kbuild: rust: keep Rust objects out of Clang LTO with inline helpersgrafted

Under `CONFIG_LTO_CLANG` + `CONFIG_RUST_INLINE_HELPERS`, one may hit
`objtool` errors such as:

    vmlinux.o: error: objtool: _R..._3Gsp4boot+0xd6a:
    can't find jump dest instruction at .text._R..._3Gsp4boot+0x1dfd

The reason is that in such builds, the Clang invocation that compiles
the combined Rust plus helpers bitcode emits LLVM bitcode (again) --
the final code generation happens in the linker's LTO step, which the
`-mllvm` trap options passed to Clang do not reach.

This, in turn, means that unreachable traps are missing, and the
impossible paths do not merely fallthrough to the next symbol, but past
the end of their own section, since LTO builds place each function in
its own section.

Thus filter `CC_FLAGS_LTO` out of the Clang invocation, so that it always
emits machine code directly, with the traps in place.

Assisted-by: LLM
Cc: Gary Guo <gary@garyguo.net>
Cc: Boqun Feng <boqun@kernel.org>
Cc: Alice Ryhl <aliceryhl@google.com>
Cc: Matthew Maurer <mmaurer@google.com>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Fixes: 3a2486cc1da5 ("kbuild: rust: provide an option to inline C helpers into Rust")
Acked-by: Gary Guo <gary@garyguo.net>
Link: https://patch.msgid.link/20260816133233.197500-2-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

1 files changed, 800 insertions, 0 deletions

diff --git a/include/media/v4l2-ioctl.h b/include/media/v4l2-ioctl.h
new file mode 100644
index 000000000..54c83b18d
--- /dev/null
+++ b/include/media/v4l2-ioctl.h
@@ -0,0 +1,800 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ *
+ *	V 4 L 2   D R I V E R   H E L P E R   A P I
+ *
+ * Moved from videodev2.h
+ *
+ *	Some commonly needed functions for drivers (v4l2-common.o module)
+ */
+#ifndef _V4L2_IOCTL_H
+#define _V4L2_IOCTL_H
+
+#include <linux/poll.h>
+#include <linux/fs.h>
+#include <linux/mutex.h>
+#include <linux/sched/signal.h>
+#include <linux/compiler.h> /* need __user */
+#include <linux/videodev2.h>
+
+struct v4l2_fh;
+
+/**
+ * struct v4l2_ioctl_ops - describe operations for each V4L2 ioctl
+ *
+ * @vidioc_querycap: pointer to the function that implements
+ *	:ref:`VIDIOC_QUERYCAP <vidioc_querycap>` ioctl
+ * @vidioc_enum_fmt_vid_cap: pointer to the function that implements
+ *	:ref:`VIDIOC_ENUM_FMT <vidioc_enum_fmt>` ioctl logic
+ *	for video capture in single and multi plane mode
+ * @vidioc_enum_fmt_vid_overlay: pointer to the function that implements
+ *	:ref:`VIDIOC_ENUM_FMT <vidioc_enum_fmt>` ioctl logic
+ *	for video overlay
+ * @vidioc_enum_fmt_vid_out: pointer to the function that implements
+ *	:ref:`VIDIOC_ENUM_FMT <vidioc_enum_fmt>` ioctl logic
+ *	for video output in single and multi plane mode
+ * @vidioc_enum_fmt_sdr_cap: pointer to the function that implements
+ *	:ref:`VIDIOC_ENUM_FMT <vidioc_enum_fmt>` ioctl logic
+ *	for Software Defined Radio capture
+ * @vidioc_enum_fmt_sdr_out: pointer to the function that implements
+ *	:ref:`VIDIOC_ENUM_FMT <vidioc_enum_fmt>` ioctl logic
+ *	for Software Defined Radio output
+ * @vidioc_enum_fmt_meta_cap: pointer to the function that implements
+ *	:ref:`VIDIOC_ENUM_FMT <vidioc_enum_fmt>` ioctl logic
+ *	for metadata capture
+ * @vidioc_enum_fmt_meta_out: pointer to the function that implements
+ *	:ref:`VIDIOC_ENUM_FMT <vidioc_enum_fmt>` ioctl logic
+ *	for metadata output
+ * @vidioc_g_fmt_vid_cap: pointer to the function that implements
+ *	:ref:`VIDIOC_G_FMT <vidioc_g_fmt>` ioctl logic for video capture
+ *	in single plane mode
+ * @vidioc_g_fmt_vid_overlay: pointer to the function that implements
+ *	:ref:`VIDIOC_G_FMT <vidioc_g_fmt>` ioctl logic for video overlay
+ * @vidioc_g_fmt_vid_out: pointer to the function that implements
+ *	:ref:`VIDIOC_G_FMT <vidioc_g_fmt>` ioctl logic for video out
+ *	in single plane mode
+ * @vidioc_g_fmt_vid_out_overlay: pointer to the function that implements
+ *	:ref:`VIDIOC_G_FMT <vidioc_g_fmt>` ioctl logic for video overlay output
+ * @vidioc_g_fmt_vbi_cap: pointer to the function that implements
+ *	:ref:`VIDIOC_G_FMT <vidioc_g_fmt>` ioctl logic for raw VBI capture
+ * @vidioc_g_fmt_vbi_out: pointer to the function that implements
+ *	:ref:`VIDIOC_G_FMT <vidioc_g_fmt>` ioctl logic for raw VBI output
+ * @vidioc_g_fmt_sliced_vbi_cap: pointer to the function that implements
+ *	:ref:`VIDIOC_G_FMT <vidioc_g_fmt>` ioctl logic for sliced VBI capture
+ * @vidioc_g_fmt_sliced_vbi_out: pointer to the function that implements
+ *	:ref:`VIDIOC_G_FMT <vidioc_g_fmt>` ioctl logic for sliced VBI output
