media: Set file->private_data in v4l2_fh_add()

All the drivers that use v4l2_fh and call v4l2_fh_add() manually store a
pointer to the v4l2_fh instance in file->private_data in their video
device .open() file operation handler. Move the code to the
v4l2_fh_add() 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 open;
type ret;
@@
ret open(..., struct file *filp, ...)
{
	<...
-	filp->private_data = fh;
	...
-	v4l2_fh_add(fh);
+	v4l2_fh_add(fh, filp);
	...>
}

@@
expression fh;
identifier filp;
identifier open;
type ret;
@@
ret open(..., struct file *filp, ...)
{
	<...
-	v4l2_fh_add(fh);
+	v4l2_fh_add(fh, filp);
	...
-	filp->private_data = fh;
	...>
}

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_add() prototype set file->private_data, and to
include/media/v4l2-fh.h to update the v4l2_fh_add() function prototype
and its documentation.

Additionally, white space issues have been fixed manually in
drivers/media/platform/nvidia/tegra-vde/v4l2.c,
drivers/media/platform/rockchip/rkvdec/rkvdec.c,
drivers/media/v4l2-core/v4l2-fh.c and
drivers/staging/most/video/video.c.

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

61 files changed, 91 insertions, 146 deletions

diff --git a/Documentation/driver-api/media/v4l2-fh.rst b/Documentation/driver-api/media/v4l2-fh.rst
index 2c87b74578d9..a7393067f5db 100644
--- a/Documentation/driver-api/media/v4l2-fh.rst
+++ b/Documentation/driver-api/media/v4l2-fh.rst
@@ -11,25 +11,22 @@ data that is used by the V4L2 framework.
 	since it is also used to implement priority handling
 	(:ref:`VIDIOC_G_PRIORITY`).
 
-The users of :c:type:`v4l2_fh` (in the V4L2 framework, not the driver) know
-whether a driver uses :c:type:`v4l2_fh` as its ``file->private_data`` pointer
-by testing the ``V4L2_FL_USES_V4L2_FH`` bit in :c:type:`video_device`->flags.
-This bit is set whenever :c:func:`v4l2_fh_init` is called.
-
-struct v4l2_fh is allocated as a part of the driver's own file handle
-structure and ``file->private_data`` is set to it in the driver's ``open()``
-function by the driver. The :c:type:`v4l2_fh` file handle can be retrieved
-from the :c:type:`file` using :c:func:`file_to_v4l2_fh`. Drivers must not
-access ``file->private_data`` directly.
-
-In many cases the struct v4l2_fh will be embedded in a larger
-structure. In that case you should call:
-
-#) :c:func:`v4l2_fh_init` and :c:func:`v4l2_fh_add` in ``open()``
-#) :c:func:`v4l2_fh_del` and :c:func:`v4l2_fh_exit` in ``release()``
-
-Drivers can extract their own file handle structure by using the container_of
-macro.
+struct v4l2_fh is allocated in the driver's ``open()`` file operation handler.
+It is typically embedded in a larger driver-specific structure. The
+:c:type:`v4l2_fh` must be initialized with a call to :c:func:`v4l2_fh_init`,
+and added to the video device with :c:func:`v4l2_fh_add`. This associates the
+:c:type:`v4l2_fh` with the :c:type:`file` by setting ``file->private_data`` to
+point to the :c:type:`v4l2_fh`.
+
+Similarly, the struct v4l2_fh is freed in the driver's ``release()`` file
+operation handler. It must be removed from the video device with
+:c:func:`v4l2_fh_del` and cleaned up with :c:func:`v4l2_fh_exit` before being
+freed.
+
+Drivers must not access ``file->private_data`` directly. They can retrieve the
+:c:type:`v4l2_fh` associated with a :c:type:`file` by calling
+:c:func:`file_to_v4l2_fh`. Drivers can extract their own file handle structure
+by using the container_of macro.
 
 Example:
 
@@ -58,8 +55,7 @@ Example:
 
 		...
 
