Re: [PATCH] block:Change the function,nvme_alloc_queue to use -ENOMEM for when failing memory allocations

Re: [PATCH] block:Change the function,nvme_alloc_queue to use -ENOMEM for when failing memory allocations

[Matthew Wilcox]

On Tue, May 12, 2015 at 07:51:31PM -0400, Nicholas Krause wrote:
> This changes the function,nvme_alloc_queue to use the kernel code,
> -ENOMEM for when failing to allocate the memory required for the
> nvme_queue structure pointer,nvme in order to correctly return
> to the caller the correct reason for this function's failing.

>  	if (!nvmeq)
> -		return NULL;
> +		return -ENOMEM;
>  

You didn't even compile-test this, did you?

Re: [PATCH] block:Change the function, nvme_alloc_queue to use -ENOMEM for when failing memory allocations

[Keith Busch]

On Tue, 12 May 2015, Nicholas Krause wrote:
> This changes the function,nvme_alloc_queue to use the kernel code,
> -ENOMEM for when failing to allocate the memory required for the
> nvme_queue structure pointer,nvme in order to correctly return
> to the caller the correct reason for this function's failing.

Nak! Look at what the callers are checking for upon return.

> Signed-off-by: Nicholas Krause <xerofoify@gmail.com>
> ---
> drivers/block/nvme-core.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/block/nvme-core.c b/drivers/block/nvme-core.c
> index 85b8036..e2eac1e 100644
> --- a/drivers/block/nvme-core.c
> +++ b/drivers/block/nvme-core.c
> @@ -1387,7 +1387,7 @@ static struct nvme_queue *nvme_alloc_queue(struct nvme_dev *dev, int qid,
> 	struct device *dmadev = &dev->pci_dev->dev;
> 	struct nvme_queue *nvmeq = kzalloc(sizeof(*nvmeq), GFP_KERNEL);
> 	if (!nvmeq)
> -		return NULL;
> +		return -ENOMEM;
>
> 	nvmeq->cqes = dma_zalloc_coherent(dmadev, CQ_SIZE(depth),
> 					  &nvmeq->cq_dma_addr, GFP_KERNEL);