[PATCH] s390: tape 3590 changes

[mirror_ubuntu-zesty-kernel.git] / drivers / s390 / char / tape_3590.c

/*
 *  drivers/s390/char/tape_3590.c
 *    tape device discipline for 3590 tapes.
 *
 *    Copyright (C) IBM Corp. 2001,2006
 *    Author(s): Stefan Bader <shbader@de.ibm.com>
 *               Michael Holzheu <holzheu@de.ibm.com>
 *               Martin Schwidefsky <schwidefsky@de.ibm.com>
 */

#include <linux/config.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/bio.h>

#define TAPE_DBF_AREA   tape_3590_dbf

#include "tape.h"
#include "tape_std.h"
#include "tape_3590.h"

/*
 * Pointer to debug area.
 */
debug_info_t *TAPE_DBF_AREA = NULL;
EXPORT_SYMBOL(TAPE_DBF_AREA);

/*******************************************************************
 * Error Recovery fuctions:
 * - Read Opposite:              implemented
 * - Read Device (buffered) log: BRA
 * - Read Library log:           BRA
 * - Swap Devices:               BRA
 * - Long Busy:                  BRA
 * - Special Intercept:          BRA
 * - Read Alternate:             implemented
 *******************************************************************/

#define PRINTK_HEADER "TAPE_3590: "

static const char *tape_3590_msg[TAPE_3590_MAX_MSG] = {
        [0x00] = "",
        [0x10] = "Lost Sense",
        [0x11] = "Assigned Elsewhere",
        [0x12] = "Allegiance Reset",
        [0x13] = "Shared Access Violation",
        [0x20] = "Command Reject",
        [0x21] = "Configuration Error",
        [0x22] = "Protection Exception",
        [0x23] = "Write Protect",
        [0x24] = "Write Length",
        [0x25] = "Read-Only Format",
        [0x31] = "Beginning of Partition",
        [0x33] = "End of Partition",
        [0x34] = "End of Data",
        [0x35] = "Block not found",
        [0x40] = "Device Intervention",
        [0x41] = "Loader Intervention",
        [0x42] = "Library Intervention",
        [0x50] = "Write Error",
        [0x51] = "Erase Error",
        [0x52] = "Formatting Error",
        [0x53] = "Read Error",
        [0x54] = "Unsupported Format",
        [0x55] = "No Formatting",
        [0x56] = "Positioning lost",
        [0x57] = "Read Length",
        [0x60] = "Unsupported Medium",
        [0x61] = "Medium Length Error",
        [0x62] = "Medium removed",
        [0x64] = "Load Check",
        [0x65] = "Unload Check",
        [0x70] = "Equipment Check",
        [0x71] = "Bus out Check",
        [0x72] = "Protocol Error",
        [0x73] = "Interface Error",
        [0x74] = "Overrun",
        [0x75] = "Halt Signal",
        [0x90] = "Device fenced",
        [0x91] = "Device Path fenced",
        [0xa0] = "Volume misplaced",
        [0xa1] = "Volume inaccessible",
        [0xa2] = "Volume in input",
        [0xa3] = "Volume ejected",
        [0xa4] = "All categories reserved",
        [0xa5] = "Duplicate Volume",
        [0xa6] = "Library Manager Offline",
        [0xa7] = "Library Output Station full",
        [0xa8] = "Vision System non-operational",
        [0xa9] = "Library Manager Equipment Check",
        [0xaa] = "Library Equipment Check",
        [0xab] = "All Library Cells full",
        [0xac] = "No Cleaner Volumes in Library",
        [0xad] = "I/O Station door open",
        [0xae] = "Subsystem environmental alert",
};

/*
 * 3590 IOCTL Overload
 */
static int
tape_3590_ioctl(struct tape_device *device, unsigned int cmd, unsigned long arg)
{
        switch (cmd) {
        case TAPE390_DISPLAY: {
                struct display_struct disp;

                if (copy_from_user(&disp, (char __user *) arg, sizeof(disp)))
                        return -EFAULT;

                return tape_std_display(device, &disp);
        }
        default:
                return -EINVAL; /* no additional ioctls */
        }
}

/*
 * SENSE Medium: Get Sense data about medium state
 */
static int
tape_3590_sense_medium(struct tape_device *device)
{
        struct tape_request *request;

        request = tape_alloc_request(1, 128);
        if (IS_ERR(request))
                return PTR_ERR(request);
        request->op = TO_MSEN;
        tape_ccw_end(request->cpaddr, MEDIUM_SENSE, 128, request->cpdata);
        return tape_do_io_free(device, request);
}

/*
 * MTTELL: Tell block. Return the number of block relative to current file.
 */
static int
tape_3590_mttell(struct tape_device *device, int mt_count)
{
        __u64 block_id;
        int rc;

        rc = tape_std_read_block_id(device, &block_id);
        if (rc)
                return rc;
        return block_id >> 32;
}

/*
 * MTSEEK: seek to the specified block.
 */
static int
tape_3590_mtseek(struct tape_device *device, int count)
{
        struct tape_request *request;

        DBF_EVENT(6, "xsee id: %x\n", count);
        request = tape_alloc_request(3, 4);
        if (IS_ERR(request))
                return PTR_ERR(request);
        request->op = TO_LBL;
        tape_ccw_cc(request->cpaddr, MODE_SET_DB, 1, device->modeset_byte);
        *(__u32 *) request->cpdata = count;
        tape_ccw_cc(request->cpaddr + 1, LOCATE, 4, request->cpdata);
        tape_ccw_end(request->cpaddr + 2, NOP, 0, NULL);
        return tape_do_io_free(device, request);
}

/*
 * Read Opposite Error Recovery Function:
 * Used, when Read Forward does not work
 */
static void
tape_3590_read_opposite(struct tape_device *device,
                        struct tape_request *request)
{
        struct tape_3590_disc_data *data;

