From b277d2aa9a4d969002c4157bf77b76b9ad9ca04a Mon Sep 17 00:00:00 2001 From: Yi Zou Date: Fri, 27 Feb 2009 14:07:21 -0800 Subject: [PATCH] [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 +++++++++++++++++++++++++++++++++++- include/scsi/fc_frame.h | 19 ++--------- include/scsi/libfc.h | 30 ++++++++++++++++++ include/scsi/libfcoe.h | 18 ----------- 5 files changed, 95 insertions(+), 37 deletions(-) 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); diff --git a/include/scsi/fc_frame.h b/include/scsi/fc_frame.h index 04d34a71355..59511057cee 100644 --- a/include/scsi/fc_frame.h +++ b/include/scsi/fc_frame.h @@ -54,8 +54,7 @@ #define fr_eof(fp) (fr_cb(fp)->fr_eof) #define fr_flags(fp) (fr_cb(fp)->fr_flags) #define fr_max_payload(fp) (fr_cb(fp)->fr_max_payload) -#define fr_cmd(fp) (fr_cb(fp)->fr_cmd) -#define fr_dir(fp) (fr_cmd(fp)->sc_data_direction) +#define fr_fsp(fp) (fr_cb(fp)->fr_fsp) #define fr_crc(fp) (fr_cb(fp)->fr_crc) struct fc_frame { @@ -66,7 +65,7 @@ struct fcoe_rcv_info { struct packet_type *ptype; struct fc_lport *fr_dev; /* transport layer private pointer */ struct fc_seq *fr_seq; /* for use with exchange manager */ - struct scsi_cmnd *fr_cmd; /* for use of scsi command */ + struct fc_fcp_pkt *fr_fsp; /* for the corresponding fcp I/O */ u32 fr_crc; u16 fr_max_payload; /* max FC payload */ enum fc_sof fr_sof; /* start of frame delimiter */ @@ -218,20 +217,6 @@ static inline bool fc_frame_is_cmd(const struct fc_frame *fp) return fc_frame_rctl(fp) == FC_RCTL_DD_UNSOL_CMD; } -static inline bool fc_frame_is_read(const struct fc_frame *fp) -{ - if (fc_frame_is_cmd(fp) && fr_cmd(fp)) - return fr_dir(fp) == DMA_FROM_DEVICE; - return false; -} - -static inline bool fc_frame_is_write(const struct fc_frame *fp) -{ - if (fc_frame_is_cmd(fp) && fr_cmd(fp)) - return fr_dir(fp) == DMA_TO_DEVICE; - return false; -} - /* * Check for leaks. * Print the frame header of any currently allocated frame, assuming there diff --git a/include/scsi/libfc.h b/include/scsi/libfc.h index 61c746cf55f..a70eafaad08 100644 --- a/include/scsi/libfc.h +++ b/include/scsi/libfc.h @@ -245,6 +245,7 @@ struct fc_fcp_pkt { */ struct fcp_cmnd cdb_cmd; size_t xfer_len; + u16 xfer_ddp; /* this xfer is ddped */ u32 xfer_contig_end; /* offset of end of contiguous xfer */ u16 max_payload; /* max payload size in bytes */ @@ -267,6 +268,15 @@ struct fc_fcp_pkt { u8 recov_retry; /* count of recovery retries */ struct fc_seq *recov_seq; /* sequence for REC or SRR */ }; +/* + * FC_FCP HELPER FUNCTIONS + *****************************/ +static inline bool fc_fcp_is_read(const struct fc_fcp_pkt *fsp) +{ + if (fsp && fsp->cmd) + return fsp->cmd->sc_data_direction == DMA_FROM_DEVICE; + return false; +} /* * Structure and function definitions for managing Fibre Channel Exchanges @@ -399,6 +409,21 @@ struct libfc_function_template { void *arg), void *arg, unsigned int timer_msec); + /* + * Sets up the DDP context for a given exchange id on the given + * scatterlist if LLD supports DDP for large receive. + * + * STATUS: OPTIONAL + */ + int (*ddp_setup)(struct fc_lport *lp, u16 xid, + struct scatterlist *sgl, unsigned int sgc); + /* + * Completes the DDP transfer and returns the length of data DDPed + * for the given exchange id. + * + * STATUS: OPTIONAL + */ + int (*ddp_done)(struct fc_lport *lp, u16 xid); /* * Send a frame using an existing sequence and exchange. * @@ -821,6 +846,11 @@ int fc_change_queue_type(struct scsi_device *sdev, int tag_type); */ void fc_fcp_destroy(struct fc_lport *); +/* + * Set up direct-data placement for this I/O request + */ +void fc_fcp_ddp_setup(struct fc_fcp_pkt *fsp, u16 xid); + /* * ELS/CT interface *****************************/ diff --git a/include/scsi/libfcoe.h b/include/scsi/libfcoe.h index 941818f29f5..c41f7d0c6ef 100644 --- a/include/scsi/libfcoe.h +++ b/include/scsi/libfcoe.h @@ -124,24 +124,6 @@ static inline u16 skb_fc_rxid(const struct sk_buff *skb) return be16_to_cpu(skb_fc_header(skb)->fh_rx_id); } -/* FIXME - DMA_BIDIRECTIONAL ? */ -#define skb_cb(skb) ((struct fcoe_rcv_info *)&((skb)->cb[0])) -#define skb_cmd(skb) (skb_cb(skb)->fr_cmd) -#define skb_dir(skb) (skb_cmd(skb)->sc_data_direction) -static inline bool skb_fc_is_read(const struct sk_buff *skb) -{ - if (skb_fc_is_cmd(skb) && skb_cmd(skb)) - return skb_dir(skb) == DMA_FROM_DEVICE; - return false; -} - -static inline bool skb_fc_is_write(const struct sk_buff *skb) -{ - if (skb_fc_is_cmd(skb) && skb_cmd(skb)) - return skb_dir(skb) == DMA_TO_DEVICE; - return false; -} - /* libfcoe funcs */ int fcoe_reset(struct Scsi_Host *shost); u64 fcoe_wwn_from_mac(unsigned char mac[MAX_ADDR_LEN], -- 2.41.1