diff options
| author | Matteo Croce <[email protected]> | 2021-07-13 01:05:28 +0200 |
|---|---|---|
| committer | Jens Axboe <[email protected]> | 2021-08-02 13:37:28 -0600 |
| commit | 13927b31b13f3c6556221eff3487247bd3c7a245 (patch) | |
| tree | 41e7a6dd8a1acd054f7edfea42b451c2a279568e | |
| parent | 7957d93bf32bc211415827e44fdd9cdf1388df59 (diff) | |
block: export diskseq in sysfs
Add a new sysfs handle to export the new diskseq value.
Place it in <sysfs>/block/<disk>/diskseq and document it.
$ grep . /sys/class/block/*/diskseq
/sys/class/block/loop0/diskseq:13
/sys/class/block/loop1/diskseq:14
/sys/class/block/loop2/diskseq:5
/sys/class/block/loop3/diskseq:6
/sys/class/block/ram0/diskseq:1
/sys/class/block/ram1/diskseq:2
/sys/class/block/vda/diskseq:7
Reviewed-by: Christoph Hellwig <[email protected]>
Signed-off-by: Matteo Croce <[email protected]>
Tested-by: Luca Boccassi <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>
| -rw-r--r-- | Documentation/ABI/testing/sysfs-block | 12 | ||||
| -rw-r--r-- | block/genhd.c | 10 |
2 files changed, 22 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-block b/Documentation/ABI/testing/sysfs-block index e34cdeeeb9d4..a0ed87386639 100644 --- a/Documentation/ABI/testing/sysfs-block +++ b/Documentation/ABI/testing/sysfs-block @@ -28,6 +28,18 @@ Description: For more details refer Documentation/admin-guide/iostats.rst +What: /sys/block/<disk>/diskseq +Date: February 2021 +Contact: Matteo Croce <[email protected]> +Description: + The /sys/block/<disk>/diskseq files reports the disk + sequence number, which is a monotonically increasing + number assigned to every drive. + Some devices, like the loop device, refresh such number + every time the backing file is changed. + The value type is 64 bit unsigned. + + What: /sys/block/<disk>/<part>/stat Date: February 2008 Contact: Jerome Marchand <[email protected]> diff --git a/block/genhd.c b/block/genhd.c index e1b2f898d790..a4817e42f3a3 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -977,6 +977,14 @@ static ssize_t disk_discard_alignment_show(struct device *dev, return sprintf(buf, "%d\n", queue_discard_alignment(disk->queue)); } +static ssize_t diskseq_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct gendisk *disk = dev_to_disk(dev); + + return sprintf(buf, "%llu\n", disk->diskseq); +} + static DEVICE_ATTR(range, 0444, disk_range_show, NULL); static DEVICE_ATTR(ext_range, 0444, disk_ext_range_show, NULL); static DEVICE_ATTR(removable, 0444, disk_removable_show, NULL); @@ -989,6 +997,7 @@ static DEVICE_ATTR(capability, 0444, disk_capability_show, NULL); static DEVICE_ATTR(stat, 0444, part_stat_show, NULL); static DEVICE_ATTR(inflight, 0444, part_inflight_show, NULL); static DEVICE_ATTR(badblocks, 0644, disk_badblocks_show, disk_badblocks_store); +static DEVICE_ATTR(diskseq, 0444, diskseq_show, NULL); #ifdef CONFIG_FAIL_MAKE_REQUEST ssize_t part_fail_show(struct device *dev, @@ -1034,6 +1043,7 @@ static struct attribute *disk_attrs[] = { &dev_attr_events.attr, &dev_attr_events_async.attr, &dev_attr_events_poll_msecs.attr, + &dev_attr_diskseq.attr, #ifdef CONFIG_FAIL_MAKE_REQUEST &dev_attr_fail.attr, #endif |