From 2903265e27bfc6dea915dd9e17a1b2587f621f73 Mon Sep 17 00:00:00 2001
From: Bart Van Assche <bvanassche@acm.org>
Date: Mon, 24 Jul 2023 13:08:29 -0700
Subject: [PATCH] scsi: ufs: Fix residual handling
Only call scsi_set_resid() in case of an underflow. Do not call
scsi_set_resid() in case of an overflow.
Cc: Avri Altman <avri.altman@wdc.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Fixes: cb38845d90fc ("scsi: ufs: core: Set the residual byte count")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20230724200843.3376570-2-bvanassche@acm.org
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
---
drivers/ufs/core/ufshcd.c | 12 ++++++++++--
include/ufs/ufs.h | 6 ++++++
2 files changed, 16 insertions(+), 2 deletions(-)
diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index c394dc50504ad..27e1a4914837c 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -5222,9 +5222,17 @@ ufshcd_transfer_rsp_status(struct ufs_hba *hba, struct ufshcd_lrb *lrbp,
int result = 0;
int scsi_status;
enum utp_ocs ocs;
+ u8 upiu_flags;
+ u32 resid;
- scsi_set_resid(lrbp->cmd,
- be32_to_cpu(lrbp->ucd_rsp_ptr->sr.residual_transfer_count));
+ upiu_flags = be32_to_cpu(lrbp->ucd_rsp_ptr->header.dword_0) >> 16;
+ resid = be32_to_cpu(lrbp->ucd_rsp_ptr->sr.residual_transfer_count);
+ /*
+ * Test !overflow instead of underflow to support UFS devices that do
+ * not set either flag.
+ */
+ if (resid && !(upiu_flags & UPIU_RSP_FLAG_OVERFLOW))
+ scsi_set_resid(lrbp->cmd, resid);
/* overall command status of utrd */
ocs = ufshcd_get_tr_ocs(lrbp, cqe);
diff --git a/include/ufs/ufs.h b/include/ufs/ufs.h
index 0dd546a20503b..c789252b5fad2 100644
--- a/include/ufs/ufs.h
+++ b/include/ufs/ufs.h
@@ -104,6 +104,12 @@ enum {
UPIU_CMD_FLAGS_READ = 0x40,
};
+/* UPIU response flags */
+enum {
+ UPIU_RSP_FLAG_UNDERFLOW = 0x20,
+ UPIU_RSP_FLAG_OVERFLOW = 0x40,
+};
+
/* UPIU Task Attributes */
enum {
UPIU_TASK_ATTR_SIMPLE = 0x00,
--
GitLab