scsi: drop reason argument from ->change_queue_depth

Drop the now unused reason argument from the ->change_queue_depth method.
Also add a return value to scsi_adjust_queue_depth, and rename it to
scsi_change_queue_depth now that it can be used as the default
->change_queue_depth implementation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>

73 files changed, 155 insertions, 412 deletions

diff --git a/Documentation/scsi/scsi_mid_low_api.txt b/Documentation/scsi/scsi_mid_low_api.txt
index bee7d86b9dcc..731bc4f4c5e6 100644
--- a/Documentation/scsi/scsi_mid_low_api.txt
+++ b/Documentation/scsi/scsi_mid_low_api.txt
@@ -149,7 +149,7 @@ scsi_add_host()  ---->
 scsi_scan_host()  -------+
                          |
                     slave_alloc()
-                    slave_configure() -->  scsi_adjust_queue_depth()
+                    slave_configure() -->  scsi_change_queue_depth()
                          |
                     slave_alloc()
                     slave_configure()
@@ -159,7 +159,7 @@ scsi_scan_host()  -------+
 ------------------------------------------------------------
 
 If the LLD wants to adjust the default queue settings, it can invoke
-scsi_adjust_queue_depth() in its slave_configure() routine.
+scsi_change_queue_depth() in its slave_configure() routine.
 
 *** For scsi devices that the mid level tries to scan but do not
     respond, a slave_alloc(), slave_destroy() pair is called.
@@ -203,7 +203,7 @@ LLD                   mid level                    LLD
 scsi_add_device()  ------+
                          |
                     slave_alloc()
-                    slave_configure()   [--> scsi_adjust_queue_depth()]
+                    slave_configure()   [--> scsi_change_queue_depth()]
 ------------------------------------------------------------
 
 In a similar fashion, an LLD may become aware that a SCSI device has been
@@ -261,7 +261,7 @@ init_this_scsi_driver() ----+
                             |                scsi_register()
                             |
                       slave_alloc()
-                      slave_configure()  -->  scsi_adjust_queue_depth()
+                      slave_configure()  -->  scsi_change_queue_depth()
                       slave_alloc()   ***
                       slave_destroy() ***
                             |
@@ -271,7 +271,7 @@ init_this_scsi_driver() ----+
                       slave_destroy() ***
 ------------------------------------------------------------
 
-The mid level invokes scsi_adjust_queue_depth() with "cmd_per_lun" for that
+The mid level invokes scsi_change_queue_depth() with "cmd_per_lun" for that
 host as the queue length. These settings can be overridden by a
 slave_configure() supplied by the LLD.
 
@@ -368,7 +368,7 @@ names all start with "scsi_".
 Summary:
    scsi_add_device - creates new scsi device (lu) instance
    scsi_add_host - perform sysfs registration and set up transport class
-   scsi_adjust_queue_depth - change the queue depth on a SCSI device
+   scsi_change_queue_depth - change the queue depth on a SCSI device
    scsi_bios_ptable - return copy of block device's partition table
    scsi_block_requests - prevent further commands being queued to given host
    scsi_host_alloc - return a new scsi_host instance whose refcount==1
@@ -436,7 +436,7 @@ int scsi_add_host(struct Scsi_Host *shost, struct device * dev)
 
 
 /**
- * scsi_adjust_queue_depth - allow LLD to change queue depth on a SCSI device
+ * scsi_change_queue_depth - allow LLD to change queue depth on a SCSI device
  * @sdev:       pointer to SCSI device to change queue depth on
  * @tags        Number of tags allowed if tagged queuing enabled,
  *              or number of commands the LLD can queue up
@@ -453,7 +453,7 @@ int scsi_add_host(struct Scsi_Host *shost, struct device * dev)
  *      Defined in: drivers/scsi/scsi.c [see source code for more notes]
  *
  **/
-void scsi_adjust_queue_depth(struct scsi_device *sdev, int tags)
+int scsi_change_queue_depth(struct scsi_device *sdev, int tags)
 
