These changes are the raw update to linux-4.4.6-rt14. Kernel sources

[kvmfornfv.git] / kernel / drivers / char / misc.c

diff --git a/kernel/drivers/char/misc.c b/kernel/drivers/char/misc.c
index 9fd5a91..8069b36 100644 (file)
--- a/kernel/drivers/char/misc.c
+++ b/kernel/drivers/char/misc.c
@@ -117,14 +117,14 @@ static int misc_open(struct inode * inode, struct file * file)
        const struct file_operations *new_fops = NULL;
 
        mutex_lock(&misc_mtx);
-       
+
        list_for_each_entry(c, &misc_list, list) {
                if (c->minor == minor) {
-                       new_fops = fops_get(c->fops);           
+                       new_fops = fops_get(c->fops);
                        break;
                }
        }
-               
+
        if (!new_fops) {
                mutex_unlock(&misc_mtx);
                request_module("char-major-%d-%d", MISC_MAJOR, minor);
@@ -167,7 +167,7 @@ static const struct file_operations misc_fops = {
 /**
  *     misc_register   -       register a miscellaneous device
  *     @misc: device structure
- *     
+ *
  *     Register a miscellaneous device with the kernel. If the minor
  *     number is set to %MISC_DYNAMIC_MINOR a minor number is assigned
  *     and placed in the minor field of the structure. For other cases
@@ -181,17 +181,18 @@ static const struct file_operations misc_fops = {
  *     A zero is returned on success and a negative errno code for
  *     failure.
  */
- 
+
 int misc_register(struct miscdevice * misc)
 {
        dev_t dev;
        int err = 0;
+       bool is_dynamic = (misc->minor == MISC_DYNAMIC_MINOR);
 
        INIT_LIST_HEAD(&misc->list);
 
        mutex_lock(&misc_mtx);
 
-       if (misc->minor == MISC_DYNAMIC_MINOR) {
+       if (is_dynamic) {
                int i = find_first_zero_bit(misc_minors, DYNAMIC_MINORS);
                if (i >= DYNAMIC_MINORS) {
                        err = -EBUSY;
@@ -216,9 +217,13 @@ int misc_register(struct miscdevice * misc)
                device_create_with_groups(misc_class, misc->parent, dev,
                                          misc, misc->groups, "%s", misc->name);
        if (IS_ERR(misc->this_device)) {
-               int i = DYNAMIC_MINORS - misc->minor - 1;
-               if (i < DYNAMIC_MINORS && i >= 0)
-                       clear_bit(i, misc_minors);
+               if (is_dynamic) {
+                       int i = DYNAMIC_MINORS - misc->minor - 1;
+
+                       if (i < DYNAMIC_MINORS && i >= 0)
+                               clear_bit(i, misc_minors);
+                       misc->minor = MISC_DYNAMIC_MINOR;
+               }
                err = PTR_ERR(misc->this_device);
                goto out;
        }
@@ -238,17 +243,15 @@ int misc_register(struct miscdevice * misc)
  *     @misc: device to unregister
  *
  *     Unregister a miscellaneous device that was previously
- *     successfully registered with misc_register(). Success
- *     is indicated by a zero return, a negative errno code
- *     indicates an error.
+ *     successfully registered with misc_register().
  */
 
-int misc_deregister(struct miscdevice *misc)
+void misc_deregister(struct miscdevice *misc)
 {
        int i = DYNAMIC_MINORS - misc->minor - 1;
 
        if (WARN_ON(list_empty(&misc->list)))
-               return -EINVAL;
+               return;
 
        mutex_lock(&misc_mtx);
        list_del(&misc->list);
@@ -256,7 +259,6 @@ int misc_deregister(struct miscdevice *misc)
        if (i < DYNAMIC_MINORS && i >= 0)
                clear_bit(i, misc_minors);
        mutex_unlock(&misc_mtx);
-       return 0;
 }
 
 EXPORT_SYMBOL(misc_register);
@@ -276,10 +278,9 @@ static char *misc_devnode(struct device *dev, umode_t *mode)
 static int __init misc_init(void)
 {
        int err;
+       struct proc_dir_entry *ret;
 
-#ifdef CONFIG_PROC_FS
-       proc_create("misc", 0, NULL, &misc_proc_fops);
-#endif
+       ret = proc_create("misc", 0, NULL, &misc_proc_fops);
        misc_class = class_create(THIS_MODULE, "misc");
        err = PTR_ERR(misc_class);
        if (IS_ERR(misc_class))
@@ -295,7 +296,8 @@ fail_printk:
        printk("unable to get major %d for misc devices\n", MISC_MAJOR);
        class_destroy(misc_class);
 fail_remove:
-       remove_proc_entry("misc", NULL);
+       if (ret)
+               remove_proc_entry("misc", NULL);
        return err;
 }
 subsys_initcall(misc_init);