Re: [PATCH rdma-next v2 2/2] RDMA/core: Update write interface to use automatic object lifetime

[Jason Gunthorpe <jgg@nvidia.com>]

On Sun, Jul 19, 2020 at 08:22:23AM +0300, Leon Romanovsky wrote:
> From: Leon Romanovsky <leonro@mellanox.com>
> 
> The automatic object lifetime model allows us to change write() interface
> to have same logic as ioctl() path. Update the create/alloc functions to be
> in the following format, so code flow will be the same:
>  * Allocate objects
>  * Initialize them
>  * Call to the drivers, this is last step that is allowed to fail
>  * Finalize object
>  * Return response and allow to core code to handle abort/commit
>    respectively.
> 
> Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
> ---
>  drivers/infiniband/core/uverbs_cmd.c | 312 ++++++++-------------------
>  1 file changed, 93 insertions(+), 219 deletions(-)
> 
> diff --git a/drivers/infiniband/core/uverbs_cmd.c b/drivers/infiniband/core/uverbs_cmd.c
> index 68c9a0210220..a66fc3e37a74 100644
> --- a/drivers/infiniband/core/uverbs_cmd.c
> +++ b/drivers/infiniband/core/uverbs_cmd.c
> @@ -273,7 +273,7 @@ int ib_init_ucontext(struct uverbs_attr_bundle *attrs)
>  
>  static int ib_uverbs_get_context(struct uverbs_attr_bundle *attrs)
>  {
> -	struct ib_uverbs_get_context_resp resp;
> +	struct ib_uverbs_get_context_resp resp = {};
>  	struct ib_uverbs_get_context cmd;
>  	struct ib_device *ib_dev;
>  	struct ib_uobject *uobj;
> @@ -293,25 +293,20 @@ static int ib_uverbs_get_context(struct uverbs_attr_bundle *attrs)
>  		goto err_ucontext;
>  	}
>  
> -	resp = (struct ib_uverbs_get_context_resp){
> -		.num_comp_vectors = attrs->ufile->device->num_comp_vectors,
> -		.async_fd = uobj->id,
> -	};
> -	ret = uverbs_response(attrs, &resp, sizeof(resp));
> -	if (ret)
> -		goto err_uobj;
> -
>  	ret = ib_init_ucontext(attrs);
>  	if (ret)
>  		goto err_uobj;

init_ucontext cannot be undone and cannot be called twice, so it must
be last in the function. I dropped the hunk changing ib_uverbs_get_context().

Applied to for-next, thanks

Jason