tape_std.c

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/*
 *    standard tape device functions for ibm tapes.
 *
 *  S390 and zSeries version
 *    Copyright IBM Corp. 2001, 2002
 *    Author(s): Carsten Otte <[email protected]>
 *       Michael Holzheu <[email protected]>
 *       Tuan Ngo-Anh <[email protected]>
 *       Martin Schwidefsky <[email protected]>
 *       Stefan Bader <[email protected]>
 */

#define KMSG_COMPONENT "tape"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt

#include <linux/stddef.h>
#include <linux/kernel.h>
#include <linux/bio.h>
#include <linux/timer.h>

#include <asm/types.h>
#include <asm/idals.h>
#include <asm/ebcdic.h>
#include <asm/tape390.h>

#define TAPE_DBF_AREA   tape_core_dbf

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

/*
 * tape_std_assign
 */
static void
tape_std_assign_timeout(unsigned long data)
{
    struct tape_request *   request;
    struct tape_device *    device;
    int rc;

    request = (struct tape_request *) data;
    device = request->device;
    BUG_ON(!device);

    DBF_EVENT(3, "%08x: Assignment timeout. Device busy.\n",
            device->cdev_id);
    rc = tape_cancel_io(device, request);
    if(rc)
        DBF_EVENT(3, "(%08x): Assign timeout: Cancel failed with rc = "
              "%i\n", device->cdev_id, rc);
}

int
tape_std_assign(struct tape_device *device)
{
    int                  rc;
    struct timer_list    timeout;
    struct tape_request *request;

    request = tape_alloc_request(2, 11);
    if (IS_ERR(request))
        return PTR_ERR(request);

    request->op = TO_ASSIGN;
    tape_ccw_cc(request->cpaddr, ASSIGN, 11, request->cpdata);
    tape_ccw_end(request->cpaddr + 1, NOP, 0, NULL);

    /*
     * The assign command sometimes blocks if the device is assigned
     * to another host (actually this shouldn't happen but it does).
     * So we set up a timeout for this call.
     */
    init_timer_on_stack(&timeout);
    timeout.function = tape_std_assign_timeout;
    timeout.data     = (unsigned long) request;
    timeout.expires  = jiffies + 2 * HZ;
    add_timer(&timeout);

    rc = tape_do_io_interruptible(device, request);

    del_timer(&timeout);

    if (rc != 0) {
        DBF_EVENT(3, "%08x: assign failed - device might be busy\n",
            device->cdev_id);
    } else {
        DBF_EVENT(3, "%08x: Tape assigned\n", device->cdev_id);
    }
    tape_free_request(request);
    return rc;
}

/*
 * tape_std_unassign
 */
int
tape_std_unassign (struct tape_device *device)
{
    int                  rc;
    struct tape_request *request;

    if (device->tape_state == TS_NOT_OPER) {
        DBF_EVENT(3, "(%08x): Can't unassign device\n",
            device->cdev_id);
        return -EIO;
    }

    request = tape_alloc_request(2, 11);
    if (IS_ERR(request))
        return PTR_ERR(request);

    request->op = TO_UNASSIGN;
    tape_ccw_cc(request->cpaddr, UNASSIGN, 11, request->cpdata);
    tape_ccw_end(request->cpaddr + 1, NOP, 0, NULL);

    if ((rc = tape_do_io(device, request)) != 0) {
        DBF_EVENT(3, "%08x: Unassign failed\n", device->cdev_id);
    } else {
        DBF_EVENT(3, "%08x: Tape unassigned\n", device->cdev_id);
    }
    tape_free_request(request);
    return rc;
}

/*
 * TAPE390_DISPLAY: Show a string on the tape display.
 */
int
tape_std_display(struct tape_device *device, struct display_struct *disp)
{
    struct tape_request *request;
    int rc;

    request = tape_alloc_request(2, 17);
    if (IS_ERR(request)) {
        DBF_EVENT(3, "TAPE: load display failed\n");
        return PTR_ERR(request);
    }
    request->op = TO_DIS;

    *(unsigned char *) request->cpdata = disp->cntrl;
    DBF_EVENT(5, "TAPE: display cntrl=%04x\n", disp->cntrl);
    memcpy(((unsigned char *) request->cpdata) + 1, disp->message1, 8);
    memcpy(((unsigned char *) request->cpdata) + 9, disp->message2, 8);
    ASCEBC(((unsigned char*) request->cpdata) + 1, 16);

    tape_ccw_cc(request->cpaddr, LOAD_DISPLAY, 17, request->cpdata);
    tape_ccw_end(request->cpaddr + 1, NOP, 0, NULL);

    rc = tape_do_io_interruptible(device, request);
    tape_free_request(request);
    return rc;
}