-		file->private_data = &my_fh->fh;
-		v4l2_fh_add(&my_fh->fh);
+		v4l2_fh_add(&my_fh->fh, file);
 		return 0;
 	}
 
@@ -84,7 +80,7 @@ Below is a short description of the :c:type:`v4l2_fh` functions used:
   :c:type:`v4l2_file_operations`->open() handler.
 
 :c:func:`v4l2_fh_add <v4l2_fh_add>`
-(:c:type:`fh <v4l2_fh>`)
+(:c:type:`fh <v4l2_fh>`, struct file \*filp)
 
 - Add a :c:type:`v4l2_fh` to :c:type:`video_device` file handle list.
   Must be called once the file handle is completely initialized.
@@ -138,6 +134,12 @@ associated device node:
 
 - Same, but it calls v4l2_fh_is_singular with filp->private_data.
 
+.. note::
+        The V4L2 framework knows whether a driver uses :c:type:`v4l2_fh` as its
+        ``file->private_data`` pointer by testing the ``V4L2_FL_USES_V4L2_FH``
+        bit in :c:type:`video_device`->flags. This bit is set whenever
+        :c:func:`v4l2_fh_init` is called.
+
 
 V4L2 fh functions and data structures
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
diff --git a/Documentation/translations/zh_CN/video4linux/v4l2-framework.txt b/Documentation/translations/zh_CN/video4linux/v4l2-framework.txt
index a9eb62fa1531..2d38ae17d940 100644
--- a/Documentation/translations/zh_CN/video4linux/v4l2-framework.txt
+++ b/Documentation/translations/zh_CN/video4linux/v4l2-framework.txt
@@ -812,8 +812,7 @@ int my_open(struct file *file)
 
 	...
 
-	file->private_data = &my_fh->fh;
-	v4l2_fh_add(&my_fh->fh);
+	v4l2_fh_add(&my_fh->fh, file);
 	return 0;
 }
 
@@ -836,7 +835,7 @@ void v4l2_fh_init(struct v4l2_fh *fh, struct video_device *vdev)
   初始化文件句柄。这*必须*在驱动的 v4l2_file_operations->open()
   函数中执行。
 
-void v4l2_fh_add(struct v4l2_fh *fh)
+void v4l2_fh_add(struct v4l2_fh *fh, struct file *filp)
 
   添加一个 v4l2_fh 到 video_device 文件句柄列表。一旦文件句柄
   初始化完成就必须调用。
diff --git a/drivers/media/pci/cx18/cx18-fileops.c b/drivers/media/pci/cx18/cx18-fileops.c
index 89e38b303630..f90b547f5d67 100644
--- a/drivers/media/pci/cx18/cx18-fileops.c
+++ b/drivers/media/pci/cx18/cx18-fileops.c
@@ -743,8 +743,7 @@ static int cx18_serialized_open(struct cx18_stream *s, struct file *filp)
 	item->type = s->type;
 
 	item->open_id = cx->open_id++;
-	filp->private_data = &item->fh;
-	v4l2_fh_add(&item->fh);
+	v4l2_fh_add(&item->fh, filp);
 
 	if (item->type == CX18_ENC_STREAM_TYPE_RAD &&
 			v4l2_fh_is_singular_file(filp)) {
diff --git a/drivers/media/pci/ivtv/ivtv-fileops.c b/drivers/media/pci/ivtv/ivtv-fileops.c
index 67964a3c382c..aa5f5f16427c 100644
--- a/drivers/media/pci/ivtv/ivtv-fileops.c
+++ b/drivers/media/pci/ivtv/ivtv-fileops.c
@@ -998,9 +998,7 @@ static int ivtv_open(struct file *filp)
 	v4l2_fh_init(&item->fh, &s->vdev);
 	item->itv = itv;
 	item->type = s->type;
-
-	filp->private_data = &item->fh;
-	v4l2_fh_add(&item->fh);
+	v4l2_fh_add(&item->fh, filp);
 
