From 11ea1de3fc4ba94127034cb01df63a666c4c9836 Mon Sep 17 00:00:00 2001 From: John Garry Date: Fri, 31 Oct 2025 13:39:13 -0700 Subject: scsi: core: Introduce .queue_reserved_command() Reserved commands will be used by SCSI LLDs for submitting internal commands. Since the SCSI host, target and device limits do not apply to the reserved command use cases, bypass the SCSI host limit checks for reserved commands. Introduce the .queue_reserved_command() callback for reserved commands. Additionally, do not activate the SCSI error handler if a reserved command fails such that reserved commands can be submitted from inside the SCSI error handler. [ bvanassche: modified patch title and patch description. Renamed .reserved_queuecommand() into .queue_reserved_command(). Changed the second argument of __blk_mq_end_request() from 0 into error code in the completion path if cmd->result != 0. Rewrote the scsi_queue_rq() changes. See also https://lore.kernel.org/linux-scsi/1666693096-180008-5-git-send-email-john.garry@huawei.com/ ] Cc: Hannes Reinecke Signed-off-by: John Garry Signed-off-by: Bart Van Assche Reviewed-by: Hannes Reinecke Link: https://patch.msgid.link/20251031204029.2883185-6-bvanassche@acm.org Signed-off-by: Martin K. Petersen --- include/scsi/scsi_host.h | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'include/scsi') diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h index 4f945a20d198..e87cf7eadd26 100644 --- a/include/scsi/scsi_host.h +++ b/include/scsi/scsi_host.h @@ -86,6 +86,12 @@ struct scsi_host_template { */ int (* queuecommand)(struct Scsi_Host *, struct scsi_cmnd *); + /* + * Queue a reserved command (BLK_MQ_REQ_RESERVED). The .queuecommand() + * documentation also applies to the .queue_reserved_command() callback. + */ + int (*queue_reserved_command)(struct Scsi_Host *, struct scsi_cmnd *); + /* * The commit_rqs function is used to trigger a hardware * doorbell after some requests have been queued with -- cgit v1.2.3