diff --git a/tests/.gitignore b/tests/.gitignore
index 4faa3af..b90ea4b 100644
--- a/tests/.gitignore
+++ b/tests/.gitignore
@@ -87,6 +87,7 @@
 getxxid
 inet-cmsg
 ioctl
+ioctl_v4l2
 ioperm
 iopl
 ip_mreq
diff --git a/tests/Makefile.am b/tests/Makefile.am
index f13f897..48bf517 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -142,6 +142,7 @@
 	getxxid \
 	inet-cmsg \
 	ioctl \
+	ioctl_v4l2 \
 	ioperm \
 	iopl \
 	ip_mreq \
@@ -420,6 +421,7 @@
 	getxxid.test \
 	inet-cmsg.test \
 	ioctl.test \
+	ioctl_v4l2.test \
 	ioperm.test \
 	iopl.test \
 	ip_mreq.test \
diff --git a/tests/ioctl_v4l2.c b/tests/ioctl_v4l2.c
new file mode 100644
index 0000000..f64c784
--- /dev/null
+++ b/tests/ioctl_v4l2.c
@@ -0,0 +1,505 @@
+/*
+ * Copyright (c) 2015-2016 Dmitry V. Levin <ldv@altlinux.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "tests.h"
+#include <endian.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <linux/types.h>
+#include <linux/videodev2.h>
+
+static const unsigned int magic = 0xdeadbeef;
+
+static void
+init_magic(void *addr, const unsigned int size)
+{
+	unsigned int *p = addr;
+	const unsigned int *end = addr + size;
+
+	for (; p < end; ++p)
+		*(unsigned int *) p = magic;
+}
+
+int
+main(void )
+{
+	(void) tail_alloc(1);
+	const unsigned int size = get_page_size();
+	(void) tail_alloc(1);
+	void *const page = tail_alloc(size);
+	(void) tail_alloc(1);
+	init_magic(page, size);
+
+	const union u_pixel_format {
+		unsigned int pixelformat;
+		unsigned char cc[sizeof(int)];
+	} u = { .pixelformat = htole32(magic) };
+	unsigned int i;
+
+
+	/* VIDIOC_QUERYCAP */
+	ioctl(-1, VIDIOC_QUERYCAP, 0);
+	printf("ioctl(-1, VIDIOC_QUERYCAP, NULL) = -1 EBADF (%m)\n");
+
+	ioctl(-1, VIDIOC_QUERYCAP, page);
+	printf("ioctl(-1, VIDIOC_QUERYCAP, %p) = -1 EBADF (%m)\n", page);
+
+	/* VIDIOC_ENUM_FMT */
+	ioctl(-1, VIDIOC_ENUM_FMT, 0);
+	printf("ioctl(-1, VIDIOC_ENUM_FMT, NULL) = -1 EBADF (%m)\n");
+
+	struct v4l2_fmtdesc *const p_fmtdesc = tail_alloc(sizeof(*p_fmtdesc));
+	p_fmtdesc->index = magic;
+	p_fmtdesc->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+	ioctl(-1, VIDIOC_ENUM_FMT, p_fmtdesc);
+	printf("ioctl(-1, VIDIOC_ENUM_FMT, {index=%u"
+	       ", type=V4L2_BUF_TYPE_VIDEO_CAPTURE}) = -1 EBADF (%m)\n", magic);
+
+	/* VIDIOC_G_FMT */
+	ioctl(-1, VIDIOC_G_FMT, 0);
+	printf("ioctl(-1, VIDIOC_G_FMT, NULL) = -1 EBADF (%m)\n");
+
+	struct v4l2_format *const p_format =
+		tail_alloc(sizeof(*p_format));
+	p_format->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+
+	ioctl(-1, VIDIOC_G_FMT, p_format);
+	printf("ioctl(-1, VIDIOC_G_FMT"
+	       ", {type=V4L2_BUF_TYPE_VIDEO_CAPTURE}) = -1 EBADF (%m)\n");
+
+	/* VIDIOC_S_FMT */
+	ioctl(-1, VIDIOC_S_FMT, 0);
+	printf("ioctl(-1, VIDIOC_S_FMT, NULL) = -1 EBADF (%m)\n");
+