+ * @vidioc_g_fmt_vid_cap_mplane: pointer to the function that implements
+ *	:ref:`VIDIOC_G_FMT <vidioc_g_fmt>` ioctl logic for video capture
+ *	in multiple plane mode
+ * @vidioc_g_fmt_vid_out_mplane: pointer to the function that implements
+ *	:ref:`VIDIOC_G_FMT <vidioc_g_fmt>` ioctl logic for video out
+ *	in multiplane plane mode
+ * @vidioc_g_fmt_sdr_cap: pointer to the function that implements
+ *	:ref:`VIDIOC_G_FMT <vidioc_g_fmt>` ioctl logic for Software Defined
+ *	Radio capture
+ * @vidioc_g_fmt_sdr_out: pointer to the function that implements
+ *	:ref:`VIDIOC_G_FMT <vidioc_g_fmt>` ioctl logic for Software Defined
+ *	Radio output
+ * @vidioc_g_fmt_meta_cap: pointer to the function that implements
+ *	:ref:`VIDIOC_G_FMT <vidioc_g_fmt>` ioctl logic for metadata capture
+ * @vidioc_g_fmt_meta_out: pointer to the function that implements
+ *	:ref:`VIDIOC_G_FMT <vidioc_g_fmt>` ioctl logic for metadata output
+ * @vidioc_s_fmt_vid_cap: pointer to the function that implements
+ *	:ref:`VIDIOC_S_FMT <vidioc_g_fmt>` ioctl logic for video capture
+ *	in single plane mode
+ * @vidioc_s_fmt_vid_overlay: pointer to the function that implements
+ *	:ref:`VIDIOC_S_FMT <vidioc_g_fmt>` ioctl logic for video overlay
+ * @vidioc_s_fmt_vid_out: pointer to the function that implements
+ *	:ref:`VIDIOC_S_FMT <vidioc_g_fmt>` ioctl logic for video out
+ *	in single plane mode
+ * @vidioc_s_fmt_vid_out_overlay: pointer to the function that implements
+ *	:ref:`VIDIOC_S_FMT <vidioc_g_fmt>` ioctl logic for video overlay output
+ * @vidioc_s_fmt_vbi_cap: pointer to the function that implements
+ *	:ref:`VIDIOC_S_FMT <vidioc_g_fmt>` ioctl logic for raw VBI capture
+ * @vidioc_s_fmt_vbi_out: pointer to the function that implements
+ *	:ref:`VIDIOC_S_FMT <vidioc_g_fmt>` ioctl logic for raw VBI output
+ * @vidioc_s_fmt_sliced_vbi_cap: pointer to the function that implements
+ *	:ref:`VIDIOC_S_FMT <vidioc_g_fmt>` ioctl logic for sliced VBI capture
+ * @vidioc_s_fmt_sliced_vbi_out: pointer to the function that implements
+ *	:ref:`VIDIOC_S_FMT <vidioc_g_fmt>` ioctl logic for sliced VBI output
+ * @vidioc_s_fmt_vid_cap_mplane: pointer to the function that implements
+ *	:ref:`VIDIOC_S_FMT <vidioc_g_fmt>` ioctl logic for video capture
+ *	in multiple plane mode
+ * @vidioc_s_fmt_vid_out_mplane: pointer to the function that implements
+ *	:ref:`VIDIOC_S_FMT <vidioc_g_fmt>` ioctl logic for video out
+ *	in multiplane plane mode
+ * @vidioc_s_fmt_sdr_cap: pointer to the function that implements
+ *	:ref:`VIDIOC_S_FMT <vidioc_g_fmt>` ioctl logic for Software Defined
+ *	Radio capture
+ * @vidioc_s_fmt_sdr_out: pointer to the function that implements
+ *	:ref:`VIDIOC_S_FMT <vidioc_g_fmt>` ioctl logic for Software Defined
+ *	Radio output
+ * @vidioc_s_fmt_meta_cap: pointer to the function that implements
+ *	:ref:`VIDIOC_S_FMT <vidioc_g_fmt>` ioctl logic for metadata capture
+ * @vidioc_s_fmt_meta_out: pointer to the function that implements
+ *	:ref:`VIDIOC_S_FMT <vidioc_g_fmt>` ioctl logic for metadata output
+ * @vidioc_try_fmt_vid_cap: pointer to the function that implements
+ *	:ref:`VIDIOC_TRY_FMT <vidioc_g_fmt>` ioctl logic for video capture
+ *	in single plane mode
+ * @vidioc_try_fmt_vid_overlay: pointer to the function that implements
+ *	:ref:`VIDIOC_TRY_FMT <vidioc_g_fmt>` ioctl logic for video overlay
+ * @vidioc_try_fmt_vid_out: pointer to the function that implements
+ *	:ref:`VIDIOC_TRY_FMT <vidioc_g_fmt>` ioctl logic for video out
+ *	in single plane mode
+ * @vidioc_try_fmt_vid_out_overlay: pointer to the function that implements
+ *	:ref:`VIDIOC_TRY_FMT <vidioc_g_fmt>` ioctl logic for video overlay
+ *	output
+ * @vidioc_try_fmt_vbi_cap: pointer to the function that implements
+ *	:ref:`VIDIOC_TRY_FMT <vidioc_g_fmt>` ioctl logic for raw VBI capture
+ * @vidioc_try_fmt_vbi_out: pointer to the function that implements
+ *	:ref:`VIDIOC_TRY_FMT <vidioc_g_fmt>` ioctl logic for raw VBI output
+ * @vidioc_try_fmt_sliced_vbi_cap: pointer to the function that implements
+ *	:ref:`VIDIOC_TRY_FMT <vidioc_g_fmt>` ioctl logic for sliced VBI
+ *	capture
+ * @vidioc_try_fmt_sliced_vbi_out: pointer to the function that implements
+ *	:ref:`VIDIOC_TRY_FMT <vidioc_g_fmt>` ioctl logic for sliced VBI output
+ * @vidioc_try_fmt_vid_cap_mplane: pointer to the function that implements
+ *	:ref:`VIDIOC_TRY_FMT <vidioc_g_fmt>` ioctl logic for video capture
+ *	in multiple plane mode
+ * @vidioc_try_fmt_vid_out_mplane: pointer to the function that implements
+ *	:ref:`VIDIOC_TRY_FMT <vidioc_g_fmt>` ioctl logic for video out
+ *	in multiplane plane mode
