dmaengine: idxd: remove interrupt disable for dev_lock

The spinlock is not being used in hard interrupt context. There is no need
to disable irq when acquiring the lock. The interrupt thread handler also
is not in bottom half context, therefore we can also remove disabling of
the bh. Convert all dev_lock acquisition to plain spin_lock() calls.

Reviewed-by: Dan Williams <[e-mail]>
Signed-off-by: Dave Jiang <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Vinod Koul <[e-mail]>

drivers/dma/idxd/cdev.c

···
 	struct idxd_user_context *ctx = filp->private_data;
 	struct idxd_wq *wq = ctx->wq;
 	struct idxd_device *idxd = wq->idxd;
-	unsigned long flags;
 	__poll_t out = 0;
 
 	poll_wait(filp, &wq->err_queue, wait);
-	spin_lock_irqsave(&idxd->dev_lock, flags);
+	spin_lock(&idxd->dev_lock);
 	if (idxd->sw_err.valid)
 		out = EPOLLIN | EPOLLRDNORM;
-	spin_unlock_irqrestore(&idxd->dev_lock, flags);
+	spin_unlock(&idxd->dev_lock);
 
 	return out;
 }

drivers/dma/idxd/device.c

···
 	int rc;
 	union wqcfg wqcfg;
 	unsigned int offset;
-	unsigned long flags;
 
 	rc = idxd_wq_disable(wq, false);
 	if (rc < 0)
 		return rc;
 
 	offset = WQCFG_OFFSET(idxd, wq->id, WQCFG_PASID_IDX);
-	spin_lock_irqsave(&idxd->dev_lock, flags);
+	spin_lock(&idxd->dev_lock);
 	wqcfg.bits[WQCFG_PASID_IDX] = ioread32(idxd->reg_base + offset);
 	wqcfg.pasid_en = 1;
 	wqcfg.pasid = pasid;
 	iowrite32(wqcfg.bits[WQCFG_PASID_IDX], idxd->reg_base + offset);
-	spin_unlock_irqrestore(&idxd->dev_lock, flags);
+	spin_unlock(&idxd->dev_lock);
 
 	rc = idxd_wq_enable(wq);
 	if (rc < 0)
···
 	int rc;
 	union wqcfg wqcfg;
 	unsigned int offset;
-	unsigned long flags;
 
 	rc = idxd_wq_disable(wq, false);
 	if (rc < 0)
 		return rc;
 
 	offset = WQCFG_OFFSET(idxd, wq->id, WQCFG_PASID_IDX);
-	spin_lock_irqsave(&idxd->dev_lock, flags);
+	spin_lock(&idxd->dev_lock);
 	wqcfg.bits[WQCFG_PASID_IDX] = ioread32(idxd->reg_base + offset);
 	wqcfg.pasid_en = 0;
 	wqcfg.pasid = 0;
 	iowrite32(wqcfg.bits[WQCFG_PASID_IDX], idxd->reg_base + offset);
-	spin_unlock_irqrestore(&idxd->dev_lock, flags);
+	spin_unlock(&idxd->dev_lock);
 
 	rc = idxd_wq_enable(wq);
 	if (rc < 0)
···
 {
 	struct device *dev = &idxd->pdev->dev;
 	u32 status;
-	unsigned long flags;
 
 	if (!idxd_is_enabled(idxd)) {
 		dev_dbg(dev, "Device is not enabled\n");
···
 		return -ENXIO;
 	}
 
-	spin_lock_irqsave(&idxd->dev_lock, flags);
+	spin_lock(&idxd->dev_lock);
 	idxd_device_clear_state(idxd);
 	idxd->state = IDXD_DEV_DISABLED;
-	spin_unlock_irqrestore(&idxd->dev_lock, flags);
+	spin_unlock(&idxd->dev_lock);
 	return 0;
 }
 
 void idxd_device_reset(struct idxd_device *idxd)
 {
-	unsigned long flags;
-
 	idxd_cmd_exec(idxd, IDXD_CMD_RESET_DEVICE, 0, NULL);
-	spin_lock_irqsave(&idxd->dev_lock, flags);
+	spin_lock(&idxd->dev_lock);
 	idxd_device_clear_state(idxd);
 	idxd->state = IDXD_DEV_DISABLED;
-	spin_unlock_irqrestore(&idxd->dev_lock, flags);
+	spin_unlock(&idxd->dev_lock);
 }
 