+	p_format->type = V4L2_BUF_TYPE_VIDEO_OUTPUT;
+	p_format->fmt.pix.width = 0xdad1beaf;
+	p_format->fmt.pix.height = 0xdad2beaf;
+	p_format->fmt.pix.pixelformat = 0xdeadbeef;
+	p_format->fmt.pix.field = V4L2_FIELD_NONE;
+	p_format->fmt.pix.bytesperline = 0xdad3beaf;
+	p_format->fmt.pix.sizeimage = 0xdad4beaf;
+	p_format->fmt.pix.colorspace = V4L2_COLORSPACE_JPEG;
+
+	ioctl(-1, VIDIOC_S_FMT, p_format);
+	printf("ioctl(-1, VIDIOC_S_FMT, {type=V4L2_BUF_TYPE_VIDEO_OUTPUT"
+	       ", fmt.pix={width=%u, height=%u, pixelformat="
+	       "v4l2_fourcc('\\x%x', '\\x%x', '\\x%x', '\\x%x')"
+	       ", field=V4L2_FIELD_NONE, bytesperline=%u, sizeimage=%u"
+	       ", colorspace=V4L2_COLORSPACE_JPEG}}) = -1 EBADF (%m)\n",
+	       p_format->fmt.pix.width, p_format->fmt.pix.height,
+	       u.cc[0], u.cc[1], u.cc[2], u.cc[3],
+	       p_format->fmt.pix.bytesperline, p_format->fmt.pix.sizeimage);
+
+	/* VIDIOC_TRY_FMT */
+	ioctl(-1, VIDIOC_TRY_FMT, 0);
+	printf("ioctl(-1, VIDIOC_TRY_FMT, NULL) = -1 EBADF (%m)\n");
+
+# if HAVE_DECL_V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE
+	memset(p_format, -1, sizeof(*p_format));
+	p_format->type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
+	p_format->fmt.pix_mp.width = 0xdad1beaf;
+	p_format->fmt.pix_mp.height = 0xdad2beaf;
+	p_format->fmt.pix_mp.pixelformat = 0xdeadbeef;
+	p_format->fmt.pix_mp.field = V4L2_FIELD_NONE;
+	p_format->fmt.pix_mp.colorspace = V4L2_COLORSPACE_JPEG;
+	for (i = 0; i < ARRAY_SIZE(p_format->fmt.pix_mp.plane_fmt); ++i) {
+		p_format->fmt.pix_mp.plane_fmt[i].sizeimage = 0xbadc0de0 | i;
+		p_format->fmt.pix_mp.plane_fmt[i].bytesperline = 0xdadbeaf0 | i;
+	}
+	ioctl(-1, VIDIOC_TRY_FMT, p_format);
+	printf("ioctl(-1, VIDIOC_TRY_FMT"
+	       ", {type=V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE"
+	       ", fmt.pix_mp={width=%u, height=%u, pixelformat="
+	       "v4l2_fourcc('\\x%x', '\\x%x', '\\x%x', '\\x%x')"
+	       ", field=V4L2_FIELD_NONE, colorspace=V4L2_COLORSPACE_JPEG"
+	       ", plane_fmt=[",
+	       p_format->fmt.pix_mp.width, p_format->fmt.pix_mp.height,
+	       u.cc[0], u.cc[1], u.cc[2], u.cc[3]);
+	for (i = 0; i < ARRAY_SIZE(p_format->fmt.pix_mp.plane_fmt); ++i) {
+		if (i)
+			printf(", ");
+		printf("{sizeimage=%u, bytesperline=%u}",
+		       p_format->fmt.pix_mp.plane_fmt[i].sizeimage,
+		       p_format->fmt.pix_mp.plane_fmt[i].bytesperline);
+	}
+	printf("], num_planes=%u}}) = -1 EBADF (%m)\n",
+	       p_format->fmt.pix_mp.num_planes);
+# else
+	ioctl(-1, VIDIOC_TRY_FMT, page);
+	printf("ioctl(-1, VIDIOC_TRY_FMT, {type=%#x /* V4L2_BUF_TYPE_??? */})"
+	       "= -1 EBADF (%m)\n", magic);
+# endif
+
+	/* VIDIOC_REQBUFS */
+	ioctl(-1, VIDIOC_REQBUFS, 0);
+	printf("ioctl(-1, VIDIOC_REQBUFS, NULL) = -1 EBADF (%m)\n");
+
+	ioctl(-1, VIDIOC_REQBUFS,
