xen/pciback: Drop two backends, squash and cleanup some code.

 - Remove the slot and controller controller backend as they
   are not used.
 - Document the find pciback_[read|write]_config_[byte|word|dword]
   to make it easier to find.
 - Collapse the code from conf_space_capability_msi into pciback_ops.c
 - Collapse conf_space_capability_[pm|vpd].c in conf_space_capability.c
   [and remove the conf_space_capability.h file]
 - Rename all visible functions from pciback to xen_pcibk.
 - Rename all the printk/pr_info, etc that use the "pciback" to say
   "xen-pciback".
 - Convert functions that are not referenced outside the code to be
   static to save on name space.
 - Do the same thing for structures that are internal to the driver.
 - Run checkpatch.pl after the renames and fixup its warnings and
   fix any compile errors caused by the variable rename
 - Cleanup any structs that checkpath.pl commented about or just
   look odd.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
diff --git a/drivers/xen/xen-pciback/conf_space_header.c b/drivers/xen/xen-pciback/conf_space_header.c
index 22ad0f5..da3cbdf 100644
--- a/drivers/xen/xen-pciback/conf_space_header.c
+++ b/drivers/xen/xen-pciback/conf_space_header.c
@@ -15,6 +15,7 @@
 	int which;
 };
 
+#define DRV_NAME	"xen-pciback"
 #define is_enable_cmd(value) ((value)&(PCI_COMMAND_MEMORY|PCI_COMMAND_IO))
 #define is_master_cmd(value) ((value)&PCI_COMMAND_MASTER)
 
@@ -23,7 +24,7 @@
 	int i;
 	int ret;
 
-	ret = pciback_read_config_word(dev, offset, value, data);
+	ret = xen_pcibk_read_config_word(dev, offset, value, data);
 	if (!atomic_read(&dev->enable_cnt))
 		return ret;
 
@@ -39,13 +40,13 @@
 
 static int command_write(struct pci_dev *dev, int offset, u16 value, void *data)
 {
-	struct pciback_dev_data *dev_data;
+	struct xen_pcibk_dev_data *dev_data;
 	int err;
 
 	dev_data = pci_get_drvdata(dev);
 	if (!pci_is_enabled(dev) && is_enable_cmd(value)) {
 		if (unlikely(verbose_request))
-			printk(KERN_DEBUG "pciback: %s: enable\n",
+			printk(KERN_DEBUG DRV_NAME ": %s: enable\n",
 			       pci_name(dev));
 		err = pci_enable_device(dev);
 		if (err)
@@ -54,7 +55,7 @@
 			dev_data->enable_intx = 1;
 	} else if (pci_is_enabled(dev) && !is_enable_cmd(value)) {
 		if (unlikely(verbose_request))
-			printk(KERN_DEBUG "pciback: %s: disable\n",
+			printk(KERN_DEBUG DRV_NAME ": %s: disable\n",
 			       pci_name(dev));
 		pci_disable_device(dev);
 		if (dev_data)
@@ -63,7 +64,7 @@
 
 	if (!dev->is_busmaster && is_master_cmd(value)) {
 		if (unlikely(verbose_request))
-			printk(KERN_DEBUG "pciback: %s: set bus master\n",
+			printk(KERN_DEBUG DRV_NAME ": %s: set bus master\n",
 			       pci_name(dev));
 		pci_set_master(dev);
 	}
@@ -71,12 +72,12 @@
 	if (value & PCI_COMMAND_INVALIDATE) {
 		if (unlikely(verbose_request))
 			printk(KERN_DEBUG
-			       "pciback: %s: enable memory-write-invalidate\n",
+			       DRV_NAME ": %s: enable memory-write-invalidate\n",
 			       pci_name(dev));
 		err = pci_set_mwi(dev);
 		if (err) {
 			printk(KERN_WARNING
-			       "pciback: %s: cannot enable "
+			       DRV_NAME ": %s: cannot enable "
 			       "memory-write-invalidate (%d)\n",
 			       pci_name(dev), err);
 			value &= ~PCI_COMMAND_INVALIDATE;
@@ -91,7 +92,7 @@
 	struct pci_bar_info *bar = data;
 
 	if (unlikely(!bar)) {
-		printk(KERN_WARNING "pciback: driver data not found for %s\n",
+		printk(KERN_WARNING DRV_NAME ": driver data not found for %s\n",
 		       pci_name(dev));
 		return XEN_PCI_ERR_op_failed;
 	}
@@ -125,7 +126,7 @@
 	struct pci_bar_info *bar = data;
 
