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

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

Pull request

# gpg: Signature made Fri 05 Jun 2020 10:47:27 BST
# gpg:                using RSA key 8695A8BFD3F97CDAAC35775A9CA4ABB381AB73C8
# 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:
  block: Factor out bdrv_run_co()
  exec: Rename qemu_ram_writeback() as qemu_ram_msync()
  hw/block: Let the NVMe emulated device be target-agnostic
  memory: Extract memory_region_msync() from memory_region_writeback()
  memory: Rename memory_region_do_writeback -> memory_region_writeback
  fuzz: run the main-loop in fork-server process
  fuzz: add mangled object name to linker script
  fuzz: fix typo in i440fx-qtest-reboot arguments
  fuzz: add datadir for oss-fuzz compatability
  io_uring: use io_uring_cq_ready() to check for ready cqes
  io_uring: retry io_uring_submit() if it fails with errno=EINTR

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