[PATCH] s390: channel tape fixes
Tape driver fixes: - Added deferred condition handling to tape driver core. - Added ability to handle busy conditions. - Code cleanup. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
parent
6bb0e01081
commit
4111796d89
|
@ -3,10 +3,11 @@
|
|||
* tape device driver for 3480/3490E/3590 tapes.
|
||||
*
|
||||
* S390 and zSeries version
|
||||
* Copyright (C) 2001,2002 IBM Deutschland Entwicklung GmbH, IBM Corporation
|
||||
* Copyright (C) 2001,2005 IBM Deutschland Entwicklung GmbH, IBM Corporation
|
||||
* Author(s): Carsten Otte <cotte@de.ibm.com>
|
||||
* Tuan Ngo-Anh <ngoanh@de.ibm.com>
|
||||
* Martin Schwidefsky <schwidefsky@de.ibm.com>
|
||||
* Stefan Bader <shbader@de.ibm.com>
|
||||
*/
|
||||
|
||||
#ifndef _TAPE_H
|
||||
|
@ -111,6 +112,7 @@ enum tape_request_status {
|
|||
TAPE_REQUEST_QUEUED, /* request is queued to be processed */
|
||||
TAPE_REQUEST_IN_IO, /* request is currently in IO */
|
||||
TAPE_REQUEST_DONE, /* request is completed. */
|
||||
TAPE_REQUEST_CANCEL, /* request should be canceled. */
|
||||
};
|
||||
|
||||
/* Tape CCW request */
|
||||
|
@ -237,6 +239,9 @@ struct tape_device {
|
|||
/* Block dev frontend data */
|
||||
struct tape_blk_data blk_data;
|
||||
#endif
|
||||
|
||||
/* Function to start or stop the next request later. */
|
||||
struct work_struct tape_dnr;
|
||||
};
|
||||
|
||||
/* Externals from tape_core.c */
|
||||
|
|
|
@ -3,11 +3,12 @@
|
|||
* basic function of the tape device driver
|
||||
*
|
||||
* S390 and zSeries version
|
||||
* Copyright (C) 2001,2002 IBM Deutschland Entwicklung GmbH, IBM Corporation
|
||||
* Copyright (C) 2001,2005 IBM Deutschland Entwicklung GmbH, IBM Corporation
|
||||
* Author(s): Carsten Otte <cotte@de.ibm.com>
|
||||
* Michael Holzheu <holzheu@de.ibm.com>
|
||||
* Tuan Ngo-Anh <ngoanh@de.ibm.com>
|
||||
* Martin Schwidefsky <schwidefsky@de.ibm.com>
|
||||
* Stefan Bader <shbader@de.ibm.com>
|
||||
*/
|
||||
|
||||
#include <linux/config.h>
|
||||
|
@ -28,7 +29,7 @@
|
|||
#define PRINTK_HEADER "TAPE_CORE: "
|
||||
|
||||
static void __tape_do_irq (struct ccw_device *, unsigned long, struct irb *);
|
||||
static void __tape_remove_request(struct tape_device *, struct tape_request *);
|
||||
static void tape_delayed_next_request(void * data);
|
||||
|
||||
/*
|
||||
* One list to contain all tape devices of all disciplines, so
|
||||
|
@ -257,7 +258,7 @@ tape_med_state_set(struct tape_device *device, enum tape_medium_state newstate)
|
|||
* Stop running ccw. Has to be called with the device lock held.
