media: v4l2-ctrls: alloc memory for p_req

To store request data the handler_new_ref() allocates memory
for it if needed.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
This commit is contained in:
Hans Verkuil 2018-05-21 04:54:38 -04:00 committed by Mauro Carvalho Chehab
parent 52beeddb68
commit 178543a3ba

View File

@ -2018,13 +2018,18 @@ EXPORT_SYMBOL(v4l2_ctrl_find);
/* Allocate a new v4l2_ctrl_ref and hook it into the handler. */
static int handler_new_ref(struct v4l2_ctrl_handler *hdl,
struct v4l2_ctrl *ctrl,
bool from_other_dev)
struct v4l2_ctrl_ref **ctrl_ref,
bool from_other_dev, bool allocate_req)
{
struct v4l2_ctrl_ref *ref;
struct v4l2_ctrl_ref *new_ref;
u32 id = ctrl->id;
u32 class_ctrl = V4L2_CTRL_ID2WHICH(id) | 1;
int bucket = id % hdl->nr_of_buckets; /* which bucket to use */
unsigned int size_extra_req = 0;
if (ctrl_ref)
*ctrl_ref = NULL;
/*
* Automatically add the control class if it is not yet present and
@ -2038,11 +2043,16 @@ static int handler_new_ref(struct v4l2_ctrl_handler *hdl,
if (hdl->error)
return hdl->error;
new_ref = kzalloc(sizeof(*new_ref), GFP_KERNEL);
if (allocate_req)
size_extra_req = ctrl->elems * ctrl->elem_size;
new_ref = kzalloc(sizeof(*new_ref) + size_extra_req, GFP_KERNEL);
if (!new_ref)
return handler_set_err(hdl, -ENOMEM);
new_ref->ctrl = ctrl;
new_ref->from_other_dev = from_other_dev;
if (size_extra_req)
new_ref->p_req.p = &new_ref[1];
if (ctrl->handler == hdl) {
/* By default each control starts in a cluster of its own.
new_ref->ctrl is basically a cluster array with one
@ -2082,6 +2092,8 @@ static int handler_new_ref(struct v4l2_ctrl_handler *hdl,
/* Insert the control node in the hash */
new_ref->next = hdl->buckets[bucket];
hdl->buckets[bucket] = new_ref;
if (ctrl_ref)
*ctrl_ref = new_ref;
unlock:
mutex_unlock(hdl->lock);
@ -2223,7 +2235,7 @@ static struct v4l2_ctrl *v4l2_ctrl_new(struct v4l2_ctrl_handler *hdl,
ctrl->type_ops->init(ctrl, idx, ctrl->p_new);
}
if (handler_new_ref(hdl, ctrl, false)) {
if (handler_new_ref(hdl, ctrl, NULL, false, false)) {
kvfree(ctrl);
return NULL;
}
@ -2416,7 +2428,7 @@ int v4l2_ctrl_add_handler(struct v4l2_ctrl_handler *hdl,
/* Filter any unwanted controls */
if (filter && !filter(ctrl))
continue;
ret = handler_new_ref(hdl, ctrl, from_other_dev);
ret = handler_new_ref(hdl, ctrl, NULL, from_other_dev, false);
if (ret)
break;
}