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From:   John Garry <john.garry@huawei.com>
To:     <axboe@kernel.dk>, <damien.lemoal@opensource.wdc.com>,
        <bvanassche@acm.org>, <hch@lst.de>, <jejb@linux.ibm.com>,
        <martin.petersen@oracle.com>, <hare@suse.de>, <satishkh@cisco.com>,
        <sebaddel@cisco.com>, <kartilak@cisco.com>
CC:     <linux-doc@vger.kernel.org>, <linux-rdma@vger.kernel.org>,
        <linux-mmc@vger.kernel.org>, <linux-nvme@lists.infradead.org>,
        <linux-s390@vger.kernel.org>, <linux-scsi@vger.kernel.org>,
        <mpi3mr-linuxdrv.pdl@broadcom.com>, <linux-block@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <nbd@other.debian.org>,
        John Garry <john.garry@huawei.com>
Subject: [PATCH v2 1/6] scsi: core: Remove reserved request time-out handling
Date:   Tue, 21 Jun 2022 19:15:38 +0800
Message-ID: <1655810143-67784-2-git-send-email-john.garry@huawei.com>
In-Reply-To: <1655810143-67784-1-git-send-email-john.garry@huawei.com>
References: <1655810143-67784-1-git-send-email-john.garry@huawei.com>
MIME-Version: 1.0
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Precedence: bulk

The SCSI core code does not currently support reserved commands. As such,
requests which time-out would never be reserved, and scsi_timeout()
'reserved' arg should never be set.

Remove handling for reserved requests, drop the wrapper scsi_timeout()
as it now just calls scsi_times_out() always, and finally rename
scsi_times_out() -> scsi_timeout() to match the blk_mq_ops method name.

Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
---
 Documentation/scsi/scsi_eh.rst          | 3 +--
 Documentation/scsi/scsi_mid_low_api.rst | 2 +-
 drivers/scsi/scsi_error.c               | 7 ++++---
 drivers/scsi/scsi_lib.c                 | 8 --------
 drivers/scsi/scsi_priv.h                | 3 ++-
 5 files changed, 8 insertions(+), 15 deletions(-)

diff --git a/Documentation/scsi/scsi_eh.rst b/Documentation/scsi/scsi_eh.rst
index 885395dc1f15..bad624fab823 100644
--- a/Documentation/scsi/scsi_eh.rst
+++ b/Documentation/scsi/scsi_eh.rst
@@ -87,8 +87,7 @@ with the command.
 1.2.2 Completing a scmd w/ timeout
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-The timeout handler is scsi_times_out().  When a timeout occurs, this
-function
+The timeout handler is scsi_timeout().  When a timeout occurs, this function
 
  1. invokes optional hostt->eh_timed_out() callback.  Return value can
     be one of
diff --git a/Documentation/scsi/scsi_mid_low_api.rst b/Documentation/scsi/scsi_mid_low_api.rst
index 63ddea2b9640..a8c5bd15a440 100644
--- a/Documentation/scsi/scsi_mid_low_api.rst
+++ b/Documentation/scsi/scsi_mid_low_api.rst
@@ -731,7 +731,7 @@ Details::
     *      Notes: If 'no_async_abort' is defined this callback
     *  	will be invoked from scsi_eh thread. No other commands
     *	will then be queued on current host during eh.
-    *	Otherwise it will be called whenever scsi_times_out()
+    *	Otherwise it will be called whenever scsi_timeout()
     *      is called due to a command timeout.
     *
     *      Optionally defined in: LLD
diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
index 49ef864df581..a8b71b73a5a5 100644
--- a/drivers/scsi/scsi_error.c
+++ b/drivers/scsi/scsi_error.c
@@ -139,7 +139,7 @@ static bool scsi_eh_should_retry_cmd(struct scsi_cmnd *cmd)
  *
  * Note: this function must be called only for a command that has timed out.
  * Because the block layer marks a request as complete before it calls
- * scsi_times_out(), a .scsi_done() call from the LLD for a command that has
+ * scsi_timeout(), a .scsi_done() call from the LLD for a command that has
  * timed out do not have any effect. Hence it is safe to call
  * scsi_finish_command() from this function.
  */
@@ -316,8 +316,9 @@ void scsi_eh_scmd_add(struct scsi_cmnd *scmd)
 }
 
 /**
- * scsi_times_out - Timeout function for normal scsi commands.
+ * scsi_timeout - Timeout function for normal scsi commands.
  * @req:	request that is timing out.
+ * @reserved:	whether the request is a reserved request.
  *
  * Notes:
  *     We do not need to lock this.  There is the potential for a race
@@ -325,7 +326,7 @@ void scsi_eh_scmd_add(struct scsi_cmnd *scmd)
  *     normal completion function determines that the timer has already
  *     fired, then it mustn't do anything.
  */
-enum blk_eh_timer_return scsi_times_out(struct request *req)
+enum blk_eh_timer_return scsi_timeout(struct request *req, bool reserved)
 {
 	struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(req);
 	enum blk_eh_timer_return rtn = BLK_EH_DONE;
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 6ffc9e4258a8..8eb51ef7c077 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -1790,14 +1790,6 @@ static blk_status_t scsi_queue_rq(struct blk_mq_hw_ctx *hctx,
 	return ret;
 }
 
-static enum blk_eh_timer_return scsi_timeout(struct request *req,
-		bool reserved)
-{
-	if (reserved)
-		return BLK_EH_RESET_TIMER;
-	return scsi_times_out(req);
-}
-
 static int scsi_mq_init_request(struct blk_mq_tag_set *set, struct request *rq,
 				unsigned int hctx_idx, unsigned int numa_node)
 {
diff --git a/drivers/scsi/scsi_priv.h b/drivers/scsi/scsi_priv.h
index 5c4786310a31..695d0c83ffe0 100644
--- a/drivers/scsi/scsi_priv.h
+++ b/drivers/scsi/scsi_priv.h
@@ -72,7 +72,8 @@ extern void scsi_exit_devinfo(void);
 
 /* scsi_error.c */
 extern void scmd_eh_abort_handler(struct work_struct *work);
-extern enum blk_eh_timer_return scsi_times_out(struct request *req);
+extern enum blk_eh_timer_return scsi_timeout(struct request *req,
+					     bool reserved);
 extern int scsi_error_handler(void *host);
 extern enum scsi_disposition scsi_decide_disposition(struct scsi_cmnd *cmd);
 extern void scsi_eh_wakeup(struct Scsi_Host *shost);
-- 
2.25.1