struct list_head read_buffers;
wait_queue_head_t read_waitq;
+ struct kref kref;
};
/* Read out any raw xenbus messages queued up. */
mutex_unlock(&adap->dev_data->reply_mutex);
}
+static void xenbus_file_free(struct kref *kref)
+{
+ struct xenbus_file_priv *u;
+ struct xenbus_transaction_holder *trans, *tmp;
+ struct watch_adapter *watch, *tmp_watch;
+ struct read_buffer *rb, *tmp_rb;
+
+ u = container_of(kref, struct xenbus_file_priv, kref);
+
+ /*
+ * No need for locking here because there are no other users,
+ * by definition.
+ */
+
+ list_for_each_entry_safe(trans, tmp, &u->transactions, list) {
+ xenbus_transaction_end(trans->handle, 1);
+ list_del(&trans->list);
+ kfree(trans);
+ }
+
+ list_for_each_entry_safe(watch, tmp_watch, &u->watches, list) {
+ unregister_xenbus_watch(&watch->watch);
+ list_del(&watch->list);
+ free_watch_adapter(watch);
+ }
+
+ list_for_each_entry_safe(rb, tmp_rb, &u->read_buffers, list) {
+ list_del(&rb->list);
+ kfree(rb);
+ }
+ kfree(u);
+}
+
+static struct xenbus_transaction_holder *xenbus_get_transaction(
+ struct xenbus_file_priv *u, uint32_t tx_id)
+{
+ struct xenbus_transaction_holder *trans;
+
+ list_for_each_entry(trans, &u->transactions, list)
+ if (trans->handle.id == tx_id)
+ return trans;
+
+ return NULL;
+}
+
+void xenbus_dev_queue_reply(struct xb_req_data *req)
+{
+ struct xenbus_file_priv *u = req->par;
+ struct xenbus_transaction_holder *trans = NULL;
+ int rc;
+ LIST_HEAD(staging_q);
+
+ xs_request_exit(req);
+
+ mutex_lock(&u->msgbuffer_mutex);
+
+ if (req->type == XS_TRANSACTION_START) {
+ trans = xenbus_get_transaction(u, 0);
+ if (WARN_ON(!trans))
+ goto out;
+ if (req->msg.type == XS_ERROR) {
+ list_del(&trans->list);
+ kfree(trans);
+ } else {
+ rc = kstrtou32(req->body, 10, &trans->handle.id);
+ if (WARN_ON(rc))
+ goto out;
+ }
+ } else if (req->msg.type == XS_TRANSACTION_END) {
+ trans = xenbus_get_transaction(u, req->msg.tx_id);
+ if (WARN_ON(!trans))
+ goto out;
+ list_del(&trans->list);
+ kfree(trans);
+ }
+
+ mutex_unlock(&u->msgbuffer_mutex);
+
+ mutex_lock(&u->reply_mutex);
+ rc = queue_reply(&staging_q, &req->msg, sizeof(req->msg));
+ if (!rc)
+ rc = queue_reply(&staging_q, req->body, req->msg.len);
+ if (!rc) {
+ list_splice_tail(&staging_q, &u->read_buffers);
+ wake_up(&u->read_waitq);
+ } else {
+ queue_cleanup(&staging_q);
+ }
+ mutex_unlock(&u->reply_mutex);
+
+ kfree(req->body);
+ kfree(req);
+
+ kref_put(&u->kref, xenbus_file_free);
+
+ return;
+
+ out:
+ mutex_unlock(&u->msgbuffer_mutex);
+}
+
static int xenbus_command_reply(struct xenbus_file_priv *u,
unsigned int msg_type, const char *reply)
{
wake_up(&u->read_waitq);
mutex_unlock(&u->reply_mutex);
+ if (!rc)
+ kref_put(&u->kref, xenbus_file_free);
+
return rc;
}
struct xenbus_file_priv *u)
{
int rc;
- void *reply;
struct xenbus_transaction_holder *trans = NULL;
