msm: mdss: Fix scalar LUT handling

Add lock to serialize access between userspace
and kernel. Fix error handling for LUT allocation.

Change-Id: Ie86a8eb3e2a11852ae16d87ebc851afb6566732f
Signed-off-by: Animesh Kishore <animeshk@codeaurora.org>

4 files changed, 45 insertions, 17 deletions

diff --git a/drivers/video/fbdev/msm/mdss.h b/drivers/video/fbdev/msm/mdss.h
index 5548f0f09f8a..1ccb27113c11 100644
--- a/drivers/video/fbdev/msm/mdss.h
+++ b/drivers/video/fbdev/msm/mdss.h
@@ -1,4 +1,4 @@
-/* Copyright (c) 2012-2017, The Linux Foundation. All rights reserved.
+/* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 and
@@ -255,6 +255,13 @@ struct mdss_scaler_block {
 	u32 *dest_scaler_off;
 	u32 *dest_scaler_lut_off;
 	struct mdss_mdp_qseed3_lut_tbl lut_tbl;
+
+	/*
+	 * Lock is mainly to serialize access to LUT.
+	 * LUT values come asynchronously from userspace
+	 * via ioctl.
+	 */
+	struct mutex scaler_lock;
 };
 
 struct mdss_data_type;
diff --git a/drivers/video/fbdev/msm/mdss_mdp.c b/drivers/video/fbdev/msm/mdss_mdp.c
index 410d36a3ac31..a77e5c4435bb 100644
--- a/drivers/video/fbdev/msm/mdss_mdp.c
+++ b/drivers/video/fbdev/msm/mdss_mdp.c
@@ -1,7 +1,7 @@
 /*
  * MDSS MDP Interface (used by framebuffer core)
  *
- * Copyright (c) 2007-2017, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2007-2018, The Linux Foundation. All rights reserved.
  * Copyright (C) 2007 Google Incorporated
  *
  * This software is licensed under the terms of the GNU General Public
@@ -2436,6 +2436,8 @@ static u32 mdss_mdp_scaler_init(struct mdss_data_type *mdata,
 		ret = mdss_mdp_ds_addr_setup(mdata);
 	}
 
+	mutex_init(&mdata->scaler_off->scaler_lock);
+
 	return ret;
 }
 
diff --git a/drivers/video/fbdev/msm/mdss_mdp_overlay.c b/drivers/video/fbdev/msm/mdss_mdp_overlay.c
index 11c159630747..791c73baa9e7 100644
--- a/drivers/video/fbdev/msm/mdss_mdp_overlay.c
+++ b/drivers/video/fbdev/msm/mdss_mdp_overlay.c
@@ -1,4 +1,4 @@
-/* Copyright (c) 2012-2017, The Linux Foundation. All rights reserved.
+/* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 and
@@ -6631,14 +6631,18 @@ static int mdss_mdp_scaler_lut_init(struct mdss_data_type *mdata,
 	if (!mdata->scaler_off)
 		return -EFAULT;
 
+	mutex_lock(&mdata->scaler_off->scaler_lock);
+
 	qseed3_lut_tbl = &mdata->scaler_off->lut_tbl;
 	if ((lut_tbl->dir_lut_size !=
 		DIR_LUT_IDX * DIR_LUT_COEFFS * sizeof(uint32_t)) ||
 		(lut_tbl->cir_lut_size !=
 		 CIR_LUT_IDX * CIR_LUT_COEFFS * sizeof(uint32_t)) ||
 		(lut_tbl->sep_lut_size !=
-		 SEP_LUT_IDX * SEP_LUT_COEFFS * sizeof(uint32_t)))
-			return -EINVAL;
+		 SEP_LUT_IDX * SEP_LUT_COEFFS * sizeof(uint32_t))) {
+		mutex_unlock(&mdata->scaler_off->scaler_lock);
+		return -EINVAL;
+	}
 
 	if (!qseed3_lut_tbl->dir_lut) {
 		qseed3_lut_tbl->dir_lut = devm_kzalloc(&mdata->pdev->dev,
@@ -6646,7 +6650,7 @@ static int mdss_mdp_scaler_lut_init(struct mdss_data_type *mdata,
 				GFP_KERNEL);
 		if (!qseed3_lut_tbl->dir_lut) {
 			ret = -ENOMEM;
-			goto fail;
+			goto err;
 		}
 	}
 
