Re: [PATCH] loop: set physical block size to logical block size

[Chandan Rajendra <chandan@linux.vnet.ibm.com>]

On Wednesday, September 6, 2017 2:54:47 AM IST Omar Sandoval wrote:
> From: Omar Sandoval <osandov@fb.com>
> 
> Commit 6c6b6f28b333 ("loop: set physical block size to PAGE_SIZE")
> caused mkfs.xfs to barf on ppc64 [1]. Always using PAGE_SIZE as the
> physical block size still makes the most sense semantically, but let's
> just lie and always set it to the same value as the logical block size
> (same goes for io_min). In the future we might want to at least bump up
> io_min to PAGE_SIZE but I'm sick of these stupid changes so let's play
> it safe.
> 

With this patch applied, On ppc64 I get,

# blockdev --getss /dev/loop0    
512                                                           
# blockdev --getpbsz /dev/loop0  
512                                                           

i.e. we are back to what was being reported before commit 6c6b6f28b333 
was applied.

I also executed xfstests on xfs filesystems with 4k and 32k block sizes and 
did not notice any regressions.

Tested-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>

-- 
chandan