+ * @vidioc_try_fmt_sdr_cap: pointer to the function that implements
+ *	:ref:`VIDIOC_TRY_FMT <vidioc_g_fmt>` ioctl logic for Software Defined
+ *	Radio capture
+ * @vidioc_try_fmt_sdr_out: pointer to the function that implements
+ *	:ref:`VIDIOC_TRY_FMT <vidioc_g_fmt>` ioctl logic for Software Defined
+ *	Radio output
+ * @vidioc_try_fmt_meta_cap: pointer to the function that implements
+ *	:ref:`VIDIOC_TRY_FMT <vidioc_g_fmt>` ioctl logic for metadata capture
+ * @vidioc_try_fmt_meta_out: pointer to the function that implements
+ *	:ref:`VIDIOC_TRY_FMT <vidioc_g_fmt>` ioctl logic for metadata output
+ * @vidioc_reqbufs: pointer to the function that implements
+ *	:ref:`VIDIOC_REQBUFS <vidioc_reqbufs>` ioctl
+ * @vidioc_querybuf: pointer to the function that implements
+ *	:ref:`VIDIOC_QUERYBUF <vidioc_querybuf>` ioctl
+ * @vidioc_qbuf: pointer to the function that implements
+ *	:ref:`VIDIOC_QBUF <vidioc_qbuf>` ioctl
+ * @vidioc_expbuf: pointer to the function that implements
+ *	:ref:`VIDIOC_EXPBUF <vidioc_expbuf>` ioctl
+ * @vidioc_dqbuf: pointer to the function that implements
+ *	:ref:`VIDIOC_DQBUF <vidioc_qbuf>` ioctl
+ * @vidioc_create_bufs: pointer to the function that implements
+ *	:ref:`VIDIOC_CREATE_BUFS <vidioc_create_bufs>` ioctl
+ * @vidioc_prepare_buf: pointer to the function that implements
+ *	:ref:`VIDIOC_PREPARE_BUF <vidioc_prepare_buf>` ioctl
+ * @vidioc_remove_bufs: pointer to the function that implements
+ *	:ref:`VIDIOC_REMOVE_BUFS <vidioc_remove_bufs>` ioctl
+ * @vidioc_overlay: pointer to the function that implements
+ *	:ref:`VIDIOC_OVERLAY <vidioc_overlay>` ioctl
+ * @vidioc_g_fbuf: pointer to the function that implements
+ *	:ref:`VIDIOC_G_FBUF <vidioc_g_fbuf>` ioctl
+ * @vidioc_s_fbuf: pointer to the function that implements
+ *	:ref:`VIDIOC_S_FBUF <vidioc_g_fbuf>` ioctl
+ * @vidioc_streamon: pointer to the function that implements
+ *	:ref:`VIDIOC_STREAMON <vidioc_streamon>` ioctl
+ * @vidioc_streamoff: pointer to the function that implements
+ *	:ref:`VIDIOC_STREAMOFF <vidioc_streamon>` ioctl
+ * @vidioc_g_std: pointer to the function that implements
+ *	:ref:`VIDIOC_G_STD <vidioc_g_std>` ioctl
+ * @vidioc_s_std: pointer to the function that implements
+ *	:ref:`VIDIOC_S_STD <vidioc_g_std>` ioctl
+ * @vidioc_querystd: pointer to the function that implements
+ *	:ref:`VIDIOC_QUERYSTD <vidioc_querystd>` ioctl
+ * @vidioc_enum_input: pointer to the function that implements
+ *	:ref:`VIDIOC_ENUM_INPUT <vidioc_g_input>` ioctl
+ * @vidioc_g_input: pointer to the function that implements
+ *	:ref:`VIDIOC_G_INPUT <vidioc_g_input>` ioctl
+ * @vidioc_s_input: pointer to the function that implements
+ *	:ref:`VIDIOC_S_INPUT <vidioc_g_input>` ioctl
+ * @vidioc_enum_output: pointer to the function that implements
+ *	:ref:`VIDIOC_ENUM_OUTPUT <vidioc_g_output>` ioctl
+ * @vidioc_g_output: pointer to the function that implements
+ *	:ref:`VIDIOC_G_OUTPUT <vidioc_g_output>` ioctl
+ * @vidioc_s_output: pointer to the function that implements
+ *	:ref:`VIDIOC_S_OUTPUT <vidioc_g_output>` ioctl
+ * @vidioc_query_ext_ctrl: pointer to the function that implements
+ *	:ref:`VIDIOC_QUERY_EXT_CTRL <vidioc_queryctrl>` ioctl
+ * @vidioc_g_ext_ctrls: pointer to the function that implements
+ *	:ref:`VIDIOC_G_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl
+ * @vidioc_s_ext_ctrls: pointer to the function that implements
+ *	:ref:`VIDIOC_S_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl
+ * @vidioc_try_ext_ctrls: pointer to the function that implements
+ *	:ref:`VIDIOC_TRY_EXT_CTRLS <vidioc_g_ext_ctrls>` ioctl
+ * @vidioc_querymenu: pointer to the function that implements
+ *	:ref:`VIDIOC_QUERYMENU <vidioc_queryctrl>` ioctl
+ * @vidioc_enumaudio: pointer to the function that implements
+ *	:ref:`VIDIOC_ENUMAUDIO <vidioc_enumaudio>` ioctl
+ * @vidioc_g_audio: pointer to the function that implements
+ *	:ref:`VIDIOC_G_AUDIO <vidioc_g_audio>` ioctl
+ * @vidioc_s_audio: pointer to the function that implements
+ *	:ref:`VIDIOC_S_AUDIO <vidioc_g_audio>` ioctl
+ * @vidioc_enumaudout: pointer to the function that implements
+ *	:ref:`VIDIOC_ENUMAUDOUT <vidioc_enumaudout>` ioctl
+ * @vidioc_g_audout: pointer to the function that implements
+ *	:ref:`VIDIOC_G_AUDOUT <vidioc_g_audout>` ioctl
+ * @vidioc_s_audout: pointer to the function that implements
+ *	:ref:`VIDIOC_S_AUDOUT <vidioc_g_audout>` ioctl
+ * @vidioc_g_modulator: pointer to the function that implements
+ *	:ref:`VIDIOC_G_MODULATOR <vidioc_g_modulator>` ioctl
+ * @vidioc_s_modulator: pointer to the function that implements
