Re: [PATCH v6 01/17] media: v4l2-ioctl: check_ext_ctrls: Fix multiclass V4L2_CTRL_WHICH_DEF_VAL

[Ricardo Ribalda]

Hi Hans

On Thu, Mar 18, 2021 at 8:48 AM Hans Verkuil <hverkuil-cisco@xxxxxxxxx> wrote:
>
> On 18/03/2021 08:17, Ricardo Ribalda wrote:
> > Hi Hans
> >
> > Can I merge 1-3, but leave 4 as a separate one? It helps to tell a
> > story for 5 and  6.
>
> I really prefer it as a single patch. All four patches are basically a single big fix
> for v4l2-ioctl.c where the code for drivers that do not use the control framework had
> become very outdated. Fixing it in a single patch helps backporting to stable, and
> it is easier to review and see everything that had to be done to fix this.
>
> In this case I wondered when I was reviewing patch 1 why V4L2_CTRL_WHICH_DEF_VAL was
> just accepted without checking for S/TRY_EXT_CTRLS. Basically patch 1 is a broken fix
> w.r.t. DEF_VAL until patch 4, which really fixes it.
>
> Just do it all in a single patch, splitting it up doesn't work in this particular case.

Ok, thanks for the clarification :)
>
> Regards,
>
>         Hans
>
> >
> > Thanks
> >
> > On Thu, Mar 18, 2021 at 8:14 AM Hans Verkuil <hverkuil-cisco@xxxxxxxxx> wrote:
> >>
> >> Hi Ricardo,
> >>
> >> On 17/03/2021 17:44, Ricardo Ribalda wrote:
> >>> Drivers that do not use the ctrl-framework use this function instead.
> >>>
> >>> - Do not check for multiple classes when getting the DEF_VAL.
> >>>
> >>> Fixes v4l2-compliance:
> >>> Control ioctls (Input 0):
> >>>               fail: v4l2-test-controls.cpp(813): doioctl(node, VIDIOC_G_EXT_CTRLS, &ctrls)
> >>>       test VIDIOC_G/S/TRY_EXT_CTRLS: FAIL
> >>
> >> Can you merge patches 1-4 into a single patch? It's really one big fix since
> >> this code was never updated when new 'which' values were added. So keeping it
> >> together is, for once, actually preferred.
> >>
> >> You can add my:
> >>
> >> Reviewed-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
> >>
> >> after these 4 patches are merged. It looks much nicer now.
> >>
> >> Regards,
> >>
> >>         Hans
> >>
> >>>
> >>> Cc: stable@xxxxxxxxxxxxxxx
> >>> Fixes: 6fa6f831f095 ("media: v4l2-ctrls: add core request support")
> >>> Suggested-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
> >>> Signed-off-by: Ricardo Ribalda <ribalda@xxxxxxxxxxxx>
> >>> Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> >>> ---
> >>>  drivers/media/v4l2-core/v4l2-ioctl.c | 47 ++++++++++++++++------------
> >>>  1 file changed, 27 insertions(+), 20 deletions(-)
> >>>
> >>> diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
> >>> index 31d1342e61e8..403f957a1012 100644
> >>> --- a/drivers/media/v4l2-core/v4l2-ioctl.c
> >>> +++ b/drivers/media/v4l2-core/v4l2-ioctl.c
> >>> @@ -908,7 +908,7 @@ static void v4l_print_default(const void *arg, bool write_only)
> >>>       pr_cont("driver-specific ioctl\n");
> >>>  }
> >>>
> >>> -static int check_ext_ctrls(struct v4l2_ext_controls *c, int allow_priv)
> >>> +static bool check_ext_ctrls(struct v4l2_ext_controls *c, unsigned long ioctl)
> >>>  {
> >>>       __u32 i;
> >>>
> >>> @@ -917,23 +917,30 @@ static int check_ext_ctrls(struct v4l2_ext_controls *c, int allow_priv)
> >>>       for (i = 0; i < c->count; i++)
> >>>               c->controls[i].reserved2[0] = 0;
> >>>
> >>> -     /* V4L2_CID_PRIVATE_BASE cannot be used as control class
> >>> -        when using extended controls.
> >>> -        Only when passed in through VIDIOC_G_CTRL and VIDIOC_S_CTRL
> >>> -        is it allowed for backwards compatibility.
> >>> -      */
> >>> -     if (!allow_priv && c->which == V4L2_CID_PRIVATE_BASE)
> >>> -             return 0;
> >>> -     if (!c->which)
> >>> -             return 1;
> >>> +     switch (c->which) {
