[Qemu-devel] [PATCH 0/4] block: Drop BDS.filename

[Max Reitz <mreitz@redhat.com>]

The BDS filename field is generally only used when opening disk images
or emitting error or warning messages, the only exception to this rule
is the map command of qemu-img. However, using exact_filename there
instead should not be a problem. Therefore, we can drop the filename
field from the BlockDriverState and use a function instead which builds
the filename from scratch when called.

This is slower than reading a static char array but the problem of that
static array is that it may become obsolete due to changes in any
BlockDriverState or in the BDS graph. Using a function which rebuilds
the filename every time it is called resolves this problem.

The disadvantage of worse performance is negligible, on the other hand.
After patch 2 of this series, which replaces some queries of
BDS.filename by reads from somewhere else (mostly BDS.exact_filename),
the filename field is only used when a disk image is opened or some
message should be emitted, both of which cases do not suffer from the
performance hit.


Max Reitz (4):
  block: Change bdrv_get_encrypted_filename()
  block: Avoid BlockDriverState.filename
  block: Add bdrv_filename()
  block: Drop BlockDriverState.filename

 block.c                   | 90 ++++++++++++++++++++++++++++++++---------------
 block/commit.c            |  4 ++-
 block/gluster.c           |  2 +-
 block/mirror.c            | 14 +++++---
 block/qapi.c              |  7 ++--
 block/raw-posix.c         |  8 ++---
 block/raw-win32.c         |  4 +--
 block/vhdx-log.c          |  5 ++-
 block/vmdk.c              | 22 ++++++++----
 block/vpc.c               |  6 ++--
 blockdev.c                | 21 ++++++++---
 include/block/block.h     |  3 +-
 include/block/block_int.h |  1 -
 monitor.c                 |  7 ++--
 qemu-img.c                |  2 +-
 qmp.c                     |  4 ++-
 16 files changed, 136 insertions(+), 64 deletions(-)

-- 
2.1.0