Instead of checking the media request state is idle at one point, lock the
request for updating during the S_EXT_CTRLS call. As a by-product, finding
the request has been moved out of the v4l2_ctrls_find_req_obj() in order
to keep request object lookups to the minimum.
Signed-off-by: Sakari Ailus <sakari.ai...@linux.intel.com>
---
drivers/media/v4l2-core/v4l2-ctrls.c | 67 +++++++++++++++++++++---------------
1 file changed, 40 insertions(+), 27 deletions(-)
diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c
b/drivers/media/v4l2-core/v4l2-ctrls.c
index df58a23eb731a..1a99d6e238791 100644
--- a/drivers/media/v4l2-core/v4l2-ctrls.c
+++ b/drivers/media/v4l2-core/v4l2-ctrls.c
@@ -3208,9 +3208,8 @@ int __v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl,
static struct media_request_object *
v4l2_ctrls_find_req_obj(struct v4l2_ctrl_handler *hdl,
- struct media_device *mdev, s32 fd, bool set)
+ struct media_request *req, bool set)
{
- struct media_request *req = media_request_get_by_fd(mdev, fd);
struct media_request_object *obj;
struct v4l2_ctrl_handler *new_hdl;
int ret;
@@ -3218,36 +3217,29 @@ v4l2_ctrls_find_req_obj(struct v4l2_ctrl_handler *hdl,
if (IS_ERR(req))
return ERR_CAST(req);
- if (set && atomic_read(&req->state) != MEDIA_REQUEST_STATE_IDLE) {
- media_request_put(req);
+ if (set && WARN_ON(req->state != MEDIA_REQUEST_STATE_UPDATING))
return ERR_PTR(-EBUSY);
- }
obj = media_request_object_find(req, &req_ops, hdl);
- if (obj) {
- media_request_put(req);
+ if (obj)
return obj;
- }
new_hdl = kzalloc(sizeof(*new_hdl), GFP_KERNEL);
- if (!new_hdl) {
- ret = -ENOMEM;
- goto put;
- }
+ if (!new_hdl)
+ return ERR_PTR(-ENOMEM);
+
obj = &new_hdl->req_obj;
ret = v4l2_ctrl_handler_init(new_hdl, (hdl->nr_of_buckets - 1) * 8);
if (!ret)
ret = v4l2_ctrl_request_bind(req, new_hdl, hdl);
- if (!ret) {
- media_request_object_get(obj);
- media_request_put(req);
- return obj;
+ if (ret) {
+ kfree(new_hdl);
+
+ return ERR_PTR(ret);
}
- kfree(new_hdl);
-put:
- media_request_put(req);
- return ERR_PTR(ret);
+ media_request_object_get(obj);
+ return obj;
}
int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl, struct media_device *mdev,
@@ -3257,11 +3249,21 @@ int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl,
struct media_device *mdev,
int ret;
if (cs->which == V4L2_CTRL_WHICH_REQUEST_VAL) {
+ struct media_request *req;
+
if (!mdev || cs->request_fd < 0)
return -EINVAL;
- obj = v4l2_ctrls_find_req_obj(hdl, mdev, cs->request_fd, false);
+
+ req = media_request_get_by_fd(mdev, cs->request_fd);
+ if (!req)
+ return -ENOENT;
+
+ obj = v4l2_ctrls_find_req_obj(hdl, req, false);
+ /* Reference to the request held through obj */
+ media_request_put(req);
if (IS_ERR(obj))
return PTR_ERR(obj);
+
hdl = container_of(obj, struct v4l2_ctrl_handler,
req_obj);
}
@@ -3567,18 +3569,28 @@ static int try_set_ext_ctrls(struct v4l2_fh *fh,
struct v4l2_ext_controls *cs, bool set)
{
struct media_request_object *obj = NULL;
+ struct media_request *req = NULL;
int ret;
if (cs->which == V4L2_CTRL_WHICH_REQUEST_VAL) {
if (!mdev || cs->request_fd < 0)
return -EINVAL;
- obj = v4l2_ctrls_find_req_obj(hdl, mdev, cs->request_fd, true);
+
+ req = media_request_get_by_fd(mdev, cs->request_fd);
+ if (!req)
+ return -ENOENT;
+
+ ret = media_request_lock_for_update(req);
+ if (req) {
+ media_request_put(req);
+ return ret;
+ }
+
+ obj = v4l2_ctrls_find_req_obj(hdl, req, true);
+ /* Reference to the request held through obj */
+ media_request_object_put(obj);
if (IS_ERR(obj))
return PTR_ERR(obj);
- if (atomic_read(&obj->req->state) != MEDIA_REQUEST_STATE_IDLE) {
- media_request_object_put(obj);
- return -EBUSY;
- }
hdl = container_of(obj, struct v4l2_ctrl_handler,
req_obj);
}
@@ -3586,7 +3598,8 @@ static int try_set_ext_ctrls(struct v4l2_fh *fh,
ret = __try_set_ext_ctrls(fh, hdl, cs, set);
if (obj)
- media_request_object_put(obj);
+ media_request_unlock_for_update(obj->req);
+
return ret;
}
--
2.11.0
