7:24 a.m.
On Tue, 2016-07-26 at 14:58 -0600, Vishal Verma wrote:
On 07/26, Linda Knippers wrote:
>
> My system has 4 8G NVDIMMs and I have them configured in different
> ways, as you can
> see from the ndctl output:
>
> $ ndctl list
> [
> {
> "dev":"namespace3.0",
> "mode":"raw",
> "size":8589934592,
> "blockdev":"pmem3"
> },
> {
> "dev":"namespace2.0",
> "mode":"memory",
> "size":8587837440,
> "uuid":"2567d762-68ae-486b-a6eb-2d3ab1b9dca9",
> "blockdev":"pmem2"
> },
> {
> "dev":"namespace1.0",
> "mode":"sector",
> "uuid":"44fb474e-7db8-4438-ad95-05ecb9f2075e",
> "sector_size":4096,
> "blockdev":"pmem1s"
> },
> {
> "dev":"namespace0.0",
> "mode":"memory",
> "size":8453619712,
> "uuid":"933ed54b-5b64-47f1-8409-c88f7c846522",
> "blockdev":"pmem0"
> }
> ]
>
> The two memory namespaces have different sizes because one is --
> map=dev and the other is --map=mem.
> It would be nice if the map option was displayed but my question is
> about the size value for the
> btt device, or lack of one.
>
> All the namespaces show a size except for the btt. The btt only
> shows a sector size. There
> is no size value exposed by the btt sysfs information, which is
> probably why it's not in ndctl.
>
> I know the size can be gotten from the block device but it looks
> like an omission here.
> Is this a bug or a feature?
Probably an omission :)
This patch should expose a size attribute in sysfs:
$ cat /sys/bus/nd/devices/btt7.0/size
32440320
I can look at the 'ndctl list' enabling too if this looks good.
8<------
From fb119bf4380d1d65d82754e581bbd41161c2100f Mon Sep 17 00:00:00 2001
From: Vishal Verma <vishal.l.verma(a)intel.com>
Date: Tue, 26 Jul 2016 14:54:39 -0600
Subject: [PATCH] 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>
Reported-by: Linda Knippers <linda.knippers(a)hpe.com>
Signed-off-by: Vishal Verma <vishal.l.verma(a)intel.com>
---
drivers/nvdimm/btt.c | 1 +
drivers/nvdimm/btt_devs.c | 15 +++++++++++++++
drivers/nvdimm/nd.h | 1 +
3 files changed, 17 insertions(+)
diff --git a/drivers/nvdimm/btt.c b/drivers/nvdimm/btt.c
index 68a7c3c..71ce0dc 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 * btt->sector_size;
Blargh, I think I was a bit hasty; I think this should be:
+ btt->nd_btt->size = btt->nlba * (u64)btt->sector_size;
Right? (I always get bit by integer promotion rules...)
> revalidate_disk(btt->btt_disk);
>
> return 0;
> diff --git a/drivers/nvdimm/btt_devs.c b/drivers/nvdimm/btt_devs.c
> index 3fa7919..b54cfc7 100644
> --- a/drivers/nvdimm/btt_devs.c
> +++ b/drivers/nvdimm/btt_devs.c
> @@ -140,10 +140,25 @@ 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;
> +
> + nvdimm_bus_lock(dev);
> + rc = sprintf(buf, "%llu\n", nd_btt->size);
> + nvdimm_bus_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;
> };