        /*
         * We have allocated 4 ccws in tape_std_read, so we can now
         * transform the request to a read backward, followed by a
         * forward space block.
         */
        request->op = TO_RBA;
        tape_ccw_cc(request->cpaddr, MODE_SET_DB, 1, device->modeset_byte);
        data = device->discdata;
        tape_ccw_cc_idal(request->cpaddr + 1, data->read_back_op,
                         device->char_data.idal_buf);
        tape_ccw_cc(request->cpaddr + 2, FORSPACEBLOCK, 0, NULL);
        tape_ccw_end(request->cpaddr + 3, NOP, 0, NULL);
        DBF_EVENT(6, "xrop ccwg\n");
}

/*
 * Read Attention Msg
 * This should be done after an interrupt with attention bit (0x80)
 * in device state.
 *
 * After a "read attention message" request there are two possible
 * results:
 *
 * 1. A unit check is presented, when attention sense is present (e.g. when
 * a medium has been unloaded). The attention sense comes then
 * together with the unit check. The recovery action is either "retry"
 * (in case there is an attention message pending) or "permanent error".
 *
 * 2. The attention msg is written to the "read subsystem data" buffer.
 * In this case we probably should print it to the console.
 */
static int
tape_3590_read_attmsg(struct tape_device *device)
{
        struct tape_request *request;
        char *buf;

        request = tape_alloc_request(3, 4096);
        if (IS_ERR(request))
                return PTR_ERR(request);
        request->op = TO_READ_ATTMSG;
        buf = request->cpdata;
        buf[0] = PREP_RD_SS_DATA;
        buf[6] = RD_ATTMSG;     /* read att msg */
        tape_ccw_cc(request->cpaddr, PERFORM_SS_FUNC, 12, buf);
        tape_ccw_cc(request->cpaddr + 1, READ_SS_DATA, 4096 - 12, buf + 12);
        tape_ccw_end(request->cpaddr + 2, NOP, 0, NULL);
        return tape_do_io_free(device, request);
}

/*
 * These functions are used to schedule follow-up actions from within an
 * interrupt context (like unsolicited interrupts).
 */
struct work_handler_data {
        struct tape_device *device;
        enum tape_op        op;
        struct work_struct  work;
};

static void
tape_3590_work_handler(void *data)
{
        struct work_handler_data *p = data;

        switch (p->op) {
        case TO_MSEN:
                tape_3590_sense_medium(p->device);
                break;
        case TO_READ_ATTMSG:
                tape_3590_read_attmsg(p->device);
                break;
        default:
                DBF_EVENT(3, "T3590: work handler undefined for "
                          "operation 0x%02x\n", p->op);
        }
        tape_put_device(p->device);
        kfree(p);
}

static int
tape_3590_schedule_work(struct tape_device *device, enum tape_op op)
{
        struct work_handler_data *p;

        if ((p = kzalloc(sizeof(*p), GFP_ATOMIC)) == NULL)
                return -ENOMEM;

        INIT_WORK(&p->work, tape_3590_work_handler, p);

        p->device = tape_get_device_reference(device);
        p->op = op;

        schedule_work(&p->work);
        return 0;
}

#ifdef CONFIG_S390_TAPE_BLOCK
/*
 * Tape Block READ
 */
static struct tape_request *
tape_3590_bread(struct tape_device *device, struct request *req)
{
        struct tape_request *request;
        struct ccw1 *ccw;
        int count = 0, start_block, i;
        unsigned off;
        char *dst;
        struct bio_vec *bv;
        struct bio *bio;

        DBF_EVENT(6, "xBREDid:");
        start_block = req->sector >> TAPEBLOCK_HSEC_S2B;
        DBF_EVENT(6, "start_block = %i\n", start_block);

        rq_for_each_bio(bio, req) {
                bio_for_each_segment(bv, bio, i) {
                        count += bv->bv_len >> (TAPEBLOCK_HSEC_S2B + 9);
                }
        }
        request = tape_alloc_request(2 + count + 1, 4);
        if (IS_ERR(request))
                return request;
        request->op = TO_BLOCK;
        *(__u32 *) request->cpdata = start_block;
        ccw = request->cpaddr;
        ccw = tape_ccw_cc(ccw, MODE_SET_DB, 1, device->modeset_byte);

        /*
         * We always setup a nop after the mode set ccw. This slot is
         * used in tape_std_check_locate to insert a locate ccw if the
         * current tape position doesn't match the start block to be read.
         */
        ccw = tape_ccw_cc(ccw, NOP, 0, NULL);

        rq_for_each_bio(bio, req) {
                bio_for_each_segment(bv, bio, i) {
                        dst = page_address(bv->bv_page) + bv->bv_offset;
                        for (off = 0; off < bv->bv_len;
                             off += TAPEBLOCK_HSEC_SIZE) {
                                ccw->flags = CCW_FLAG_CC;
                                ccw->cmd_code = READ_FORWARD;
                                ccw->count = TAPEBLOCK_HSEC_SIZE;
                                set_normalized_cda(ccw, (void *) __pa(dst));
                                ccw++;
                                dst += TAPEBLOCK_HSEC_SIZE;
                        }
                        if (off > bv->bv_len)
                                BUG();
                }
        }
        ccw = tape_ccw_end(ccw, NOP, 0, NULL);
        DBF_EVENT(6, "xBREDccwg\n");
        return request;
}

static void
tape_3590_free_bread(struct tape_request *request)
{
        struct ccw1 *ccw;

        /* Last ccw is a nop and doesn't need clear_normalized_cda */
        for (ccw = request->cpaddr; ccw->flags & CCW_FLAG_CC; ccw++)
                if (ccw->cmd_code == READ_FORWARD)
                        clear_normalized_cda(ccw);
        tape_free_request(request);
}

