[SERVER] Config reload fixed

1 files changed, 110 insertions, 100 deletions

diff --git a/src/kernel/net.c b/src/kernel/net.c
index 7afac7d..5bd8871 100644
--- a/src/kernel/net.c
+++ b/src/kernel/net.c
@@ -19,23 +19,25 @@
  */
 
 #include "net.h"
+#include "blk.h"
 #include "utils.h"
 
 void dnbd3_net_connect(dnbd3_device_t *dev)
 {
     struct sockaddr_in sin;
-    struct msghdr msg;
-    struct kvec iov;
-    dnbd3_request_t dnbd3_request;
-    dnbd3_reply_t dnbd3_reply;
-    uint64_t filesize;
+    struct request *req = kmalloc(sizeof(struct request), GFP_ATOMIC);
 
+    // do some checks before connecting
+    if (!req)
+    {
+        printk("ERROR: Kmalloc failed.\n");
+        return;
+    }
     if (!dev->host || !dev->port || (dev->vid == 0))
     {
         printk("ERROR: Host, port or vid not set.\n");
         return;
     }
-
     if (dev->sock)
     {
         printk("ERROR: Device %s already connected to %s.\n", dev->disk->disk_name, dev->host);
@@ -62,40 +64,6 @@ void dnbd3_net_connect(dnbd3_device_t *dev)
         return;
     }
 
-    // prepare message
-    dnbd3_request.cmd = CMD_GET_SIZE;
-    dnbd3_request.vid = dev->vid;
-    dnbd3_request.rid = dev->rid;
-    msg.msg_name = NULL;
-    msg.msg_namelen = 0;
-    msg.msg_control = NULL;
-    msg.msg_controllen = 0;
-    msg.msg_flags = MSG_WAITALL | MSG_NOSIGNAL; // No SIGPIPE
-
-    // send message
-    iov.iov_base = &dnbd3_request;
-    iov.iov_len = sizeof(dnbd3_request);
-    kernel_sendmsg(dev->sock, &msg, &iov, 1, sizeof(dnbd3_request));
-
-    // receive replay
-    iov.iov_base = &dnbd3_reply;
-    iov.iov_len = sizeof(dnbd3_reply);
-    kernel_recvmsg(dev->sock, &msg, &iov, 1, sizeof(dnbd3_reply), msg.msg_flags);
-    if (dnbd3_reply.size <= 0)
-    {
-        printk("ERROR: File size returned by server is < 0.\n");
-        sock_release(dev->sock);
-        dev->sock = NULL;
-        return;
-    }
-
-    // receive and set filesize
-    iov.iov_base = &filesize;
-    iov.iov_len = sizeof(uint64_t);
-    kernel_recvmsg(dev->sock, &msg, &iov, 1, dnbd3_reply.size, msg.msg_flags);
-    set_capacity(dev->disk, filesize >> 9); /* 512 Byte blocks */
-    printk("INFO: Filesize %s: %llu\n", dev->disk->disk_name, filesize);
-
     // start sending thread
     dev->thread_send = kthread_create(dnbd3_net_send, dev, dev->disk->disk_name);
     wake_up_process(dev->thread_send);
@@ -104,12 +72,18 @@ void dnbd3_net_connect(dnbd3_device_t *dev)
     dev->thread_receive = kthread_create(dnbd3_net_receive, dev, dev->disk->disk_name);
     wake_up_process(dev->thread_receive);
 
-    // Add heartbeat timer
+    // add heartbeat timer
     init_timer(&dev->hb_timer);
     dev->hb_timer.data = (unsigned long) dev;
     dev->hb_timer.function = dnbd3_net_heartbeat;
     dev->hb_timer.expires = jiffies + HB_INTERVAL;
     add_timer(&dev->hb_timer);
+
+    // enqueue request to request_queue_send (ask file size)
+    req->cmd_type = REQ_TYPE_SPECIAL;
+    req->cmd_flags = REQ_GET_FILESIZE;
+    list_add(&req->queuelist, &dev->request_queue_send);
+    wake_up(&dev->process_queue_send);
 }
 
 void dnbd3_net_disconnect(dnbd3_device_t *dev)
@@ -124,7 +98,7 @@ void dnbd3_net_disconnect(dnbd3_device_t *dev)
         kthread_stop(dev->thread_receive);
     }
 
