Hi, On 09/01/2014 03:29 PM, Hans Verkuil wrote: > Hi Hans, > > At first glance this looks fine. But making changes in videobuf is always scary :-) > so I hope Marek can look at this as well. > > How well was this tested? I ran some tests on bttv which all ran well. Note that the code already allowed for going from say 4 buffers to 1, and the old code path for reqbufs was already calling __videobuf_free() before re-allocating the buffers again. So in essence this just changes things to allow the 4 buffers to 1 case to also be 4 buffers to 0. Regards, Hans > > I'll try do test this as well. > > Regards, > > Hans > > On 08/31/2014 12:19 PM, Hans de Goede wrote: >> All the infrastructure for this is already there, and despite our desires for >> the old videobuf code to go away, it is currently still in use in 18 drivers. >> >> Allowing reqbufs(0) makes these drivers behave consistent with modern drivers, >> making live easier for userspace, see e.g. : >> https://bugzilla.gnome.org/show_bug.cgi?id=735660 >> >> Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx> >> --- >> drivers/media/v4l2-core/videobuf-core.c | 11 ++++++----- >> 1 file changed, 6 insertions(+), 5 deletions(-) >> >> diff --git a/drivers/media/v4l2-core/videobuf-core.c b/drivers/media/v4l2-core/videobuf-core.c >> index fb5ee5d..b91a266 100644 >> --- a/drivers/media/v4l2-core/videobuf-core.c >> +++ b/drivers/media/v4l2-core/videobuf-core.c >> @@ -441,11 +441,6 @@ int videobuf_reqbufs(struct videobuf_queue *q, >> unsigned int size, count; >> int retval; >> >> - if (req->count < 1) { >> - dprintk(1, "reqbufs: count invalid (%d)\n", req->count); >> - return -EINVAL; >> - } >> - >> if (req->memory != V4L2_MEMORY_MMAP && >> req->memory != V4L2_MEMORY_USERPTR && >> req->memory != V4L2_MEMORY_OVERLAY) { >> @@ -471,6 +466,12 @@ int videobuf_reqbufs(struct videobuf_queue *q, >> goto done; >> } >> >> + if (req->count == 0) { >> + dprintk(1, "reqbufs: count invalid (%d)\n", req->count); >> + retval = __videobuf_free(q); >> + goto done; >> + } >> + >> count = req->count; >> if (count > VIDEO_MAX_FRAME) >> count = VIDEO_MAX_FRAME; >> > -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
