Merge branch 'next'

Pull in fixes for 3567 and 3524

3 files changed, 44 insertions, 11 deletions

diff --git a/src/librbd/AioCompletion.cc b/src/librbd/AioCompletion.cc
index 082a08eb651..86b5b504ebd 100644
--- a/src/librbd/AioCompletion.cc
+++ b/src/librbd/AioCompletion.cc
@@ -88,10 +88,11 @@ namespace librbd {
       if (m_req->m_ext_map.empty())
 	m_req->m_ext_map[m_req->m_object_off] = m_req->data().length();
 
-      m_completion->destriper.add_partial_sparse_result(m_cct,
-							m_req->data(),
-							m_req->m_ext_map, m_req->m_object_off,
-							m_req->m_buffer_extents);
+      m_completion->lock.Lock();
+      m_completion->destriper.add_partial_sparse_result(
+	  m_cct, m_req->data(), m_req->m_ext_map, m_req->m_object_off,
+	  m_req->m_buffer_extents);
+      m_completion->lock.Unlock();
       r = m_req->m_object_len;
     }
     m_completion->complete_request(m_cct, r);
diff --git a/src/librbd/AioRequest.cc b/src/librbd/AioRequest.cc
index 63424e397fc..b9a76e48e0a 100644
--- a/src/librbd/AioRequest.cc
+++ b/src/librbd/AioRequest.cc
@@ -157,15 +157,47 @@ namespace librbd {
       ldout(m_ictx->cct, 20) << "WRITE_CHECK_GUARD" << dendl;
 
       if (r == -ENOENT) {
+
 	Mutex::Locker l(m_ictx->snap_lock);
 	Mutex::Locker l2(m_ictx->parent_lock);
 
-	// copyup the entire object up to the overlap point
-	ldout(m_ictx->cct, 20) << "reading from parent " << m_object_image_extents << dendl;
-	assert(m_object_image_extents.size());
-
-	m_state = LIBRBD_AIO_WRITE_COPYUP;
-	read_from_parent(m_object_image_extents);
+	/*
+	 * Parent may have disappeared; if so, recover by using
+	 * send_copyup() to send the original write req (the copyup
+	 * operation itself will be a no-op, since someone must have
+	 * populated the child object while we weren't looking).
+	 * Move to WRITE_FLAT state as we'll be done with the
+	 * operation once the null copyup completes.
+	 */
+
+	if (m_ictx->parent == NULL) {
+	  ldout(m_ictx->cct, 20) << "parent is gone; do null copyup " << dendl;
+	  m_state = LIBRBD_AIO_WRITE_FLAT;
+	  send_copyup();
+	  finished = false;
+	  break;
+	}
+
+	// If parent still exists, overlap might also have changed.
+	uint64_t newlen = m_ictx->prune_parent_extents(
+	  m_object_image_extents, m_ictx->parent_md.overlap);
+
+	// copyup the entire object up to the overlap point, if any
+	if (newlen != 0) {
+	  ldout(m_ictx->cct, 20) << "should_complete(" << this << ") overlap "
+				 << m_ictx->parent_md.overlap << " newlen "
+				 << newlen << " image_extents"
+				 << m_object_image_extents << dendl;
+
+	  m_state = LIBRBD_AIO_WRITE_COPYUP;
+	  read_from_parent(m_object_image_extents);
+	} else {
+	  ldout(m_ictx->cct, 20) << "should_complete(" << this
+				 << "): parent overlap now 0" << dendl;
+	  m_object_image_extents.clear();
+	  m_state = LIBRBD_AIO_WRITE_FLAT;
+	  send_copyup();
+	}
 	finished = false;
 	break;
       }
diff --git a/src/osdc/Striper.cc b/src/osdc/Striper.cc
index 26e2b917bb7..7b5a402893f 100644
--- a/src/osdc/Striper.cc
+++ b/src/osdc/Striper.cc
@@ -284,7 +284,7 @@ void Striper::StripedReadResult::assemble_result(CephContext *cct, bufferlist& b
     size_t len = p->second.first.length();
     if (len < p->second.second) {
       if (zero_tail || bl.length()) {
-	bufferptr bp(p->second.second - p->second.first.length());
+	bufferptr bp(p->second.second - len);
 	bp.zero();
 	bl.push_front(bp);
 	bl.claim_prepend(p->second.first);