kernel_optimize_test/drivers/s390/block/dasd_erp.c
Stefan Weinhuber a4d26c6aec [S390] dasd: do path verification for paths added at runtime
When a new path is added at runtime, the CIO layer will call the drivers
path_event callback. The DASD device driver uses this callback to trigger
a path verification for the new path. The driver will use only those
paths for I/O, which have been successfully verified.

Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-01-05 12:47:30 +01:00

186 lines
4.8 KiB
C

/*
* File...........: linux/drivers/s390/block/dasd.c
* Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
* Horst Hummel <Horst.Hummel@de.ibm.com>
* Carsten Otte <Cotte@de.ibm.com>
* Martin Schwidefsky <schwidefsky@de.ibm.com>
* Bugreports.to..: <Linux390@de.ibm.com>
* (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999-2001
*
*/
#define KMSG_COMPONENT "dasd"
#include <linux/ctype.h>
#include <linux/init.h>
#include <asm/debug.h>
#include <asm/ebcdic.h>
#include <asm/uaccess.h>
/* This is ugly... */
#define PRINTK_HEADER "dasd_erp:"
#include "dasd_int.h"
struct dasd_ccw_req *
dasd_alloc_erp_request(char *magic, int cplength, int datasize,
struct dasd_device * device)
{
unsigned long flags;
struct dasd_ccw_req *cqr;
char *data;
int size;
/* Sanity checks */
BUG_ON( magic == NULL || datasize > PAGE_SIZE ||
(cplength*sizeof(struct ccw1)) > PAGE_SIZE);
size = (sizeof(struct dasd_ccw_req) + 7L) & -8L;
if (cplength > 0)
size += cplength * sizeof(struct ccw1);
if (datasize > 0)
size += datasize;
spin_lock_irqsave(&device->mem_lock, flags);
cqr = (struct dasd_ccw_req *)
dasd_alloc_chunk(&device->erp_chunks, size);
spin_unlock_irqrestore(&device->mem_lock, flags);
if (cqr == NULL)
return ERR_PTR(-ENOMEM);
memset(cqr, 0, sizeof(struct dasd_ccw_req));
INIT_LIST_HEAD(&cqr->devlist);
INIT_LIST_HEAD(&cqr->blocklist);
data = (char *) cqr + ((sizeof(struct dasd_ccw_req) + 7L) & -8L);
cqr->cpaddr = NULL;
if (cplength > 0) {
cqr->cpaddr = (struct ccw1 *) data;
data += cplength*sizeof(struct ccw1);
memset(cqr->cpaddr, 0, cplength*sizeof(struct ccw1));
}
cqr->data = NULL;
if (datasize > 0) {
cqr->data = data;
memset(cqr->data, 0, datasize);
}
strncpy((char *) &cqr->magic, magic, 4);
ASCEBC((char *) &cqr->magic, 4);
set_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
dasd_get_device(device);
return cqr;
}
void
dasd_free_erp_request(struct dasd_ccw_req *cqr, struct dasd_device * device)
{
unsigned long flags;
spin_lock_irqsave(&device->mem_lock, flags);
dasd_free_chunk(&device->erp_chunks, cqr);
spin_unlock_irqrestore(&device->mem_lock, flags);
atomic_dec(&device->ref_count);
}
/*
* dasd_default_erp_action just retries the current cqr
*/
struct dasd_ccw_req *
dasd_default_erp_action(struct dasd_ccw_req *cqr)
{
struct dasd_device *device;
device = cqr->startdev;
/* just retry - there is nothing to save ... I got no sense data.... */
if (cqr->retries > 0) {
DBF_DEV_EVENT(DBF_DEBUG, device,
"default ERP called (%i retries left)",
cqr->retries);
if (!test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags))
cqr->lpm = device->path_data.opm;
cqr->status = DASD_CQR_FILLED;
} else {
pr_err("%s: default ERP has run out of retries and failed\n",
dev_name(&device->cdev->dev));
cqr->status = DASD_CQR_FAILED;
cqr->stopclk = get_clock();
}
return cqr;
} /* end dasd_default_erp_action */
/*
* DESCRIPTION
* Frees all ERPs of the current ERP Chain and set the status
* of the original CQR either to DASD_CQR_DONE if ERP was successful
* or to DASD_CQR_FAILED if ERP was NOT successful.
* NOTE: This function is only called if no discipline postaction
* is available
*
* PARAMETER
* erp current erp_head
*
* RETURN VALUES
* cqr pointer to the original CQR
*/
struct dasd_ccw_req *dasd_default_erp_postaction(struct dasd_ccw_req *cqr)
{
int success;
BUG_ON(cqr->refers == NULL || cqr->function == NULL);
success = cqr->status == DASD_CQR_DONE;
/* free all ERPs - but NOT the original cqr */
while (cqr->refers != NULL) {
struct dasd_ccw_req *refers;
refers = cqr->refers;
/* remove the request from the block queue */
list_del(&cqr->blocklist);
/* free the finished erp request */
dasd_free_erp_request(cqr, cqr->memdev);
cqr = refers;
}
/* set corresponding status to original cqr */
if (success)
cqr->status = DASD_CQR_DONE;
else {
cqr->status = DASD_CQR_FAILED;
cqr->stopclk = get_clock();
}
return cqr;
} /* end default_erp_postaction */
void
dasd_log_sense(struct dasd_ccw_req *cqr, struct irb *irb)
{
struct dasd_device *device;
device = cqr->startdev;
/* dump sense data */
if (device->discipline && device->discipline->dump_sense)
device->discipline->dump_sense(device, cqr, irb);
}
void
dasd_log_sense_dbf(struct dasd_ccw_req *cqr, struct irb *irb)
{
struct dasd_device *device;
device = cqr->startdev;
/* dump sense data to s390 debugfeature*/
if (device->discipline && device->discipline->dump_sense_dbf)
device->discipline->dump_sense_dbf(device, irb, "log");
}
EXPORT_SYMBOL(dasd_log_sense_dbf);
EXPORT_SYMBOL(dasd_default_erp_action);
EXPORT_SYMBOL(dasd_default_erp_postaction);
EXPORT_SYMBOL(dasd_alloc_erp_request);
EXPORT_SYMBOL(dasd_free_erp_request);
EXPORT_SYMBOL(dasd_log_sense);