A simple comment in vhost_user_msg_handler() is not that robust.
Add a lock_all_qps property to message handlers so that their
implementation can add a build check and assert a vq is locked.
Signed-off-by: David Marchand <david.march...@redhat.com>
---
Changes since v2:
- dropped review tags,
- following use of static_assert() in RTE_BUILD_BUG_ON, reworked build
check by using enums (one enum is now defined per message type),
- as the added enums must be defined early, moved the definitions of
handlers at the top of the file,
Changes since v1:
- moved this patch as the last of the series,
---
lib/vhost/vhost_user.c | 128 +++++++++++++++++++++--------------------
1 file changed, 66 insertions(+), 62 deletions(-)
diff --git a/lib/vhost/vhost_user.c b/lib/vhost/vhost_user.c
index 3e8a87e517..84dae612c7 100644
--- a/lib/vhost/vhost_user.c
+++ b/lib/vhost/vhost_user.c
@@ -56,14 +56,72 @@
#define INFLIGHT_ALIGNMENT 64
#define INFLIGHT_VERSION 0x1
-typedef struct vhost_message_handler {
+typedef const struct vhost_message_handler {
const char *description;
int (*callback)(struct virtio_net **pdev, struct vhu_msg_context *ctx,
int main_fd);
bool accepts_fd;
+ bool lock_all_qps;
} vhost_message_handler_t;
static vhost_message_handler_t vhost_message_handlers[];
+#define VHOST_MESSAGE_HANDLERS \
+VHOST_MESSAGE_HANDLER(VHOST_USER_NONE, NULL, false, false) \
+VHOST_MESSAGE_HANDLER(VHOST_USER_GET_FEATURES, vhost_user_get_features, false,
false) \
+VHOST_MESSAGE_HANDLER(VHOST_USER_SET_FEATURES, vhost_user_set_features, false,
true) \
+VHOST_MESSAGE_HANDLER(VHOST_USER_SET_OWNER, vhost_user_set_owner, false, true)
\
+VHOST_MESSAGE_HANDLER(VHOST_USER_RESET_OWNER, vhost_user_reset_owner, false,
false) \
+VHOST_MESSAGE_HANDLER(VHOST_USER_SET_MEM_TABLE, vhost_user_set_mem_table,
true, true) \
+VHOST_MESSAGE_HANDLER(VHOST_USER_SET_LOG_BASE, vhost_user_set_log_base, true,
true) \
+VHOST_MESSAGE_HANDLER(VHOST_USER_SET_LOG_FD, vhost_user_set_log_fd, true,
true) \
+VHOST_MESSAGE_HANDLER(VHOST_USER_SET_VRING_NUM, vhost_user_set_vring_num,
false, true) \
+VHOST_MESSAGE_HANDLER(VHOST_USER_SET_VRING_ADDR, vhost_user_set_vring_addr,
false, true) \
+VHOST_MESSAGE_HANDLER(VHOST_USER_SET_VRING_BASE, vhost_user_set_vring_base,
false, true) \
+VHOST_MESSAGE_HANDLER(VHOST_USER_GET_VRING_BASE, vhost_user_get_vring_base,
false, false) \
+VHOST_MESSAGE_HANDLER(VHOST_USER_SET_VRING_KICK, vhost_user_set_vring_kick,
