* concurrently, setting the counter to zero is enough for releasing
* this lock.
*/
- if (!exclusive)
+ switch (mode) {
+ case UVERBS_LOOKUP_READ:
- return __atomic_add_unless(&uobj->usecnt, 1, -1) == -1 ?
+ return atomic_fetch_add_unless(&uobj->usecnt, 1, -1) == -1 ?
-EBUSY : 0;
+ case UVERBS_LOOKUP_WRITE:
+ /* lock is exclusive */
+ return atomic_cmpxchg(&uobj->usecnt, 0, -1) == 0 ? 0 : -EBUSY;
+ case UVERBS_LOOKUP_DESTROY:
+ return 0;
+ }
+ return 0;
+}
+
+static void assert_uverbs_usecnt(struct ib_uobject *uobj,
+ enum rdma_lookup_mode mode)
+{
+#ifdef CONFIG_LOCKDEP
+ switch (mode) {
+ case UVERBS_LOOKUP_READ:
+ WARN_ON(atomic_read(&uobj->usecnt) <= 0);
+ break;
+ case UVERBS_LOOKUP_WRITE:
+ WARN_ON(atomic_read(&uobj->usecnt) != -1);
+ break;
+ case UVERBS_LOOKUP_DESTROY:
+ break;
+ }
+#endif
+}
+
+/*
+ * This must be called with the hw_destroy_rwsem locked for read or write,
+ * also the uobject itself must be locked for write.
+ *
+ * Upon return the HW object is guaranteed to be destroyed.
+ *
+ * For RDMA_REMOVE_ABORT, the hw_destroy_rwsem is not required to be held,
+ * however the type's allocat_commit function cannot have been called and the
+ * uobject cannot be on the uobjects_lists
+ *
+ * For RDMA_REMOVE_DESTROY the caller shold be holding a kref (eg via
+ * rdma_lookup_get_uobject) and the object is left in a state where the caller
+ * needs to call rdma_lookup_put_uobject.
+ *
+ * For all other destroy modes this function internally unlocks the uobject
+ * and consumes the kref on the uobj.
+ */
+static int uverbs_destroy_uobject(struct ib_uobject *uobj,
+ enum rdma_remove_reason reason)
+{
+ struct ib_uverbs_file *ufile = uobj->ufile;
+ unsigned long flags;
+ int ret;
+
+ lockdep_assert_held(&ufile->hw_destroy_rwsem);
+ assert_uverbs_usecnt(uobj, UVERBS_LOOKUP_WRITE);
+
+ if (uobj->object) {
+ ret = uobj->uapi_object->type_class->destroy_hw(uobj, reason);
+ if (ret) {
+ if (ib_is_destroy_retryable(ret, reason, uobj))
+ return ret;
+
+ /* Nothing to be done, dangle the memory and move on */
+ WARN(true,
+ "ib_uverbs: failed to remove uobject id %d, driver err=%d",
+ uobj->id, ret);
+ }
+
+ uobj->object = NULL;
+ }
- /* lock is either WRITE or DESTROY - should be exclusive */
- return atomic_cmpxchg(&uobj->usecnt, 0, -1) == 0 ? 0 : -EBUSY;
+ if (reason == RDMA_REMOVE_ABORT) {
+ WARN_ON(!list_empty(&uobj->list));
+ WARN_ON(!uobj->context);
+ uobj->uapi_object->type_class->alloc_abort(uobj);
+ }
+
+ uobj->context = NULL;
+
+ /*
+ * For DESTROY the usecnt is held write locked, the caller is expected
+ * to put it unlock and put the object when done with it. Only DESTROY
+ * can remove the IDR handle.
+ */
+ if (reason != RDMA_REMOVE_DESTROY)
+ atomic_set(&uobj->usecnt, 0);
+ else
+ uobj->uapi_object->type_class->remove_handle(uobj);
+
+ if (!list_empty(&uobj->list)) {
+ spin_lock_irqsave(&ufile->uobjects_lock, flags);
+ list_del_init(&uobj->list);
+ spin_unlock_irqrestore(&ufile->uobjects_lock, flags);
+
+ /*
+ * Pairs with the get in rdma_alloc_commit_uobject(), could
+ * destroy uobj.
+ */
+ uverbs_uobject_put(uobj);
+ }
+
+ /*
+ * When aborting the stack kref remains owned by the core code, and is
+ * not transferred into the type. Pairs with the get in alloc_uobj
+ */
+ if (reason == RDMA_REMOVE_ABORT)
+ uverbs_uobject_put(uobj);
+
+ return 0;
}
-static struct ib_uobject *alloc_uobj(struct ib_ucontext *context,
- const struct uverbs_obj_type *type)
+/*
+ * This calls uverbs_destroy_uobject() using the RDMA_REMOVE_DESTROY
+ * sequence. It should only be used from command callbacks. On success the
+ * caller must pair this with rdma_lookup_put_uobject(LOOKUP_WRITE). This
+ * version requires the caller to have already obtained an
+ * LOOKUP_DESTROY uobject kref.
