Merge remote-tracking branch 'remotes/stefanha/tags/block-pull-request' into staging

Pull request

 * Add 'drop-cache=on|off' option to file-posix.c.  The default is on.
   Disabling the option fixes a QEMU 3.0.0 performance regression when live
   migrating on the same host with cache.direct=off.

# gpg: Signature made Wed 13 Mar 2019 11:07:48 GMT
# gpg:                using RSA key 9CA4ABB381AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>" [full]
# gpg:                 aka "Stefan Hajnoczi <stefanha@gmail.com>" [full]
# Primary key fingerprint: 8695 A8BF D3F9 7CDA AC35  775A 9CA4 ABB3 81AB 73C8

* remotes/stefanha/tags/block-pull-request:
  file-posix: add drop-cache=on|off option

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

diff --cc block/file-posix.c
index e9fa6aa,936dea8..d102f3b
--- 1/block/file-posix.c
--- 2/block/file-posix.c
+++ b/block/file-posix.c
@@@ -976,7 -955,9 +987,8 @@@ static void raw_reopen_commit(BDRVReope
  {
      BDRVRawReopenState *rs = state->opaque;
      BDRVRawState *s = state->bs->opaque;
 -    Error *local_err = NULL;
  
+     s->drop_cache = rs->drop_cache;
      s->check_cache_dropped = rs->check_cache_dropped;
      s->open_flags = rs->open_flags;
  

diff --cc qapi/block-core.json
Simple merge