/*
 * check_locate is called just before the tape request is passed to
 * the common io layer for execution. It has to check the current
 * tape position and insert a locate ccw if it doesn't match the
 * start block for the request.
 */
static void
tape_3590_check_locate(struct tape_device *device, struct tape_request *request)
{
        __u32 *start_block;

        start_block = (__u32 *) request->cpdata;
        if (*start_block != device->blk_data.block_position) {
                /* Add the start offset of the file to get the real block. */
                *start_block += device->bof;
                tape_ccw_cc(request->cpaddr + 1, LOCATE, 4, request->cpdata);
        }
}
#endif

/*
 * The done handler is called at device/channel end and wakes up the sleeping
 * process
 */
static int
tape_3590_done(struct tape_device *device, struct tape_request *request)
{
        struct tape_3590_med_sense *sense;

        DBF_EVENT(6, "%s done\n", tape_op_verbose[request->op]);

        switch (request->op) {
        case TO_BSB:
        case TO_BSF:
        case TO_DSE:
        case TO_FSB:
        case TO_FSF:
        case TO_LBL:
        case TO_RFO:
        case TO_RBA:
        case TO_REW:
        case TO_WRI:
        case TO_WTM:
        case TO_BLOCK:
        case TO_LOAD:
                tape_med_state_set(device, MS_LOADED);
                break;
        case TO_RUN:
                tape_med_state_set(device, MS_UNLOADED);
                break;
        case TO_MSEN:
                sense = (struct tape_3590_med_sense *) request->cpdata;
                if (sense->masst == MSENSE_UNASSOCIATED)
                        tape_med_state_set(device, MS_UNLOADED);
                if (sense->masst == MSENSE_ASSOCIATED_MOUNT)
                        tape_med_state_set(device, MS_LOADED);
                break;
        case TO_RBI:    /* RBI seems to succeed even without medium loaded. */
        case TO_NOP:    /* Same to NOP. */
        case TO_READ_CONFIG:
        case TO_READ_ATTMSG:
        case TO_DIS:
        case TO_ASSIGN:
        case TO_UNASSIGN:
                break;
        case TO_SIZE:
                break;
        }
        return TAPE_IO_SUCCESS;
}

/*
 * This fuction is called, when error recovery was successfull
 */
static inline int
tape_3590_erp_succeded(struct tape_device *device, struct tape_request *request)
{
        DBF_EVENT(3, "Error Recovery successfull for %s\n",
                  tape_op_verbose[request->op]);
        return tape_3590_done(device, request);
}

/*
 * This fuction is called, when error recovery was not successfull
 */
static inline int
tape_3590_erp_failed(struct tape_device *device, struct tape_request *request,
                     struct irb *irb, int rc)
{
        DBF_EVENT(3, "Error Recovery failed for %s\n",
                  tape_op_verbose[request->op]);
        tape_dump_sense_dbf(device, request, irb);
        return rc;
}

/*
 * Error Recovery do retry
 */
static inline int
tape_3590_erp_retry(struct tape_device *device, struct tape_request *request,
                    struct irb *irb)
{
        DBF_EVENT(2, "Retry: %s\n", tape_op_verbose[request->op]);
        tape_dump_sense_dbf(device, request, irb);
        return TAPE_IO_RETRY;
}

/*
 * Handle unsolicited interrupts
 */
static int
tape_3590_unsolicited_irq(struct tape_device *device, struct irb *irb)
{
        if (irb->scsw.dstat == DEV_STAT_CHN_END)
                /* Probably result of halt ssch */
                return TAPE_IO_PENDING;
        else if (irb->scsw.dstat == 0x85)
                /* Device Ready -> check medium state */
                tape_3590_schedule_work(device, TO_MSEN);
        else if (irb->scsw.dstat & DEV_STAT_ATTENTION)
                tape_3590_schedule_work(device, TO_READ_ATTMSG);
        else {
                DBF_EVENT(3, "unsol.irq! dev end: %08x\n", device->cdev_id);
                PRINT_WARN("Unsolicited IRQ (Device End) caught.\n");
                tape_dump_sense(device, NULL, irb);
        }
        return TAPE_IO_SUCCESS;
}

/*
 * Basic Recovery routine
 */
static int
tape_3590_erp_basic(struct tape_device *device, struct tape_request *request,
                    struct irb *irb, int rc)
{
        struct tape_3590_sense *sense;

        sense = (struct tape_3590_sense *) irb->ecw;

        switch (sense->bra) {
        case SENSE_BRA_PER:
                return tape_3590_erp_failed(device, request, irb, rc);
        case SENSE_BRA_CONT:
                return tape_3590_erp_succeded(device, request);
        case SENSE_BRA_RE:
                return tape_3590_erp_retry(device, request, irb);
        case SENSE_BRA_DRE:
                return tape_3590_erp_failed(device, request, irb, rc);
        default:
                PRINT_ERR("Unknown BRA %x - This should not happen!\n",
                          sense->bra);
                BUG();
                return TAPE_IO_STOP;
        }
}

/*
 *  RDL: Read Device (buffered) log
 */
static int
tape_3590_erp_read_buf_log(struct tape_device *device,
                           struct tape_request *request, struct irb *irb)
{
        /*
         * We just do the basic error recovery at the moment (retry).
         * Perhaps in the future, we read the log and dump it somewhere...
         */
        return tape_3590_erp_basic(device, request, irb, -EIO);
}

/*
 *  SWAP: Swap Devices
 */
static int
tape_3590_erp_swap(struct tape_device *device, struct tape_request *request,
                   struct irb *irb)
{
        /*
         * This error recovery should swap the tapes
         * if the original has a problem. The operation
         * should proceed with the new tape... this
         * should probably be done in user space!
         */
        PRINT_WARN("(%s): Swap Tape Device!\n", device->cdev->dev.bus_id);
        return tape_3590_erp_basic(device, request, irb, -EIO);
}

