[PATCH v4 25/50] scsi: imm: Move the SCSI pointer to private command data

Bart Van Assche
2022-02-16T21:04:00Z

Set .cmd_size in the SCSI host template instead of using the SCSI pointer.
This patch prepares for removal of the SCSI pointer from struct scsi_cmnd.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
---
drivers/scsi/imm.c | 88 ++++++++++++++++++++++++----------------------
drivers/scsi/imm.h | 5 +++
2 files changed, 50 insertions(+), 43 deletions(-)

diff --git a/drivers/scsi/imm.c b/drivers/scsi/imm.c
index 8afdb4dba2be..7a499d621c25 100644
--- a/drivers/scsi/imm.c
+++ b/drivers/scsi/imm.c
@@ -66,7 +66,7 @@ static void got_it(imm_struct *dev)
{
dev->base = dev->dev->port->base;
if (dev->cur_cmd)
- dev->cur_cmd->SCp.phase = 1;
+ imm_scsi_pointer(dev->cur_cmd)->phase = 1;
else
wake_up(dev->waiting);
}
@@ -618,13 +618,14 @@ static inline int imm_send_command(struct scsi_cmnd *cmd)
* The driver appears to remain stable if we speed up the parallel port
* i/o in this function, but not elsewhere.
*/
-static int imm_completion(struct scsi_cmnd *cmd)
+static int imm_completion(struct scsi_cmnd *const cmd)
{
/* Return codes:
* -1 Error
* 0 Told to schedule
* 1 Finished data transfer
*/
+ struct scsi_pointer *scsi_pointer = imm_scsi_pointer(cmd);
imm_struct *dev = imm_dev(cmd->device->host);
unsigned short ppb = dev->base;
unsigned long start_jiffies = jiffies;
@@ -660,44 +661,43 @@ static int imm_completion(struct scsi_cmnd *cmd)
* a) Drive status is screwy (!ready && !present)
* b) Drive is requesting/sending more data than expected
*/
- if (((r & 0x88) != 0x88) || (cmd->SCp.this_residual <= 0)) {
+ if ((r & 0x88) != 0x88 || scsi_pointer->this_residual <= 0) {
imm_fail(dev, DID_ERROR);
return -1; /* ERROR_RETURN */
}
/* determine if we should use burst I/O */
if (dev->rd == 0) {
- fast = (bulk
- && (cmd->SCp.this_residual >=
- IMM_BURST_SIZE)) ? IMM_BURST_SIZE : 2;
- status = imm_out(dev, cmd->SCp.ptr, fast);
+ fast = bulk && scsi_pointer->this_residual >=
+ IMM_BURST_SIZE ? IMM_BURST_SIZE : 2;
+ status = imm_out(dev, scsi_pointer->ptr, fast);
} else {
- fast = (bulk
- && (cmd->SCp.this_residual >=
- IMM_BURST_SIZE)) ? IMM_BURST_SIZE : 1;
- status = imm_in(dev, cmd->SCp.ptr, fast);
+ fast = bulk && scsi_pointer->this_residual >=
+ IMM_BURST_SIZE ? IMM_BURST_SIZE : 1;
+ status = imm_in(dev, scsi_pointer->ptr, fast);
}

- cmd->SCp.ptr += fast;
- cmd->SCp.this_residual -= fast;
+ scsi_pointer->ptr += fast;
+ scsi_pointer->this_residual -= fast;

if (!status) {
imm_fail(dev, DID_BUS_BUSY);
return -1; /* ERROR_RETURN */
}
- if (cmd->SCp.buffer && !cmd->SCp.this_residual) {
+ if (scsi_pointer->buffer && !scsi_pointer->this_residual) {
/* if scatter/gather, advance to the next segment */
- if (cmd->SCp.buffers_residual--) {
- cmd->SCp.buffer = sg_next(cmd->SCp.buffer);
- cmd->SCp.this_residual =
- cmd->SCp.buffer->length;
- cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
+ if (scsi_pointer->buffers_residual--) {
+ scsi_pointer->buffer =
+ sg_next(scsi_pointer->buffer);
+ scsi_pointer->this_residual =
+ scsi_pointer->buffer->length;
+ scsi_pointer->ptr = sg_virt(scsi_pointer->buffer);

/*
* Make sure that we transfer even number of bytes
* otherwise it makes imm_byte_out() messy.
*/
- if (cmd->SCp.this_residual & 0x01)
- cmd->SCp.this_residual++;
+ if (scsi_pointer->this_residual & 0x01)
+ scsi_pointer->this_residual++;
}
}
/* Now check to see if the drive is ready to comunicate */
@@ -762,7 +762,7 @@ static void imm_interrupt(struct work_struct *work)
}
#endif

- if (cmd->SCp.phase > 1)
+ if (imm_scsi_pointer(cmd)->phase > 1)
imm_disconnect(dev);

imm_pb_dismiss(dev);
@@ -774,8 +774,9 @@ static void imm_interrupt(struct work_struct *work)
return;
}

-static int imm_engine(imm_struct *dev, struct scsi_cmnd *cmd)
+static int imm_engine(imm_struct *dev, struct scsi_cmnd *const cmd)
{
+ struct scsi_pointer *scsi_pointer = imm_scsi_pointer(cmd);
unsigned short ppb = dev->base;
unsigned char l = 0, h = 0;
int retv, x;
@@ -786,7 +787,7 @@ static int imm_engine(imm_struct *dev, struct scsi_cmnd *cmd)
if (dev->failed)
return 0;

- switch (cmd->SCp.phase) {
+ switch (scsi_pointer->phase) {
case 0: /* Phase 0 - Waiting for parport */
if (time_after(jiffies, dev->jstart + HZ)) {
/*
@@ -800,7 +801,7 @@ static int imm_engine(imm_struct *dev, struct scsi_cmnd *cmd)

case 1: /* Phase 1 - Connected */
imm_connect(dev, CONNECT_EPP_MAYBE);
- cmd->SCp.phase++;
+ scsi_pointer->phase++;
fallthrough;

case 2: /* Phase 2 - We are now talking to the scsi bus */
@@ -808,7 +809,7 @@ static int imm_engine(imm_struct *dev, struct scsi_cmnd *cmd)
imm_fail(dev, DID_NO_CONNECT);
return 0;
}
- cmd->SCp.phase++;
+ scsi_pointer->phase++;
fallthrough;

case 3: /* Phase 3 - Ready to accept a command */
@@ -818,23 +819,23 @@ static int imm_engine(imm_struct *dev, struct scsi_cmnd *cmd)

if (!imm_send_command(cmd))
return 0;
- cmd->SCp.phase++;
+ scsi_pointer->phase++;
fallthrough;

case 4: /* Phase 4 - Setup scatter/gather buffers */
if (scsi_bufflen(cmd)) {
- cmd->SCp.buffer = scsi_sglist(cmd);
- cmd->SCp.this_residual = cmd->SCp.buffer->length;
- cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
+ scsi_pointer->buffer = scsi_sglist(cmd);
+ scsi_pointer->this_residual = scsi_pointer->buffer->length;
+ scsi_pointer->ptr = sg_virt(scsi_pointer->buffer);
} else {
- cmd->SCp.buffer = NULL;
- cmd->SCp.this_residual = 0;
- cmd->SCp.ptr = NULL;
+ scsi_pointer->buffer = NULL;
+ scsi_pointer->this_residual = 0;
+ scsi_pointer->ptr = NULL;
}
- cmd->SCp.buffers_residual = scsi_sg_count(cmd) - 1;
- cmd->SCp.phase++;
- if (cmd->SCp.this_residual & 0x01)
- cmd->SCp.this_residual++;
+ scsi_pointer->buffers_residual = scsi_sg_count(cmd) - 1;
+ scsi_pointer->phase++;
+ if (scsi_pointer->this_residual & 0x01)
+ scsi_pointer->this_residual++;
fallthrough;

case 5: /* Phase 5 - Pre-Data transfer stage */
@@ -851,7 +852,7 @@ static int imm_engine(imm_struct *dev, struct scsi_cmnd *cmd)
if ((dev->dp) && (dev->rd))
if (imm_negotiate(dev))
return 0;
- cmd->SCp.phase++;
+ scsi_pointer->phase++;
fallthrough;

case 6: /* Phase 6 - Data transfer stage */
@@ -867,7 +868,7 @@ static int imm_engine(imm_struct *dev, struct scsi_cmnd *cmd)
if (retv == 0)
return 1;
}
- cmd->SCp.phase++;
+ scsi_pointer->phase++;
fallthrough;

case 7: /* Phase 7 - Post data transfer stage */
@@ -879,7 +880,7 @@ static int imm_engine(imm_struct *dev, struct scsi_cmnd *cmd)
w_ctr(ppb, 0x4);
}
}
- cmd->SCp.phase++;
+ scsi_pointer->phase++;
fallthrough;

case 8: /* Phase 8 - Read status/message */
@@ -922,7 +923,7 @@ static int imm_queuecommand_lck(struct scsi_cmnd *cmd)
dev->jstart = jiffies;
dev->cur_cmd = cmd;
cmd->result = DID_ERROR << 16; /* default return code */
- cmd->SCp.phase = 0; /* bus free */
+ imm_scsi_pointer(cmd)->phase = 0; /* bus free */

schedule_delayed_work(&dev->imm_tq, 0);

@@ -961,7 +962,7 @@ static int imm_abort(struct scsi_cmnd *cmd)
* have tied the SCSI_MESSAGE line high in the interface
*/

- switch (cmd->SCp.phase) {
+ switch (imm_scsi_pointer(cmd)->phase) {
case 0: /* Do not have access to parport */
case 1: /* Have not connected to interface */
dev->cur_cmd = NULL; /* Forget the problem */
@@ -987,7 +988,7 @@ static int imm_reset(struct scsi_cmnd *cmd)
{
imm_struct *dev = imm_dev(cmd->device->host);

- if (cmd->SCp.phase)
+ if (imm_scsi_pointer(cmd)->phase)
imm_disconnect(dev);
dev->cur_cmd = NULL; /* Forget the problem */

@@ -1109,6 +1110,7 @@ static struct scsi_host_template imm_template = {
.sg_tablesize = SG_ALL,
.can_queue = 1,
.slave_alloc = imm_adjust_queue,
+ .cmd_size = sizeof(struct scsi_pointer),
};

/***************************************************************************
diff --git a/drivers/scsi/imm.h b/drivers/scsi/imm.h
index 7f2bb35b1b87..411cf94af5b0 100644
--- a/drivers/scsi/imm.h
+++ b/drivers/scsi/imm.h
@@ -139,6 +139,11 @@ static char *IMM_MODE_STRING[] =
#define w_ctr(x,y) outb(y, (x)+2)
#endif

+static inline struct scsi_pointer *imm_scsi_pointer(struct scsi_cmnd *cmd)
+{
+ return scsi_cmd_priv(cmd);
+}
+
static int imm_engine(imm_struct *, struct scsi_cmnd *);

#endif /* _IMM_H */