Merge patch series "qla2xxx driver misc features"

Nilesh Javali <njavali@marvell.com> says:

Martin,

Please apply the qla2xxx driver miscellaneous features and bug fixes
to the scsi tree at your earliest convenience.

Link: https://lore.kernel.org/r/20230821130045.34850-1-njavali@marvell.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 56 insertions, 1 deletions

diff --git a/drivers/scsi/qla2xxx/qla_inline.h b/drivers/scsi/qla2xxx/qla_inline.h
index 0167e85ba058..0556969f6dc1 100644
--- a/drivers/scsi/qla2xxx/qla_inline.h
+++ b/drivers/scsi/qla2xxx/qla_inline.h
@@ -386,6 +386,7 @@ enum {
 	RESOURCE_IOCB = BIT_0,
 	RESOURCE_EXCH = BIT_1,  /* exchange */
 	RESOURCE_FORCE = BIT_2,
+	RESOURCE_HA = BIT_3,
 };
 
 static inline int
@@ -393,7 +394,7 @@ qla_get_fw_resources(struct qla_qpair *qp, struct iocb_resource *iores)
 {
 	u16 iocbs_used, i;
 	u16 exch_used;
-	struct qla_hw_data *ha = qp->vha->hw;
+	struct qla_hw_data *ha = qp->hw;
 
 	if (!ql2xenforce_iocb_limit) {
 		iores->res_type = RESOURCE_NONE;
@@ -428,15 +429,69 @@ qla_get_fw_resources(struct qla_qpair *qp, struct iocb_resource *iores)
 			return -ENOSPC;
 		}
 	}
+
+	if (ql2xenforce_iocb_limit == 2) {
+		if ((iores->iocb_cnt + atomic_read(&ha->fwres.iocb_used)) >=
+		    ha->fwres.iocb_limit) {
+			iores->res_type = RESOURCE_NONE;
+			return -ENOSPC;
+		}
+
+		if (iores->res_type & RESOURCE_EXCH) {
+			if ((iores->exch_cnt + atomic_read(&ha->fwres.exch_used)) >=
+			    ha->fwres.exch_limit) {
+				iores->res_type = RESOURCE_NONE;
+				return -ENOSPC;
+			}
+		}
+	}
+
 force:
 	qp->fwres.iocbs_used += iores->iocb_cnt;
 	qp->fwres.exch_used += iores->exch_cnt;
+	if (ql2xenforce_iocb_limit == 2) {
+		atomic_add(iores->iocb_cnt, &ha->fwres.iocb_used);
+		atomic_add(iores->exch_cnt, &ha->fwres.exch_used);
+		iores->res_type |= RESOURCE_HA;
+	}
 	return 0;
 }
 
+/*
+ * decrement to zero.  This routine will not decrement below zero
+ * @v:  pointer of type atomic_t
+ * @amount: amount to decrement from v
+ */
+static void qla_atomic_dtz(atomic_t *v, int amount)
+{
+	int c, old, dec;
+
+	c = atomic_read(v);
+	for (;;) {
+		dec = c - amount;
+		if (unlikely(dec < 0))
+			dec = 0;
+
+		old = atomic_cmpxchg((v), c, dec);
+		if (likely(old == c))
+			break;
+		c = old;
+	}
+}
+
 static inline void
 qla_put_fw_resources(struct qla_qpair *qp, struct iocb_resource *iores)
 {
+	struct qla_hw_data *ha = qp->hw;
+
+	if (iores->res_type & RESOURCE_HA) {
+		if (iores->res_type & RESOURCE_IOCB)
+			qla_atomic_dtz(&ha->fwres.iocb_used, iores->iocb_cnt);
+
+		if (iores->res_type & RESOURCE_EXCH)
+			qla_atomic_dtz(&ha->fwres.exch_used, iores->exch_cnt);
+	}
+
 	if (iores->res_type & RESOURCE_IOCB) {
 		if (qp->fwres.iocbs_used >= iores->iocb_cnt) {
 			qp->fwres.iocbs_used -= iores->iocb_cnt;