, 0 @ HSR
- and r0, r1, #HSR_FSC_TYPE
- cmp r0, #FSC_PERM
- tsteq r1, #(1 << 7) @ S1PTW
- mrcne p15, 4, r2, c6, c0, 4 @ HPFAR
- bne 3f
-
- /* Preserve PAR */
- mrrc p15, 0, r0, r1, c7 @ PAR
- push {r0, r1}
-
- /* Resolve IPA using the xFAR */
- mcr p15, 0, r2, c7, c8, 0 @ ATS1CPR
- isb
- mrrc p15, 0, r0, r1, c7 @ PAR
- tst r0, #1
- bne 4f @ Failed translation
- ubfx r2, r0, #12, #20
- lsl r2, r2, #4
- orr r2, r2, r1, lsl #24
-
- /* Restore PAR */
- pop {r0, r1}
- mcrr p15, 0, r0, r1, c7 @ PAR
-
-3: load_vcpu @ Load VCPU pointer to r0
- str r2, [r0, #VCPU_HPFAR]
-
-1: mov r1, #ARM_EXCEPTION_HVC
- b __kvm_vcpu_return
-
-4: pop {r0, r1} @ Failed translation, return to guest
- mcrr p15, 0, r0, r1, c7 @ PAR
- clrex
- pop {r0, r1, r2}
- eret
-
-/*
- * If VFPv3 support is not available, then we will not switch the VFP
- * registers; however cp10 and cp11 accesses will still trap and fallback
- * to the regular coprocessor emulation code, which currently will
- * inject an undefined exception to the guest.
- */
-#ifdef CONFIG_VFPv3
-switch_to_guest_vfp:
- push {r3-r7}
-
- @ NEON/VFP used. Turn on VFP access.
- set_hcptr vmtrap, (HCPTR_TCP(10) | HCPTR_TCP(11))
-
- @ Switch VFP/NEON hardware state to the guest's
- add r7, r0, #VCPU_HOST_CTXT
- ldr r7, [r7]
- add r7, r7, #CPU_CTXT_VFP
- store_vfp_state r7
- add r7, r0, #(VCPU_GUEST_CTXT + CPU_CTXT_VFP)
- restore_vfp_state r7
-
- pop {r3-r7}
- pop {r0-r2}
- clrex
- eret
-#endif
-
- .align
-hyp_irq:
- push {r0, r1, r2}
- mov r1, #ARM_EXCEPTION_IRQ
- load_vcpu @ Load VCPU pointer to r0
- b __kvm_vcpu_return
-
- .align
-hyp_fiq:
- b hyp_fiq
-
- .ltorg
-
- .popsection
-
- .pushsection ".rodata"
-
-und_die_str:
- .ascii "unexpected undefined exception in Hyp mode at: %#08x\n"
-pabt_die_str:
- .ascii "unexpected prefetch abort in Hyp mode at: %#08x\n"
-dabt_die_str:
- .ascii "unexpected data abort in Hyp mode at: %#08x\n"
-svc_die_str:
- .ascii "unexpected HVC/SVC trap in Hyp mode at: %#08x\n"
-
- .popsection
+ENDPROC(kvm_call_hyp)