From eb3f05171c2e84f0114403df0fea942479fdaa3e Mon Sep 17 00:00:00 2001
From: Pei Zhang <pei.zhang@intel.com>
Date: Mon, 11 Dec 2017 17:15:02 +0800
Subject: [PATCH] drm/i915/gvt: refine function emulate_mmio_read/write
Git-commit: eb3f05171c2e84f0114403df0fea942479fdaa3e
Patch-mainline: v4.16-rc1
References: FATE#322643 bsc#1055900

These 2 functions are coded by multiple person in multiple patches. The
'return' and 'goto err' are mix-used in same place, which cause the
function looks disorder. Unify to use only 'goto' so that the gvt lock
is acquired in one place and released in one place.

Signed-off-by: Pei Zhang <pei.zhang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/gpu/drm/i915/gvt/mmio.c |   36 +++++++++++++++---------------------
 1 file changed, 15 insertions(+), 21 deletions(-)

--- a/drivers/gpu/drm/i915/gvt/mmio.c
+++ b/drivers/gpu/drm/i915/gvt/mmio.c
@@ -157,7 +157,6 @@ int intel_vgpu_emulate_mmio_read(struct
 	unsigned int offset = 0;
 	int ret = -EINVAL;
 
-
 	if (vgpu->failsafe) {
 		failsafe_emulate_mmio_rw(vgpu, pa, p_data, bytes, true);
 		return 0;
@@ -166,8 +165,7 @@ int intel_vgpu_emulate_mmio_read(struct
 
 	if (vgpu_gpa_is_aperture(vgpu, pa)) {
 		ret = vgpu_aperture_rw(vgpu, pa, p_data, bytes, true);
-		mutex_unlock(&gvt->lock);
-		return ret;
+		goto out;
 	}
 
 	if (atomic_read(&vgpu->gtt.n_tracked_guest_page)) {
@@ -183,8 +181,7 @@ int intel_vgpu_emulate_mmio_read(struct
 					ret, t->gfn, pa, *(u32 *)p_data,
 					bytes);
 			}
-			mutex_unlock(&gvt->lock);
-			return ret;
+			goto out;
 		}
 	}
 
@@ -205,14 +202,12 @@ int intel_vgpu_emulate_mmio_read(struct
 				p_data, bytes);
 		if (ret)
 			goto err;
-		mutex_unlock(&gvt->lock);
-		return ret;
+		goto out;
 	}
 
 	if (WARN_ON_ONCE(!reg_is_mmio(gvt, offset))) {
 		ret = intel_gvt_hypervisor_read_gpa(vgpu, pa, p_data, bytes);
-		mutex_unlock(&gvt->lock);
-		return ret;
+		goto out;
 	}
 
 	if (WARN_ON(!reg_is_mmio(gvt, offset + bytes - 1)))
@@ -228,11 +223,13 @@ int intel_vgpu_emulate_mmio_read(struct
 		goto err;
 
 	intel_gvt_mmio_set_accessed(gvt, offset);
-	mutex_unlock(&gvt->lock);
-	return 0;
+	ret = 0;
+	goto out;
+
 err:
 	gvt_vgpu_err("fail to emulate MMIO read %08x len %d\n",
 			offset, bytes);
+out:
 	mutex_unlock(&gvt->lock);
 	return ret;
 }
@@ -263,8 +260,7 @@ int intel_vgpu_emulate_mmio_write(struct
 
 	if (vgpu_gpa_is_aperture(vgpu, pa)) {
 		ret = vgpu_aperture_rw(vgpu, pa, p_data, bytes, false);
-		mutex_unlock(&gvt->lock);
-		return ret;
+		goto out;
 	}
 
 	if (atomic_read(&vgpu->gtt.n_tracked_guest_page)) {
@@ -280,8 +276,7 @@ int intel_vgpu_emulate_mmio_write(struct
 					ret, t->gfn, pa,
 					*(u32 *)p_data, bytes);
 			}
-			mutex_unlock(&gvt->lock);
-			return ret;
+			goto out;
 		}
 	}
 
@@ -302,14 +297,12 @@ int intel_vgpu_emulate_mmio_write(struct
 				p_data, bytes);
 		if (ret)
 			goto err;
-		mutex_unlock(&gvt->lock);
-		return ret;
+		goto out;
 	}
 
 	if (WARN_ON_ONCE(!reg_is_mmio(gvt, offset))) {
 		ret = intel_gvt_hypervisor_write_gpa(vgpu, pa, p_data, bytes);
-		mutex_unlock(&gvt->lock);
-		return ret;
+		goto out;
 	}
 
 	ret = intel_vgpu_mmio_reg_rw(vgpu, offset, p_data, bytes, false);
@@ -317,11 +310,12 @@ int intel_vgpu_emulate_mmio_write(struct
 		goto err;
 
 	intel_gvt_mmio_set_accessed(gvt, offset);
-	mutex_unlock(&gvt->lock);
-	return 0;
+	ret = 0;
+	goto out;
 err:
 	gvt_vgpu_err("fail to emulate MMIO write %08x len %d\n", offset,
 		     bytes);
+out:
 	mutex_unlock(&gvt->lock);
 	return ret;
 }