 	if (item->type == IVTV_ENC_STREAM_TYPE_RAD &&
 			v4l2_fh_is_singular_file(filp)) {
diff --git a/drivers/media/pci/saa7164/saa7164-encoder.c b/drivers/media/pci/saa7164/saa7164-encoder.c
index 296f50b6b8d3..e6e353a251cf 100644
--- a/drivers/media/pci/saa7164/saa7164-encoder.c
+++ b/drivers/media/pci/saa7164/saa7164-encoder.c
@@ -725,8 +725,7 @@ static int fops_open(struct file *file)
 
 	fh->port = port;
 	v4l2_fh_init(&fh->fh, video_devdata(file));
-	v4l2_fh_add(&fh->fh);
-	file->private_data = &fh->fh;
+	v4l2_fh_add(&fh->fh, file);
 
 	return 0;
 }
diff --git a/drivers/media/pci/saa7164/saa7164-vbi.c b/drivers/media/pci/saa7164/saa7164-vbi.c
index a7e398f30472..181442fcb43b 100644
--- a/drivers/media/pci/saa7164/saa7164-vbi.c
+++ b/drivers/media/pci/saa7164/saa7164-vbi.c
@@ -428,8 +428,7 @@ static int fops_open(struct file *file)
 
 	fh->port = port;
 	v4l2_fh_init(&fh->fh, video_devdata(file));
-	v4l2_fh_add(&fh->fh);
-	file->private_data = &fh->fh;
+	v4l2_fh_add(&fh->fh, file);
 
 	return 0;
 }
diff --git a/drivers/media/platform/allegro-dvt/allegro-core.c b/drivers/media/platform/allegro-dvt/allegro-core.c
index 74977f3ae484..8c30f3cd4fc5 100644
--- a/drivers/media/platform/allegro-dvt/allegro-core.c
+++ b/drivers/media/platform/allegro-dvt/allegro-core.c
@@ -3219,8 +3219,7 @@ static int allegro_open(struct file *file)
 	}
 
 	list_add(&channel->list, &dev->channels);
-	file->private_data = &channel->fh;
-	v4l2_fh_add(&channel->fh);
+	v4l2_fh_add(&channel->fh, file);
 
 	allegro_channel_adjust(channel);
 
diff --git a/drivers/media/platform/amlogic/meson-ge2d/ge2d.c b/drivers/media/platform/amlogic/meson-ge2d/ge2d.c
index c7df29a2d820..d36891b546bc 100644
--- a/drivers/media/platform/amlogic/meson-ge2d/ge2d.c
+++ b/drivers/media/platform/amlogic/meson-ge2d/ge2d.c
@@ -860,8 +860,7 @@ static int ge2d_open(struct file *file)
 		return ret;
 	}
 	v4l2_fh_init(&ctx->fh, video_devdata(file));
-	file->private_data = &ctx->fh;
-	v4l2_fh_add(&ctx->fh);
+	v4l2_fh_add(&ctx->fh, file);
 
 	ge2d_setup_ctrls(ctx);
 
diff --git a/drivers/media/platform/amphion/vpu_v4l2.c b/drivers/media/platform/amphion/vpu_v4l2.c
index 57ca6262bb04..e13bfe09af1b 100644
--- a/drivers/media/platform/amphion/vpu_v4l2.c
+++ b/drivers/media/platform/amphion/vpu_v4l2.c
@@ -760,7 +760,7 @@ int vpu_v4l2_open(struct file *file, struct vpu_inst *inst)
 	inst->min_buffer_cap = 2;
 	inst->min_buffer_out = 2;
 	v4l2_fh_init(&inst->fh, func->vfd);
-	v4l2_fh_add(&inst->fh);
+	v4l2_fh_add(&inst->fh, file);
 
 	ret = call_vop(inst, ctrl_init);
 	if (ret)
@@ -774,7 +774,6 @@ int vpu_v4l2_open(struct file *file, struct vpu_inst *inst)
 	}
 
