[SERVER] Segfault on conf reload (hopefully!) fixed

6 files changed, 41 insertions, 30 deletions

diff --git a/src/kernel/net.c b/src/kernel/net.c
index baa2966..bdab8c2 100644
--- a/src/kernel/net.c
+++ b/src/kernel/net.c
@@ -219,19 +219,6 @@ int dnbd3_net_discover(void *data)
                 continue;
             }
 
-            // panic mode, take first responding server
-            if (dev->panic)
-            {
-                printk("WARN: Panic mode, taking server %s\n", current_server);
-                sock_release(sock);
-                kfree(buf);
-                dev->thread_discover = NULL;
-                dnbd3_net_disconnect(dev);
-                strcpy(dev->cur_server.host, current_server);
-                dnbd3_net_connect(dev);
-                return 0;
-            }
-
             // Request filesize
             dnbd3_request.cmd = CMD_GET_SIZE;
             dnbd3_request.vid = dev->vid;
@@ -253,6 +240,19 @@ int dnbd3_net_discover(void *data)
             if (kernel_recvmsg(sock, &msg, &iov, 1, dnbd3_reply.size, msg.msg_flags) <= 0)
                 goto error;
 
+            // panic mode, take first responding server
+            if (dev->panic)
+            {
+                printk("WARN: Panic mode, taking server %s\n", current_server);
+                sock_release(sock);
+                kfree(buf);
+                dev->thread_discover = NULL;
+                dnbd3_net_disconnect(dev);
+                strcpy(dev->cur_server.host, current_server);
+                dnbd3_net_connect(dev);
+                return 0;
+            }
+
             do_gettimeofday(&start); // start rtt measurement
 
             // Request block
@@ -295,7 +295,7 @@ int dnbd3_net_discover(void *data)
             continue;
 
             error:
-                printk("ERROR: kernel_sendmsg or kernel_recvmsg (discover)\n");
+                printk("ERROR: Send/Receive failed, host %s:%s (discover)\n", current_server, dev->cur_server.port);
                 sock_release(sock);
                 sock = NULL;
                 continue;
diff --git a/src/server/ipc.c b/src/server/ipc.c
index bc7b7a5..522c4ca 100644
--- a/src/server/ipc.c
+++ b/src/server/ipc.c
@@ -95,6 +95,7 @@ void* dnbd3_ipc_receive()
             break;
 
         case IPC_INFO:
+            pthread_spin_lock(&_spinlock);
             num = g_slist_length(_dnbd3_clients) + _num_images +4;
             send(client_sock, &num, sizeof(int), MSG_WAITALL); // send number of lines to print
 
@@ -128,6 +129,7 @@ void* dnbd3_ipc_receive()
             sprintf(buf, "\nNumber clients: %i\n\n", g_slist_length(_dnbd3_clients));
             send(client_sock, buf, sizeof(buf), MSG_WAITALL);
 
+            pthread_spin_unlock(&_spinlock);
             close(client_sock);
             break;
 
diff --git a/src/server/net.c b/src/server/net.c
index 67a64c9..79bf28c 100644
--- a/src/server/net.c
+++ b/src/server/net.c
@@ -40,6 +40,7 @@ void *dnbd3_handle_query(void *dnbd3_client)
     dnbd3_request_t request;
     dnbd3_reply_t reply;
 
+    dnbd3_image_t *image = NULL;
     int image_file = -1;
 
     struct in_addr server;
@@ -51,6 +52,7 @@ void *dnbd3_handle_query(void *dnbd3_client)
         reply.error = 0;
         memcpy(reply.handle, request.handle, sizeof(request.handle));
 
+        pthread_spin_lock(&client->spinlock);
         switch (request.cmd)
         {
         case CMD_GET_SERVERS:
@@ -59,10 +61,9 @@ void *dnbd3_handle_query(void *dnbd3_client)
                 reply.size = 0;
                 reply.error = ERROR_RELOAD;
                 send(client->sock, (char *) &reply, sizeof(dnbd3_reply_t), 0);
-                continue;
+                break;
             }
 
-            pthread_spin_lock(&client->spinlock);
             if (client->image->num_servers < NUMBER_SERVERS)
                 reply.size = client->image->num_servers * sizeof(struct in_addr);
             else
@@ -75,13 +76,10 @@ void *dnbd3_handle_query(void *dnbd3_client)
                 inet_aton(client->image->servers[i], &server);
                 send(client->sock, (char *) &server, sizeof(struct in_addr), 0);
             }
-            pthread_spin_unlock(&client->spinlock);
-            continue;
+            break;
 
         case CMD_GET_SIZE:
-            pthread_spin_lock(&client->spinlock);
-            dnbd3_image_t *image = dnbd3_get_image(request.vid, request.rid);
-            pthread_spin_unlock(&client->spinlock);
+            image = dnbd3_get_image(request.vid, request.rid);
 
             if(!image)
             { // image not found, send error
@@ -89,7 +87,7 @@ void *dnbd3_handle_query(void *dnbd3_client)
                 reply.size = 0;
                 reply.error = ERROR_SIZE;
                 send(client->sock, (char *) &reply, sizeof(dnbd3_reply_t), 0);
-                continue;
+                break;
             }
 
