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From:   Bean Huo <huobean@gmail.com>
To:     alim.akhtar@samsung.com, avri.altman@wdc.com,
        asutoshd@codeaurora.org, jejb@linux.ibm.com,
        martin.petersen@oracle.com, stanley.chu@mediatek.com,
        beanhuo@micron.com, bvanassche@acm.org, tomas.winkler@intel.com,
        cang@codeaurora.org
Cc:     linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org,
        rjw@rjwysocki.net
Subject: [PATCH v2 2/3] scsi: ufs: Add handling of the return value of pm_runtime_get_sync()
Date:   Thu, 24 Dec 2020 18:20:09 +0100
Message-Id: <20201224172010.10701-3-huobean@gmail.com>
In-Reply-To: <20201224172010.10701-1-huobean@gmail.com>
References: <20201224172010.10701-1-huobean@gmail.com>
Precedence: bulk

From: Bean Huo <beanhuo@micron.com>

The race issue may exist between UFS access in UFS sysfs context and UFS
shutdown, thus will cause pm_runtime_get_sync() resume failure.
Add handling of the return value of pm_runtime_get_sync(). Let it return
in case pm_runtime_get_sync() resume failed.

Signed-off-by: Bean Huo <beanhuo@micron.com>
---
 drivers/scsi/ufs/ufs-sysfs.c | 38 ++++++++++++++++++++++++++++++------
 1 file changed, 32 insertions(+), 6 deletions(-)

diff --git a/drivers/scsi/ufs/ufs-sysfs.c b/drivers/scsi/ufs/ufs-sysfs.c
index 0e1438485133..8e5e36e01bee 100644
--- a/drivers/scsi/ufs/ufs-sysfs.c
+++ b/drivers/scsi/ufs/ufs-sysfs.c
@@ -154,12 +154,17 @@ static ssize_t auto_hibern8_show(struct device *dev,
 				 struct device_attribute *attr, char *buf)
 {
 	u32 ahit;
+	int ret;
 	struct ufs_hba *hba = dev_get_drvdata(dev);
 
 	if (!ufshcd_is_auto_hibern8_supported(hba))
 		return -EOPNOTSUPP;
 
-	pm_runtime_get_sync(hba->dev);
+	ret = pm_runtime_get_sync(hba->dev);
+	if (ret < 0) {
+		pm_runtime_put_noidle(hba->dev);
+		return ret;
+	}
 	ufshcd_hold(hba, false);
 	ahit = ufshcd_readl(hba, REG_AUTO_HIBERNATE_IDLE_TIMER);
 	ufshcd_release(hba);
@@ -225,7 +230,12 @@ static ssize_t ufs_sysfs_read_desc_param(struct ufs_hba *hba,
 	if (param_size > 8)
 		return -EINVAL;
 
-	pm_runtime_get_sync(hba->dev);
+	ret = pm_runtime_get_sync(hba->dev);
+	if (ret < 0) {
+		pm_runtime_put_noidle(hba->dev);
+		return ret;
+	}
+
 	ret = ufshcd_read_desc_param(hba, desc_id, desc_index,
 				param_offset, desc_buf, param_size);
 	pm_runtime_put_sync(hba->dev);
@@ -594,7 +604,11 @@ static ssize_t _name##_show(struct device *dev,				\
 	desc_buf = kzalloc(QUERY_DESC_MAX_SIZE, GFP_ATOMIC);		\
 	if (!desc_buf)                                                  \
 		return -ENOMEM;                                         \
-	pm_runtime_get_sync(hba->dev);					\
+	ret = pm_runtime_get_sync(hba->dev);				\
+	if (ret < 0) {							\
+		pm_runtime_put_noidle(hba->dev);			\
+		return ret;						\
+	}								\
 	ret = ufshcd_query_descriptor_retry(hba,			\
 		UPIU_QUERY_OPCODE_READ_DESC, QUERY_DESC_IDN_DEVICE,	\
 		0, 0, desc_buf, &desc_len);				\
@@ -653,7 +667,11 @@ static ssize_t _name##_show(struct device *dev,				\
 	struct ufs_hba *hba = dev_get_drvdata(dev);			\
 	if (ufshcd_is_wb_flags(QUERY_FLAG_IDN##_uname))			\
 		index = ufshcd_wb_get_query_index(hba);			\
-	pm_runtime_get_sync(hba->dev);					\
+	ret = pm_runtime_get_sync(hba->dev);				\
+	if (ret < 0) {							\
+		pm_runtime_put_noidle(hba->dev);			\
+		return ret;						\
+	}								\
 	ret = ufshcd_query_flag(hba, UPIU_QUERY_OPCODE_READ_FLAG,	\
 		QUERY_FLAG_IDN##_uname, index, &flag);			\
 	pm_runtime_put_sync(hba->dev);					\
@@ -711,7 +729,11 @@ static ssize_t _name##_show(struct device *dev,				\
 	u8 index = 0;							\
 	if (ufshcd_is_wb_attrs(QUERY_ATTR_IDN##_uname))			\
 		index = ufshcd_wb_get_query_index(hba);			\
-	pm_runtime_get_sync(hba->dev);					\
+	ret = pm_runtime_get_sync(hba->dev);				\
+	if (ret < 0) {							\
+		pm_runtime_put_noidle(hba->dev);			\
+		return ret;						\
+	}								\
 	ret = ufshcd_query_attr(hba, UPIU_QUERY_OPCODE_READ_ATTR,	\
 		QUERY_ATTR_IDN##_uname, index, 0, &value);		\
 	pm_runtime_put_sync(hba->dev);					\
@@ -850,7 +872,11 @@ static ssize_t dyn_cap_needed_attribute_show(struct device *dev,
 	u8 lun = ufshcd_scsi_to_upiu_lun(sdev->lun);
 	int ret;
 
-	pm_runtime_get_sync(hba->dev);
+	ret = pm_runtime_get_sync(hba->dev);
+	if (ret < 0) {
+		pm_runtime_put_noidle(hba->dev);
+		return ret;
+	}
 	ret = ufshcd_query_attr(hba, UPIU_QUERY_OPCODE_READ_ATTR,
 		QUERY_ATTR_IDN_DYN_CAP_NEEDED, lun, 0, &value);
 	pm_runtime_put_sync(hba->dev);
-- 
2.17.1