Commit b277d2aa authored by Yi Zou's avatar Yi Zou Committed by James Bottomley

[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: default avatarYi Zou <yi.zou@intel.com>
Signed-off-by: default avatarJames Bottomley <James.Bottomley@HansenPartnership.com>
parent 39ca9a06
......@@ -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;
......
......@@ -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);
......
......@@ -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
......
......@@ -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
*****************************/
......
......@@ -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],
......
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment