vfio: Refactor ioport trap handler

With the planned retirement of the special ioport emulation code, we
need to provide an emulation function compatible with the MMIO prototype.

Adjust the I/O port trap handler to use that new function, and provide
shims to implement the old ioport interface, for now.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com>
Link: https://lore.kernel.org/r/20210315153350.19988-16-andre.przywara@arm.com
Signed-off-by: Will Deacon <will@kernel.org>

1 files changed, 36 insertions, 15 deletions

diff --git a/vfio/core.c b/vfio/core.c
index 0b45e78b..ddd3c2c7 100644
--- a/vfio/core.c
+++ b/vfio/core.c
@@ -81,15 +81,12 @@ out_free_buf:
 	return ret;
 }
 
-static bool vfio_ioport_in(struct ioport *ioport, struct kvm_cpu *vcpu,
-			   u16 port, void *data, int len)
+static bool _vfio_ioport_in(struct vfio_region *region, u32 offset,
+			    void *data, int len)
 {
-	u32 val;
-	ssize_t nr;
-	struct vfio_region *region = ioport->priv;
 	struct vfio_device *vdev = region->vdev;
-
-	u32 offset = port - region->port_base;
+	ssize_t nr;
+	u32 val;
 
 	if (!(region->info.flags & VFIO_REGION_INFO_FLAG_READ))
 		return false;
@@ -97,7 +94,7 @@ static bool vfio_ioport_in(struct ioport *ioport, struct kvm_cpu *vcpu,
 	nr = pread(vdev->fd, &val, len, region->info.offset + offset);
 	if (nr != len) {
 		vfio_dev_err(vdev, "could not read %d bytes from I/O port 0x%x\n",
-			     len, port);
+			     len, offset + region->port_base);
 		return false;
 	}
 
@@ -118,15 +115,13 @@ static bool vfio_ioport_in(struct ioport *ioport, struct kvm_cpu *vcpu,
 	return true;
 }
 
-static bool vfio_ioport_out(struct ioport *ioport, struct kvm_cpu *vcpu,
-			    u16 port, void *data, int len)
+static bool _vfio_ioport_out(struct vfio_region *region, u32 offset,
+			     void *data, int len)
 {
-	u32 val;
-	ssize_t nr;
-	struct vfio_region *region = ioport->priv;
 	struct vfio_device *vdev = region->vdev;
+	ssize_t nr;
+	u32 val;
 
-	u32 offset = port - region->port_base;
 
 	if (!(region->info.flags & VFIO_REGION_INFO_FLAG_WRITE))
 		return false;
@@ -148,11 +143,37 @@ static bool vfio_ioport_out(struct ioport *ioport, struct kvm_cpu *vcpu,
 	nr = pwrite(vdev->fd, &val, len, region->info.offset + offset);
 	if (nr != len)
 		vfio_dev_err(vdev, "could not write %d bytes to I/O port 0x%x",
-			     len, port);
+			     len, offset + region->port_base);
 
 	return nr == len;
 }
 
+static void vfio_ioport_mmio(struct kvm_cpu *vcpu, u64 addr, u8 *data, u32 len,
+			     u8 is_write, void *ptr)
+{
+	struct vfio_region *region = ptr;
+	u32 offset = addr - region->port_base;
+
+	if (is_write)
+		_vfio_ioport_out(region, offset, data, len);
+	else
+		_vfio_ioport_in(region, offset, data, len);
+}
+
+static bool vfio_ioport_out(struct ioport *ioport, struct kvm_cpu *vcpu,
+			    u16 port, void *data, int len)
+{
+	vfio_ioport_mmio(vcpu, port, data, len, true, ioport->priv);
+	return true;
+}
+
+static bool vfio_ioport_in(struct ioport *ioport, struct kvm_cpu *vcpu,
+			   u16 port, void *data, int len)
+{
+	vfio_ioport_mmio(vcpu, port, data, len, false, ioport->priv);
+	return true;
+}
+
 static struct ioport_operations vfio_ioport_ops = {
 	.io_in	= vfio_ioport_in,
 	.io_out	= vfio_ioport_out,