scsi: aacraid: use scsi_host_busy_iter() in get_num_of_incomplete_fibs()

Use the SCSI midlayer helper to traverse the number of outstanding
commands. This also eliminates the last usage for the cmd_list
functionality so we can drop it.

Link: https://lore.kernel.org/r/20200228075318.91255-13-hare@suse.de
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Balsundar P <balsundar.p@microchip.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/aacraid/linit.c

@@ -622,54 +622,56 @@ static int aac_ioctl(struct scsi_device *sdev, unsigned int cmd,
 	return aac_do_ioctl(dev, cmd, arg);
 }
 
-static int get_num_of_incomplete_fibs(struct aac_dev *aac)
+struct fib_count_data {
+	int mlcnt;
+	int llcnt;
+	int ehcnt;
+	int fwcnt;
+	int krlcnt;
+};
+
+static bool fib_count_iter(struct scsi_cmnd *scmnd, void *data, bool reserved)
 {
+	struct fib_count_data *fib_count = data;
+
+	switch (scmnd->SCp.phase) {
+	case AAC_OWNER_FIRMWARE:
+		fib_count->fwcnt++;
+		break;
+	case AAC_OWNER_ERROR_HANDLER:
+		fib_count->ehcnt++;
+		break;
+	case AAC_OWNER_LOWLEVEL:
+		fib_count->llcnt++;
+		break;
+	case AAC_OWNER_MIDLEVEL:
+		fib_count->mlcnt++;
+		break;
+	default:
+		fib_count->krlcnt++;
+		break;
+	}
+	return true;
+}
 
-	unsigned long flags;
-	struct scsi_device *sdev = NULL;
+/* Called during SCSI EH, so we don't need to block requests */
+static int get_num_of_incomplete_fibs(struct aac_dev *aac)
+{
 	struct Scsi_Host *shost = aac->scsi_host_ptr;
-	struct scsi_cmnd *scmnd = NULL;
 	struct device *ctrl_dev;
+	struct fib_count_data fcnt = { };
 
-	int mlcnt  = 0;
-	int llcnt  = 0;
-	int ehcnt  = 0;
-	int fwcnt  = 0;
-	int krlcnt = 0;
-
-	__shost_for_each_device(sdev, shost) {
-		spin_lock_irqsave(&sdev->list_lock, flags);
-		list_for_each_entry(scmnd, &sdev->cmd_list, list) {
-			switch (scmnd->SCp.phase) {
-			case AAC_OWNER_FIRMWARE:
-				fwcnt++;
-				break;
-			case AAC_OWNER_ERROR_HANDLER:
-				ehcnt++;
-				break;
-			case AAC_OWNER_LOWLEVEL:
-				llcnt++;
-				break;
-			case AAC_OWNER_MIDLEVEL:
-				mlcnt++;
-				break;
-			default:
-				krlcnt++;
-				break;
-			}
-		}
-		spin_unlock_irqrestore(&sdev->list_lock, flags);
-	}
+	scsi_host_busy_iter(shost, fib_count_iter, &fcnt);
 
 	ctrl_dev = &aac->pdev->dev;
 
-	dev_info(ctrl_dev, "outstanding cmd: midlevel-%d\n", mlcnt);
-	dev_info(ctrl_dev, "outstanding cmd: lowlevel-%d\n", llcnt);
-	dev_info(ctrl_dev, "outstanding cmd: error handler-%d\n", ehcnt);
-	dev_info(ctrl_dev, "outstanding cmd: firmware-%d\n", fwcnt);
-	dev_info(ctrl_dev, "outstanding cmd: kernel-%d\n", krlcnt);
+	dev_info(ctrl_dev, "outstanding cmd: midlevel-%d\n", fcnt.mlcnt);
+	dev_info(ctrl_dev, "outstanding cmd: lowlevel-%d\n", fcnt.llcnt);
+	dev_info(ctrl_dev, "outstanding cmd: error handler-%d\n", fcnt.ehcnt);
+	dev_info(ctrl_dev, "outstanding cmd: firmware-%d\n", fcnt.fwcnt);
+	dev_info(ctrl_dev, "outstanding cmd: kernel-%d\n", fcnt.krlcnt);
 
-	return mlcnt + llcnt + ehcnt + fwcnt;
+	return fcnt.mlcnt + fcnt.llcnt + fcnt.ehcnt + fcnt.fwcnt;
 }
 
 static int aac_eh_abort(struct scsi_cmnd* cmd)
@@ -1675,7 +1677,6 @@ static int aac_probe_one(struct pci_dev *pdev, const struct pci_device_id *id)
 	shost->irq = pdev->irq;
 	shost->unique_id = unique_id;
 	shost->max_cmd_len = 16;
-	shost->use_cmd_list = 1;
 
 	if (aac_cfg_major == AAC_CHARDEV_NEEDS_REINIT)
 		aac_init_char();