[RFC PATCH 33/37] KVM: Move kvm_arch_flush_remote_tlbs_memslot() to common code

David Matlack
2022-12-08T20:28:32Z

Move kvm_arch_flush_remote_tlbs_memslot() to common code and drop
"arch_" from the name. kvm_arch_flush_remote_tlbs_memslot() is just a
range-based TLB invalidation where the range is defined by the memslot.
Now that kvm_flush_remote_tlbs_range() can be called from common code we
can just use that and drop a bunch of duplicate code from the arch
directories.

Note this adds a lockdep assertion for slot_lock being held when calling
kvm_flush_remote_tlbs_memslot(), which was previously only asserted on
x86.

Signed-off-by: David Matlack <dmatlack@google.com>
---
arch/arm64/kvm/arm.c | 6 ------
arch/mips/kvm/mips.c | 10 ++--------
arch/riscv/kvm/mmu.c | 6 ------
arch/x86/kvm/mmu/mmu.c | 16 +---------------
arch/x86/kvm/x86.c | 2 +-
include/linux/kvm_host.h | 7 +++----
virt/kvm/kvm_main.c | 17 +++++++++++++++--
7 files changed, 22 insertions(+), 42 deletions(-)

diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index 0e0d4c4f79a2..4f1549c1d2d2 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -1430,12 +1430,6 @@ void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)

}

-void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm,
- const struct kvm_memory_slot *memslot)
-{
- kvm_flush_remote_tlbs(kvm);
-}
-
static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm,
struct kvm_arm_device_addr *dev_addr)
{
diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c
index a25e0b73ee70..ecd8a051fd6b 100644
--- a/arch/mips/kvm/mips.c
+++ b/arch/mips/kvm/mips.c
@@ -209,7 +209,7 @@ void kvm_arch_flush_shadow_memslot(struct kvm *kvm,
/* Flush slot from GPA */
kvm_mips_flush_gpa_pt(kvm, slot->base_gfn,
slot->base_gfn + slot->npages - 1);
- kvm_arch_flush_remote_tlbs_memslot(kvm, slot);
+ kvm_flush_remote_tlbs_memslot(kvm, slot);
spin_unlock(&kvm->mmu_lock);
}

@@ -245,7 +245,7 @@ void kvm_arch_commit_memory_region(struct kvm *kvm,
needs_flush = kvm_mips_mkclean_gpa_pt(kvm, new->base_gfn,
new->base_gfn + new->npages - 1);
if (needs_flush)
- kvm_arch_flush_remote_tlbs_memslot(kvm, new);
+ kvm_flush_remote_tlbs_memslot(kvm, new);
spin_unlock(&kvm->mmu_lock);
}
}
@@ -997,12 +997,6 @@ int kvm_arch_flush_remote_tlb(struct kvm *kvm)
return 1;
}

-void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm,
- const struct kvm_memory_slot *memslot)
-{
- kvm_flush_remote_tlbs(kvm);
-}
-
long kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
{
long r;
diff --git a/arch/riscv/kvm/mmu.c b/arch/riscv/kvm/mmu.c
index a8281a65cb3d..98bf3719a396 100644
--- a/arch/riscv/kvm/mmu.c
+++ b/arch/riscv/kvm/mmu.c
@@ -406,12 +406,6 @@ void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
{
}

-void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm,
- const struct kvm_memory_slot *memslot)
-{
- kvm_flush_remote_tlbs(kvm);
-}
-
void kvm_arch_free_memslot(struct kvm *kvm, struct kvm_memory_slot *free)
{
}
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 19963ed83484..f2602ee1771f 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -6524,7 +6524,7 @@ static void kvm_rmap_zap_collapsible_sptes(struct kvm *kvm,
*/
if (slot_handle_level(kvm, slot, kvm_mmu_zap_collapsible_spte,
PG_LEVEL_4K, KVM_MAX_HUGEPAGE_LEVEL - 1, true))
- kvm_arch_flush_remote_tlbs_memslot(kvm, slot);
+ kvm_flush_remote_tlbs_memslot(kvm, slot);
}

void kvm_mmu_zap_collapsible_sptes(struct kvm *kvm,
@@ -6543,20 +6543,6 @@ void kvm_mmu_zap_collapsible_sptes(struct kvm *kvm,
}
}

