isci: implement I_T_nexus_reset
This is a requirement for 2.6.39's new libata eh.
Still some questions about lldd_dev_gone racing against dev->lldd_dev
lookups, but we are at least no more broken than mvsas in this regard.
We also short-circuit I_T_nexus_reset invocations from the device
discovery path (IDEV_EH similar to MVS_DEV_EH) to filter out the
resulting domain rediscoveries triggered by the reset.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/drivers/scsi/isci/remote_device.c b/drivers/scsi/isci/remote_device.c
index 15c1e6c..ee6fe1d 100644
--- a/drivers/scsi/isci/remote_device.c
+++ b/drivers/scsi/isci/remote_device.c
@@ -891,6 +891,7 @@
clear_bit(IDEV_START_PENDING, &idev->flags);
clear_bit(IDEV_STOP_PENDING, &idev->flags);
+ clear_bit(IDEV_EH, &idev->flags);
wake_up(&ihost->eventq);
}
diff --git a/drivers/scsi/isci/remote_device.h b/drivers/scsi/isci/remote_device.h
index c7db499..2e433b7 100644
--- a/drivers/scsi/isci/remote_device.h
+++ b/drivers/scsi/isci/remote_device.h
@@ -134,6 +134,7 @@
#define IDEV_START_PENDING 0
#define IDEV_STOP_PENDING 1
#define IDEV_ALLOCATED 2
+ #define IDEV_EH 3
unsigned long flags;
struct isci_port *isci_port;
struct domain_device *domain_dev;
diff --git a/drivers/scsi/isci/task.c b/drivers/scsi/isci/task.c
index 8449d8a..3a3f546 100644
--- a/drivers/scsi/isci/task.c
+++ b/drivers/scsi/isci/task.c
@@ -1022,9 +1022,11 @@
"%s: domain_device=%p, isci_host=%p; isci_device=%p\n",
__func__, domain_device, isci_host, isci_device);
- if (isci_device != NULL)
+ if (isci_device != NULL) {
device_stopping = (isci_device->status == isci_stopping)
|| (isci_device->status == isci_stopped);
+ set_bit(IDEV_EH, &isci_device->flags);
+ }
/* If there is a device reset pending on any request in the
* device's list, fail this LUN reset request in order to
@@ -1069,12 +1071,6 @@
return TMF_RESP_FUNC_FAILED;
}
-int isci_task_I_T_nexus_reset(struct domain_device *dev)
-{
- return TMF_RESP_FUNC_FAILED;
-}
-
-
/* Task Management Functions. Must be called from process context. */
/**
@@ -1171,6 +1167,12 @@
device_stopping = (isci_device->status == isci_stopping)
|| (isci_device->status == isci_stopped);
+ /* XXX need to fix device lookup lifetime (needs to be done
+ * under scic_lock, among other things...), but for now assume
+ * the device is available like the above code
+ */
+ set_bit(IDEV_EH, &isci_device->flags);
+
/* This version of the driver will fail abort requests for
* SATA/STP. Failing the abort request this way will cause the
* SCSI error handler thread to escalate to LUN reset
@@ -1481,86 +1483,94 @@
complete(tmf_complete);
}
-/**
- * isci_bus_reset_handler() - This function performs a target reset of the
- * device referenced by "cmd'. This function is exported through the
- * "struct scsi_host_template" structure such that it is called when an I/O
- * recovery process has escalated to a target reset. Note that this function
- * is called from the scsi error handler event thread, so may block on calls.
- * @scsi_cmd: This parameter specifies the target to be reset.
- *
- * SUCCESS if the reset process was successful, else FAILED.