             image_file = open(image->file, O_RDONLY);
@@ -100,11 +98,11 @@ void *dnbd3_handle_query(void *dnbd3_client)
             send(client->sock, (char *) &reply, sizeof(dnbd3_reply_t), 0);
             send(client->sock, &image->filesize, sizeof(uint64_t), 0);
             image->atime = time(NULL);
-            continue;
+            break;
 
         case CMD_GET_BLOCK:
             if (image_file < 0)
-                continue;
+                break;
 
             reply.size = request.size;
             send(client->sock, (char *) &reply, sizeof(dnbd3_reply_t), 0);
@@ -113,19 +111,20 @@ void *dnbd3_handle_query(void *dnbd3_client)
                 printf("ERROR: sendfile returned -1\n");
 
             image->atime = time(NULL); // TODO: check if mutex is needed
-
-            continue;
+            break;
 
         default:
             printf("ERROR: Unknown command\n");
-            continue;
+            break;
 
         }
-
+        pthread_spin_unlock(&client->spinlock);
     }
     close(client->sock);
     close(image_file);
+    pthread_spin_lock(&_spinlock);
     _dnbd3_clients = g_slist_remove(_dnbd3_clients, client);
+    pthread_spin_unlock(&_spinlock);
     printf("INFO: Client %s exit\n", client->ip);
     free(client);
     pthread_exit((void *) 0);
@@ -157,7 +156,7 @@ int dnbd3_setup_socket()
     }
 
     // Listen on socket
-    if (listen(sock, 50) == -1)
+    if (listen(sock, 100) == -1)
     {
         printf("ERROR: Listen failure\n");
         return -1;
diff --git a/src/server/server.c b/src/server/server.c
index dba7cdd..48dd545 100644
--- a/src/server/server.c
+++ b/src/server/server.c
@@ -35,6 +35,7 @@
 #include "ipc.h"
 
 int _sock;
+pthread_spinlock_t _spinlock;
 
 GSList *_dnbd3_clients = NULL;
 char *_config_file_name = DEFAULT_SERVER_CONFIG_FILE;
@@ -64,6 +65,8 @@ void dnbd3_print_version()
 void dnbd3_cleanup()
 {
     printf("INFO: Cleanup...\n");
+
+    pthread_spin_lock(&_spinlock);
     GSList *iterator = NULL;
     for (iterator = _dnbd3_clients; iterator; iterator = iterator->next)
     {
@@ -71,8 +74,8 @@ void dnbd3_cleanup()
         shutdown(client->sock, SHUT_RDWR);
         pthread_join(*client->thread, NULL);
     }
-
     g_slist_free(_dnbd3_clients);
+    pthread_spin_unlock(&_spinlock);
 
     close(_sock);
     free(_images);
@@ -158,6 +161,8 @@ int main(int argc, char* argv[])
     pthread_t thread_ipc;
     pthread_create(&(thread_ipc), NULL, dnbd3_ipc_receive, NULL);
 
+    pthread_spin_init(&_spinlock, PTHREAD_PROCESS_PRIVATE);
+
     printf("INFO: Server is ready...\n");
 
     // main loop
@@ -182,7 +187,9 @@ int main(int argc, char* argv[])
         dnbd3_client->thread = &thread;
         dnbd3_client->image = NULL;
 
+        pthread_spin_lock(&_spinlock);
         _dnbd3_clients = g_slist_append(_dnbd3_clients, dnbd3_client);
+        pthread_spin_unlock(&_spinlock);
 
         pthread_create(&(thread), NULL, dnbd3_handle_query, (void *) (uintptr_t) dnbd3_client);
         pthread_detach(thread);
diff --git a/src/server/server.h b/src/server/server.h
index 00a04e8..e73c171 100644
--- a/src/server/server.h
+++ b/src/server/server.h
@@ -49,6 +49,7 @@ typedef struct
 } dnbd3_client_t;
 
 extern GSList *_dnbd3_clients;
+extern pthread_spinlock_t _spinlock;
 extern char *_config_file_name;
 extern dnbd3_image_t *_images;
 extern size_t _num_images;
diff --git a/src/server/utils.c b/src/server/utils.c
index 70e195e..eda6216 100644
--- a/src/server/utils.c
+++ b/src/server/utils.c
@@ -74,6 +74,7 @@ void dnbd3_load_config(char *file)
 
 void dnbd3_reload_config(char* config_file_name)
 {
+    pthread_spin_lock(&_spinlock);
     GSList *iterator = NULL;
     for (iterator = _dnbd3_clients; iterator; iterator = iterator->next)
     {
@@ -89,6 +90,7 @@ void dnbd3_reload_config(char* config_file_name)
         dnbd3_client_t *client = iterator->data;
         pthread_spin_unlock(&client->spinlock);
     }
+    pthread_spin_unlock(&_spinlock);
 }
 
 dnbd3_image_t* dnbd3_get_image(int vid, int rid)