 
 /**
@@ -1214,7 +1214,7 @@ of interest:
                    for disk firmware uploads.
     cmd_per_lun  - maximum number of commands that can be queued on devices
                    controlled by the host. Overridden by LLD calls to
-                   scsi_adjust_queue_depth().
+                   scsi_change_queue_depth().
     unchecked_isa_dma - 1=>only use bottom 16 MB of ram (ISA DMA addressing
                    restriction), 0=>can use full 32 bit (or better) DMA
                    address space
@@ -1254,7 +1254,7 @@ struct scsi_cmnd
 Instances of this structure convey SCSI commands to the LLD and responses
 back to the mid level. The SCSI mid level will ensure that no more SCSI
 commands become queued against the LLD than are indicated by
-scsi_adjust_queue_depth() (or struct Scsi_Host::cmd_per_lun). There will
+scsi_change_queue_depth() (or struct Scsi_Host::cmd_per_lun). There will
 be at least one instance of struct scsi_cmnd available for each SCSI device.
 Members of interest:
     cmnd         - array containing SCSI command
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index c8bb6abbf12c..de46385dbe71 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -1164,7 +1164,7 @@ static int ata_scsi_dev_config(struct scsi_device *sdev,
 
 		depth = min(sdev->host->can_queue, ata_id_queue_depth(dev->id));
 		depth = min(ATA_MAX_QUEUE - 1, depth);
-		scsi_adjust_queue_depth(sdev, depth);
+		scsi_change_queue_depth(sdev, depth);
 	}
 
 	blk_queue_flush_queueable(q, false);
@@ -1243,21 +1243,17 @@ void ata_scsi_slave_destroy(struct scsi_device *sdev)
  *	@ap: ATA port to which the device change the queue depth
  *	@sdev: SCSI device to configure queue depth for
  *	@queue_depth: new queue depth
- *	@reason: calling context
  *
  *	libsas and libata have different approaches for associating a sdev to
  *	its ata_port.
  *
  */
 int __ata_change_queue_depth(struct ata_port *ap, struct scsi_device *sdev,
-			     int queue_depth, int reason)
+			     int queue_depth)
 {
 	struct ata_device *dev;
 	unsigned long flags;
 
-	if (reason != SCSI_QDEPTH_DEFAULT)
-		return -EOPNOTSUPP;
-
 	if (queue_depth < 1 || queue_depth == sdev->queue_depth)
 		return sdev->queue_depth;
 
@@ -1282,15 +1278,13 @@ int __ata_change_queue_depth(struct ata_port *ap, struct scsi_device *sdev,
 	if (sdev->queue_depth == queue_depth)
 		return -EINVAL;
 
-	scsi_adjust_queue_depth(sdev, queue_depth);
-	return queue_depth;
+	return scsi_change_queue_depth(sdev, queue_depth);
 }
 
 /**
  *	ata_scsi_change_queue_depth - SCSI callback for queue depth config
  *	@sdev: SCSI device to configure queue depth for
  *	@queue_depth: new queue depth
- *	@reason: calling context
  *
  *	This is libata standard hostt->change_queue_depth callback.
  *	SCSI will call into this callback when user tries to set queue
@@ -1302,12 +1296,11 @@ int __ata_change_queue_depth(struct ata_port *ap, struct scsi_device *sdev,
  *	RETURNS:
  *	Newly configured queue depth.
  */
-int ata_scsi_change_queue_depth(struct scsi_device *sdev, int queue_depth,
-				int reason)
+int ata_scsi_change_queue_depth(struct scsi_device *sdev, int queue_depth)
 {
 	struct ata_port *ap = ata_shost_to_port(sdev->host);
 
-	return __ata_change_queue_depth(ap, sdev, queue_depth, reason);
+	return __ata_change_queue_depth(ap, sdev, queue_depth);
 }
 
