[Qemu-devel] [PATCH 05/25] nbd: Avoid generic -EINVAL

[Max Reitz <mreitz@redhat.com>]

Just returning -EINVAL for everything is bad. -EIO is often better, and
sometimes there is an even more fitting value.

Signed-off-by: Max Reitz <mreitz@redhat.com>
---
 nbd.c | 49 +++++++++++++++++++++++++------------------------
 1 file changed, 25 insertions(+), 24 deletions(-)

diff --git a/nbd.c b/nbd.c
index b4776ce..d2eb1c5 100644
--- a/nbd.c
+++ b/nbd.c
@@ -238,22 +238,22 @@ static int nbd_send_rep(int csock, uint32_t type, uint32_t opt)
     magic = cpu_to_be64(NBD_REP_MAGIC);
     if (write_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) {
         LOG("write failed (rep magic)");
-        return -EINVAL;
+        return -EIO;
     }
     opt = cpu_to_be32(opt);
     if (write_sync(csock, &opt, sizeof(opt)) != sizeof(opt)) {
         LOG("write failed (rep opt)");
-        return -EINVAL;
+        return -EIO;
     }
     type = cpu_to_be32(type);
     if (write_sync(csock, &type, sizeof(type)) != sizeof(type)) {
         LOG("write failed (rep type)");
-        return -EINVAL;
+        return -EIO;
     }
     len = cpu_to_be32(0);
     if (write_sync(csock, &len, sizeof(len)) != sizeof(len)) {
         LOG("write failed (rep data length)");
-        return -EINVAL;
+        return -EIO;
     }
     return 0;
 }
@@ -267,31 +267,31 @@ static int nbd_send_rep_list(int csock, NBDExport *exp)
     magic = cpu_to_be64(NBD_REP_MAGIC);
     if (write_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) {
         LOG("write failed (magic)");
-        return -EINVAL;
+        return -EIO;
      }
     opt = cpu_to_be32(NBD_OPT_LIST);
     if (write_sync(csock, &opt, sizeof(opt)) != sizeof(opt)) {
         LOG("write failed (opt)");
-        return -EINVAL;
+        return -EIO;
     }
     type = cpu_to_be32(NBD_REP_SERVER);
     if (write_sync(csock, &type, sizeof(type)) != sizeof(type)) {
         LOG("write failed (reply type)");
-        return -EINVAL;
+        return -EIO;
     }
     len = cpu_to_be32(name_len + sizeof(len));
     if (write_sync(csock, &len, sizeof(len)) != sizeof(len)) {
         LOG("write failed (length)");
-        return -EINVAL;
+        return -EIO;
     }
     len = cpu_to_be32(name_len);
     if (write_sync(csock, &len, sizeof(len)) != sizeof(len)) {
         LOG("write failed (length)");
-        return -EINVAL;
+        return -EIO;
     }
     if (write_sync(csock, exp->name, name_len) != name_len) {
         LOG("write failed (buffer)");
-        return -EINVAL;
+        return -EIO;
     }
     return 0;
 }
@@ -309,7 +309,7 @@ static int nbd_handle_list(NBDClient *client, uint32_t length)
     /* For each export, send a NBD_REP_SERVER reply. */
     QTAILQ_FOREACH(exp, &exports, next) {
         if (nbd_send_rep_list(csock, exp)) {
-            return -EINVAL;
+            return -EIO;
         }
     }
     /* Finish with a NBD_REP_ACK. */
@@ -331,6 +331,7 @@ static int nbd_handle_export_name(NBDClient *client, uint32_t length)
     }
     if (read_sync(csock, name, length) != length) {
         LOG("read failed");
+        rc = -EIO;
         goto fail;
     }
     name[length] = '\0';
@@ -376,22 +377,22 @@ static int nbd_receive_options(NBDClient *client)
 
         if (read_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) {
             LOG("read failed");
-            return -EINVAL;
+            return -EIO;
         }
         TRACE("Checking opts magic");
         if (magic != be64_to_cpu(NBD_OPTS_MAGIC)) {
             LOG("Bad magic received");
-            return -EINVAL;
+            return -EIO;
         }
 
         if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) {
             LOG("read failed");
-            return -EINVAL;
+            return -EIO;
         }
 
         if (read_sync(csock, &length, sizeof(length)) != sizeof(length)) {
             LOG("read failed");
-            return -EINVAL;
+            return -EIO;
         }
         length = be32_to_cpu(length);
 
@@ -404,7 +405,7 @@ static int nbd_receive_options(NBDClient *client)
             break;
 
         case NBD_OPT_ABORT:
-            return -EINVAL;
+            return -ECONNABORTED;
 
         case NBD_OPT_EXPORT_NAME:
             return nbd_handle_export_name(client, length);
@@ -446,7 +447,7 @@ static int nbd_send_negotiate(NBDClient *client)
      */
 
     qemu_set_block(csock);
-    rc = -EINVAL;
+    rc = -EIO;
 
     TRACE("Beginning negotiation.");
     memset(buf, 0, sizeof(buf));
@@ -503,7 +504,7 @@ int nbd_receive_negotiate(int csock, const char *name, uint32_t *flags,
 
     TRACE("Receiving negotiation.");
 
-    rc = -EINVAL;
+    rc = -EIO;
 
     if (read_sync(csock, buf, 8) != 8) {
         error_setg(errp, "Failed to read data");
@@ -752,7 +753,7 @@ ssize_t nbd_send_request(int csock, struct nbd_request *request)
 
     if (ret != sizeof(buf)) {
         LOG("writing to socket failed");
-        return -EINVAL;
+        return -EIO;
     }
     return 0;
 }
@@ -770,7 +771,7 @@ static ssize_t nbd_receive_request(int csock, struct nbd_request *request)
 
     if (ret != sizeof(buf)) {
         LOG("read failed");
-        return -EINVAL;
+        return -EIO;
     }
 
     /* Request
@@ -793,7 +794,7 @@ static ssize_t nbd_receive_request(int csock, struct nbd_request *request)
 
     if (magic != NBD_REQUEST_MAGIC) {
         LOG("invalid magic (got 0x%x)", magic);
-        return -EINVAL;
+        return -EIO;
     }
     return 0;
 }
@@ -811,7 +812,7 @@ ssize_t nbd_receive_reply(int csock, struct nbd_reply *reply)
 
     if (ret != sizeof(buf)) {
         LOG("read failed");
-        return -EINVAL;
+        return -EIO;
     }
 
     /* Reply
@@ -830,7 +831,7 @@ ssize_t nbd_receive_reply(int csock, struct nbd_reply *reply)
 
     if (magic != NBD_REPLY_MAGIC) {
         LOG("invalid magic (got 0x%x)", magic);
-        return -EINVAL;
+        return -EIO;
     }
     return 0;
 }
@@ -858,7 +859,7 @@ static ssize_t nbd_send_reply(int csock, struct nbd_reply *reply)
 
     if (ret != sizeof(buf)) {
         LOG("writing to socket failed");
-        return -EINVAL;
+        return -EIO;
     }
     return 0;
 }
-- 
2.1.0