- */
-int isci_bus_reset_handler(struct scsi_cmnd *cmd)
+static int isci_reset_device(struct domain_device *dev, int hard_reset)
{
- struct domain_device *dev = cmd_to_domain_dev(cmd);
- struct isci_host *isci_host = dev_to_ihost(dev);
- unsigned long flags = 0;
+ struct isci_remote_device *idev = dev->lldd_dev;
+ struct sas_phy *phy = sas_find_local_phy(dev);
+ struct isci_host *ihost = dev_to_ihost(dev);
enum sci_status status;
- int base_status;
- struct isci_remote_device *isci_dev = dev->lldd_dev;
+ unsigned long flags;
+ int rc;
- dev_dbg(&isci_host->pdev->dev,
- "%s: cmd %p, isci_dev %p\n",
- __func__, cmd, isci_dev);
+ dev_dbg(&ihost->pdev->dev, "%s: idev %p\n", __func__, idev);
- if (!isci_dev) {
- dev_warn(&isci_host->pdev->dev,
- "%s: isci_dev is GONE!\n",
+ if (!idev) {
+ dev_warn(&ihost->pdev->dev,
+ "%s: idev is GONE!\n",
__func__);
return TMF_RESP_FUNC_COMPLETE; /* Nothing to reset. */
}
- spin_lock_irqsave(&isci_host->scic_lock, flags);
- status = scic_remote_device_reset(&isci_dev->sci);
+ spin_lock_irqsave(&ihost->scic_lock, flags);
+ status = scic_remote_device_reset(&idev->sci);
if (status != SCI_SUCCESS) {
- spin_unlock_irqrestore(&isci_host->scic_lock, flags);
+ spin_unlock_irqrestore(&ihost->scic_lock, flags);
- scmd_printk(KERN_WARNING, cmd,
- "%s: scic_remote_device_reset(%p) returned %d!\n",
- __func__, isci_dev, status);
+ dev_warn(&ihost->pdev->dev,
+ "%s: scic_remote_device_reset(%p) returned %d!\n",
+ __func__, idev, status);
return TMF_RESP_FUNC_FAILED;
}
- spin_unlock_irqrestore(&isci_host->scic_lock, flags);
+ spin_unlock_irqrestore(&ihost->scic_lock, flags);
/* Make sure all pending requests are able to be fully terminated. */
- isci_device_clear_reset_pending(isci_host, isci_dev);
+ isci_device_clear_reset_pending(ihost, idev);
+
+ rc = sas_phy_reset(phy, hard_reset);
+ msleep(2000); /* just like mvsas */
/* Terminate in-progress I/O now. */
- isci_remote_device_nuke_requests(isci_host, isci_dev);
+ isci_remote_device_nuke_requests(ihost, idev);
- /* Call into the libsas default handler (which calls sas_phy_reset). */
- base_status = sas_eh_bus_reset_handler(cmd);
-
- if (base_status != SUCCESS) {
-
- /* There can be cases where the resets to individual devices
- * behind an expander will fail because of an unplug of the
- * expander itself.
- */
- scmd_printk(KERN_WARNING, cmd,
- "%s: sas_eh_bus_reset_handler(%p) returned %d!\n",
- __func__, cmd, base_status);
- }
-
- /* WHAT TO DO HERE IF sas_phy_reset FAILS? */
- spin_lock_irqsave(&isci_host->scic_lock, flags);
- status = scic_remote_device_reset_complete(&isci_dev->sci);
- spin_unlock_irqrestore(&isci_host->scic_lock, flags);
+ spin_lock_irqsave(&ihost->scic_lock, flags);
+ status = scic_remote_device_reset_complete(&idev->sci);
+ spin_unlock_irqrestore(&ihost->scic_lock, flags);
if (status != SCI_SUCCESS) {
- scmd_printk(KERN_WARNING, cmd,
- "%s: scic_remote_device_reset_complete(%p) "
- "returned %d!\n",
- __func__, isci_dev, status);
+ dev_warn(&ihost->pdev->dev,
+ "%s: scic_remote_device_reset_complete(%p) "
+ "returned %d!\n", __func__, idev, status);
}
- /* WHAT TO DO HERE IF scic_remote_device_reset_complete FAILS? */
- dev_dbg(&isci_host->pdev->dev,
- "%s: cmd %p, isci_dev %p complete.\n",
- __func__, cmd, isci_dev);
+ dev_dbg(&ihost->pdev->dev, "%s: idev %p complete.\n", __func__, idev);
- return TMF_RESP_FUNC_COMPLETE;
+ return rc;
+}
+
+int isci_task_I_T_nexus_reset(struct domain_device *dev)
+{
+ struct isci_host *ihost = dev_to_ihost(dev);
+ int ret = TMF_RESP_FUNC_FAILED, hard_reset = 1;
+ struct isci_remote_device *idev;
+ unsigned long flags;
+
+ /* XXX mvsas is not protecting against ->lldd_dev_gone(), are we
+ * being too paranoid, or is mvsas busted?!
+ */
+ spin_lock_irqsave(&ihost->scic_lock, flags);
+ idev = dev->lldd_dev;
+ if (!idev || !test_bit(IDEV_EH, &idev->flags))
+ ret = TMF_RESP_FUNC_COMPLETE;
+ spin_unlock_irqrestore(&ihost->scic_lock, flags);
+
+ if (ret == TMF_RESP_FUNC_COMPLETE)
+ return ret;
+
+ if (dev->dev_type == SATA_DEV || (dev->tproto & SAS_PROTOCOL_STP))
+ hard_reset = 0;
+
+ return isci_reset_device(dev, hard_reset);
+}
+
+int isci_bus_reset_handler(struct scsi_cmnd *cmd)
+{
+ struct domain_device *dev = sdev_to_domain_dev(cmd->device);
+ int hard_reset = 1;
+
+ if (dev->dev_type == SATA_DEV || (dev->tproto & SAS_PROTOCOL_STP))
+ hard_reset = 0;
+
+ return isci_reset_device(dev, hard_reset);
}