true, true) \
+VHOST_MESSAGE_HANDLER(VHOST_USER_SET_VRING_CALL, vhost_user_set_vring_call,
true, true) \
+VHOST_MESSAGE_HANDLER(VHOST_USER_SET_VRING_ERR, vhost_user_set_vring_err,
true, true) \
+VHOST_MESSAGE_HANDLER(VHOST_USER_GET_PROTOCOL_FEATURES,
vhost_user_get_protocol_features, \
+ false, false) \
+VHOST_MESSAGE_HANDLER(VHOST_USER_SET_PROTOCOL_FEATURES,
vhost_user_set_protocol_features, \
+ false, true) \
+VHOST_MESSAGE_HANDLER(VHOST_USER_GET_QUEUE_NUM, vhost_user_get_queue_num,
false, false) \
+VHOST_MESSAGE_HANDLER(VHOST_USER_SET_VRING_ENABLE,
vhost_user_set_vring_enable, false, true) \
+VHOST_MESSAGE_HANDLER(VHOST_USER_SEND_RARP, vhost_user_send_rarp, false, true)
\
+VHOST_MESSAGE_HANDLER(VHOST_USER_NET_SET_MTU, vhost_user_net_set_mtu, false,
true) \
+VHOST_MESSAGE_HANDLER(VHOST_USER_SET_BACKEND_REQ_FD, vhost_user_set_req_fd,
true, true) \
+VHOST_MESSAGE_HANDLER(VHOST_USER_IOTLB_MSG, vhost_user_iotlb_msg, false,
false) \
+VHOST_MESSAGE_HANDLER(VHOST_USER_GET_CONFIG, vhost_user_get_config, false,
false) \
+VHOST_MESSAGE_HANDLER(VHOST_USER_SET_CONFIG, vhost_user_set_config, false,
false) \
+VHOST_MESSAGE_HANDLER(VHOST_USER_POSTCOPY_ADVISE,
vhost_user_set_postcopy_advise, false, false) \
+VHOST_MESSAGE_HANDLER(VHOST_USER_POSTCOPY_LISTEN,
vhost_user_set_postcopy_listen, false, false) \
+VHOST_MESSAGE_HANDLER(VHOST_USER_POSTCOPY_END, vhost_user_postcopy_end, false,
false) \
+VHOST_MESSAGE_HANDLER(VHOST_USER_GET_INFLIGHT_FD, vhost_user_get_inflight_fd,
false, false) \
+VHOST_MESSAGE_HANDLER(VHOST_USER_SET_INFLIGHT_FD, vhost_user_set_inflight_fd,
true, false) \
+VHOST_MESSAGE_HANDLER(VHOST_USER_SET_STATUS, vhost_user_set_status, false,
false) \
+VHOST_MESSAGE_HANDLER(VHOST_USER_GET_STATUS, vhost_user_get_status, false,
false)
+
+#define VHOST_MESSAGE_HANDLER(id, handler, accepts_fd, lock_all_qps) \
+ id ## _LOCK_ALL_QPS = lock_all_qps,
+enum {
+ VHOST_MESSAGE_HANDLERS
+};
+#undef VHOST_MESSAGE_HANDLER
+
+/* vhost_user_msg_handler() locks all qps based on a handler's lock_all_qps.
+ * Later, a handler may need to ensure the vq has been locked (for example,
+ * when calling lock annotated helpers).
+ *
+ * Note: unfortunately, static_assert() does not see an array content as a
+ * constant expression. Because of this, we can't simply check for
+ * vhost_user_msg_handler[].lock_all_qps.
+ * Instead, define an enum for each handler.
