KVM: remove in_range from io devices
This changes bus accesses to use high-level kvm_io_bus_read/kvm_io_bus_write
functions. in_range now becomes unused so it is removed from device ops in
favor of read/write callbacks performing range checks internally.
This allows aliasing (mostly for in-kernel virtio), as well as better error
handling by making it possible to pass errors up to userspace.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/kvm/i8254.c b/arch/x86/kvm/i8254.c
index 4082cdd..8c3ac30 100644
--- a/arch/x86/kvm/i8254.c
+++ b/arch/x86/kvm/i8254.c
@@ -358,8 +358,14 @@
return container_of(dev, struct kvm_pit, speaker_dev);
}
-static void pit_ioport_write(struct kvm_io_device *this,
- gpa_t addr, int len, const void *data)
+static inline int pit_in_range(gpa_t addr)
+{
+ return ((addr >= KVM_PIT_BASE_ADDRESS) &&
+ (addr < KVM_PIT_BASE_ADDRESS + KVM_PIT_MEM_LENGTH));
+}
+
+static int pit_ioport_write(struct kvm_io_device *this,
+ gpa_t addr, int len, const void *data)
{
struct kvm_pit *pit = dev_to_pit(this);
struct kvm_kpit_state *pit_state = &pit->pit_state;
@@ -367,6 +373,8 @@
int channel, access;
struct kvm_kpit_channel_state *s;
u32 val = *(u32 *) data;
+ if (!pit_in_range(addr))
+ return -EOPNOTSUPP;
val &= 0xff;
addr &= KVM_PIT_CHANNEL_MASK;
@@ -429,16 +437,19 @@
}
mutex_unlock(&pit_state->lock);
+ return 0;
}
-static void pit_ioport_read(struct kvm_io_device *this,
- gpa_t addr, int len, void *data)
+static int pit_ioport_read(struct kvm_io_device *this,
+ gpa_t addr, int len, void *data)
{
struct kvm_pit *pit = dev_to_pit(this);
struct kvm_kpit_state *pit_state = &pit->pit_state;
struct kvm *kvm = pit->kvm;
int ret, count;
struct kvm_kpit_channel_state *s;
+ if (!pit_in_range(addr))
+ return -EOPNOTSUPP;
addr &= KVM_PIT_CHANNEL_MASK;
s = &pit_state->channels[addr];
@@ -493,37 +504,36 @@
memcpy(data, (char *)&ret, len);
mutex_unlock(&pit_state->lock);
+ return 0;
}
-static int pit_in_range(struct kvm_io_device *this, gpa_t addr,
- int len, int is_write)
-{
- return ((addr >= KVM_PIT_BASE_ADDRESS) &&
- (addr < KVM_PIT_BASE_ADDRESS + KVM_PIT_MEM_LENGTH));
-}
-
-static void speaker_ioport_write(struct kvm_io_device *this,
- gpa_t addr, int len, const void *data)
+static int speaker_ioport_write(struct kvm_io_device *this,
+ gpa_t addr, int len, const void *data)
{
struct kvm_pit *pit = speaker_to_pit(this);
struct kvm_kpit_state *pit_state = &pit->pit_state;
struct kvm *kvm = pit->kvm;
u32 val = *(u32 *) data;
+ if (addr != KVM_SPEAKER_BASE_ADDRESS)
+ return -EOPNOTSUPP;
mutex_lock(&pit_state->lock);
pit_state->speaker_data_on = (val >> 1) & 1;
pit_set_gate(kvm, 2, val & 1);
mutex_unlock(&pit_state->lock);
+ return 0;
}
-static void speaker_ioport_read(struct kvm_io_device *this,
- gpa_t addr, int len, void *data)
+static int speaker_ioport_read(struct kvm_io_device *this,
+ gpa_t addr, int len, void *data)
{
struct kvm_pit *pit = speaker_to_pit(this);
struct kvm_kpit_state *pit_state = &pit->pit_state;
struct kvm *kvm = pit->kvm;
unsigned int refresh_clock;
int ret;
+ if (addr != KVM_SPEAKER_BASE_ADDRESS)
+ return -EOPNOTSUPP;
/* Refresh clock toggles at about 15us. We approximate as 2^14ns. */
refresh_clock = ((unsigned int)ktime_to_ns(ktime_get()) >> 14) & 1;
@@ -535,12 +545,7 @@
len = sizeof(ret);
memcpy(data, (char *)&ret, len);
mutex_unlock(&pit_state->lock);
-}
-
-static int speaker_in_range(struct kvm_io_device *this, gpa_t addr,
- int len, int is_write)
-{
- return (addr == KVM_SPEAKER_BASE_ADDRESS);
+ return 0;
}
void kvm_pit_reset(struct kvm_pit *pit)
@@ -574,13 +579,11 @@
static const struct kvm_io_device_ops pit_dev_ops = {
.read = pit_ioport_read,
.write = pit_ioport_write,
- .in_range = pit_in_range,
};
static const struct kvm_io_device_ops speaker_dev_ops = {
.read = speaker_ioport_read,
.write = speaker_ioport_write,
- .in_range = speaker_in_range,
};
/* Caller must have writers lock on slots_lock */