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.
Summary of changes:
1. Added ddp_setup()/ddp_done() to libfc_function_template and they are
expected to be impleted by fcoe layer
2. Added exch_send() to seperate exch_alloc() from exch_seq_send in
fc_fcp_cmd_send() since that's where we call ddp_setup() and we have to have
know the exchange xid.
3. Added calling lp->tt.ddp_setup() for read I/O if lro_enabled is set.
When ddp_setup is successful, xfer_ddp stores the corresponding exchange xid.
4. Added calling lp->tt.ddp_done() to fc_fcp_resp() to update the xfer_len
for the case of a normal complete ddp and let the LLD release ddp resource.
5. Added calling lp->tt.ddp_done() to fc_fcp_recv_data() to update the
xfer_len for the case of an incomplete ddp
6. Added calling lp->tt.ddp_done() to fc_io_compl() for an ddped I/O to make
sure ddp resource is released in case of abort
7. Also removed clearing of lro_enabled flag in fc_exch_mgr_alloc() since
that is taken care of by fcoe_sw_netdev_config() now.
Signed-off-by: Yi Zou <yi.zou@xxxxxxxxx>
---
drivers/scsi/libfc/fc_exch.c | 46 +++++++++++++++++++++++++++---------------
drivers/scsi/libfc/fc_fcp.c | 36 +++++++++++++++++++++++++++++++--
include/scsi/libfc.h | 46 ++++++++++++++++++++++++++++++++++++++++++
3 files changed, 110 insertions(+), 18 deletions(-)
diff --git a/drivers/scsi/libfc/fc_exch.c b/drivers/scsi/libfc/fc_exch.c
index 2fb2282..8faf5e8 100644
--- a/drivers/scsi/libfc/fc_exch.c
+++ b/drivers/scsi/libfc/fc_exch.c
@@ -1753,9 +1753,6 @@ struct fc_exch_mgr *fc_exch_mgr_alloc(struct fc_lport *lp,
mp->max_read = lp->lro_xid;
mp->last_read = min_xid - 1;
mp->last_xid = mp->max_read;
- } else {
- /* disable lro if no xid control over read */
- lp->lro_enabled = 0;
}
INIT_LIST_HEAD(&mp->ex_list);
@@ -1795,24 +1792,19 @@ struct fc_exch *fc_exch_get(struct fc_lport *lp, struct fc_frame *fp)
}
EXPORT_SYMBOL(fc_exch_get);
-struct fc_seq *fc_exch_seq_send(struct fc_lport *lp,
- struct fc_frame *fp,
- void (*resp)(struct fc_seq *,
- struct fc_frame *fp,
- void *arg),
- void (*destructor)(struct fc_seq *, void *),
- void *arg, u32 timer_msec)
+struct fc_seq *fc_exch_send(struct fc_lport *lp,
+ struct fc_exch *ep,
+ struct fc_frame *fp,
+ void (*resp)(struct fc_seq *,
+ struct fc_frame *fp,
+ void *arg),
+ void (*destructor)(struct fc_seq *, void *),
+ void *arg, u32 timer_msec)
{
- struct fc_exch *ep;
struct fc_seq *sp = NULL;
struct fc_frame_header *fh;
int rc = 1;
- ep = lp->tt.exch_get(lp, fp);
- if (!ep) {
- fc_frame_free(fp);
- return NULL;
- }
ep->esb_stat |= ESB_ST_SEQ_INIT;
fh = fc_frame_header_get(fp);
fc_exch_set_addr(ep, ntoh24(fh->fh_s_id), ntoh24(fh->fh_d_id));
@@ -1846,6 +1838,25 @@ err:
fc_exch_mgr_delete_ep(ep);
return NULL;
}
+EXPORT_SYMBOL(fc_exch_send);
+
+struct fc_seq *fc_exch_seq_send(struct fc_lport *lp,
+ struct fc_frame *fp,
+ void (*resp)(struct fc_seq *,
+ struct fc_frame *fp,
+ void *arg),
+ void (*destructor)(struct fc_seq *, void *),
+ void *arg, u32 timer_msec)
+{
+ struct fc_exch *ep;
+
+ ep = lp->tt.exch_get(lp, fp);
+ if (!ep) {
+ fc_frame_free(fp);
+ return NULL;
+ }
+ return fc_exch_send(lp, ep, fp, resp, destructor, arg, timer_msec);
+}
EXPORT_SYMBOL(fc_exch_seq_send);
/*
@@ -1906,6 +1917,9 @@ int fc_exch_init(struct fc_lport *lp)
if (!lp->tt.seq_start_next)
lp->tt.seq_start_next = fc_seq_start_next;
+ if (!lp->tt.exch_send)
+ lp->tt.exch_send = fc_exch_send;
+
if (!lp->tt.exch_seq_send)
lp->tt.exch_seq_send = fc_exch_seq_send;
diff --git a/drivers/scsi/libfc/fc_fcp.c b/drivers/scsi/libfc/fc_fcp.c
index 92a72c7..c6ef7fe 100644
--- a/drivers/scsi/libfc/fc_fcp.c