+ */
+#define VHOST_USER_ASSERT_LOCK(dev, vq, id) do { \
+ RTE_BUILD_BUG_ON(id ## _LOCK_ALL_QPS == false); \
+ vq_assert_lock(dev, vq); \
+} while (0)
+
static int send_vhost_reply(struct virtio_net *dev, int sockfd, struct
vhu_msg_context *ctx);
static int read_vhost_message(struct virtio_net *dev, int sockfd, struct
vhu_msg_context *ctx);
@@ -400,7 +458,7 @@ vhost_user_set_features(struct virtio_net **pdev,
cleanup_vq(vq, 1);
cleanup_vq_inflight(dev, vq);
/* vhost_user_lock_all_queue_pairs locked all qps */
- vq_assert_lock(dev, vq);
+ VHOST_USER_ASSERT_LOCK(dev, vq,
VHOST_USER_SET_FEATURES);
rte_rwlock_write_unlock(&vq->access_lock);
free_vq(dev, vq);
}
@@ -927,7 +985,7 @@ vhost_user_set_vring_addr(struct virtio_net **pdev,
vq = dev->virtqueue[ctx->msg.payload.addr.index];
/* vhost_user_lock_all_queue_pairs locked all qps */
- vq_assert_lock(dev, vq);
+ VHOST_USER_ASSERT_LOCK(dev, vq, VHOST_USER_SET_VRING_ADDR);
access_ok = vq->access_ok;
@@ -1442,7 +1500,7 @@ vhost_user_set_mem_table(struct virtio_net **pdev,
if (vq->desc || vq->avail || vq->used) {
/* vhost_user_lock_all_queue_pairs locked all qps */
- vq_assert_lock(dev, vq);
+ VHOST_USER_ASSERT_LOCK(dev, vq,
VHOST_USER_SET_MEM_TABLE);
/*
* If the memory table got updated, the ring addresses
@@ -2234,7 +2292,7 @@ vhost_user_set_vring_enable(struct virtio_net **pdev,
vq = dev->virtqueue[index];
if (!(dev->flags & VIRTIO_DEV_VDPA_CONFIGURED)) {
/* vhost_user_lock_all_queue_pairs locked all qps */
- vq_assert_lock(dev, vq);
+ VHOST_USER_ASSERT_LOCK(dev, vq, VHOST_USER_SET_VRING_ENABLE);
if (enable && vq->async && vq->async->pkts_inflight_n) {
VHOST_CONFIG_LOG(dev->ifname, ERR,
"failed to enable vring. Inflight packets must
be completed first");
@@ -2838,42 +2896,8 @@ vhost_user_set_status(struct virtio_net **pdev,
return RTE_VHOST_MSG_RESULT_OK;
}
-#define VHOST_MESSAGE_HANDLERS \
-VHOST_MESSAGE_HANDLER(VHOST_USER_NONE, NULL, false) \
-VHOST_MESSAGE_HANDLER(VHOST_USER_GET_FEATURES, vhost_user_get_features, false)
\
-VHOST_MESSAGE_HANDLER(VHOST_USER_SET_FEATURES, vhost_user_set_features, false)
\
-VHOST_MESSAGE_HANDLER(VHOST_USER_SET_OWNER, vhost_user_set_owner, false) \
-VHOST_MESSAGE_HANDLER(VHOST_USER_RESET_OWNER, vhost_user_reset_owner, false) \
-VHOST_MESSAGE_HANDLER(VHOST_USER_SET_MEM_TABLE, vhost_user_set_mem_table,
true) \
-VHOST_MESSAGE_HANDLER(VHOST_USER_SET_LOG_BASE, vhost_user_set_log_base, true) \
-VHOST_MESSAGE_HANDLER(VHOST_USER_SET_LOG_FD, vhost_user_set_log_fd, true) \
-VHOST_MESSAGE_HANDLER(VHOST_USER_SET_VRING_NUM, vhost_user_set_vring_num,
false) \
-VHOST_MESSAGE_HANDLER(VHOST_USER_SET_VRING_ADDR, vhost_user_set_vring_addr,
false) \
-VHOST_MESSAGE_HANDLER(VHOST_USER_SET_VRING_BASE, vhost_user_set_vring_base,
false) \
-VHOST_MESSAGE_HANDLER(VHOST_USER_GET_VRING_BASE, vhost_user_get_vring_base,
false) \
-VHOST_MESSAGE_HANDLER(VHOST_USER_SET_VRING_KICK, vhost_user_set_vring_kick,
