pci back: Various fixes.

- remove superfluous call to pciback_field_is_dup()
- fix a variable type mismatch in pciback_field_is_dup()
- make readability improvements by using the OFFSET macro
- revises quirk data output via the sysfs quirks node so that
- displayed offset information includes base_offset.

Thanks to Jambunathan K. for giving such specific bug diagnosis.

Signed-off-by: Chris Bookholt <hap10@tycho.ncsc.mil>

linux-2.6-xen-sparse/drivers/xen/pciback/conf_space.c

@@ -349,17 +349,13 @@ void pciback_config_free_dev(struct pci_dev *dev)
 
 int pciback_config_add_field_offset(struct pci_dev *dev,
 				    struct config_field *field,
-				    unsigned int offset)
+				    unsigned int base_offset)
 {
 	int err = 0;
 	struct pciback_dev_data *dev_data = pci_get_drvdata(dev);
 	struct config_field_entry *cfg_entry;
 	void *tmp;
 
-	/* silently ignore duplicate fields */
-	if (pciback_field_is_dup(dev, field->offset + offset))
-		goto out;
-
 	cfg_entry = kmalloc(sizeof(*cfg_entry), GFP_KERNEL);
 	if (!cfg_entry) {
 		err = -ENOMEM;
@@ -368,7 +364,12 @@ int pciback_config_add_field_offset(struct pci_dev *dev,
 
 	cfg_entry->data = NULL;
 	cfg_entry->field = field;
-	cfg_entry->base_offset = offset;
+	cfg_entry->base_offset = base_offset;
+
+	/* silently ignore duplicate fields */
+	err = pciback_field_is_dup(dev,OFFSET(cfg_entry));
+	if (err)
+		goto out;
 
 	if (field->init) {
 		tmp = field->init(dev, OFFSET(cfg_entry));

linux-2.6-xen-sparse/drivers/xen/pciback/conf_space_quirks.c

@@ -32,16 +32,14 @@ static inline void register_quirk(struct pciback_config_quirk *quirk)
 	list_add_tail(&quirk->quirks_list, &pciback_quirks);
 }
 
-int pciback_field_is_dup(struct pci_dev *dev, int reg)
+int pciback_field_is_dup(struct pci_dev *dev, unsigned int reg)
 {
 	int ret = 0;
 	struct pciback_dev_data *dev_data = pci_get_drvdata(dev);
-	struct config_field *field;
 	struct config_field_entry *cfg_entry;
 
 	list_for_each_entry(cfg_entry, &dev_data->config_fields, list) {
-		field = cfg_entry->field;
-		if (field->offset == reg) {
+		if ( OFFSET(cfg_entry) == reg) {
 			ret = 1;
 			break;
 		}

linux-2.6-xen-sparse/drivers/xen/pciback/conf_space_quirks.h

@@ -30,6 +30,6 @@ void pciback_config_field_free(struct config_field *field);
 
 int pciback_config_quirk_release(struct pci_dev *dev);
 
-int pciback_field_is_dup(struct pci_dev *dev, int reg);
+int pciback_field_is_dup(struct pci_dev *dev, unsigned int reg);
 
 #endif

linux-2.6-xen-sparse/drivers/xen/pciback/pci_stub.c

@@ -589,10 +589,6 @@ static int pcistub_reg_add(int domain, int bus, int slot, int func, int reg,
 	}
 	dev = psdev->dev;
 
-	/* check for duplicate field */
-	if (pciback_field_is_dup(dev, reg))
-		goto out;
-
 	field = kzalloc(sizeof(*field), GFP_ATOMIC);
 	if (!field) {
 		err = -ENOMEM;
@@ -728,10 +724,10 @@ static ssize_t pcistub_quirk_show(struct device_driver *drv, char *buf)
 			if (count >= PAGE_SIZE)
 				goto out;
 
-			count += scnprintf(buf + count, PAGE_SIZE -
-					   count, "\t\t%08x:%01x:%08x\n",
-					   field->offset, field->size,
-					   field->mask);
+			count += scnprintf(buf + count, PAGE_SIZE - count,
+					   "\t\t%08x:%01x:%08x\n",
+					   cfg_entry->base_offset + field->offset, 
+					   field->size, field->mask);
 		}
 	}