 	inst->fh.ctrl_handler = &inst->ctrl_handler;
-	file->private_data = &inst->fh;
 	inst->state = VPU_CODEC_STATE_DEINIT;
 	inst->workqueue = alloc_ordered_workqueue("vpu_inst", WQ_MEM_RECLAIM);
 	if (inst->workqueue) {
diff --git a/drivers/media/platform/chips-media/coda/coda-common.c b/drivers/media/platform/chips-media/coda/coda-common.c
index 459b59149390..7d874fd502b8 100644
--- a/drivers/media/platform/chips-media/coda/coda-common.c
+++ b/drivers/media/platform/chips-media/coda/coda-common.c
@@ -2642,8 +2642,7 @@ static int coda_open(struct file *file)
 	if (ctx->ops->seq_end_work)
 		INIT_WORK(&ctx->seq_end_work, ctx->ops->seq_end_work);
 	v4l2_fh_init(&ctx->fh, video_devdata(file));
-	file->private_data = &ctx->fh;
-	v4l2_fh_add(&ctx->fh);
+	v4l2_fh_add(&ctx->fh, file);
 	ctx->dev = dev;
 	ctx->idx = idx;
 
diff --git a/drivers/media/platform/chips-media/wave5/wave5-vpu-dec.c b/drivers/media/platform/chips-media/wave5/wave5-vpu-dec.c
index f3188d720ed3..88eb933a5144 100644
--- a/drivers/media/platform/chips-media/wave5/wave5-vpu-dec.c
+++ b/drivers/media/platform/chips-media/wave5/wave5-vpu-dec.c
@@ -1761,8 +1761,7 @@ static int wave5_vpu_open_dec(struct file *filp)
 		return -ENOMEM;
 
 	v4l2_fh_init(&inst->v4l2_fh, vdev);
-	filp->private_data = &inst->v4l2_fh;
-	v4l2_fh_add(&inst->v4l2_fh);
+	v4l2_fh_add(&inst->v4l2_fh, filp);
 
 	INIT_LIST_HEAD(&inst->list);
 
diff --git a/drivers/media/platform/chips-media/wave5/wave5-vpu-enc.c b/drivers/media/platform/chips-media/wave5/wave5-vpu-enc.c
index b69a1206fa12..322c1498758a 100644
--- a/drivers/media/platform/chips-media/wave5/wave5-vpu-enc.c
+++ b/drivers/media/platform/chips-media/wave5/wave5-vpu-enc.c
@@ -1587,8 +1587,7 @@ static int wave5_vpu_open_enc(struct file *filp)
 		return -ENOMEM;
 
 	v4l2_fh_init(&inst->v4l2_fh, vdev);
-	filp->private_data = &inst->v4l2_fh;
-	v4l2_fh_add(&inst->v4l2_fh);
+	v4l2_fh_add(&inst->v4l2_fh, filp);
 
 	INIT_LIST_HEAD(&inst->list);
 
diff --git a/drivers/media/platform/imagination/e5010-jpeg-enc.c b/drivers/media/platform/imagination/e5010-jpeg-enc.c
index 295461325862..1da00ff4b1e3 100644
--- a/drivers/media/platform/imagination/e5010-jpeg-enc.c
+++ b/drivers/media/platform/imagination/e5010-jpeg-enc.c
@@ -742,8 +742,7 @@ static int e5010_open(struct file *file)
 	}
 
 	v4l2_fh_init(&ctx->fh, vdev);
-	file->private_data = &ctx->fh;
-	v4l2_fh_add(&ctx->fh);
+	v4l2_fh_add(&ctx->fh, file);
 
 	ctx->e5010 = e5010;
 	ctx->fh.m2m_ctx = v4l2_m2m_ctx_init(e5010->m2m_dev, ctx, queue_init);
diff --git a/drivers/media/platform/m2m-deinterlace.c b/drivers/media/platform/m2m-deinterlace.c
index 1812c07837ad..a343dffd19f0 100644
--- a/drivers/media/platform/m2m-deinterlace.c
+++ b/drivers/media/platform/m2m-deinterlace.c
@@ -847,7 +847,6 @@ static int deinterlace_open(struct file *file)
 		return -ENOMEM;
 
