DPDK: fix vRouter and Agent restart keeping the VM connectivity

vRouter restart: recover vring base after a crash from a shared memory.

Agent restart: close both the FD we listen and the FD we have accepted,
so QEMU detect the chardev disconnection, reconnects and replays all
the virtio messages.

Other minor changes (logs, typos, includes, renames, etc)

Change-Id: I4ebab47d40c162f3b31aa7c3782becece38bdae5
Closes-bug: #1537043

dpdk/vr_dpdk_netlink.c

@@ -98,6 +98,7 @@ dpdk_netlink_receive(void *usockp, char *nl_buf,
     int ret;
     struct vr_message request;
 
+    memset(&request, 0, sizeof(request));
     request.vr_message_buf = nl_buf + HDR_LEN;
     request.vr_message_len = nl_len - HDR_LEN;
 
@@ -159,6 +160,7 @@ vr_netlink_uvhost_vif_del(unsigned int vif_idx)
 {
     vrnu_msg_t msg;
 
+    memset(&msg, 0, sizeof(msg));
     msg.vrnum_type = VRNU_MSG_VIF_DEL;
     msg.vrnum_vif_del.vrnu_vif_idx = vif_idx;
 
@@ -188,6 +190,7 @@ vr_netlink_uvhost_vif_add(char *vif_name, unsigned int vif_idx,
 {
     vrnu_msg_t msg;
 
+    memset(&msg, 0, sizeof(msg));
     msg.vrnum_type = VRNU_MSG_VIF_ADD;
     strncpy(msg.vrnum_vif_add.vrnu_vif_name, vif_name,
             sizeof(msg.vrnum_vif_add.vrnu_vif_name) - 1);

dpdk/vr_dpdk_virtio.c

@@ -217,8 +217,8 @@ vr_dpdk_virtio_uvh_get_blk_size(int fd, uint64_t *const blksize)
     if (!ret){
         *blksize = (uint64_t)fd_stat.st_blksize;
     } else {
-      RTE_LOG(DEBUG, UVHOST, "Function fstat() failed: %s  %s \n",
-              __func__, strerror(errno));
+        RTE_LOG(DEBUG, UVHOST, "Error getting file status for FD %d: %s (%d)\n",
+                fd, strerror(errno), errno);
     }
 
     return ret;
@@ -242,8 +242,8 @@ vr_dpdk_virtio_uvh_vif_munmap(vr_dpdk_uvh_vif_mmap_addr_t *const vif_mmap_addrs)
             ret = vr_dpdk_virtio_uvh_vif_region_munmap(vif_data_mmap);
             if (ret) {
                 RTE_LOG(INFO, UVHOST,
-                        "munmap() failed: %s , memleak: vif_idx_region %d %s\n",
-                        strerror(errno), i, __func__);
+                        "Error unmapping memory region %d: %s (%d)\n",
+                        i, strerror(errno), errno);
             }
             memset(vif_data_mmap, 0, sizeof(vr_dpdk_uvh_mmap_addr_t));
         }
@@ -619,6 +619,8 @@ dpdk_virtio_from_vm_rx(void *port, struct rte_mbuf **pkts, uint32_t max_pkts)
     vq->vdv_last_used_idx += pkts_sent;
     rte_wmb();
     vq->vdv_used->idx += pkts_sent;
+    RTE_LOG(DEBUG, VROUTER, "%s: vif %d vq %p last_used_idx %d used->idx %d\n",
+            __func__, vq->vdv_vif_idx, vq, vq->vdv_last_used_idx, vq->vdv_used->idx);
     /* call guest if required (fixes iperf issue) */
     if (unlikely(!(vq->vdv_avail->flags & VRING_AVAIL_F_NO_INTERRUPT))) {
         p->nb_syscalls++;
@@ -829,6 +831,8 @@ dpdk_virtio_dev_to_vm_tx_burst(struct dpdk_virtio_writer *p,
 
     *(volatile uint16_t *)&vq->vdv_used->idx += count;
     vq->vdv_last_used_idx = res_end_idx;
+    RTE_LOG(DEBUG, VROUTER, "%s: vif %d vq %p last_used_idx %d used->idx %d\n",
+            __func__, vq->vdv_vif_idx, vq, vq->vdv_last_used_idx, vq->vdv_used->idx);
 
