xen/pciback: miscellaneous adjustments

This is a minor bugfix and a set of small cleanups; as it is not clear
whether this needs splitting into pieces (and if so, at what
granularity), it is a single combined patch.
- add a missing return statement to an error path in
  kill_domain_by_device()
- use pci_is_enabled() rather than raw atomic_read()
- remove a bogus attempt to zero-terminate an already zero-terminated
  string
- #define DRV_NAME once uniformly in the shared local header
- make DRIVER_ATTR() variables static
- eliminate a pointless use of list_for_each_entry_safe()
- add MODULE_ALIAS()
- a little bit of constification
- adjust a few messages
- remove stray semicolons from inline function definitions

Signed-off-by: Jan Beulich <jbeulich@suse.com>
[v1: Dropped the resource_size fix, altered the description]
[v2: Fixed cleanpatch.pl comments]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
diff --git a/drivers/xen/xen-pciback/pci_stub.c b/drivers/xen/xen-pciback/pci_stub.c
index aec214a..1b47480 100644
--- a/drivers/xen/xen-pciback/pci_stub.c
+++ b/drivers/xen/xen-pciback/pci_stub.c
@@ -21,8 +21,6 @@
 #include "conf_space.h"
 #include "conf_space_quirks.h"
 
-#define DRV_NAME	"xen-pciback"
-
 static char *pci_devs_to_hide;
 wait_queue_head_t xen_pcibk_aer_wait_queue;
 /*Add sem for sync AER handling and xen_pcibk remove/reconfigue ops,
@@ -514,12 +512,14 @@
 	int err;
 	char nodename[PCI_NODENAME_MAX];
 
-	if (!psdev)
+	if (!psdev) {
 		dev_err(&psdev->dev->dev,
 			"device is NULL when do AER recovery/kill_domain\n");
+		return;
+	}
+
 	snprintf(nodename, PCI_NODENAME_MAX, "/local/domain/0/backend/pci/%d/0",
 		psdev->pdev->xdev->otherend_id);
-	nodename[strlen(nodename)] = '\0';
 
 again:
 	err = xenbus_transaction_start(&xbt);
@@ -605,7 +605,7 @@
 	if (test_bit(_XEN_PCIF_active,
 		(unsigned long *)&psdev->pdev->sh_info->flags)) {
 		dev_dbg(&psdev->dev->dev,
-			"schedule pci_conf service in xen_pcibk\n");
+			"schedule pci_conf service in " DRV_NAME "\n");
 		xen_pcibk_test_and_schedule_op(psdev->pdev);
 	}
 
@@ -995,8 +995,7 @@
 		err = count;
 	return err;
 }
-
-DRIVER_ATTR(new_slot, S_IWUSR, NULL, pcistub_slot_add);
+static DRIVER_ATTR(new_slot, S_IWUSR, NULL, pcistub_slot_add);
 
 static ssize_t pcistub_slot_remove(struct device_driver *drv, const char *buf,
 				   size_t count)
@@ -1015,8 +1014,7 @@
 		err = count;
 	return err;
 }
-
-DRIVER_ATTR(remove_slot, S_IWUSR, NULL, pcistub_slot_remove);
+static DRIVER_ATTR(remove_slot, S_IWUSR, NULL, pcistub_slot_remove);
 
 static ssize_t pcistub_slot_show(struct device_driver *drv, char *buf)
 {
@@ -1039,8 +1037,7 @@
 
 	return count;
 }
-
-DRIVER_ATTR(slots, S_IRUSR, pcistub_slot_show, NULL);
+static DRIVER_ATTR(slots, S_IRUSR, pcistub_slot_show, NULL);
 
 static ssize_t pcistub_irq_handler_show(struct device_driver *drv, char *buf)
 {
@@ -1069,8 +1066,7 @@
 	spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 	return count;
 }
-
-DRIVER_ATTR(irq_handlers, S_IRUSR, pcistub_irq_handler_show, NULL);
+static DRIVER_ATTR(irq_handlers, S_IRUSR, pcistub_irq_handler_show, NULL);
 
 static ssize_t pcistub_irq_handler_switch(struct device_driver *drv,
 					  const char *buf,
@@ -1106,7 +1102,8 @@
 		err = count;
 	return err;
 }
-DRIVER_ATTR(irq_handler_state, S_IWUSR, NULL, pcistub_irq_handler_switch);
+static DRIVER_ATTR(irq_handler_state, S_IWUSR, NULL,
+		   pcistub_irq_handler_switch);
 
 static ssize_t pcistub_quirk_add(struct device_driver *drv, const char *buf,
 				 size_t count)
@@ -1170,8 +1167,8 @@
 
 	return count;
 }
-
-DRIVER_ATTR(quirks, S_IRUSR | S_IWUSR, pcistub_quirk_show, pcistub_quirk_add);
+static DRIVER_ATTR(quirks, S_IRUSR | S_IWUSR, pcistub_quirk_show,
+		   pcistub_quirk_add);
 
 static ssize_t permissive_add(struct device_driver *drv, const char *buf,
 			      size_t count)
@@ -1236,8 +1233,8 @@
 	spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 	return count;
 }
-
-DRIVER_ATTR(permissive, S_IRUSR | S_IWUSR, permissive_show, permissive_add);
+static DRIVER_ATTR(permissive, S_IRUSR | S_IWUSR, permissive_show,
+		   permissive_add);
 
 static void pcistub_exit(void)
 {
@@ -1374,3 +1371,4 @@
 module_exit(xen_pcibk_cleanup);
 
 MODULE_LICENSE("Dual BSD/GPL");
+MODULE_ALIAS("xen-backend:pci");