base: genlock: Remove genlock_release_lock and associated ioctl
Allowing a lock to be asynchronously released while a handle
was still active turned out to be too dangerous to use in a
multi-threaded environment and it served no pratical
purpose anyway. Handles now hold an attached lock until they
are destroyed.
CRs-fixed: 333141
Change-Id: Ic0dedbad8050ff01927ddb165c65a939bf297c10
Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
diff --git a/Documentation/genlock.txt b/Documentation/genlock.txt
index d3a44e2..6f24a76 100644
--- a/Documentation/genlock.txt
+++ b/Documentation/genlock.txt
@@ -82,15 +82,13 @@
Release a handle.
* struct genlock * genlock_create_lock(struct genlock_handle *)
-Create a new lock and attach it to the handle.
+Create a new lock and attach it to the handle. Once a lock is attached to a
+handle it stays attached until the handle is destroyed.
* struct genlock * genlock_attach_lock(struct genlock_handle *handle, int fd)
Given a valid file descriptor, get the lock associated with it and attach it to
the handle.
-* void genlock_release_lock(struct genlock_handle *)
-Release a lock attached to a handle.
-
* int genlock_lock(struct genlock_handle *, int op, int flags, u32 timeout)
Lock or unlock the lock attached to the handle. A zero timeout value will
be treated just like if the GENOCK_NOBLOCK flag is passed; if the lock
@@ -155,7 +153,4 @@
-EINVAL if a zero timeout is passed, or -ETIMEDOUT if the timeout expires.
* GENLOCK_IOC_RELEASE
-Use this to release an existing lock. This is useful if you wish to attach a
-different lock to the same handle. You do not need to call this under normal
-circumstances; when the handle is closed the reference to the lock is released.
-No data is passed from the user for this ioctl.
+This ioctl has been deprecated. Do not use.
diff --git a/drivers/base/genlock.c b/drivers/base/genlock.c
index 27717e0..1507915 100644
--- a/drivers/base/genlock.c
+++ b/drivers/base/genlock.c
@@ -496,12 +496,7 @@
return ret;
}
-/**
- * genlock_release_lock - Release a lock attached to a handle
- * @handle - Pointer to the handle holding the lock
- */
-
-void genlock_release_lock(struct genlock_handle *handle)
+static void genlock_release_lock(struct genlock_handle *handle)
{
unsigned long flags;
@@ -522,7 +517,6 @@
handle->lock = NULL;
handle->active = 0;
}
-EXPORT_SYMBOL(genlock_release_lock);
/*
* Release function called when all references to a handle are released
@@ -671,8 +665,13 @@
return genlock_wait(handle, param.timeout);
}
case GENLOCK_IOC_RELEASE: {
- genlock_release_lock(handle);
- return 0;
+ /*
+ * Return error - this ioctl has been deprecated.
+ * Locks should only be released when the handle is
+ * destroyed
+ */
+ GENLOCK_LOG_ERR("Deprecated RELEASE ioctl called\n");
+ return -EINVAL;
}
default:
GENLOCK_LOG_ERR("Invalid ioctl\n");
diff --git a/include/linux/genlock.h b/include/linux/genlock.h
index 2e9f9d6..9351a15 100644
--- a/include/linux/genlock.h
+++ b/include/linux/genlock.h
@@ -12,7 +12,7 @@
struct genlock *genlock_create_lock(struct genlock_handle *);
struct genlock *genlock_attach_lock(struct genlock_handle *, int fd);
int genlock_wait(struct genlock_handle *handle, u32 timeout);
-void genlock_release_lock(struct genlock_handle *);
+/* genlock_release_lock was deprecated */
int genlock_lock(struct genlock_handle *handle, int op, int flags,
u32 timeout);
#endif
@@ -39,6 +39,8 @@
struct genlock_lock)
#define GENLOCK_IOC_LOCK _IOW(GENLOCK_IOC_MAGIC, 3, \
struct genlock_lock)
+
+/* Deprecated */
#define GENLOCK_IOC_RELEASE _IO(GENLOCK_IOC_MAGIC, 4)
#define GENLOCK_IOC_WAIT _IOW(GENLOCK_IOC_MAGIC, 5, \
struct genlock_lock)