/*
 *  LBY: Long Busy
 */
static int
tape_3590_erp_long_busy(struct tape_device *device,
                        struct tape_request *request, struct irb *irb)
{
        /* FIXME: how about WAITING for a minute ? */
        PRINT_WARN("(%s): Device is busy! Please wait a minute!\n",
                   device->cdev->dev.bus_id);
        return tape_3590_erp_basic(device, request, irb, -EBUSY);
}

/*
 *  SPI: Special Intercept
 */
static int
tape_3590_erp_special_interrupt(struct tape_device *device,
                                struct tape_request *request, struct irb *irb)
{
        return tape_3590_erp_basic(device, request, irb, -EIO);
}

/*
 *  RDA: Read Alternate
 */
static int
tape_3590_erp_read_alternate(struct tape_device *device,
                             struct tape_request *request, struct irb *irb)
{
        struct tape_3590_disc_data *data;

        /*
         * The issued Read Backward or Read Previous command is not
         * supported by the device
         * The recovery action should be to issue another command:
         * Read Revious: if Read Backward is not supported
         * Read Backward: if Read Previous is not supported
         */
        data = device->discdata;
        if (data->read_back_op == READ_PREVIOUS) {
                DBF_EVENT(2, "(%08x): No support for READ_PREVIOUS command\n",
                          device->cdev_id);
                data->read_back_op = READ_BACKWARD;
        } else {
                DBF_EVENT(2, "(%08x): No support for READ_BACKWARD command\n",
                          device->cdev_id);
                data->read_back_op = READ_PREVIOUS;
        }
        tape_3590_read_opposite(device, request);
        return tape_3590_erp_retry(device, request, irb);
}

/*
 * Error Recovery read opposite
 */
static int
tape_3590_erp_read_opposite(struct tape_device *device,
                            struct tape_request *request, struct irb *irb)
{
        switch (request->op) {
        case TO_RFO:
                /*
                 * We did read forward, but the data could not be read.
                 * We will read backward and then skip forward again.
                 */
                tape_3590_read_opposite(device, request);
                return tape_3590_erp_retry(device, request, irb);
        case TO_RBA:
                /* We tried to read forward and backward, but hat no success */
                return tape_3590_erp_failed(device, request, irb, -EIO);
                break;
        default:
                PRINT_WARN("read_opposite_recovery_called_with_op: %s\n",
                           tape_op_verbose[request->op]);
                return tape_3590_erp_failed(device, request, irb, -EIO);
        }
}

/*
 * Print an MIM (Media Information  Message) (message code f0)
 */
static void
tape_3590_print_mim_msg_f0(struct tape_device *device, struct irb *irb)
{
        struct tape_3590_sense *sense;

        sense = (struct tape_3590_sense *) irb->ecw;
        /* Exception Message */
        switch (sense->fmt.f70.emc) {
        case 0x02:
                PRINT_WARN("(%s): Data degraded\n", device->cdev->dev.bus_id);
                break;
        case 0x03:
                PRINT_WARN("(%s): Data degraded in partion %i\n",
                           device->cdev->dev.bus_id, sense->fmt.f70.mp);
                break;
        case 0x04:
                PRINT_WARN("(%s): Medium degraded\n", device->cdev->dev.bus_id);
                break;
        case 0x05:
                PRINT_WARN("(%s): Medium degraded in partition %i\n",
                           device->cdev->dev.bus_id, sense->fmt.f70.mp);
                break;
        case 0x06:
                PRINT_WARN("(%s): Block 0 Error\n", device->cdev->dev.bus_id);
                break;
        case 0x07:
                PRINT_WARN("(%s): Medium Exception 0x%02x\n",
                           device->cdev->dev.bus_id, sense->fmt.f70.md);
                break;
        default:
                PRINT_WARN("(%s): MIM ExMsg: 0x%02x\n",
                           device->cdev->dev.bus_id, sense->fmt.f70.emc);
                break;
        }
        /* Service Message */
        switch (sense->fmt.f70.smc) {
        case 0x02:
                PRINT_WARN("(%s): Reference Media maintenance procedure %i\n",
                           device->cdev->dev.bus_id, sense->fmt.f70.md);
                break;
        default:
                PRINT_WARN("(%s): MIM ServiceMsg: 0x%02x\n",
                           device->cdev->dev.bus_id, sense->fmt.f70.smc);
                break;
        }
}

/*
 * Print an I/O Subsystem Service Information Message (message code f1)
 */
static void
tape_3590_print_io_sim_msg_f1(struct tape_device *device, struct irb *irb)
{
        struct tape_3590_sense *sense;

        sense = (struct tape_3590_sense *) irb->ecw;
        /* Exception Message */
        switch (sense->fmt.f71.emc) {
        case 0x01:
                PRINT_WARN("(%s): Effect of failure is unknown\n",
                           device->cdev->dev.bus_id);
                break;
        case 0x02:
                PRINT_WARN("(%s): CU Exception - no performance impact\n",
                           device->cdev->dev.bus_id);
                break;
        case 0x03:
                PRINT_WARN("(%s): CU Exception on channel interface 0x%02x\n",
                           device->cdev->dev.bus_id, sense->fmt.f71.md[0]);
                break;
        case 0x04:
                PRINT_WARN("(%s): CU Exception on device path 0x%02x\n",
                           device->cdev->dev.bus_id, sense->fmt.f71.md[0]);
                break;
        case 0x05:
                PRINT_WARN("(%s): CU Exception on library path 0x%02x\n",
                           device->cdev->dev.bus_id, sense->fmt.f71.md[0]);
                break;
        case 0x06:
                PRINT_WARN("(%s): CU Exception on node 0x%02x\n",
                           device->cdev->dev.bus_id, sense->fmt.f71.md[0]);
                break;
        case 0x07:
                PRINT_WARN("(%s): CU Exception on partition 0x%02x\n",
                           device->cdev->dev.bus_id, sense->fmt.f71.md[0]);
                break;
        default:
                PRINT_WARN("(%s): SIM ExMsg: 0x%02x\n",
                           device->cdev->dev.bus_id, sense->fmt.f71.emc);
        }
        /* Service Message */
        switch (sense->fmt.f71.smc) {
        case 0x01:
                PRINT_WARN("(%s): Repair impact is unknown\n",
                           device->cdev->dev.bus_id);
                break;
        case 0x02:
                PRINT_WARN("(%s): Repair will not impact cu performance\n",
                           device->cdev->dev.bus_id);
                break;
        case 0x03:
                if (sense->fmt.f71.mdf == 0)
                        PRINT_WARN("(%s): Repair will disable node "
                                   "0x%x on CU\n",
                                   device->cdev->dev.bus_id,
                                   sense->fmt.f71.md[1]);
                else
                        PRINT_WARN("(%s): Repair will disable nodes "
                                   "(0x%x-0x%x) on CU\n",
                                   device->cdev->dev.bus_id,
                                   sense->fmt.f71.md[1], sense->fmt.f71.md[2]);
                break;
        case 0x04:
                if (sense->fmt.f71.mdf == 0)
                        PRINT_WARN("(%s): Repair will disable cannel path "
                                   "0x%x on CU\n",
                                   device->cdev->dev.bus_id,
                                   sense->fmt.f71.md[1]);
                else
                        PRINT_WARN("(%s): Repair will disable cannel paths "
                                   "(0x%x-0x%x) on CU\n",
                                   device->cdev->dev.bus_id,
                                   sense->fmt.f71.md[1], sense->fmt.f71.md[2]);
                break;
        case 0x05:
                if (sense->fmt.f71.mdf == 0)
                        PRINT_WARN("(%s): Repair will disable device path "
                                   "0x%x on CU\n",
                                   device->cdev->dev.bus_id,
                                   sense->fmt.f71.md[1]);
                else
                        PRINT_WARN("(%s): Repair will disable device paths "
                                   "(0x%x-0x%x) on CU\n",
                                   device->cdev->dev.bus_id,
                                   sense->fmt.f71.md[1], sense->fmt.f71.md[2]);
                break;
        case 0x06:
                if (sense->fmt.f71.mdf == 0)
                        PRINT_WARN("(%s): Repair will disable library path "
                                   "0x%x on CU\n",
                                   device->cdev->dev.bus_id,
                                   sense->fmt.f71.md[1]);
                else
                        PRINT_WARN("(%s): Repair will disable library paths "
                                   "(0x%x-0x%x) on CU\n",
                                   device->cdev->dev.bus_id,
                                   sense->fmt.f71.md[1], sense->fmt.f71.md[2]);
                break;
        case 0x07:
                PRINT_WARN("(%s): Repair will disable access to CU\n",
                           device->cdev->dev.bus_id);
                break;
        default:
                PRINT_WARN("(%s): SIM ServiceMsg: 0x%02x\n",
                           device->cdev->dev.bus_id, sense->fmt.f71.smc);
        }
}

/*
 * Print an Device Subsystem Service Information Message (message code f2)
 */
static void
tape_3590_print_dev_sim_msg_f2(struct tape_device *device, struct irb *irb)
{
        struct tape_3590_sense *sense;

        sense = (struct tape_3590_sense *) irb->ecw;
        /* Exception Message */
        switch (sense->fmt.f71.emc) {
        case 0x01:
                PRINT_WARN("(%s): Effect of failure is unknown\n",
                           device->cdev->dev.bus_id);
                break;
        case 0x02:
                PRINT_WARN("(%s): DV Exception - no performance impact\n",
                           device->cdev->dev.bus_id);
                break;
        case 0x03:
                PRINT_WARN("(%s): DV Exception on channel interface 0x%02x\n",
                           device->cdev->dev.bus_id, sense->fmt.f71.md[0]);
                break;
        case 0x04:
                PRINT_WARN("(%s): DV Exception on loader 0x%02x\n",
                           device->cdev->dev.bus_id, sense->fmt.f71.md[0]);
                break;
        case 0x05:
                PRINT_WARN("(%s): DV Exception on message display 0x%02x\n",
                           device->cdev->dev.bus_id, sense->fmt.f71.md[0]);
                break;
        case 0x06:
                PRINT_WARN("(%s): DV Exception in tape path\n",
                           device->cdev->dev.bus_id);
                break;
        case 0x07:
                PRINT_WARN("(%s): DV Exception in drive\n",
                           device->cdev->dev.bus_id);
                break;
        default:
                PRINT_WARN("(%s): DSIM ExMsg: 0x%02x\n",
                           device->cdev->dev.bus_id, sense->fmt.f71.emc);
        }
        /* Service Message */
        switch (sense->fmt.f71.smc) {
        case 0x01:
                PRINT_WARN("(%s): Repair impact is unknown\n",
                           device->cdev->dev.bus_id);
                break;
        case 0x02:
                PRINT_WARN("(%s): Repair will not impact device performance\n",
                           device->cdev->dev.bus_id);
                break;
        case 0x03:
                if (sense->fmt.f71.mdf == 0)
                        PRINT_WARN("(%s): Repair will disable channel path "
                                   "0x%x on DV\n",
                                   device->cdev->dev.bus_id,
                                   sense->fmt.f71.md[1]);
                else
                        PRINT_WARN("(%s): Repair will disable channel path "
                                   "(0x%x-0x%x) on DV\n",
                                   device->cdev->dev.bus_id,
                                   sense->fmt.f71.md[1], sense->fmt.f71.md[2]);
                break;
        case 0x04:
                if (sense->fmt.f71.mdf == 0)
                        PRINT_WARN("(%s): Repair will disable interface 0x%x "
                                   "on DV\n",
                                   device->cdev->dev.bus_id,
                                   sense->fmt.f71.md[1]);
                else
                        PRINT_WARN("(%s): Repair will disable interfaces "
                                   "(0x%x-0x%x) on DV\n",
                                   device->cdev->dev.bus_id,
                                   sense->fmt.f71.md[1], sense->fmt.f71.md[2]);
                break;
        case 0x05:
                if (sense->fmt.f71.mdf == 0)
                        PRINT_WARN("(%s): Repair will disable loader 0x%x "
                                   "on DV\n",
                                   device->cdev->dev.bus_id,
                                   sense->fmt.f71.md[1]);
                else
                        PRINT_WARN("(%s): Repair will disable loader "
                                   "(0x%x-0x%x) on DV\n",
                                   device->cdev->dev.bus_id,
                                   sense->fmt.f71.md[1], sense->fmt.f71.md[2]);
                break;
        case 0x07:
                PRINT_WARN("(%s): Repair will disable access to DV\n",
                           device->cdev->dev.bus_id);
                break;
        case 0x08:
                if (sense->fmt.f71.mdf == 0)
                        PRINT_WARN("(%s): Repair will disable message "
                                   "display 0x%x on DV\n",
                                   device->cdev->dev.bus_id,
                                   sense->fmt.f71.md[1]);
                else
                        PRINT_WARN("(%s): Repair will disable message "
                                   "displays (0x%x-0x%x) on DV\n",
                                   device->cdev->dev.bus_id,
                                   sense->fmt.f71.md[1], sense->fmt.f71.md[2]);
                break;
        case 0x09:
                PRINT_WARN("(%s): Clean DV\n", device->cdev->dev.bus_id);
                break;
        default:
                PRINT_WARN("(%s): DSIM ServiceMsg: 0x%02x\n",
                           device->cdev->dev.bus_id, sense->fmt.f71.smc);
        }
}

