On 5/22/19 11:44 AM, Darrick J. Wong wrote:
> On Tue, May 21, 2019 at 02:30:57PM -0500, Eric Sandeen wrote:
>> From: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
>>
>> Data block sharing (a.k.a. reflink) has been stable for a while, so turn
>> it on by default.
>>
>> Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
>> [sandeen: update comments & man page]
>> Signed-off-by: Eric Sandeen <sandeen@xxxxxxxxxx>
>
> Looks good to me.
> Reviewed-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
>
> Hmm I'm not allowed to RVB my own patch, right?
Nor I my part? ;) I'll maintain your authorship, add my
[sandeen: stuff]
part, and add my RVB.
-Eric
>
> --D
>
>> ---
>>
>> diff --git a/man/man8/mkfs.xfs.8 b/man/man8/mkfs.xfs.8
>> index 4b8c78c..78b1501 100644
>> --- a/man/man8/mkfs.xfs.8
>> +++ b/man/man8/mkfs.xfs.8
>> @@ -231,7 +231,7 @@ available for the data forks of regular files.
>> .IP
>> By default,
>> .B mkfs.xfs
>> -will not create reference count btrees and therefore will not enable the
>> +will create reference count btrees and therefore will enable the
>> reflink feature. This feature is only available for filesystems created with
>> the (default)
>> .B \-m crc=1
>> @@ -239,6 +239,13 @@ option set. When the option
>> .B \-m crc=0
>> is used, the reference count btree feature is not supported and reflink is
>> disabled.
>> +.IP
>> +Note: the filesystem DAX mount option (
>> +.B \-o dax
>> +) is incompatible with
>> +reflink-enabled XFS filesystems. To use filesystem DAX with XFS, specify the
>> +.B \-m reflink=0
>> +option to mkfs.xfs to disable the reflink feature.
>> .RE
>> .TP
>> .BI \-d " data_section_options"
>> diff --git a/mkfs/xfs_mkfs.c b/mkfs/xfs_mkfs.c
>> index 0910664..ddb25ec 100644
>> --- a/mkfs/xfs_mkfs.c
>> +++ b/mkfs/xfs_mkfs.c
>> @@ -1973,15 +1973,15 @@ _("Directory ftype field always enabled on CRC enabled filesystems\n"));
>> usage();
>> }
>>
>> - } else {
>> + } else { /* !crcs_enabled */
>> /*
>> - * The kernel doesn't currently support crc=0,finobt=1
>> - * filesystems. If crcs are not enabled and the user has not
>> - * explicitly turned finobt on, then silently turn it off to
>> - * avoid an unnecessary warning.
>> + * The kernel doesn't support crc=0,finobt=1 filesystems.
>> + * If crcs are not enabled and the user has not explicitly
>> + * turned finobt on, then silently turn it off to avoid an
>> + * unnecessary warning.
>> * If the user explicitly tried to use crc=0,finobt=1,
>> * then issue an error.
>> - * The same is also for sparse inodes.
>> + * The same is also true for sparse inodes and reflink.
>> */
>> if (cli->sb_feat.finobt && cli_opt_set(&mopts, M_FINOBT)) {
>> fprintf(stderr,
>> @@ -2004,7 +2004,7 @@ _("rmapbt not supported without CRC support\n"));
>> }
>> cli->sb_feat.rmapbt = false;
>>
>> - if (cli->sb_feat.reflink) {
>> + if (cli->sb_feat.reflink && cli_opt_set(&mopts, M_REFLINK)) {
>> fprintf(stderr,
>> _("reflink not supported without CRC support\n"));
>> usage();
>> @@ -3876,7 +3876,7 @@ main(
>> .finobt = true,
>> .spinodes = true,
>> .rmapbt = false,
>> - .reflink = false,
>> + .reflink = true,
>> .parent_pointers = false,
>> .nodalign = false,
>> .nortalign = false,
>>
>>
>