     /* flush used->idx update before we read avail->flags. */
     rte_mb();
@@ -969,10 +973,44 @@ vr_dpdk_virtio_get_vring_base(unsigned int vif_idx, unsigned int vring_idx,
 }
 
 /*
- * vr_dpdk_set_vring_addr - Sets the address of the virtio descruptor and
+ * vr_dpdk_virtio_recover_vring_base - recovers the vring base from the shared
+ * memory after vRouter crash.
+ *
+ * Returns 0 on success, -1 otherwise.
+ */
+int
+vr_dpdk_virtio_recover_vring_base(unsigned int vif_idx, unsigned int vring_idx)
+{
+    vr_dpdk_virtioq_t *vq;
+
+    if ((vif_idx >= VR_MAX_INTERFACES)
+        || (vring_idx >= (2 * VR_DPDK_VIRTIO_MAX_QUEUES))) {
+        return -1;
+    }
+
+    if (vring_idx & 1) {
+        vq = &vr_dpdk_virtio_rxqs[vif_idx][vring_idx/2];
+    } else {
+        vq = &vr_dpdk_virtio_txqs[vif_idx][vring_idx/2];
+    }
+
+    if (vq->vdv_used) {
+        /* Reading base index from the shared memory. */
+        if (vq->vdv_last_used_idx != vq->vdv_used->idx) {
+            RTE_LOG(INFO, UVHOST, "    recovering vring base %d -> %d\n",
+                    vq->vdv_last_used_idx, vq->vdv_used->idx);
+            vr_dpdk_virtio_set_vring_base(vif_idx, vring_idx, vq->vdv_used->idx);
+        }
+    }
+
+    return 0;
+}
+
+/*
+ * vr_dpdk_set_vring_addr - Sets the address of the virtio descriptor and
  * available/used rings based on messages sent by the vhost client.
  *
- * Returns 0 on suucess, -1 otherwise.
+ * Returns 0 on success, -1 otherwise.
  */
 int
 vr_dpdk_set_vring_addr(unsigned int vif_idx, unsigned int vring_idx,

dpdk/vr_dpdk_virtio.h

@@ -75,6 +75,7 @@ int vr_dpdk_virtio_set_vring_base(unsigned int vif_idx, unsigned int vring_idx,
                                    unsigned int vring_base);
 int vr_dpdk_virtio_get_vring_base(unsigned int vif_idx, unsigned int vring_idx,
                                   unsigned int *vring_basep);
+int vr_dpdk_virtio_recover_vring_base(unsigned int vif_idx, unsigned int vring_idx);
 int vr_dpdk_set_vring_addr(unsigned int vif_idx, unsigned int vring_idx,
                            struct vring_desc *vrucv_desc,
                            struct vring_avail *vrucv_avail,

dpdk/vr_uvhost.c

@@ -5,8 +5,6 @@
  * Copyright (c) 2014 Juniper Networks, Inc. All rights reserved.
  */
 
-#include <sys/poll.h>
-
 #include "vr_dpdk.h"
 #include "vr_dpdk_usocket.h"
 #include "vr_uvhost.h"

dpdk/vr_uvhost_client.c

@@ -7,6 +7,7 @@
 
 #include "vr_dpdk.h"
 #include "vr_uvhost_client.h"
+#include "vr_uvhost_util.h"
 
 static vr_uvh_client_t vr_uvh_clients[VR_UVH_MAX_CLIENTS];
 
@@ -57,9 +58,9 @@ vr_uvhost_new_client(int fd, char *path, int cidx)
 void
 vr_uvhost_del_client(vr_uvh_client_t *vru_cl)
 {
-    if (vru_cl->vruc_fd > 0) {
-        close(vru_cl->vruc_fd);
-    }
+    /* Remove both the socket we listen for and the socket we have accepted */
+    vr_uvhost_del_fds_by_arg(vru_cl);
+
     vru_cl->vruc_fd = -1;
     unlink(vru_cl->vruc_path);