msm: camera: common: Resolve potential data race conditions

Add locks before shared variable access in request manager, csid driver
and smmu appi files to avoid data race conditions.

CRs-Fixed: 3348931
Change-Id: Ifa860bf157047f23bd2bc460a16e9405de0d5c83
Signed-off-by: Dharmender Sharma <quic_dharshar@quicinc.com>

drivers/cam_isp/isp_hw_mgr/isp_hw/ife_csid_hw/cam_ife_csid_hw_ver1.c

@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0-only
 /*
  * Copyright (c) 2020-2021, The Linux Foundation. All rights reserved.
- * Copyright (c) 2022 Qualcomm Innovation Center, Inc. All rights reserved.
+ * Copyright (c) 2022-2023 Qualcomm Innovation Center, Inc. All rights reserved.
  */
 
 #include <linux/iopoll.h>
@@ -2619,10 +2619,13 @@ static int cam_ife_csid_ver1_enable_hw(struct cam_ife_csid_ver1_hw *csid_hw)
 			csid_hw->core_info->csid_reg;
 	soc_info = &csid_hw->hw_info->soc_info;
 
+	mutex_lock(&csid_hw->hw_info->hw_mutex);
+
 	/* overflow check before increment */
 	if (csid_hw->hw_info->open_count == UINT_MAX) {
 		CAM_ERR(CAM_ISP, "CSID:%d Open count reached max",
 			csid_hw->hw_intf->hw_idx);
+			mutex_unlock(&csid_hw->hw_info->hw_mutex);
 		return -EINVAL;
 	}
 
@@ -2631,8 +2634,10 @@ static int cam_ife_csid_ver1_enable_hw(struct cam_ife_csid_ver1_hw *csid_hw)
 
 	if (csid_hw->hw_info->open_count > 1) {
 		CAM_DBG(CAM_ISP, "CSID hw has already been enabled");
+		mutex_unlock(&csid_hw->hw_info->hw_mutex);
 		return rc;
 	}
+	mutex_unlock(&csid_hw->hw_info->hw_mutex);
 
 	rc = cam_soc_util_get_clk_level(soc_info, csid_hw->clk_rate,
 		soc_info->src_clk_idx, &clk_lvl);
@@ -2709,7 +2714,9 @@ disable_soc:
 	cam_ife_csid_disable_soc_resources(soc_info);
 	csid_hw->hw_info->hw_state = CAM_HW_STATE_POWER_DOWN;
 err:
+	mutex_lock(&csid_hw->hw_info->hw_mutex);
 	csid_hw->hw_info->open_count--;
+	mutex_unlock(&csid_hw->hw_info->hw_mutex);
 	return rc;
 }
 
@@ -2851,17 +2858,22 @@ static int cam_ife_csid_ver1_disable_hw(
 	int rc = 0;
 	unsigned long                             flags;
 
+	mutex_lock(&csid_hw->hw_info->hw_mutex);
 	/* Check for refcount */
 	if (!csid_hw->hw_info->open_count) {
 		CAM_WARN(CAM_ISP, "Unbalanced disable_hw");
+		mutex_unlock(&csid_hw->hw_info->hw_mutex);
 		return rc;
 	}
 
 	/* Decrement ref Count */
 	csid_hw->hw_info->open_count--;
 
-	if (csid_hw->hw_info->open_count)
+	if (csid_hw->hw_info->open_count) {
+		mutex_unlock(&csid_hw->hw_info->hw_mutex);
 		return rc;
+	}
+	mutex_unlock(&csid_hw->hw_info->hw_mutex);
 
 	soc_info = &csid_hw->hw_info->soc_info;
 	csid_reg = (struct cam_ife_csid_ver1_reg_info *)

drivers/cam_req_mgr/cam_req_mgr_core.c

@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0-only
 /*
  * Copyright (c) 2016-2021, The Linux Foundation. All rights reserved.
- * Copyright (c) 2022 Qualcomm Innovation Center, Inc. All rights reserved.
+ * Copyright (c) 2022-2023 Qualcomm Innovation Center, Inc. All rights reserved.
  */
 
 #include <linux/module.h>
@@ -47,7 +47,9 @@ void cam_req_mgr_core_link_reset(struct cam_req_mgr_core_link *link)
 	link->req.l_tbl = NULL;
 	link->req.num_tbl = 0;
 	link->watchdog = NULL;
+	spin_lock_bh(&link->link_state_spin_lock);
 	link->state = CAM_CRM_LINK_STATE_AVAILABLE;
+	spin_unlock_bh(&link->link_state_spin_lock);
 	link->parent = NULL;
 	link->sync_link_sof_skip = false;
 	link->open_req_cnt = 0;
@@ -71,7 +73,9 @@ void cam_req_mgr_core_link_reset(struct cam_req_mgr_core_link *link)
 	link->try_for_internal_recovery = false;
 	link->is_sending_req = false;
 	atomic_set(&link->eof_event_cnt, 0);
+	mutex_lock(&link->lock);
 	link->properties_mask = CAM_LINK_PROPERTY_NONE;
+	mutex_unlock(&link->lock);
 	link->cont_empty_slots = 0;
 	__cam_req_mgr_reset_apply_data(link);
 