|
||||
*/
|
||||
static inline int
|
||||
__tape_halt_io(struct tape_device *device, struct tape_request *request)
|
||||
__tape_cancel_io(struct tape_device *device, struct tape_request *request)
|
||||
{
|
||||
int retries;
|
||||
int rc;
|
||||
|
@ -270,21 +271,24 @@ __tape_halt_io(struct tape_device *device, struct tape_request *request)
|
|||
for (retries = 0; retries < 5; retries++) {
|
||||
rc = ccw_device_clear(device->cdev, (long) request);
|
||||
|
||||
if (rc == 0) { /* Termination successful */
|
||||
request->rc = -EIO;
|
||||
switch (rc) {
|
||||
case 0:
|
||||
request->status = TAPE_REQUEST_DONE;
|
||||
return 0;
|
||||
}
|
||||
|
||||
if (rc == -ENODEV)
|
||||
case -EBUSY:
|
||||
request->status = TAPE_REQUEST_CANCEL;
|
||||
schedule_work(&device->tape_dnr);
|
||||
return 0;
|
||||
case -ENODEV:
|
||||
DBF_EXCEPTION(2, "device gone, retry\n");
|
||||
else if (rc == -EIO)
|
||||
break;
|
||||
case -EIO:
|
||||
DBF_EXCEPTION(2, "I/O error, retry\n");
|
||||
else if (rc == -EBUSY)
|
||||
DBF_EXCEPTION(2, "device busy, retry late\n");
|
||||
else
|
||||
break;
|
||||
default:
|
||||
BUG();
|
||||
}
|
||||
}
|
||||
|
||||
return rc;
|
||||
}
|
||||
|
@ -473,6 +477,7 @@ tape_alloc_device(void)
|
|||
*device->modeset_byte = 0;
|
||||
device->first_minor = -1;
|
||||
atomic_set(&device->ref_count, 1);
|
||||
INIT_WORK(&device->tape_dnr, tape_delayed_next_request, device);
|
||||
|
||||
return device;
|
||||
}
|
||||
|
@ -708,54 +713,119 @@ tape_free_request (struct tape_request * request)
|
|||
kfree(request);
|
||||
}
|
||||
|
||||
static inline int
|
||||
__tape_start_io(struct tape_device *device, struct tape_request *request)
|
||||
{
|
||||
int rc;
|
||||
|
||||
#ifdef CONFIG_S390_TAPE_BLOCK
|
||||
if (request->op == TO_BLOCK)
|
||||
device->discipline->check_locate(device, request);
|
||||
#endif
|
||||
rc = ccw_device_start(
|
||||
device->cdev,
|
||||
request->cpaddr,
|
||||
(unsigned long) request,
|
||||
0x00,
|
||||
request->options
|
||||
);
|
||||
if (rc == 0) {
|
||||
request->status = TAPE_REQUEST_IN_IO;
|
||||
} else if (rc == -EBUSY) {
|
||||
/* The common I/O subsystem is currently busy. Retry later. */
|
||||
request->status = TAPE_REQUEST_QUEUED;
|
||||
schedule_work(&device->tape_dnr);
|
||||
rc = 0;
|
||||
} else {
|
||||
/* Start failed. Remove request and indicate failure. */
|
||||
DBF_EVENT(1, "tape: start request failed with RC = %i\n", rc);
|
||||
}
|
||||
return rc;
|
||||
}
|
||||
|
||||
static inline void
|
||||
__tape_do_io_list(struct tape_device *device)
|
||||
__tape_start_next_request(struct tape_device *device)
|
||||
{
|
||||
struct list_head *l, *n;
|
||||
struct tape_request *request;
|
||||
int rc;
|
||||
|
||||
DBF_LH(6, "__tape_do_io_list(%p)\n", device);
|
||||
DBF_LH(6, "__tape_start_next_request(%p)\n", device);
|
||||
/*
|
||||
* Try to start each request on request queue until one is
|
||||
* started successful.
|
||||
*/
|
||||
list_for_each_safe(l, n, &device->req_queue) {
|
||||
request = list_entry(l, struct tape_request, list);
|
||||
#ifdef CONFIG_S390_TAPE_BLOCK
|
||||
if (request->op == TO_BLOCK)
|
||||
device->discipline->check_locate(device, request);
|
||||
#endif
|
||||
rc = ccw_device_start(device->cdev, request->cpaddr,
|
||||
(unsigned long) request, 0x00,
|
||||
request->options);
|
||||
if (rc == 0) {
|
||||
request->status = TAPE_REQUEST_IN_IO;
|
||||
break;
|
||||
}
|
||||
/* Start failed. Remove request and indicate failure. */
|
||||
DBF_EVENT(1, "tape: DOIO failed with er = %i\n", rc);
|
||||
|
||||
/* Set ending status and do callback. */
|
||||
/*
|
||||
* Avoid race condition if bottom-half was triggered more than
|
||||
* once.
|
||||
*/
|
||||
if (request->status == TAPE_REQUEST_IN_IO)
|
||||
return;
|
||||
|
||||
/*
|
||||
* We wanted to cancel the request but the common I/O layer
|
||||
* was busy at that time. This can only happen if this
|
||||
* function is called by delayed_next_request.
|
||||
* Otherwise we start the next request on the queue.
