[PATCH v2 0/7] block-copy: protect block-copy internal structures

[Emanuele Giuseppe Esposito <eesposit@redhat.com>]

This serie of patches aims to reduce the usage of the global
AioContexlock in block-copy, by introducing smaller granularity
locks thus on making the block layer thread safe. 

This serie depends on Paolo's coroutine_sleep API and my previous
serie that brings thread safety to the smaller API used by block-copy,
like ratelimit, progressmeter abd co-shared-resource.

What's missing for block-copy to be fully thread-safe is fixing
the CoSleep API to allow cross-thread sleep and wakeup.
Paolo is working on it and will post the patches once his new
CoSleep API is accepted.

Patch 1 introduces the .method field instead of .use_copy_range
and .copy_size, so that it can be later used as atomic.
Patch 2-3 provide comments and refactoring in preparation to
the locks added in patch 4 on BlockCopyTask, patch 5-6 on
BlockCopyCallState and 7 BlockCopyState.

Based-on: <20210517100548.28806-1-pbonzini@redhat.com>
Based-on: <20210518094058.25952-1-eesposit@redhat.com>
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
---
v1 -> v2:
* More field categorized as IN/State/OUT in the various struct, better
  documentation in the structs
* Fix a couple of places where I missed locks [Vladimir, Paolo]


Emanuele Giuseppe Esposito (6):
  block-copy: improve documentation of BlockCopyTask and BlockCopyState
    types and functions
  block-copy: move progress_set_remaining in block_copy_task_end
  block-copy: add a CoMutex to the BlockCopyTask list
  block-copy: add QemuMutex lock for BlockCopyCallState list
  block-copy: atomic .cancelled and .finished fields in
    BlockCopyCallState
  block-copy: protect BlockCopyState .method fields

Paolo Bonzini (1):
  block-copy: streamline choice of copy_range vs. read/write

 block/block-copy.c | 234 +++++++++++++++++++++++++++++----------------
 1 file changed, 150 insertions(+), 84 deletions(-)

-- 
2.30.2