From: Rafael J. Wysocki <rjw@sisk.pl>
Make it possible to unregister a misc device object in a safe way
during a suspend/resume cycle.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
---
drivers/char/misc.c | 13 +++++++++----
include/linux/miscdevice.h | 10 +++++++++-
2 files changed, 18 insertions(+), 5 deletions(-)
Index: linux-2.6.24-rc8-mm1/include/linux/miscdevice.h
===================================================================
--- linux-2.6.24-rc8-mm1.orig/include/linux/miscdevice.h
+++ linux-2.6.24-rc8-mm1/include/linux/miscdevice.h
@@ -43,7 +43,15 @@ struct miscdevice {
};
extern int misc_register(struct miscdevice * misc);
-extern int misc_deregister(struct miscdevice * misc);
+extern int __misc_deregister(struct miscdevice *misc, bool suspended);
+static inline int misc_deregister(struct miscdevice *misc)
+{
+ return __misc_deregister(misc, false);
+}
+static inline int misc_deregister_suspended(struct miscdevice *misc)
+{
+ return __misc_deregister(misc, true);
+}
#define MODULE_ALIAS_MISCDEV(minor) \
MODULE_ALIAS("char-major-" __stringify(MISC_MAJOR) \
Index: linux-2.6.24-rc8-mm1/drivers/char/misc.c
===================================================================
--- linux-2.6.24-rc8-mm1.orig/drivers/char/misc.c
+++ linux-2.6.24-rc8-mm1/drivers/char/misc.c
@@ -232,8 +232,9 @@ int misc_register(struct miscdevice * mi
}
/**
- * misc_deregister - unregister a miscellaneous device
+ * __misc_deregister - unregister a miscellaneous device
* @misc: device to unregister
+ * @suspended: to be set if the function is used during suspend/resume
*
* Unregister a miscellaneous device that was previously
* successfully registered with misc_register(). Success
@@ -241,7 +242,7 @@ int misc_register(struct miscdevice * mi
* indicates an error.
*/
-int misc_deregister(struct miscdevice * misc)
+int __misc_deregister(struct miscdevice *misc, bool suspended)
{
int i = misc->minor;
@@ -250,7 +251,11 @@ int misc_deregister(struct miscdevice *
mutex_lock(&misc_mtx);
list_del(&misc->list);
- device_destroy(misc_class, MKDEV(MISC_MAJOR, misc->minor));
+ if (suspended)
+ destroy_suspended_device(misc_class,
+ MKDEV(MISC_MAJOR, misc->minor));
+ else
+ device_destroy(misc_class, MKDEV(MISC_MAJOR, misc->minor));
if (i < DYNAMIC_MINORS && i>0) {
misc_minors[i>>3] &= ~(1 << (misc->minor & 7));
}
@@ -259,7 +264,7 @@ int misc_deregister(struct miscdevice *
}
EXPORT_SYMBOL(misc_register);
-EXPORT_SYMBOL(misc_deregister);
+EXPORT_SYMBOL(__misc_deregister);
static int __init misc_init(void)
{
--
