[Qemu-devel] [PATCH v5 0/6] fw_cfg: spec update, misc. cleanup, optimize read

[Gabriel L. Somlo]

New since v4:

        - Patch 5: Protect against (undefined) left-shifting a uint64_t
          by 64 bits

        - Patches 4 & 5: Reworked comment and commit blurb wording

Laszlo, thanks again for the thorough review (and the "C master class") :)

Regards,
  --Gabriel

>New since v3:
>
>        - Patches 1..3 unchanged
>
>        - Inserted new patch at position #4: avoid calculating an entry
>          pointer for the current item when s->cur_entry is FW_CFG_INVALID
>
>        - Patch 5 (formerly #4) now has the generic read method correctly
>          shift-left (adding 0 padding on the right) in the event that the
>          current item payload is exhausted in the course of a multi-byte
>          read operation (Laszlo, thanks again for catching that!)
>
>        - Patch 6 (formerly #5) is a rebased version of its former self,
>          but with no actual significant modifications.
>
>>New since v2:
>>
>>        - Patches 1-3: updated to address Laszlo's suggestions for better
>>          and more accurate change descriptions in commit logs, comments,
>>          etc.
>>
>>        - Patch 4: Per Laszlo's recommendation, this has been split into
>>          two separate components for improved legibility:
>>
>>                - Patch 4/5: Introduces the new generic read method, and
>>                  replaces the existing MMIO logic
>>
>>                - Patch 5/5: Replaces the IOPort read logic, and cleans
>>                  up the remaining unused bits of code.
>>
>>>This series' main purpose is to update (and simplify) the specified
>>>read callback behavior. An earlier standalone patch to move qemu function
>>>call API documentation into fw_cfg.h should logically be part of the series.
>>>
>>>Here's the summary of what each patch does:
>>>
>>>        - Patch 1/4 is an updated version of the standalone v1 patch
>>>          I sent out earlier; it moves all the qemu-internal host-side
>>>          function call api documentation out of docs/specs/fw_cfg.txt,
>>>          and into the fw_cfg.h header file, next to the prototype of
>>>          each documented api function.
>>>
>>>        - Patch 2/4 modifies the specified behavior of read callbacks
>>>          (from being invoked once per byte read, to being invoked once,
>>>           before ANY data is read, specifically once each time an item
>>>           is selected).
>>>
>>>        - Patch 3/4 additionally removes the now-redundant offset argument
>>>          from the read callback prototype.
>>>
>>>        - Finally, 4/4 consolidates (non-DMA) reads, minimizing the number
>>>          of times redundant sanity checks are performed, particularly for
>>>          wide (> byte) sized reads.

Gabriel L. Somlo (6):
  fw_cfg: move internal function call docs to header file
  fw_cfg: amend callback behavior spec to once per select
  fw_cfg: remove offset argument from callback prototype
  fw_cfg: avoid calculating invalid current entry pointer
  fw_cfg: add generic non-DMA read method
  fw_cfg: replace ioport data read with generic method

 docs/specs/fw_cfg.txt     |  85 +-----------------------------
 hw/arm/virt-acpi-build.c  |   2 +-
 hw/i386/acpi-build.c      |   2 +-
 hw/nvram/fw_cfg.c         |  75 +++++++++++++--------------
 include/hw/nvram/fw_cfg.h | 128 +++++++++++++++++++++++++++++++++++++++++++++-
 trace-events              |   2 +-
 6 files changed, 166 insertions(+), 128 deletions(-)

-- 
2.4.3