+	      page + size - sizeof(struct v4l2_requestbuffers));
+	printf("ioctl(-1, VIDIOC_REQBUFS, {count=%u, type=%#x"
+	       " /* V4L2_BUF_TYPE_??? */, memory=%#x /* V4L2_MEMORY_??? */})"
+	       " = -1 EBADF (%m)\n", magic, magic, magic);
+
+	/* VIDIOC_QUERYBUF */
+	ioctl(-1, VIDIOC_QUERYBUF, 0);
+	printf("ioctl(-1, VIDIOC_QUERYBUF, NULL) = -1 EBADF (%m)\n");
+
+	ioctl(-1, VIDIOC_QUERYBUF, page + size - sizeof(struct v4l2_buffer));
+	printf("ioctl(-1, VIDIOC_QUERYBUF, {type=%#x /* V4L2_BUF_TYPE_??? */"
+	       ", index=%u}) = -1 EBADF (%m)\n", magic, magic);
+
+	/* VIDIOC_QBUF */
+	ioctl(-1, VIDIOC_QBUF, 0);
+	printf("ioctl(-1, VIDIOC_QBUF, NULL) = -1 EBADF (%m)\n");
+
+	ioctl(-1, VIDIOC_QBUF, page + size - sizeof(struct v4l2_buffer));
+	printf("ioctl(-1, VIDIOC_QBUF, {type=%#x /* V4L2_BUF_TYPE_??? */"
+	       ", index=%u}) = -1 EBADF (%m)\n", magic, magic);
+
+	/* VIDIOC_DQBUF */
+	ioctl(-1, VIDIOC_DQBUF, 0);
+	printf("ioctl(-1, VIDIOC_DQBUF, NULL) = -1 EBADF (%m)\n");
+
+	ioctl(-1, VIDIOC_DQBUF, page + size - sizeof(struct v4l2_buffer));
+	printf("ioctl(-1, VIDIOC_DQBUF, {type=%#x"
+	       " /* V4L2_BUF_TYPE_??? */}) = -1 EBADF (%m)\n", magic);
+
+	/* VIDIOC_G_FBUF */
+	ioctl(-1, VIDIOC_G_FBUF, 0);
+	printf("ioctl(-1, VIDIOC_G_FBUF, NULL) = -1 EBADF (%m)\n");
+
+	ioctl(-1, VIDIOC_G_FBUF, page);
+	printf("ioctl(-1, VIDIOC_G_FBUF, %p) = -1 EBADF (%m)\n", page);
+
+	/* VIDIOC_S_FBUF */
+	ioctl(-1, VIDIOC_S_FBUF, 0);
+	printf("ioctl(-1, VIDIOC_S_FBUF, NULL) = -1 EBADF (%m)\n");
+
+	ioctl(-1, VIDIOC_S_FBUF, page + size - sizeof(struct v4l2_framebuffer));
+	printf("ioctl(-1, VIDIOC_S_FBUF, {capability=%#x"
+	       ", flags=%#x, base=%#lx}) = -1 EBADF (%m)\n",
+	       magic, magic, *(unsigned long *) page);
+
+	/* VIDIOC_STREAMON */
+	ioctl(-1, VIDIOC_STREAMON, 0);
+	printf("ioctl(-1, VIDIOC_STREAMON, NULL) = -1 EBADF (%m)\n");
+
+	ioctl(-1, VIDIOC_STREAMON, page + size - sizeof(int));
+	printf("ioctl(-1, VIDIOC_STREAMON, [%#x /* V4L2_BUF_TYPE_??? */])"
+	       " = -1 EBADF (%m)\n", magic);
+
+	/* VIDIOC_STREAMOFF */
+	ioctl(-1, VIDIOC_STREAMOFF, 0);
+	printf("ioctl(-1, VIDIOC_STREAMOFF, NULL) = -1 EBADF (%m)\n");
+
+	ioctl(-1, VIDIOC_STREAMOFF, page + size - sizeof(int));
+	printf("ioctl(-1, VIDIOC_STREAMOFF, [%#x /* V4L2_BUF_TYPE_??? */])"
+	       " = -1 EBADF (%m)\n", magic);
+
+	/* VIDIOC_G_PARM */
+	ioctl(-1, VIDIOC_G_PARM, 0);
+	printf("ioctl(-1, VIDIOC_G_PARM, NULL) = -1 EBADF (%m)\n");
+
+	ioctl(-1, VIDIOC_G_PARM, page + size - sizeof(struct v4l2_streamparm));
+	printf("ioctl(-1, VIDIOC_G_PARM, {type=%#x /* V4L2_BUF_TYPE_??? */})"
+	       " = -1 EBADF (%m)\n", magic);
+
+	/* VIDIOC_S_PARM */
+	ioctl(-1, VIDIOC_S_PARM, 0);
+	printf("ioctl(-1, VIDIOC_S_PARM, NULL) = -1 EBADF (%m)\n");
+
+	ioctl(-1, VIDIOC_S_PARM, page);
