[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 <yi.zou@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
diff --git a/include/scsi/fc_frame.h b/include/scsi/fc_frame.h
index 04d34a7..5951105 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 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 @@
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 61c746c..a70eafa 100644
--- a/include/scsi/libfc.h
+++ b/include/scsi/libfc.h
@@ -245,6 +245,7 @@
*/
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 @@
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
@@ -400,6 +410,21 @@
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
@@ -822,6 +847,11 @@
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 941818f..c41f7d0 100644
--- a/include/scsi/libfcoe.h
+++ b/include/scsi/libfcoe.h
@@ -124,24 +124,6 @@
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],