+ *	:ref:`VIDIOC_S_MODULATOR <vidioc_g_modulator>` ioctl
+ * @vidioc_g_pixelaspect: pointer to the function that implements
+ *	the pixelaspect part of the :ref:`VIDIOC_CROPCAP <vidioc_cropcap>` ioctl
+ * @vidioc_g_selection: pointer to the function that implements
+ *	:ref:`VIDIOC_G_SELECTION <vidioc_g_selection>` ioctl
+ * @vidioc_s_selection: pointer to the function that implements
+ *	:ref:`VIDIOC_S_SELECTION <vidioc_g_selection>` ioctl
+ * @vidioc_g_jpegcomp: pointer to the function that implements
+ *	:ref:`VIDIOC_G_JPEGCOMP <vidioc_g_jpegcomp>` ioctl
+ * @vidioc_s_jpegcomp: pointer to the function that implements
+ *	:ref:`VIDIOC_S_JPEGCOMP <vidioc_g_jpegcomp>` ioctl
+ * @vidioc_g_enc_index: pointer to the function that implements
+ *	:ref:`VIDIOC_G_ENC_INDEX <vidioc_g_enc_index>` ioctl
+ * @vidioc_encoder_cmd: pointer to the function that implements
+ *	:ref:`VIDIOC_ENCODER_CMD <vidioc_encoder_cmd>` ioctl
+ * @vidioc_try_encoder_cmd: pointer to the function that implements
+ *	:ref:`VIDIOC_TRY_ENCODER_CMD <vidioc_encoder_cmd>` ioctl
+ * @vidioc_decoder_cmd: pointer to the function that implements
+ *	:ref:`VIDIOC_DECODER_CMD <vidioc_decoder_cmd>` ioctl
+ * @vidioc_try_decoder_cmd: pointer to the function that implements
+ *	:ref:`VIDIOC_TRY_DECODER_CMD <vidioc_decoder_cmd>` ioctl
+ * @vidioc_g_parm: pointer to the function that implements
+ *	:ref:`VIDIOC_G_PARM <vidioc_g_parm>` ioctl
+ * @vidioc_s_parm: pointer to the function that implements
+ *	:ref:`VIDIOC_S_PARM <vidioc_g_parm>` ioctl
+ * @vidioc_g_tuner: pointer to the function that implements
+ *	:ref:`VIDIOC_G_TUNER <vidioc_g_tuner>` ioctl
+ * @vidioc_s_tuner: pointer to the function that implements
+ *	:ref:`VIDIOC_S_TUNER <vidioc_g_tuner>` ioctl
+ * @vidioc_g_frequency: pointer to the function that implements
+ *	:ref:`VIDIOC_G_FREQUENCY <vidioc_g_frequency>` ioctl
+ * @vidioc_s_frequency: pointer to the function that implements
+ *	:ref:`VIDIOC_S_FREQUENCY <vidioc_g_frequency>` ioctl
+ * @vidioc_enum_freq_bands: pointer to the function that implements
+ *	:ref:`VIDIOC_ENUM_FREQ_BANDS <vidioc_enum_freq_bands>` ioctl
+ * @vidioc_g_sliced_vbi_cap: pointer to the function that implements
+ *	:ref:`VIDIOC_G_SLICED_VBI_CAP <vidioc_g_sliced_vbi_cap>` ioctl
+ * @vidioc_log_status: pointer to the function that implements
+ *	:ref:`VIDIOC_LOG_STATUS <vidioc_log_status>` ioctl
+ * @vidioc_s_hw_freq_seek: pointer to the function that implements
+ *	:ref:`VIDIOC_S_HW_FREQ_SEEK <vidioc_s_hw_freq_seek>` ioctl
+ * @vidioc_g_register: pointer to the function that implements
+ *	:ref:`VIDIOC_DBG_G_REGISTER <vidioc_dbg_g_register>` ioctl
+ * @vidioc_s_register: pointer to the function that implements
+ *	:ref:`VIDIOC_DBG_S_REGISTER <vidioc_dbg_g_register>` ioctl
+ * @vidioc_g_chip_info: pointer to the function that implements
+ *	:ref:`VIDIOC_DBG_G_CHIP_INFO <vidioc_dbg_g_chip_info>` ioctl
+ * @vidioc_enum_framesizes: pointer to the function that implements
+ *	:ref:`VIDIOC_ENUM_FRAMESIZES <vidioc_enum_framesizes>` ioctl
+ * @vidioc_enum_frameintervals: pointer to the function that implements
+ *	:ref:`VIDIOC_ENUM_FRAMEINTERVALS <vidioc_enum_frameintervals>` ioctl
+ * @vidioc_s_dv_timings: pointer to the function that implements
+ *	:ref:`VIDIOC_S_DV_TIMINGS <vidioc_g_dv_timings>` ioctl
+ * @vidioc_g_dv_timings: pointer to the function that implements
+ *	:ref:`VIDIOC_G_DV_TIMINGS <vidioc_g_dv_timings>` ioctl
+ * @vidioc_query_dv_timings: pointer to the function that implements
+ *	:ref:`VIDIOC_QUERY_DV_TIMINGS <vidioc_query_dv_timings>` ioctl
+ * @vidioc_enum_dv_timings: pointer to the function that implements
+ *	:ref:`VIDIOC_ENUM_DV_TIMINGS <vidioc_enum_dv_timings>` ioctl
+ * @vidioc_dv_timings_cap: pointer to the function that implements
+ *	:ref:`VIDIOC_DV_TIMINGS_CAP <vidioc_dv_timings_cap>` ioctl
+ * @vidioc_g_edid: pointer to the function that implements
+ *	:ref:`VIDIOC_G_EDID <vidioc_g_edid>` ioctl
+ * @vidioc_s_edid: pointer to the function that implements
+ *	:ref:`VIDIOC_S_EDID <vidioc_g_edid>` ioctl
+ * @vidioc_subscribe_event: pointer to the function that implements
+ *	:ref:`VIDIOC_SUBSCRIBE_EVENT <vidioc_subscribe_event>` ioctl
+ * @vidioc_unsubscribe_event: pointer to the function that implements
+ *	:ref:`VIDIOC_UNSUBSCRIBE_EVENT <vidioc_unsubscribe_event>` ioctl
+ * @vidioc_default: pointed used to allow other ioctls
+ */
+struct v4l2_ioctl_ops {
+	/* ioctl callbacks */
+
+	/* VIDIOC_QUERYCAP handler */
+	int (*vidioc_querycap)(struct file *file, void *priv,
+			       struct v4l2_capability *cap);
+
+	/* VIDIOC_ENUM_FMT handlers */
