scsi: add new scsi-command flag for tagged commands
Currently scsi piggy backs on the block layer to define the concept
of a tagged command. But we want to be able to have block-level host-wide
tags assigned even for untagged commands like the initial INQUIRY, so add
a new SCSI-level flag for commands that are tagged at the scsi level, so
that even commands without that set can have tags assigned to them. Note
that this alredy is the case for the blk-mq code path, and this just lets
the old path catch up with it.
We also set this flag based upon sdev->simple_tags instead of the block
queue flag, so that it is entirely independent of the block layer tagging,
and thus always correct even if a driver doesn't use block level tagging
yet.
Also remove the old blk_rq_tagged; it was only used by SCSI drivers, and
removing it forces them to look for the proper replacement.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
diff --git a/Documentation/block/biodoc.txt b/Documentation/block/biodoc.txt
index 2101e71..6b972b2 100644
--- a/Documentation/block/biodoc.txt
+++ b/Documentation/block/biodoc.txt
@@ -827,10 +827,6 @@
that requests are restarted in the order they were queue. This may happen
if the driver needs to use blk_queue_invalidate_tags().
-Tagging also defines a new request flag, REQ_QUEUED. This is set whenever
-a request is currently tagged. You should not use this flag directly,
-blk_rq_tagged(rq) is the portable way to do so.
-
3.3 I/O Submission
The routine submit_bio() is used to submit a single io. Higher level i/o
diff --git a/block/blk-core.c b/block/blk-core.c
index 0421b53..2e7424b 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -1266,7 +1266,7 @@
blk_clear_rq_complete(rq);
trace_block_rq_requeue(q, rq);
- if (blk_rq_tagged(rq))
+ if (rq->cmd_flags & REQ_QUEUED)
blk_queue_end_tag(q, rq);
BUG_ON(blk_queued_rq(rq));
@@ -2554,7 +2554,7 @@
*/
void blk_finish_request(struct request *req, int error)
{
- if (blk_rq_tagged(req))
+ if (req->cmd_flags & REQ_QUEUED)
blk_queue_end_tag(req->q, req);
BUG_ON(blk_queued_rq(req));
diff --git a/drivers/scsi/53c700.c b/drivers/scsi/53c700.c
index 474cc6d..5143d32 100644
--- a/drivers/scsi/53c700.c
+++ b/drivers/scsi/53c700.c
@@ -1767,7 +1767,7 @@
*/
if(NCR_700_get_depth(SCp->device) != 0
&& (!(hostdata->tag_negotiated & (1<<scmd_id(SCp)))
- || !blk_rq_tagged(SCp->request))) {
+ || !(SCp->flags & SCMD_TAGGED))) {
CDEBUG(KERN_ERR, SCp, "has non zero depth %d\n",
NCR_700_get_depth(SCp->device));
return SCSI_MLQUEUE_DEVICE_BUSY;
@@ -1795,7 +1795,7 @@
printk("53c700: scsi%d, command ", SCp->device->host->host_no);
scsi_print_command(SCp);
#endif
- if(blk_rq_tagged(SCp->request)
+ if ((SCp->flags & SCMD_TAGGED)
&& (hostdata->tag_negotiated &(1<<scmd_id(SCp))) == 0
&& NCR_700_get_tag_neg_state(SCp->device) == NCR_700_START_TAG_NEGOTIATION) {
scmd_printk(KERN_ERR, SCp, "Enabling Tag Command Queuing\n");
@@ -1809,7 +1809,7 @@
*
* FIXME: This will royally screw up on multiple LUN devices
* */
- if(!blk_rq_tagged(SCp->request)
+ if (!(SCp->flags & SCMD_TAGGED)
&& (hostdata->tag_negotiated &(1<<scmd_id(SCp)))) {
scmd_printk(KERN_INFO, SCp, "Disabling Tag Command Queuing\n");
hostdata->tag_negotiated &= ~(1<<scmd_id(SCp));
diff --git a/drivers/scsi/aic7xxx/aic7xxx_osm.c b/drivers/scsi/aic7xxx/aic7xxx_osm.c
index d2c9bf3..63bae7c 100644
--- a/drivers/scsi/aic7xxx/aic7xxx_osm.c
+++ b/drivers/scsi/aic7xxx/aic7xxx_osm.c
@@ -1447,7 +1447,7 @@
* we are storing a full busy target *lun*
* table in SCB space.
