From b277d2aa9a4d969002c4157bf77b76b9ad9ca04a Mon Sep 17 00:00:00 2001 From: Yi Zou Date: Fri, 27 Feb 2009 14:07:21 -0800 Subject: [SCSI] libfc: add support of large receive offload by ddp in fc_fcp When LLD supports direct data placement (ddp) for large receive of an scsi i/o coming into fc_fcp, we call into libfc_function_template's ddp_setup() to prepare for a ddp of large receive for this read I/O. When I/O is complete, we call the corresponding ddp_done() to get the length of data ddped as well as to let LLD do clean up. fc_fcp_ddp_setup()/fc_fcp_ddp_done() are added to setup and complete a ddped read I/O described by the given fc_fcp_pkt. They would call into corresponding ddp_setup/ddp_done implemented by the fcoe layer. Eventually, fcoe layer calls into LLD's ddp_setup/ddp_done provided through net_device Signed-off-by: Yi Zou Signed-off-by: James Bottomley --- drivers/scsi/libfc/fc_exch.c | 4 ++- drivers/scsi/libfc/fc_fcp.c | 61 +++++++++++++++++++++++++++++++++++++++++++- 2 files changed, 63 insertions(+), 2 deletions(-) (limited to 'drivers/scsi') diff --git a/drivers/scsi/libfc/fc_exch.c b/drivers/scsi/libfc/fc_exch.c index 8a0c5c239e9..992af05aacf 100644 --- a/drivers/scsi/libfc/fc_exch.c +++ b/drivers/scsi/libfc/fc_exch.c @@ -489,7 +489,7 @@ static u16 fc_em_alloc_xid(struct fc_exch_mgr *mp, const struct fc_frame *fp) struct fc_exch *ep = NULL; if (mp->max_read) { - if (fc_frame_is_read(fp)) { + if (fc_fcp_is_read(fr_fsp(fp))) { min = mp->min_xid; max = mp->max_read; plast = &mp->last_read; @@ -1841,6 +1841,8 @@ struct fc_seq *fc_exch_seq_send(struct fc_lport *lp, fc_exch_setup_hdr(ep, fp, ep->f_ctl); sp->cnt++; + fc_fcp_ddp_setup(fr_fsp(fp), ep->xid); + if (unlikely(lp->tt.frame_send(lp, fp))) goto err; diff --git a/drivers/scsi/libfc/fc_fcp.c b/drivers/scsi/libfc/fc_fcp.c index 48adb89d911..a5725f3b7ce 100644 --- a/drivers/scsi/libfc/fc_fcp.c +++ b/drivers/scsi/libfc/fc_fcp.c @@ -264,6 +264,56 @@ static void fc_fcp_retry_cmd(struct fc_fcp_pkt *fsp) fc_fcp_complete_locked(fsp); } +/* + * fc_fcp_ddp_setup - calls to LLD's ddp_setup to set up DDP + * transfer for a read I/O indicated by the fc_fcp_pkt. + * @fsp: ptr to the fc_fcp_pkt + * + * This is called in exch_seq_send() when we have a newly allocated + * exchange with a valid exchange id to setup ddp. + * + * returns: none + */ +void fc_fcp_ddp_setup(struct fc_fcp_pkt *fsp, u16 xid) +{ + struct fc_lport *lp; + + if (!fsp) + return; + + lp = fsp->lp; + if ((fsp->req_flags & FC_SRB_READ) && + (lp->lro_enabled) && (lp->tt.ddp_setup)) { + if (lp->tt.ddp_setup(lp, xid, scsi_sglist(fsp->cmd), + scsi_sg_count(fsp->cmd))) + fsp->xfer_ddp = xid; + } +} +EXPORT_SYMBOL(fc_fcp_ddp_setup); + +/* + * fc_fcp_ddp_done - calls to LLD's ddp_done to release any + * DDP related resources for this I/O if it is initialized + * as a ddp transfer + * @fsp: ptr to the fc_fcp_pkt + * + * returns: none + */ +static void fc_fcp_ddp_done(struct fc_fcp_pkt *fsp) +{ + struct fc_lport *lp; + + if (!fsp) + return; + + lp = fsp->lp; + if (fsp->xfer_ddp && lp->tt.ddp_done) { + fsp->xfer_len = lp->tt.ddp_done(lp, fsp->xfer_ddp); + fsp->xfer_ddp = 0; + } +} + + /* * Receive SCSI data from target. * Called after receiving solicited data. @@ -289,6 +339,9 @@ static void fc_fcp_recv_data(struct fc_fcp_pkt *fsp, struct fc_frame *fp) len = fr_len(fp) - sizeof(*fh); buf = fc_frame_payload_get(fp, 0); + /* if this I/O is ddped, update xfer len */ + fc_fcp_ddp_done(fsp); + if (offset + len > fsp->data_len) { /* this should never happen */ if ((fr_flags(fp) & FCPHF_CRC_UNCHECKED) && @@ -750,6 +803,9 @@ static void fc_fcp_resp(struct fc_fcp_pkt *fsp, struct fc_frame *fp) fsp->scsi_comp_flags = flags; expected_len = fsp->data_len; + /* if ddp, update xfer len */ + fc_fcp_ddp_done(fsp); + if (unlikely((flags & ~FCP_CONF_REQ) || fc_rp->fr_status)) { rp_ex = (void *)(fc_rp + 1); if (flags & (FCP_RSP_LEN_VAL | FCP_SNS_LEN_VAL)) { @@ -1012,7 +1068,7 @@ static int fc_fcp_cmd_send(struct fc_lport *lp, struct fc_fcp_pkt *fsp, } memcpy(fc_frame_payload_get(fp, len), &fsp->cdb_cmd, len); - fr_cmd(fp) = fsp->cmd; + fr_fsp(fp) = fsp; rport = fsp->rport; fsp->max_payload = rport->maxframe_size; rp = rport->dd_data; @@ -1746,6 +1802,9 @@ static void fc_io_compl(struct fc_fcp_pkt *fsp) struct fc_lport *lp; unsigned long flags; + /* release outstanding ddp context */ + fc_fcp_ddp_done(fsp); + fsp->state |= FC_SRB_COMPL; if (!(fsp->state & FC_SRB_FCP_PROCESSING_TMO)) { spin_unlock_bh(&fsp->scsi_pkt_lock); -- cgit v1.2.3-70-g09d2