/*
 * Print standard ERA Message
 */
static void
tape_3590_print_era_msg(struct tape_device *device, struct irb *irb)
{
        struct tape_3590_sense *sense;

        sense = (struct tape_3590_sense *) irb->ecw;
        if (sense->mc == 0)
                return;
        if ((sense->mc > 0) && (sense->mc < TAPE_3590_MAX_MSG)) {
                if (tape_3590_msg[sense->mc] != NULL)
                        PRINT_WARN("(%s): %s\n", device->cdev->dev.bus_id,
                                   tape_3590_msg[sense->mc]);
                else {
                        PRINT_WARN("(%s): Message Code 0x%x\n",
                                   device->cdev->dev.bus_id, sense->mc);
                }
                return;
        }
        if (sense->mc == 0xf0) {
                /* Standard Media Information Message */
                PRINT_WARN("(%s): MIM SEV=%i, MC=%02x, ES=%x/%x, "
                           "RC=%02x-%04x-%02x\n", device->cdev->dev.bus_id,
                           sense->fmt.f70.sev, sense->mc,
                           sense->fmt.f70.emc, sense->fmt.f70.smc,
                           sense->fmt.f70.refcode, sense->fmt.f70.mid,
                           sense->fmt.f70.fid);
                tape_3590_print_mim_msg_f0(device, irb);
                return;
        }
        if (sense->mc == 0xf1) {
                /* Standard I/O Subsystem Service Information Message */
                PRINT_WARN("(%s): IOSIM SEV=%i, DEVTYPE=3590/%02x, "
                           "MC=%02x, ES=%x/%x, REF=0x%04x-0x%04x-0x%04x\n",
                           device->cdev->dev.bus_id, sense->fmt.f71.sev,
                           device->cdev->id.dev_model,
                           sense->mc, sense->fmt.f71.emc,
                           sense->fmt.f71.smc, sense->fmt.f71.refcode1,
                           sense->fmt.f71.refcode2, sense->fmt.f71.refcode3);
                tape_3590_print_io_sim_msg_f1(device, irb);
                return;
        }
        if (sense->mc == 0xf2) {
                /* Standard Device Service Information Message */
                PRINT_WARN("(%s): DEVSIM SEV=%i, DEVTYPE=3590/%02x, "
                           "MC=%02x, ES=%x/%x, REF=0x%04x-0x%04x-0x%04x\n",
                           device->cdev->dev.bus_id, sense->fmt.f71.sev,
                           device->cdev->id.dev_model,
                           sense->mc, sense->fmt.f71.emc,
                           sense->fmt.f71.smc, sense->fmt.f71.refcode1,
                           sense->fmt.f71.refcode2, sense->fmt.f71.refcode3);
                tape_3590_print_dev_sim_msg_f2(device, irb);
                return;
        }
        if (sense->mc == 0xf3) {
                /* Standard Library Service Information Message */
                return;
        }
        PRINT_WARN("(%s): Device Message(%x)\n",
                   device->cdev->dev.bus_id, sense->mc);
}

/*
 *  3590 error Recovery routine:
 *  If possible, it tries to recover from the error. If this is not possible,
 *  inform the user about the problem.
 */
static int
tape_3590_unit_check(struct tape_device *device, struct tape_request *request,
                     struct irb *irb)
{
        struct tape_3590_sense *sense;
        int rc;

#ifdef CONFIG_S390_TAPE_BLOCK
        if (request->op == TO_BLOCK) {
                /*
                 * Recovery for block device requests. Set the block_position
                 * to something invalid and retry.
                 */
                device->blk_data.block_position = -1;
                if (request->retries-- <= 0)
                        return tape_3590_erp_failed(device, request, irb, -EIO);
                else
                        return tape_3590_erp_retry(device, request, irb);
        }
#endif

        sense = (struct tape_3590_sense *) irb->ecw;