 /**
diff --git a/drivers/ata/sata_nv.c b/drivers/ata/sata_nv.c
index cdf99fac139a..1db6f5ce5e89 100644
--- a/drivers/ata/sata_nv.c
+++ b/drivers/ata/sata_nv.c
@@ -1951,7 +1951,7 @@ static int nv_swncq_slave_config(struct scsi_device *sdev)
 	ata_id_c_string(dev->id, model_num, ATA_ID_PROD, sizeof(model_num));
 
 	if (strncmp(model_num, "Maxtor", 6) == 0) {
-		ata_scsi_change_queue_depth(sdev, 1, SCSI_QDEPTH_DEFAULT);
+		ata_scsi_change_queue_depth(sdev, 1);
 		ata_dev_notice(dev, "Disabling SWNCQ mode (depth %x)\n",
 			       sdev->queue_depth);
 	}
diff --git a/drivers/infiniband/ulp/iser/iscsi_iser.c b/drivers/infiniband/ulp/iser/iscsi_iser.c
index 812a2891de58..20ca6a619476 100644
--- a/drivers/infiniband/ulp/iser/iscsi_iser.c
+++ b/drivers/infiniband/ulp/iser/iscsi_iser.c
@@ -911,7 +911,7 @@ static struct scsi_host_template iscsi_iser_sht = {
 	.module                 = THIS_MODULE,
 	.name                   = "iSCSI Initiator over iSER",
 	.queuecommand           = iscsi_queuecommand,
-	.change_queue_depth	= iscsi_change_queue_depth,
+	.change_queue_depth	= scsi_change_queue_depth,
 	.sg_tablesize           = ISCSI_ISER_SG_TABLESIZE,
 	.max_sectors		= 1024,
 	.cmd_per_lun            = ISER_DEF_CMD_PER_LUN,
diff --git a/drivers/infiniband/ulp/srp/ib_srp.c b/drivers/infiniband/ulp/srp/ib_srp.c
index 8d13a19e04b2..5461924c9f10 100644
--- a/drivers/infiniband/ulp/srp/ib_srp.c
+++ b/drivers/infiniband/ulp/srp/ib_srp.c
@@ -2402,18 +2402,15 @@ static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event)
  * srp_change_queue_depth - setting device queue depth
  * @sdev: scsi device struct
  * @qdepth: requested queue depth
- * @reason: SCSI_QDEPTH_DEFAULT
- * (see include/scsi/scsi_host.h for definition)
  *
  * Returns queue depth.
  */
 static int
-srp_change_queue_depth(struct scsi_device *sdev, int qdepth, int reason)
+srp_change_queue_depth(struct scsi_device *sdev, int qdepth)
 {
 	if (!sdev->tagged_supported)
 		qdepth = 1;
-	scsi_adjust_queue_depth(sdev, qdepth);
-	return sdev->queue_depth;
+	return scsi_change_queue_depth(sdev, qdepth);
 }
 
 static int srp_send_tsk_mgmt(struct srp_rdma_ch *ch, u64 req_tag,
diff --git a/drivers/message/fusion/mptscsih.c b/drivers/message/fusion/mptscsih.c
index dee06d6f0b68..6c9fc11efb87 100644
--- a/drivers/message/fusion/mptscsih.c
+++ b/drivers/message/fusion/mptscsih.c
@@ -2311,12 +2311,11 @@ mptscsih_slave_destroy(struct scsi_device *sdev)
  *	mptscsih_change_queue_depth - This function will set a devices queue depth
  *	@sdev: per scsi_device pointer
  *	@qdepth: requested queue depth
- *	@reason: calling context
  *
  *	Adding support for new 'change_queue_depth' api.
 */
 int
-mptscsih_change_queue_depth(struct scsi_device *sdev, int qdepth, int reason)
+mptscsih_change_queue_depth(struct scsi_device *sdev, int qdepth)
 {
 	MPT_SCSI_HOST		*hd = shost_priv(sdev->host);
 	VirtTarget 		*vtarget;
@@ -2327,9 +2326,6 @@ mptscsih_change_queue_depth(struct scsi_device *sdev, int qdepth, int reason)
 	starget = scsi_target(sdev);
 	vtarget = starget->hostdata;
 
