pci: Add PCI LRDT tag size and section size

This patch adds a preprocessor constant to describe the PCI VPD large
resource data type tag size and an inline function to extract the large
resource section size from the large resource data type tag.
Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/bnx2.c

@@ -7773,15 +7773,17 @@ bnx2_read_vpd_fw_ver(struct bnx2 *bp)
 		unsigned int block_end;
 
 		if (val == 0x82 || val == 0x91) {
-			i = (i + 3 + (data[i + 1] + (data[i + 2] << 8)));
+			i += PCI_VPD_LRDT_TAG_SIZE +
+			     pci_vpd_lrdt_size(&data[i]);
 			continue;
 		}
 
 		if (val != 0x90)
 			goto vpd_done;
 
-		block_end = (i + 3 + (data[i + 1] + (data[i + 2] << 8)));
-		i += 3;
+		block_end = (i + PCI_VPD_LRDT_TAG_SIZE +
+			    pci_vpd_lrdt_size(&data[i]));
+		i += PCI_VPD_LRDT_TAG_SIZE;
 
 		if (block_end > BNX2_VPD_LEN)
 			goto vpd_done;

drivers/net/tg3.c

@@ -12590,19 +12590,18 @@ static void __devinit tg3_read_partno(struct tg3 *tp)
 		unsigned int block_end;
 
 		if (val == 0x82 || val == 0x91) {
-			i = (i + 3 +
-			     (vpd_data[i + 1] +
-			      (vpd_data[i + 2] << 8)));
+			i += PCI_VPD_LRDT_TAG_SIZE +
+			     pci_vpd_lrdt_size(&vpd_data[i]);
 			continue;
 		}
 
 		if (val != 0x90)
 			goto out_not_found;
 
-		block_end = (i + 3 +
-			     (vpd_data[i + 1] +
-			      (vpd_data[i + 2] << 8)));
-		i += 3;
+		block_end = i + PCI_VPD_LRDT_TAG_SIZE +
+			    pci_vpd_lrdt_size(&vpd_data[i]);
+
+		i += PCI_VPD_LRDT_TAG_SIZE;
 
 		if (block_end > TG3_NVM_VPD_LEN)
 			goto out_not_found;

include/linux/pci.h

@@ -1349,5 +1349,19 @@ static inline bool pci_is_pcie(struct pci_dev *dev)
 
 void pci_request_acs(void);
 
+
+#define PCI_VPD_LRDT_TAG_SIZE	3
+
+/**
+ * pci_vpd_lrdt_size - Extracts the Large Resource Data Type length
+ * @lrdt: Pointer to the beginning of the Large Resource Data Type tag
+ *
+ * Returns the extracted Large Resource Data Type length.
+ */
+static inline u16 pci_vpd_lrdt_size(const u8 *lrdt)
+{
+	return (u16)lrdt[1] + ((u16)lrdt[2] << 8);
+}
+
 #endif /* __KERNEL__ */
 #endif /* LINUX_PCI_H */