ie31200_edac: Allocate mci and map mchbar first

Check for memory allocation and mchbar mapping failures before
initializing the dimm info tables needlessly.

Signed-off-by: Jason Baron <jbaron@akamai.com>
Suggested-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/ead8f53e699f1ce21c2e17f3cffb4685d4faf72a.1404939455.git.jbaron@akamai.com
Signed-off-by: Borislav Petkov <bp@suse.de>

drivers/edac/ie31200_edac.c

@@ -328,8 +328,7 @@ static void __iomem *ie31200_map_mchbar(struct pci_dev *pdev)
 
 static int ie31200_probe1(struct pci_dev *pdev, int dev_idx)
 {
-	int rc;
-	int i, j;
+	int i, j, ret;
 	struct mem_ctl_info *mci = NULL;
 	struct edac_mc_layer layers[2];
 	struct dimm_data dimm_info[IE31200_CHANNELS][IE31200_DIMMS_PER_CHANNEL];
@@ -344,31 +343,7 @@ static int ie31200_probe1(struct pci_dev *pdev, int dev_idx)
 		return -ENODEV;
 	}
 
-	window = ie31200_map_mchbar(pdev);
-	if (!window)
-		return -ENODEV;
-
-	/* populate DIMM info */
-	for (i = 0; i < IE31200_CHANNELS; i++) {
-		addr_decode = readl(window + IE31200_MAD_DIMM_0_OFFSET +
-					(i * 4));
-		edac_dbg(0, "addr_decode: 0x%x\n", addr_decode);
-		for (j = 0; j < IE31200_DIMMS_PER_CHANNEL; j++) {
-			dimm_info[i][j].size = (addr_decode >> (j * 8)) &
-						IE31200_MAD_DIMM_SIZE;
-			dimm_info[i][j].dual_rank = (addr_decode &
-				(IE31200_MAD_DIMM_A_RANK << j)) ? 1 : 0;
-			dimm_info[i][j].x16_width = (addr_decode &
-				(IE31200_MAD_DIMM_A_WIDTH << j)) ? 1 : 0;
-			edac_dbg(0, "size: 0x%x, rank: %d, width: %d\n",
-				 dimm_info[i][j].size,
-				 dimm_info[i][j].dual_rank,
-				 dimm_info[i][j].x16_width);
-		}
-	}
-
 	nr_channels = how_many_channels(pdev);
-
 	layers[0].type = EDAC_MC_LAYER_CHIP_SELECT;
 	layers[0].size = IE31200_DIMMS;
 	layers[0].is_virt_csrow = true;
@@ -377,19 +352,20 @@ static int ie31200_probe1(struct pci_dev *pdev, int dev_idx)
 	layers[1].is_virt_csrow = false;
 	mci = edac_mc_alloc(0, ARRAY_SIZE(layers), layers,
 			    sizeof(struct ie31200_priv));
-
-	rc = -ENOMEM;
 	if (!mci)
-		goto fail_unmap;
+		return -ENOMEM;
 
-	edac_dbg(3, "MC: init mci\n");
+	window = ie31200_map_mchbar(pdev);
+	if (!window) {
+		ret = -ENODEV;
+		goto fail_free;
+	}
 
+	edac_dbg(3, "MC: init mci\n");
 	mci->pdev = &pdev->dev;
 	mci->mtype_cap = MEM_FLAG_DDR3;
-
 	mci->edac_ctl_cap = EDAC_FLAG_SECDED;
 	mci->edac_cap = EDAC_FLAG_SECDED;
-
 	mci->mod_name = EDAC_MOD_STR;
 	mci->mod_ver = IE31200_REVISION;
 	mci->ctl_name = ie31200_devs[dev_idx].ctl_name;
@@ -399,6 +375,25 @@ static int ie31200_probe1(struct pci_dev *pdev, int dev_idx)
 	priv = mci->pvt_info;
 	priv->window = window;
 
+	/* populate DIMM info */
+	for (i = 0; i < IE31200_CHANNELS; i++) {
+		addr_decode = readl(window + IE31200_MAD_DIMM_0_OFFSET +
+					(i * 4));
+		edac_dbg(0, "addr_decode: 0x%x\n", addr_decode);
+		for (j = 0; j < IE31200_DIMMS_PER_CHANNEL; j++) {
+			dimm_info[i][j].size = (addr_decode >> (j * 8)) &
+						IE31200_MAD_DIMM_SIZE;
+			dimm_info[i][j].dual_rank = (addr_decode &
+				(IE31200_MAD_DIMM_A_RANK << j)) ? 1 : 0;
+			dimm_info[i][j].x16_width = (addr_decode &
+				(IE31200_MAD_DIMM_A_WIDTH << j)) ? 1 : 0;
+			edac_dbg(0, "size: 0x%x, rank: %d, width: %d\n",
+				 dimm_info[i][j].size,
+				 dimm_info[i][j].dual_rank,
+				 dimm_info[i][j].x16_width);
+		}
+	}
+
 	/*
 	 * The dram rank boundary (DRB) reg values are boundary addresses
 	 * for each DRAM rank with a granularity of 64MB.  DRB regs are
@@ -439,23 +434,23 @@ static int ie31200_probe1(struct pci_dev *pdev, int dev_idx)
 
 	ie31200_clear_error_info(mci);
 
-	rc = -ENODEV;
 	if (edac_mc_add_mc(mci)) {
 		edac_dbg(3, "MC: failed edac_mc_add_mc()\n");
-		goto fail_free;
+		ret = -ENODEV;
+		goto fail_unmap;
 	}
 
 	/* get this far and it's successful */
 	edac_dbg(3, "MC: success\n");
 	return 0;
 
-fail_free:
-	if (mci)
-		edac_mc_free(mci);
 fail_unmap:
 	iounmap(window);
 
-	return rc;
+fail_free:
+	edac_mc_free(mci);
+
+	return ret;
 }
 
 static int ie31200_init_one(struct pci_dev *pdev,