This patch is part of a series which builds KVM's non-VHE hyp code separately
from VHE and the rest of the kernel.

tlb.c contains code for flushing the TLB, with parts shared between VHE/nVHE.
These common routines are moved into a header file tlb.h, VHE-specific code
remains in tlb.c and nVHE-specific code is moved to nvhe/tlb.c.

The header file expects its users to implement two helper functions declared
at the top of the file.

Signed-off-by: David Brazdil <dbraz...@google.com>
---
 arch/arm64/kernel/image-vars.h   |   8 +-
 arch/arm64/kvm/hyp/nvhe/Makefile |   2 +-
 arch/arm64/kvm/hyp/nvhe/tlb.c    |  69 +++++++++++++
 arch/arm64/kvm/hyp/tlb.c         | 170 +++----------------------------
 arch/arm64/kvm/hyp/tlb.h         | 129 +++++++++++++++++++++++
 5 files changed, 216 insertions(+), 162 deletions(-)
 create mode 100644 arch/arm64/kvm/hyp/nvhe/tlb.c
 create mode 100644 arch/arm64/kvm/hyp/tlb.h

diff --git a/arch/arm64/kernel/image-vars.h b/arch/arm64/kernel/image-vars.h
index 59c53566eceb..c0a0ec238854 100644
--- a/arch/arm64/kernel/image-vars.h
+++ b/arch/arm64/kernel/image-vars.h
@@ -62,14 +62,11 @@ __efistub__ctype            = _ctype;
  */
 
 __hyp_text___guest_exit = __guest_exit;
+__hyp_text___icache_flags = __icache_flags;
 __hyp_text___kvm_enable_ssbs = __kvm_enable_ssbs;
-__hyp_text___kvm_flush_vm_context = __kvm_flush_vm_context;
 __hyp_text___kvm_get_mdcr_el2 = __kvm_get_mdcr_el2;
 __hyp_text___kvm_handle_stub_hvc = __kvm_handle_stub_hvc;
 __hyp_text___kvm_timer_set_cntvoff = __kvm_timer_set_cntvoff;
-__hyp_text___kvm_tlb_flush_local_vmid = __kvm_tlb_flush_local_vmid;
-__hyp_text___kvm_tlb_flush_vmid = __kvm_tlb_flush_vmid;
-__hyp_text___kvm_tlb_flush_vmid_ipa = __kvm_tlb_flush_vmid_ipa;
 __hyp_text___kvm_vcpu_run_nvhe = __kvm_vcpu_run_nvhe;
 __hyp_text___vgic_v3_get_ich_vtr_el2 = __vgic_v3_get_ich_vtr_el2;
 __hyp_text___vgic_v3_init_lrs = __vgic_v3_init_lrs;
@@ -79,8 +76,11 @@ __hyp_text___vgic_v3_save_aprs = __vgic_v3_save_aprs;
 __hyp_text___vgic_v3_write_vmcr = __vgic_v3_write_vmcr;
 __hyp_text_abort_guest_exit_end = abort_guest_exit_end;
 __hyp_text_abort_guest_exit_start = abort_guest_exit_start;
+__hyp_text_arm64_const_caps_ready = arm64_const_caps_ready;
 __hyp_text_arm64_enable_wa2_handling = arm64_enable_wa2_handling;
 __hyp_text_arm64_ssbd_callback_required = arm64_ssbd_callback_required;
+__hyp_text_cpu_hwcap_keys = cpu_hwcap_keys;
+__hyp_text_cpu_hwcaps = cpu_hwcaps;
 __hyp_text_hyp_panic = hyp_panic;
 __hyp_text_kimage_voffset = kimage_voffset;
 __hyp_text_kvm_host_data = kvm_host_data;
diff --git a/arch/arm64/kvm/hyp/nvhe/Makefile b/arch/arm64/kvm/hyp/nvhe/Makefile
index fa20b2723652..0da836cb5580 100644
--- a/arch/arm64/kvm/hyp/nvhe/Makefile
+++ b/arch/arm64/kvm/hyp/nvhe/Makefile
@@ -7,7 +7,7 @@ asflags-y := -D__HYPERVISOR__
 ccflags-y := -D__HYPERVISOR__ -fno-stack-protector -DDISABLE_BRANCH_PROFILING \
             $(DISABLE_STACKLEAK_PLUGIN)
 
