[LTP] [PATCH] mkswap: make the test device size is aligned to pagesize

[Cyril Hrubis <chrubis@suse.cz>]

Hi!
> My version is:
> 
> # rpm -qf /sbin/mkswap 
> util-linux-2.23.2-33.el7.ppc64
> 
> 
> if (block_count) {
> 	/* this silly user specified the number of blocks explicitly */
> 		uint64_t blks = strtou64_or_err(block_count,
> 					_("invalid block count argument"));
> 		PAGES = blks / (pagesize / 1024);
> 	}
> 	sz = get_size(device_name);

There is no check here as well. The strtou64_or_err() just converts
string to number, that's all it does. Then we do integer division, no
checks at all.

> > Looking into util-linux-2.26.2 all it does with user specified number of
> > blocks is:
> > 
> > ctl.npages = blks / (ctl.pagesize / 1024);
> > 
> > There is no check that blks is divideable by pagesize/1024.
> 
> I build util-linux-2.28 from upstrem source and also get the errors.
> 
> # mkswap -V
> mkswap from util-linux 2.28.237-47bd89
> 
> # ./runltp -f commands
> mkswap01 1 TINFO : Using test device LTP_DEV='/dev/loop0'
> mkswap01 1 TFAIL : 'mkswap   /dev/loop0 ' failed, not expected.
> mkswap01 2 TFAIL : 'mkswap   /dev/loop0 90000' failed, not expected.
> mkswap01 3 TINFO : Can not do swapon on /dev/loop0.
> mkswap01 3 TINFO : Device size specified by 'mkswap' greater than real size.
> mkswap01 3 TINFO : Swapon failed expectedly.
> mkswap01 3 TPASS : 'mkswap -f  /dev/loop0 110000' passed.

Hmm, what is the exact error message from mkfs here?

I guess that it would be a good idea to cat the temp file if mkswap
failed unexpectedly so that we can see the mkswap error message.

> Additionally, we'd better change the bs=1kB to bs=1024 in runltp file,
> since it will get page aligned block device for all arches.
> 
> The original LTP_DEV size is 102400000 bytes:
> 
> # grep 'bs=' runltp  -n
> 981:    dd if=/dev/zero of=${TMP}/test.img bs=1kB count=102400
> 
> 
> From dd manual:
> N and BYTES may be followed by the following multiplicative suffixes:
> c =1, w =2, b =512, kB  =1000,  K  =1024,  MB =1000*1000,  M  =1024*1024,
> xM  =M  GB  =1000*1000*1000,  G =1024*1024*1024, and so on for T, P, E, Z, Y.

Or change it to uppercase KB. Sounds good, feel free to send a patch.

-- 
Cyril Hrubis
chrubis@suse.cz