[PATCH] nvdimm/of_pmem: Provide a unique name for bus provider

[Aneesh Kumar K.V]

On 8/7/19 9:43 AM, Dan Williams wrote:
> On Tue, Aug 6, 2019 at 9:00 PM Aneesh Kumar K.V
> <aneesh.kumar at linux.ibm.com> wrote:
>>
>> ndctl utility requires the ndbus to have unique names. If not while
>> enumerating the bus in userspace it drops bus with similar names.
>> This results in us not listing devices beneath the bus.
> 
> It does?
> 
>>
>> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar at linux.ibm.com>
>> ---
>>   drivers/nvdimm/of_pmem.c | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/nvdimm/of_pmem.c b/drivers/nvdimm/of_pmem.c
>> index a0c8dcfa0bf9..97187d6c0bdb 100644
>> --- a/drivers/nvdimm/of_pmem.c
>> +++ b/drivers/nvdimm/of_pmem.c
>> @@ -42,7 +42,7 @@ static int of_pmem_region_probe(struct platform_device *pdev)
>>                  return -ENOMEM;
>>
>>          priv->bus_desc.attr_groups = bus_attr_groups;
>> -       priv->bus_desc.provider_name = "of_pmem";
>> +       priv->bus_desc.provider_name = kstrdup(pdev->name, GFP_KERNEL);
> 
> This looks ok to me to address support for older ndctl binaries, but
> I'd like to also fix the ndctl bug that makes non-unique provider
> names fail.
> 

0462269ab121d323a016874ebdd42217f2911ee7 (ndctl: provide a method to 
invalidate the bus list)

This hunk does the filtering.

@@ -928,6 +929,14 @@ static int add_bus(void *parent, int id, const char 
*ctl_base)
  		goto err_read;
  	bus->buf_len = strlen(bus->bus_path) + 50;

+	ndctl_bus_foreach(ctx, bus_dup)
+		if (strcmp(ndctl_bus_get_provider(bus_dup),
+					ndctl_bus_get_provider(bus)) == 0) {
+			free_bus(bus, NULL);
+			free(path);
+			return 1;
+		}
+
  	list_add(&ctx->busses, &bus->list);

  	rc = 0;