-obj-y := host_hypercall.o ../hyp-entry.o
+obj-y := tlb.o host_hypercall.o ../hyp-entry.o
 
 obj-y := $(patsubst %.o,%.hyp.o,$(obj-y))
 extra-y := $(patsubst %.hyp.o,%.hyp.tmp.o,$(obj-y))
diff --git a/arch/arm64/kvm/hyp/nvhe/tlb.c b/arch/arm64/kvm/hyp/nvhe/tlb.c
new file mode 100644
index 000000000000..1b8f4000f98c
--- /dev/null
+++ b/arch/arm64/kvm/hyp/nvhe/tlb.c
@@ -0,0 +1,69 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2015 - ARM Ltd
+ * Author: Marc Zyngier <marc.zyng...@arm.com>
+ */
+
+#include <linux/irqflags.h>
+
+#include <asm/kvm_hyp.h>
+#include <asm/kvm_mmu.h>
+#include <asm/tlbflush.h>
+
+#include "../tlb.h"
+
+static void __hyp_text __tlb_switch_to_guest(struct kvm *kvm,
+                                            struct tlb_inv_context *cxt)
+{
+       if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT_NVHE)) {
+               u64 val;
+
+               /*
+                * For CPUs that are affected by ARM 1319367, we need to
+                * avoid a host Stage-1 walk while we have the guest's
+                * VMID set in the VTTBR in order to invalidate TLBs.
+                * We're guaranteed that the S1 MMU is enabled, so we can
+                * simply set the EPD bits to avoid any further TLB fill.
+                */
+               val = cxt->tcr = read_sysreg_el1(SYS_TCR);
+               val |= TCR_EPD1_MASK | TCR_EPD0_MASK;
+               write_sysreg_el1(val, SYS_TCR);
+               isb();
+       }
+
+       __load_guest_stage2(kvm);
+       isb();
+}
+
+static void __hyp_text __tlb_switch_to_host(struct kvm *kvm,
+                                           struct tlb_inv_context *cxt)
+{
+       write_sysreg(0, vttbr_el2);
+
+       if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT_NVHE)) {
+               /* Ensure write of the host VMID */
+               isb();
+               /* Restore the host's TCR_EL1 */
+               write_sysreg_el1(cxt->tcr, SYS_TCR);
+       }
+}
+
+void __hyp_text __kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa)
+{
+       __tlb_flush_vmid_ipa(kvm, ipa);
+}
+
+void __hyp_text __kvm_tlb_flush_vmid(struct kvm *kvm)
+{
+       __tlb_flush_vmid(kvm);
+}
+
+void __hyp_text __kvm_tlb_flush_local_vmid(struct kvm_vcpu *vcpu)
+{
+       __tlb_flush_local_vmid(vcpu);
+}
+
+void __hyp_text __kvm_flush_vm_context(void)
+{
+       __tlb_flush_vm_context();
+}
diff --git a/arch/arm64/kvm/hyp/tlb.c b/arch/arm64/kvm/hyp/tlb.c
index ceaddbe4279f..ab55b0c4a80c 100644
--- a/arch/arm64/kvm/hyp/tlb.c
+++ b/arch/arm64/kvm/hyp/tlb.c
@@ -10,14 +10,10 @@
 #include <asm/kvm_mmu.h>
 #include <asm/tlbflush.h>
 
-struct tlb_inv_context {
-       unsigned long   flags;
-       u64             tcr;
-       u64             sctlr;
-};
+#include "tlb.h"
 
