RE: [RFC v1 12/19] RDMA/irdma: Implement device supported verb APIs

["Saleem, Shiraz" <shiraz.saleem@intel.com>]

>Subject: Re: [RFC v1 12/19] RDMA/irdma: Implement device supported verb APIs
>
>On 15-Feb-19 19:10, Shiraz Saleem wrote:
>> /**
>>  * irdma_dealloc_ucontext - deallocate the user context data structure
>>  * @context: user context created during alloc  */ static int
>> irdma_dealloc_ucontext(struct ib_ucontext *context) {
>> 	struct irdma_ucontext *ucontext = to_ucontext(context);
>> 	unsigned long flags;
>>
>> 	spin_lock_irqsave(&ucontext->cq_reg_mem_list_lock, flags);
>> 	if (!list_empty(&ucontext->cq_reg_mem_list)) {
>> 		spin_unlock_irqrestore(&ucontext->cq_reg_mem_list_lock, flags);
>> 		return -EBUSY;
>> 	}
>> 	spin_unlock_irqrestore(&ucontext->cq_reg_mem_list_lock, flags);
>>
>> 	spin_lock_irqsave(&ucontext->qp_reg_mem_list_lock, flags);
>> 	if (!list_empty(&ucontext->qp_reg_mem_list)) {
>> 		spin_unlock_irqrestore(&ucontext->qp_reg_mem_list_lock, flags);
>> 		return -EBUSY;
>
>Drivers are not permitted to fail dealloc_ucontext.

This is fixed in RFC v1 submission. Maybe this was pasted from the v0 ver?

[..]

>> +/**
>> + * irdma_alloc_pd - allocate protection domain
>> + * @pd: PD pointer
>> + * @context: user context created during alloc
>> + * @udata: user data
>> + */
>> +static int irdma_alloc_pd(struct ib_pd *pd,
>> +			  struct ib_ucontext *context,
>> +			  struct ib_udata *udata)
>> +{
>> +	struct irdma_pd *iwpd = to_iwpd(pd);
>> +	struct irdma_device *iwdev = to_iwdev(pd->device);
>> +	struct irdma_sc_dev *dev = &iwdev->rf->sc_dev;
>> +	struct irdma_pci_f *rf = iwdev->rf;
>> +	struct irdma_alloc_pd_resp uresp = {};
>> +	struct irdma_sc_pd *sc_pd;
>> +	struct irdma_ucontext *ucontext;
>> +	u32 pd_id = 0;
>> +	int err;
>> +
>> +	if (iwdev->closing)
>> +		return -ENODEV;
>> +
>> +	err = irdma_alloc_rsrc(rf, rf->allocated_pds, rf->max_pd, &pd_id,
>> +			       &rf->next_pd);
>> +	if (err)
>> +		return err;
>> +
>> +	sc_pd = &iwpd->sc_pd;
>> +	if (context) {
>
>I think this should be 'if (udata)', this applies to many other places in this driver.

That’s right. Will fix it.

