From 86b37281411cf1e9bc0a6b5406c45edb7bd9ea5d Mon Sep 17 00:00:00 2001 From: "Martin K. Petersen" Date: Tue, 10 Nov 2009 11:50:21 +0100 Subject: block: Expose discard granularity While SSDs track block usage on a per-sector basis, RAID arrays often have allocation blocks that are bigger. Allow the discard granularity and alignment to be set and teach the topology stacking logic how to handle them. Signed-off-by: Martin K. Petersen Signed-off-by: Jens Axboe --- block/genhd.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'block/genhd.c') diff --git a/block/genhd.c b/block/genhd.c index 517e4332cb37..b11a4ad7d571 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -861,12 +861,23 @@ static ssize_t disk_alignment_offset_show(struct device *dev, return sprintf(buf, "%d\n", queue_alignment_offset(disk->queue)); } +static ssize_t disk_discard_alignment_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct gendisk *disk = dev_to_disk(dev); + + return sprintf(buf, "%u\n", queue_discard_alignment(disk->queue)); +} + static DEVICE_ATTR(range, S_IRUGO, disk_range_show, NULL); static DEVICE_ATTR(ext_range, S_IRUGO, disk_ext_range_show, NULL); static DEVICE_ATTR(removable, S_IRUGO, disk_removable_show, NULL); static DEVICE_ATTR(ro, S_IRUGO, disk_ro_show, NULL); static DEVICE_ATTR(size, S_IRUGO, part_size_show, NULL); static DEVICE_ATTR(alignment_offset, S_IRUGO, disk_alignment_offset_show, NULL); +static DEVICE_ATTR(discard_alignment, S_IRUGO, disk_discard_alignment_show, + NULL); static DEVICE_ATTR(capability, S_IRUGO, disk_capability_show, NULL); static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL); static DEVICE_ATTR(inflight, S_IRUGO, part_inflight_show, NULL); @@ -887,6 +898,7 @@ static struct attribute *disk_attrs[] = { &dev_attr_ro.attr, &dev_attr_size.attr, &dev_attr_alignment_offset.attr, + &dev_attr_discard_alignment.attr, &dev_attr_capability.attr, &dev_attr_stat.attr, &dev_attr_inflight.attr, -- cgit v1.2.3