From 27cd2aba172dffb7819b9ca49a6a8acdbb8cf7e5 Mon Sep 17 00:00:00 2001 From: Hans Verkuil Date: Sat, 9 Jun 2012 08:55:31 -0300 Subject: [PATCH] [media] v4l2-ioctl.c: introduce INFO_FL_CLEAR to replace switch The switch statement that determines how much data should be copied from userspace is replaced by a table lookup. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- drivers/media/video/v4l2-ioctl.c | 103 ++++++++++++------------------- 1 file changed, 41 insertions(+), 62 deletions(-) diff --git a/drivers/media/video/v4l2-ioctl.c b/drivers/media/video/v4l2-ioctl.c index 46fd95327630..e2f77bc15954 100644 --- a/drivers/media/video/v4l2-ioctl.c +++ b/drivers/media/video/v4l2-ioctl.c @@ -394,7 +394,7 @@ static int check_fmt(const struct v4l2_ioctl_ops *ops, enum v4l2_buf_type type) struct v4l2_ioctl_info { unsigned int ioctl; - u16 flags; + u32 flags; const char * const name; }; @@ -402,6 +402,11 @@ struct v4l2_ioctl_info { #define INFO_FL_PRIO (1 << 0) /* This control can be valid if the filehandle passes a control handler. */ #define INFO_FL_CTRL (1 << 1) +/* Zero struct from after the field to the end */ +#define INFO_FL_CLEAR(v4l2_struct, field) \ + ((offsetof(struct v4l2_struct, field) + \ + sizeof(((struct v4l2_struct *)0)->field)) << 16) +#define INFO_FL_CLEAR_MASK (_IOC_SIZEMASK << 16) #define IOCTL_INFO(_ioctl, _flags) [_IOC_NR(_ioctl)] = { \ .ioctl = _ioctl, \ @@ -411,11 +416,11 @@ struct v4l2_ioctl_info { static struct v4l2_ioctl_info v4l2_ioctls[] = { IOCTL_INFO(VIDIOC_QUERYCAP, 0), - IOCTL_INFO(VIDIOC_ENUM_FMT, 0), - IOCTL_INFO(VIDIOC_G_FMT, 0), + IOCTL_INFO(VIDIOC_ENUM_FMT, INFO_FL_CLEAR(v4l2_fmtdesc, type)), + IOCTL_INFO(VIDIOC_G_FMT, INFO_FL_CLEAR(v4l2_format, type)), IOCTL_INFO(VIDIOC_S_FMT, INFO_FL_PRIO), IOCTL_INFO(VIDIOC_REQBUFS, INFO_FL_PRIO), - IOCTL_INFO(VIDIOC_QUERYBUF, 0), + IOCTL_INFO(VIDIOC_QUERYBUF, INFO_FL_CLEAR(v4l2_buffer, length)), IOCTL_INFO(VIDIOC_G_FBUF, 0), IOCTL_INFO(VIDIOC_S_FBUF, INFO_FL_PRIO), IOCTL_INFO(VIDIOC_OVERLAY, INFO_FL_PRIO), @@ -423,33 +428,33 @@ static struct v4l2_ioctl_info v4l2_ioctls[] = { IOCTL_INFO(VIDIOC_DQBUF, 0), IOCTL_INFO(VIDIOC_STREAMON, INFO_FL_PRIO), IOCTL_INFO(VIDIOC_STREAMOFF, INFO_FL_PRIO), - IOCTL_INFO(VIDIOC_G_PARM, 0), + IOCTL_INFO(VIDIOC_G_PARM, INFO_FL_CLEAR(v4l2_streamparm, type)), IOCTL_INFO(VIDIOC_S_PARM, INFO_FL_PRIO), IOCTL_INFO(VIDIOC_G_STD, 0), IOCTL_INFO(VIDIOC_S_STD, INFO_FL_PRIO), - IOCTL_INFO(VIDIOC_ENUMSTD, 0), - IOCTL_INFO(VIDIOC_ENUMINPUT, 0), + IOCTL_INFO(VIDIOC_ENUMSTD, INFO_FL_CLEAR(v4l2_standard, index)), + IOCTL_INFO(VIDIOC_ENUMINPUT, INFO_FL_CLEAR(v4l2_input, index)), IOCTL_INFO(VIDIOC_G_CTRL, INFO_FL_CTRL), IOCTL_INFO(VIDIOC_S_CTRL, INFO_FL_PRIO | INFO_FL_CTRL), - IOCTL_INFO(VIDIOC_G_TUNER, 0), + IOCTL_INFO(VIDIOC_G_TUNER, INFO_FL_CLEAR(v4l2_tuner, index)), IOCTL_INFO(VIDIOC_S_TUNER, INFO_FL_PRIO), IOCTL_INFO(VIDIOC_G_AUDIO, 0), IOCTL_INFO(VIDIOC_S_AUDIO, INFO_FL_PRIO), - IOCTL_INFO(VIDIOC_QUERYCTRL, INFO_FL_CTRL), - IOCTL_INFO(VIDIOC_QUERYMENU, INFO_FL_CTRL), + IOCTL_INFO(VIDIOC_QUERYCTRL, INFO_FL_CTRL | INFO_FL_CLEAR(v4l2_queryctrl, id)), + IOCTL_INFO(VIDIOC_QUERYMENU, INFO_FL_CTRL | INFO_FL_CLEAR(v4l2_querymenu, index)), IOCTL_INFO(VIDIOC_G_INPUT, 0), IOCTL_INFO(VIDIOC_S_INPUT, INFO_FL_PRIO), - IOCTL_INFO(VIDIOC_G_OUTPUT, 0), + IOCTL_INFO(VIDIOC_G_OUTPUT, INFO_FL_CLEAR(v4l2_output, index)), IOCTL_INFO(VIDIOC_S_OUTPUT, INFO_FL_PRIO), IOCTL_INFO(VIDIOC_ENUMOUTPUT, 0), IOCTL_INFO(VIDIOC_G_AUDOUT, 0), IOCTL_INFO(VIDIOC_S_AUDOUT, INFO_FL_PRIO), - IOCTL_INFO(VIDIOC_G_MODULATOR, 0), + IOCTL_INFO(VIDIOC_G_MODULATOR, INFO_FL_CLEAR(v4l2_modulator, index)), IOCTL_INFO(VIDIOC_S_MODULATOR, INFO_FL_PRIO), - IOCTL_INFO(VIDIOC_G_FREQUENCY, 0), + IOCTL_INFO(VIDIOC_G_FREQUENCY, INFO_FL_CLEAR(v4l2_frequency, tuner)), IOCTL_INFO(VIDIOC_S_FREQUENCY, INFO_FL_PRIO), - IOCTL_INFO(VIDIOC_CROPCAP, 0), - IOCTL_INFO(VIDIOC_G_CROP, 0), + IOCTL_INFO(VIDIOC_CROPCAP, INFO_FL_CLEAR(v4l2_cropcap, type)), + IOCTL_INFO(VIDIOC_G_CROP, INFO_FL_CLEAR(v4l2_crop, type)), IOCTL_INFO(VIDIOC_S_CROP, INFO_FL_PRIO), IOCTL_INFO(VIDIOC_G_SELECTION, 0), IOCTL_INFO(VIDIOC_S_SELECTION, INFO_FL_PRIO), @@ -457,20 +462,20 @@ static struct v4l2_ioctl_info v4l2_ioctls[] = { IOCTL_INFO(VIDIOC_S_JPEGCOMP, INFO_FL_PRIO), IOCTL_INFO(VIDIOC_QUERYSTD, 0), IOCTL_INFO(VIDIOC_TRY_FMT, 0), - IOCTL_INFO(VIDIOC_ENUMAUDIO, 0), - IOCTL_INFO(VIDIOC_ENUMAUDOUT, 0), + IOCTL_INFO(VIDIOC_ENUMAUDIO, INFO_FL_CLEAR(v4l2_audio, index)), + IOCTL_INFO(VIDIOC_ENUMAUDOUT, INFO_FL_CLEAR(v4l2_audioout, index)), IOCTL_INFO(VIDIOC_G_PRIORITY, 0), IOCTL_INFO(VIDIOC_S_PRIORITY, INFO_FL_PRIO), - IOCTL_INFO(VIDIOC_G_SLICED_VBI_CAP, 0), + IOCTL_INFO(VIDIOC_G_SLICED_VBI_CAP, INFO_FL_CLEAR(v4l2_sliced_vbi_cap, type)), IOCTL_INFO(VIDIOC_LOG_STATUS, 0), IOCTL_INFO(VIDIOC_G_EXT_CTRLS, INFO_FL_CTRL), IOCTL_INFO(VIDIOC_S_EXT_CTRLS, INFO_FL_PRIO | INFO_FL_CTRL), IOCTL_INFO(VIDIOC_TRY_EXT_CTRLS, 0), - IOCTL_INFO(VIDIOC_ENUM_FRAMESIZES, 0), - IOCTL_INFO(VIDIOC_ENUM_FRAMEINTERVALS, 0), + IOCTL_INFO(VIDIOC_ENUM_FRAMESIZES, INFO_FL_CLEAR(v4l2_frmsizeenum, pixel_format)), + IOCTL_INFO(VIDIOC_ENUM_FRAMEINTERVALS, INFO_FL_CLEAR(v4l2_frmivalenum, height)), IOCTL_INFO(VIDIOC_G_ENC_INDEX, 0), - IOCTL_INFO(VIDIOC_ENCODER_CMD, INFO_FL_PRIO), - IOCTL_INFO(VIDIOC_TRY_ENCODER_CMD, 0), + IOCTL_INFO(VIDIOC_ENCODER_CMD, INFO_FL_PRIO | INFO_FL_CLEAR(v4l2_encoder_cmd, flags)), + IOCTL_INFO(VIDIOC_TRY_ENCODER_CMD, INFO_FL_CLEAR(v4l2_encoder_cmd, flags)), IOCTL_INFO(VIDIOC_DECODER_CMD, INFO_FL_PRIO), IOCTL_INFO(VIDIOC_TRY_DECODER_CMD, 0), #ifdef CONFIG_VIDEO_ADV_DEBUG @@ -2106,45 +2111,6 @@ static long __video_do_ioctl(struct file *file, return ret; } -/* In some cases, only a few fields are used as input, i.e. when the app sets - * "index" and then the driver fills in the rest of the structure for the thing - * with that index. We only need to copy up the first non-input field. */ -static unsigned long cmd_input_size(unsigned int cmd) -{ - /* Size of structure up to and including 'field' */ -#define CMDINSIZE(cmd, type, field) \ - case VIDIOC_##cmd: \ - return offsetof(struct v4l2_##type, field) + \ - sizeof(((struct v4l2_##type *)0)->field); - - switch (cmd) { - CMDINSIZE(ENUM_FMT, fmtdesc, type); - CMDINSIZE(G_FMT, format, type); - CMDINSIZE(QUERYBUF, buffer, length); - CMDINSIZE(G_PARM, streamparm, type); - CMDINSIZE(ENUMSTD, standard, index); - CMDINSIZE(ENUMINPUT, input, index); - CMDINSIZE(G_CTRL, control, id); - CMDINSIZE(G_TUNER, tuner, index); - CMDINSIZE(QUERYCTRL, queryctrl, id); - CMDINSIZE(QUERYMENU, querymenu, index); - CMDINSIZE(ENUMOUTPUT, output, index); - CMDINSIZE(G_MODULATOR, modulator, index); - CMDINSIZE(G_FREQUENCY, frequency, tuner); - CMDINSIZE(CROPCAP, cropcap, type); - CMDINSIZE(G_CROP, crop, type); - CMDINSIZE(ENUMAUDIO, audio, index); - CMDINSIZE(ENUMAUDOUT, audioout, index); - CMDINSIZE(ENCODER_CMD, encoder_cmd, flags); - CMDINSIZE(TRY_ENCODER_CMD, encoder_cmd, flags); - CMDINSIZE(G_SLICED_VBI_CAP, sliced_vbi_cap, type); - CMDINSIZE(ENUM_FRAMESIZES, frmsizeenum, pixel_format); - CMDINSIZE(ENUM_FRAMEINTERVALS, frmivalenum, height); - default: - return _IOC_SIZE(cmd); - } -} - static int check_array_args(unsigned int cmd, void *parg, size_t *array_size, void * __user *user_ptr, void ***kernel_ptr) { @@ -2219,7 +2185,20 @@ video_usercopy(struct file *file, unsigned int cmd, unsigned long arg, err = -EFAULT; if (_IOC_DIR(cmd) & _IOC_WRITE) { - unsigned long n = cmd_input_size(cmd); + unsigned int n = _IOC_SIZE(cmd); + + /* + * In some cases, only a few fields are used as input, + * i.e. when the app sets "index" and then the driver + * fills in the rest of the structure for the thing + * with that index. We only need to copy up the first + * non-input field. + */ + if (v4l2_is_known_ioctl(cmd)) { + u32 flags = v4l2_ioctls[_IOC_NR(cmd)].flags; + if (flags & INFO_FL_CLEAR_MASK) + n = (flags & INFO_FL_CLEAR_MASK) >> 16; + } if (copy_from_user(parg, (void __user *)arg, n)) goto out; -- 2.30.2