1 files changed, 25 insertions, 56 deletions

diff --git a/tools/virtiofsd/fuse_virtio.c b/tools/virtiofsd/fuse_virtio.c
index 9efdbd8ffd..fa4aff9b0e 100644
--- a/tools/virtiofsd/fuse_virtio.c
+++ b/tools/virtiofsd/fuse_virtio.c
@@ -366,14 +366,12 @@ int virtio_send_data_iov(struct fuse_session *se, struct fuse_chan *ch,
     if (in_len < sizeof(struct fuse_out_header)) {
         fuse_log(FUSE_LOG_ERR, "%s: elem %d too short for out_header\n",
                  __func__, elem->index);
-        ret = E2BIG;
-        goto err;
+        return E2BIG;
     }
     if (in_len < tosend_len) {
         fuse_log(FUSE_LOG_ERR, "%s: elem %d too small for data len %zd\n",
                  __func__, elem->index, tosend_len);
-        ret = E2BIG;
-        goto err;
+        return E2BIG;
     }
 
     /* TODO: Limit to 'len' */
@@ -389,68 +387,46 @@ int virtio_send_data_iov(struct fuse_session *se, struct fuse_chan *ch,
     memcpy(in_sg_cpy, in_sg, sizeof(struct iovec) * in_num);
     /* These get updated as we skip */
     struct iovec *in_sg_ptr = in_sg_cpy;
-    int in_sg_cpy_count = in_num;
+    unsigned int in_sg_cpy_count = in_num;
 
     /* skip over parts of in_sg that contained the header iov */
-    size_t skip_size = iov_len;
+    iov_discard_front(&in_sg_ptr, &in_sg_cpy_count, iov_len);
 
-    size_t in_sg_left = 0;
     do {
-        while (skip_size != 0 && in_sg_cpy_count) {
-            if (skip_size >= in_sg_ptr[0].iov_len) {
-                skip_size -= in_sg_ptr[0].iov_len;
-                in_sg_ptr++;
-                in_sg_cpy_count--;
-            } else {
-                in_sg_ptr[0].iov_len -= skip_size;
-                in_sg_ptr[0].iov_base += skip_size;
-                break;
-            }
-        }
+        fuse_log(FUSE_LOG_DEBUG, "%s: in_sg_cpy_count=%d len remaining=%zd\n",
+                 __func__, in_sg_cpy_count, len);
 
-        int i;
-        for (i = 0, in_sg_left = 0; i < in_sg_cpy_count; i++) {
-            in_sg_left += in_sg_ptr[i].iov_len;
-        }
-        fuse_log(FUSE_LOG_DEBUG,
-                 "%s: after skip skip_size=%zd in_sg_cpy_count=%d "
-                 "in_sg_left=%zd\n",
-                 __func__, skip_size, in_sg_cpy_count, in_sg_left);
         ret = preadv(buf->buf[0].fd, in_sg_ptr, in_sg_cpy_count,
                      buf->buf[0].pos);
 
         if (ret == -1) {
             ret = errno;
+            if (ret == EINTR) {
+                continue;
+            }
             fuse_log(FUSE_LOG_DEBUG, "%s: preadv failed (%m) len=%zd\n",
                      __func__, len);
-            goto err;
+            return ret;
         }
-        fuse_log(FUSE_LOG_DEBUG, "%s: preadv ret=%d len=%zd\n", __func__,
-                 ret, len);
-        if (ret < len && ret) {
-            fuse_log(FUSE_LOG_DEBUG, "%s: ret < len\n", __func__);
-            /* Skip over this much next time around */
-            skip_size = ret;
-            buf->buf[0].pos += ret;
-            len -= ret;
 
-            /* Lets do another read */
-            continue;
-        }
         if (!ret) {
             /* EOF case? */
-            fuse_log(FUSE_LOG_DEBUG, "%s: !ret in_sg_left=%zd\n", __func__,
-                     in_sg_left);
+            fuse_log(FUSE_LOG_DEBUG, "%s: !ret len remaining=%zd\n", __func__,
+                     len);
             break;
         }
-        if (ret != len) {
-            fuse_log(FUSE_LOG_DEBUG, "%s: ret!=len\n", __func__);
-            ret = EIO;
-            goto err;
-        }
-        in_sg_left -= ret;
+        fuse_log(FUSE_LOG_DEBUG, "%s: preadv ret=%d len=%zd\n", __func__,
+                 ret, len);
+
         len -= ret;
-    } while (in_sg_left);
+        /* Short read. Retry reading remaining bytes */
+        if (len) {
+            fuse_log(FUSE_LOG_DEBUG, "%s: ret < len\n", __func__);
+            /* Skip over this much next time around */
+            iov_discard_front(&in_sg_ptr, &in_sg_cpy_count, ret);
+            buf->buf[0].pos += ret;
+        }
+    } while (len);
 
     /* Need to fix out->len on EOF */
     if (len) {
@@ -460,21 +436,14 @@ int virtio_send_data_iov(struct fuse_session *se, struct fuse_chan *ch,
         out_sg->len = tosend_len;
     }
 
-    ret = 0;
-
     vu_dispatch_rdlock(qi->virtio_dev);
     pthread_mutex_lock(&qi->vq_lock);
     vu_queue_push(dev, q, elem, tosend_len);
     vu_queue_notify(dev, q);
     pthread_mutex_unlock(&qi->vq_lock);
     vu_dispatch_unlock(qi->virtio_dev);
-
-err:
-    if (ret == 0) {
-        req->reply_sent = true;
-    }
-
-    return ret;
+    req->reply_sent = true;
+    return 0;
 }
 
 static __thread bool clone_fs_called;