+	printf("ioctl(-1, VIDIOC_S_PARM, {type=%#x /* V4L2_BUF_TYPE_??? */})"
+	       " = -1 EBADF (%m)\n", magic);
+
+	struct v4l2_streamparm *const p_streamparm =
+		tail_alloc(sizeof(*p_streamparm));
+	p_streamparm->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+	p_streamparm->parm.capture.capability = V4L2_CAP_TIMEPERFRAME;
+	p_streamparm->parm.capture.capturemode = V4L2_MODE_HIGHQUALITY;
+	p_streamparm->parm.capture.timeperframe.numerator = 0xdeadbeef;
+	p_streamparm->parm.capture.timeperframe.denominator = 0xbadc0ded;
+	ioctl(-1, VIDIOC_S_PARM, p_streamparm);
+	printf("ioctl(-1, VIDIOC_S_PARM, {type=V4L2_BUF_TYPE_VIDEO_CAPTURE"
+	       ", parm.capture={capability=V4L2_CAP_TIMEPERFRAME"
+	       ", capturemode=V4L2_MODE_HIGHQUALITY, timeperframe=%u/%u"
+	       ", extendedmode=%u, readbuffers=%u}}) = -1 EBADF (%m)\n",
+	       p_streamparm->parm.capture.timeperframe.numerator,
+	       p_streamparm->parm.capture.timeperframe.denominator, -1U, -1U);
+
+	p_streamparm->type = V4L2_BUF_TYPE_VIDEO_OUTPUT;
+	p_streamparm->parm.output.outputmode = 0;
+	ioctl(-1, VIDIOC_S_PARM, p_streamparm);
+	printf("ioctl(-1, VIDIOC_S_PARM, {type=V4L2_BUF_TYPE_VIDEO_OUTPUT"
+	       ", parm.output={capability=V4L2_CAP_TIMEPERFRAME"
+	       ", outputmode=0, timeperframe=%u/%u"
+	       ", extendedmode=%u, writebuffers=%u}}) = -1 EBADF (%m)\n",
+	       p_streamparm->parm.output.timeperframe.numerator,
+	       p_streamparm->parm.output.timeperframe.denominator, -1U, -1U);
+
+	/* VIDIOC_G_STD */
+	ioctl(-1, VIDIOC_G_STD, 0);
+	printf("ioctl(-1, VIDIOC_G_STD, NULL) = -1 EBADF (%m)\n");
+
+	ioctl(-1, VIDIOC_G_STD, page);
+	printf("ioctl(-1, VIDIOC_G_STD, %p) = -1 EBADF (%m)\n", page);
+
+	/* VIDIOC_S_STD */
+	ioctl(-1, VIDIOC_S_STD, 0);
+	printf("ioctl(-1, VIDIOC_S_STD, NULL) = -1 EBADF (%m)\n");
+
+	ioctl(-1, VIDIOC_S_STD, page + size - sizeof(long long));
+	printf("ioctl(-1, VIDIOC_S_STD, [%#llx]) = -1 EBADF (%m)\n",
+	       *(unsigned long long *) page);
+
+	/* VIDIOC_ENUMSTD */
+	ioctl(-1, VIDIOC_ENUMSTD, 0);
+	printf("ioctl(-1, VIDIOC_ENUMSTD, NULL) = -1 EBADF (%m)\n");
+
+	struct v4l2_standard *const p_standard =
+		tail_alloc(sizeof(*p_standard));
+	p_standard->index = magic;
+	ioctl(-1, VIDIOC_ENUMSTD, p_standard);
+	printf("ioctl(-1, VIDIOC_ENUMSTD, {index=%u}) = -1 EBADF (%m)\n",
+	       magic);
+
+	/* VIDIOC_ENUMINPUT */
+	ioctl(-1, VIDIOC_ENUMINPUT, 0);
+	printf("ioctl(-1, VIDIOC_ENUMINPUT, NULL) = -1 EBADF (%m)\n");
+
+	ioctl(-1, VIDIOC_ENUMINPUT, page);
+	printf("ioctl(-1, VIDIOC_ENUMINPUT, {index=%u}) = -1 EBADF (%m)\n",
+	       magic);
+
+	/* VIDIOC_G_CTRL */
+	ioctl(-1, VIDIOC_G_CTRL, 0);
+	printf("ioctl(-1, VIDIOC_G_CTRL, NULL) = -1 EBADF (%m)\n");
+
+	ioctl(-1, VIDIOC_G_CTRL, page + size - sizeof(struct v4l2_control));
