[PATCH v3 39/48] scsi: ppa: Move the SCSI pointer to private command data

Bart Van Assche
2022-02-11T22:34:42Z

Set .cmd_size in the SCSI host template instead of using the SCSI pointer
from struct scsi_cmnd. 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/ppa.c | 75 ++++++++++++++++++++++++++--------------------
1 file changed, 43 insertions(+), 32 deletions(-)

diff --git a/drivers/scsi/ppa.c b/drivers/scsi/ppa.c
index 003043de23a5..00a68037e0e4 100644
--- a/drivers/scsi/ppa.c
+++ b/drivers/scsi/ppa.c
@@ -45,6 +45,11 @@ typedef struct {

#include "ppa.h"

+static struct scsi_pointer *ppa_scsi_pointer(struct scsi_cmnd *cmd)
+{
+ return scsi_cmd_priv(cmd);
+}
+
static inline ppa_struct *ppa_dev(struct Scsi_Host *host)
{
return *(ppa_struct **)&host->hostdata;
@@ -56,7 +61,7 @@ static void got_it(ppa_struct *dev)
{
dev->base = dev->dev->port->base;
if (dev->cur_cmd)
- dev->cur_cmd->SCp.phase = 1;
+ ppa_scsi_pointer(dev->cur_cmd)->phase = 1;
else
wake_up(dev->waiting);
}
@@ -511,13 +516,14 @@ static inline int ppa_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 ppa_completion(struct scsi_cmnd *cmd)
+static int ppa_completion(struct scsi_cmnd *const cmd)
{
/* Return codes:
* -1 Error
* 0 Told to schedule
* 1 Finished data transfer
*/
+ struct scsi_pointer *scsi_pointer = ppa_scsi_pointer(cmd);
ppa_struct *dev = ppa_dev(cmd->device->host);
unsigned short ppb = dev->base;
unsigned long start_jiffies = jiffies;
@@ -543,7 +549,7 @@ static int ppa_completion(struct scsi_cmnd *cmd)
if (time_after(jiffies, start_jiffies + 1))
return 0;

- if ((cmd->SCp.this_residual <= 0)) {
+ if (scsi_pointer->this_residual <= 0) {
ppa_fail(dev, DID_ERROR);
return -1; /* ERROR_RETURN */
}
@@ -572,28 +578,30 @@ static int ppa_completion(struct scsi_cmnd *cmd)
}

/* determine if we should use burst I/O */
- fast = (bulk && (cmd->SCp.this_residual >= PPA_BURST_SIZE))
- ? PPA_BURST_SIZE : 1;
+ fast = bulk && scsi_pointer->this_residual >= PPA_BURST_SIZE ?
+ PPA_BURST_SIZE : 1;

if (r == (unsigned char) 0xc0)
- status = ppa_out(dev, cmd->SCp.ptr, fast);
+ status = ppa_out(dev, scsi_pointer->ptr, fast);
else
- status = ppa_in(dev, cmd->SCp.ptr, fast);
+ status = ppa_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) {
ppa_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);
}
}
/* Now check to see if the drive is ready to comunicate */
@@ -658,7 +666,7 @@ static void ppa_interrupt(struct work_struct *work)
}
#endif

- if (cmd->SCp.phase > 1)
+ if (ppa_scsi_pointer(cmd)->phase > 1)
ppa_disconnect(dev);

ppa_pb_dismiss(dev);
@@ -670,6 +678,7 @@ static void ppa_interrupt(struct work_struct *work)

static int ppa_engine(ppa_struct *dev, struct scsi_cmnd *cmd)
{
+ struct scsi_pointer *scsi_pointer = ppa_scsi_pointer(cmd);
unsigned short ppb = dev->base;
unsigned char l = 0, h = 0;
int retv;
@@ -680,7 +689,7 @@ static int ppa_engine(ppa_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)) {
/*
@@ -715,7 +724,7 @@ static int ppa_engine(ppa_struct *dev, struct scsi_cmnd *cmd)
return 1; /* Try again in a jiffy */
}
}
- cmd->SCp.phase++;
+ scsi_pointer->phase++;
}
fallthrough;

@@ -724,7 +733,7 @@ static int ppa_engine(ppa_struct *dev, struct scsi_cmnd *cmd)
ppa_fail(dev, DID_NO_CONNECT);
return 0;
}
- cmd->SCp.phase++;
+ scsi_pointer->phase++;
fallthrough;

case 3: /* Phase 3 - Ready to accept a command */
@@ -734,21 +743,22 @@ static int ppa_engine(ppa_struct *dev, struct scsi_cmnd *cmd)

if (!ppa_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++;
+ scsi_pointer->buffers_residual = scsi_sg_count(cmd) - 1;
+ scsi_pointer->phase++;
fallthrough;

case 5: /* Phase 5 - Data transfer stage */
@@ -761,7 +771,7 @@ static int ppa_engine(ppa_struct *dev, struct scsi_cmnd *cmd)
return 0;
if (retv == 0)
return 1;
- cmd->SCp.phase++;
+ scsi_pointer->phase++;
fallthrough;

case 6: /* Phase 6 - Read status/message */
@@ -798,7 +808,7 @@ static int ppa_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 */
+ ppa_scsi_pointer(cmd)->phase = 0; /* bus free */

schedule_delayed_work(&dev->ppa_tq, 0);

@@ -839,7 +849,7 @@ static int ppa_abort(struct scsi_cmnd *cmd)
* have tied the SCSI_MESSAGE line high in the interface
*/

- switch (cmd->SCp.phase) {
+ switch (ppa_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 */
@@ -861,7 +871,7 @@ static int ppa_reset(struct scsi_cmnd *cmd)
{
ppa_struct *dev = ppa_dev(cmd->device->host);

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

@@ -976,6 +986,7 @@ static struct scsi_host_template ppa_template = {
.sg_tablesize = SG_ALL,
.can_queue = 1,
.slave_alloc = ppa_adjust_queue,
+ .cmd_size = sizeof(struct scsi_pointer),
};

/***************************************************************************