From 1b22cfb14142aba7742d307c4f8d7006f919308c Mon Sep 17 00:00:00 2001 From: Damien Le Moal Date: Thu, 11 May 2023 03:13:42 +0200 Subject: scsi: core: Allow enabling and disabling command duration limits Add the sysfs scsi_device attribute cdl_enable to allow a user to enable or disable a device command duration limits feature. CDL is disabled by default. This feature must be explicitly enabled by a user by setting the cdl_enable attribute to 1. The new function scsi_cdl_enable() does not do anything beside setting the cdl_enable field of struct scsi_device in the case of a (real) SCSI device (e.g. a SAS HDD). For ATA devices, the command duration limits feature needs to be enabled/disabled using the ATA feature sub-page of the control mode page. To do so, the scsi_cdl_enable() function checks if this mode page is supported using scsi_mode_sense(). If it is, scsi_mode_select() is used to enable and disable CDL. Signed-off-by: Damien Le Moal Reviewed-by: Hannes Reinecke Co-developed-by: Niklas Cassel Signed-off-by: Niklas Cassel Link: https://lore.kernel.org/r/20230511011356.227789-10-nks@flawful.org Signed-off-by: Martin K. Petersen --- include/scsi/scsi_device.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/scsi/scsi_device.h') diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h index 6b8df9e253a0..b2cdb078b7bd 100644 --- a/include/scsi/scsi_device.h +++ b/include/scsi/scsi_device.h @@ -219,6 +219,7 @@ struct scsi_device { unsigned no_vpd_size:1; /* No VPD size reported in header */ unsigned cdl_supported:1; /* Command duration limits supported */ + unsigned cdl_enable:1; /* Enable/disable Command duration limits */ unsigned int queue_stopped; /* request queue is quiesced */ bool offline_already; /* Device offline message logged */ @@ -367,6 +368,7 @@ extern void scsi_remove_device(struct scsi_device *); extern int scsi_unregister_device_handler(struct scsi_device_handler *scsi_dh); void scsi_attach_vpd(struct scsi_device *sdev); void scsi_cdl_check(struct scsi_device *sdev); +int scsi_cdl_enable(struct scsi_device *sdev, bool enable); extern struct scsi_device *scsi_device_from_queue(struct request_queue *q); extern int __must_check scsi_device_get(struct scsi_device *); -- cgit v1.2.3