Whether this is set or not is important for whether good performance is possible, when using the block device as a backstore for the kernel target. Exposing this will let kernel target configuration tools provide this information to the user when configuring LIO targets.
Reviewed-by: Chris Leech <[email protected]> Signed-off-by: Andy Grover <[email protected]> --- block/genhd.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/block/genhd.c b/block/genhd.c index 791f419..258fadc 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -958,6 +958,14 @@ static ssize_t disk_capability_show(struct device *dev, return sprintf(buf, "%x\n", disk->flags); } +static ssize_t req_flush_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct gendisk *disk = dev_to_disk(dev); + + return sprintf(buf, "%x\n", !!(disk->queue->flush_flags & REQ_FLUSH)); +} + static ssize_t disk_alignment_offset_show(struct device *dev, struct device_attribute *attr, char *buf) @@ -985,6 +993,7 @@ 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(req_flush, S_IRUGO, req_flush_show, NULL); static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL); static DEVICE_ATTR(inflight, S_IRUGO, part_inflight_show, NULL); #ifdef CONFIG_FAIL_MAKE_REQUEST @@ -1006,6 +1015,7 @@ static struct attribute *disk_attrs[] = { &dev_attr_alignment_offset.attr, &dev_attr_discard_alignment.attr, &dev_attr_capability.attr, + &dev_attr_req_flush.attr, &dev_attr_stat.attr, &dev_attr_inflight.attr, #ifdef CONFIG_FAIL_MAKE_REQUEST -- 1.9.0 -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