true) \
-VHOST_MESSAGE_HANDLER(VHOST_USER_SET_VRING_CALL, vhost_user_set_vring_call,
true) \
-VHOST_MESSAGE_HANDLER(VHOST_USER_SET_VRING_ERR, vhost_user_set_vring_err,
true) \
-VHOST_MESSAGE_HANDLER(VHOST_USER_GET_PROTOCOL_FEATURES,
vhost_user_get_protocol_features, false) \
-VHOST_MESSAGE_HANDLER(VHOST_USER_SET_PROTOCOL_FEATURES,
vhost_user_set_protocol_features, false) \
-VHOST_MESSAGE_HANDLER(VHOST_USER_GET_QUEUE_NUM, vhost_user_get_queue_num,
false) \
-VHOST_MESSAGE_HANDLER(VHOST_USER_SET_VRING_ENABLE,
vhost_user_set_vring_enable, false) \
-VHOST_MESSAGE_HANDLER(VHOST_USER_SEND_RARP, vhost_user_send_rarp, false) \
-VHOST_MESSAGE_HANDLER(VHOST_USER_NET_SET_MTU, vhost_user_net_set_mtu, false) \
-VHOST_MESSAGE_HANDLER(VHOST_USER_SET_BACKEND_REQ_FD, vhost_user_set_req_fd,
true) \
-VHOST_MESSAGE_HANDLER(VHOST_USER_IOTLB_MSG, vhost_user_iotlb_msg, false) \
-VHOST_MESSAGE_HANDLER(VHOST_USER_GET_CONFIG, vhost_user_get_config, false) \
-VHOST_MESSAGE_HANDLER(VHOST_USER_SET_CONFIG, vhost_user_set_config, false) \
-VHOST_MESSAGE_HANDLER(VHOST_USER_POSTCOPY_ADVISE,
vhost_user_set_postcopy_advise, false) \
-VHOST_MESSAGE_HANDLER(VHOST_USER_POSTCOPY_LISTEN,
vhost_user_set_postcopy_listen, false) \
-VHOST_MESSAGE_HANDLER(VHOST_USER_POSTCOPY_END, vhost_user_postcopy_end, false)
\
-VHOST_MESSAGE_HANDLER(VHOST_USER_GET_INFLIGHT_FD, vhost_user_get_inflight_fd,
false) \
-VHOST_MESSAGE_HANDLER(VHOST_USER_SET_INFLIGHT_FD, vhost_user_set_inflight_fd,
true) \
-VHOST_MESSAGE_HANDLER(VHOST_USER_SET_STATUS, vhost_user_set_status, false) \
-VHOST_MESSAGE_HANDLER(VHOST_USER_GET_STATUS, vhost_user_get_status, false)
-
-#define VHOST_MESSAGE_HANDLER(id, handler, accepts_fd) \
- [id] = { #id, handler, accepts_fd },
+#define VHOST_MESSAGE_HANDLER(id, handler, accepts_fd, lock_all_qps) \
+ [id] = { #id, handler, accepts_fd, id ## _LOCK_ALL_QPS },
static vhost_message_handler_t vhost_message_handlers[] = {
VHOST_MESSAGE_HANDLERS
};
@@ -3141,31 +3165,11 @@ vhost_user_msg_handler(int vid, int fd)
* inactive, so it is safe. Otherwise taking the access_lock
* would cause a dead lock.
*/
- switch (request) {
- case VHOST_USER_SET_FEATURES:
- case VHOST_USER_SET_PROTOCOL_FEATURES:
- case VHOST_USER_SET_OWNER:
- case VHOST_USER_SET_MEM_TABLE:
- case VHOST_USER_SET_LOG_BASE:
- case VHOST_USER_SET_LOG_FD:
- case VHOST_USER_SET_VRING_NUM:
- case VHOST_USER_SET_VRING_ADDR:
- case VHOST_USER_SET_VRING_BASE:
- case VHOST_USER_SET_VRING_KICK:
- case VHOST_USER_SET_VRING_CALL:
- case VHOST_USER_SET_VRING_ERR:
- case VHOST_USER_SET_VRING_ENABLE:
- case VHOST_USER_SEND_RARP:
- case VHOST_USER_NET_SET_MTU:
- case VHOST_USER_SET_BACKEND_REQ_FD:
+ if (msg_handler->lock_all_qps) {
if (!(dev->flags & VIRTIO_DEV_VDPA_CONFIGURED)) {
vhost_user_lock_all_queue_pairs(dev);
unlock_required = 1;
}
- break;
- default:
- break;
-
}
handled = false;
--
2.43.0
