From 3b3bec886689de128a2556759e856f1a9d27f64a Mon Sep 17 00:00:00 2001
From: Jaegeuk Kim <jaegeuk@google.com>
Date: Mon, 28 Jun 2021 00:05:01 -0700
Subject: [PATCH] Revert "Revert "KMI: BACKPORT: FROMGIT: scsi: ufs: Optimize
 host lock on transfer requests send/compl paths""

This reverts commit 850f11aa85f055dd914928b7aea2e99319800459.

We need to go back upstream version with right fix.

Bug: 192095860
Signed-off-by: Jaegeuk Kim <jaegeuk@google.com>
Change-Id: I26bf924125f06e97c1262578c99a2dbb58394235
---
 drivers/scsi/ufs/ufshcd.c | 15 +++++++++------
 drivers/scsi/ufs/ufshcd.h |  2 ++
 2 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 6656c98c7cd2..c2b862f81d2b 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -2665,7 +2665,7 @@ static int ufshcd_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd)
 		(hba->clk_gating.state != CLKS_ON));
 
 	lrbp = &hba->lrb[tag];
-	if (unlikely(test_bit(tag, &hba->outstanding_reqs))) {
+	if (unlikely(lrbp->in_use)) {
 		if (hba->pm_op_in_progress)
 			set_host_byte(cmd, DID_BAD_TARGET);
 		else
@@ -2925,7 +2925,7 @@ static int ufshcd_exec_dev_cmd(struct ufs_hba *hba,
 
 	init_completion(&wait);
 	lrbp = &hba->lrb[tag];
-	if (unlikely(test_bit(tag, &hba->outstanding_reqs))) {
+	if (unlikely(lrbp->in_use)) {
 		err = -EBUSY;
 		goto out;
 	}
@@ -5134,9 +5134,8 @@ static void __ufshcd_transfer_req_compl(struct ufs_hba *hba,
 	bool update_scaling = false;
 
 	for_each_set_bit(index, &completed_reqs, hba->nutrs) {
-		if (!test_and_clear_bit(index, &hba->outstanding_reqs))
-			continue;
 		lrbp = &hba->lrb[index];
+		lrbp->in_use = false;
 		lrbp->compl_time_stamp = ktime_get();
 		cmd = lrbp->cmd;
 		if (cmd) {
@@ -5168,6 +5167,9 @@ static void __ufshcd_transfer_req_compl(struct ufs_hba *hba,
 			hba->clk_scaling.active_reqs--;
 	}
 
+	/* clear corresponding bits of completed commands */
+	hba->outstanding_reqs ^= completed_reqs;
+
 	ufshcd_clk_scaling_update_busy(hba);
 }
 
@@ -6601,11 +6603,11 @@ static int ufshcd_issue_devman_upiu_cmd(struct ufs_hba *hba,
 	WARN_ON_ONCE(!ufshcd_valid_tag(hba, tag));
 
 	init_completion(&wait);
-	if (unlikely(test_bit(tag, &hba->outstanding_reqs))) {
+	lrbp = &hba->lrb[tag];
+	if (unlikely(lrbp->in_use)) {
 		err = -EBUSY;
 		goto out;
 	}
-	lrbp = &hba->lrb[tag];
 
 	WARN_ON(lrbp->cmd);
 	lrbp->cmd = NULL;
@@ -6974,6 +6976,7 @@ static int ufshcd_abort(struct scsi_cmnd *cmd)
 		if (lrbp->cmd) {
 			__ufshcd_transfer_req_compl(hba, (1UL << tag));
 			__set_bit(tag, &hba->outstanding_reqs);
+			lrbp->in_use = true;
 			hba->force_reset = true;
 			ufshcd_schedule_eh_work(hba);
 		}
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index 0c70f8a8c158..9ce98969446c 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -188,6 +188,7 @@ struct ufs_pm_lvl_states {
  * @crypto_key_slot: the key slot to use for inline crypto (-1 if none)
  * @data_unit_num: the data unit number for the first block for inline crypto
  * @req_abort_skip: skip request abort task flag
+ * @in_use: indicates that this lrb is still in use
  */
 struct ufshcd_lrb {
 	struct utp_transfer_req_desc *utr_descriptor_ptr;
@@ -217,6 +218,7 @@ struct ufshcd_lrb {
 #endif
 
 	bool req_abort_skip;
+	bool in_use;
 };
 
 /**