-	if (reason != SCSI_QDEPTH_DEFAULT)
-		return -EOPNOTSUPP;
-
 	if (ioc->bus_type == SPI) {
 		if (!(vtarget->tflags & MPT_TARGET_FLAGS_Q_YES))
 			max_depth = 1;
@@ -2347,8 +2343,7 @@ mptscsih_change_queue_depth(struct scsi_device *sdev, int qdepth, int reason)
 	if (qdepth > max_depth)
 		qdepth = max_depth;
 
-	scsi_adjust_queue_depth(sdev, qdepth);
-	return sdev->queue_depth;
+	return scsi_change_queue_depth(sdev, qdepth);
 }
 
 /*
@@ -2392,8 +2387,7 @@ mptscsih_slave_configure(struct scsi_device *sdev)
 		    ioc->name, vtarget->negoFlags, vtarget->maxOffset,
 		    vtarget->minSyncFactor));
 
-	mptscsih_change_queue_depth(sdev, MPT_SCSI_CMD_PER_DEV_HIGH,
-				    SCSI_QDEPTH_DEFAULT);
+	mptscsih_change_queue_depth(sdev, MPT_SCSI_CMD_PER_DEV_HIGH);
 	dsprintk(ioc, printk(MYIOC_s_DEBUG_FMT
 		"tagged %d, simple %d\n",
 		ioc->name,sdev->tagged_supported, sdev->simple_tags));
diff --git a/drivers/message/fusion/mptscsih.h b/drivers/message/fusion/mptscsih.h
index e1b1a198a62a..2baeefd9be7a 100644
--- a/drivers/message/fusion/mptscsih.h
+++ b/drivers/message/fusion/mptscsih.h
@@ -128,8 +128,7 @@ extern int mptscsih_taskmgmt_complete(MPT_ADAPTER *ioc, MPT_FRAME_HDR *mf, MPT_F
 extern int mptscsih_scandv_complete(MPT_ADAPTER *ioc, MPT_FRAME_HDR *mf, MPT_FRAME_HDR *r);
 extern int mptscsih_event_process(MPT_ADAPTER *ioc, EventNotificationReply_t *pEvReply);
 extern int mptscsih_ioc_reset(MPT_ADAPTER *ioc, int post_reset);
-extern int mptscsih_change_queue_depth(struct scsi_device *sdev, int qdepth,
-				       int reason);
+extern int mptscsih_change_queue_depth(struct scsi_device *sdev, int qdepth);
 extern u8 mptscsih_raid_id_to_num(MPT_ADAPTER *ioc, u8 channel, u8 id);
 extern int mptscsih_is_phys_disk(MPT_ADAPTER *ioc, u8 channel, u8 id);
 extern struct device_attribute *mptscsih_host_attrs[];
diff --git a/drivers/s390/scsi/zfcp_scsi.c b/drivers/s390/scsi/zfcp_scsi.c
index 179bf3d8af6c..75f4bfc2b98a 100644
--- a/drivers/s390/scsi/zfcp_scsi.c
+++ b/drivers/s390/scsi/zfcp_scsi.c
@@ -32,13 +32,6 @@ static bool allow_lun_scan = 1;
 module_param(allow_lun_scan, bool, 0600);
 MODULE_PARM_DESC(allow_lun_scan, "For NPIV, scan and attach all storage LUNs");
 