        /*
         * First check all RC-QRCs where we want to do something special
         *   - "break":     basic error recovery is done
         *   - "goto out:": just print error message if available
         */
        rc = -EIO;
        switch (sense->rc_rqc) {

        case 0x1110:
                tape_3590_print_era_msg(device, irb);
                return tape_3590_erp_read_buf_log(device, request, irb);

        case 0x2011:
                tape_3590_print_era_msg(device, irb);
                return tape_3590_erp_read_alternate(device, request, irb);

        case 0x2230:
        case 0x2231:
                tape_3590_print_era_msg(device, irb);
                return tape_3590_erp_special_interrupt(device, request, irb);

        case 0x3010:
                DBF_EVENT(2, "(%08x): Backward at Beginning of Partition\n",
                          device->cdev_id);
                return tape_3590_erp_basic(device, request, irb, -ENOSPC);
        case 0x3012:
                DBF_EVENT(2, "(%08x): Forward at End of Partition\n",
                          device->cdev_id);
                return tape_3590_erp_basic(device, request, irb, -ENOSPC);
        case 0x3020:
                DBF_EVENT(2, "(%08x): End of Data Mark\n", device->cdev_id);
                return tape_3590_erp_basic(device, request, irb, -ENOSPC);

        case 0x3122:
                DBF_EVENT(2, "(%08x): Rewind Unload initiated\n",
                          device->cdev_id);
                return tape_3590_erp_basic(device, request, irb, -EIO);
        case 0x3123:
                DBF_EVENT(2, "(%08x): Rewind Unload complete\n",
                          device->cdev_id);
                tape_med_state_set(device, MS_UNLOADED);
                return tape_3590_erp_basic(device, request, irb, 0);

        case 0x4010:
                /*
                 * print additional msg since default msg
                 * "device intervention" is not very meaningfull
                 */
                PRINT_WARN("(%s): Tape operation when medium not loaded\n",
                           device->cdev->dev.bus_id);
                tape_med_state_set(device, MS_UNLOADED);
                return tape_3590_erp_basic(device, request, irb, -ENOMEDIUM);
        case 0x4012:            /* Device Long Busy */
                tape_3590_print_era_msg(device, irb);
                return tape_3590_erp_long_busy(device, request, irb);

        case 0x5010:
                if (sense->rac == 0xd0) {
                        /* Swap */
                        tape_3590_print_era_msg(device, irb);
                        return tape_3590_erp_swap(device, request, irb);
                }
                if (sense->rac == 0x26) {
                        /* Read Opposite */
                        tape_3590_print_era_msg(device, irb);
                        return tape_3590_erp_read_opposite(device, request,
                                                           irb);
                }
                return tape_3590_erp_basic(device, request, irb, -EIO);
        case 0x5020:
        case 0x5021:
        case 0x5022:
        case 0x5040:
        case 0x5041:
        case 0x5042:
                tape_3590_print_era_msg(device, irb);
                return tape_3590_erp_swap(device, request, irb);

        case 0x5110:
        case 0x5111:
                return tape_3590_erp_basic(device, request, irb, -EMEDIUMTYPE);

        case 0x5120:
        case 0x1120:
                tape_med_state_set(device, MS_UNLOADED);
                return tape_3590_erp_basic(device, request, irb, -ENOMEDIUM);

        case 0x6020:
                PRINT_WARN("(%s): Cartridge of wrong type ?\n",
                           device->cdev->dev.bus_id);
                return tape_3590_erp_basic(device, request, irb, -EMEDIUMTYPE);

        case 0x8011:
                PRINT_WARN("(%s): Another host has reserved the tape device\n",
                           device->cdev->dev.bus_id);
                return tape_3590_erp_basic(device, request, irb, -EPERM);
        case 0x8013:
                PRINT_WARN("(%s): Another host has priviliged access to the "
                           "tape device\n", device->cdev->dev.bus_id);
                PRINT_WARN("(%s): To solve the problem unload the current "
                           "cartridge!\n", device->cdev->dev.bus_id);
                return tape_3590_erp_basic(device, request, irb, -EPERM);
        default:
                return tape_3590_erp_basic(device, request, irb, -EIO);
        }
}

/*
 * 3590 interrupt handler:
 */
static int
tape_3590_irq(struct tape_device *device, struct tape_request *request,
              struct irb *irb)
{
        if (request == NULL)
                return tape_3590_unsolicited_irq(device, irb);

        if ((irb->scsw.dstat & DEV_STAT_UNIT_EXCEP) &&
            (irb->scsw.dstat & DEV_STAT_DEV_END) && (request->op == TO_WRI)) {
                /* Write at end of volume */
                DBF_EVENT(2, "End of volume\n");
                return tape_3590_erp_failed(device, request, irb, -ENOSPC);
        }

        if (irb->scsw.dstat & DEV_STAT_UNIT_CHECK)
                return tape_3590_unit_check(device, request, irb);

        if (irb->scsw.dstat & DEV_STAT_DEV_END) {
                if (irb->scsw.dstat == DEV_STAT_UNIT_EXCEP) {
                        if (request->op == TO_FSB || request->op == TO_BSB)
                                request->rescnt++;
                        else
                                DBF_EVENT(5, "Unit Exception!\n");
                }

                return tape_3590_done(device, request);
        }

        if (irb->scsw.dstat & DEV_STAT_CHN_END) {
                DBF_EVENT(2, "cannel end\n");
                return TAPE_IO_PENDING;
        }

        if (irb->scsw.dstat & DEV_STAT_ATTENTION) {
                DBF_EVENT(2, "Unit Attention when busy..\n");
                return TAPE_IO_PENDING;
        }

