Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
---
PoC patch.
v4:
- New in the series.
drivers/char/misc.c | 7 +++++++
include/linux/miscdevice.h | 3 +++
2 files changed, 10 insertions(+)
diff --git a/drivers/char/misc.c b/drivers/char/misc.c
index 726516fb0a3b..fcbbb0b1af35 100644
--- a/drivers/char/misc.c
+++ b/drivers/char/misc.c
@@ -159,6 +159,13 @@ static int misc_open(struct inode *inode, struct file *file)
err = 0;
replace_fops(file, new_fops);
+
+ if (c->rp && c->rops) {
+ err = revocable_replace_fops(file, c->rp, c->rops);
+ if (err)
+ goto fail;
+ }
+
if (file->f_op->open)
err = file->f_op->open(inode, file);
fail:
diff --git a/include/linux/miscdevice.h b/include/linux/miscdevice.h
index 7d0aa718499c..00f5c878266a 100644
--- a/include/linux/miscdevice.h
+++ b/include/linux/miscdevice.h
@@ -5,6 +5,7 @@
#include <linux/list.h>
#include <linux/types.h>
#include <linux/device.h>
+#include <linux/revocable.h>
/*
* These allocations are managed by device@lanana.org. If you need
@@ -92,6 +93,8 @@ struct miscdevice {
const struct attribute_group **groups;
const char *nodename;
umode_t mode;
+ struct revocable_provider *rp;
+ const struct revocable_operations *rops;
};
extern int misc_register(struct miscdevice *misc);
--
2.51.0.534.gc79095c0ca-goog