[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>
This commit is contained in:
Yi Zou
2009-02-27 14:07:21 -08:00
committed by James Bottomley
parent 39ca9a065a
commit b277d2aa9a
5 changed files with 95 additions and 37 deletions

View File

@@ -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

View File

@@ -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
*****************************/

View File

@@ -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],