+	int (*vidioc_enum_fmt_vid_cap)(struct file *file, void *priv,
+				       struct v4l2_fmtdesc *f);
+	int (*vidioc_enum_fmt_vid_overlay)(struct file *file, void *priv,
+					   struct v4l2_fmtdesc *f);
+	int (*vidioc_enum_fmt_vid_out)(struct file *file, void *priv,
+				       struct v4l2_fmtdesc *f);
+	int (*vidioc_enum_fmt_sdr_cap)(struct file *file, void *priv,
+				       struct v4l2_fmtdesc *f);
+	int (*vidioc_enum_fmt_sdr_out)(struct file *file, void *priv,
+				       struct v4l2_fmtdesc *f);
+	int (*vidioc_enum_fmt_meta_cap)(struct file *file, void *priv,
+					struct v4l2_fmtdesc *f);
+	int (*vidioc_enum_fmt_meta_out)(struct file *file, void *priv,
+					struct v4l2_fmtdesc *f);
+
+	/* VIDIOC_G_FMT handlers */
+	int (*vidioc_g_fmt_vid_cap)(struct file *file, void *priv,
+				    struct v4l2_format *f);
+	int (*vidioc_g_fmt_vid_overlay)(struct file *file, void *priv,
+					struct v4l2_format *f);
+	int (*vidioc_g_fmt_vid_out)(struct file *file, void *priv,
+				    struct v4l2_format *f);
+	int (*vidioc_g_fmt_vid_out_overlay)(struct file *file, void *priv,
+					    struct v4l2_format *f);
+	int (*vidioc_g_fmt_vbi_cap)(struct file *file, void *priv,
+				    struct v4l2_format *f);
+	int (*vidioc_g_fmt_vbi_out)(struct file *file, void *priv,
+				    struct v4l2_format *f);
+	int (*vidioc_g_fmt_sliced_vbi_cap)(struct file *file, void *priv,
+					   struct v4l2_format *f);
+	int (*vidioc_g_fmt_sliced_vbi_out)(struct file *file, void *priv,
+					   struct v4l2_format *f);
+	int (*vidioc_g_fmt_vid_cap_mplane)(struct file *file, void *priv,
+					   struct v4l2_format *f);
+	int (*vidioc_g_fmt_vid_out_mplane)(struct file *file, void *priv,
+					   struct v4l2_format *f);
+	int (*vidioc_g_fmt_sdr_cap)(struct file *file, void *priv,
+				    struct v4l2_format *f);
+	int (*vidioc_g_fmt_sdr_out)(struct file *file, void *priv,
+				    struct v4l2_format *f);
+	int (*vidioc_g_fmt_meta_cap)(struct file *file, void *priv,
+				     struct v4l2_format *f);
+	int (*vidioc_g_fmt_meta_out)(struct file *file, void *priv,
+				     struct v4l2_format *f);
+
+	/* VIDIOC_S_FMT handlers */
+	int (*vidioc_s_fmt_vid_cap)(struct file *file, void *priv,
+				    struct v4l2_format *f);
+	int (*vidioc_s_fmt_vid_overlay)(struct file *file, void *priv,
+					struct v4l2_format *f);
+	int (*vidioc_s_fmt_vid_out)(struct file *file, void *priv,
+				    struct v4l2_format *f);
+	int (*vidioc_s_fmt_vid_out_overlay)(struct file *file, void *priv,
+					    struct v4l2_format *f);
+	int (*vidioc_s_fmt_vbi_cap)(struct file *file, void *priv,
+				    struct v4l2_format *f);
+	int (*vidioc_s_fmt_vbi_out)(struct file *file, void *priv,
+				    struct v4l2_format *f);
+	int (*vidioc_s_fmt_sliced_vbi_cap)(struct file *file, void *priv,
+					   struct v4l2_format *f);
+	int (*vidioc_s_fmt_sliced_vbi_out)(struct file *file, void *priv,
+					   struct v4l2_format *f);
+	int (*vidioc_s_fmt_vid_cap_mplane)(struct file *file, void *priv,
+					   struct v4l2_format *f);
+	int (*vidioc_s_fmt_vid_out_mplane)(struct file *file, void *priv,
+					   struct v4l2_format *f);
+	int (*vidioc_s_fmt_sdr_cap)(struct file *file, void *priv,
+				    struct v4l2_format *f);
+	int (*vidioc_s_fmt_sdr_out)(struct file *file, void *priv,
+				    struct v4l2_format *f);
+	int (*vidioc_s_fmt_meta_cap)(struct file *file, void *priv,
+				     struct v4l2_format *f);
+	int (*vidioc_s_fmt_meta_out)(struct file *file, void *priv,
+				     struct v4l2_format *f);
+
+	/* VIDIOC_TRY_FMT handlers */
+	int (*vidioc_try_fmt_vid_cap)(struct file *file, void *priv,
+				      struct v4l2_format *f);
+	int (*vidioc_try_fmt_vid_overlay)(struct file *file, void *priv,
+					  struct v4l2_format *f);
+	int (*vidioc_try_fmt_vid_out)(struct file *file, void *priv,
+				      struct v4l2_format *f);
+	int (*vidioc_try_fmt_vid_out_overlay)(struct file *file, void *priv,
+					      struct v4l2_format *f);
+	int (*vidioc_try_fmt_vbi_cap)(struct file *file, void *priv,
+				      struct v4l2_format *f);
+	int (*vidioc_try_fmt_vbi_out)(struct file *file, void *priv,
+				      struct v4l2_format *f);
+	int (*vidioc_try_fmt_sliced_vbi_cap)(struct file *file, void *priv,
+					     struct v4l2_format *f);
+	int (*vidioc_try_fmt_sliced_vbi_out)(struct file *file, void *priv,
+					     struct v4l2_format *f);
+	int (*vidioc_try_fmt_vid_cap_mplane)(struct file *file, void *priv,
+					     struct v4l2_format *f);
+	int (*vidioc_try_fmt_vid_out_mplane)(struct file *file, void *priv,
+					     struct v4l2_format *f);
+	int (*vidioc_try_fmt_sdr_cap)(struct file *file, void *priv,