+	printf("ioctl(-1, VIDIOC_G_CTRL, {id=%#x /* V4L2_CID_??? */})"
+	       " = -1 EBADF (%m)\n", magic);
+
+	/* VIDIOC_S_CTRL */
+	ioctl(-1, VIDIOC_S_CTRL, 0);
+	printf("ioctl(-1, VIDIOC_S_CTRL, NULL) = -1 EBADF (%m)\n");
+
+	ioctl(-1, VIDIOC_S_CTRL, page + size - sizeof(struct v4l2_control));
+	printf("ioctl(-1, VIDIOC_S_CTRL, {id=%#x /* V4L2_CID_??? */"
+	       ", value=%d}) = -1 EBADF (%m)\n", magic, magic);
+
+	/* VIDIOC_QUERYCTRL */
+	ioctl(-1, VIDIOC_QUERYCTRL, 0);
+	printf("ioctl(-1, VIDIOC_QUERYCTRL, NULL) = -1 EBADF (%m)\n");
+
+	ioctl(-1, VIDIOC_QUERYCTRL,
+	      page + size - sizeof(struct v4l2_queryctrl));
+# ifdef V4L2_CTRL_FLAG_NEXT_CTRL
+	printf("ioctl(-1, VIDIOC_QUERYCTRL, {id=V4L2_CTRL_FLAG_NEXT_CTRL"
+	       "|%#x /* V4L2_CID_??? */}) = -1 EBADF (%m)\n",
+	       magic & ~V4L2_CTRL_FLAG_NEXT_CTRL);
+# else
+	printf("ioctl(-1, VIDIOC_QUERYCTRL, {id=%#x /* V4L2_CID_??? */})"
+	       " = -1 EBADF (%m)\n", magic);
+# endif
+
+	struct v4l2_queryctrl *const p_queryctrl =
+		tail_alloc(sizeof(*p_queryctrl));
+	p_queryctrl->id = V4L2_CID_SATURATION;
+	ioctl(-1, VIDIOC_QUERYCTRL, p_queryctrl);
+	printf("ioctl(-1, VIDIOC_QUERYCTRL, {id=V4L2_CID_SATURATION})"
+	       " = -1 EBADF (%m)\n");
+
+	/* VIDIOC_G_INPUT */
+	ioctl(-1, VIDIOC_G_INPUT, 0);
+	printf("ioctl(-1, VIDIOC_G_INPUT, NULL) = -1 EBADF (%m)\n");
+
+	ioctl(-1, VIDIOC_G_INPUT, page);
+	printf("ioctl(-1, VIDIOC_G_INPUT, %p) = -1 EBADF (%m)\n", page);
+
+	/* VIDIOC_S_INPUT */
+	ioctl(-1, VIDIOC_S_INPUT, 0);
+	printf("ioctl(-1, VIDIOC_S_INPUT, NULL) = -1 EBADF (%m)\n");
+
+	ioctl(-1, VIDIOC_S_INPUT, page + size - sizeof(int));
+	printf("ioctl(-1, VIDIOC_S_INPUT, [%u]) = -1 EBADF (%m)\n", magic);
+
+	/* VIDIOC_CROPCAP */
+	ioctl(-1, VIDIOC_CROPCAP, 0);
+	printf("ioctl(-1, VIDIOC_CROPCAP, NULL) = -1 EBADF (%m)\n");
+
+	ioctl(-1, VIDIOC_CROPCAP, page + size - sizeof(struct v4l2_cropcap));
+	printf("ioctl(-1, VIDIOC_CROPCAP, {type=%#x /* V4L2_BUF_TYPE_??? */})"
+	       " = -1 EBADF (%m)\n", magic);
+
+	/* VIDIOC_G_CROP */
+	ioctl(-1, VIDIOC_G_CROP, 0);
+	printf("ioctl(-1, VIDIOC_G_CROP, NULL) = -1 EBADF (%m)\n");
+
+	ioctl(-1, VIDIOC_G_CROP, page + size - sizeof(struct v4l2_crop));
+	printf("ioctl(-1, VIDIOC_G_CROP, {type=%#x /* V4L2_BUF_TYPE_??? */})"
+	       " = -1 EBADF (%m)\n", magic);
+
+	/* VIDIOC_S_CROP */
+	ioctl(-1, VIDIOC_S_CROP, 0);
+	printf("ioctl(-1, VIDIOC_S_CROP, NULL) = -1 EBADF (%m)\n");
+
+	ioctl(-1, VIDIOC_S_CROP, page + size - sizeof(struct v4l2_crop));
+	printf("ioctl(-1, VIDIOC_S_CROP, {type=%#x /* V4L2_BUF_TYPE_??? */"
+	       ", c={left=%d, top=%d, width=%u, height=%u}}) = -1 EBADF (%m)\n",
+	       magic, magic, magic, magic, magic);
+
+#ifdef VIDIOC_S_EXT_CTRLS
+	/* VIDIOC_S_EXT_CTRLS */
+	ioctl(-1, VIDIOC_S_EXT_CTRLS, 0);
+	printf("ioctl(-1, VIDIOC_S_EXT_CTRLS, NULL) = -1 EBADF (%m)\n");
+
+	struct v4l2_ext_controls *const p_ext_controls =
+		tail_alloc(sizeof(*p_ext_controls));
+	p_ext_controls->ctrl_class = V4L2_CTRL_CLASS_USER;
+	p_ext_controls->count = 0;
+	p_ext_controls->controls = (void *) -2UL;
+	ioctl(-1, VIDIOC_S_EXT_CTRLS, p_ext_controls);
+	printf("ioctl(-1, VIDIOC_S_EXT_CTRLS, {ctrl_class=V4L2_CTRL_CLASS_USER"
+	       ", count=%u}) = -1 EBADF (%m)\n", p_ext_controls->count);
+
+	p_ext_controls->ctrl_class = V4L2_CTRL_CLASS_MPEG;
+	p_ext_controls->count = magic;
+	ioctl(-1, VIDIOC_S_EXT_CTRLS, p_ext_controls);
+	printf("ioctl(-1, VIDIOC_S_EXT_CTRLS, {ctrl_class=V4L2_CTRL_CLASS_MPEG"
+	       ", count=%u, controls=%p}) = -1 EBADF (%m)\n",
+	       p_ext_controls->count, p_ext_controls->controls);
+
+	p_ext_controls->count = 2;
+	p_ext_controls->controls =
+		tail_alloc(sizeof(*p_ext_controls->controls) * p_ext_controls->count);
+	p_ext_controls->controls[0].id = V4L2_CID_BRIGHTNESS;
+	p_ext_controls->controls[0].size = 0;
+	p_ext_controls->controls[0].value64 = 0xfacefeeddeadbeef;
+	p_ext_controls->controls[1].id = V4L2_CID_CONTRAST;
+	p_ext_controls->controls[1].size = 2;
+	p_ext_controls->controls[1].string =
+		tail_alloc(p_ext_controls->controls[1].size);
+
+	ioctl(-1, VIDIOC_S_EXT_CTRLS, p_ext_controls);
+	printf("ioctl(-1, VIDIOC_S_EXT_CTRLS"
+	       ", {ctrl_class=V4L2_CTRL_CLASS_MPEG, count=%u, controls="
+	       "[{id=V4L2_CID_BRIGHTNESS, size=0, value=%d, value64=%lld}"
+	       ", {id=V4L2_CID_CONTRAST, size=2, string=\"\\377\\377\"}"
+	       "] => controls="
+	       "[{id=V4L2_CID_BRIGHTNESS, size=0, value=%d, value64=%lld}"
+	       ", {id=V4L2_CID_CONTRAST, size=2, string=\"\\377\\377\"}"
+	       "], error_idx=%u}) = -1 EBADF (%m)\n",
+	       p_ext_controls->count,
+	       p_ext_controls->controls[0].value,
+	       (long long) p_ext_controls->controls[0].value64,
+	       p_ext_controls->controls[0].value,
+	       (long long) p_ext_controls->controls[0].value64,
+	       p_ext_controls->error_idx);
+
+	++p_ext_controls->count;
+	ioctl(-1, VIDIOC_S_EXT_CTRLS, p_ext_controls);
+	printf("ioctl(-1, VIDIOC_S_EXT_CTRLS"
+	       ", {ctrl_class=V4L2_CTRL_CLASS_MPEG, count=%u, controls="
+	       "[{id=V4L2_CID_BRIGHTNESS, size=0, value=%d, value64=%lld}"
+	       ", {id=V4L2_CID_CONTRAST, size=2, string=\"\\377\\377\"}"
+	       ", %p]}) = -1 EBADF (%m)\n",
+	       p_ext_controls->count,
+	       p_ext_controls->controls[0].value,
+	       (long long) p_ext_controls->controls[0].value64,
+	       p_ext_controls->controls + 2);
+
+	/* VIDIOC_TRY_EXT_CTRLS */
+	ioctl(-1, VIDIOC_TRY_EXT_CTRLS, 0);
+	printf("ioctl(-1, VIDIOC_TRY_EXT_CTRLS, NULL) = -1 EBADF (%m)\n");
+
+	p_ext_controls->ctrl_class = V4L2_CTRL_CLASS_CAMERA;
+	p_ext_controls->count = magic;