@@ -1810,11 +1814,14 @@ static int __cam_req_mgr_check_multi_sync_link_ready(
 {
 	int i, rc = 0;
 
+	spin_lock_bh(&link->link_state_spin_lock);
 	if (link->state == CAM_CRM_LINK_STATE_IDLE) {
+		spin_unlock_bh(&link->link_state_spin_lock);
 		CAM_ERR(CAM_CRM, "link hdl %x is in idle state",
 				link->link_hdl);
 		return -EINVAL;
 	}
+	spin_unlock_bh(&link->link_state_spin_lock);
 
 	for (i = 0; i < num_sync_links; i++) {
 		if (sync_link[i]) {
@@ -2689,7 +2696,11 @@ static struct cam_req_mgr_core_link *__cam_req_mgr_reserve_link(
 		sizeof(struct cam_req_mgr_slot) * MAX_REQ_SLOTS);
 	link->req.in_q = in_q;
 	in_q->num_slots = 0;
+
+	spin_lock_bh(&link->link_state_spin_lock);
 	link->state = CAM_CRM_LINK_STATE_IDLE;
+	spin_unlock_bh(&link->link_state_spin_lock);
+
 	link->parent = (void *)session;
 	link->is_sending_req = false;
 
@@ -5170,7 +5181,9 @@ int cam_req_mgr_link_control(struct cam_req_mgr_link_control *control)
 			/* Wait for the streaming of sync link */
 			link->initial_skip = true;
 			/* Pause the timer before sensor stream on */
+			spin_lock_bh(&link->link_state_spin_lock);
 			link->watchdog->pause_timer = true;
+			spin_unlock_bh(&link->link_state_spin_lock);
 			/* notify nodes */
 			__cam_req_mgr_send_evt(0, CAM_REQ_MGR_LINK_EVT_RESUME,
 				CRM_KMD_ERR_MAX, link);
@@ -5216,13 +5229,16 @@ int cam_req_mgr_link_properties(struct cam_req_mgr_link_properties *properties)
 		goto end;
 	}
 
+	spin_lock_bh(&link->link_state_spin_lock);
 	if (link->state != CAM_CRM_LINK_STATE_READY) {
+		spin_unlock_bh(&link->link_state_spin_lock);
 		CAM_ERR(CAM_CRM,
 			"Only can config link 0x%x properties in ready state",
 			link->link_hdl);
 		rc = -EAGAIN;
 		goto end;
 	}
+	spin_unlock_bh(&link->link_state_spin_lock);
 
 	mutex_lock(&link->lock);
 	link->properties_mask = properties->properties_mask;

drivers/cam_smmu/cam_smmu_api.c

@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0-only
 /*
  * Copyright (c) 2014-2021, The Linux Foundation. All rights reserved.
- * Copyright (c) 2022 Qualcomm Innovation Center, Inc. All rights reserved.
+ * Copyright (c) 2022-2023 Qualcomm Innovation Center, Inc. All rights reserved.
  */
 
 #include <linux/module.h>
@@ -1111,6 +1111,11 @@ void cam_smmu_reset_iommu_table(enum cam_smmu_init_dir ops)
 	int j = 0;
 
 	for (i = 0; i < iommu_cb_set.cb_num; i++) {
+		if (ops == CAM_SMMU_TABLE_INIT)
+			mutex_init(&iommu_cb_set.cb_info[i].lock);
+
+		mutex_lock(&iommu_cb_set.cb_info[i].lock);
+
 		iommu_cb_set.cb_info[i].handle = HANDLE_INIT;
 		INIT_LIST_HEAD(&iommu_cb_set.cb_info[i].smmu_buf_list);
 		INIT_LIST_HEAD(&iommu_cb_set.cb_info[i].smmu_buf_kernel_list);
@@ -1122,9 +1127,10 @@ void cam_smmu_reset_iommu_table(enum cam_smmu_init_dir ops)
 			iommu_cb_set.cb_info[i].token[j] = NULL;
 			iommu_cb_set.cb_info[i].handler[j] = NULL;
 		}
-		if (ops == CAM_SMMU_TABLE_INIT)
-			mutex_init(&iommu_cb_set.cb_info[i].lock);
-		else
+
+		mutex_unlock(&iommu_cb_set.cb_info[i].lock);
+
+		if (ops != CAM_SMMU_TABLE_INIT)
 			mutex_destroy(&iommu_cb_set.cb_info[i].lock);
 	}
 }