Driver Core: add ability for class_find_device to start in middle of list

This mirrors the functionality that driver_find_device has as well. We add a start variable, and all callers of the function are fixed up at the same time. The block layer will be using this new functionality in a follow-on patch. Cc: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Driver Core: add ability for class_find_device to start in middle of list
This mirrors the functionality that driver_find_device has as well. We add a start variable, and all callers of the function are fixed up at the same time. The block layer will be using this new functionality in a follow-on patch. Cc: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Greg Kroah-Hartman
1 parent 93562b5376
Showing 8 changed files with 28 additions and 19 deletions Side-by-side Diff
drivers/base/class.c
drivers/base/core.c
drivers/ieee1394/nodemgr.c
drivers/rtc/interface.c
drivers/scsi/hosts.c
drivers/scsi/scsi_transport_iscsi.c
drivers/spi/spi.c
include/linux/device.h
@@ -302,6 +302,7 @@
 /**
  * class_find_device - device iterator for locating a particular device
  * @class: the class we're iterating
+ * @start: Device to begin with
  * @data: data for the match function
  * @match: function to check device
  *
@@ -319,8 +320,9 @@
  * re-acquired in @match, otherwise it will self-deadlocking. For
  * example, calls to add or remove class members would be verboten.
  */
-struct device *class_find_device(struct class *class, void *data,
-				   int (*match)(struct device *, void *))
+struct device *class_find_device(struct class *class, struct device *start,
+				 void *data,
+				 int (*match)(struct device *, void *))
 {
 	struct device *dev;
 	int found = 0;
  
  
@@ -330,15 +332,17 @@
  
 	down(&class->sem);
 	list_for_each_entry(dev, &class->devices, node) {
+		if (start) {
+			if (start == dev)
+				start = NULL;
+			continue;
+		}
 		dev = get_device(dev);
-		if (dev) {
-			if (match(dev, data)) {
-				found = 1;
-				break;
-			} else
-				put_device(dev);
-		} else
+		if (match(dev, data)) {
+			found = 1;
 			break;
+		} else
+			put_device(dev);
 	}
 	up(&class->sem);
  
@@ -1289,7 +1289,7 @@
 {
 	struct device *dev;
  
-	dev = class_find_device(class, &devt, __match_devt);
+	dev = class_find_device(class, NULL, &devt, __match_devt);
 	if (dev) {
 		put_device(dev);
 		device_unregister(dev);
@@ -754,7 +754,8 @@
 	 */
 	mutex_lock(&nodemgr_serialize_remove_uds);
 	for (;;) {
-		dev = class_find_device(&nodemgr_ud_class, ne, __match_ne);
+		dev = class_find_device(&nodemgr_ud_class, NULL, ne,
+					__match_ne);
 		if (!dev)
 			break;
 		ud = container_of(dev, struct unit_directory, unit_dev);
@@ -901,7 +902,8 @@
 	struct device *dev;
 	struct node_entry *ne;
  
-	dev = class_find_device(&nodemgr_ne_class, &guid, __match_ne_guid);
+	dev = class_find_device(&nodemgr_ne_class, NULL, &guid,
+				__match_ne_guid);
 	if (!dev)
 		return NULL;
 	ne = container_of(dev, struct node_entry, node_dev);
@@ -940,7 +942,8 @@
 	param.host = host;
 	param.nodeid = nodeid;
  
-	dev = class_find_device(&nodemgr_ne_class, &param, __match_ne_nodeid);
+	dev = class_find_device(&nodemgr_ne_class, NULL, &param,
+				__match_ne_nodeid);
 	if (!dev)
 		return NULL;
 	ne = container_of(dev, struct node_entry, node_dev);
@@ -345,7 +345,7 @@
 	struct device *dev;
 	struct rtc_device *rtc = NULL;
  
-	dev = class_find_device(rtc_class, name, __rtc_match);
+	dev = class_find_device(rtc_class, NULL, name, __rtc_match);
 	if (dev)
 		rtc = to_rtc_device(dev);
  
