[PATCH 10/12] nvme-pci: split nvme_dbbuf_dma_alloc

[Christoph Hellwig]

Move the clearing of the already allocated doorbell buffer memory to
the caller, and instead move printing the error for the allocation
failure into the helper.

Signed-off-by: Christoph Hellwig <hch at lst.de>
---
 drivers/nvme/host/pci.c | 45 +++++++++++++++++++----------------------
 1 file changed, 21 insertions(+), 24 deletions(-)

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index 64e2bd2d4f61e..1b3c96a4b7c90 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -239,36 +239,28 @@ static inline unsigned int nvme_dbbuf_size(struct nvme_dev *dev)
 	return dev->nr_allocated_queues * 8 * dev->db_stride;
 }
 
-static int nvme_dbbuf_dma_alloc(struct nvme_dev *dev)
+static void nvme_dbbuf_dma_alloc(struct nvme_dev *dev)
 {
 	unsigned int mem_size = nvme_dbbuf_size(dev);
 
-	if (dev->dbbuf_dbs) {
-		/*
-		 * Clear the dbbuf memory so the driver doesn't observe stale
-		 * values from the previous instantiation.
-		 */
-		memset(dev->dbbuf_dbs, 0, mem_size);
-		memset(dev->dbbuf_eis, 0, mem_size);
-		return 0;
-	}
-
 	dev->dbbuf_dbs = dma_alloc_coherent(dev->dev, mem_size,
 					    &dev->dbbuf_dbs_dma_addr,
 					    GFP_KERNEL);
 	if (!dev->dbbuf_dbs)
-		return -ENOMEM;
+		goto fail;
 	dev->dbbuf_eis = dma_alloc_coherent(dev->dev, mem_size,
 					    &dev->dbbuf_eis_dma_addr,
 					    GFP_KERNEL);
-	if (!dev->dbbuf_eis) {
-		dma_free_coherent(dev->dev, mem_size,
-				  dev->dbbuf_dbs, dev->dbbuf_dbs_dma_addr);
-		dev->dbbuf_dbs = NULL;
-		return -ENOMEM;
-	}
+	if (!dev->dbbuf_eis)
+		goto fail_free_dbbuf_dbs;
+	return;
 
-	return 0;
+fail_free_dbbuf_dbs:
+	dma_free_coherent(dev->dev, mem_size, dev->dbbuf_dbs,
+			  dev->dbbuf_dbs_dma_addr);
+	dev->dbbuf_dbs = NULL;
+fail:
+	dev_warn(dev->dev, "unable to allocate dma for dbbuf\n");
 }
 
 static void nvme_dbbuf_dma_free(struct nvme_dev *dev)
@@ -2855,11 +2847,16 @@ static void nvme_reset_work(struct work_struct *work)
 	if (result)
 		goto out;
 
-	if (dev->ctrl.oacs & NVME_CTRL_OACS_DBBUF_SUPP) {
-		result = nvme_dbbuf_dma_alloc(dev);
-		if (result)
-			dev_warn(dev->dev,
-				 "unable to allocate dma for dbbuf\n");
+	if (dev->dbbuf_dbs) {
+		/*
+		 * Clear the dbbuf memory so the driver doesn't observe stale
+		 * values from the previous instantiation.
+		 */
+		memset(dev->dbbuf_dbs, 0, nvme_dbbuf_size(dev));
+		memset(dev->dbbuf_eis, 0, nvme_dbbuf_size(dev));
+	} else {
+		if (dev->ctrl.oacs & NVME_CTRL_OACS_DBBUF_SUPP)
+			nvme_dbbuf_dma_alloc(dev);
 	}
 
 	if (dev->ctrl.hmpre) {
-- 
2.30.2