|
||||
*/
|
||||
if (request->status == TAPE_REQUEST_CANCEL) {
|
||||
rc = __tape_cancel_io(device, request);
|
||||
} else {
|
||||
rc = __tape_start_io(device, request);
|
||||
}
|
||||
if (rc == 0)
|
||||
return;
|
||||
|
||||
/* Set ending status. */
|
||||
request->rc = rc;
|
||||
request->status = TAPE_REQUEST_DONE;
|
||||
__tape_remove_request(device, request);
|
||||
}
|
||||
}
|
||||
|
||||
static void
|
||||
__tape_remove_request(struct tape_device *device, struct tape_request *request)
|
||||
{
|
||||
/* Remove from request queue. */
|
||||
list_del(&request->list);
|
||||
|
||||
/* Do callback. */
|
||||
if (request->callback != NULL)
|
||||
request->callback(request, request->callback_data);
|
||||
}
|
||||
}
|
||||
|
||||
static void
|
||||
tape_delayed_next_request(void *data)
|
||||
{
|
||||
struct tape_device * device;
|
||||
|
||||
device = (struct tape_device *) data;
|
||||
DBF_LH(6, "tape_delayed_next_request(%p)\n", device);
|
||||
spin_lock_irq(get_ccwdev_lock(device->cdev));
|
||||
__tape_start_next_request(device);
|
||||
spin_unlock_irq(get_ccwdev_lock(device->cdev));
|
||||
}
|
||||
|
||||
static inline void
|
||||
__tape_end_request(
|
||||
struct tape_device * device,
|
||||
struct tape_request * request,
|
||||
int rc)
|
||||
{
|
||||
DBF_LH(6, "__tape_end_request(%p, %p, %i)\n", device, request, rc);
|
||||
if (request) {
|
||||
request->rc = rc;
|
||||
request->status = TAPE_REQUEST_DONE;
|
||||
|
||||
/* Remove from request queue. */
|
||||
list_del(&request->list);
|
||||
|
||||
/* Do callback. */
|
||||
if (request->callback != NULL)
|
||||
request->callback(request, request->callback_data);
|
||||
}
|
||||
|
||||
/* Start next request. */
|
||||
if (!list_empty(&device->req_queue))
|
||||
__tape_do_io_list(device);
|
||||
__tape_start_next_request(device);
|
||||
}
|
||||
|
||||
/*
|
||||
|
@ -812,7 +882,7 @@ tape_dump_sense_dbf(struct tape_device *device, struct tape_request *request,
|
|||
* the device lock held.
|
||||
*/
|
||||
static inline int
|
||||
__tape_do_io(struct tape_device *device, struct tape_request *request)
|
||||
__tape_start_request(struct tape_device *device, struct tape_request *request)
|
||||
{
|
||||
int rc;
|
||||
|
||||
|
@ -837,24 +907,16 @@ __tape_do_io(struct tape_device *device, struct tape_request *request)
|
|||
|
||||
if (list_empty(&device->req_queue)) {
|
||||
/* No other requests are on the queue. Start this one. */
|
||||
#ifdef CONFIG_S390_TAPE_BLOCK
|
||||
if (request->op == TO_BLOCK)
|
||||
device->discipline->check_locate(device, request);
|
||||
#endif
|
||||
rc = ccw_device_start(device->cdev, request->cpaddr,
|
||||
(unsigned long) request, 0x00,
|
||||
request->options);
|
||||
if (rc) {
|
||||
DBF_EVENT(1, "tape: DOIO failed with rc = %i\n", rc);
|
||||
rc = __tape_start_io(device, request);
|
||||
if (rc)
|
||||
return rc;
|
||||
}
|
||||
|
||||
DBF_LH(5, "Request %p added for execution.\n", request);
|
||||
list_add(&request->list, &device->req_queue);
|
||||
request->status = TAPE_REQUEST_IN_IO;
|
||||
} else {
|
||||
DBF_LH(5, "Request %p add to queue.\n", request);
|
||||
list_add_tail(&request->list, &device->req_queue);
|
||||
request->status = TAPE_REQUEST_QUEUED;
|
||||
list_add_tail(&request->list, &device->req_queue);
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
@ -872,7 +934,7 @@ tape_do_io_async(struct tape_device *device, struct tape_request *request)
|
|||
|
||||
spin_lock_irq(get_ccwdev_lock(device->cdev));
|
||||
/* Add request to request queue and try to start it. */
|
||||
rc = __tape_do_io(device, request);
|
||||
rc = __tape_start_request(device, request);
|
||||
spin_unlock_irq(get_ccwdev_lock(device->cdev));
|
||||
return rc;
|
||||
}
|
||||
|
@ -901,7 +963,7 @@ tape_do_io(struct tape_device *device, struct tape_request *request)
|
|||
request->callback = __tape_wake_up;
|
||||
request->callback_data = &wq;
|
||||
/* Add request to request queue and try to start it. */
|
||||
rc = __tape_do_io(device, request);
|
||||
rc = __tape_start_request(device, request);
|
||||
spin_unlock_irq(get_ccwdev_lock(device->cdev));
|
||||
if (rc)
|
||||
return rc;
|
||||
|
@ -935,7 +997,7 @@ tape_do_io_interruptible(struct tape_device *device,
|
|||
/* Setup callback */
|
||||
request->callback = __tape_wake_up_interruptible;
|
||||
request->callback_data = &wq;
|
||||
rc = __tape_do_io(device, request);
|
||||
rc = __tape_start_request(device, request);
|
||||
spin_unlock_irq(get_ccwdev_lock(device->cdev));
|
||||
if (rc)
|
||||
return rc;
|
||||
|
@ -944,35 +1006,26 @@ tape_do_io_interruptible(struct tape_device *device,
|
|||
if (rc != -ERESTARTSYS)
|
||||
/* Request finished normally. */
|
||||
return request->rc;
|
||||
|
||||
/* Interrupted by a signal. We have to stop the current request. */
|
||||
spin_lock_irq(get_ccwdev_lock(device->cdev));
|
||||
rc = __tape_halt_io(device, request);
|
||||
rc = __tape_cancel_io(device, request);
|
||||
spin_unlock_irq(get_ccwdev_lock(device->cdev));
|
||||
if (rc == 0) {
|
||||
/* Wait for the interrupt that acknowledges the halt. */
|
||||
do {
|
||||
rc = wait_event_interruptible(
|
||||
wq,
|
||||
(request->callback == NULL)
|
||||
);
|
||||
} while (rc != -ERESTARTSYS);
|
||||
|
||||
DBF_EVENT(3, "IO stopped on %08x\n", device->cdev_id);
|
||||
rc = -ERESTARTSYS;
|
||||
}
|
||||
spin_unlock_irq(get_ccwdev_lock(device->cdev));
|
||||
return rc;
|
||||
}
|
||||
|
||||
/*
|
||||
* Handle requests that return an i/o error in the irb.
|
||||
*/
|
||||
static inline void
|
||||
tape_handle_killed_request(
|
||||
struct tape_device *device,
|
||||
struct tape_request *request)
|
||||
{
|
||||
if(request != NULL) {
|
||||
/* Set ending status. FIXME: Should the request be retried? */
|
||||
request->rc = -EIO;
|
||||
request->status = TAPE_REQUEST_DONE;
|
||||
__tape_remove_request(device, request);
|
||||
} else {
|
||||
__tape_do_io_list(device);
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* Tape interrupt routine, called from the ccw_device layer
|
||||
*/
|
||||
|
@ -981,7 +1034,6 @@ __tape_do_irq (struct ccw_device *cdev, unsigned long intparm, struct irb *irb)
|
|||
{
|
||||
struct tape_device *device;
|
||||
struct tape_request *request;
|
||||
int final;
|
||||
int rc;
|
||||
|
||||
device = (struct tape_device *) cdev->dev.driver_data;
|
||||
|
@ -996,12 +1048,13 @@ __tape_do_irq (struct ccw_device *cdev, unsigned long intparm, struct irb *irb)
|
|||
|
||||
/* On special conditions irb is an error pointer */
|
||||
if (IS_ERR(irb)) {
|
||||
/* FIXME: What to do with the request? */
|
||||
switch (PTR_ERR(irb)) {
|
||||
case -ETIMEDOUT:
|
||||
PRINT_WARN("(%s): Request timed out\n",
|
||||
cdev->dev.bus_id);
|
||||
case -EIO:
|
||||
tape_handle_killed_request(device, request);
|
||||
__tape_end_request(device, request, -EIO);
|
||||
break;
|
||||
default:
|
||||
PRINT_ERR("(%s): Unexpected i/o error %li\n",
|
||||
|
@ -1011,6 +1064,21 @@ __tape_do_irq (struct ccw_device *cdev, unsigned long intparm, struct irb *irb)
|
|||
return;
|
||||
}
|
||||
|
||||
/*
|
||||
* If the condition code is not zero and the start function bit is
|
||||
* still set, this is an deferred error and the last start I/O did
|
||||
* not succeed. Restart the request now.
