isci: unify can_queue tracking on the tci_pool, uplevel tag assignment
The tci_pool tracks our outstanding command slots which are also the 'index'
portion of our tags. Grabbing the tag early in ->lldd_execute_task let's us
drop the isci_host_can_queue() and ->was_tag_assigned_by_user infrastructure.
->was_tag_assigned_by_user required the task context to be duplicated in
request-local buffer. With the tci established early we can build the
task_context directly into its final location and skip a memcpy.
With the task context buffer at a known address at request construction we
have the opportunity/obligation to also fix sgl handling. This rework feels
like it belongs in another patch but the sgl handling and task_context are too
intertwined.
1/ fix the 'ab' pair embedded in the task context to point to the 'cd' pair in
the task context (previously we were prematurely linking to the staging
buffer).
2/ fix the broken iteration of pio sgls that assumes all sgls are relative to
the request, and does a dangerous looking reverse lookup of physical
address to virtual address.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/drivers/scsi/isci/task.c b/drivers/scsi/isci/task.c
index 157e997..22f6fe1 100644
--- a/drivers/scsi/isci/task.c
+++ b/drivers/scsi/isci/task.c
@@ -63,6 +63,7 @@
#include "request.h"
#include "sata.h"
#include "task.h"
+#include "host.h"
/**
* isci_task_refuse() - complete the request to the upper layer driver in
@@ -156,25 +157,19 @@
{
struct isci_host *ihost = dev_to_ihost(task->dev);
struct isci_remote_device *idev;
- enum sci_status status;
unsigned long flags;
bool io_ready;
- int ret;
+ u16 tag;
dev_dbg(&ihost->pdev->dev, "%s: num=%d\n", __func__, num);
- /* Check if we have room for more tasks */
- ret = isci_host_can_queue(ihost, num);
-
- if (ret) {
- dev_warn(&ihost->pdev->dev, "%s: queue full\n", __func__);
- return ret;
- }
-
for_each_sas_task(num, task) {
+ enum sci_status status = SCI_FAILURE;
+
spin_lock_irqsave(&ihost->scic_lock, flags);
idev = isci_lookup_device(task->dev);
io_ready = isci_device_io_ready(idev, task);
+ tag = isci_alloc_tag(ihost);
spin_unlock_irqrestore(&ihost->scic_lock, flags);
dev_dbg(&ihost->pdev->dev,
@@ -185,15 +180,12 @@
if (!idev) {
isci_task_refuse(ihost, task, SAS_TASK_UNDELIVERED,
SAS_DEVICE_UNKNOWN);
- isci_host_can_dequeue(ihost, 1);
- } else if (!io_ready) {
-
+ } else if (!io_ready || tag == SCI_CONTROLLER_INVALID_IO_TAG) {
/* Indicate QUEUE_FULL so that the scsi midlayer
* retries.