+				      struct v4l2_format *f);
+	int (*vidioc_try_fmt_sdr_out)(struct file *file, void *priv,
+				      struct v4l2_format *f);
+	int (*vidioc_try_fmt_meta_cap)(struct file *file, void *priv,
+				       struct v4l2_format *f);
+	int (*vidioc_try_fmt_meta_out)(struct file *file, void *priv,
+				       struct v4l2_format *f);
+
+	/* Buffer handlers */
+	int (*vidioc_reqbufs)(struct file *file, void *priv,
+			      struct v4l2_requestbuffers *b);
+	int (*vidioc_querybuf)(struct file *file, void *priv,
+			       struct v4l2_buffer *b);
+	int (*vidioc_qbuf)(struct file *file, void *priv,
+			   struct v4l2_buffer *b);
+	int (*vidioc_expbuf)(struct file *file, void *priv,
+			     struct v4l2_exportbuffer *e);
+	int (*vidioc_dqbuf)(struct file *file, void *priv,
+			    struct v4l2_buffer *b);
+
+	int (*vidioc_create_bufs)(struct file *file, void *priv,
+				  struct v4l2_create_buffers *b);
+	int (*vidioc_prepare_buf)(struct file *file, void *priv,
+				  struct v4l2_buffer *b);
+	int (*vidioc_remove_bufs)(struct file *file, void *priv,
+				  struct v4l2_remove_buffers *d);
+
+	int (*vidioc_overlay)(struct file *file, void *priv, unsigned int i);
+	int (*vidioc_g_fbuf)(struct file *file, void *priv,
+			     struct v4l2_framebuffer *a);
+	int (*vidioc_s_fbuf)(struct file *file, void *priv,
+			     const struct v4l2_framebuffer *a);
+
+		/* Stream on/off */
+	int (*vidioc_streamon)(struct file *file, void *priv,
+			       enum v4l2_buf_type i);
+	int (*vidioc_streamoff)(struct file *file, void *priv,
+				enum v4l2_buf_type i);
+
+		/*
+		 * Standard handling
+		 *
+		 * Note: ENUMSTD is handled by videodev.c
+		 */
+	int (*vidioc_g_std)(struct file *file, void *priv, v4l2_std_id *norm);
+	int (*vidioc_s_std)(struct file *file, void *priv, v4l2_std_id norm);
+	int (*vidioc_querystd)(struct file *file, void *priv, v4l2_std_id *a);
+
+		/* Input handling */
+	int (*vidioc_enum_input)(struct file *file, void *priv,
+				 struct v4l2_input *inp);
+	int (*vidioc_g_input)(struct file *file, void *priv, unsigned int *i);
+	int (*vidioc_s_input)(struct file *file, void *priv, unsigned int i);
+
+		/* Output handling */
+	int (*vidioc_enum_output)(struct file *file, void *priv,
+				  struct v4l2_output *a);
+	int (*vidioc_g_output)(struct file *file, void *priv, unsigned int *i);
+	int (*vidioc_s_output)(struct file *file, void *priv, unsigned int i);
+
+		/* Control handling */
+	int (*vidioc_query_ext_ctrl)(struct file *file, void *priv,
+				     struct v4l2_query_ext_ctrl *a);
+	int (*vidioc_g_ext_ctrls)(struct file *file, void *priv,
+				  struct v4l2_ext_controls *a);
+	int (*vidioc_s_ext_ctrls)(struct file *file, void *priv,
+				  struct v4l2_ext_controls *a);
+	int (*vidioc_try_ext_ctrls)(struct file *file, void *priv,
+				    struct v4l2_ext_controls *a);
+	int (*vidioc_querymenu)(struct file *file, void *priv,
+				struct v4l2_querymenu *a);
+
+	/* Audio ioctls */
+	int (*vidioc_enumaudio)(struct file *file, void *priv,
+				struct v4l2_audio *a);
+	int (*vidioc_g_audio)(struct file *file, void *priv,
+			      struct v4l2_audio *a);
+	int (*vidioc_s_audio)(struct file *file, void *priv,
+			      const struct v4l2_audio *a);
+
+	/* Audio out ioctls */
+	int (*vidioc_enumaudout)(struct file *file, void *priv,
+				 struct v4l2_audioout *a);
+	int (*vidioc_g_audout)(struct file *file, void *priv,
+			       struct v4l2_audioout *a);
+	int (*vidioc_s_audout)(struct file *file, void *priv,
+			       const struct v4l2_audioout *a);
+	int (*vidioc_g_modulator)(struct file *file, void *priv,
+				  struct v4l2_modulator *a);
+	int (*vidioc_s_modulator)(struct file *file, void *priv,
+				  const struct v4l2_modulator *a);
+	/* Crop ioctls */
+	int (*vidioc_g_pixelaspect)(struct file *file, void *priv,
+				    int buf_type, struct v4l2_fract *aspect);
+	int (*vidioc_g_selection)(struct file *file, void *priv,
+				  struct v4l2_selection *s);
+	int (*vidioc_s_selection)(struct file *file, void *priv,
+				  struct v4l2_selection *s);
+	/* Compression ioctls */
+	int (*vidioc_g_jpegcomp)(struct file *file, void *priv,
+				 struct v4l2_jpegcompression *a);
+	int (*vidioc_s_jpegcomp)(struct file *file, void *priv,
+				 const struct v4l2_jpegcompression *a);
+	int (*vidioc_g_enc_index)(struct file *file, void *priv,
+				  struct v4l2_enc_idx *a);
+	int (*vidioc_encoder_cmd)(struct file *file, void *priv,
+				  struct v4l2_encoder_cmd *a);
+	int (*vidioc_try_encoder_cmd)(struct file *file, void *priv,
+				      struct v4l2_encoder_cmd *a);
+	int (*vidioc_decoder_cmd)(struct file *file, void *priv,