+	p_ext_controls->controls = (void *) -2UL;
+	ioctl(-1, VIDIOC_TRY_EXT_CTRLS, p_ext_controls);
+	printf("ioctl(-1, VIDIOC_TRY_EXT_CTRLS"
+	       ", {ctrl_class=V4L2_CTRL_CLASS_CAMERA, count=%u, controls=%p})"
+	       " = -1 EBADF (%m)\n",
+	       p_ext_controls->count, p_ext_controls->controls);
+
+	/* VIDIOC_G_EXT_CTRLS */
+	ioctl(-1, VIDIOC_G_EXT_CTRLS, 0);
+	printf("ioctl(-1, VIDIOC_G_EXT_CTRLS, NULL) = -1 EBADF (%m)\n");
+
+	ioctl(-1, VIDIOC_G_EXT_CTRLS, p_ext_controls);
+	printf("ioctl(-1, VIDIOC_G_EXT_CTRLS"
+	       ", {ctrl_class=V4L2_CTRL_CLASS_CAMERA, count=%u, controls=%p"
+	       ", error_idx=%u}) = -1 EBADF (%m)\n",
+	       p_ext_controls->count, p_ext_controls->controls,
+	       p_ext_controls->error_idx);
+#endif /* VIDIOC_S_EXT_CTRLS */
+
+#ifdef VIDIOC_ENUM_FRAMESIZES
+	ioctl(-1, VIDIOC_ENUM_FRAMESIZES, 0);
+	printf("ioctl(-1, VIDIOC_ENUM_FRAMESIZES, NULL) = -1 EBADF (%m)\n");
+
+	struct v4l2_frmsizeenum *const p_frmsizeenum =
+		tail_alloc(sizeof(*p_frmsizeenum));
+	p_frmsizeenum->index = magic;
+	p_frmsizeenum->pixel_format = 0xfa5c2741;
+	const union u_pixel_format u_frmsizeenum = {
+		.pixelformat = htole32(p_frmsizeenum->pixel_format)
+	};
+	ioctl(-1, VIDIOC_ENUM_FRAMESIZES, p_frmsizeenum);
+	printf("ioctl(-1, VIDIOC_ENUM_FRAMESIZES, {index=%u"
+	       ", pixel_format=v4l2_fourcc('%c', '\\%c', '\\%c', '\\x%x')})"
+	       " = -1 EBADF (%m)\n", p_frmsizeenum->index,
+	       u_frmsizeenum.cc[0], u_frmsizeenum.cc[1],
+	       u_frmsizeenum.cc[2], u_frmsizeenum.cc[3]);
+#endif /* VIDIOC_ENUM_FRAMESIZES */
+
+#ifdef VIDIOC_ENUM_FRAMEINTERVALS
+	ioctl(-1, VIDIOC_ENUM_FRAMEINTERVALS, 0);
+	printf("ioctl(-1, VIDIOC_ENUM_FRAMEINTERVALS, NULL) = -1 EBADF (%m)\n");
+
+	ioctl(-1, VIDIOC_ENUM_FRAMEINTERVALS, page);
+	printf("ioctl(-1, VIDIOC_ENUM_FRAMEINTERVALS, {index=%u"
+	       ", pixel_format=v4l2_fourcc('\\x%x', '\\x%x', '\\x%x', '\\x%x')"
+	       ", width=%u, height=%u}) = -1 EBADF (%m)\n",
+	       magic, u.cc[0], u.cc[1], u.cc[2], u.cc[3], magic, magic);
+#endif /* VIDIOC_ENUM_FRAMEINTERVALS */
+
+#ifdef VIDIOC_CREATE_BUFS
+	ioctl(-1, VIDIOC_CREATE_BUFS, 0);
+	printf("ioctl(-1, VIDIOC_CREATE_BUFS, NULL) = -1 EBADF (%m)\n");
+
+	ioctl(-1, VIDIOC_CREATE_BUFS,
+	      page + size - sizeof(struct v4l2_create_buffers));
+	printf("ioctl(-1, VIDIOC_CREATE_BUFS, {count=%u, memory=%#x"
+	       " /* V4L2_MEMORY_??? */, format={type=%#x"
+	       " /* V4L2_BUF_TYPE_??? */}}) = -1 EBADF (%m)\n",
+	       magic, magic, magic);
+#endif /* VIDIOC_CREATE_BUFS */
+
+	puts("+++ exited with 0 +++");
+	return 0;
+}
diff --git a/tests/ioctl_v4l2.test b/tests/ioctl_v4l2.test
new file mode 100755
index 0000000..a092a3c
--- /dev/null
+++ b/tests/ioctl_v4l2.test
@@ -0,0 +1,5 @@
+#!/bin/sh
+
+# Check basic VIDIOC_* ioctl decoding.