*/
isci_task_refuse(ihost, task, SAS_TASK_COMPLETE,
SAS_QUEUE_FULL);
- isci_host_can_dequeue(ihost, 1);
} else {
/* There is a device and it's ready for I/O. */
spin_lock_irqsave(&task->task_state_lock, flags);
@@ -206,13 +198,12 @@
isci_task_refuse(ihost, task,
SAS_TASK_UNDELIVERED,
SAM_STAT_TASK_ABORTED);
- isci_host_can_dequeue(ihost, 1);
} else {
task->task_state_flags |= SAS_TASK_AT_INITIATOR;
spin_unlock_irqrestore(&task->task_state_lock, flags);
/* build and send the request. */
- status = isci_request_execute(ihost, idev, task, gfp_flags);
+ status = isci_request_execute(ihost, idev, task, tag, gfp_flags);
if (status != SCI_SUCCESS) {
@@ -231,10 +222,17 @@
isci_task_refuse(ihost, task,
SAS_TASK_COMPLETE,
SAS_QUEUE_FULL);
- isci_host_can_dequeue(ihost, 1);
}
}
}
+ if (status != SCI_SUCCESS && tag != SCI_CONTROLLER_INVALID_IO_TAG) {
+ spin_lock_irqsave(&ihost->scic_lock, flags);
+ /* command never hit the device, so just free
+ * the tci and skip the sequence increment
+ */
+ isci_tci_free(ihost, ISCI_TAG_TCI(tag));
+ spin_unlock_irqrestore(&ihost->scic_lock, flags);
+ }
isci_put_device(idev);
}
return 0;
@@ -242,7 +240,7 @@
static struct isci_request *isci_task_request_build(struct isci_host *ihost,
struct isci_remote_device *idev,
- struct isci_tmf *isci_tmf)
+ u16 tag, struct isci_tmf *isci_tmf)
{
enum sci_status status = SCI_FAILURE;
struct isci_request *ireq = NULL;
@@ -259,8 +257,7 @@
return NULL;
/* let the core do it's construct. */
- status = scic_task_request_construct(&ihost->sci, &idev->sci,
- SCI_CONTROLLER_INVALID_IO_TAG,
+ status = scic_task_request_construct(&ihost->sci, &idev->sci, tag,
&ireq->sci);
if (status != SCI_SUCCESS) {
@@ -290,8 +287,7 @@
return ireq;
errout:
isci_request_free(ihost, ireq);
- ireq = NULL;
- return ireq;
+ return NULL;
}
int isci_task_execute_tmf(struct isci_host *ihost,
@@ -305,6 +301,14 @@
int ret = TMF_RESP_FUNC_FAILED;
unsigned long flags;
unsigned long timeleft;
+ u16 tag;
+
+ spin_lock_irqsave(&ihost->scic_lock, flags);
+ tag = isci_alloc_tag(ihost);
+ spin_unlock_irqrestore(&ihost->scic_lock, flags);
+
+ if (tag == SCI_CONTROLLER_INVALID_IO_TAG)
+ return ret;
/* sanity check, return TMF_RESP_FUNC_FAILED
* if the device is not there and ready.
@@ -316,7 +320,7 @@
"%s: isci_device = %p not ready (%#lx)\n",
__func__,
isci_device, isci_device ? isci_device->flags : 0);
- return TMF_RESP_FUNC_FAILED;
+ goto err_tci;
} else
dev_dbg(&ihost->pdev->dev,
"%s: isci_device = %p\n",
@@ -327,22 +331,16 @@
/* Assign the pointer to the TMF's completion kernel wait structure. */
tmf->complete = &completion;
- ireq = isci_task_request_build(ihost, isci_device, tmf);
- if (!ireq) {
- dev_warn(&ihost->pdev->dev,
- "%s: isci_task_request_build failed\n",
- __func__);
- return TMF_RESP_FUNC_FAILED;
- }
+ ireq = isci_task_request_build(ihost, isci_device, tag, tmf);
+ if (!ireq)
+ goto err_tci;
spin_lock_irqsave(&ihost->scic_lock, flags);
/* start the TMF io. */
- status = scic_controller_start_task(
- &ihost->sci,
- sci_device,
- &ireq->sci,
- SCI_CONTROLLER_INVALID_IO_TAG);
+ status = scic_controller_start_task(&ihost->sci,
+ sci_device,
+ &ireq->sci);
if (status != SCI_TASK_SUCCESS) {
dev_warn(&ihost->pdev->dev,
@@ -351,8 +349,7 @@
status,
ireq);
spin_unlock_irqrestore(&ihost->scic_lock, flags);
- isci_request_free(ihost, ireq);
- return ret;
+ goto err_ireq;
}
if (tmf->cb_state_func != NULL)
@@ -403,6 +400,15 @@
ireq);
return ret;
+
+ err_ireq:
+ isci_request_free(ihost, ireq);
+ err_tci:
+ spin_lock_irqsave(&ihost->scic_lock, flags);
+ isci_tci_free(ihost, ISCI_TAG_TCI(tag));
+ spin_unlock_irqrestore(&ihost->scic_lock, flags);
+
+ return ret;
}
void isci_task_build_tmf(