|
||||
*/
|
||||
if (irb->scsw.cc != 0 && (irb->scsw.fctl & SCSW_FCTL_START_FUNC)) {
|
||||
PRINT_WARN("(%s): deferred cc=%i. restaring\n",
|
||||
cdev->dev.bus_id,
|
||||
irb->scsw.cc);
|
||||
rc = __tape_start_io(device, request);
|
||||
if (rc)
|
||||
__tape_end_request(device, request, rc);
|
||||
return;
|
||||
}
|
||||
|
||||
/* May be an unsolicited irq */
|
||||
if(request != NULL)
|
||||
request->rescnt = irb->scsw.count;
|
||||
|
@ -1042,7 +1110,7 @@ __tape_do_irq (struct ccw_device *cdev, unsigned long intparm, struct irb *irb)
|
|||
* To detect these request the state will be set to TAPE_REQUEST_DONE.
|
||||
*/
|
||||
if(request != NULL && request->status == TAPE_REQUEST_DONE) {
|
||||
__tape_remove_request(device, request);
|
||||
__tape_end_request(device, request, -EIO);
|
||||
return;
|
||||
}
|
||||
|
||||
|
@ -1054,51 +1122,34 @@ __tape_do_irq (struct ccw_device *cdev, unsigned long intparm, struct irb *irb)
|
|||
* rc == TAPE_IO_RETRY: request finished but needs another go.
|
||||
* rc == TAPE_IO_STOP: request needs to get terminated.
|
||||
*/
|
||||
final = 0;
|
||||
switch (rc) {
|
||||
case TAPE_IO_SUCCESS:
|
||||
/* Upon normal completion the device _is_ online */
|
||||
device->tape_generic_status |= GMT_ONLINE(~0);
|
||||
final = 1;
|
||||
__tape_end_request(device, request, rc);
|
||||
break;
|
||||
case TAPE_IO_PENDING:
|
||||
break;
|
||||
case TAPE_IO_RETRY:
|
||||
#ifdef CONFIG_S390_TAPE_BLOCK
|
||||
if (request->op == TO_BLOCK)
|
||||
device->discipline->check_locate(device, request);
|
||||
#endif
|
||||
rc = ccw_device_start(cdev, request->cpaddr,
|
||||
(unsigned long) request, 0x00,
|
||||
request->options);
|
||||
if (rc) {
|
||||
DBF_EVENT(1, "tape: DOIO failed with er = %i\n", rc);
|
||||
final = 1;
|
||||
}
|
||||
rc = __tape_start_io(device, request);
|
||||
if (rc)
|
||||
__tape_end_request(device, request, rc);
|
||||
break;
|
||||
case TAPE_IO_STOP:
|
||||
__tape_halt_io(device, request);
|
||||
rc = __tape_cancel_io(device, request);
|
||||
if (rc)
|
||||
__tape_end_request(device, request, rc);
|
||||
break;
|
||||
default:
|
||||
if (rc > 0) {
|
||||
DBF_EVENT(6, "xunknownrc\n");
|
||||
PRINT_ERR("Invalid return code from discipline "
|
||||
"interrupt function.\n");
|
||||
rc = -EIO;
|
||||
}
|
||||
final = 1;
|
||||
break;
|
||||
}
|
||||
if (final) {
|
||||
/* May be an unsolicited irq */
|
||||
if(request != NULL) {
|
||||
/* Set ending status. */
|
||||
request->rc = rc;
|
||||
request->status = TAPE_REQUEST_DONE;
|
||||
__tape_remove_request(device, request);
|
||||
__tape_end_request(device, request, -EIO);
|
||||
} else {
|
||||
__tape_do_io_list(device);
|
||||
__tape_end_request(device, request, rc);
|
||||
}
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
|
@ -1191,7 +1242,7 @@ tape_init (void)
|
|||
#ifdef DBF_LIKE_HELL
|
||||
debug_set_level(TAPE_DBF_AREA, 6);
|
||||
#endif
|
||||
DBF_EVENT(3, "tape init: ($Revision: 1.51 $)\n");
|
||||
DBF_EVENT(3, "tape init: ($Revision: 1.54 $)\n");
|
||||
tape_proc_init();
|
||||
tapechar_init ();
|
||||
tapeblock_init ();
|
||||
|
@ -1216,7 +1267,7 @@ tape_exit(void)
|
|||
MODULE_AUTHOR("(C) 2001 IBM Deutschland Entwicklung GmbH by Carsten Otte and "
|
||||
"Michael Holzheu (cotte@de.ibm.com,holzheu@de.ibm.com)");
|
||||
MODULE_DESCRIPTION("Linux on zSeries channel attached "
|
||||
"tape device driver ($Revision: 1.51 $)");
|
||||
"tape device driver ($Revision: 1.54 $)");
|
||||
MODULE_LICENSE("GPL");
|
||||
|
||||
module_init(tape_init);
|
||||
|
|
Loading…
Reference in New Issue