 	v4l2_fh_init(&ctx->fh, video_devdata(file));
-	file->private_data = &ctx->fh;
 	ctx->dev = pcdev;
 
 	ctx->fh.m2m_ctx = v4l2_m2m_ctx_init(pcdev->m2m_dev, ctx, &queue_init);
@@ -866,7 +865,7 @@ static int deinterlace_open(struct file *file)
 	}
 
 	ctx->colorspace = V4L2_COLORSPACE_REC709;
-	v4l2_fh_add(&ctx->fh);
+	v4l2_fh_add(&ctx->fh, file);
 
 	dprintk(pcdev, "Created instance %p, m2m_ctx: %p\n",
 		ctx, ctx->fh.m2m_ctx);
diff --git a/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c b/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c
index 3a7a6eb53d89..5178a1b170fe 100644
--- a/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c
+++ b/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c
@@ -1176,8 +1176,7 @@ static int mtk_jpeg_open(struct file *file)
 	INIT_LIST_HEAD(&ctx->dst_done_queue);
 	spin_lock_init(&ctx->done_queue_lock);
 	v4l2_fh_init(&ctx->fh, vfd);
-	file->private_data = &ctx->fh;
-	v4l2_fh_add(&ctx->fh);
+	v4l2_fh_add(&ctx->fh, file);
 
 	ctx->jpeg = jpeg;
 	ctx->fh.m2m_ctx = v4l2_m2m_ctx_init(jpeg->m2m_dev, ctx,
diff --git a/drivers/media/platform/mediatek/mdp/mtk_mdp_m2m.c b/drivers/media/platform/mediatek/mdp/mtk_mdp_m2m.c
index 2d894b5bfaa7..7a1a8e51dbca 100644
--- a/drivers/media/platform/mediatek/mdp/mtk_mdp_m2m.c
+++ b/drivers/media/platform/mediatek/mdp/mtk_mdp_m2m.c
@@ -1070,14 +1070,13 @@ static int mtk_mdp_m2m_open(struct file *file)
 	mutex_init(&ctx->slock);
 	ctx->id = mdp->id_counter++;
 	v4l2_fh_init(&ctx->fh, vfd);
-	file->private_data = &ctx->fh;
 	ret = mtk_mdp_ctrls_create(ctx);
 	if (ret)
 		goto error_ctrls;
 
 	/* Use separate control handler per file handle */
 	ctx->fh.ctrl_handler = &ctx->ctrl_handler;
-	v4l2_fh_add(&ctx->fh);
+	v4l2_fh_add(&ctx->fh, file);
 	INIT_LIST_HEAD(&ctx->list);
 
 	ctx->mdp_dev = mdp;
diff --git a/drivers/media/platform/mediatek/mdp3/mtk-mdp3-m2m.c b/drivers/media/platform/mediatek/mdp3/mtk-mdp3-m2m.c
index 886ff25c70eb..847d6b310e74 100644
--- a/drivers/media/platform/mediatek/mdp3/mtk-mdp3-m2m.c
+++ b/drivers/media/platform/mediatek/mdp3/mtk-mdp3-m2m.c
@@ -590,14 +590,13 @@ static int mdp_m2m_open(struct file *file)
 	ctx->mdp_dev = mdp;
 
 	v4l2_fh_init(&ctx->fh, vdev);
-	file->private_data = &ctx->fh;
 	ret = mdp_m2m_ctrls_create(ctx);
 	if (ret)
 		goto err_exit_fh;
 
