uas: Don't allow more then one task to run at the same time

Since we use a fixed tag / stream for tasks we cannot allow more then one
to run at the same time. This could happen before this time if a task timed
out.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
This commit is contained in:
Hans de Goede 2013-10-29 10:51:00 +01:00 committed by Sarah Sharp
parent 70cf0fba76
commit b83b86a352

View File

@ -53,6 +53,7 @@ struct uas_dev_info {
unsigned cmd_pipe, status_pipe, data_in_pipe, data_out_pipe;
unsigned use_streams:1;
unsigned uas_sense_old:1;
unsigned running_task:1;
struct scsi_cmnd *cmnd;
spinlock_t lock;
struct work_struct work;
@ -195,6 +196,7 @@ static void uas_zap_dead(struct uas_dev_info *devinfo)
DATA_OUT_URB_INFLIGHT);
uas_try_complete(cmnd, __func__);
}
devinfo->running_task = 0;
spin_unlock_irqrestore(&devinfo->lock, flags);
}
@ -340,6 +342,9 @@ static void uas_stat_cmplt(struct urb *urb)
if (!cmnd) {
if (iu->iu_id == IU_ID_RESPONSE) {
if (!devinfo->running_task)
dev_warn(&urb->dev->dev,
"stat urb: recv unexpected response iu\n");
/* store results for uas_eh_task_mgmt() */
memcpy(&devinfo->response, iu, sizeof(devinfo->response));
}
@ -726,14 +731,26 @@ static int uas_eh_task_mgmt(struct scsi_cmnd *cmnd,
u16 tag = devinfo->qdepth;
unsigned long flags;
struct urb *sense_urb;
int result = SUCCESS;
spin_lock_irqsave(&devinfo->lock, flags);
if (devinfo->running_task) {
shost_printk(KERN_INFO, shost,
"%s: %s: error already running a task\n",
__func__, fname);
spin_unlock_irqrestore(&devinfo->lock, flags);
return FAILED;
}
devinfo->running_task = 1;
memset(&devinfo->response, 0, sizeof(devinfo->response));
sense_urb = uas_submit_sense_urb(shost, GFP_ATOMIC, tag);
if (!sense_urb) {
shost_printk(KERN_INFO, shost,
"%s: %s: submit sense urb failed\n",
__func__, fname);
devinfo->running_task = 0;
spin_unlock_irqrestore(&devinfo->lock, flags);
return FAILED;
}
@ -741,6 +758,7 @@ static int uas_eh_task_mgmt(struct scsi_cmnd *cmnd,
shost_printk(KERN_INFO, shost,
"%s: %s: submit task mgmt urb failed\n",
__func__, fname);
devinfo->running_task = 0;
spin_unlock_irqrestore(&devinfo->lock, flags);
usb_kill_urb(sense_urb);
return FAILED;
@ -748,23 +766,33 @@ static int uas_eh_task_mgmt(struct scsi_cmnd *cmnd,
spin_unlock_irqrestore(&devinfo->lock, flags);
if (usb_wait_anchor_empty_timeout(&devinfo->sense_urbs, 3000) == 0) {
/*
* Note we deliberately do not clear running_task here. If we
* allow new tasks to be submitted, there is no way to figure
* out if a received response_iu is for the failed task or for
* the new one. A bus-reset will eventually clear running_task.
*/
shost_printk(KERN_INFO, shost,
"%s: %s timed out\n", __func__, fname);
return FAILED;
}
spin_lock_irqsave(&devinfo->lock, flags);
devinfo->running_task = 0;
if (be16_to_cpu(devinfo->response.tag) != tag) {
shost_printk(KERN_INFO, shost,
"%s: %s failed (wrong tag %d/%d)\n", __func__,
fname, be16_to_cpu(devinfo->response.tag), tag);
return FAILED;
}
if (devinfo->response.response_code != RC_TMF_COMPLETE) {
result = FAILED;
} else if (devinfo->response.response_code != RC_TMF_COMPLETE) {
shost_printk(KERN_INFO, shost,
"%s: %s failed (rc 0x%x)\n", __func__,
fname, devinfo->response.response_code);
return FAILED;
result = FAILED;
}
return SUCCESS;
spin_unlock_irqrestore(&devinfo->lock, flags);
return result;
}
static int uas_eh_abort_handler(struct scsi_cmnd *cmnd)
@ -982,6 +1010,7 @@ static int uas_probe(struct usb_interface *intf, const struct usb_device_id *id)
devinfo->intf = intf;
devinfo->udev = udev;
devinfo->resetting = 0;
devinfo->running_task = 0;
init_usb_anchor(&devinfo->cmd_urbs);
init_usb_anchor(&devinfo->sense_urbs);
init_usb_anchor(&devinfo->data_urbs);