+++ b/drivers/scsi/libfc/fc_fcp.c
@@ -285,6 +285,11 @@ 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 */
+ if (fsp->xfer_ddp && lp->tt.ddp_done) {
+ fsp->xfer_len = lp->tt.ddp_done(lp, fsp->xfer_ddp);
+ fsp->xfer_ddp = 0;
+ }
if (offset + len > fsp->data_len) {
/* this should never happen */
if ((fr_flags(fp) & FCPHF_CRC_UNCHECKED) &&
@@ -740,6 +745,12 @@ 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 */
+ if (fsp->xfer_ddp && fsp->lp->tt.ddp_done) {
+ fsp->xfer_len = fsp->lp->tt.ddp_done(fsp->lp, fsp->xfer_ddp);
+ fsp->xfer_ddp = 0;
+ }
+
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)) {
@@ -987,6 +998,7 @@ static int fc_fcp_cmd_send(struct fc_lport *lp, struct fc_fcp_pkt *fsp,
{
struct fc_frame *fp;
struct fc_seq *seq;
+ struct fc_exch *ep;
struct fc_rport *rport;
struct fc_rport_libfc_priv *rp;
const size_t len = sizeof(fsp->cdb_cmd);
@@ -1011,7 +1023,21 @@ static int fc_fcp_cmd_send(struct fc_lport *lp, struct fc_fcp_pkt *fsp,
fc_host_port_id(rp->local_port->host), FC_TYPE_FCP,
FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
- seq = lp->tt.exch_seq_send(lp, fp, resp, fc_fcp_pkt_destroy, fsp, 0);
+ ep = lp->tt.exch_get(lp, fp);
+ if (!ep) {
+ fc_frame_free(fp);
+ goto unlock;
+ rc = -1;
+ }
+
+ if ((fsp->req_flags & FC_SRB_READ) &&
+ (lp->lro_enabled) && (lp->tt.ddp_setup)) {
+ if (lp->tt.ddp_setup(lp, ep->xid, scsi_sglist(fsp->cmd),
+ scsi_sg_count(fsp->cmd)))
+ fsp->xfer_ddp = ep->xid;
+ }
+
+ seq = lp->tt.exch_send(lp, ep, fp, resp, fc_fcp_pkt_destroy, fsp, 0);
if (!seq) {
fc_frame_free(fp);
rc = -1;
@@ -1736,6 +1762,13 @@ static void fc_io_compl(struct fc_fcp_pkt *fsp)
struct fc_lport *lp;
unsigned long flags;
+ /* release outstanding ddp context */
+ lp = fsp->lp;
+ if (fsp->xfer_ddp && lp->tt.ddp_done) {
+ lp->tt.ddp_done(lp, fsp->xfer_ddp);
+ fsp->xfer_ddp = 0;
+ }
+
fsp->state |= FC_SRB_COMPL;
if (!(fsp->state & FC_SRB_FCP_PROCESSING_TMO)) {
spin_unlock_bh(&fsp->scsi_pkt_lock);
@@ -1743,7 +1776,6 @@ static void fc_io_compl(struct fc_fcp_pkt *fsp)
spin_lock_bh(&fsp->scsi_pkt_lock);
}
- lp = fsp->lp;
si = fc_get_scsi_internal(lp);
spin_lock_irqsave(lp->host->host_lock, flags);
if (!fsp->cmd) {
diff --git a/include/scsi/libfc.h b/include/scsi/libfc.h
index a4c6050..c7fc122 100644
--- a/include/scsi/libfc.h
+++ b/include/scsi/libfc.h
@@ -274,6 +274,7 @@ 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 */
@@ -429,6 +430,37 @@ struct libfc_function_template {
void *arg, unsigned int timer_msec);
/*
+ * This does the same job like exch_seq_send() except that the caller
+ * must allocate the exchange itself and pass it to exch_send()
+ *
+ * STATUS: OPTIONAL
+ */
+ struct fc_seq *(*exch_send)(struct fc_lport *lp,
+ struct fc_exch *ep,
+ struct fc_frame *fp,
+ void (*resp)(struct fc_seq *sp,
+ struct fc_frame *fp,
+ void *arg),
+ void (*destructor)(struct fc_seq *sp,
+ 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.
*
* STATUS: OPTIONAL
@@ -917,6 +949,20 @@ struct fc_seq *fc_exch_seq_send(struct fc_lport *lp,
void (*destructor)(struct fc_seq *sp,
void *arg),
void *arg, u32 timer_msec);
+/*
+ * This function is for exch_send function pointer in
+ * struct libfc_function_template, see comment block on
+ * exch_send for description of this function.
+ */
+struct fc_seq *fc_exch_send(struct fc_lport *lp,
+ struct fc_exch *ep,
+ struct fc_frame *fp,
+ void (*resp)(struct fc_seq *sp,
+ struct fc_frame *fp,
+ void *arg),
+ void (*destructor)(struct fc_seq *sp,
+ void *arg),
+ void *arg, u32 timer_msec);
/*
* send a frame using existing sequence and exchange.
--
To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
