[PATCH v2] nvdimm, btt: add a size attribute for BTTs

To be consistent with other namespaces, expose a 'size' attribute for BTT devices also. Cc: Dan Williams <dan.j.williams(a)intel.com&gt; Reported-by: Linda Knippers <linda.knippers(a)hpe.com&gt; Signed-off-by: Vishal Verma <vishal.l.verma(a)intel.com&gt; --- v2: - Use the correct locking in size_show (Dan) - Use a typecast for 64b multiplication drivers/nvdimm/btt.c | 1 + drivers/nvdimm/btt_devs.c | 20 ++++++++++++++++++++ drivers/nvdimm/nd.h | 1 + 3 files changed, 22 insertions(+) diff --git a/drivers/nvdimm/btt.c b/drivers/nvdimm/btt.c index 68a7c3c..e0084ae 100644 --- a/drivers/nvdimm/btt.c +++ b/drivers/nvdimm/btt.c @@ -1270,6 +1270,7 @@ static int btt_blk_init(struct btt *btt) } } set_capacity(btt->btt_disk, btt->nlba * btt->sector_size >> 9); + btt->nd_btt->size = btt->nlba * (u64)btt->sector_size; revalidate_disk(btt->btt_disk); return 0; diff --git a/drivers/nvdimm/btt_devs.c b/drivers/nvdimm/btt_devs.c index 3fa7919..97dd292 100644 --- a/drivers/nvdimm/btt_devs.c +++ b/drivers/nvdimm/btt_devs.c @@ -140,10 +140,30 @@ static ssize_t namespace_store(struct device *dev, } static DEVICE_ATTR_RW(namespace); +static ssize_t size_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct nd_btt *nd_btt = to_nd_btt(dev); + ssize_t rc; + + device_lock(dev); + if (dev->driver) + rc = sprintf(buf, "%llu\n", nd_btt->size); + else { + /* no size to convey if the btt instance is disabled */ + rc = -ENXIO; + } + device_unlock(dev); + + return rc; +} +static DEVICE_ATTR_RO(size); + static struct attribute *nd_btt_attributes[] = { &dev_attr_sector_size.attr, &dev_attr_namespace.attr, &dev_attr_uuid.attr, + &dev_attr_size.attr, NULL, }; diff --git a/drivers/nvdimm/nd.h b/drivers/nvdimm/nd.h index 4047639..8024a0e 100644 --- a/drivers/nvdimm/nd.h +++ b/drivers/nvdimm/nd.h @@ -143,6 +143,7 @@ struct nd_btt { struct nd_namespace_common *ndns; struct btt *btt; unsigned long lbasize; + u64 size; u8 *uuid; int id; }; -- 2.7.4