+ */
+int uobj_destroy(struct ib_uobject *uobj)
{
- struct ib_uobject *uobj = kzalloc(type->obj_size, GFP_KERNEL);
+ struct ib_uverbs_file *ufile = uobj->ufile;
+ int ret;
+
+ down_read(&ufile->hw_destroy_rwsem);
+
+ ret = uverbs_try_lock_object(uobj, UVERBS_LOOKUP_WRITE);
+ if (ret)
+ goto out_unlock;
+
+ ret = uverbs_destroy_uobject(uobj, RDMA_REMOVE_DESTROY);
+ if (ret) {
+ atomic_set(&uobj->usecnt, 0);
+ goto out_unlock;
+ }
+out_unlock:
+ up_read(&ufile->hw_destroy_rwsem);
+ return ret;
+}
+
+/*
+ * uobj_get_destroy destroys the HW object and returns a handle to the uobj
+ * with a NULL object pointer. The caller must pair this with
+ * uverbs_put_destroy.
+ */
+struct ib_uobject *__uobj_get_destroy(const struct uverbs_api_object *obj,
+ u32 id, struct ib_uverbs_file *ufile)
+{
+ struct ib_uobject *uobj;
+ int ret;
+
+ uobj = rdma_lookup_get_uobject(obj, ufile, id, UVERBS_LOOKUP_DESTROY);
+ if (IS_ERR(uobj))
+ return uobj;
+
+ ret = uobj_destroy(uobj);
+ if (ret) {
+ rdma_lookup_put_uobject(uobj, UVERBS_LOOKUP_DESTROY);
+ return ERR_PTR(ret);
+ }
+
+ return uobj;
+}
+
+/*
+ * Does both uobj_get_destroy() and uobj_put_destroy(). Returns success_res
+ * on success (negative errno on failure). For use by callers that do not need
+ * the uobj.
+ */
+int __uobj_perform_destroy(const struct uverbs_api_object *obj, u32 id,
+ struct ib_uverbs_file *ufile, int success_res)
+{
+ struct ib_uobject *uobj;
+
+ uobj = __uobj_get_destroy(obj, id, ufile);
+ if (IS_ERR(uobj))
+ return PTR_ERR(uobj);
+
+ rdma_lookup_put_uobject(uobj, UVERBS_LOOKUP_WRITE);
+ return success_res;
+}
+
+/* alloc_uobj must be undone by uverbs_destroy_uobject() */
+static struct ib_uobject *alloc_uobj(struct ib_uverbs_file *ufile,
+ const struct uverbs_api_object *obj)
+{
+ struct ib_uobject *uobj;
+ struct ib_ucontext *ucontext;
+
+ ucontext = ib_uverbs_get_ucontext(ufile);
+ if (IS_ERR(ucontext))
+ return ERR_CAST(ucontext);
+
+ uobj = kzalloc(obj->type_attrs->obj_size, GFP_KERNEL);
if (!uobj)
return ERR_PTR(-ENOMEM);
/*
static int nvmet_rdma_post_recv(struct nvmet_rdma_device *ndev,
struct nvmet_rdma_cmd *cmd)
{
- struct ib_recv_wr *bad_wr;
+ int ret;
+
ib_dma_sync_single_for_device(ndev->device,
cmd->sge[0].addr, cmd->sge[0].length,
DMA_FROM_DEVICE);
if (ndev->srq)
- return ib_post_srq_recv(ndev->srq, &cmd->wr, NULL);
- return ib_post_recv(cmd->queue->cm_id->qp, &cmd->wr, NULL);
- ret = ib_post_srq_recv(ndev->srq, &cmd->wr, &bad_wr);
++ ret = ib_post_srq_recv(ndev->srq, &cmd->wr, NULL);
+ else
- ret = ib_post_recv(cmd->queue->cm_id->qp, &cmd->wr, &bad_wr);
++ ret = ib_post_recv(cmd->queue->cm_id->qp, &cmd->wr, NULL);
+
+ if (unlikely(ret))
+ pr_err("post_recv cmd failed\n");
+
+ return ret;
}
static void nvmet_rdma_process_wr_wait_list(struct nvmet_rdma_queue *queue)
rsp->send_sge.addr, rsp->send_sge.length,
DMA_TO_DEVICE);
- if (ib_post_send(cm_id->qp, first_wr, NULL)) {
- if (unlikely(ib_post_send(cm_id->qp, first_wr, &bad_wr))) {
++ if (unlikely(ib_post_send(cm_id->qp, first_wr, NULL))) {
pr_err("sending cmd response failed\n");
nvmet_rdma_release_rsp(rsp);
}
if (!ndev)
goto out_err;
- cm_id->device->attrs.max_sge) - 1;
+ inline_page_count = num_pages(port->inline_data_size);
+ inline_sge_count = max(cm_id->device->attrs.max_sge_rd,
++ cm_id->device->attrs.max_recv_sge) - 1;
+ if (inline_page_count > inline_sge_count) {
+ pr_warn("inline_data_size %d cannot be supported by device %s. Reducing to %lu.\n",
+ port->inline_data_size, cm_id->device->name,
+ inline_sge_count * PAGE_SIZE);
+ port->inline_data_size = inline_sge_count * PAGE_SIZE;
+ inline_page_count = inline_sge_count;
+ }
+ ndev->inline_data_size = port->inline_data_size;
+ ndev->inline_page_count = inline_page_count;
ndev->device = cm_id->device;
kref_init(&ndev->ref);
git.samba.org / sfrench / cifs-2.6.git / commitdiff