 	if (unlikely(!bar)) {
-		printk(KERN_WARNING "pciback: driver data not found for %s\n",
+		printk(KERN_WARNING DRV_NAME ": driver data not found for %s\n",
 		       pci_name(dev));
 		return XEN_PCI_ERR_op_failed;
 	}
@@ -153,7 +154,7 @@
 	struct pci_bar_info *bar = data;
 
 	if (unlikely(!bar)) {
-		printk(KERN_WARNING "pciback: driver data not found for %s\n",
+		printk(KERN_WARNING DRV_NAME ": driver data not found for %s\n",
 		       pci_name(dev));
 		return XEN_PCI_ERR_op_failed;
 	}
@@ -227,7 +228,7 @@
 	kfree(data);
 }
 
-static int pciback_read_vendor(struct pci_dev *dev, int offset,
+static int xen_pcibk_read_vendor(struct pci_dev *dev, int offset,
 			       u16 *value, void *data)
 {
 	*value = dev->vendor;
@@ -235,7 +236,7 @@
 	return 0;
 }
 
-static int pciback_read_device(struct pci_dev *dev, int offset,
+static int xen_pcibk_read_device(struct pci_dev *dev, int offset,
 			       u16 *value, void *data)
 {
 	*value = dev->device;
@@ -272,12 +273,12 @@
 	{
 	 .offset    = PCI_VENDOR_ID,
 	 .size      = 2,
-	 .u.w.read  = pciback_read_vendor,
+	 .u.w.read  = xen_pcibk_read_vendor,
 	},
 	{
 	 .offset    = PCI_DEVICE_ID,
 	 .size      = 2,
-	 .u.w.read  = pciback_read_device,
+	 .u.w.read  = xen_pcibk_read_device,
 	},
 	{
 	 .offset    = PCI_COMMAND,
@@ -293,24 +294,24 @@
 	{
 	 .offset    = PCI_INTERRUPT_PIN,
 	 .size      = 1,
-	 .u.b.read  = pciback_read_config_byte,
+	 .u.b.read  = xen_pcibk_read_config_byte,
 	},
 	{
 	 /* Any side effects of letting driver domain control cache line? */
 	 .offset    = PCI_CACHE_LINE_SIZE,
 	 .size      = 1,
-	 .u.b.read  = pciback_read_config_byte,
-	 .u.b.write = pciback_write_config_byte,
+	 .u.b.read  = xen_pcibk_read_config_byte,
+	 .u.b.write = xen_pcibk_write_config_byte,
 	},
 	{
 	 .offset    = PCI_LATENCY_TIMER,
 	 .size      = 1,
-	 .u.b.read  = pciback_read_config_byte,
+	 .u.b.read  = xen_pcibk_read_config_byte,
 	},
 	{
 	 .offset    = PCI_BIST,
 	 .size      = 1,
-	 .u.b.read  = pciback_read_config_byte,
+	 .u.b.read  = xen_pcibk_read_config_byte,
 	 .u.b.write = bist_write,
 	},
 	{}
@@ -356,26 +357,26 @@
 	{}
 };
 
-int pciback_config_header_add_fields(struct pci_dev *dev)
+int xen_pcibk_config_header_add_fields(struct pci_dev *dev)
 {
 	int err;
 
-	err = pciback_config_add_fields(dev, header_common);
+	err = xen_pcibk_config_add_fields(dev, header_common);
 	if (err)
 		goto out;
 
 	switch (dev->hdr_type) {
 	case PCI_HEADER_TYPE_NORMAL:
-		err = pciback_config_add_fields(dev, header_0);
+		err = xen_pcibk_config_add_fields(dev, header_0);
 		break;
 
 	case PCI_HEADER_TYPE_BRIDGE:
-		err = pciback_config_add_fields(dev, header_1);
+		err = xen_pcibk_config_add_fields(dev, header_1);
 		break;
 
 	default:
 		err = -EINVAL;
-		printk(KERN_ERR "pciback: %s: Unsupported header type %d!\n",
+		printk(KERN_ERR DRV_NAME ": %s: Unsupported header type %d!\n",
 		       pci_name(dev), dev->hdr_type);
 		break;
 	}