[PATCH v4 28/50] scsi: libfc: Stop using the SCSI pointer

Bart Van Assche
2022-02-16T21:04:06Z

Move the fc_fcp_pkt pointer, the residual length and the SCSI status into
the new data structure libfc_cmd_priv. This patch prepares for removal of
the SCSI pointer from struct scsi_cmnd.

The user of the libfc data path functions have been identified as follows:
$ git grep -lw fc_queuecommand | grep -v scsi/libfc/
drivers/scsi/fcoe/fcoe.c

Cc: Hannes Reinecke <hare@suse.de>
Cc: Saurav Kashyap <skashyap@marvell.com>
Cc: Javed Hasan <jhasan@marvell.com>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
---
drivers/scsi/fcoe/fcoe.c | 1 +
drivers/scsi/libfc/fc_fcp.c | 26 +++++++++++---------------
include/scsi/libfc.h | 9 +++++++++
3 files changed, 21 insertions(+), 15 deletions(-)

diff --git a/drivers/scsi/fcoe/fcoe.c b/drivers/scsi/fcoe/fcoe.c
index 6415f88738ad..44ca6110213c 100644
--- a/drivers/scsi/fcoe/fcoe.c
+++ b/drivers/scsi/fcoe/fcoe.c
@@ -277,6 +277,7 @@ static struct scsi_host_template fcoe_shost_template = {
.sg_tablesize = SG_ALL,
.max_sectors = 0xffff,
.track_queue_depth = 1,
+ .cmd_size = sizeof(struct libfc_cmd_priv),
};

/**
diff --git a/drivers/scsi/libfc/fc_fcp.c b/drivers/scsi/libfc/fc_fcp.c
index 871b11edb586..bce90eb56c9c 100644
--- a/drivers/scsi/libfc/fc_fcp.c
+++ b/drivers/scsi/libfc/fc_fcp.c
@@ -45,14 +45,10 @@ static struct kmem_cache *scsi_pkt_cachep;
#define FC_SRB_READ (1 << 1)
#define FC_SRB_WRITE (1 << 0)

-/*
- * The SCp.ptr should be tested and set under the scsi_pkt_queue lock
- */
-#define CMD_SP(Cmnd) ((struct fc_fcp_pkt *)(Cmnd)->SCp.ptr)
-#define CMD_ENTRY_STATUS(Cmnd) ((Cmnd)->SCp.have_data_in)
-#define CMD_COMPL_STATUS(Cmnd) ((Cmnd)->SCp.this_residual)
-#define CMD_SCSI_STATUS(Cmnd) ((Cmnd)->SCp.Status)
-#define CMD_RESID_LEN(Cmnd) ((Cmnd)->SCp.buffers_residual)
+static struct libfc_cmd_priv *libfc_priv(struct scsi_cmnd *cmd)
+{
+ return scsi_cmd_priv(cmd);
+}

/**
* struct fc_fcp_internal - FCP layer internal data
@@ -1137,7 +1133,7 @@ static int fc_fcp_pkt_send(struct fc_lport *lport, struct fc_fcp_pkt *fsp)
unsigned long flags;
int rc;

- fsp->cmd->SCp.ptr = (char *)fsp;
+ libfc_priv(fsp->cmd)->fsp = fsp;
fsp->cdb_cmd.fc_dl = htonl(fsp->data_len);
fsp->cdb_cmd.fc_flags = fsp->req_flags & ~FCP_CFL_LEN_MASK;

@@ -1150,7 +1146,7 @@ static int fc_fcp_pkt_send(struct fc_lport *lport, struct fc_fcp_pkt *fsp)
rc = lport->tt.fcp_cmd_send(lport, fsp, fc_fcp_recv);
if (unlikely(rc)) {
spin_lock_irqsave(&si->scsi_queue_lock, flags);
- fsp->cmd->SCp.ptr = NULL;
+ libfc_priv(fsp->cmd)->fsp = NULL;
list_del(&fsp->list);
spin_unlock_irqrestore(&si->scsi_queue_lock, flags);
}
@@ -1983,7 +1979,7 @@ static void fc_io_compl(struct fc_fcp_pkt *fsp)
fc_fcp_can_queue_ramp_up(lport);

sc_cmd = fsp->cmd;
- CMD_SCSI_STATUS(sc_cmd) = fsp->cdb_status;
+ libfc_priv(sc_cmd)->status = fsp->cdb_status;
switch (fsp->status_code) {
case FC_COMPLETE:
if (fsp->cdb_status == 0) {
@@ -1992,7 +1988,7 @@ static void fc_io_compl(struct fc_fcp_pkt *fsp)
*/
sc_cmd->result = DID_OK << 16;
if (fsp->scsi_resid)
- CMD_RESID_LEN(sc_cmd) = fsp->scsi_resid;
+ libfc_priv(sc_cmd)->resid_len = fsp->scsi_resid;
} else {
/*
* transport level I/O was ok but scsi
@@ -2025,7 +2021,7 @@ static void fc_io_compl(struct fc_fcp_pkt *fsp)
*/
FC_FCP_DBG(fsp, "Returning DID_ERROR to scsi-ml "
"due to FC_DATA_UNDRUN (scsi)\n");
- CMD_RESID_LEN(sc_cmd) = fsp->scsi_resid;
+ libfc_priv(sc_cmd)->resid_len = fsp->scsi_resid;
sc_cmd->result = (DID_ERROR << 16) | fsp->cdb_status;
}
break;
@@ -2085,7 +2081,7 @@ static void fc_io_compl(struct fc_fcp_pkt *fsp)

spin_lock_irqsave(&si->scsi_queue_lock, flags);
list_del(&fsp->list);
- sc_cmd->SCp.ptr = NULL;
+ libfc_priv(sc_cmd)->fsp = NULL;
spin_unlock_irqrestore(&si->scsi_queue_lock, flags);
scsi_done(sc_cmd);

@@ -2121,7 +2117,7 @@ int fc_eh_abort(struct scsi_cmnd *sc_cmd)

si = fc_get_scsi_internal(lport);
spin_lock_irqsave(&si->scsi_queue_lock, flags);
- fsp = CMD_SP(sc_cmd);
+ fsp = libfc_priv(sc_cmd)->fsp;
if (!fsp) {
/* command completed while scsi eh was setting up */
spin_unlock_irqrestore(&si->scsi_queue_lock, flags);
diff --git a/include/scsi/libfc.h b/include/scsi/libfc.h
index eeb8d689ff6b..6e29e1719db1 100644
--- a/include/scsi/libfc.h
+++ b/include/scsi/libfc.h
@@ -351,6 +351,15 @@ struct fc_fcp_pkt {
struct completion tm_done;
} ____cacheline_aligned_in_smp;

+/*
+ * @fsp should be tested and set under the scsi_pkt_queue lock
+ */
+struct libfc_cmd_priv {
+ struct fc_fcp_pkt *fsp;
+ u32 resid_len;
+ u8 status;
+};
+
/*
* Structure and function definitions for managing Fibre Channel Exchanges
* and Sequences