-static void __hyp_text __tlb_switch_to_guest_vhe(struct kvm *kvm,
-                                                struct tlb_inv_context *cxt)
+static void __hyp_text __tlb_switch_to_guest(struct kvm *kvm,
+                                            struct tlb_inv_context *cxt)
 {
        u64 val;
 
@@ -60,40 +56,8 @@ static void __hyp_text __tlb_switch_to_guest_vhe(struct kvm 
*kvm,
        isb();
 }
 
-static void __hyp_text __tlb_switch_to_guest_nvhe(struct kvm *kvm,
-                                                 struct tlb_inv_context *cxt)
-{
-       if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT_NVHE)) {
-               u64 val;
-
-               /*
-                * For CPUs that are affected by ARM 1319367, we need to
-                * avoid a host Stage-1 walk while we have the guest's
-                * VMID set in the VTTBR in order to invalidate TLBs.
-                * We're guaranteed that the S1 MMU is enabled, so we can
-                * simply set the EPD bits to avoid any further TLB fill.
-                */
-               val = cxt->tcr = read_sysreg_el1(SYS_TCR);
-               val |= TCR_EPD1_MASK | TCR_EPD0_MASK;
-               write_sysreg_el1(val, SYS_TCR);
-               isb();
-       }
-
-       __load_guest_stage2(kvm);
-       isb();
-}
-
-static void __hyp_text __tlb_switch_to_guest(struct kvm *kvm,
-                                            struct tlb_inv_context *cxt)
-{
-       if (has_vhe())
-               __tlb_switch_to_guest_vhe(kvm, cxt);
-       else
-               __tlb_switch_to_guest_nvhe(kvm, cxt);
-}
-
-static void __hyp_text __tlb_switch_to_host_vhe(struct kvm *kvm,
-                                               struct tlb_inv_context *cxt)
+static void __hyp_text __tlb_switch_to_host(struct kvm *kvm,
+                                           struct tlb_inv_context *cxt)
 {
        /*
         * We're done with the TLB operation, let's restore the host's
@@ -112,130 +76,22 @@ static void __hyp_text __tlb_switch_to_host_vhe(struct 
kvm *kvm,
        local_irq_restore(cxt->flags);
 }
 
-static void __hyp_text __tlb_switch_to_host_nvhe(struct kvm *kvm,
-                                                struct tlb_inv_context *cxt)
+void __kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa)
 {
-       write_sysreg(0, vttbr_el2);
-
-       if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT_NVHE)) {
-               /* Ensure write of the host VMID */
-               isb();
-               /* Restore the host's TCR_EL1 */
-               write_sysreg_el1(cxt->tcr, SYS_TCR);
-       }
+       __tlb_flush_vmid_ipa(kvm, ipa);
 }
 
-static void __hyp_text __tlb_switch_to_host(struct kvm *kvm,
-                                           struct tlb_inv_context *cxt)
+void __kvm_tlb_flush_vmid(struct kvm *kvm)
 {
-       if (has_vhe())
-               __tlb_switch_to_host_vhe(kvm, cxt);
-       else
-               __tlb_switch_to_host_nvhe(kvm, cxt);
+       __tlb_flush_vmid(kvm);
 }
 