+
+. "${srcdir=.}/ioctl.test"
diff --git a/v4l2.c b/v4l2.c
index bbf9436..7c4181a 100644
--- a/v4l2.c
+++ b/v4l2.c
@@ -29,11 +29,31 @@
 
 #include "defs.h"
 
+#include DEF_MPERS_TYPE(struct_v4l2_buffer)
+#include DEF_MPERS_TYPE(struct_v4l2_create_buffers)
+#include DEF_MPERS_TYPE(struct_v4l2_ext_control)
+#include DEF_MPERS_TYPE(struct_v4l2_ext_controls)
+#include DEF_MPERS_TYPE(struct_v4l2_format)
+#include DEF_MPERS_TYPE(struct_v4l2_framebuffer)
+#include DEF_MPERS_TYPE(struct_v4l2_input)
+#include DEF_MPERS_TYPE(struct_v4l2_standard)
+
 #include <stdint.h>
 #include <sys/ioctl.h>
 #include <linux/types.h>
 #include <linux/videodev2.h>
 
+typedef struct v4l2_buffer struct_v4l2_buffer;
+typedef struct v4l2_create_buffers struct_v4l2_create_buffers;
+typedef struct v4l2_ext_control struct_v4l2_ext_control;
+typedef struct v4l2_ext_controls struct_v4l2_ext_controls;
+typedef struct v4l2_format struct_v4l2_format;
+typedef struct v4l2_framebuffer struct_v4l2_framebuffer;
+typedef struct v4l2_input struct_v4l2_input;
+typedef struct v4l2_standard struct_v4l2_standard;
+
+#include MPERS_DEFS
+
 /* some historical constants */
 #ifndef V4L2_CID_HCENTER
 #define V4L2_CID_HCENTER (V4L2_CID_BASE+22)
@@ -171,7 +191,7 @@
 #include "xlat/v4l2_colorspaces.h"
 
 static void
-print_v4l2_format_fmt(const char *prefix, const struct v4l2_format *f)
+print_v4l2_format_fmt(const char *prefix, const struct_v4l2_format *f)
 {
 	switch (f->type) {
 	case V4L2_BUF_TYPE_VIDEO_CAPTURE:
@@ -254,7 +274,7 @@
 static int
 print_v4l2_format(struct tcb *tcp, const long arg, const bool is_get)
 {
-	struct v4l2_format f;
+	struct_v4l2_format f;
 
 	if (entering(tcp)) {
 		tprints(", ");
@@ -308,7 +328,7 @@
 static int
 print_v4l2_buffer(struct tcb *tcp, const unsigned int code, const long arg)
 {
-	struct v4l2_buffer b;
+	struct_v4l2_buffer b;
 
 	if (entering(tcp)) {
 		tprints(", ");
@@ -349,7 +369,7 @@
 static int
 print_v4l2_framebuffer(struct tcb *tcp, const long arg)
 {
-	struct v4l2_framebuffer b;
+	struct_v4l2_framebuffer b;
 
 	tprints(", ");
 	if (!umove_or_printaddr(tcp, arg, &b)) {
@@ -444,7 +464,7 @@
 static int
 print_v4l2_standard(struct tcb *tcp, const long arg)
 {
-	struct v4l2_standard s;
+	struct_v4l2_standard s;
 
 	if (entering(tcp)) {
 		tprints(", ");
@@ -471,7 +491,7 @@
 static int
 print_v4l2_input(struct tcb *tcp, const long arg)
 {
-	struct v4l2_input i;
+	struct_v4l2_input i;
 
 	if (entering(tcp)) {
 		tprints(", ");
@@ -622,7 +642,7 @@
 print_v4l2_ext_control_array(struct tcb *tcp, const unsigned long addr,
 			     const unsigned count)
 {
-	struct v4l2_ext_control ctrl;
+	struct_v4l2_ext_control ctrl;
 	const unsigned long size = count * sizeof(ctrl);
 	const unsigned long end = addr + size;
 	int rc = 0;
@@ -677,7 +697,7 @@
 static int
 print_v4l2_ext_controls(struct tcb *tcp, const long arg, const bool is_get)
 {
-	struct v4l2_ext_controls c;
+	struct_v4l2_ext_controls c;
 
 	if (entering(tcp)) {
 		tprints(", ");
@@ -803,7 +823,7 @@
 static int
 print_v4l2_create_buffers(struct tcb *tcp, const long arg)
 {
-	struct v4l2_create_buffers b;
+	struct_v4l2_create_buffers b;
 
 	if (entering(tcp)) {
 		tprints(", ");
@@ -815,7 +835,7 @@
 		printxval(v4l2_buf_types, b.format.type,
 			  "V4L2_BUF_TYPE_???");
 		print_v4l2_format_fmt(", ",
-				      (struct v4l2_format *) &b.format);
+				      (struct_v4l2_format *) &b.format);
 		tprints("}}");
 		return 0;
 	} else {
@@ -831,8 +851,7 @@
 }
 #endif /* VIDIOC_CREATE_BUFS */
 
-int
-v4l2_ioctl(struct tcb *tcp, const unsigned int code, const long arg)
+MPERS_PRINTER_DECL(int, v4l2_ioctl)(struct tcb *tcp, const unsigned int code, const long arg)
 {
 	if (!verbose(tcp))
 		return RVAL_DECODED;