scsi: ufs: core: Fix ufshcd_inc_sq_tail() function bug

When qdepth is not power of 2, not every bit of the mask is 1, so
in sq_tail_slot some bits will be cleared unexpectedly.

Signed-off-by: zhanghui <zhanghui31@xiaomi.com>
Link: https://lore.kernel.org/r/20230601124613.1446-1-zhanghui31@xiaomi.com
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/ufs/core/ufshcd-priv.h b/drivers/ufs/core/ufshcd-priv.h
index f32c1a8..aa88e60 100644 (file)
--- a/drivers/ufs/core/ufshcd-priv.h
+++ b/drivers/ufs/core/ufshcd-priv.h
@@ -369,10 +369,11 @@ 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);
 }