rsxx: enable error return of rsxx_eeh_save_issued_dmas()

Commit d8d595df introduced a bug where we did not check for a NULL
return from kmalloc(). Make rsxx_eeh_save_issued_dmas() return an
error for that case, and make the callers handle that.

Signed-off-by: Philip J Kelleher <pjk1939@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/drivers/block/rsxx/core.c b/drivers/block/rsxx/core.c
index 93f2819..5af21f2 100644
--- a/drivers/block/rsxx/core.c
+++ b/drivers/block/rsxx/core.c
@@ -323,10 +323,11 @@
 	return 0;
 }
 
-static void rsxx_eeh_frozen(struct pci_dev *dev)
+static int rsxx_eeh_frozen(struct pci_dev *dev)
 {
 	struct rsxx_cardinfo *card = pci_get_drvdata(dev);
 	int i;
+	int st;
 
 	dev_warn(&dev->dev, "IBM FlashSystem PCI: preparing for slot reset.\n");
 
@@ -342,7 +343,9 @@
 
 	pci_disable_device(dev);
 
-	rsxx_eeh_save_issued_dmas(card);
+	st = rsxx_eeh_save_issued_dmas(card);
+	if (st)
+		return st;
 
 	rsxx_eeh_save_issued_creg(card);
 
@@ -356,6 +359,8 @@
 					    card->ctrl[i].cmd.buf,
 					    card->ctrl[i].cmd.dma_addr);
 	}
+
+	return 0;
 }
 
 static void rsxx_eeh_failure(struct pci_dev *dev)
@@ -399,6 +404,8 @@
 static pci_ers_result_t rsxx_error_detected(struct pci_dev *dev,
 					    enum pci_channel_state error)
 {
+	int st;
+
 	if (dev->revision < RSXX_EEH_SUPPORT)
 		return PCI_ERS_RESULT_NONE;
 
@@ -407,7 +414,13 @@
 		return PCI_ERS_RESULT_DISCONNECT;
 	}
 
-	rsxx_eeh_frozen(dev);
+	st = rsxx_eeh_frozen(dev);
+	if (st) {
+		dev_err(&dev->dev, "Slot reset setup failed\n");
+		rsxx_eeh_failure(dev);
+		return PCI_ERS_RESULT_DISCONNECT;
+	}
+
 	return PCI_ERS_RESULT_NEED_RESET;
 }
 
diff --git a/drivers/block/rsxx/dma.c b/drivers/block/rsxx/dma.c
index 95047e1..7594c6d 100644
--- a/drivers/block/rsxx/dma.c
+++ b/drivers/block/rsxx/dma.c
@@ -980,7 +980,7 @@
 	}
 }
 
-void rsxx_eeh_save_issued_dmas(struct rsxx_cardinfo *card)
+int rsxx_eeh_save_issued_dmas(struct rsxx_cardinfo *card)
 {
 	int i;
 	int j;
@@ -990,6 +990,8 @@
 
 	issued_dmas = kzalloc(sizeof(*issued_dmas) * card->n_targets,
 			      GFP_KERNEL);
+	if (!issued_dmas)
+		return -ENOMEM;
 
 	for (i = 0; i < card->n_targets; i++) {
 		INIT_LIST_HEAD(&issued_dmas[i]);
@@ -1030,6 +1032,8 @@
 	}
 
 	kfree(issued_dmas);
+
+	return 0;
 }
 
 void rsxx_eeh_cancel_dmas(struct rsxx_cardinfo *card)
diff --git a/drivers/block/rsxx/rsxx_priv.h b/drivers/block/rsxx/rsxx_priv.h
index 8a7ac87..382e8bf 100644
--- a/drivers/block/rsxx/rsxx_priv.h
+++ b/drivers/block/rsxx/rsxx_priv.h
@@ -381,7 +381,7 @@
 			   rsxx_dma_cb cb,
 			   void *cb_data);
 int rsxx_hw_buffers_init(struct pci_dev *dev, struct rsxx_dma_ctrl *ctrl);
-void rsxx_eeh_save_issued_dmas(struct rsxx_cardinfo *card);
+int rsxx_eeh_save_issued_dmas(struct rsxx_cardinfo *card);
 void rsxx_eeh_cancel_dmas(struct rsxx_cardinfo *card);
 int rsxx_eeh_remap_dmas(struct rsxx_cardinfo *card);