Re: [PATCH #upstream-fixes 2/4] libata: beef up iterators

[Mark Lord <liml@rtr.ca>]

Jeff Garzik wrote:
> Tejun Heo wrote:
>> There currently are the following loop constructs.
>>
>> * __ata_port_for_each_link() for all available links
>> * ata_port_for_each_link() for edge links
>> * ata_link_for_each_dev() for all devices
>> * ata_link_for_each_dev_reverse() for all devices in reverse order
>>
>> Now there's a need for loop construct which is similar to
>> __ata_port_for_each_link() but iterates over PMP links before the host
>> link.  Instead of adding another one with long name, do the following
>> cleanup.
>>
>> * Implement and export ata_link_next() and ata_dev_next() which take
>>   @mode parameter and can be used to build custom loop.
>> * Implement ata_for_each_link() and ata_for_each_dev() which take
>>   looping mode explicitly.
>>
>> The following iteration modes are implemented.
>>
>> * ATA_LITER_EDGE        : loop over edge links
>> * ATA_LITER_HOST_FIRST        : loop over all links, host link first
>> * ATA_LITER_PMP_FIRST        : loop over all links, PMP links first
>>
>> * ATA_DITER_ENABLED        : loop over enabled devices
>> * ATA_DITER_ENABLED_REVERSE    : loop over enabled devices in reverse 
>> order
>> * ATA_DITER_ALL            : loop over all devices
>> * ATA_DITER_ALL_REVERSE        : loop over all devices in reverse order
>>
>> This change removes exlicit device enabledness checks from many loops
>> and makes it clear which ones are iterated over in which direction.
>>
>> Signed-off-by: Tejun Heo <tj@kernel.org>
>> ---
>>  drivers/ata/ahci.c           |    8 -
>>  drivers/ata/ata_generic.c    |    5 -
>>  drivers/ata/libata-acpi.c    |   19 +---
>>  drivers/ata/libata-core.c    |  183 
>> ++++++++++++++++++++++++++++---------------
>>  drivers/ata/libata-eh.c      |   84 ++++++++-----------
>>  drivers/ata/libata-pmp.c     |   22 ++---
>>  drivers/ata/libata-scsi.c    |   22 ++---
>>  drivers/ata/pata_it821x.c    |   34 +++----
>>  drivers/ata/pata_ixp4xx_cf.c |   14 +--
>>  drivers/ata/pata_legacy.c    |   17 +--
>>  drivers/ata/pata_pdc2027x.c  |   27 ++----
>>  drivers/ata/pata_platform.c  |   14 +--
>>  drivers/ata/pata_rz1000.c    |   16 +--
>>  drivers/ata/sata_sil.c       |    2  include/linux/libata.h       |   
>> 50 +++++++----
>>  15 files changed, 279 insertions(+), 238 deletions(-)
> 
> ACK... for 2.6.29.  I think this is too much change for -rc2.  It's a 
> good idea though.
> 
> Also, it could use more documentation than just the commit message... 
> something that programmers can easily refer to (header file comment?)
..

Yeah.  Especially a reminder of what "LITER" and "DITER" stand for!  :)

Cheers