[SCSI] bfa: Introduced generic address len pair to represent DMA memory chunk.

- Avoid the use of hardware defined structure bfi_sge_s for DMA
  requests in host.

- Defined a generic address len pair to represent a DMA memory chunk
  (bfi_alen_s).
Signed-off-by: Krishna Gudipati <kgudipat@brocade.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

drivers/scsi/bfa/bfa_ioc.h

@@ -112,18 +112,6 @@ struct bfa_dma_s {
 #define BFI_SMEM_CB_SIZE	0x200000U	/* ! 2MB for crossbow	*/
 #define BFI_SMEM_CT_SIZE	0x280000U	/* ! 2.5MB for catapult	*/
 
-
-#define bfa_dma_addr_set(dma_addr, pa)	\
-		__bfa_dma_addr_set(&dma_addr, (u64)pa)
-
-static inline void
-__bfa_dma_addr_set(union bfi_addr_u *dma_addr, u64 pa)
-{
-	dma_addr->a32.addr_lo = (__be32) pa;
-	dma_addr->a32.addr_hi = (__be32) (pa >> 32);
-}
-
-
 #define bfa_dma_be_addr_set(dma_addr, pa)	\
 		__bfa_dma_be_addr_set(&dma_addr, (u64)pa)
 static inline void
@@ -133,6 +121,16 @@ __bfa_dma_be_addr_set(union bfi_addr_u *dma_addr, u64 pa)
 	dma_addr->a32.addr_hi = cpu_to_be32(pa >> 32);
 }
 
+#define bfa_alen_set(__alen, __len, __pa)	\
+	__bfa_alen_set(__alen, __len, (u64)__pa)
+
+static inline void
+__bfa_alen_set(struct bfi_alen_s *alen, u32 len, u64 pa)
+{
+	alen->al_len = cpu_to_be32(len);
+	bfa_dma_be_addr_set(alen->al_addr, pa);
+}
+
 struct bfa_ioc_regs_s {
 	void __iomem *hfn_mbox_cmd;
 	void __iomem *hfn_mbox;

drivers/scsi/bfa/bfa_svc.c

@@ -749,23 +749,6 @@ hal_fcxp_send_comp(struct bfa_s *bfa, struct bfi_fcxp_send_rsp_s *fcxp_rsp)
 	}
 }
 
-static void
-hal_fcxp_set_local_sges(struct bfi_sge_s *sge, u32 reqlen, u64 req_pa)
-{
-	union bfi_addr_u      sga_zero = { {0} };
-
-	sge->sg_len = reqlen;
-	sge->flags = BFI_SGE_DATA_LAST;
-	bfa_dma_addr_set(sge[0].sga, req_pa);
-	bfa_sge_to_be(sge);
-	sge++;
-
-	sge->sga = sga_zero;
-	sge->sg_len = reqlen;
-	sge->flags = BFI_SGE_PGDLEN;
-	bfa_sge_to_be(sge);
-}
-
 static void
 hal_fcxp_tx_plog(struct bfa_s *bfa, u32 reqlen, struct bfa_fcxp_s *fcxp,
 		 struct fchs_s *fchs)
@@ -873,18 +856,16 @@ bfa_fcxp_queue(struct bfa_fcxp_s *fcxp, struct bfi_fcxp_send_req_s *send_req)
 	 * setup req sgles
 	 */
 	if (fcxp->use_ireqbuf == 1) {
-		hal_fcxp_set_local_sges(send_req->req_sge, reqi->req_tot_len,
+		bfa_alen_set(&send_req->req_alen, reqi->req_tot_len,
 					BFA_FCXP_REQ_PLD_PA(fcxp));
 	} else {
 		if (fcxp->nreq_sgles > 0) {
 			WARN_ON(fcxp->nreq_sgles != 1);
-			hal_fcxp_set_local_sges(send_req->req_sge,
-						reqi->req_tot_len,
-						fcxp->req_sga_cbfn(fcxp->caller,
-								   0));
+			bfa_alen_set(&send_req->req_alen, reqi->req_tot_len,
+				fcxp->req_sga_cbfn(fcxp->caller, 0));
 		} else {
 			WARN_ON(reqi->req_tot_len != 0);
-			hal_fcxp_set_local_sges(send_req->rsp_sge, 0, 0);
+			bfa_alen_set(&send_req->rsp_alen, 0, 0);
 		}
 	}
 
@@ -894,19 +875,17 @@ bfa_fcxp_queue(struct bfa_fcxp_s *fcxp, struct bfi_fcxp_send_req_s *send_req)
 	if (fcxp->use_irspbuf == 1) {
 		WARN_ON(rspi->rsp_maxlen > BFA_FCXP_MAX_LBUF_SZ);
 
