On 09/29/2016 02:39 AM, Darrick J. Wong wrote: > After much discussion, it seems that the fallocate feature flag > FALLOC_FL_ZERO_RANGE maps nicely to SCSI WRITE SAME; and the feature > FALLOC_FL_PUNCH_HOLE maps nicely to the devices that have been > whitelisted for zeroing SCSI UNMAP. Punch still requires that > FALLOC_FL_KEEP_SIZE is set. A length that goes past the end of the > device will be clamped to the device size if KEEP_SIZE is set; or will > return -EINVAL if not. Both start and length must be aligned to the > device's logical block size. > > Since the semantics of fallocate are fairly well established already, > wire up the two pieces. The other fallocate variants (collapse range, > insert range, and allocate blocks) are not supported. > > Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx> > --- > v2: Incorporate feedback from Christoph & Linus. Tentatively add > a requirement that the fallocate arguments be aligned to logical block > size, and put in a few XXX comments ahead of LSF discussion. > v3: Forward port to 4.7. > v4: Forward port to 4.8. > --- > fs/block_dev.c | 78 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ > fs/open.c | 3 +- > 2 files changed, 80 insertions(+), 1 deletion(-) > Reviewed-by: Hannes Reinecke <hare@xxxxxxxx> Cheers, Hannes -- Dr. Hannes Reinecke zSeries & Storage hare@xxxxxxx +49 911 74053 688 SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: J. Hawn, J. Guild, F. Imendörffer, HRB 16746 (AG Nürnberg) _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs