[PATCH v3 35/37] atari_NCR5380: Move static co-routine variables to host data

Finn Thain
2014-11-12T05:12:21Z

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[-- Type: text/plain, Size: 8008 bytes --]

Unlike NCR5380.c, the atari_NCR5380.c core driver is limited to a single
instance because co-routine state is stored globally.

Fix this by removing the static scsi host pointer. For the co-routine,
obtain this pointer from the work_struct pointer instead. For the interrupt
handler, obtain it from the dev_id argument.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>

---
drivers/scsi/NCR5380.h | 2 +
drivers/scsi/atari_NCR5380.c | 61 +++++++++++++++----------------------------
drivers/scsi/atari_scsi.c | 8 ++---
3 files changed, 28 insertions(+), 43 deletions(-)

Index: linux/drivers/scsi/NCR5380.h
===================================================================
--- linux.orig/drivers/scsi/NCR5380.h 2014-11-12 16:11:41.000000000 +1100
+++ linux/drivers/scsi/NCR5380.h 2014-11-12 16:11:42.000000000 +1100
@@ -283,6 +283,8 @@ struct NCR5380_hostdata {
int read_overruns; /* number of bytes to cut from a
* transfer to handle chip overruns */
int retain_dma_intr;
+ struct work_struct main_task;
+ volatile int main_running;
#ifdef SUPPORT_TAGS
struct tag_alloc TagAlloc[8][8]; /* 8 targets and 8 LUNs */
#endif
Index: linux/drivers/scsi/atari_NCR5380.c
===================================================================
--- linux.orig/drivers/scsi/atari_NCR5380.c 2014-11-12 16:11:41.000000000 +1100
+++ linux/drivers/scsi/atari_NCR5380.c 2014-11-12 16:11:42.000000000 +1100
@@ -221,9 +221,6 @@
* possible) function may be used.
*/

-static struct Scsi_Host *first_instance = NULL;
-static struct scsi_host_template *the_template = NULL;
-
/* Macros ease life... :-) */
#define SETUP_HOSTDATA(in) \
struct NCR5380_hostdata *hostdata = \
@@ -595,32 +592,19 @@ static void NCR5380_print_phase(struct S
#include <linux/workqueue.h>
#include <linux/interrupt.h>

-static volatile int main_running;
-static DECLARE_WORK(NCR5380_tqueue, NCR5380_main);
-
-static inline void queue_main(void)
+static inline void queue_main(struct NCR5380_hostdata *hostdata)
{
- if (!main_running) {
+ if (!hostdata->main_running) {
/* If in interrupt and NCR5380_main() not already running,
queue it on the 'immediate' task queue, to be processed
immediately after the current interrupt processing has
finished. */
- schedule_work(&NCR5380_tqueue);
+ schedule_work(&hostdata->main_task);
}
/* else: nothing to do: the running NCR5380_main() will pick up
any newly queued command. */
}

-
-static inline void NCR5380_all_init(void)
-{
- static int done = 0;
- if (!done) {
- dprintk(NDEBUG_INIT, "scsi : NCR5380_all_init()\n");
- done = 1;
- }
-}
-
/**
* NCR58380_info - report driver and host information
* @instance: relevant scsi host instance
@@ -703,7 +687,7 @@ static void NCR5380_print_status(struct

local_irq_save(flags);
printk("NCR5380: coroutine is%s running.\n",
- main_running ? "" : "n't");
+ hostdata->main_running ? "" : "n't");
if (!hostdata->connected)
printk("scsi%d: no currently connected command\n", HOSTNO);
else
@@ -746,7 +730,7 @@ static int __maybe_unused NCR5380_show_i

local_irq_save(flags);
seq_printf(m, "NCR5380: coroutine is%s running.\n",
- main_running ? "" : "n't");
+ hostdata->main_running ? "" : "n't");
if (!hostdata->connected)
seq_printf(m, "scsi%d: no currently connected command\n", HOSTNO);
else
@@ -783,8 +767,7 @@ static int __init NCR5380_init(struct Sc
int i;
SETUP_HOSTDATA(instance);

- NCR5380_all_init();
-
+ hostdata->host = instance;
hostdata->aborted = 0;
hostdata->id_mask = 1 << instance->this_id;
hostdata->id_higher_mask = 0;
@@ -805,10 +788,7 @@ static int __init NCR5380_init(struct Sc
hostdata->disconnected_queue = NULL;
hostdata->flags = flags;

- if (!the_template) {
- the_template = instance->hostt;
- first_instance = instance;
- }
+ INIT_WORK(&hostdata->main_task, NCR5380_main);

prepare_info(instance);