-		hal_fcxp_set_local_sges(send_req->rsp_sge, rspi->rsp_maxlen,
+		bfa_alen_set(&send_req->rsp_alen, rspi->rsp_maxlen,
 					BFA_FCXP_RSP_PLD_PA(fcxp));
-
 	} else {
 		if (fcxp->nrsp_sgles > 0) {
 			WARN_ON(fcxp->nrsp_sgles != 1);
-			hal_fcxp_set_local_sges(send_req->rsp_sge,
-						rspi->rsp_maxlen,
-						fcxp->rsp_sga_cbfn(fcxp->caller,
-								   0));
+			bfa_alen_set(&send_req->rsp_alen, rspi->rsp_maxlen,
+				fcxp->rsp_sga_cbfn(fcxp->caller, 0));
+
 		} else {
 			WARN_ON(rspi->rsp_maxlen != 0);
-			hal_fcxp_set_local_sges(send_req->rsp_sge, 0, 0);
+			bfa_alen_set(&send_req->rsp_alen, 0, 0);
 		}
 	}
 
@@ -4801,8 +4780,6 @@ static void
 claim_uf_post_msgs(struct bfa_uf_mod_s *ufm, struct bfa_meminfo_s *mi)
 {
 	struct bfi_uf_buf_post_s *uf_bp_msg;
-	struct bfi_sge_s      *sge;
-	union bfi_addr_u      sga_zero = { {0} };
 	u16 i;
 	u16 buf_len;
 
@@ -4818,17 +4795,7 @@ claim_uf_post_msgs(struct bfa_uf_mod_s *ufm, struct bfa_meminfo_s *mi)
 		uf_bp_msg->buf_len = cpu_to_be16(buf_len);
 		bfi_h2i_set(uf_bp_msg->mh, BFI_MC_UF, BFI_UF_H2I_BUF_POST,
 			    bfa_lpuid(ufm->bfa));
-
-		sge = uf_bp_msg->sge;
-		sge[0].sg_len = buf_len;
-		sge[0].flags = BFI_SGE_DATA_LAST;
-		bfa_dma_addr_set(sge[0].sga, ufm_pbs_pa(ufm, i));
-		bfa_sge_to_be(sge);
-
-		sge[1].sg_len = buf_len;
-		sge[1].flags = BFI_SGE_PGDLEN;
-		sge[1].sga = sga_zero;
-		bfa_sge_to_be(&sge[1]);
+		bfa_alen_set(&uf_bp_msg->alen, buf_len, ufm_pbs_pa(ufm, i));
 	}
 
 	/*

drivers/scsi/bfa/bfi.h

@@ -101,7 +101,7 @@ union bfi_addr_u {
 };
 
 /*
- * Scatter Gather Element
+ * Scatter Gather Element used for fast-path IO requests
  */
 struct bfi_sge_s {
 #ifdef __BIG_ENDIAN
@@ -116,6 +116,14 @@ struct bfi_sge_s {
 	union bfi_addr_u sga;
 };
 
+/**
+ * Generic DMA addr-len pair.
+ */
+struct bfi_alen_s {
+	union bfi_addr_u	al_addr;	/* DMA addr of buffer	*/
+	u32			al_len;		/* length of buffer	*/
+};
+
 /*
  * Scatter Gather Page
  */

drivers/scsi/bfa/bfi_ms.h

@@ -297,8 +297,8 @@ struct bfi_fcxp_send_req_s {
 	struct fchs_s	fchs;	/*  request FC header structure    */
 	__be32	req_len;	/*  request payload length	    */
 	__be32	rsp_maxlen;	/*  max response length expected   */
-	struct bfi_sge_s   req_sge[BFA_FCXP_MAX_SGES];	/*  request buf    */
-	struct bfi_sge_s   rsp_sge[BFA_FCXP_MAX_SGES];	/*  response buf   */
+	struct bfi_alen_s req_alen;	/* request buffer	*/
+	struct bfi_alen_s rsp_alen;	/* response buffer	*/
 };
 
 /*
@@ -328,7 +328,7 @@ struct bfi_uf_buf_post_s {
 	struct bfi_mhdr_s  mh;		/*  Common msg header		*/
 	u16	buf_tag;	/*  buffer tag			*/
 	__be16	buf_len;	/*  total buffer length	*/
-	struct bfi_sge_s   sge[BFA_UF_MAX_SGES]; /*  buffer DMA SGEs	*/
+	struct bfi_alen_s alen;	/* buffer address/len pair	*/
 };
 
 struct bfi_uf_frm_rcvd_s {