[SCSI] bfa: scatter gather processing change

Modified scatter gather processing to use the kernel provided
scsi_for_each_sg() macro.

1) Instead of allocating and setting up sgpg in bfa_ioim_sge_setup(),
   we only do allocation.  As a result, we remove
   bfa_ioim_sgpg_setup() and rename bfa_ioim_sge_setup() to
   bfa_ioim_sgpg_alloc().

2) bfa_ioim_send_ioreq() call scsi_for_each_sg() to handle both inline
   and sgpg setup.

Signed-off-by: Maggie Zhang <xmzhang@brocade.com>
Signed-off-by: Jing Huang <huangj@brocade.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

1 files changed, 59 insertions, 81 deletions

diff --git a/drivers/scsi/bfa/bfa_fcpim.c b/drivers/scsi/bfa/bfa_fcpim.c
index d6aea5d4425f..c07ee42345bc 100644
--- a/drivers/scsi/bfa/bfa_fcpim.c
+++ b/drivers/scsi/bfa/bfa_fcpim.c
@@ -218,8 +218,7 @@ static void     bfa_itnim_sm_deleting_qfull(struct bfa_itnim_s *itnim,
  * forward declaration for BFA IOIM functions
  */
 static bfa_boolean_t    bfa_ioim_send_ioreq(struct bfa_ioim_s *ioim);
-static bfa_boolean_t    bfa_ioim_sge_setup(struct bfa_ioim_s *ioim);
-static void             bfa_ioim_sgpg_setup(struct bfa_ioim_s *ioim);
+static bfa_boolean_t    bfa_ioim_sgpg_alloc(struct bfa_ioim_s *ioim);
 static bfa_boolean_t    bfa_ioim_send_abort(struct bfa_ioim_s *ioim);
 static void             bfa_ioim_notify_cleanup(struct bfa_ioim_s *ioim);
 static void __bfa_cb_ioim_good_comp(void *cbarg, bfa_boolean_t complete);
@@ -1621,7 +1620,7 @@ bfa_ioim_sm_uninit(struct bfa_ioim_s *ioim, enum bfa_ioim_event event)
                 }
 
                 if (ioim->nsges > BFI_SGE_INLINE) {
-                        if (!bfa_ioim_sge_setup(ioim)) {
+                        if (!bfa_ioim_sgpg_alloc(ioim)) {
                                 bfa_sm_set_state(ioim, bfa_ioim_sm_sgalloc);
                                 return;
                         }
@@ -2304,7 +2303,7 @@ bfa_ioim_sgpg_alloced(void *cbarg)
 
         ioim->nsgpgs = BFA_SGPG_NPAGE(ioim->nsges);
         list_splice_tail_init(&ioim->iosp->sgpg_wqe.sgpg_q, &ioim->sgpg_q);
-        bfa_ioim_sgpg_setup(ioim);
+        ioim->sgpg = bfa_q_first(&ioim->sgpg_q);
         bfa_sm_send_event(ioim, BFA_IOIM_SM_SGALLOCED);
 }
 
@@ -2317,12 +2316,14 @@ bfa_ioim_send_ioreq(struct bfa_ioim_s *ioim)
         struct bfa_itnim_s *itnim = ioim->itnim;
         struct bfi_ioim_req_s *m;
         static struct fcp_cmnd_s cmnd_z0 = { 0 };
-        struct bfi_sge_s      *sge;
+        struct bfi_sge_s *sge, *sgpge;
         u32     pgdlen = 0;
         u32     fcp_dl;
         u64 addr;
         struct scatterlist *sg;
+        struct bfa_sgpg_s *sgpg;
         struct scsi_cmnd *cmnd = (struct scsi_cmnd *) ioim->dio;
+        u32 i, sge_id, pgcumsz;
 
         /*
          * check for room in queue to send request now
@@ -2342,20 +2343,59 @@ bfa_ioim_send_ioreq(struct bfa_ioim_s *ioim)
         m->rport_hdl = ioim->itnim->rport->fw_handle;
         m->io_timeout = bfa_cb_ioim_get_timeout(ioim->dio);
 