> >>> +     case V4L2_CID_PRIVATE_BASE:
> >>> +             /*
> >>> +              * V4L2_CID_PRIVATE_BASE cannot be used as control class
> >>> +              * when using extended controls.
> >>> +              * Only when passed in through VIDIOC_G_CTRL and VIDIOC_S_CTRL
> >>> +              * is it allowed for backwards compatibility.
> >>> +              */
> >>> +             if (ioctl == VIDIOC_G_CTRL || ioctl == VIDIOC_S_CROP)
> >>> +                     return false;
> >>> +             break;
> >>> +     case V4L2_CTRL_WHICH_DEF_VAL:
> >>> +     case V4L2_CTRL_WHICH_CUR_VAL:
> >>> +             return true;
> >>> +     }
> >>> +
> >>>       /* Check that all controls are from the same control class. */
> >>>       for (i = 0; i < c->count; i++) {
> >>>               if (V4L2_CTRL_ID2WHICH(c->controls[i].id) != c->which) {
> >>>                       c->error_idx = i;
> >>> -                     return 0;
> >>> +                     return false;
> >>>               }
> >>>       }
> >>> -     return 1;
> >>> +     return true;
> >>>  }
> >>>
> >>>  static int check_fmt(struct file *file, enum v4l2_buf_type type)
> >>> @@ -2229,7 +2236,7 @@ static int v4l_g_ctrl(const struct v4l2_ioctl_ops *ops,
> >>>       ctrls.controls = &ctrl;
> >>>       ctrl.id = p->id;
> >>>       ctrl.value = p->value;
> >>> -     if (check_ext_ctrls(&ctrls, 1)) {
> >>> +     if (check_ext_ctrls(&ctrls, VIDIOC_G_CTRL)) {
> >>>               int ret = ops->vidioc_g_ext_ctrls(file, fh, &ctrls);
> >>>
> >>>               if (ret == 0)
> >>> @@ -2263,7 +2270,7 @@ static int v4l_s_ctrl(const struct v4l2_ioctl_ops *ops,
> >>>       ctrls.controls = &ctrl;
> >>>       ctrl.id = p->id;
> >>>       ctrl.value = p->value;
> >>> -     if (check_ext_ctrls(&ctrls, 1))
> >>> +     if (check_ext_ctrls(&ctrls, VIDIOC_S_CTRL))
> >>>               return ops->vidioc_s_ext_ctrls(file, fh, &ctrls);
> >>>       return -EINVAL;
> >>>  }
> >>> @@ -2285,8 +2292,8 @@ static int v4l_g_ext_ctrls(const struct v4l2_ioctl_ops *ops,
> >>>                                       vfd, vfd->v4l2_dev->mdev, p);
> >>>       if (ops->vidioc_g_ext_ctrls == NULL)
> >>>               return -ENOTTY;
> >>> -     return check_ext_ctrls(p, 0) ? ops->vidioc_g_ext_ctrls(file, fh, p) :
> >>> -                                     -EINVAL;
> >>> +     return check_ext_ctrls(p, VIDIOC_G_EXT_CTRLS) ?
> >>> +                             ops->vidioc_g_ext_ctrls(file, fh, p) : -EINVAL;
> >>>  }
> >>>
> >>>  static int v4l_s_ext_ctrls(const struct v4l2_ioctl_ops *ops,
> >>> @@ -2306,8 +2313,8 @@ static int v4l_s_ext_ctrls(const struct v4l2_ioctl_ops *ops,
> >>>                                       vfd, vfd->v4l2_dev->mdev, p);
> >>>       if (ops->vidioc_s_ext_ctrls == NULL)
> >>>               return -ENOTTY;
> >>> -     return check_ext_ctrls(p, 0) ? ops->vidioc_s_ext_ctrls(file, fh, p) :
> >>> -                                     -EINVAL;
> >>> +     return check_ext_ctrls(p, VIDIOC_S_EXT_CTRLS) ?
> >>> +                             ops->vidioc_s_ext_ctrls(file, fh, p) : -EINVAL;
> >>>  }
> >>>
> >>>  static int v4l_try_ext_ctrls(const struct v4l2_ioctl_ops *ops,
> >>> @@ -2327,8 +2334,8 @@ static int v4l_try_ext_ctrls(const struct v4l2_ioctl_ops *ops,
> >>>                                         vfd, vfd->v4l2_dev->mdev, p);
> >>>       if (ops->vidioc_try_ext_ctrls == NULL)
> >>>               return -ENOTTY;
> >>> -     return check_ext_ctrls(p, 0) ? ops->vidioc_try_ext_ctrls(file, fh, p) :
> >>> -                                     -EINVAL;
> >>> +     return check_ext_ctrls(p, VIDIOC_TRY_EXT_CTRLS) ?
> >>> +                     ops->vidioc_try_ext_ctrls(file, fh, p) : -EINVAL;
> >>>  }
> >>>
> >>>  /*
> >>>
> >>
> >
> >
>


-- 
Ricardo Ribalda