[PATCH v3 11/48] scsi: arm: Move the SCSI pointer to private command data

Bart Van Assche
2022-02-11T22:33:35Z

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. The ARM SCSI drivers have been identified as follows:
$ git grep -l '#include.*arm_scsi.h'
drivers/scsi/arm/acornscsi.c
drivers/scsi/arm/cumana_2.c
drivers/scsi/arm/eesox.c
drivers/scsi/arm/fas216.c
drivers/scsi/arm/powertec.c

Cc: Russell King <linux@armlinux.org.uk>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
---
drivers/scsi/arm/acornscsi.c | 20 ++++++++++++--------
drivers/scsi/arm/arm_scsi.h | 33 +++++++++++++++++++++++----------
drivers/scsi/arm/fas216.c | 28 +++++++++++++++++-----------
drivers/scsi/arm/fas216.h | 4 ++++
4 files changed, 56 insertions(+), 29 deletions(-)

diff --git a/drivers/scsi/arm/acornscsi.c b/drivers/scsi/arm/acornscsi.c
index 38aa9333631b..7602639da9b3 100644
--- a/drivers/scsi/arm/acornscsi.c
+++ b/drivers/scsi/arm/acornscsi.c
@@ -729,7 +729,7 @@ intr_ret_t acornscsi_kick(AS_Host *host)
*/
host->scsi.phase = PHASE_CONNECTING;
host->SCpnt = SCpnt;
- host->scsi.SCp = SCpnt->SCp;
+ host->scsi.SCp = *arm_scsi_pointer(SCpnt);
host->dma.xfer_setup = 0;
host->dma.xfer_required = 0;
host->dma.xfer_done = 0;
@@ -1424,6 +1424,7 @@ unsigned char acornscsi_readmessagebyte(AS_Host *host)
static
void acornscsi_message(AS_Host *host)
{
+ struct scsi_pointer *scsi_pointer;
unsigned char message[16];
unsigned int msgidx = 0, msglen = 1;

@@ -1493,8 +1494,9 @@ void acornscsi_message(AS_Host *host)
* the saved data pointer for the current I/O process.
*/
acornscsi_dma_cleanup(host);
- host->SCpnt->SCp = host->scsi.SCp;
- host->SCpnt->SCp.sent_command = 0;
+ scsi_pointer = arm_scsi_pointer(host->SCpnt);
+ *scsi_pointer = host->scsi.SCp;
+ scsi_pointer->sent_command = 0;
host->scsi.phase = PHASE_MSGIN;
break;

@@ -1509,7 +1511,7 @@ void acornscsi_message(AS_Host *host)
* the present command and status areas.'
*/
acornscsi_dma_cleanup(host);
- host->scsi.SCp = host->SCpnt->SCp;
+ host->scsi.SCp = *arm_scsi_pointer(host->SCpnt);
host->scsi.phase = PHASE_MSGIN;
break;

@@ -1809,7 +1811,7 @@ int acornscsi_reconnect_finish(AS_Host *host)
/*
* Restore data pointer from SAVED pointers.
*/
- host->scsi.SCp = host->SCpnt->SCp;
+ host->scsi.SCp = *arm_scsi_pointer(host->SCpnt);
#if (DEBUG & (DEBUG_QUEUES|DEBUG_DISCON))
printk(", data pointers: [%p, %X]",
host->scsi.SCp.ptr, host->scsi.SCp.this_residual);
@@ -2408,6 +2410,7 @@ acornscsi_intr(int irq, void *dev_id)
*/
static int acornscsi_queuecmd_lck(struct scsi_cmnd *SCpnt)
{
+ struct scsi_pointer *scsi_pointer = arm_scsi_pointer(SCpnt);
void (*done)(struct scsi_cmnd *) = scsi_done;
AS_Host *host = (AS_Host *)SCpnt->device->host->hostdata;

@@ -2423,9 +2426,9 @@ static int acornscsi_queuecmd_lck(struct scsi_cmnd *SCpnt)

SCpnt->host_scribble = NULL;
SCpnt->result = 0;
- SCpnt->SCp.phase = (int)acornscsi_datadirection(SCpnt->cmnd[0]);
- SCpnt->SCp.sent_command = 0;
- SCpnt->SCp.scsi_xferred = 0;
+ scsi_pointer->phase = (int)acornscsi_datadirection(SCpnt->cmnd[0]);
+ scsi_pointer->sent_command = 0;
+ scsi_pointer->scsi_xferred = 0;

init_SCp(SCpnt);

