[PATCH 6.18.y 1/2] scsi: qla2xxx: Use ring-slot helpers in __qla2x00_alloc_iocbs

[Sasha Levin <sashal@kernel.org>]

From: Nilesh Javali <njavali@marvell.com>

[ Upstream commit 7e51b6d2d8f6b7f48d9cef1cf87471b55b12f6de ]

__qla2x00_alloc_iocbs() open-codes ring pointer selection and entry size
based on IS_QLA29XX(ha): 29xx reaches the slot via ring_ext_ptr and
zeroes REQUEST_ENTRY_SIZE_EXT bytes, while other adapters use ring_ptr
with REQUEST_ENTRY_SIZE bytes.

Replace the two branches with the qla_req_ring_slot() and
qla_req_entry_size() helpers, and initialise pkt at declaration.  The
IS_QLAFX00 register-mapped writes remain guarded because IS_QLAFX00 and
IS_QLA29XX cannot be true simultaneously.

No functional change: the bytes written to the firmware-visible IOCB are
identical.

Signed-off-by: Nilesh Javali <njavali@marvell.com>
Reviewed-by: Hannes Reinecke <hare@kernel.org>
Link: https://patch.msgid.link/20260723050413.3897522-24-njavali@marvell.com
Signed-off-by: Martin K. Petersen (Oracle) <mkp@kernel.org>

Stable adaptation:
This tree has no QLA29xx support, extended request ring, or ring-slot
helpers. Provide file-local macro helpers mapping to req->ring_ptr and
REQUEST_ENTRY_SIZE, preserving the existing 64-byte ring behavior without
adding functions or importing the unrelated QLA29xx support series.

Retain the helper calls and declaration initialization from this change.
Use a multiline packet-preparation comment so commit 626e44f3d8a9
("scsi: qla2xxx: Use memset_io() to clear QLAFX00 request ring slot")
applies unchanged, including its leading context. That commit remains
responsible for changing the FX00 clearing operation to memset_io().

Stable-dep-of: 626e44f3d8a9 ("scsi: qla2xxx: Use memset_io() to clear QLAFX00 request ring slot")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/scsi/qla2xxx/qla_iocb.c | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/drivers/scsi/qla2xxx/qla_iocb.c b/drivers/scsi/qla2xxx/qla_iocb.c
index 3224044f17753..3a97973ed26ac 100644
--- a/drivers/scsi/qla2xxx/qla_iocb.c
+++ b/drivers/scsi/qla2xxx/qla_iocb.c
@@ -11,6 +11,10 @@
 
 #include <scsi/scsi_tcq.h>
 
+/* All adapters supported by this tree use the 64-byte request ring. */
+#define qla_req_ring_slot(ha, req) ((req)->ring_ptr)
+#define qla_req_entry_size(ha) REQUEST_ENTRY_SIZE
+
 static int qla_start_scsi_type6(srb_t *sp);
 /**
  * qla2x00_get_cmd_direction() - Determine control_flag data direction.
@@ -2286,10 +2290,9 @@ __qla2x00_alloc_iocbs(struct qla_qpair *qpair, srb_t *sp)
 	struct req_que *req = qpair->req;
 	device_reg_t *reg = ISP_QUE_REG(ha, req->id);
 	uint32_t handle;
-	request_t *pkt;
 	uint16_t cnt, req_cnt;
+	request_t *pkt = NULL;
 
-	pkt = NULL;
 	req_cnt = 1;
 	handle = 0;
 
@@ -2343,10 +2346,12 @@ __qla2x00_alloc_iocbs(struct qla_qpair *qpair, srb_t *sp)
 		sp->handle = handle;
 	}
 
-	/* Prep packet */
+	/*
+	 * Prep the current request-ring slot.
+	 */
 	req->cnt -= req_cnt;
-	pkt = req->ring_ptr;
-	memset(pkt, 0, REQUEST_ENTRY_SIZE);
+	pkt = qla_req_ring_slot(ha, req);
+	memset(pkt, 0, qla_req_entry_size(ha));
 	if (IS_QLAFX00(ha)) {
 		wrt_reg_byte((u8 __force __iomem *)&pkt->entry_count, req_cnt);
 		wrt_reg_dword((__le32 __force __iomem *)&pkt->handle, handle);
-- 
2.53.0