drm/i915/gvt: devirtualize ->inject_msi

Just open code the MSI injection in a single place instead of going
through the method table.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20220411141403.86980-18-hch@lst.de
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>

1 files changed, 39 insertions, 1 deletions

diff --git a/drivers/gpu/drm/i915/gvt/interrupt.c b/drivers/gpu/drm/i915/gvt/interrupt.c
index 228f623d466d..a6b2021b665f 100644
--- a/drivers/gpu/drm/i915/gvt/interrupt.c
+++ b/drivers/gpu/drm/i915/gvt/interrupt.c
@@ -29,6 +29,8 @@
  *
  */
 
+#include <linux/eventfd.h>
+
 #include "i915_drv.h"
 #include "i915_reg.h"
 #include "gvt.h"
@@ -397,9 +399,45 @@ static void init_irq_map(struct intel_gvt_irq *irq)
 }
 
 /* =======================vEvent injection===================== */
+
+#define MSI_CAP_CONTROL(offset) (offset + 2)
+#define MSI_CAP_ADDRESS(offset) (offset + 4)
+#define MSI_CAP_DATA(offset) (offset + 8)
+#define MSI_CAP_EN 0x1
+
 static int inject_virtual_interrupt(struct intel_vgpu *vgpu)
 {
-	return intel_gvt_hypervisor_inject_msi(vgpu);
+	unsigned long offset = vgpu->gvt->device_info.msi_cap_offset;
+	u16 control, data;
+	u32 addr;
+
+	control = *(u16 *)(vgpu_cfg_space(vgpu) + MSI_CAP_CONTROL(offset));
+	addr = *(u32 *)(vgpu_cfg_space(vgpu) + MSI_CAP_ADDRESS(offset));
+	data = *(u16 *)(vgpu_cfg_space(vgpu) + MSI_CAP_DATA(offset));
+
+	/* Do not generate MSI if MSIEN is disabled */
+	if (!(control & MSI_CAP_EN))
+		return 0;
+
+	if (WARN(control & GENMASK(15, 1), "only support one MSI format\n"))
+		return -EINVAL;
+
+	trace_inject_msi(vgpu->id, addr, data);
+
+	/*
+	 * When guest is powered off, msi_trigger is set to NULL, but vgpu's
+	 * config and mmio register isn't restored to default during guest
+	 * poweroff. If this vgpu is still used in next vm, this vgpu's pipe
+	 * may be enabled, then once this vgpu is active, it will get inject
+	 * vblank interrupt request. But msi_trigger is null until msi is
+	 * enabled by guest. so if msi_trigger is null, success is still
+	 * returned and don't inject interrupt into guest.
+	 */
+	if (!vgpu->attached)
+		return -ESRCH;
+	if (vgpu->msi_trigger && eventfd_signal(vgpu->msi_trigger, 1) != 1)
+		return -EFAULT;
+	return 0;
 }
 
 static void propagate_event(struct intel_gvt_irq *irq,