[PATCH v4 2/6] scsi: ufs: core: Add a helper for clearing hba->outstanding_reqs

[Stanley Jhu]

ufshcd_poll() and ufshcd_abort() each have their own copy of the code
that clears bits in hba->outstanding_reqs under hba->outstanding_lock.

Move that code into ufshcd_clear_outstanding_reqs() and its locked
variant __ufshcd_clear_outstanding_reqs(), and use them in both
functions. No functional change.

Cc: stable@xxxxxxxxxxxxxxx
Link: https://lore.kernel.org/r/3779e125-9acc-42c8-9489-51b9e3c6716d@xxxxxxx
Suggested-by: Bart Van Assche <bvanassche@xxxxxxx>
Reviewed-by: Bean Huo <beanhuo@xxxxxxxxxx>
Reviewed-by: Peter Wang <peter.wang@xxxxxxxxxxxx>
Signed-off-by: Stanley Jhu <stanleyjhu@xxxxxxxxxx>
---
 drivers/ufs/core/ufshcd.c | 48 +++++++++++++++++++++++++++++----------
 1 file changed, 36 insertions(+), 12 deletions(-)

diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index 12aafcf1f9b3..1db572f84971 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -6052,6 +6052,37 @@ static void ufshcd_clear_polled(struct ufs_hba *hba,
 	}
 }
 
+/*
+ * Return a bitmask of the transfer requests cleared from
+ * @hba->outstanding_reqs.
+ */
+static unsigned long __ufshcd_clear_outstanding_reqs(struct ufs_hba *hba,
+						     unsigned long mask,
+						     bool from_irq)
+	__must_hold(&hba->outstanding_lock)
+{
+	unsigned long completed_reqs = mask & hba->outstanding_reqs;
+
+	if (from_irq) {
+		/* Do not complete polled requests from interrupt context. */
+		ufshcd_clear_polled(hba, &completed_reqs);
+	}
+	hba->outstanding_reqs &= ~completed_reqs;
+
+	return completed_reqs;
+}
+
+/*
+ * Return a bitmask of the transfer requests cleared from
+ * @hba->outstanding_reqs.
+ */
+static unsigned long ufshcd_clear_outstanding_reqs(struct ufs_hba *hba,
+						   unsigned long mask)
+{
+	guard(spinlock_irqsave)(&hba->outstanding_lock);
+	return __ufshcd_clear_outstanding_reqs(hba, mask, false);
+}
+
 /*
  * Return: > 0 if one or more commands have been completed or 0 if no
  * requests have been completed.
@@ -6062,6 +6093,7 @@ static int ufshcd_poll(struct Scsi_Host *shost, unsigned int queue_num)
 	unsigned long completed_reqs, flags;
 	u32 tr_doorbell;
 	struct ufs_hw_queue *hwq;
+	bool from_irq;
 
 	if (hba->mcq_enabled) {
 		hwq = &hba->uhq[queue_num];
@@ -6071,12 +6103,9 @@ static int ufshcd_poll(struct Scsi_Host *shost, unsigned int queue_num)
 
 	spin_lock_irqsave(&hba->outstanding_lock, flags);
 	tr_doorbell = ufshcd_readl(hba, REG_UTP_TRANSFER_REQ_DOOR_BELL);
-	completed_reqs = ~tr_doorbell & hba->outstanding_reqs;
-	if (queue_num == UFSHCD_POLL_FROM_INTERRUPT_CONTEXT) {
-		/* Do not complete polled requests from interrupt context. */
-		ufshcd_clear_polled(hba, &completed_reqs);
-	}
-	hba->outstanding_reqs &= ~completed_reqs;
+	from_irq = queue_num == UFSHCD_POLL_FROM_INTERRUPT_CONTEXT;
+	completed_reqs = __ufshcd_clear_outstanding_reqs(hba, ~tr_doorbell,
+							 from_irq);
 	spin_unlock_irqrestore(&hba->outstanding_lock, flags);
 
 	if (completed_reqs)
@@ -8111,7 +8140,6 @@ static int ufshcd_abort(struct scsi_cmnd *cmd)
 	struct ufshcd_lrb *lrbp = scsi_cmd_priv(cmd);
 	unsigned long flags;
 	int err = FAILED;
-	bool outstanding;
 	u32 reg;
 
 	ufshcd_hold(hba);
@@ -8206,11 +8234,7 @@ static int ufshcd_abort(struct scsi_cmnd *cmd)
 	 * Clear the corresponding bit from outstanding_reqs since the command
 	 * has been aborted successfully.
 	 */
-	spin_lock_irqsave(&hba->outstanding_lock, flags);
-	outstanding = __test_and_clear_bit(tag, &hba->outstanding_reqs);
-	spin_unlock_irqrestore(&hba->outstanding_lock, flags);
-
-	if (outstanding)
+	if (ufshcd_clear_outstanding_reqs(hba, BIT(tag)))
 		ufshcd_release_scsi_cmd(hba, cmd);
 
 	err = SUCCESS;
-- 
2.56.0.212.g129ede20d9-goog