Commit a15af54f authored by Gavin Shan's avatar Gavin Shan Committed by David S. Miller
Browse files

net/ncsi: Rework request index allocation 



The NCSI request index (struct ncsi_request::id) is put into instance
ID (IID) field while sending NCSI command packet. It was designed the
available IDs are given in round-robin fashion. @ndp->request_id was
introduced to represent the next available ID, but it has been used
as number of successively allocated IDs. It breaks the round-robin
design. Besides, we shouldn't put 0 to NCSI command packet's IID
field, meaning ID#0 should be reserved according section 6.3.1.1
in NCSI spec (v1.1.0).

This fixes above two issues. With it applied, the available IDs will
be assigned in round-robin fashion and ID#0 won't be assigned.

Signed-off-by: default avatarGavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: default avatarJoel Stanley <joel@jms.id.au>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 55e02d08

net/ncsi/internal.h

+1 −0
Original line number Diff line number Diff line
@@ -259,6 +259,7 @@ struct ncsi_dev_priv { 
	struct list_head    packages;        /* List of packages           */

	struct ncsi_request requests[256];   /* Request table              */

	unsigned int        request_id;      /* Last used request ID       */

#define NCSI_REQ_START_IDX	1

	unsigned int        pending_req_num; /* Number of pending requests */

	struct ncsi_package *active_package; /* Currently handled package  */

	struct ncsi_channel *active_channel; /* Currently handled channel  */

net/ncsi/ncsi-manage.c

+9 −8
Original line number Diff line number Diff line
@@ -427,30 +427,31 @@ struct ncsi_request *ncsi_alloc_request(struct ncsi_dev_priv *ndp, bool driven) 


	/* Check if there is one available request until the ceiling */

	spin_lock_irqsave(&ndp->lock, flags);

	for (i = ndp->request_id; !nr && i < limit; i++) {

	for (i = ndp->request_id; i < limit; i++) {

		if (ndp->requests[i].used)

			continue;



		nr = &ndp->requests[i];

		nr->used = true;

		nr->driven = driven;

		if (++ndp->request_id >= limit)

			ndp->request_id = 0;

		ndp->request_id = i + 1;

		goto found;

	}



	/* Fail back to check from the starting cursor */

	for (i = 0; !nr && i < ndp->request_id; i++) {

	for (i = NCSI_REQ_START_IDX; i < ndp->request_id; i++) {

		if (ndp->requests[i].used)

			continue;



		nr = &ndp->requests[i];

		nr->used = true;

		nr->driven = driven;

		if (++ndp->request_id >= limit)

			ndp->request_id = 0;

		ndp->request_id = i + 1;

		goto found;

	}

	spin_unlock_irqrestore(&ndp->lock, flags);



found:

	spin_unlock_irqrestore(&ndp->lock, flags);

	return nr;

}
@@ -1148,7 +1149,7 @@ struct ncsi_dev *ncsi_register_dev(struct net_device *dev, 
	/* Initialize private NCSI device */

	spin_lock_init(&ndp->lock);

	INIT_LIST_HEAD(&ndp->packages);

	ndp->request_id = 0;

	ndp->request_id = NCSI_REQ_START_IDX;

	for (i = 0; i < ARRAY_SIZE(ndp->requests); i++) {

		ndp->requests[i].id = i;

		ndp->requests[i].ndp = ndp;

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