[v1,1/1] scsi: ufs: core: Fix ufshcd_inc_sq_tail function bug

Commit Message

Zhang Hui June 1, 2023, 9:13 a.m. UTC

From: zhanghui <[e-mail]>

If q->max_entries is not multiple of 32, mask not every bit is 1.
So q->sq_tail_slot some bit will be cleared by use this way.

Signed-off-by: zhanghui <[e-mail]>
---
 drivers/ufs/core/ufshcd-priv.h | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

Comments

Bao D. Nguyen June 1, 2023, 10:27 a.m. UTC | #1

On 6/1/2023 2:13 AM, Zhang Hui wrote:
> From: zhanghui <[e-mail]>
> 
> If q->max_entries is not multiple of 32, mask not every bit is 1.
> So q->sq_tail_slot some bit will be cleared by use this way.
Hi Zhang,
Maybe reword the commit message a little bit? Otherwise, it is a good patch.

Reviewed-by: Bao D. Nguyen <[e-mail]>

Patch

diff --git a/drivers/ufs/core/ufshcd-priv.h b/drivers/ufs/core/ufshcd-priv.h
index d53b93c21a0c..319fba31c1f5 100644
--- a/drivers/ufs/core/ufshcd-priv.h
+++ b/drivers/ufs/core/ufshcd-priv.h
@@ -366,10 +366,11 @@  static inline bool ufs_is_valid_unit_desc_lun(struct ufs_dev_info *dev_info, u8
 static inline void ufshcd_inc_sq_tail(struct ufs_hw_queue *q)
 	__must_hold(&q->sq_lock)
 {
-	u32 mask = q->max_entries - 1;
 	u32 val;
 
-	q->sq_tail_slot = (q->sq_tail_slot + 1) & mask;
+	q->sq_tail_slot++;
+	if (q->sq_tail_slot == q->max_entries)
+		q->sq_tail_slot = 0;
 	val = q->sq_tail_slot * sizeof(struct utp_transfer_req_desc);
 	writel(val, q->mcq_sq_tail);
 }