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: Gavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ncsi/ncsi-manage.c b/net/ncsi/ncsi-manage.c
index 8c5e016..00ce2c7 100644
--- a/net/ncsi/ncsi-manage.c
+++ b/net/ncsi/ncsi-manage.c
@@ -427,30 +427,31 @@
/* 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 @@
/* 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;