-void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm,
- const struct kvm_memory_slot *memslot)
-{
- /*
- * All current use cases for flushing the TLBs for a specific memslot
- * related to dirty logging, and many do the TLB flush out of mmu_lock.
- * The interaction between the various operations on memslot must be
- * serialized by slots_locks to ensure the TLB flush from one operation
- * is observed by any other operation on the same memslot.
- */
- lockdep_assert_held(&kvm->slots_lock);
- kvm_flush_remote_tlbs_range(kvm, memslot->base_gfn, memslot->npages);
-}
-
void kvm_mmu_slot_leaf_clear_dirty(struct kvm *kvm,
const struct kvm_memory_slot *memslot)
{
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 517c8ed33542..95ff95da55d5 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -12574,7 +12574,7 @@ static void kvm_mmu_slot_apply_flags(struct kvm *kvm,
* See is_writable_pte() for more details (the case involving
* access-tracked SPTEs is particularly relevant).
*/
- kvm_arch_flush_remote_tlbs_memslot(kvm, new);
+ kvm_flush_remote_tlbs_memslot(kvm, new);
}
}

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index d9a7f559d2c5..46ed0ef4fb79 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -1366,6 +1366,8 @@ void kvm_vcpu_on_spin(struct kvm_vcpu *vcpu, bool usermode_vcpu_not_eligible);

void kvm_flush_remote_tlbs(struct kvm *kvm);
void kvm_flush_remote_tlbs_range(struct kvm *kvm, gfn_t start_gfn, u64 pages);
+void kvm_flush_remote_tlbs_memslot(struct kvm *kvm,
+ const struct kvm_memory_slot *memslot);

#ifdef KVM_ARCH_NR_OBJS_PER_MEMORY_CACHE
int kvm_mmu_topup_memory_cache(struct kvm_mmu_memory_cache *mc, int min);
@@ -1394,10 +1396,7 @@ void kvm_arch_mmu_enable_log_dirty_pt_masked(struct kvm *kvm,
unsigned long mask);
void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot);

-#ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
-void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm,
- const struct kvm_memory_slot *memslot);
-#else /* !CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT */
+#ifndef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log);
int kvm_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log,
int *is_dirty, struct kvm_memory_slot **memslot);
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 662ca280c0cf..39c2efd15504 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -388,6 +388,19 @@ void __weak kvm_flush_remote_tlbs_range(struct kvm *kvm, gfn_t start_gfn, u64 pa
kvm_flush_remote_tlbs(kvm);
}

+void kvm_flush_remote_tlbs_memslot(struct kvm *kvm, const struct kvm_memory_slot *memslot)
+{
+ /*
+ * All current use cases for flushing the TLBs for a specific memslot
+ * related to dirty logging, and many do the TLB flush out of mmu_lock.
+ * The interaction between the various operations on memslot must be
+ * serialized by slots_locks to ensure the TLB flush from one operation
+ * is observed by any other operation on the same memslot.
+ */
+ lockdep_assert_held(&kvm->slots_lock);
+ kvm_flush_remote_tlbs_range(kvm, memslot->base_gfn, memslot->npages);
+}
+
static void kvm_flush_shadow_all(struct kvm *kvm)
{
kvm_arch_flush_shadow_all(kvm);
@@ -2197,7 +2210,7 @@ static int kvm_get_dirty_log_protect(struct kvm *kvm, struct kvm_dirty_log *log)
}

if (flush)
- kvm_arch_flush_remote_tlbs_memslot(kvm, memslot);
+ kvm_flush_remote_tlbs_memslot(kvm, memslot);

if (copy_to_user(log->dirty_bitmap, dirty_bitmap_buffer, n))
return -EFAULT;
@@ -2314,7 +2327,7 @@ static int kvm_clear_dirty_log_protect(struct kvm *kvm,
KVM_MMU_UNLOCK(kvm);

if (flush)
- kvm_arch_flush_remote_tlbs_memslot(kvm, memslot);
+ kvm_flush_remote_tlbs_memslot(kvm, memslot);

return 0;
}
--
2.39.0.rc1.256.g54fd8350bd-goog