[LTP] [PATCH] lib: tst_device: Allow more control over the device size

[Joerg Vehlow <lkml@jv-coder.de>]

Hi Cyril,

On 8/2/2021 2:14 PM, Cyril Hrubis wrote:
> Hi!
>> The usage of foo foo_ and foo__ does not really help in reading the code :)
>> There could also be some logic errors hiding, e.g.
>> tst_acquire_loop_device should probably not default to DEV_SIZE_MB at all.
>> The caller should be responsible for finding a correct size and the two
>> users of this function (tst_device [the binary] and
>> tst_acquire_device__) do pass a concrete value for size.
> Actually the tst_device binary does not pass a concrete size unless the
> shell code that calls it passes an optional parameter, so the fallback
> to DEV_SIZE_MB if size == 0 has to stay in the double underscore
> function. I will send a v2 that just replaces the second occurence of
> MAX() in tst_device.c for now as it looks to me that any singificant
> cleanup would require complete redesing of the interface and quite
> possibly rewrite of the last 16 tests that use the old API as a
> pre-requisite.
I think we maximized confusion.
I was not arguing about the defaulting to DEV_SIZE_MB in the double 
underscore function, but about the defaulting in the 
tst_acquire_loop_device function. This function is never called with 
size=0, because the call is either from the double underscore function, 
that defaults to DEV_SIZE_MB or from the tst_device binary, that only 
calls tst_acquire_loop_device if the 3 argument version (tst_device 
acquire [size [filename]]) is used and size is not allowed to be 0 in 
that case.