[PATCH 4/5 (take 2)] sysfs: (driver/block) if show/store is missing return -EIO

[Dmitry Torokhov <dtor_core@ameritech.net>]

sysfs: fix drivers/block so if an attribute doesn't implement
       show or store method read/write will return -EIO
       instead of 0 or -EINVAL.

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
---

 as-iosched.c       |    4 ++--
 cfq-iosched.c      |    4 ++--
 deadline-iosched.c |    4 ++--
 genhd.c            |    2 +-
 ll_rw_blk.c        |    4 ++--
 5 files changed, 9 insertions(+), 9 deletions(-)

Index: dtor/drivers/block/as-iosched.c
===================================================================
--- dtor.orig/drivers/block/as-iosched.c
+++ dtor/drivers/block/as-iosched.c
@@ -2044,7 +2044,7 @@ as_attr_show(struct kobject *kobj, struc
 	struct as_fs_entry *entry = to_as(attr);
 
 	if (!entry->show)
-		return 0;
+		return -EIO;
 
 	return entry->show(e->elevator_data, page);
 }
@@ -2057,7 +2057,7 @@ as_attr_store(struct kobject *kobj, stru
 	struct as_fs_entry *entry = to_as(attr);
 
 	if (!entry->store)
-		return -EINVAL;
+		return -EIO;
 
 	return entry->store(e->elevator_data, page, length);
 }
Index: dtor/drivers/block/cfq-iosched.c
===================================================================
--- dtor.orig/drivers/block/cfq-iosched.c
+++ dtor/drivers/block/cfq-iosched.c
@@ -1772,7 +1772,7 @@ cfq_attr_show(struct kobject *kobj, stru
 	struct cfq_fs_entry *entry = to_cfq(attr);
 
 	if (!entry->show)
-		return 0;
+		return -EIO;
 
 	return entry->show(e->elevator_data, page);
 }
@@ -1785,7 +1785,7 @@ cfq_attr_store(struct kobject *kobj, str
 	struct cfq_fs_entry *entry = to_cfq(attr);
 
 	if (!entry->store)
-		return -EINVAL;
+		return -EIO;
 
 	return entry->store(e->elevator_data, page, length);
 }
Index: dtor/drivers/block/genhd.c
===================================================================
--- dtor.orig/drivers/block/genhd.c
+++ dtor/drivers/block/genhd.c
@@ -321,7 +321,7 @@ static ssize_t disk_attr_show(struct kob
 	struct gendisk *disk = to_disk(kobj);
 	struct disk_attribute *disk_attr =
 		container_of(attr,struct disk_attribute,attr);
-	ssize_t ret = 0;
+	ssize_t ret = -EIO;
 
 	if (disk_attr->show)
 		ret = disk_attr->show(disk,page);
Index: dtor/drivers/block/ll_rw_blk.c
===================================================================
--- dtor.orig/drivers/block/ll_rw_blk.c
+++ dtor/drivers/block/ll_rw_blk.c
@@ -3582,7 +3582,7 @@ queue_attr_show(struct kobject *kobj, st
 
 	q = container_of(kobj, struct request_queue, kobj);
 	if (!entry->show)
-		return 0;
+		return -EIO;
 
 	return entry->show(q, page);
 }
@@ -3596,7 +3596,7 @@ queue_attr_store(struct kobject *kobj, s
 
 	q = container_of(kobj, struct request_queue, kobj);
 	if (!entry->store)
-		return -EINVAL;
+		return -EIO;
 
 	return entry->store(q, page, length);
 }
Index: dtor/drivers/block/deadline-iosched.c
===================================================================
--- dtor.orig/drivers/block/deadline-iosched.c
+++ dtor/drivers/block/deadline-iosched.c
@@ -886,7 +886,7 @@ deadline_attr_show(struct kobject *kobj,
 	struct deadline_fs_entry *entry = to_deadline(attr);
 
 	if (!entry->show)
-		return 0;
+		return -EIO;
 
 	return entry->show(e->elevator_data, page);
 }
@@ -899,7 +899,7 @@ deadline_attr_store(struct kobject *kobj
 	struct deadline_fs_entry *entry = to_deadline(attr);
 
 	if (!entry->store)
-		return -EINVAL;
+		return -EIO;
 
 	return entry->store(e->elevator_data, page, length);
 }