-    // clear sock
+    // clear socket
     if (dev->sock)
     {
         sock_release(dev->sock);
@@ -151,17 +125,13 @@ void dnbd3_net_disconnect(dnbd3_device_t *dev)
 int dnbd3_net_send(void *data)
 {
     dnbd3_device_t *dev = data;
-    dnbd3_request_t dnbd3_request;
     struct request *blk_request;
+
+    dnbd3_request_t dnbd3_request;
     struct msghdr msg;
     struct kvec iov;
 
-    msg.msg_name = NULL;
-    msg.msg_namelen = 0;
-    msg.msg_control = NULL;
-    msg.msg_controllen = 0;
-    msg.msg_flags = MSG_WAITALL | MSG_NOSIGNAL; // No SIGPIPE
-
+    init_msghdr(msg);
     set_user_nice(current, -20);
 
     while (!kthread_should_stop() || !list_empty(&dev->request_queue_send))
@@ -178,31 +148,42 @@ int dnbd3_net_send(void *data)
         list_del_init(&blk_request->queuelist);
         spin_unlock_irq(&dev->blk_lock);
 
+        // what to do?
         switch (blk_request->cmd_type)
         {
-        case REQ_TYPE_SPECIAL:
-            dnbd3_request.cmd = CMD_GET_SERVERS;
-            break;
-
         case REQ_TYPE_FS:
             dnbd3_request.cmd = CMD_GET_BLOCK;
             dnbd3_request.offset = blk_rq_pos(blk_request) << 9; // *512
             dnbd3_request.size = blk_rq_bytes(blk_request); // bytes left to complete entire request
             break;
 
-        default:
-            printk("ERROR: Unknown command\n");
+        case REQ_TYPE_SPECIAL:
+            switch (blk_request->cmd_flags)
+            {
+            case REQ_GET_FILESIZE:
+                dnbd3_request.cmd = CMD_GET_SIZE;
+                dnbd3_request.vid = dev->vid;
+                dnbd3_request.rid = dev->rid;
+                break;
+            case REQ_GET_SERVERS:
+                dnbd3_request.cmd = CMD_GET_SERVERS;
+                break;
+            }
             break;
+
+        default:
+            printk("ERROR: Unknown command (Send)\n");
+            continue;
         }
 
+        // send net request
         memcpy(dnbd3_request.handle, &blk_request, sizeof(blk_request));
         iov.iov_base = &dnbd3_request;
         iov.iov_len = sizeof(dnbd3_request);
-
-        // send net request
         if (kernel_sendmsg(dev->sock, &msg, &iov, 1, sizeof(dnbd3_request)) <= 0)
             printk("ERROR: kernel_sendmsg\n");
 
+        // enqueue request to request_queue_receive
         spin_lock_irq(&dev->blk_lock);
         list_add_tail(&blk_request->queuelist, &dev->request_queue_receive);
         spin_unlock_irq(&dev->blk_lock);
@@ -214,27 +195,21 @@ int dnbd3_net_send(void *data)
 int dnbd3_net_receive(void *data)
 {
     dnbd3_device_t *dev = data;
+    struct request *blk_request, *tmp_request, *received_request;
+
     dnbd3_reply_t dnbd3_reply;
-    struct request *blk_request;
     struct msghdr msg;
     struct kvec iov;
     struct req_iterator iter;
     struct bio_vec *bvec;
+    void *kaddr;
     unsigned long flags;
     sigset_t blocked, oldset;
-    struct request *tmp_request, *received_request;
-    void *kaddr;
-    unsigned int size;
 
-    int i = 0;
-    //char a[15];
-
-    msg.msg_name = NULL;
-    msg.msg_namelen = 0;
-    msg.msg_control = NULL;
-    msg.msg_controllen = 0;
-    msg.msg_flags = MSG_WAITALL | MSG_NOSIGNAL; // No SIGPIPE
+    unsigned int size, i;
+    uint64_t filesize;
 
+    init_msghdr(msg);
     set_user_nice(current, -20);
 
     while (!kthread_should_stop() || !list_empty(&dev->request_queue_receive))
@@ -256,15 +231,67 @@ int dnbd3_net_receive(void *data)
         list_for_each_entry_safe(blk_request, tmp_request, &dev->request_queue_receive, queuelist)
         {
             if (blk_request != received_request)
-            continue;
+                continue;
 
             list_del_init(&blk_request->queuelist);
             break;
         }
         spin_unlock_irq(&dev->blk_lock);
 
