[PATCH] RDMA/siw: Fix handling of zero-sized Read and Receive Queues.

[Leon Romanovsky]

On Tue, Dec 15, 2020 at 01:23:06PM +0100, Bernard Metzler wrote:
> During connection setup, the application may choose to zero-size
> inbound and outbound READ queues, as well as the Receive queue.
> This patch fixes handling of zero-sized queues.
>
> Reported-by: Kamal Heib <kamalheib1 at gmail.com>
> Reported-by: Yi Zhang <yi.zhang at redhat.com>
> Signed-off-by: Bernard Metzler <bmt at zurich.ibm.com>
> ---
>  drivers/infiniband/sw/siw/siw.h       |  2 +-
>  drivers/infiniband/sw/siw/siw_qp.c    | 54 ++++++++++++++++-----------
>  drivers/infiniband/sw/siw/siw_qp_rx.c | 26 +++++++++----
>  drivers/infiniband/sw/siw/siw_qp_tx.c |  4 +-
>  drivers/infiniband/sw/siw/siw_verbs.c | 18 +++++++--
>  5 files changed, 68 insertions(+), 36 deletions(-)
>
> diff --git a/drivers/infiniband/sw/siw/siw.h b/drivers/infiniband/sw/siw/siw.h
> index e9753831ac3f..6f17392f975a 100644
> --- a/drivers/infiniband/sw/siw/siw.h
> +++ b/drivers/infiniband/sw/siw/siw.h
> @@ -654,7 +654,7 @@ static inline struct siw_sqe *orq_get_free(struct siw_qp *qp)
>  {
>  	struct siw_sqe *orq_e = orq_get_tail(qp);
>
> -	if (orq_e && READ_ONCE(orq_e->flags) == 0)
> +	if (READ_ONCE(orq_e->flags) == 0)
>  		return orq_e;
>
>  	return NULL;
> diff --git a/drivers/infiniband/sw/siw/siw_qp.c b/drivers/infiniband/sw/siw/siw_qp.c
> index 875d36d4b1c6..b686a09a75ae 100644
> --- a/drivers/infiniband/sw/siw/siw_qp.c
> +++ b/drivers/infiniband/sw/siw/siw_qp.c
> @@ -199,26 +199,28 @@ void siw_qp_llp_write_space(struct sock *sk)
>
>  static int siw_qp_readq_init(struct siw_qp *qp, int irq_size, int orq_size)
>  {
> -	irq_size = roundup_pow_of_two(irq_size);
> -	orq_size = roundup_pow_of_two(orq_size);
> -
> -	qp->attrs.irq_size = irq_size;
> -	qp->attrs.orq_size = orq_size;
> -
> -	qp->irq = vzalloc(irq_size * sizeof(struct siw_sqe));
> -	if (!qp->irq) {
> -		siw_dbg_qp(qp, "irq malloc for %d failed\n", irq_size);
> -		qp->attrs.irq_size = 0;
> -		return -ENOMEM;
> +	if (irq_size) {
> +		irq_size = roundup_pow_of_two(irq_size);
> +		qp->irq = vzalloc(irq_size * sizeof(struct siw_sqe));
> +		if (!qp->irq) {
> +			siw_dbg_qp(qp, "irq malloc for %d failed\n", irq_size);

Please don't copy prints after kernel allocators. You won't miss failure
in allocations.

Thanks