 	/* Use separate control handler per file handle */
 	ctx->fh.ctrl_handler = &ctx->ctrl_handler;
-	v4l2_fh_add(&ctx->fh);
+	v4l2_fh_add(&ctx->fh, file);
 
 	mutex_init(&ctx->ctx_lock);
 	ctx->m2m_ctx = v4l2_m2m_ctx_init(mdp->m2m_dev, ctx, mdp_m2m_queue_init);
diff --git a/drivers/media/platform/mediatek/vcodec/decoder/mtk_vcodec_dec_drv.c b/drivers/media/platform/mediatek/vcodec/decoder/mtk_vcodec_dec_drv.c
index 18801883c31a..952a77c383bd 100644
--- a/drivers/media/platform/mediatek/vcodec/decoder/mtk_vcodec_dec_drv.c
+++ b/drivers/media/platform/mediatek/vcodec/decoder/mtk_vcodec_dec_drv.c
@@ -206,8 +206,7 @@ static int fops_vcodec_open(struct file *file)
 	mutex_lock(&dev->dev_mutex);
 	ctx->id = dev->id_counter++;
 	v4l2_fh_init(&ctx->fh, video_devdata(file));
-	file->private_data = &ctx->fh;
-	v4l2_fh_add(&ctx->fh);
+	v4l2_fh_add(&ctx->fh, file);
 	INIT_LIST_HEAD(&ctx->list);
 	ctx->dev = dev;
 	if (ctx->dev->vdec_pdata->is_subdev_supported) {
diff --git a/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drv.c b/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drv.c
index e26a6c3ffa0c..9cacb6cbcf28 100644
--- a/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drv.c
+++ b/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_drv.c
@@ -129,8 +129,7 @@ static int fops_vcodec_open(struct file *file)
 	 */
 	ctx->id = dev->id_counter++;
 	v4l2_fh_init(&ctx->fh, video_devdata(file));
-	file->private_data = &ctx->fh;
-	v4l2_fh_add(&ctx->fh);
+	v4l2_fh_add(&ctx->fh, file);
 	INIT_LIST_HEAD(&ctx->list);
 	ctx->dev = dev;
 	init_waitqueue_head(&ctx->queue[0]);
diff --git a/drivers/media/platform/nvidia/tegra-vde/v4l2.c b/drivers/media/platform/nvidia/tegra-vde/v4l2.c
index 393dc3f07d5c..688b776b3010 100644
--- a/drivers/media/platform/nvidia/tegra-vde/v4l2.c
+++ b/drivers/media/platform/nvidia/tegra-vde/v4l2.c
@@ -832,8 +832,7 @@ static int tegra_open(struct file *file)
 		goto free_ctrls;
 	}
 
-	file->private_data = &ctx->fh;
-	v4l2_fh_add(&ctx->fh);
+	v4l2_fh_add(&ctx->fh, file);
 
 	tegra_reset_coded_fmt(ctx);
 	tegra_try_coded_fmt(file, &ctx->fh, &ctx->coded_fmt);
diff --git a/drivers/media/platform/nxp/dw100/dw100.c b/drivers/media/platform/nxp/dw100/dw100.c
index 2460f09a6813..2bd30910ddf9 100644
--- a/drivers/media/platform/nxp/dw100/dw100.c
+++ b/drivers/media/platform/nxp/dw100/dw100.c
@@ -607,7 +607,6 @@ static int dw100_open(struct file *file)
 
 	mutex_init(&ctx->vq_mutex);
 	v4l2_fh_init(&ctx->fh, video_devdata(file));
-	file->private_data = &ctx->fh;
 	ctx->dw_dev = dw_dev;
 
 	ctx->q_data[DW100_QUEUE_SRC].fmt = &formats[0];
@@ -651,7 +650,7 @@ static int dw100_open(struct file *file)
 		goto err;
 	}
 
-	v4l2_fh_add(&ctx->fh);
+	v4l2_fh_add(&ctx->fh, file);
 
 	return 0;
 
diff --git a/drivers/media/platform/nxp/imx-jpeg/mxc-jpeg.c b/drivers/media/platform/nxp/imx-jpeg/mxc-jpeg.c
index 8eef7ebd0428.