Re: [PATCH V2] misc large filesystem fixes

[Eryu Guan <guaneryu@gmail.com>]

On Tue, Sep 25, 2018 at 02:12:40PM -0500, Eric Sandeen wrote:
> There are a few tests which fail on large filesytems because
> we run into mkfs limits.
> 
> xfs/010, xfs/013, and xfs/062 specify AG count, but if the device
> is larger than agcount*1T this will fail.  Add a mkfs helper that
> will adjust the data size to accommodate the ag count request.
> xfs/178 tries to decrease the agcount and re-mkfs, but if the
> default AG size was chosen to be 1T, decreasing the AG count
> results in too-large AGs and mkfs fails.  The intention here
> AFAICT is to simply re-mkfs with non-overlapping AG headers,
> so increasing the AG count should achieve the same purpose,
> and cause mkfs to choose a smaller-than-default AG size which
> should pass.
> 
> Signed-off-by: Eric Sandeen <sandeen@redhat.com>
> ---
> 
> diff --git a/common/xfs b/common/xfs
> index d971b4a8..34412882 100644
> --- a/common/xfs
> +++ b/common/xfs
> @@ -110,6 +110,21 @@ _scratch_mkfs_xfs()
>  	return $mkfs_status
>  }
>  
> +_scratch_mkfs_xfs_agcount()
> +{
> +	local agcount=$1
> +	local opts=$2
> +
> +	# If $agcount AGs would result in too-large AG size, restrict the size
> +	# to create $agcount AGS roughly 1T in size.
> +	local dsizeopt=""
> +	dev_sz=$(blockdev --getsize64 $SCRATCH_DEV)

local dev_sz ?

> +	if [ "$dev_sz" -ge "$(($agcount*(2**40)))" ]; then
> +		  dsizeopt="-d size=$(($agcount*((2**40)-1)))"

Hmm.. this size doesn't seem right to me, I think the $agcount should
not be accounted in the size, otherwise the size can go beyond 1T again.

(After fixing above issue) mkfs reports failure as well:

"illegal data length 2199023255550, not a multiple of 512"

Perhaps $((((2**40)) - 4096)) would be a safe size.

Thanks,
Eryu

> +	fi
> +	_scratch_mkfs_xfs "$opts -d agcount=$agcount $dsizeopt" | _filter_mkfs 2>$seqres.full
> +}
> +
>  # xfs_check script is planned to be deprecated. But, we want to
>  # be able to invoke "xfs_check" behavior in xfstests in order to
>  # maintain the current verification levels.
> diff --git a/tests/xfs/010 b/tests/xfs/010
> index ee1595c8..5da815a5 100755
> --- a/tests/xfs/010
> +++ b/tests/xfs/010
> @@ -96,7 +96,7 @@ _require_xfs_finobt
>  
>  rm -f $seqres.full
>  
> -_scratch_mkfs_xfs "-m crc=1,finobt=1 -d agcount=2" | _filter_mkfs 2>$seqres.full
> +_scratch_mkfs_xfs_agcount 2 "-m crc=1,finobt=1"
>  
>  # sparsely populate the fs such that we create records with free inodes
>  _scratch_mount
> diff --git a/tests/xfs/013 b/tests/xfs/013
> index 4d31d793..f45217ba 100755
> --- a/tests/xfs/013
> +++ b/tests/xfs/013
> @@ -97,8 +97,7 @@ _require_command "$KILLALL_PROG" killall
>  
>  rm -f $seqres.full
>  
> -_scratch_mkfs_xfs "-m crc=1,finobt=1 -d agcount=2" | \
> -	_filter_mkfs 2>> $seqres.full
> +_scratch_mkfs_xfs_agcount 2 "-m crc=1,finobt=1"
>  _scratch_mount
>  
>  COUNT=20000	# number of files per directory
> diff --git a/tests/xfs/062 b/tests/xfs/062
> index 755c5243..c0f82a78 100755
> --- a/tests/xfs/062
> +++ b/tests/xfs/062
> @@ -57,7 +57,7 @@ rm -f $seqres.full
>  DIRCOUNT=8
>  INOCOUNT=$((2048 / DIRCOUNT))
>  
> -_scratch_mkfs "-d agcount=$DIRCOUNT" >> $seqres.full 2>&1 || _fail "mkfs failed"
> +_scratch_mkfs_xfs_agcount $DIRCOUNT >> $seqres.full 2>&1 || _fail "mkfs failed"
>  _scratch_mount
>  
>  # create a set of directories and fill each with a fixed number of files
> diff --git a/tests/xfs/178 b/tests/xfs/178
> index 84151056..f7ea9139 100755
> --- a/tests/xfs/178
> +++ b/tests/xfs/178
> @@ -51,8 +51,8 @@ _supported_os Linux
>  # o Summary of testing:
>  #    1. mkfs.xfs a default filesystem, note agcount value.
>  #    2. dd zero first sector and repair and verify.
> -#    3. mkfs.xfs overriding agcount to a smaller value
> -#             (ie. each AG is bigger)
> +#    3. mkfs.xfs overriding agcount to a larger value
> +#             (ie. each AG is smaller)
>  #    4. dd zero first sector, repair and verify.
>  #          -> old mkfs.xfs will cause repair to incorrectly
>  #             fix filesystem, new mkfs.xfs will be fine.
> @@ -74,8 +74,8 @@ fi
>  
>  _dd_repair_check $SCRATCH_DEV $sectsz
>  
> -# smaller AGCOUNT
> -let "agcount=$agcount-2"
> +# larger AGCOUNT
> +let "agcount=$agcount+2"
>  _scratch_mkfs_xfs -dagcount=$agcount >/dev/null 2>&1 \
>          || _fail "mkfs failed!"
>  
>