[PATCH v2 05/18] KVM: x86: Move PIT ioctl helpers to i8254.c
From: Sean Christopherson
Date: Wed Jun 11 2025 - 17:37:41 EST
Move the PIT ioctl helpers to i8254.c, i.e. to the file that implements
PIT emulation. Eliminating PIT code in x86.c will allow adding a Kconfig
to control support for in-kernel I/O APIC, PIC, and PIT emulation with
minimal #ifdefs.
Opportunistically make kvm_pit_set_reinject() and kvm_pit_load_count()
local to i8254.c as they were only publicly visible to make them available
to the ioctl helpers.
No functional change intended.
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
arch/x86/kvm/i8254.c | 79 ++++++++++++++++++++++++++++++++++++++++++--
arch/x86/kvm/i8254.h | 12 ++++---
arch/x86/kvm/x86.c | 74 -----------------------------------------
3 files changed, 84 insertions(+), 81 deletions(-)
diff --git a/arch/x86/kvm/i8254.c b/arch/x86/kvm/i8254.c
index 739aa6c0d0c3..59f956f35f4c 100644
--- a/arch/x86/kvm/i8254.c
+++ b/arch/x86/kvm/i8254.c
@@ -288,7 +288,7 @@ static inline void kvm_pit_reset_reinject(struct kvm_pit *pit)
atomic_set(&pit->pit_state.irq_ack, 1);
}
-void kvm_pit_set_reinject(struct kvm_pit *pit, bool reinject)
+static void kvm_pit_set_reinject(struct kvm_pit *pit, bool reinject)
{
struct kvm_kpit_state *ps = &pit->pit_state;
struct kvm *kvm = pit->kvm;
@@ -400,8 +400,8 @@ static void pit_load_count(struct kvm_pit *pit, int channel, u32 val)
}
}
-void kvm_pit_load_count(struct kvm_pit *pit, int channel, u32 val,
- int hpet_legacy_start)
+static void kvm_pit_load_count(struct kvm_pit *pit, int channel, u32 val,
+ int hpet_legacy_start)
{
u8 saved_mode;
@@ -649,6 +649,79 @@ static void pit_mask_notifer(struct kvm_irq_mask_notifier *kimn, bool mask)
kvm_pit_reset_reinject(pit);
}
+int kvm_vm_ioctl_get_pit(struct kvm *kvm, struct kvm_pit_state *ps)
+{
+ struct kvm_kpit_state *kps = &kvm->arch.vpit->pit_state;
+
+ BUILD_BUG_ON(sizeof(*ps) != sizeof(kps->channels));
+
+ mutex_lock(&kps->lock);
+ memcpy(ps, &kps->channels, sizeof(*ps));
+ mutex_unlock(&kps->lock);
+ return 0;
+}
+
+int kvm_vm_ioctl_set_pit(struct kvm *kvm, struct kvm_pit_state *ps)
+{
+ int i;
+ struct kvm_pit *pit = kvm->arch.vpit;
+
+ mutex_lock(&pit->pit_state.lock);
+ memcpy(&pit->pit_state.channels, ps, sizeof(*ps));
+ for (i = 0; i < 3; i++)
+ kvm_pit_load_count(pit, i, ps->channels[i].count, 0);
+ mutex_unlock(&pit->pit_state.lock);
+ return 0;
+}
+
+int kvm_vm_ioctl_get_pit2(struct kvm *kvm, struct kvm_pit_state2 *ps)
+{
+ mutex_lock(&kvm->arch.vpit->pit_state.lock);
+ memcpy(ps->channels, &kvm->arch.vpit->pit_state.channels,
+ sizeof(ps->channels));
+ ps->flags = kvm->arch.vpit->pit_state.flags;
+ mutex_unlock(&kvm->arch.vpit->pit_state.lock);
+ memset(&ps->reserved, 0, sizeof(ps->reserved));
+ return 0;
+}
+
+int kvm_vm_ioctl_set_pit2(struct kvm *kvm, struct kvm_pit_state2 *ps)
+{
+ int start = 0;
+ int i;
+ u32 prev_legacy, cur_legacy;
+ struct kvm_pit *pit = kvm->arch.vpit;
+
+ mutex_lock(&pit->pit_state.lock);
+ prev_legacy = pit->pit_state.flags & KVM_PIT_FLAGS_HPET_LEGACY;
+ cur_legacy = ps->flags & KVM_PIT_FLAGS_HPET_LEGACY;
+ if (!prev_legacy && cur_legacy)
+ start = 1;
+ memcpy(&pit->pit_state.channels, &ps->channels,
+ sizeof(pit->pit_state.channels));
+ pit->pit_state.flags = ps->flags;
+ for (i = 0; i < 3; i++)
+ kvm_pit_load_count(pit, i, pit->pit_state.channels[i].count,
+ start && i == 0);
+ mutex_unlock(&pit->pit_state.lock);
+ return 0;
+}
+
+int kvm_vm_ioctl_reinject(struct kvm *kvm, struct kvm_reinject_control *control)
+{
+ struct kvm_pit *pit = kvm->arch.vpit;
+
+ /* pit->pit_state.lock was overloaded to prevent userspace from getting
+ * an inconsistent state after running multiple KVM_REINJECT_CONTROL
+ * ioctls in parallel. Use a separate lock if that ioctl isn't rare.