@@ -6656,7 +6660,7 @@ static int mdss_mdp_scaler_lut_init(struct mdss_data_type *mdata,
 				GFP_KERNEL);
 		if (!qseed3_lut_tbl->cir_lut) {
 			ret = -ENOMEM;
-			goto fail;
+			goto fail_free_dir_lut;
 		}
 	}
 
@@ -6666,44 +6670,52 @@ static int mdss_mdp_scaler_lut_init(struct mdss_data_type *mdata,
 				GFP_KERNEL);
 		if (!qseed3_lut_tbl->sep_lut) {
 			ret = -ENOMEM;
-			goto fail;
+			goto fail_free_cir_lut;
 		}
 	}
 
 	/* Invalidate before updating */
 	qseed3_lut_tbl->valid = false;
 
-
 	if (copy_from_user(qseed3_lut_tbl->dir_lut,
 				(void *)(unsigned long)lut_tbl->dir_lut,
 				lut_tbl->dir_lut_size)) {
 			ret = -EINVAL;
-			goto err;
+			goto fail_free_sep_lut;
 	}
 
 	if (copy_from_user(qseed3_lut_tbl->cir_lut,
 				(void *)(unsigned long)lut_tbl->cir_lut,
 				lut_tbl->cir_lut_size)) {
 			ret = -EINVAL;
-			goto err;
+			goto fail_free_sep_lut;
 	}
 
 	if (copy_from_user(qseed3_lut_tbl->sep_lut,
 				(void *)(unsigned long)lut_tbl->sep_lut,
 				lut_tbl->sep_lut_size)) {
 			ret = -EINVAL;
-			goto err;
+			goto fail_free_sep_lut;
 	}
 
 	qseed3_lut_tbl->valid = true;
+	mutex_unlock(&mdata->scaler_off->scaler_lock);
+
 	return ret;
 
-fail:
-	kfree(qseed3_lut_tbl->dir_lut);
-	kfree(qseed3_lut_tbl->cir_lut);
-	kfree(qseed3_lut_tbl->sep_lut);
+fail_free_sep_lut:
+	devm_kfree(&mdata->pdev->dev, qseed3_lut_tbl->sep_lut);
+fail_free_cir_lut:
+	devm_kfree(&mdata->pdev->dev, qseed3_lut_tbl->cir_lut);
+fail_free_dir_lut:
+	devm_kfree(&mdata->pdev->dev, qseed3_lut_tbl->dir_lut);
 err:
+	qseed3_lut_tbl->dir_lut = NULL;
+	qseed3_lut_tbl->cir_lut = NULL;
+	qseed3_lut_tbl->sep_lut = NULL;
 	qseed3_lut_tbl->valid = false;
+	mutex_unlock(&mdata->scaler_off->scaler_lock);
+
 	return ret;
 }
 
diff --git a/drivers/video/fbdev/msm/mdss_mdp_pp.c b/drivers/video/fbdev/msm/mdss_mdp_pp.c
index 9c2b1d42bd35..ee338ba88c4d 100644
--- a/drivers/video/fbdev/msm/mdss_mdp_pp.c
+++ b/drivers/video/fbdev/msm/mdss_mdp_pp.c
@@ -1,4 +1,4 @@
-/* Copyright (c) 2012-2017, The Linux Foundation. All rights reserved.
+/* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 and
@@ -1604,11 +1604,16 @@ int mdss_mdp_scaler_lut_cfg(struct mdp_scale_data_v2 *scaler,
 	};
 
 	mdata = mdss_mdp_get_mdata();
+
+	mutex_lock(&mdata->scaler_off->scaler_lock);
+
 	lut_tbl = &mdata->scaler_off->lut_tbl;
 	if ((!lut_tbl) || (!lut_tbl->valid)) {
+		mutex_unlock(&mdata->scaler_off->scaler_lock);
 		pr_err("%s:Invalid QSEED3 LUT TABLE\n", __func__);
 		return -EINVAL;
 	}
+
 	if ((scaler->lut_flag & SCALER_LUT_DIR_WR) ||
 		(scaler->lut_flag & SCALER_LUT_Y_CIR_WR) ||
 		(scaler->lut_flag & SCALER_LUT_UV_CIR_WR) ||
@@ -1656,6 +1661,8 @@ int mdss_mdp_scaler_lut_cfg(struct mdp_scale_data_v2 *scaler,
 		}
 	}
 
+	mutex_unlock(&mdata->scaler_off->scaler_lock);
+
 	return 0;
 }