+				  struct v4l2_decoder_cmd *a);
+	int (*vidioc_try_decoder_cmd)(struct file *file, void *priv,
+				      struct v4l2_decoder_cmd *a);
+
+	/* Stream type-dependent parameter ioctls */
+	int (*vidioc_g_parm)(struct file *file, void *priv,
+			     struct v4l2_streamparm *a);
+	int (*vidioc_s_parm)(struct file *file, void *priv,
+			     struct v4l2_streamparm *a);
+
+	/* Tuner ioctls */
+	int (*vidioc_g_tuner)(struct file *file, void *priv,
+			      struct v4l2_tuner *a);
+	int (*vidioc_s_tuner)(struct file *file, void *priv,
+			      const struct v4l2_tuner *a);
+	int (*vidioc_g_frequency)(struct file *file, void *priv,
+				  struct v4l2_frequency *a);
+	int (*vidioc_s_frequency)(struct file *file, void *priv,
+				  const struct v4l2_frequency *a);
+	int (*vidioc_enum_freq_bands)(struct file *file, void *priv,
+				      struct v4l2_frequency_band *band);
+
+	/* Sliced VBI cap */
+	int (*vidioc_g_sliced_vbi_cap)(struct file *file, void *priv,
+				       struct v4l2_sliced_vbi_cap *a);
+
+	/* Log status ioctl */
+	int (*vidioc_log_status)(struct file *file, void *priv);
+
+	int (*vidioc_s_hw_freq_seek)(struct file *file, void *priv,
+				     const struct v4l2_hw_freq_seek *a);
+
+	/* Debugging ioctls */
+#ifdef CONFIG_VIDEO_ADV_DEBUG
+	int (*vidioc_g_register)(struct file *file, void *priv,
+				 struct v4l2_dbg_register *reg);
+	int (*vidioc_s_register)(struct file *file, void *priv,
+				 const struct v4l2_dbg_register *reg);
+
+	int (*vidioc_g_chip_info)(struct file *file, void *priv,
+				  struct v4l2_dbg_chip_info *chip);
+#endif
+
+	int (*vidioc_enum_framesizes)(struct file *file, void *priv,
+				      struct v4l2_frmsizeenum *fsize);
+
+	int (*vidioc_enum_frameintervals)(struct file *file, void *priv,
+					  struct v4l2_frmivalenum *fival);
+
+	/* DV Timings IOCTLs */
+	int (*vidioc_s_dv_timings)(struct file *file, void *priv,
+				   struct v4l2_dv_timings *timings);
+	int (*vidioc_g_dv_timings)(struct file *file, void *priv,
+				   struct v4l2_dv_timings *timings);
+	int (*vidioc_query_dv_timings)(struct file *file, void *priv,
+				       struct v4l2_dv_timings *timings);
+	int (*vidioc_enum_dv_timings)(struct file *file, void *priv,
+				      struct v4l2_enum_dv_timings *timings);
+	int (*vidioc_dv_timings_cap)(struct file *file, void *priv,
+				     struct v4l2_dv_timings_cap *cap);
+	int (*vidioc_g_edid)(struct file *file, void *priv,
+			     struct v4l2_edid *edid);
+	int (*vidioc_s_edid)(struct file *file, void *priv,
+			     struct v4l2_edid *edid);
+
+	int (*vidioc_subscribe_event)(struct v4l2_fh *fh,
+				      const struct v4l2_event_subscription *sub);
+	int (*vidioc_unsubscribe_event)(struct v4l2_fh *fh,
+					const struct v4l2_event_subscription *sub);
+
+	/* For other private ioctls */
+	long (*vidioc_default)(struct file *file, void *priv,
+			       bool valid_prio, unsigned int cmd, void *arg);
+};
+
+
+/* v4l debugging and diagnostics */
+
+/* Device debug flags to be used with the video device debug attribute */
+
+/* Just log the ioctl name + error code */
+#define V4L2_DEV_DEBUG_IOCTL		0x01
+/* Log the ioctl name arguments + error code */
+#define V4L2_DEV_DEBUG_IOCTL_ARG	0x02
+/* Log the file operations open, release, mmap and get_unmapped_area */
+#define V4L2_DEV_DEBUG_FOP		0x04
+/* Log the read and write file operations and the VIDIOC_(D)QBUF ioctls */
+#define V4L2_DEV_DEBUG_STREAMING	0x08
+/* Log poll() */
+#define V4L2_DEV_DEBUG_POLL		0x10
+/* Log controls */
+#define V4L2_DEV_DEBUG_CTRL		0x20
+
+/*  Video standard functions  */
+
+/**
+ * v4l2_norm_to_name - Ancillary routine to analog TV standard name from its ID.
+ *
+ * @id:	analog TV standard ID.
+ *
+ * Return: returns a string with the name of the analog TV standard.
+ * If the standard is not found or if @id points to multiple standard,
+ * it returns "Unknown".
+ */
+const char *v4l2_norm_to_name(v4l2_std_id id);
+
+/**
+ * v4l2_video_std_frame_period - Ancillary routine that fills a
+ *	struct &v4l2_fract pointer with the default framerate fraction.
+ *
+ * @id: analog TV standard ID.
+ * @frameperiod: struct &v4l2_fract pointer to be filled
+ *
+ */
+void v4l2_video_std_frame_period(int id, struct v4l2_fract *frameperiod);
+
+/**
+ * v4l2_video_std_construct - Ancillary routine that fills in the fields of
+ *	a &v4l2_standard structure according to the @id parameter.
+ *
+ * @vs: struct &v4l2_standard pointer to be filled
+ * @id: analog TV standard ID.
+ * @name: name of the standard to be used
+ *
+ * .. note::
+ *
+ *    This ancillary routine is obsolete. Shouldn't be used on newer drivers.