*/
- if (!blk_rq_tagged(cmd->request)
+ if (!(cmd->flags & SCMD_TAGGED)
&& (ahc->features & AHC_SCB_BTT) == 0) {
int target_offset;
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 38f8c85..994eb08 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -1740,7 +1740,7 @@
* we add the dev to the starved list so it eventually gets
* a run when a tag is freed.
*/
- if (blk_queue_tagged(q) && !blk_rq_tagged(req)) {
+ if (blk_queue_tagged(q) && !(req->cmd_flags & REQ_QUEUED)) {
spin_lock_irq(shost->host_lock);
if (list_empty(&sdev->starved_entry))
list_add_tail(&sdev->starved_entry,
@@ -1754,6 +1754,11 @@
if (!scsi_host_queue_ready(q, shost, sdev))
goto host_not_ready;
+
+ if (sdev->simple_tags)
+ cmd->flags |= SCMD_TAGGED;
+ else
+ cmd->flags &= ~SCMD_TAGGED;
/*
* Finally, initialize any error handling parameters, and set up
@@ -1908,10 +1913,10 @@
blk_mq_start_request(req);
}
- if (blk_queue_tagged(q))
- req->cmd_flags |= REQ_QUEUED;
+ if (sdev->simple_tags)
+ cmd->flags |= SCMD_TAGGED;
else
- req->cmd_flags &= ~REQ_QUEUED;
+ cmd->flags &= ~SCMD_TAGGED;
scsi_init_cmd_errh(cmd);
cmd->scsi_done = scsi_mq_done;
diff --git a/drivers/usb/storage/uas.c b/drivers/usb/storage/uas.c
index 89b2434..b38bc13 100644
--- a/drivers/usb/storage/uas.c
+++ b/drivers/usb/storage/uas.c
@@ -181,7 +181,7 @@
{
int tag;
- if (blk_rq_tagged(cmnd->request))
+ if (cmnd->flags & SCMD_TAGGED)
tag = cmnd->request->tag + 2;
else
tag = 1;
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index aac0f9e..6d76b8b 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1136,7 +1136,6 @@
/*
* tag stuff
*/
-#define blk_rq_tagged(rq) ((rq)->cmd_flags & REQ_QUEUED)
extern int blk_queue_start_tag(struct request_queue *, struct request *);
extern struct request *blk_queue_find_tag(struct request_queue *, int);
extern void blk_queue_end_tag(struct request_queue *, struct request *);
diff --git a/include/scsi/scsi_cmnd.h b/include/scsi/scsi_cmnd.h
index 522a5f27..e119142 100644
--- a/include/scsi/scsi_cmnd.h
+++ b/include/scsi/scsi_cmnd.h
@@ -53,6 +53,9 @@
volatile int phase;
};
+/* for scmd->flags */
+#define SCMD_TAGGED (1 << 0)
+
struct scsi_cmnd {
struct scsi_device *device;
struct list_head list; /* scsi_cmnd participates in queue lists */
@@ -132,6 +135,7 @@
* to be at an address < 16Mb). */
int result; /* Status code from lower level driver */
+ int flags; /* Command flags */
unsigned char tag; /* SCSI-II queued command tag */
};
diff --git a/include/scsi/scsi_tcq.h b/include/scsi/scsi_tcq.h
index 1712dab..032df74 100644
--- a/include/scsi/scsi_tcq.h
+++ b/include/scsi/scsi_tcq.h
@@ -101,11 +101,9 @@
**/
static inline int scsi_populate_tag_msg(struct scsi_cmnd *cmd, char *msg)
{
- struct request *req = cmd->request;
-
- if (blk_rq_tagged(req)) {
+ if (cmd->flags & SCMD_TAGGED) {
*msg++ = MSG_SIMPLE_TAG;
- *msg++ = req->tag;
+ *msg++ = cmd->request->tag;
return 2;
}