librbd: hide ENOENT on discard

AioZero, Truncate, and Remove are only used by discard and resize
operations where ENOENT can be safely ignored.  If that changes in the
future, we'll need to move the enoent flag setting into discard explicitly.

Fixes: #2958
Signed-off-by: Sage Weil <sage@inktank.com>

diff --git a/src/librbd/AioRequest.cc b/src/librbd/AioRequest.cc
index 44012c3619b441d2f9ae204bc287cb48639348bd..610fe63b9bb8df2a0ca80c1dc8b4007300fedf12 100644 (file)
--- a/src/librbd/AioRequest.cc
+++ b/src/librbd/AioRequest.cc
@@ -21,7 +21,8 @@ namespace librbd {
   AioRequest::AioRequest(ImageCtx *ictx, const std::string &oid,
                         uint64_t image_ofs, size_t len,
                         librados::snap_t snap_id,
-                        Context *completion) {
+                        Context *completion,
+                        bool hide_enoent) {
     m_ictx = ictx;
     m_ioctx.dup(ictx->data_ctx);
     m_ioctx.snap_set_read(snap_id);
@@ -32,6 +33,7 @@ namespace librbd {
     m_snap_id = snap_id;
     m_completion = completion;
     m_parent_completion = NULL;
+    m_hide_enoent = hide_enoent;
   }
 
   AioRequest::~AioRequest() {
@@ -97,8 +99,9 @@ namespace librbd {
   AbstractWrite::AbstractWrite(ImageCtx *ictx, const std::string &oid,
                               uint64_t image_ofs, size_t len,
                               librados::snap_t snap_id, Context *completion,
-                              bool has_parent, const ::SnapContext &snapc)
-    : AioRequest(ictx, oid, image_ofs, len, snap_id, completion)
+                              bool has_parent, const ::SnapContext &snapc,
+                              bool hide_enoent)
+    : AioRequest(ictx, oid, image_ofs, len, snap_id, completion, hide_enoent)
   {
     m_state = LIBRBD_AIO_WRITE_FINAL;
     m_has_parent = has_parent;

diff --git a/src/librbd/AioRequest.h b/src/librbd/AioRequest.h
index 4b90c6d3d8f06f28406fdad652eaac3144026ea5..79f0c5540b3bb505b64c72aa82d52d24d878a13d 100644 (file)
--- a/src/librbd/AioRequest.h
+++ b/src/librbd/AioRequest.h
@@ -27,7 +27,8 @@ namespace librbd {
   public:
     AioRequest();
     AioRequest(ImageCtx *ictx, const std::string &oid, uint64_t image_ofs,
-              size_t len, librados::snap_t snap_id, Context *completion);
+              size_t len, librados::snap_t snap_id, Context *completion,
+              bool hide_enoent);
     virtual ~AioRequest();
 
     uint64_t offset()
@@ -43,6 +44,8 @@ namespace librbd {
     void complete(int r)
     {
       if (should_complete(r)) {
+       if (m_hide_enoent && r == -ENOENT)
+         r = 0;
        m_completion->complete(r);
        delete this;
       }
@@ -64,6 +67,7 @@ namespace librbd {
     Context *m_completion;
     AioCompletion *m_parent_completion;
     ceph::bufferlist m_read_data;
+    bool m_hide_enoent;
   };
 
   class AioRead : public AioRequest {
@@ -71,7 +75,7 @@ namespace librbd {
     AioRead(ImageCtx *ictx, const std::string &oid, uint64_t image_ofs,
            size_t len, librados::snap_t snap_id, bool sparse,
            Context *completion)
-      : AioRequest(ictx, oid, image_ofs, len, snap_id, completion),
+      : AioRequest(ictx, oid, image_ofs, len, snap_id, completion, false),
        m_tried_parent(false), m_sparse(sparse) {
       m_ioctx.snap_set_read(m_snap_id);
     }
@@ -97,7 +101,7 @@ namespace librbd {
     AbstractWrite();
     AbstractWrite(ImageCtx *ictx, const std::string &oid, uint64_t image_ofs,
                  size_t len, librados::snap_t snap_id, Context *completion,
-                 bool has_parent, const ::SnapContext &snapc);
+                 bool has_parent, const ::SnapContext &snapc, bool hide_enoent);
     virtual ~AbstractWrite() {}
     virtual bool should_complete(int r);
     virtual int send();
@@ -144,7 +148,7 @@ namespace librbd {
             const ceph::bufferlist &data, const ::SnapContext &snapc,
             librados::snap_t snap_id, bool has_parent, Context *completion)
       : AbstractWrite(ictx, oid, image_ofs, data.length(), snap_id, completion,
-                     has_parent, snapc),
+                     has_parent, snapc, false),
        m_write_data(data) {
       guard_write();
       m_write.write(m_block_ofs, data);
@@ -166,7 +170,7 @@ namespace librbd {
              const ::SnapContext &snapc, librados::snap_t snap_id,
              bool has_parent, Context *completion)
       : AbstractWrite(ictx, oid, image_ofs, 0, snap_id, completion,
-                     has_parent, snapc) {
+                     has_parent, snapc, true) {
       if (has_parent)
        m_write.truncate(0);
       else
@@ -187,7 +191,7 @@ namespace librbd {
                const ::SnapContext &snapc, librados::snap_t snap_id,
                bool has_parent, Context *completion)
       : AbstractWrite(ictx, oid, image_ofs, 0, snap_id, completion,
-                has_parent, snapc) {
+                     has_parent, snapc, true) {
       guard_write();
       m_write.truncate(m_block_ofs);
     }
@@ -205,7 +209,7 @@ namespace librbd {
            size_t len, const ::SnapContext &snapc, librados::snap_t snap_id,
            bool has_parent, Context *completion)
       : AbstractWrite(ictx, oid, image_ofs, len, snap_id, completion,
-                     has_parent, snapc) {
+                     has_parent, snapc, true) {
       guard_write();
       m_write.zero(m_block_ofs, len);
     }