-void __hyp_text __kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa)
+void __kvm_tlb_flush_local_vmid(struct kvm_vcpu *vcpu)
 {
-       struct tlb_inv_context cxt;
-
-       dsb(ishst);
-
-       /* Switch to requested VMID */
-       kvm = kern_hyp_va(kvm);
-       __tlb_switch_to_guest(kvm, &cxt);
-
-       /*
-        * We could do so much better if we had the VA as well.
-        * Instead, we invalidate Stage-2 for this IPA, and the
-        * whole of Stage-1. Weep...
-        */
-       ipa >>= 12;
-       __tlbi(ipas2e1is, ipa);
-
-       /*
-        * We have to ensure completion of the invalidation at Stage-2,
-        * since a table walk on another CPU could refill a TLB with a
-        * complete (S1 + S2) walk based on the old Stage-2 mapping if
-        * the Stage-1 invalidation happened first.
-        */
-       dsb(ish);
-       __tlbi(vmalle1is);
-       dsb(ish);
-       isb();
-
-       /*
-        * If the host is running at EL1 and we have a VPIPT I-cache,
-        * then we must perform I-cache maintenance at EL2 in order for
-        * it to have an effect on the guest. Since the guest cannot hit
-        * I-cache lines allocated with a different VMID, we don't need
-        * to worry about junk out of guest reset (we nuke the I-cache on
-        * VMID rollover), but we do need to be careful when remapping
-        * executable pages for the same guest. This can happen when KSM
-        * takes a CoW fault on an executable page, copies the page into
-        * a page that was previously mapped in the guest and then needs
-        * to invalidate the guest view of the I-cache for that page
-        * from EL1. To solve this, we invalidate the entire I-cache when
-        * unmapping a page from a guest if we have a VPIPT I-cache but
-        * the host is running at EL1. As above, we could do better if
-        * we had the VA.
-        *
-        * The moral of this story is: if you have a VPIPT I-cache, then
-        * you should be running with VHE enabled.
-        */
-       if (!has_vhe() && icache_is_vpipt())
-               __flush_icache_all();
-
-       __tlb_switch_to_host(kvm, &cxt);
+       __tlb_flush_local_vmid(vcpu);
 }
 