>
>> +		ucontext = to_ucontext(context);
>> +		dev->iw_pd_ops->pd_init(dev, sc_pd, pd_id, ucontext->abi_ver);
>> +		uresp.pd_id = pd_id;
>> +		if (ib_copy_to_udata(udata, &uresp, sizeof(uresp))) {
>> +			err = -EFAULT;
>> +			goto error;
>> +		}
>> +	} else {
>> +		dev->iw_pd_ops->pd_init(dev, sc_pd, pd_id, -1);
>> +	}
>> +
>> +	irdma_add_pdusecount(iwpd);
>> +
>> +	return 0;
>> +error:
>> +	irdma_free_rsrc(rf, rf->allocated_pds, pd_id);
>> +
>> +	return err;
>> +}
>> +/**
>> + * irdma_create_qp - create qp
>> + * @ibpd: ptr of pd
>> + * @init_attr: attributes for qp
>> + * @udata: user data for create qp
>> + */
>> +static struct ib_qp *irdma_create_qp(struct ib_pd *ibpd,
>> +				     struct ib_qp_init_attr *init_attr,
>> +				     struct ib_udata *udata)
>> +{
>> +	struct irdma_pd *iwpd = to_iwpd(ibpd);
>> +	struct irdma_device *iwdev = to_iwdev(ibpd->device);
>> +	struct irdma_pci_f *rf = iwdev->rf;
>> +	struct irdma_cqp *iwcqp = &rf->cqp;
>> +	struct irdma_qp *iwqp;
>> +	struct irdma_ucontext *ucontext;
>> +	struct irdma_create_qp_req req;
>> +	struct irdma_create_qp_resp uresp = {};
>> +	struct i40iw_create_qp_resp uresp_gen1 = {};
>> +	u32 qp_num = 0;
>> +	void *mem;
>> +	enum irdma_status_code ret;
>> +	int err_code = 0;
>> +	int sq_size;
>> +	int rq_size;
>> +	struct irdma_sc_qp *qp;
>> +	struct irdma_sc_dev *dev = &rf->sc_dev;
>> +	struct irdma_qp_init_info init_info = {};
>> +	struct irdma_create_qp_info *qp_info;
>> +	struct irdma_cqp_request *cqp_request;
>> +	struct cqp_cmds_info *cqp_info;
>> +	struct irdma_qp_host_ctx_info *ctx_info;
>> +	struct irdma_iwarp_offload_info *iwarp_info;
>> +	struct irdma_roce_offload_info *roce_info;
>> +	struct irdma_udp_offload_info *udp_info;
>> +	unsigned long flags;
>> +
>> +	if (iwdev->closing)
>> +		return ERR_PTR(-ENODEV);
>> +
>> +	if (init_attr->create_flags)
>> +		return ERR_PTR(-EINVAL);
>> +
>> +	if (init_attr->cap.max_inline_data > dev->hw_attrs.max_hw_inline)
>> +		init_attr->cap.max_inline_data = dev->hw_attrs.max_hw_inline;
>> +
>> +	if (init_attr->cap.max_send_sge > dev->hw_attrs.max_hw_wq_frags)
>> +		init_attr->cap.max_send_sge = dev-
>>hw_attrs.max_hw_wq_frags;
>> +
>> +	if (init_attr->cap.max_recv_sge > dev->hw_attrs.max_hw_wq_frags)
>> +		init_attr->cap.max_recv_sge = dev->hw_attrs.max_hw_wq_frags;
>
>AFAIK, you can change the requested values to be greater than or equal to the
>values requested. I don't think you can change them to something smaller.

Hmm...This is a sanity check to make sure we don’t exceed the device supported values.
But we should fail the call.

[..]

>> +	mem = kzalloc(sizeof(*iwqp), GFP_KERNEL);
>> +	if (!mem)
>> +		return ERR_PTR(-ENOMEM);
>> +
>> +	iwqp = (struct irdma_qp *)mem;
>> +	iwqp->allocated_buf = mem;
>
>'allocated_buf' feels redundant. Why is iwqp not sufficient?

I agree.
[..]

>> +	if (udata) {
>> +		err_code = ib_copy_from_udata(&req, udata, sizeof(req));
>
>Perhaps ib_copy_from_udata(&req, udata, min(sizeof(req), udata->inlen)?
>Applies to other call sites of ib_copy_from/to_udata as well.
>

It’s a good idea.

>> + * irdma_query - query qp attributes
>> + * @ibqp: qp pointer
>> + * @attr: attributes pointer
>> + * @attr_mask: Not used
>> + * @init_attr: qp attributes to return  */ static int
>> +irdma_query_qp(struct ib_qp *ibqp,
>> +			  struct ib_qp_attr *attr,
>> +			  int attr_mask,
>> +			  struct ib_qp_init_attr *init_attr) {
>> +	struct irdma_qp *iwqp = to_iwqp(ibqp);
>> +	struct irdma_sc_qp *qp = &iwqp->sc_qp;
>> +
>> +	attr->qp_state = iwqp->ibqp_state;
>> +	attr->cur_qp_state = iwqp->ibqp_state;
>> +	attr->qp_access_flags = 0;
>> +	attr->cap.max_send_wr = qp->qp_uk.sq_size - 1;
>> +	attr->cap.max_recv_wr = qp->qp_uk.rq_size - 1;
>
>Why -1?

It's reserved for HW. But the equation should be 
(sqdepth - I40IW_SQ_RSVD) >> sqshift.

[....]
>
>> +	attr->cap.max_inline_data = qp->qp_uk.max_inline_data;
>> +	attr->cap.max_send_sge = qp->qp_uk.max_sq_frag_cnt;
>> +	attr->cap.max_recv_sge = qp->qp_uk.max_rq_frag_cnt;
>> +	attr->qkey = iwqp->roce_info.qkey;
>> +
>> +	init_attr->event_handler = iwqp->ibqp.event_handler;
>> +	init_attr->qp_context = iwqp->ibqp.qp_context;
>> +	init_attr->send_cq = iwqp->ibqp.send_cq;
>> +	init_attr->recv_cq = iwqp->ibqp.recv_cq;
>> +	init_attr->srq = iwqp->ibqp.srq;
>> +	init_attr->cap = attr->cap;
>> +
>> +	return 0;
>> +}
>> +
>> +/**
>> + * irdma_destroy_cq - destroy cq
>> + * @ib_cq: cq pointer
>> + */
>> +static int irdma_destroy_cq(struct ib_cq *ib_cq) {
>> +	struct irdma_cq *iwcq;
>> +	struct irdma_device *iwdev;
>> +	struct irdma_sc_cq *cq;
>> +
>> +	if (!ib_cq) {
>> +		irdma_pr_err("ib_cq == NULL\n");
>> +		return 0;
>> +	}
>
>Is this really needed? Which caller can pass NULL pointer?