@@ -466,7 +466,8 @@
 	struct device *cdev;
 	struct Scsi_Host *shost = ERR_PTR(-ENXIO);
  
-	cdev = class_find_device(&shost_class, &hostnum, __scsi_host_match);
+	cdev = class_find_device(&shost_class, NULL, &hostnum,
+				 __scsi_host_match);
 	if (cdev) {
 		shost = scsi_host_get(class_to_shost(cdev));
 		put_device(cdev);
@@ -170,7 +170,7 @@
 	int err;
  
 	for (id = 1; id < ISCSI_MAX_EPID; id++) {
-		dev = class_find_device(&iscsi_endpoint_class, &id,
+		dev = class_find_device(&iscsi_endpoint_class, NULL, &id,
 					iscsi_match_epid);
 		if (!dev)
 			break;
@@ -222,7 +222,7 @@
 	struct iscsi_endpoint *ep;
 	struct device *dev;
  
-	dev = class_find_device(&iscsi_endpoint_class, &handle,
+	dev = class_find_device(&iscsi_endpoint_class, NULL, &handle,
 				iscsi_match_epid);
 	if (!dev)
 		return NULL;
@@ -502,7 +502,7 @@
 	struct device		*dev;
 	struct spi_master	*master = NULL;
  
-	dev = class_find_device(&spi_master_class, &bus_num,
+	dev = class_find_device(&spi_master_class, NULL, &bus_num,
 				__spi_master_match);
 	if (dev)
 		master = container_of(dev, struct spi_master, dev);
@@ -213,7 +213,8 @@
 extern int class_for_each_device(struct class *class, struct device *start,
 				 void *data,
 				 int (*fn)(struct device *dev, void *data));
-extern struct device *class_find_device(struct class *class, void *data,
+extern struct device *class_find_device(struct class *class,
+					struct device *start, void *data,
 					int (*match)(struct device *, void *));
  
