[PATCH] null_blk: Add notes to use LightNVM

[PATCH] null_blk: Add notes to use LightNVM

[Yasuaki Ishimatsu]

If CONFIG_NVM is disabled, loading null_block module with use_lightnvm=1
fails. But there are no messages and documents related to the failure.

So the patch adds the notes to use LightNVM.

Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Jens Axboe <axboe@kernel.dk>
---
  Documentation/block/null_blk.txt | 2 +-
  drivers/block/null_blk.c         | 1 +
  2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/Documentation/block/null_blk.txt b/Documentation/block/null_blk.txt
index d8880ca..0365a26 100644
--- a/Documentation/block/null_blk.txt
+++ b/Documentation/block/null_blk.txt
@@ -72,4 +72,4 @@ use_per_node_hctx=[0/1]: Default: 0
       queue for each CPU node in the system.

  use_lightnvm=[0/1]: Default: 0
-  Register device with LightNVM. Requires blk-mq to be used.
+  Register device with LightNVM. Requires blk-mq and CONFIG_NVM=y to be used.
diff --git a/drivers/block/null_blk.c b/drivers/block/null_blk.c
index ba6f4a2e..4943ee2 100644
--- a/drivers/block/null_blk.c
+++ b/drivers/block/null_blk.c
@@ -577,6 +577,7 @@ static void null_nvm_unregister(struct nullb *nullb)
  #else
  static int null_nvm_register(struct nullb *nullb)
  {
+	pr_err("null_blk: CONFIG_NVM needs to be enabled for LightNVM\n");
  	return -EINVAL;
  }
  static void null_nvm_unregister(struct nullb *nullb) {}
-- 
1.8.3.1

Re: [PATCH] null_blk: Add notes to use LightNVM

[Yasuaki Ishimatsu]

Could you review the patch?

On 10/27/2016 11:56 AM, Yasuaki Ishimatsu wrote:
> If CONFIG_NVM is disabled, loading null_block module with use_lightnvm=1
> fails. But there are no messages and documents related to the failure.
>
> So the patch adds the notes to use LightNVM.
>
> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
> Cc: Jens Axboe <axboe@kernel.dk>
> ---
>  Documentation/block/null_blk.txt | 2 +-
>  drivers/block/null_blk.c         | 1 +
>  2 files changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/Documentation/block/null_blk.txt b/Documentation/block/null_blk.txt
> index d8880ca..0365a26 100644
> --- a/Documentation/block/null_blk.txt
> +++ b/Documentation/block/null_blk.txt
> @@ -72,4 +72,4 @@ use_per_node_hctx=[0/1]: Default: 0
>       queue for each CPU node in the system.
>
>  use_lightnvm=[0/1]: Default: 0
> -  Register device with LightNVM. Requires blk-mq to be used.
> +  Register device with LightNVM. Requires blk-mq and CONFIG_NVM=y to be used.
> diff --git a/drivers/block/null_blk.c b/drivers/block/null_blk.c
> index ba6f4a2e..4943ee2 100644
> --- a/drivers/block/null_blk.c
> +++ b/drivers/block/null_blk.c
> @@ -577,6 +577,7 @@ static void null_nvm_unregister(struct nullb *nullb)
>  #else
>  static int null_nvm_register(struct nullb *nullb)
>  {
> +    pr_err("null_blk: CONFIG_NVM needs to be enabled for LightNVM\n");
>      return -EINVAL;
>  }
>  static void null_nvm_unregister(struct nullb *nullb) {}

Re: [PATCH] null_blk: Add notes to use LightNVM

[Jens Axboe]

On 10/27/2016 09:56 AM, Yasuaki Ishimatsu wrote:
> If CONFIG_NVM is disabled, loading null_block module with use_lightnvm=1
> fails. But there are no messages and documents related to the failure.
>
> So the patch adds the notes to use LightNVM.

Added, with some slight text adjustments. Thanks.

-- 
Jens Axboe