+ */
+int v4l2_video_std_construct(struct v4l2_standard *vs,
+				    int id, const char *name);
+
+/**
+ * v4l_video_std_enumstd - Ancillary routine that fills in the fields of
+ *	a &v4l2_standard structure according to the @id and @vs->index
+ *	parameters.
+ *
+ * @vs: struct &v4l2_standard pointer to be filled.
+ * @id: analog TV standard ID.
+ *
+ */
+int v4l_video_std_enumstd(struct v4l2_standard *vs, v4l2_std_id id);
+
+/**
+ * v4l_printk_ioctl - Ancillary routine that prints the ioctl in a
+ *	human-readable format.
+ *
+ * @prefix: prefix to be added at the ioctl prints.
+ * @cmd: ioctl name
+ *
+ * .. note::
+ *
+ *    If prefix != %NULL, then it will issue a
+ *    ``printk(KERN_DEBUG "%s: ", prefix)`` first.
+ */
+void v4l_printk_ioctl(const char *prefix, unsigned int cmd);
+
+struct video_device;
+
+/* names for fancy debug output */
+
+/**
+ * var v4l2_field_names - Helper array mapping ``V4L2_FIELD_*`` to strings.
+ *
+ * Specially when printing debug messages, it is interesting to output
+ * the field order at the V4L2 buffers. This array associates all possible
+ * values of field pix format from V4L2 API into a string.
+ */
+extern const char *v4l2_field_names[];
+
+/**
+ * var v4l2_type_names - Helper array mapping ``V4L2_BUF_TYPE_*`` to strings.
+ *
+ * When printing debug messages, it is interesting to output the V4L2 buffer
+ * type number with a name that represents its content.
+ */
+extern const char *v4l2_type_names[];
+
+#ifdef CONFIG_COMPAT
+/**
+ * v4l2_compat_ioctl32 -32 Bits compatibility layer for 64 bits processors
+ *
+ * @file: Pointer to struct &file.
+ * @cmd: Ioctl name.
+ * @arg: Ioctl argument.
+ */
+long int v4l2_compat_ioctl32(struct file *file, unsigned int cmd,
+			     unsigned long arg);
+#endif
+
+unsigned int v4l2_compat_translate_cmd(unsigned int cmd);
+unsigned int v4l2_translate_cmd(unsigned int cmd);
+int v4l2_compat_get_user(void __user *arg, void *parg, unsigned int cmd);
+int v4l2_compat_put_user(void __user *arg, void *parg, unsigned int cmd);
+int v4l2_compat_get_array_args(struct file *file, void *mbuf,
+			       void __user *user_ptr, size_t array_size,
+			       unsigned int cmd, void *arg);
+int v4l2_compat_put_array_args(struct file *file, void __user *user_ptr,
+			       void *mbuf, size_t array_size,
+			       unsigned int cmd, void *arg);
+
+/**
+ * typedef v4l2_kioctl - Typedef used to pass an ioctl handler.
+ *
+ * @file: Pointer to struct &file.
+ * @cmd: Ioctl name.
+ * @arg: Ioctl argument.
+ */
+typedef long (*v4l2_kioctl)(struct file *file, unsigned int cmd, void *arg);
+
+/**
+ * video_usercopy - copies data from/to userspace memory when an ioctl is
+ *	issued.
+ *
+ * @file: Pointer to struct &file.
+ * @cmd: Ioctl name.
+ * @arg: Ioctl argument.
+ * @func: function that will handle the ioctl
+ *
+ * .. note::
+ *
+ *    This routine should be used only inside the V4L2 core.
+ */
+long int video_usercopy(struct file *file, unsigned int cmd,
+			unsigned long int arg, v4l2_kioctl func);
+
+/**
+ * video_ioctl2 - Handles a V4L2 ioctl.
+ *
+ * @file: Pointer to struct &file.
+ * @cmd: Ioctl name.
+ * @arg: Ioctl argument.
+ *
+ * Method used to hancle an ioctl. Should be used to fill the
+ * &v4l2_ioctl_ops.unlocked_ioctl on all V4L2 drivers.
+ */
+long int video_ioctl2(struct file *file,
+		      unsigned int cmd, unsigned long int arg);
+
+/*
+ * The user space interpretation of the 'v4l2_event' differs
+ * based on the 'time_t' definition on 32-bit architectures, so
+ * the kernel has to handle both.
+ * This is the old version for 32-bit architectures.
+ */
+struct v4l2_event_time32 {
+	__u32				type;
+	union {
+		struct v4l2_event_vsync		vsync;
+		struct v4l2_event_ctrl		ctrl;
+		struct v4l2_event_frame_sync	frame_sync;
+		struct v4l2_event_src_change	src_change;
+		struct v4l2_event_motion_det	motion_det;
+		__u8				data[64];
+	} u;
+	__u32				pending;
+	__u32				sequence;
+	struct old_timespec32		timestamp;
+	__u32				id;
+	__u32				reserved[8];
+};
+
+#define	VIDIOC_DQEVENT_TIME32	 _IOR('V', 89, struct v4l2_event_time32)
+
+struct v4l2_buffer_time32 {
+	__u32			index;
+	__u32			type;
+	__u32			bytesused;
+	__u32			flags;
+	__u32			field;
+	struct old_timeval32	timestamp;
+	struct v4l2_timecode	timecode;
+	__u32			sequence;
+
+	/* memory location */
+	__u32			memory;
+	union {
+		__u32           offset;
+		unsigned long   userptr;
+		struct v4l2_plane *planes;
+		__s32		fd;
+	} m;
+	__u32			length;
+	__u32			reserved2;
+	union {
+		__s32		request_fd;
+		__u32		reserved;
+	};
+};
+#define VIDIOC_QUERYBUF_TIME32	_IOWR('V',  9, struct v4l2_buffer_time32)
+#define VIDIOC_QBUF_TIME32	_IOWR('V', 15, struct v4l2_buffer_time32)
+#define VIDIOC_DQBUF_TIME32	_IOWR('V', 17, struct v4l2_buffer_time32)
+#define VIDIOC_PREPARE_BUF_TIME32 _IOWR('V', 93, struct v4l2_buffer_time32)
+
+#endif /* _V4L2_IOCTL_H */