media: Reset file->private_data to NULL in v4l2_fh_del()

Multiple drivers that use v4l2_fh and call v4l2_fh_del() manually reset
the file->private_data pointer to NULL in their video device .release()
file operation handler. Move the code to the v4l2_fh_del() function to
avoid direct access to file->private_data in drivers. This requires
adding a file pointer argument to the function.

Changes to drivers have been generated with the following coccinelle
semantic patch:

@@
expression fh;
identifier filp;
identifier release;
type ret;
@@
ret release(..., struct file *filp, ...)
{
	<...
-	filp->private_data = NULL;
	...
-	v4l2_fh_del(fh);
+	v4l2_fh_del(fh, filp);
	...>
}

@@
expression fh;
identifier filp;
identifier release;
type ret;
@@
ret release(..., struct file *filp, ...)
{
	<...
-	v4l2_fh_del(fh);
+	v4l2_fh_del(fh, filp);
	...
-	filp->private_data = NULL;
	...>
}

@@
expression fh;
identifier filp;
identifier release;
type ret;
@@
ret release(..., struct file *filp, ...)
{
	<...
-	v4l2_fh_del(fh);
+	v4l2_fh_del(fh, filp);
	...>
}

Manual changes have been applied to Documentation/ to update the usage
patterns, to drivers/media/v4l2-core/v4l2-fh.c to update the
v4l2_fh_del() prototype and reset file->private_data, and to
include/media/v4l2-fh.h to update the v4l2_fh_del() function prototype
and its documentation.

Additionally, white space issues have been fixed manually in
drivers/usb/gadget/function/uvc_v4l2.c

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>

3 files changed, 3 insertions, 3 deletions

diff --git a/drivers/media/test-drivers/vicodec/vicodec-core.c b/drivers/media/test-drivers/vicodec/vicodec-core.c
index f20d9d9643f5..c340fd226040 100644
--- a/drivers/media/test-drivers/vicodec/vicodec-core.c
+++ b/drivers/media/test-drivers/vicodec/vicodec-core.c
@@ -1946,7 +1946,7 @@ static int vicodec_release(struct file *file)
 	mutex_lock(vfd->lock);
 	v4l2_m2m_ctx_release(ctx->fh.m2m_ctx);
 	mutex_unlock(vfd->lock);
-	v4l2_fh_del(&ctx->fh);
+	v4l2_fh_del(&ctx->fh, file);
 	v4l2_fh_exit(&ctx->fh);
 	v4l2_ctrl_handler_free(&ctx->hdl);
 	kvfree(ctx->state.compressed_frame);
diff --git a/drivers/media/test-drivers/vim2m.c b/drivers/media/test-drivers/vim2m.c
index 24574025f58f..d0e760118c82 100644
--- a/drivers/media/test-drivers/vim2m.c
+++ b/drivers/media/test-drivers/vim2m.c
@@ -1450,7 +1450,7 @@ static int vim2m_release(struct file *file)
 
 	dprintk(dev, 1, "Releasing instance %p\n", ctx);
 
-	v4l2_fh_del(&ctx->fh);
+	v4l2_fh_del(&ctx->fh, file);
 	v4l2_fh_exit(&ctx->fh);
 	v4l2_ctrl_handler_free(&ctx->hdl);
 	mutex_lock(&dev->dev_mutex);
diff --git a/drivers/media/test-drivers/visl/visl-core.c b/drivers/media/test-drivers/visl/visl-core.c
index 0f43ec23f40b..26c6c6835f79 100644
--- a/drivers/media/test-drivers/visl/visl-core.c
+++ b/drivers/media/test-drivers/visl/visl-core.c
@@ -389,7 +389,7 @@ static int visl_release(struct file *file)
 	dprintk(dev, "Releasing instance %p\n", ctx);
 
 	tpg_free(&ctx->tpg);
-	v4l2_fh_del(&ctx->fh);
+	v4l2_fh_del(&ctx->fh, file);
 	v4l2_fh_exit(&ctx->fh);
 	v4l2_ctrl_handler_free(&ctx->hdl);
 	mutex_lock(&dev->dev_mutex);