Not needed.

>> +
>> +/**
>> + * board_id_show
>> + */
>> +static ssize_t board_id_show(struct device *dev,
>> +			     struct device_attribute *attr,
>> +			     char *buf)
>> +{
>> +	return sprintf(buf, "%.*s\n", 32, "IRDMA Board ID");
>
>That doesn't add much information.

Will fix.

>
>> +}
>> +
>> +static DEVICE_ATTR_RO(hw_rev);
>> +static DEVICE_ATTR_RO(hca_type);
>> +static DEVICE_ATTR_RO(board_id);
>> +
>> +static struct attribute *irdma_dev_attributes[] = {
>> +	&dev_attr_hw_rev.attr,
>> +	&dev_attr_hca_type.attr,
>> +	&dev_attr_board_id.attr,
>> +	NULL
>> +};
>> +
>> +static const struct attribute_group irdma_attr_group = {
>> +	.attrs = irdma_dev_attributes,
>> +};
>> +
>> +/**
>> + * irdma_modify_port  Modify port properties
>> + * @ibdev: device pointer from stack
>> + * @port: port number
>> + * @port_modify_mask: mask for port modifications
>> + * @props: port properties
>> + */
>> +static int irdma_modify_port(struct ib_device *ibdev,
>> +			     u8 port,
>> +			     int port_modify_mask,
>> +			     struct ib_port_modify *props) {
>> +	return 0;
>> +}
>
>Same question as disacossiate_ucontext.

This was likely added during early dev. and can be removed.

>
>> +
>> +/**
>> + * irdma_query_gid_roce - Query port GID for Roce
>> + * @ibdev: device pointer from stack
>> + * @port: port number
>> + * @index: Entry index
>> + * @gid: Global ID
>> + */
>> +static int irdma_query_gid_roce(struct ib_device *ibdev,
>> +				u8 port,
>> +				int index,
>> +				union ib_gid *gid)
>> +{
>> +	int ret;
>> +
>> +	ret = rdma_query_gid(ibdev, port, index, gid);
>> +	if (ret == -EAGAIN) {
>
>I can't see a path where rdma_query_gid returns -EAGAIN.

This function can be removed now. It's only applicable to non-Roce providers.

>
>> +		memcpy(gid, &zgid, sizeof(*gid));
>> +		return 0;
>> +	}
>> +
>> +	return ret;
>> +}
>> +
>
>> +/**
>> + * irdma_create_ah - create address handle
>> + * @ibpd: ptr to protection domain
>> + * @ah_attr: address handle attributes
>
>'ah_attr' -> 'attr', missing flags and udata.

Will fix all these hits in the driver.

[..]
>> + */
>> +static int irdma_destroy_ah(struct ib_ah *ibah, u32 flags) {
>> +	struct irdma_device *iwdev = to_iwdev(ibah->device);
>> +	struct irdma_ah *ah = to_iwah(ibah);
>> +	int err;
>> +
>> +	if (!ah->sc_ah.ah_info.ah_valid)
>> +		return -EINVAL;
>> +
>> +	err = irdma_ah_cqp_op(iwdev->rf, &ah->sc_ah,
>IRDMA_OP_AH_DESTROY,
>> +			      flags & RDMA_DESTROY_AH_SLEEPABLE,
>> +			      irdma_destroy_ah_cb, ah);
>> +	if (!err)
>> +		return 0;
>
>Why are the rest of the cleanups only in case of error?

On success, the cleanup is done in the callback, irdma_destroy_ah_cb.

[...]


>> +static __be64 irdma_mac_to_guid(struct net_device *ndev) {
>> +	unsigned char *mac = ndev->dev_addr;
>> +	__be64 guid;
>> +	unsigned char *dst = (unsigned char *)&guid;
>> +
>> +	dst[0] = mac[0] ^ 2;
>> +	dst[1] = mac[1];
>> +	dst[2] = mac[2];
>> +	dst[3] = 0xff;
>> +	dst[4] = 0xfe;
>> +	dst[5] = mac[3];
>> +	dst[6] = mac[4];
>> +	dst[7] = mac[5];
>> +
>> +	return guid;
>> +}
>
>There's a variant of this function in irdma, bnxt_re, ocrdma and qedr.
>Maybe it's time to provide it in common code?

Agreed.