diff options
| -rw-r--r-- | drivers/rpmsg/virtio_rpmsg_bus.c | 25 | ||||
| -rw-r--r-- | include/linux/rpmsg.h | 3 |
2 files changed, 22 insertions, 6 deletions
diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c index 9623327ba509..39d3aa41adda 100644 --- a/drivers/rpmsg/virtio_rpmsg_bus.c +++ b/drivers/rpmsg/virtio_rpmsg_bus.c @@ -227,6 +227,7 @@ static struct rpmsg_endpoint *__rpmsg_create_ept(struct virtproc_info *vrp, } kref_init(&ept->refcount); + mutex_init(&ept->cb_lock); ept->rpdev = rpdev; ept->cb = cb; @@ -324,10 +325,16 @@ EXPORT_SYMBOL(rpmsg_create_ept); static void __rpmsg_destroy_ept(struct virtproc_info *vrp, struct rpmsg_endpoint *ept) { + /* make sure new inbound messages can't find this ept anymore */ mutex_lock(&vrp->endpoints_lock); idr_remove(&vrp->endpoints, ept->addr); mutex_unlock(&vrp->endpoints_lock); + /* make sure in-flight inbound messages won't invoke cb anymore */ + mutex_lock(&ept->cb_lock); + ept->cb = NULL; + mutex_unlock(&ept->cb_lock); + kref_put(&ept->refcount, __ept_release); } @@ -821,14 +828,20 @@ static void rpmsg_recv_done(struct virtqueue *rvq) mutex_unlock(&vrp->endpoints_lock); - if (ept && ept->cb) - ept->cb(ept->rpdev, msg->data, msg->len, ept->priv, msg->src); - else - dev_warn(dev, "msg received with no recepient\n"); + if (ept) { + /* make sure ept->cb doesn't go away while we use it */ + mutex_lock(&ept->cb_lock); - /* farewell, ept, we don't need you anymore */ - if (ept) + if (ept->cb) + ept->cb(ept->rpdev, msg->data, msg->len, ept->priv, + msg->src); + + mutex_unlock(&ept->cb_lock); + + /* farewell, ept, we don't need you anymore */ kref_put(&ept->refcount, __ept_release); + } else + dev_warn(dev, "msg received with no recepient\n"); /* publish the real size of the buffer */ sg_init_one(&sg, msg, RPMSG_BUF_SIZE); diff --git a/include/linux/rpmsg.h b/include/linux/rpmsg.h index 195f373590b8..82a673905edb 100644 --- a/include/linux/rpmsg.h +++ b/include/linux/rpmsg.h @@ -39,6 +39,7 @@ #include <linux/device.h> #include <linux/mod_devicetable.h> #include <linux/kref.h> +#include <linux/mutex.h> /* The feature bitmap for virtio rpmsg */ #define VIRTIO_RPMSG_F_NS 0 /* RP supports name service notifications */ @@ -123,6 +124,7 @@ typedef void (*rpmsg_rx_cb_t)(struct rpmsg_channel *, void *, int, void *, u32); * @rpdev: rpmsg channel device * @refcount: when this drops to zero, the ept is deallocated * @cb: rx callback handler + * @cb_lock: must be taken before accessing/changing @cb * @addr: local rpmsg address * @priv: private data for the driver's use * @@ -144,6 +146,7 @@ struct rpmsg_endpoint { struct rpmsg_channel *rpdev; struct kref refcount; rpmsg_rx_cb_t cb; + struct mutex cb_lock; u32 addr; void *priv; }; |