 struct class_attribute {
...	...	@@ -302,6 +302,7 @@
302	302	/**
303	303	* class_find_device - device iterator for locating a particular device
304	304	* @class: the class we're iterating
	305	+ * @start: Device to begin with
305	306	* @data: data for the match function
306	307	* @match: function to check device
307	308	*
...	...	@@ -319,8 +320,9 @@
319	320	* re-acquired in @match, otherwise it will self-deadlocking. For
320	321	* example, calls to add or remove class members would be verboten.
321	322	*/
322		-struct device class_find_device(struct class class, void *data,
323		- int (match)(struct device , void *))
	323	+struct device class_find_device(struct class class, struct device *start,
	324	+ void *data,
	325	+ int (match)(struct device , void *))
324	326	{
325	327	struct device *dev;
326	328	int found = 0;
327	329
328	330
...	...	@@ -330,15 +332,17 @@
330	332
331	333	down(&class->sem);
332	334	list_for_each_entry(dev, &class->devices, node) {
	335	+ if (start) {
	336	+ if (start == dev)
	337	+ start = NULL;
	338	+ continue;
	339	+ }
333	340	dev = get_device(dev);
334		- if (dev) {
335		- if (match(dev, data)) {
336		- found = 1;
337		- break;
338		- } else
339		- put_device(dev);
340		- } else
	341	+ if (match(dev, data)) {
	342	+ found = 1;
341	343	break;
	344	+ } else
	345	+ put_device(dev);
342	346	}
343	347	up(&class->sem);
344	348
...	...	@@ -1289,7 +1289,7 @@
1289	1289	{
1290	1290	struct device *dev;
1291	1291
1292		- dev = class_find_device(class, &devt, __match_devt);
	1292	+ dev = class_find_device(class, NULL, &devt, __match_devt);
1293	1293	if (dev) {
1294	1294	put_device(dev);
1295	1295	device_unregister(dev);
...	...	@@ -754,7 +754,8 @@
754	754	*/
755	755	mutex_lock(&nodemgr_serialize_remove_uds);
756	756	for (;;) {
757		- dev = class_find_device(&nodemgr_ud_class, ne, __match_ne);
	757	+ dev = class_find_device(&nodemgr_ud_class, NULL, ne,
	758	+ __match_ne);
758	759	if (!dev)
759	760	break;
760	761	ud = container_of(dev, struct unit_directory, unit_dev);
...	...	@@ -901,7 +902,8 @@
901	902	struct device *dev;
902	903	struct node_entry *ne;
903	904
904		- dev = class_find_device(&nodemgr_ne_class, &guid, __match_ne_guid);
	905	+ dev = class_find_device(&nodemgr_ne_class, NULL, &guid,
	906	+ __match_ne_guid);
905	907	if (!dev)
906	908	return NULL;
907	909	ne = container_of(dev, struct node_entry, node_dev);
...	...	@@ -940,7 +942,8 @@
940	942	param.host = host;
941	943	param.nodeid = nodeid;
942	944
943		- dev = class_find_device(&nodemgr_ne_class, &param, __match_ne_nodeid);
	945	+ dev = class_find_device(&nodemgr_ne_class, NULL, &param,
	946	+ __match_ne_nodeid);
944	947	if (!dev)
945	948	return NULL;
946	949	ne = container_of(dev, struct node_entry, node_dev);
...	...	@@ -345,7 +345,7 @@
345	345	struct device *dev;
346	346	struct rtc_device *rtc = NULL;
347	347
348		- dev = class_find_device(rtc_class, name, __rtc_match);
	348	+ dev = class_find_device(rtc_class, NULL, name, __rtc_match);
349	349	if (dev)
350	350	rtc = to_rtc_device(dev);
351	351
...	...	@@ -466,7 +466,8 @@
466	466	struct device *cdev;
467	467	struct Scsi_Host *shost = ERR_PTR(-ENXIO);
468	468
469		- cdev = class_find_device(&shost_class, &hostnum, __scsi_host_match);
	469	+ cdev = class_find_device(&shost_class, NULL, &hostnum,
	470	+ __scsi_host_match);
470	471	if (cdev) {
471	472	shost = scsi_host_get(class_to_shost(cdev));
472	473	put_device(cdev);
...	...	@@ -170,7 +170,7 @@
170	170	int err;
171	171
172	172	for (id = 1; id < ISCSI_MAX_EPID; id++) {
173		- dev = class_find_device(&iscsi_endpoint_class, &id,
	173	+ dev = class_find_device(&iscsi_endpoint_class, NULL, &id,
174	174	iscsi_match_epid);
175	175	if (!dev)
176	176	break;
...	...	@@ -222,7 +222,7 @@
222	222	struct iscsi_endpoint *ep;
223	223	struct device *dev;
224	224
225		- dev = class_find_device(&iscsi_endpoint_class, &handle,
	225	+ dev = class_find_device(&iscsi_endpoint_class, NULL, &handle,
226	226	iscsi_match_epid);
227	227	if (!dev)
228	228	return NULL;
...	...	@@ -502,7 +502,7 @@
502	502	struct device *dev;
503	503	struct spi_master *master = NULL;
504	504
505		- dev = class_find_device(&spi_master_class, &bus_num,
	505	+ dev = class_find_device(&spi_master_class, NULL, &bus_num,
506	506	__spi_master_match);
507	507	if (dev)
508	508	master = container_of(dev, struct spi_master, dev);
...	...	@@ -213,7 +213,8 @@
213	213	extern int class_for_each_device(struct class class, struct device start,
214	214	void *data,
215	215	int (fn)(struct device dev, void *data));
216		-extern struct device class_find_device(struct class class, void *data,
	216	+extern struct device class_find_device(struct class class,
	217	+ struct device start, void data,
217	218	int (match)(struct device , void *));
218	219
219	220	struct class_attribute {