-static int zfcp_scsi_change_queue_depth(struct scsi_device *sdev, int depth,
-					int reason)
-{
-	scsi_adjust_queue_depth(sdev, depth);
-	return sdev->queue_depth;
-}
-
 static void zfcp_scsi_slave_destroy(struct scsi_device *sdev)
 {
 	struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev);
@@ -54,7 +47,7 @@ static void zfcp_scsi_slave_destroy(struct scsi_device *sdev)
 static int zfcp_scsi_slave_configure(struct scsi_device *sdp)
 {
 	if (sdp->tagged_supported)
-		scsi_adjust_queue_depth(sdp, default_depth);
+		scsi_change_queue_depth(sdp, default_depth);
 	return 0;
 }
 
@@ -293,7 +286,7 @@ static struct scsi_host_template zfcp_scsi_host_template = {
 	.slave_alloc		 = zfcp_scsi_slave_alloc,
 	.slave_configure	 = zfcp_scsi_slave_configure,
 	.slave_destroy		 = zfcp_scsi_slave_destroy,
-	.change_queue_depth	 = zfcp_scsi_change_queue_depth,
+	.change_queue_depth	 = scsi_change_queue_depth,
 	.proc_name		 = "zfcp",
 	.can_queue		 = 4096,
 	.this_id		 = -1,
diff --git a/drivers/scsi/3w-9xxx.c b/drivers/scsi/3w-9xxx.c
index 1cf37032290a..cd4129ff7ae4 100644
--- a/drivers/scsi/3w-9xxx.c
+++ b/drivers/scsi/3w-9xxx.c
@@ -189,17 +189,6 @@ static ssize_t twa_show_stats(struct device *dev,
 	return len;
 } /* End twa_show_stats() */
 
-/* This function will set a devices queue depth */
-static int twa_change_queue_depth(struct scsi_device *sdev, int queue_depth,
-				  int reason)
-{
-	if (reason != SCSI_QDEPTH_DEFAULT)
-		return -EOPNOTSUPP;
-
-	scsi_adjust_queue_depth(sdev, queue_depth);
-	return queue_depth;
-} /* End twa_change_queue_depth() */
-
 /* Create sysfs 'stats' entry */
 static struct device_attribute twa_host_stats_attr = {
 	.attr = {
@@ -2014,7 +2003,7 @@ static struct scsi_host_template driver_template = {
 	.queuecommand		= twa_scsi_queue,
 	.eh_host_reset_handler	= twa_scsi_eh_reset,
 	.bios_param		= twa_scsi_biosparam,
-	.change_queue_depth	= twa_change_queue_depth,
+	.change_queue_depth	= scsi_change_queue_depth,
 	.can_queue		= TW_Q_LENGTH-2,
 	.slave_configure	= twa_slave_configure,
 	.this_id		= -1,
diff --git a/drivers/scsi/3w-sas.c b/drivers/scsi/3w-sas.c
index 547756b7d5bf..2361772d5909 100644
--- a/drivers/scsi/3w-sas.c
+++ b/drivers/scsi/3w-sas.c
@@ -191,17 +191,6 @@ static ssize_t twl_show_stats(struct device *dev,
 	return len;
 } /* End twl_show_stats() */
 
-/* This function will set a devices queue depth */
-static int twl_change_queue_depth(struct scsi_device *sdev, int queue_depth,
-				  int reason)
-{
-	if (reason != SCSI_QDEPTH_DEFAULT)
-		return -EOPNOTSUPP;
-
-	scsi_adjust_queue_depth(sdev, queue_depth);
-	return queue_depth;
-} /* End twl_change_queue_depth() */
-
 /* stats sysfs attribute initializer */
 static struct device_attribute twl_host_stats_attr = {
 	.attr = {
@@ -1588,7 +1577,7 @@ static struct scsi_host_template driver_template = {
 	.queuecommand		= twl_scsi_queue,
 	.eh_host_reset_handler	= twl_scsi_eh_reset,
 	.bios_param		= twl_scsi_biosparam,
-	.change_queue_depth	= twl_change_queue_depth,
+	.change_queue_depth	= scsi_change_queue_depth,
 	.can_queue		= TW_Q_LENGTH-2,
 	.slave_configure	= twl_slave_configure,
 	.this_id		= -1,
diff --git a/drivers/scsi/3w-xxxx.c b/drivers/scsi/3w-xxxx.c
index 261a4c1da962..c75f2048319f 100644
--- a/drivers/scsi/3w-xxxx.c
+++ b/drivers/scsi/3w-xxxx.c
@@ -523,17 +523,6 @@ static ssize_t tw_show_stats(struct device *dev, struct device_attribute *attr,
 	return len;
 } /* End tw_show_stats() */
 