+        // check if server send error
+        switch (dnbd3_reply.error)
+        {
+        case ERROR_SIZE:
+            printk("ERROR: Requested image does't exist\n");
+            kthread_stop(dev->thread_send);
+            del_timer(&dev->hb_timer);
+            sock_release(dev->sock);
+            kfree(blk_request);
+            dev->sock = NULL;
+            return -1;
+
+        case ERROR_RELOAD:
+            blk_request->cmd_type = REQ_TYPE_SPECIAL;
+            blk_request->cmd_flags = REQ_GET_FILESIZE;
+            list_add(&blk_request->queuelist, &dev->request_queue_send);
+            wake_up(&dev->process_queue_send);
+            continue;
+
+        }
+
+        // what to do?
         switch (dnbd3_reply.cmd)
         {
+        case CMD_GET_BLOCK:
+            // receive data and answer to block layer
+            rq_for_each_segment(bvec, blk_request, iter)
+            {
+                siginitsetinv(&blocked, sigmask(SIGKILL));
+                sigprocmask(SIG_SETMASK, &blocked, &oldset);
+
+                kaddr = kmap(bvec->bv_page) + bvec->bv_offset;
+                size = bvec->bv_len;
+                iov.iov_base = kaddr;
+                iov.iov_len = size;
+                kernel_recvmsg(dev->sock, &msg, &iov, 1, size, msg.msg_flags);
+                kunmap(bvec->bv_page);
+
+                sigprocmask(SIG_SETMASK, &oldset, NULL);
+            }
+            spin_lock_irqsave(&dev->blk_lock, flags);
+            __blk_end_request_all(blk_request, 0);
+            spin_unlock_irqrestore(&dev->blk_lock, flags);
+            continue;
+
+        case CMD_GET_SIZE:
+            iov.iov_base = &filesize;
+            iov.iov_len = sizeof(uint64_t);
+            kernel_recvmsg(dev->sock, &msg, &iov, 1, dnbd3_reply.size, msg.msg_flags);
+            set_capacity(dev->disk, filesize >> 9); /* 512 Byte blocks */
+            printk("INFO: Filesize %s: %llu\n", dev->disk->disk_name, filesize);
+            kfree(blk_request);
+            continue;
+
         case CMD_GET_SERVERS:
             dev->num_servers = dnbd3_reply.size / sizeof(struct in_addr);
             size = sizeof(struct in_addr);
@@ -273,38 +300,15 @@ int dnbd3_net_receive(void *data)
                 iov.iov_base = &dev->servers[i];
                 iov.iov_len = size;
                 kernel_recvmsg(dev->sock, &msg, &iov, 1, size, msg.msg_flags);
-
-//                inet_ntoa(dev->servers[i], a);
-//                printk("INFO: Server[%i] %s\n", i, a);
             }
-            break;
-
-        case CMD_GET_BLOCK:
-            // receive data and answer to block layer
-            rq_for_each_segment(bvec, blk_request, iter)
-                {
-                    siginitsetinv(&blocked, sigmask(SIGKILL));
-                    sigprocmask(SIG_SETMASK, &blocked, &oldset);
-
-                    kaddr = kmap(bvec->bv_page) + bvec->bv_offset;
-                    size = bvec->bv_len;
-                    iov.iov_base = kaddr;
-                    iov.iov_len = size;
-                    kernel_recvmsg(dev->sock, &msg, &iov, 1, size, msg.msg_flags);
-                    kunmap(bvec->bv_page);
-
-                    sigprocmask(SIG_SETMASK, &oldset, NULL);
-                }
-            spin_lock_irqsave(&dev->blk_lock, flags);
-            __blk_end_request_all(blk_request, 0);
-            spin_unlock_irqrestore(&dev->blk_lock, flags);
-            break;
+            kfree(blk_request);
+            continue;
 
         default:
-            printk("ERROR: Unknown command\n");
-            break;
-        }
+            printk("ERROR: Unknown command (Receive)\n");
+            continue;
 
+        }
     }
     return 0;
 }
@@ -312,8 +316,14 @@ int dnbd3_net_receive(void *data)
 void dnbd3_net_heartbeat(unsigned long arg)
 {
     dnbd3_device_t *dev = (dnbd3_device_t *) arg;
-    list_add(&dev->hb_request.queuelist, &dev->request_queue_send);
-    wake_up(&dev->process_queue_send);
+    struct request *req = kmalloc(sizeof(struct request), GFP_ATOMIC);
+    if (req)
+    {
+        req->cmd_type = REQ_TYPE_SPECIAL;
+        req->cmd_flags = REQ_GET_SERVERS;
+        list_add(&req->queuelist, &dev->request_queue_send);
+        wake_up(&dev->process_queue_send);
+    }
     dev->hb_timer.expires = jiffies + HB_INTERVAL;
     add_timer(&dev->hb_timer);
 }