@@ -2791,6 +2794,7 @@ static struct scsi_host_template acornscsi_template = {
.cmd_per_lun = 2,
.dma_boundary = PAGE_SIZE - 1,
.proc_name = "acornscsi",
+ .cmd_size = sizeof(struct arm_cmd_priv),
};

static int acornscsi_probe(struct expansion_card *ec, const struct ecard_id *id)
diff --git a/drivers/scsi/arm/arm_scsi.h b/drivers/scsi/arm/arm_scsi.h
index 3eb5c6aa93c9..ea9fcd92c6de 100644
--- a/drivers/scsi/arm/arm_scsi.h
+++ b/drivers/scsi/arm/arm_scsi.h
@@ -9,6 +9,17 @@

#define BELT_AND_BRACES

+struct arm_cmd_priv {
+ struct scsi_pointer scsi_pointer;
+};
+
+static inline struct scsi_pointer *arm_scsi_pointer(struct scsi_cmnd *cmd)
+{
+ struct arm_cmd_priv *acmd = scsi_cmd_priv(cmd);
+
+ return &acmd->scsi_pointer;
+}
+
/*
* The scatter-gather list handling. This contains all
* the yucky stuff that needs to be fixed properly.
@@ -76,16 +87,18 @@ static inline void put_next_SCp_byte(struct scsi_pointer *SCp, unsigned char c)

static inline void init_SCp(struct scsi_cmnd *SCpnt)
{
- memset(&SCpnt->SCp, 0, sizeof(struct scsi_pointer));
+ struct scsi_pointer *scsi_pointer = arm_scsi_pointer(SCpnt);
+
+ memset(scsi_pointer, 0, sizeof(struct scsi_pointer));

if (scsi_bufflen(SCpnt)) {
unsigned long len = 0;

- SCpnt->SCp.buffer = scsi_sglist(SCpnt);
- SCpnt->SCp.buffers_residual = scsi_sg_count(SCpnt) - 1;
- SCpnt->SCp.ptr = sg_virt(SCpnt->SCp.buffer);
- SCpnt->SCp.this_residual = SCpnt->SCp.buffer->length;
- SCpnt->SCp.phase = scsi_bufflen(SCpnt);
+ scsi_pointer->buffer = scsi_sglist(SCpnt);
+ scsi_pointer->buffers_residual = scsi_sg_count(SCpnt) - 1;
+ scsi_pointer->ptr = sg_virt(scsi_pointer->buffer);
+ scsi_pointer->this_residual = scsi_pointer->buffer->length;
+ scsi_pointer->phase = scsi_bufflen(SCpnt);

#ifdef BELT_AND_BRACES
{ /*
@@ -109,15 +122,15 @@ static inline void init_SCp(struct scsi_cmnd *SCpnt)
* FIXME: Totaly naive fixup. We should abort
* with error
*/
- SCpnt->SCp.phase =
+ scsi_pointer->phase =
min_t(unsigned long, len,
scsi_bufflen(SCpnt));
}
}
#endif
} else {
- SCpnt->SCp.ptr = NULL;
- SCpnt->SCp.this_residual = 0;
- SCpnt->SCp.phase = 0;
+ scsi_pointer->ptr = NULL;
+ scsi_pointer->this_residual = 0;
+ scsi_pointer->phase = 0;
}
}
diff --git a/drivers/scsi/arm/fas216.c b/drivers/scsi/arm/fas216.c
index a23e34c9f7de..4ce0b2d73614 100644
--- a/drivers/scsi/arm/fas216.c
+++ b/drivers/scsi/arm/fas216.c
@@ -761,7 +761,7 @@ static void fas216_transfer(FAS216_Info *info)
fas216_log(info, LOG_ERROR, "null buffer passed to "
"fas216_starttransfer");
print_SCp(&info->scsi.SCp, "SCp: ", "\n");
- print_SCp(&info->SCpnt->SCp, "Cmnd SCp: ", "\n");
+ print_SCp(arm_scsi_pointer(info->SCpnt), "Cmnd SCp: ", "\n");
return;
}

@@ -1011,7 +1011,7 @@ fas216_reselected_intr(FAS216_Info *info)
/*
* Restore data pointer from SAVED data pointer
*/
- info->scsi.SCp = info->SCpnt->SCp;
+ info->scsi.SCp = *arm_scsi_pointer(info->SCpnt);

fas216_log(info, LOG_CONNECT, "data pointers: [%p, %X]",
info->scsi.SCp.ptr, info->scsi.SCp.this_residual);
@@ -1054,6 +1054,7 @@ fas216_reselected_intr(FAS216_Info *info)

static void fas216_parse_message(FAS216_Info *info, unsigned char *message, int msglen)
{
+ struct scsi_pointer *scsi_pointer;
int i;

