dasd_erp.c

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/*
 * Author(s)......: Holger Smolinski <[email protected]>
 *          Horst Hummel <[email protected]>
 *          Carsten Otte <[email protected]>
 *          Martin Schwidefsky <[email protected]>
 * Bugreports.to..: <[email protected]>
 * Copyright IBM Corp. 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);