From 0fc71e3d6520ba7abad5cfbc9a33db0190e4d5b8 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Mon, 13 Oct 2008 13:27:59 +0200 Subject: [PATCH] block: add partition attribute for partition number With extended devt, finding out the partition number becomes a bit more challenging as subtracting the minor number from that of the parent device doesn't work anymore. The only thing left is parsing the partition name which is brittle and not exactly universal (some have '-' between the device name and partition number while others don't). This patch introduced partition attribute which contains the partition number of the device. This should make finding partitions and its index easier. This problem and solution were suggested by H. Peter Anvin. Signed-off-by: Tejun Heo Cc: H. Peter Anvin Signed-off-by: Jens Axboe --- fs/partitions/check.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/fs/partitions/check.c b/fs/partitions/check.c index fbeb2f372a9..cfb0c80690a 100644 --- a/fs/partitions/check.c +++ b/fs/partitions/check.c @@ -195,6 +195,14 @@ check_partition(struct gendisk *hd, struct block_device *bdev) return ERR_PTR(res); } +static ssize_t part_partition_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct hd_struct *p = dev_to_part(dev); + + return sprintf(buf, "%d\n", p->partno); +} + static ssize_t part_start_show(struct device *dev, struct device_attribute *attr, char *buf) { @@ -260,6 +268,7 @@ ssize_t part_fail_store(struct device *dev, } #endif +static DEVICE_ATTR(partition, S_IRUGO, part_partition_show, NULL); static DEVICE_ATTR(start, S_IRUGO, part_start_show, NULL); static DEVICE_ATTR(size, S_IRUGO, part_size_show, NULL); static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL); @@ -269,6 +278,7 @@ static struct device_attribute dev_attr_fail = #endif static struct attribute *part_attrs[] = { + &dev_attr_partition.attr, &dev_attr_start.attr, &dev_attr_size.attr, &dev_attr_stat.attr, -- 2.41.1