switch (message[0]) {
@@ -1078,8 +1079,9 @@ static void fas216_parse_message(FAS216_Info *info, unsigned char *message, int
* as required by the SCSI II standard. These always
* point to the start of their respective areas.
*/
- info->SCpnt->SCp = info->scsi.SCp;
- info->SCpnt->SCp.sent_command = 0;
+ scsi_pointer = arm_scsi_pointer(info->SCpnt);
+ *scsi_pointer = info->scsi.SCp;
+ scsi_pointer->sent_command = 0;
fas216_log(info, LOG_CONNECT | LOG_MESSAGES | LOG_BUFFER,
"save data pointers: [%p, %X]",
info->scsi.SCp.ptr, info->scsi.SCp.this_residual);
@@ -1092,7 +1094,7 @@ static void fas216_parse_message(FAS216_Info *info, unsigned char *message, int
/*
* Restore current data pointer from SAVED data pointer
*/
- info->scsi.SCp = info->SCpnt->SCp;
+ info->scsi.SCp = *arm_scsi_pointer(info->SCpnt);
fas216_log(info, LOG_CONNECT | LOG_MESSAGES | LOG_BUFFER,
"restore data pointers: [%p, 0x%x]",
info->scsi.SCp.ptr, info->scsi.SCp.this_residual);
@@ -1770,7 +1772,7 @@ static void fas216_start_command(FAS216_Info *info, struct scsi_cmnd *SCpnt)
* claim host busy
*/
info->scsi.phase = PHASE_SELECTION;
- info->scsi.SCp = SCpnt->SCp;
+ info->scsi.SCp = *arm_scsi_pointer(SCpnt);
info->SCpnt = SCpnt;
info->dma.transfer_type = fasdma_none;

@@ -1849,7 +1851,7 @@ static void fas216_do_bus_device_reset(FAS216_Info *info,
* claim host busy
*/
info->scsi.phase = PHASE_SELECTION;
- info->scsi.SCp = SCpnt->SCp;
+ info->scsi.SCp = *arm_scsi_pointer(SCpnt);
info->SCpnt = SCpnt;
info->dma.transfer_type = fasdma_none;

@@ -1999,11 +2001,13 @@ static void fas216_devicereset_done(FAS216_Info *info, struct scsi_cmnd *SCpnt,
static void fas216_rq_sns_done(FAS216_Info *info, struct scsi_cmnd *SCpnt,
unsigned int result)
{
+ struct scsi_pointer *scsi_pointer = arm_scsi_pointer(SCpnt);
+
fas216_log_target(info, LOG_CONNECT, SCpnt->device->id,
"request sense complete, result=0x%04x%02x%02x",
- result, SCpnt->SCp.Message, SCpnt->SCp.Status);
+ result, scsi_pointer->Message, scsi_pointer->Status);

- if (result != DID_OK || SCpnt->SCp.Status != SAM_STAT_GOOD)
+ if (result != DID_OK || scsi_pointer->Status != SAM_STAT_GOOD)
/*
* Something went wrong. Make sure that we don't
* have valid data in the sense buffer that could
@@ -2033,6 +2037,8 @@ static void fas216_rq_sns_done(FAS216_Info *info, struct scsi_cmnd *SCpnt,
static void
fas216_std_done(FAS216_Info *info, struct scsi_cmnd *SCpnt, unsigned int result)
{
+ struct scsi_pointer *scsi_pointer = arm_scsi_pointer(SCpnt);
+
info->stats.fins += 1;

set_host_byte(SCpnt, result);
@@ -2107,8 +2113,8 @@ fas216_std_done(FAS216_Info *info, struct scsi_cmnd *SCpnt, unsigned int result)
fas216_log_target(info, LOG_CONNECT, SCpnt->device->id,
"requesting sense");
init_SCp(SCpnt);
- SCpnt->SCp.Message = 0;
- SCpnt->SCp.Status = 0;
+ scsi_pointer->Message = 0;
+ scsi_pointer->Status = 0;
SCpnt->host_scribble = (void *)fas216_rq_sns_done;

/*
diff --git a/drivers/scsi/arm/fas216.h b/drivers/scsi/arm/fas216.h
index abf960487314..08113277a2a9 100644
--- a/drivers/scsi/arm/fas216.h
+++ b/drivers/scsi/arm/fas216.h
@@ -312,6 +312,10 @@ typedef struct {

/* driver-private data per SCSI command. */
struct fas216_cmd_priv {
+ /*
+ * @scsi_pointer must be the first member. See also arm_scsi_pointer().
+ */
+ struct scsi_pointer scsi_pointer;
void (*scsi_done)(struct scsi_cmnd *cmd);
};