-        /*
-         * build inline IO SG element here
-         */
         sge = &m->sges[0];
-        if (ioim->nsges) {
-                sg = (struct scatterlist *)scsi_sglist(cmnd);
-                addr = bfa_os_sgaddr(sg_dma_address(sg));
-                sge->sga = *(union bfi_addr_u *) &addr;
-                pgdlen = sg_dma_len(sg);
-                sge->sg_len = pgdlen;
-                sge->flags = (ioim->nsges > BFI_SGE_INLINE) ?
+        sgpg = ioim->sgpg;
+        sge_id = 0;
+        sgpge = NULL;
+        pgcumsz = 0;
+        scsi_for_each_sg(cmnd, sg, ioim->nsges, i) {
+                if (i == 0) {
+                        /* build inline IO SG element */
+                        addr = bfa_os_sgaddr(sg_dma_address(sg));
+                        sge->sga = *(union bfi_addr_u *) &addr;
+                        pgdlen = sg_dma_len(sg);
+                        sge->sg_len = pgdlen;
+                        sge->flags = (ioim->nsges > BFI_SGE_INLINE) ?
                                         BFI_SGE_DATA_CPL : BFI_SGE_DATA_LAST;
-                bfa_sge_to_be(sge);
-                sge++;
+                        bfa_sge_to_be(sge);
+                        sge++;
+                } else {
+                        if (sge_id == 0)
+                                sgpge = sgpg->sgpg->sges;
+
+                        addr = bfa_os_sgaddr(sg_dma_address(sg));
+                        sgpge->sga = *(union bfi_addr_u *) &addr;
+                        sgpge->sg_len = sg_dma_len(sg);
+                        pgcumsz += sgpge->sg_len;
+
+                        /* set flags */
+                        if (i < (ioim->nsges - 1) &&
+                                        sge_id < (BFI_SGPG_DATA_SGES - 1))
+                                sgpge->flags = BFI_SGE_DATA;
+                        else if (i < (ioim->nsges - 1))
+                                sgpge->flags = BFI_SGE_DATA_CPL;
+                        else
+                                sgpge->flags = BFI_SGE_DATA_LAST;
+
+                        bfa_sge_to_le(sgpge);
+
+                        sgpge++;
+                        if (i == (ioim->nsges - 1)) {
+                                sgpge->flags = BFI_SGE_PGDLEN;
+                                sgpge->sga.a32.addr_lo = 0;
+                                sgpge->sga.a32.addr_hi = 0;
+                                sgpge->sg_len = pgcumsz;
+                                bfa_sge_to_le(sgpge);
+                        } else if (++sge_id == BFI_SGPG_DATA_SGES) {
+                                sgpg = (struct bfa_sgpg_s *) bfa_q_next(sgpg);
+                                sgpge->flags = BFI_SGE_LINK;
+                                sgpge->sga = sgpg->sgpg_pa;
+                                sgpge->sg_len = pgcumsz;
+                                bfa_sge_to_le(sgpge);
+                                sge_id = 0;
+                                pgcumsz = 0;
+                        }
+                }
         }
 
         if (ioim->nsges > BFI_SGE_INLINE) {
@@ -2414,7 +2454,7 @@ bfa_ioim_send_ioreq(struct bfa_ioim_s *ioim)
  * at queuing time.
  */
 static bfa_boolean_t
-bfa_ioim_sge_setup(struct bfa_ioim_s *ioim)
+bfa_ioim_sgpg_alloc(struct bfa_ioim_s *ioim)
 {
         u16     nsgpgs;
 
@@ -2434,73 +2474,11 @@ bfa_ioim_sge_setup(struct bfa_ioim_s *ioim)
         }
 
         ioim->nsgpgs = nsgpgs;
-        bfa_ioim_sgpg_setup(ioim);
+        ioim->sgpg = bfa_q_first(&ioim->sgpg_q);
 
         return BFA_TRUE;
 }
 
-static void
-bfa_ioim_sgpg_setup(struct bfa_ioim_s *ioim)
-{
-        int             sgeid, nsges, i;
-        struct bfi_sge_s      *sge;
-        struct bfa_sgpg_s *sgpg;
-        u32     pgcumsz;
-        u64        addr;
-        struct scatterlist *sg;
-        struct scsi_cmnd *cmnd = (struct scsi_cmnd *) ioim->dio;
-
-        sgeid = BFI_SGE_INLINE;
-        ioim->sgpg = sgpg = bfa_q_first(&ioim->sgpg_q);
-
-        sg = scsi_sglist(cmnd);
-        sg = sg_next(sg);
-
-        do {
-                sge = sgpg->sgpg->sges;
-                nsges = ioim->nsges - sgeid;
-                if (nsges > BFI_SGPG_DATA_SGES)
-                        nsges = BFI_SGPG_DATA_SGES;
-
-                pgcumsz = 0;
-                for (i = 0; i < nsges; i++, sge++, sgeid++, sg = sg_next(sg)) {
-                        addr = bfa_os_sgaddr(sg_dma_address(sg));
-                        sge->sga = *(union bfi_addr_u *) &addr;
-                        sge->sg_len = sg_dma_len(sg);
-                        pgcumsz += sge->sg_len;
-
-                        /*
-                         * set flags
-                         */
-                        if (i < (nsges - 1))
-                                sge->flags = BFI_SGE_DATA;
-                        else if (sgeid < (ioim->nsges - 1))
-                                sge->flags = BFI_SGE_DATA_CPL;
-                        else
-                                sge->flags = BFI_SGE_DATA_LAST;
-
-                        bfa_sge_to_le(sge);
-                }
-
-                sgpg = (struct bfa_sgpg_s *) bfa_q_next(sgpg);
-
-                /*
-                 * set the link element of each page
-                 */
-                if (sgeid == ioim->nsges) {
-                        sge->flags = BFI_SGE_PGDLEN;
-                        sge->sga.a32.addr_lo = 0;
-                        sge->sga.a32.addr_hi = 0;
-                } else {
-                        sge->flags = BFI_SGE_LINK;
-                        sge->sga = sgpg->sgpg_pa;
-                }
-                sge->sg_len = pgcumsz;
-
-                bfa_sge_to_le(sge);
-        } while (sgeid < ioim->nsges);
-}
-
 /*
  * Send I/O abort request to firmware.
  */