 void idxd_device_drain_pasid(struct idxd_device *idxd, int pasid)
···
 {
 	struct idxd_device *idxd = wq->idxd;
 	struct device *dev = &idxd->pdev->dev;
-	unsigned long flags;
 	int rc = -ENXIO;
 
 	lockdep_assert_held(&wq->wq_lock);
···
 	}
 
 	rc = 0;
-	spin_lock_irqsave(&idxd->dev_lock, flags);
+	spin_lock(&idxd->dev_lock);
 	if (test_bit(IDXD_FLAG_CONFIGURABLE, &idxd->flags))
 		rc = idxd_device_config(idxd);
-	spin_unlock_irqrestore(&idxd->dev_lock, flags);
+	spin_unlock(&idxd->dev_lock);
 	if (rc < 0) {
 		dev_dbg(dev, "Writing wq %d config failed: %d\n", wq->id, rc);
 		goto err;
···
 int idxd_device_drv_probe(struct idxd_dev *idxd_dev)
 {
 	struct idxd_device *idxd = idxd_dev_to_idxd(idxd_dev);
-	unsigned long flags;
 	int rc = 0;
 
 	/*
···
 	}
 
 	/* Device configuration */
-	spin_lock_irqsave(&idxd->dev_lock, flags);
+	spin_lock(&idxd->dev_lock);
 	if (test_bit(IDXD_FLAG_CONFIGURABLE, &idxd->flags))
 		rc = idxd_device_config(idxd);
-	spin_unlock_irqrestore(&idxd->dev_lock, flags);
+	spin_unlock(&idxd->dev_lock);
 	if (rc < 0)
 		return -ENXIO;
 

drivers/dma/idxd/irq.c

···
 	bool err = false;
 
 	if (cause & IDXD_INTC_ERR) {
-		spin_lock_bh(&idxd->dev_lock);
+		spin_lock(&idxd->dev_lock);
 		for (i = 0; i < 4; i++)
 			idxd->sw_err.bits[i] = ioread64(idxd->reg_base +
 					IDXD_SWERR_OFFSET + i * sizeof(u64));
···
 			}
 		}
 
-		spin_unlock_bh(&idxd->dev_lock);
+		spin_unlock(&idxd->dev_lock);
 		val |= IDXD_INTC_ERR;
 
 		for (i = 0; i < 4; i++)
···
 			INIT_WORK(&idxd->work, idxd_device_reinit);
 			queue_work(idxd->wq, &idxd->work);
 		} else {
-			spin_lock_bh(&idxd->dev_lock);
+			spin_lock(&idxd->dev_lock);
 			idxd_wqs_quiesce(idxd);
 			idxd_wqs_unmap_portal(idxd);
 			idxd_device_clear_state(idxd);
···
 				"idxd halted, need %s.\n",
 				gensts.reset_type == IDXD_DEVICE_RESET_FLR ?
 				"FLR" : "system reset");
-			spin_unlock_bh(&idxd->dev_lock);
+			spin_unlock(&idxd->dev_lock);
 			return -ENXIO;
 		}
 	}

drivers/dma/idxd/sysfs.c

···
 			    struct device_attribute *attr, char *buf)
 {
 	struct idxd_device *idxd = confdev_to_idxd(dev);
-	unsigned long flags;
 	int count = 0, i;
 
-	spin_lock_irqsave(&idxd->dev_lock, flags);
+	spin_lock(&idxd->dev_lock);
 	for (i = 0; i < idxd->max_wqs; i++) {
 		struct idxd_wq *wq = idxd->wqs[i];
 
 		count += wq->client_count;
 	}
-	spin_unlock_irqrestore(&idxd->dev_lock, flags);
+	spin_unlock(&idxd->dev_lock);
 
 	return sysfs_emit(buf, "%d\n", count);
 }
···
 {
 	struct idxd_device *idxd = confdev_to_idxd(dev);
 	int i, out = 0;
-	unsigned long flags;
 
-	spin_lock_irqsave(&idxd->dev_lock, flags);
+	spin_lock(&idxd->dev_lock);
 	for (i = 0; i < 4; i++)
 		out += sysfs_emit_at(buf, out, "%#018llx ", idxd->sw_err.bits[i]);
-	spin_unlock_irqrestore(&idxd->dev_lock, flags);
+	spin_unlock(&idxd->dev_lock);
 	out--;
 	out += sysfs_emit_at(buf, out, "\n");
 	return out;