- LIST_HEAD(staging_q);
if (msg_type == XS_TRANSACTION_START) {
- trans = kmalloc(sizeof(*trans), GFP_KERNEL);
+ trans = kzalloc(sizeof(*trans), GFP_KERNEL);
if (!trans) {
rc = -ENOMEM;
goto out;
}
- } else if (u->u.msg.tx_id != 0) {
- list_for_each_entry(trans, &u->transactions, list)
- if (trans->handle.id == u->u.msg.tx_id)
- break;
- if (&trans->list == &u->transactions)
- return xenbus_command_reply(u, XS_ERROR, "ENOENT");
- }
-
- reply = xenbus_dev_request_and_reply(&u->u.msg);
- if (IS_ERR(reply)) {
- if (msg_type == XS_TRANSACTION_START)
- kfree(trans);
- rc = PTR_ERR(reply);
- goto out;
- }
+ list_add(&trans->list, &u->transactions);
+ } else if (u->u.msg.tx_id != 0 &&
+ !xenbus_get_transaction(u, u->u.msg.tx_id))
+ return xenbus_command_reply(u, XS_ERROR, "ENOENT");
- if (msg_type == XS_TRANSACTION_START) {
- if (u->u.msg.type == XS_ERROR)
- kfree(trans);
- else {
- trans->handle.id = simple_strtoul(reply, NULL, 0);
- list_add(&trans->list, &u->transactions);
- }
- } else if (u->u.msg.type == XS_TRANSACTION_END) {
- list_del(&trans->list);
+ rc = xenbus_dev_request_and_reply(&u->u.msg, u);
+ if (rc)
kfree(trans);
- }
-
- mutex_lock(&u->reply_mutex);
- rc = queue_reply(&staging_q, &u->u.msg, sizeof(u->u.msg));
- if (!rc)
- rc = queue_reply(&staging_q, reply, u->u.msg.len);
- if (!rc) {
- list_splice_tail(&staging_q, &u->read_buffers);
- wake_up(&u->read_waitq);
- } else {
- queue_cleanup(&staging_q);
- }
- mutex_unlock(&u->reply_mutex);
-
- kfree(reply);
out:
return rc;
* OK, now we have a complete message. Do something with it.
*/
+ kref_get(&u->kref);
+
msg_type = u->u.msg.type;
switch (msg_type) {
ret = xenbus_write_transaction(msg_type, u);
break;
}
- if (ret != 0)
+ if (ret != 0) {
rc = ret;
+ kref_put(&u->kref, xenbus_file_free);
+ }
/* Buffered message consumed */
u->len = 0;
if (u == NULL)
return -ENOMEM;
+ kref_init(&u->kref);
+
INIT_LIST_HEAD(&u->transactions);
INIT_LIST_HEAD(&u->watches);
INIT_LIST_HEAD(&u->read_buffers);
static int xenbus_file_release(struct inode *inode, struct file *filp)
{
struct xenbus_file_priv *u = filp->private_data;
- struct xenbus_transaction_holder *trans, *tmp;
- struct watch_adapter *watch, *tmp_watch;
- struct read_buffer *rb, *tmp_rb;
-
- /*
- * No need for locking here because there are no other users,
- * by definition.
- */
- list_for_each_entry_safe(trans, tmp, &u->transactions, list) {
- xenbus_transaction_end(trans->handle, 1);
- list_del(&trans->list);
- kfree(trans);
- }
-
- list_for_each_entry_safe(watch, tmp_watch, &u->watches, list) {
- unregister_xenbus_watch(&watch->watch);
- list_del(&watch->list);
- free_watch_adapter(watch);
- }
-
- list_for_each_entry_safe(rb, tmp_rb, &u->read_buffers, list) {
- list_del(&rb->list);
- kfree(rb);
- }
- kfree(u);
+ kref_put(&u->kref, xenbus_file_free);
return 0;
}
projects / karo-tx-linux.git / blobdiff