client: fire the finish_cap_snap() after buffer being flushed

When the inode has Fb cap and the used reference is none zero, the
cap snap flushing will be delayed, so we need to make sure it will
be invoked after the dirty buffer is flushed to osd.

Fixes: https://tracker.ceph.com/issues/48679
Signed-off-by: Xiubo Li <xiubli@redhat.com>
(cherry picked from commit a34d0c242a73d7c29956b6894a430d9979225632)

diff --git a/src/client/Client.cc b/src/client/Client.cc
index 8648f1cf85a015b9a909df99f4c2038c963fd68a..82c7cc5a6edf9bbf18183e9de59446e6219fc87c 100755 (executable)
--- a/src/client/Client.cc
+++ b/src/client/Client.cc
@@ -3202,7 +3202,7 @@ void Client::put_cap_ref(Inode *in, int cap)
     int put_nref = 0;
     int drop = last & ~in->caps_issued();
     if (in->snapid == CEPH_NOSNAP) {
-      if ((last & CEPH_CAP_FILE_WR) &&
+      if ((last & (CEPH_CAP_FILE_WR | CEPH_CAP_FILE_BUFFER)) &&
          !in->cap_snaps.empty() &&
          in->cap_snaps.rbegin()->second.writing) {
        ldout(cct, 10) << __func__ << " finishing pending cap_snap on " << *in << dendl;
@@ -3725,6 +3725,7 @@ void Client::finish_cap_snap(Inode *in, CapSnap &capsnap, int used)
   }
 
   if (used & CEPH_CAP_FILE_BUFFER) {
+    capsnap.writing = 1;
     ldout(cct, 10) << __func__ << " " << *in << " cap_snap " << &capsnap << " used " << used
             << " WRBUFFER, delaying" << dendl;
   } else {
@@ -3800,7 +3801,7 @@ void Client::flush_snaps(Inode *in)
             << " on " << *in << dendl;
     if (capsnap.dirty_data || capsnap.writing)
       break;
-    
+
     capsnap.flush_tid = ++last_flush_tid;
     session->flushing_caps_tids.insert(capsnap.flush_tid);
     in->flushing_cap_tids[capsnap.flush_tid] = 0;