+ */
+ mutex_lock(&pit->pit_state.lock);
+ kvm_pit_set_reinject(pit, control->pit_reinject);
+ mutex_unlock(&pit->pit_state.lock);
+
+ return 0;
+}
+
static const struct kvm_io_device_ops pit_dev_ops = {
.read = pit_ioport_read,
.write = pit_ioport_write,
diff --git a/arch/x86/kvm/i8254.h b/arch/x86/kvm/i8254.h
index a768212ba821..338095829ec8 100644
--- a/arch/x86/kvm/i8254.h
+++ b/arch/x86/kvm/i8254.h
@@ -6,6 +6,8 @@
#include <kvm/iodev.h>
+#include <uapi/asm/kvm.h>
+
struct kvm_kpit_channel_state {
u32 count; /* can be 65536 */
u16 latched_count;
@@ -55,11 +57,13 @@ struct kvm_pit {
#define KVM_MAX_PIT_INTR_INTERVAL HZ / 100
#define KVM_PIT_CHANNEL_MASK 0x3
+int kvm_vm_ioctl_get_pit(struct kvm *kvm, struct kvm_pit_state *ps);
+int kvm_vm_ioctl_set_pit(struct kvm *kvm, struct kvm_pit_state *ps);
+int kvm_vm_ioctl_get_pit2(struct kvm *kvm, struct kvm_pit_state2 *ps);
+int kvm_vm_ioctl_set_pit2(struct kvm *kvm, struct kvm_pit_state2 *ps);
+int kvm_vm_ioctl_reinject(struct kvm *kvm, struct kvm_reinject_control *control);
+
struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags);
void kvm_free_pit(struct kvm *kvm);
-void kvm_pit_load_count(struct kvm_pit *pit, int channel, u32 val,
- int hpet_legacy_start);
-void kvm_pit_set_reinject(struct kvm_pit *pit, bool reinject);
-
#endif
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index dd34a2ec854c..50e9fa57b859 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6450,80 +6450,6 @@ static int kvm_vm_ioctl_set_irqchip(struct kvm *kvm, struct kvm_irqchip *chip)
return r;
}
-static int kvm_vm_ioctl_get_pit(struct kvm *kvm, struct kvm_pit_state *ps)
-{
- struct kvm_kpit_state *kps = &kvm->arch.vpit->pit_state;
-
- BUILD_BUG_ON(sizeof(*ps) != sizeof(kps->channels));
-
- mutex_lock(&kps->lock);
- memcpy(ps, &kps->channels, sizeof(*ps));
- mutex_unlock(&kps->lock);
- return 0;
-}
-
-static int kvm_vm_ioctl_set_pit(struct kvm *kvm, struct kvm_pit_state *ps)
-{
- int i;
- struct kvm_pit *pit = kvm->arch.vpit;
-
- mutex_lock(&pit->pit_state.lock);
- memcpy(&pit->pit_state.channels, ps, sizeof(*ps));
- for (i = 0; i < 3; i++)
- kvm_pit_load_count(pit, i, ps->channels[i].count, 0);
- mutex_unlock(&pit->pit_state.lock);
- return 0;
-}
-
-static int kvm_vm_ioctl_get_pit2(struct kvm *kvm, struct kvm_pit_state2 *ps)
-{
- mutex_lock(&kvm->arch.vpit->pit_state.lock);
- memcpy(ps->channels, &kvm->arch.vpit->pit_state.channels,
- sizeof(ps->channels));
- ps->flags = kvm->arch.vpit->pit_state.flags;
- mutex_unlock(&kvm->arch.vpit->pit_state.lock);
- memset(&ps->reserved, 0, sizeof(ps->reserved));
- return 0;
-}
-
-static int kvm_vm_ioctl_set_pit2(struct kvm *kvm, struct kvm_pit_state2 *ps)
-{
- int start = 0;
- int i;
- u32 prev_legacy, cur_legacy;
- struct kvm_pit *pit = kvm->arch.vpit;
-
- mutex_lock(&pit->pit_state.lock);
- prev_legacy = pit->pit_state.flags & KVM_PIT_FLAGS_HPET_LEGACY;
- cur_legacy = ps->flags & KVM_PIT_FLAGS_HPET_LEGACY;
- if (!prev_legacy && cur_legacy)
- start = 1;
- memcpy(&pit->pit_state.channels, &ps->channels,
- sizeof(pit->pit_state.channels));
- pit->pit_state.flags = ps->flags;
- for (i = 0; i < 3; i++)
- kvm_pit_load_count(pit, i, pit->pit_state.channels[i].count,
- start && i == 0);
- mutex_unlock(&pit->pit_state.lock);
- return 0;
-}
-
-static int kvm_vm_ioctl_reinject(struct kvm *kvm,
- struct kvm_reinject_control *control)
-{
- struct kvm_pit *pit = kvm->arch.vpit;
-
- /* pit->pit_state.lock was overloaded to prevent userspace from getting
- * an inconsistent state after running multiple KVM_REINJECT_CONTROL
- * ioctls in parallel. Use a separate lock if that ioctl isn't rare.
- */
- mutex_lock(&pit->pit_state.lock);
- kvm_pit_set_reinject(pit, control->pit_reinject);
- mutex_unlock(&pit->pit_state.lock);
-
- return 0;
-}
-
void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
{
--
2.50.0.rc1.591.g9c95f17f64-goog