-/* This function will set a devices queue depth */
-static int tw_change_queue_depth(struct scsi_device *sdev, int queue_depth,
-				 int reason)
-{
-	if (reason != SCSI_QDEPTH_DEFAULT)
-		return -EOPNOTSUPP;
-
-	scsi_adjust_queue_depth(sdev, queue_depth);
-	return queue_depth;
-} /* End tw_change_queue_depth() */
-
 /* Create sysfs 'stats' entry */
 static struct device_attribute tw_host_stats_attr = {
 	.attr = {
@@ -2268,7 +2257,7 @@ static struct scsi_host_template driver_template = {
 	.queuecommand		= tw_scsi_queue,
 	.eh_host_reset_handler	= tw_scsi_eh_reset,
 	.bios_param		= tw_scsi_biosparam,
-	.change_queue_depth	= tw_change_queue_depth,
+	.change_queue_depth	= scsi_change_queue_depth,
 	.can_queue		= TW_Q_LENGTH-2,
 	.slave_configure	= tw_slave_configure,
 	.this_id		= -1,
diff --git a/drivers/scsi/53c700.c b/drivers/scsi/53c700.c
index d7557b932113..aa915da2a5e5 100644
--- a/drivers/scsi/53c700.c
+++ b/drivers/scsi/53c700.c
@@ -175,7 +175,7 @@ STATIC void NCR_700_chip_reset(struct Scsi_Host *host);
 STATIC int NCR_700_slave_alloc(struct scsi_device *SDpnt);
 STATIC int NCR_700_slave_configure(struct scsi_device *SDpnt);
 STATIC void NCR_700_slave_destroy(struct scsi_device *SDpnt);
-static int NCR_700_change_queue_depth(struct scsi_device *SDpnt, int depth, int reason);
+static int NCR_700_change_queue_depth(struct scsi_device *SDpnt, int depth);
 static int NCR_700_change_queue_type(struct scsi_device *SDpnt, int depth);
 
 STATIC struct device_attribute *NCR_700_dev_attrs[];
@@ -904,7 +904,7 @@ process_message(struct Scsi_Host *host,	struct NCR_700_Host_Parameters *hostdata
 			hostdata->tag_negotiated &= ~(1<<scmd_id(SCp));
 
 			SCp->device->tagged_supported = 0;
-			scsi_adjust_queue_depth(SCp->device, host->cmd_per_lun);
+			scsi_change_queue_depth(SCp->device, host->cmd_per_lun);
 			scsi_set_tag_type(SCp->device, 0);
 		} else {
 			shost_printk(KERN_WARNING, host,
@@ -2052,7 +2052,7 @@ NCR_700_slave_configure(struct scsi_device *SDp)
 
 	/* to do here: allocate memory; build a queue_full list */
 	if(SDp->tagged_supported) {
-		scsi_adjust_queue_depth(SDp, NCR_700_DEFAULT_TAGS);
+		scsi_change_queue_depth(SDp, NCR_700_DEFAULT_TAGS);
 		NCR_700_set_tag_neg_state(SDp, NCR_700_START_TAG_NEGOTIATION);
 	}
 
@@ -2075,16 +2075,11 @@ NCR_700_slave_destroy(struct scsi_device *SDp)
 }
 
 static int
-N