@@ -829,7 +809,9 @@ static int __init NCR5380_init(struct Sc

static void NCR5380_exit(struct Scsi_Host *instance)
{
- cancel_work_sync(&NCR5380_tqueue);
+ struct NCR5380_hostdata *hostdata = shost_priv(instance);
+
+ cancel_work_sync(&hostdata->main_task);
}

/**
@@ -924,9 +906,9 @@ static int NCR5380_queue_command(struct
* unconditionally, because it cannot be already running.
*/
if (in_interrupt() || irqs_disabled())
- queue_main();
+ queue_main(hostdata);
else
- NCR5380_main(NULL);
+ NCR5380_main(&hostdata->main_task);
return 0;
}

@@ -955,9 +937,10 @@ static inline void maybe_release_dma_irq

static void NCR5380_main(struct work_struct *work)
{
+ struct NCR5380_hostdata *hostdata =
+ container_of(work, struct NCR5380_hostdata, main_task);
+ struct Scsi_Host *instance = hostdata->host;
struct scsi_cmnd *tmp, *prev;
- struct Scsi_Host *instance = first_instance;
- struct NCR5380_hostdata *hostdata = HOSTDATA(instance);
int done;
unsigned long flags;

@@ -982,9 +965,9 @@ static void NCR5380_main(struct work_str
'main_running' is set here, and queues/executes main via the
task queue, it doesn't do any harm, just this instance of main
won't find any work left to do. */
- if (main_running)
+ if (hostdata->main_running)
return;
- main_running = 1;
+ hostdata->main_running = 1;

local_save_flags(flags);
do {
@@ -1103,7 +1086,7 @@ static void NCR5380_main(struct work_str
/* Better allow ints _after_ 'main_running' has been cleared, else
an interrupt could believe we'll pick up the work it left for
us, but we won't see it anymore here... */
- main_running = 0;
+ hostdata->main_running = 0;
local_irq_restore(flags);
}

@@ -1215,7 +1198,7 @@ static void NCR5380_dma_complete(struct

static irqreturn_t NCR5380_intr(int irq, void *dev_id)
{
- struct Scsi_Host *instance = first_instance;
+ struct Scsi_Host *instance = dev_id;
int done = 1, handled = 0;
unsigned char basr;

@@ -1287,7 +1270,7 @@ static irqreturn_t NCR5380_intr(int irq,
if (!done) {
dprintk(NDEBUG_INTR, "scsi%d: in int routine, calling main\n", HOSTNO);
/* Put a call to NCR5380_main() on the queue... */
- queue_main();
+ queue_main(shost_priv(instance));
}
return IRQ_RETVAL(handled);
}
@@ -1767,7 +1750,7 @@ static int NCR5380_transfer_pio(struct S
* Returns : 0 on success, -1 on failure.
*/

-static int do_abort(struct Scsi_Host *host)
+static int do_abort(struct Scsi_Host *instance)
{
unsigned char tmp, *msgptr, phase;
int len;
@@ -1802,7 +1785,7 @@ static int do_abort(struct Scsi_Host *ho
msgptr = &tmp;
len = 1;
phase = PHASE_MSGOUT;
- NCR5380_transfer_pio(host, &phase, &len, &msgptr);
+ NCR5380_transfer_pio(instance, &phase, &len, &msgptr);

/*
* If we got here, and the command completed successfully,
Index: linux/drivers/scsi/atari_scsi.c
===================================================================
--- linux.orig/drivers/scsi/atari_scsi.c 2014-11-12 16:11:39.000000000 +1100
+++ linux/drivers/scsi/atari_scsi.c 2014-11-12 16:11:42.000000000 +1100
@@ -110,7 +110,7 @@
#define NCR5380_dma_xfer_len(instance, cmd, phase) \
atari_dma_xfer_len(cmd->SCp.this_residual, cmd, !((phase) & SR_IO))

-#define NCR5380_acquire_dma_irq(instance) falcon_get_lock()
+#define NCR5380_acquire_dma_irq(instance) falcon_get_lock(instance)
#define NCR5380_release_dma_irq(instance) falcon_release_lock()

#include "NCR5380.h"
@@ -468,15 +468,15 @@ static void falcon_release_lock(void)
* command immediately but tell the SCSI mid-layer to defer.
*/

-static int falcon_get_lock(void)
+static int falcon_get_lock(struct Scsi_Host *instance)
{
if (IS_A_TT())
return 1;

if (in_interrupt())
- return stdma_try_lock(scsi_falcon_intr, NULL);
+ return stdma_try_lock(scsi_falcon_intr, instance);

- stdma_lock(scsi_falcon_intr, NULL);
+ stdma_lock(scsi_falcon_intr, instance);
return 1;
}