        DBF_EVENT(6, "xunknownirq\n");
        PRINT_ERR("Unexpected interrupt.\n");
        PRINT_ERR("Current op is: %s", tape_op_verbose[request->op]);
        tape_dump_sense(device, request, irb);
        return TAPE_IO_STOP;
}

/*
 * Setup device function
 */
static int
tape_3590_setup_device(struct tape_device *device)
{
        int rc;
        struct tape_3590_disc_data *data;

        DBF_EVENT(6, "3590 device setup\n");
        data = kmalloc(sizeof(struct tape_3590_disc_data),
                       GFP_KERNEL | GFP_DMA);
        if (data == NULL)
                return -ENOMEM;
        data->read_back_op = READ_PREVIOUS;
        device->discdata = data;

        if ((rc = tape_std_assign(device)) == 0) {
                /* Try to find out if medium is loaded */
                if ((rc = tape_3590_sense_medium(device)) != 0)
                        DBF_LH(3, "3590 medium sense returned %d\n", rc);
        }

        return rc;
}

/*
 * Cleanup device function
 */
static void
tape_3590_cleanup_device(struct tape_device *device)
{
        flush_scheduled_work();
        tape_std_unassign(device);

        kfree(device->discdata);
        device->discdata = NULL;
}

/*
 * List of 3590 magnetic tape commands.
 */
static tape_mtop_fn tape_3590_mtop[TAPE_NR_MTOPS] = {
        [MTRESET]        = tape_std_mtreset,
        [MTFSF]          = tape_std_mtfsf,
        [MTBSF]          = tape_std_mtbsf,
        [MTFSR]          = tape_std_mtfsr,
        [MTBSR]          = tape_std_mtbsr,
        [MTWEOF]         = tape_std_mtweof,
        [MTREW]          = tape_std_mtrew,
        [MTOFFL]         = tape_std_mtoffl,
        [MTNOP]          = tape_std_mtnop,
        [MTRETEN]        = tape_std_mtreten,
        [MTBSFM]         = tape_std_mtbsfm,
        [MTFSFM]         = tape_std_mtfsfm,
        [MTEOM]          = tape_std_mteom,
        [MTERASE]        = tape_std_mterase,
        [MTRAS1]         = NULL,
        [MTRAS2]         = NULL,
        [MTRAS3]         = NULL,
        [MTSETBLK]       = tape_std_mtsetblk,
        [MTSETDENSITY]   = NULL,
        [MTSEEK]         = tape_3590_mtseek,
        [MTTELL]         = tape_3590_mttell,
        [MTSETDRVBUFFER] = NULL,
        [MTFSS]          = NULL,
        [MTBSS]          = NULL,
        [MTWSM]          = NULL,
        [MTLOCK]         = NULL,
        [MTUNLOCK]       = NULL,
        [MTLOAD]         = tape_std_mtload,
        [MTUNLOAD]       = tape_std_mtunload,
        [MTCOMPRESSION]  = tape_std_mtcompression,
        [MTSETPART]      = NULL,
        [MTMKPART]       = NULL
};

/*
 * Tape discipline structure for 3590.
 */
static struct tape_discipline tape_discipline_3590 = {
        .owner = THIS_MODULE,
        .setup_device = tape_3590_setup_device,
        .cleanup_device = tape_3590_cleanup_device,
        .process_eov = tape_std_process_eov,
        .irq = tape_3590_irq,
        .read_block = tape_std_read_block,
        .write_block = tape_std_write_block,
#ifdef CONFIG_S390_TAPE_BLOCK
        .bread = tape_3590_bread,
        .free_bread = tape_3590_free_bread,
        .check_locate = tape_3590_check_locate,
#endif
        .ioctl_fn = tape_3590_ioctl,
        .mtop_array = tape_3590_mtop
};

static struct ccw_device_id tape_3590_ids[] = {
        {CCW_DEVICE_DEVTYPE(0x3590, 0, 0x3590, 0), .driver_info = tape_3590},
        {CCW_DEVICE_DEVTYPE(0x3592, 0, 0x3592, 0), .driver_info = tape_3592},
        { /* end of list */ }
};

static int
tape_3590_online(struct ccw_device *cdev)
{
        return tape_generic_online(cdev->dev.driver_data,
                                   &tape_discipline_3590);
}

static int
tape_3590_offline(struct ccw_device *cdev)
{
        return tape_generic_offline(cdev->dev.driver_data);
}

static struct ccw_driver tape_3590_driver = {
        .name = "tape_3590",
        .owner = THIS_MODULE,
        .ids = tape_3590_ids,
        .probe = tape_generic_probe,
        .remove = tape_generic_remove,
        .set_offline = tape_3590_offline,
        .set_online = tape_3590_online,
};

/*
 * Setup discipline structure.
 */
static int
tape_3590_init(void)
{
        int rc;

        TAPE_DBF_AREA = debug_register("tape_3590", 2, 2, 4 * sizeof(long));
        debug_register_view(TAPE_DBF_AREA, &debug_sprintf_view);
#ifdef DBF_LIKE_HELL
        debug_set_level(TAPE_DBF_AREA, 6);
#endif

        DBF_EVENT(3, "3590 init\n");
        /* Register driver for 3590 tapes. */
        rc = ccw_driver_register(&tape_3590_driver);
        if (rc)
                DBF_EVENT(3, "3590 init failed\n");
        else
                DBF_EVENT(3, "3590 registered\n");
        return rc;
}

static void
tape_3590_exit(void)
{
        ccw_driver_unregister(&tape_3590_driver);

        debug_unregister(TAPE_DBF_AREA);
}

MODULE_DEVICE_TABLE(ccw, tape_3590_ids);
MODULE_AUTHOR("(C) 2001,2006 IBM Corporation");
MODULE_DESCRIPTION("Linux on zSeries channel attached 3590 tape device driver");
MODULE_LICENSE("GPL");

module_init(tape_3590_init);
module_exit(tape_3590_exit);