UIO: fix Greg's stupid changes

This fixes two bugs with UIO that cropped up recently in -rc1

1) WARNING: at fs/sysfs/file.c:334 sysfs_open_file when trying to open
   a map addr/size file - complaining about missing sysfs_ops for ktype

2) Permission denied when reading uio/uio0/maps/map0/{addr,size} when
   files are mode S_IRUGO

Also fix a typo: attr_attribute -> addr_attribute

Signed-off-by: Brandon Philips <bphilips@suse.de>
Signed-off-by: Hans J. Koch <hjk@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/uio/uio.c b/drivers/uio/uio.c
index 2a77e9d..e8a01f2 100644 (file)
--- a/drivers/uio/uio.c
+++ b/drivers/uio/uio.c
@@ -57,29 +57,29 @@ struct uio_map {
 };
 #define to_map(map) container_of(map, struct uio_map, kobj)
 
-
-static ssize_t map_attr_show(struct kobject *kobj, struct kobj_attribute *attr,
-                            char *buf)
+static ssize_t map_addr_show(struct uio_mem *mem, char *buf)
 {
-       struct uio_map *map = to_map(kobj);
-       struct uio_mem *mem = map->mem;
-
-       if (strncmp(attr->attr.name, "addr", 4) == 0)
-               return sprintf(buf, "0x%lx\n", mem->addr);
-
-       if (strncmp(attr->attr.name, "size", 4) == 0)
-               return sprintf(buf, "0x%lx\n", mem->size);
+       return sprintf(buf, "0x%lx\n", mem->addr);
+}
 
-       return -ENODEV;
+static ssize_t map_size_show(struct uio_mem *mem, char *buf)
+{
+       return sprintf(buf, "0x%lx\n", mem->size);
 }
 
-static struct kobj_attribute attr_attribute =
-       __ATTR(addr, S_IRUGO, map_attr_show, NULL);
-static struct kobj_attribute size_attribute =
-       __ATTR(size, S_IRUGO, map_attr_show, NULL);
+struct uio_sysfs_entry {
+       struct attribute attr;
+       ssize_t (*show)(struct uio_mem *, char *);
+       ssize_t (*store)(struct uio_mem *, const char *, size_t);
+};
+
+static struct uio_sysfs_entry addr_attribute =
+       __ATTR(addr, S_IRUGO, map_addr_show, NULL);
+static struct uio_sysfs_entry size_attribute =
+       __ATTR(size, S_IRUGO, map_size_show, NULL);
 
 static struct attribute *attrs[] = {
-       &attr_attribute.attr,
+       &addr_attribute.attr,
        &size_attribute.attr,
        NULL,   /* need to NULL terminate the list of attributes */
 };
@@ -90,8 +90,28 @@ static void map_release(struct kobject *kobj)
        kfree(map);
 }
 
+static ssize_t map_type_show(struct kobject *kobj, struct attribute *attr,
+                            char *buf)
+{
+       struct uio_map *map = to_map(kobj);
+       struct uio_mem *mem = map->mem;
+       struct uio_sysfs_entry *entry;
+
+       entry = container_of(attr, struct uio_sysfs_entry, attr);
+
+       if (!entry->show)
+               return -EIO;
+
+       return entry->show(mem, buf);
+}
+
+static struct sysfs_ops uio_sysfs_ops = {
+       .show = map_type_show,
+};
+
 static struct kobj_type map_attr_type = {
        .release        = map_release,
+       .sysfs_ops      = &uio_sysfs_ops,
        .default_attrs  = attrs,
 };