-void __hyp_text __kvm_tlb_flush_vmid(struct kvm *kvm)
+void __kvm_flush_vm_context(void)
 {
-       struct tlb_inv_context cxt;
-
-       dsb(ishst);
-
-       /* Switch to requested VMID */
-       kvm = kern_hyp_va(kvm);
-       __tlb_switch_to_guest(kvm, &cxt);
-
-       __tlbi(vmalls12e1is);
-       dsb(ish);
-       isb();
-
-       __tlb_switch_to_host(kvm, &cxt);
-}
-
-void __hyp_text __kvm_tlb_flush_local_vmid(struct kvm_vcpu *vcpu)
-{
-       struct kvm *kvm = kern_hyp_va(kern_hyp_va(vcpu)->kvm);
-       struct tlb_inv_context cxt;
-
-       /* Switch to requested VMID */
-       __tlb_switch_to_guest(kvm, &cxt);
-
-       __tlbi(vmalle1);
-       dsb(nsh);
-       isb();
-
-       __tlb_switch_to_host(kvm, &cxt);
-}
-
-void __hyp_text __kvm_flush_vm_context(void)
-{
-       dsb(ishst);
-       __tlbi(alle1is);
-
-       /*
-        * VIPT and PIPT caches are not affected by VMID, so no maintenance
-        * is necessary across a VMID rollover.
-        *
-        * VPIPT caches constrain lookup and maintenance to the active VMID,
-        * so we need to invalidate lines with a stale VMID to avoid an ABA
-        * race after multiple rollovers.
-        *
-        */
-       if (icache_is_vpipt())
-               asm volatile("ic ialluis");
-
-       dsb(ish);
+       __tlb_flush_vm_context();
 }
diff --git a/arch/arm64/kvm/hyp/tlb.h b/arch/arm64/kvm/hyp/tlb.h
new file mode 100644
index 000000000000..f62ed96cb896
--- /dev/null
+++ b/arch/arm64/kvm/hyp/tlb.h
@@ -0,0 +1,129 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2015 - ARM Ltd
+ * Author: Marc Zyngier <marc.zyng...@arm.com>
+ */
+
+#include <linux/irqflags.h>
+
+#include <asm/kvm_hyp.h>
+#include <asm/kvm_mmu.h>
+#include <asm/tlbflush.h>
+
+struct tlb_inv_context {
+       unsigned long   flags;
+       u64             tcr;
+       u64             sctlr;
+};
+
+static void __hyp_text __tlb_switch_to_guest(struct kvm *kvm,
+                                            struct tlb_inv_context *cxt);
+static void __hyp_text __tlb_switch_to_host(struct kvm *kvm,
+                                           struct tlb_inv_context *cxt);
+
+static inline void __hyp_text
+__tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa)
+{
+       struct tlb_inv_context cxt;
+
+       dsb(ishst);
+
+       /* Switch to requested VMID */
+       kvm = kern_hyp_va(kvm);
+       __tlb_switch_to_guest(kvm, &cxt);
+
+       /*
+        * We could do so much better if we had the VA as well.
+        * Instead, we invalidate Stage-2 for this IPA, and the
+        * whole of Stage-1. Weep...
+        */
+       ipa >>= 12;
+       __tlbi(ipas2e1is, ipa);
+
+       /*
+        * We have to ensure completion of the invalidation at Stage-2,
+        * since a table walk on another CPU could refill a TLB with a
+        * complete (S1 + S2) walk based on the old Stage-2 mapping if
+        * the Stage-1 invalidation happened first.
+        */
+       dsb(ish);
+       __tlbi(vmalle1is);
+       dsb(ish);
+       isb();
+
+       /*
+        * If the host is running at EL1 and we have a VPIPT I-cache,
+        * then we must perform I-cache maintenance at EL2 in order for
+        * it to have an effect on the guest. Since the guest cannot hit
+        * I-cache lines allocated with a different VMID, we don't need
+        * to worry about junk out of guest reset (we nuke the I-cache on
+        * VMID rollover), but we do need to be careful when remapping
+        * executable pages for the same guest. This can happen when KSM
+        * takes a CoW fault on an executable page, copies the page into
+        * a page that was previously mapped in the guest and then needs
+        * to invalidate the guest view of the I-cache for that page
+        * from EL1. To solve this, we invalidate the entire I-cache when
+        * unmapping a page from a guest if we have a VPIPT I-cache but
+        * the host is running at EL1. As above, we could do better if
+        * we had the VA.
+        *
+        * The moral of this story is: if you have a VPIPT I-cache, then
+        * you should be running with VHE enabled.
+        */
+       if (!has_vhe() && icache_is_vpipt())
+               __flush_icache_all();
+
+       __tlb_switch_to_host(kvm, &cxt);
+}
+
+static inline void __hyp_text __tlb_flush_vmid(struct kvm *kvm)
+{
+       struct tlb_inv_context cxt;
+
+       dsb(ishst);
+
+       /* Switch to requested VMID */
+       kvm = kern_hyp_va(kvm);
+       __tlb_switch_to_guest(kvm, &cxt);
+
+       __tlbi(vmalls12e1is);
+       dsb(ish);
+       isb();
+
+       __tlb_switch_to_host(kvm, &cxt);
+}
+
+static inline void __hyp_text __tlb_flush_local_vmid(struct kvm_vcpu *vcpu)
+{
+       struct kvm *kvm = kern_hyp_va(kern_hyp_va(vcpu)->kvm);
+       struct tlb_inv_context cxt;
+
+       /* Switch to requested VMID */
+       __tlb_switch_to_guest(kvm, &cxt);
+
+       __tlbi(vmalle1);
+       dsb(nsh);
+       isb();
+
+       __tlb_switch_to_host(kvm, &cxt);
+}
+
+static inline void __hyp_text __tlb_flush_vm_context(void)
+{
+       dsb(ishst);
+       __tlbi(alle1is);
+
+       /*
+        * VIPT and PIPT caches are not affected by VMID, so no maintenance
+        * is necessary across a VMID rollover.
+        *
+        * VPIPT caches constrain lookup and maintenance to the active VMID,
+        * so we need to invalidate lines with a stale VMID to avoid an ABA
+        * race after multiple rollovers.
+        *
+        */
+       if (icache_is_vpipt())
+               asm volatile("ic ialluis");
+
+       dsb(ish);
+}
-- 
2.26.1

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