/*
 * Read block id.
 */
int
tape_std_read_block_id(struct tape_device *device, __u64 *id)
{
    struct tape_request *request;
    int rc;

    request = tape_alloc_request(3, 8);
    if (IS_ERR(request))
        return PTR_ERR(request);
    request->op = TO_RBI;
    /* setup ccws */
    tape_ccw_cc(request->cpaddr, MODE_SET_DB, 1, device->modeset_byte);
    tape_ccw_cc(request->cpaddr + 1, READ_BLOCK_ID, 8, request->cpdata);
    tape_ccw_end(request->cpaddr + 2, NOP, 0, NULL);
    /* execute it */
    rc = tape_do_io(device, request);
    if (rc == 0)
        /* Get result from read buffer. */
        *id = *(__u64 *) request->cpdata;
    tape_free_request(request);
    return rc;
}

int
tape_std_terminate_write(struct tape_device *device)
{
    int rc;

    if(device->required_tapemarks == 0)
        return 0;

    DBF_LH(5, "tape%d: terminate write %dxEOF\n", device->first_minor,
        device->required_tapemarks);

    rc = tape_mtop(device, MTWEOF, device->required_tapemarks);
    if (rc)
        return rc;

    device->required_tapemarks = 0;
    return tape_mtop(device, MTBSR, 1);
}

/*
 * MTLOAD: Loads the tape.
 * The default implementation just wait until the tape medium state changes
 * to MS_LOADED.
 */
int
tape_std_mtload(struct tape_device *device, int count)
{
    return wait_event_interruptible(device->state_change_wq,
        (device->medium_state == MS_LOADED));
}

/*
 * MTSETBLK: Set block size.
 */
int
tape_std_mtsetblk(struct tape_device *device, int count)
{
    struct idal_buffer *new;

    DBF_LH(6, "tape_std_mtsetblk(%d)\n", count);
    if (count <= 0) {
        /*
         * Just set block_size to 0. tapechar_read/tapechar_write
         * will realloc the idal buffer if a bigger one than the
         * current is needed.
         */
        device->char_data.block_size = 0;
        return 0;
    }
    if (device->char_data.idal_buf != NULL &&
        device->char_data.idal_buf->size == count)
        /* We already have a idal buffer of that size. */
        return 0;

    if (count > MAX_BLOCKSIZE) {
        DBF_EVENT(3, "Invalid block size (%d > %d) given.\n",
            count, MAX_BLOCKSIZE);
        return -EINVAL;
    }

    /* Allocate a new idal buffer. */
    new = idal_buffer_alloc(count, 0);
    if (IS_ERR(new))
        return -ENOMEM;
    if (device->char_data.idal_buf != NULL)
        idal_buffer_free(device->char_data.idal_buf);
    device->char_data.idal_buf = new;
    device->char_data.block_size = count;

    DBF_LH(6, "new blocksize is %d\n", device->char_data.block_size);

    return 0;
}

/*
 * MTRESET: Set block size to 0.
 */
int
tape_std_mtreset(struct tape_device *device, int count)
{
    DBF_EVENT(6, "TCHAR:devreset:\n");
    device->char_data.block_size = 0;
    return 0;
}

/*
 * MTFSF: Forward space over 'count' file marks. The tape is positioned
 * at the EOT (End of Tape) side of the file mark.
 */
int
tape_std_mtfsf(struct tape_device *device, int mt_count)
{
    struct tape_request *request;
    struct ccw1 *ccw;

    request = tape_alloc_request(mt_count + 2, 0);
    if (IS_ERR(request))
        return PTR_ERR(request);
    request->op = TO_FSF;
    /* setup ccws */
    ccw = tape_ccw_cc(request->cpaddr, MODE_SET_DB, 1,
              device->modeset_byte);
    ccw = tape_ccw_repeat(ccw, FORSPACEFILE, mt_count);
    ccw = tape_ccw_end(ccw, NOP, 0, NULL);

    /* execute it */
    return tape_do_io_free(device, request);
}

/*
 * MTFSR: Forward space over 'count' tape blocks (blocksize is set
 * via MTSETBLK.
 */
int
tape_std_mtfsr(struct tape_device *device, int mt_count)
{
    struct tape_request *request;
    struct ccw1 *ccw;
    int rc;

    request = tape_alloc_request(mt_count + 2, 0);
    if (IS_ERR(request))
        return PTR_ERR(request);
    request->op = TO_FSB;
    /* setup ccws */
    ccw = tape_ccw_cc(request->cpaddr, MODE_SET_DB, 1,
              device->modeset_byte);
    ccw = tape_ccw_repeat(ccw, FORSPACEBLOCK, mt_count);
    ccw = tape_ccw_end(ccw, NOP, 0, NULL);

    /* execute it */
    rc = tape_do_io(device, request);
    if (rc == 0 && request->rescnt > 0) {
        DBF_LH(3, "FSR over tapemark\n");
        rc = 1;
    }
    tape_free_request(request);

    return rc;
}

/*
 * MTBSR: Backward space over 'count' tape blocks.
 * (blocksize is set via MTSETBLK.
 */
int
tape_std_mtbsr(struct tape_device *device, int mt_count)
{
    struct tape_request *request;
    struct ccw1 *ccw;
    int rc;

    request = tape_alloc_request(mt_count + 2, 0);
    if (IS_ERR(request))
        return PTR_ERR(request);
    request->op = TO_BSB;
    /* setup ccws */
    ccw = tape_ccw_cc(request->cpaddr, MODE_SET_DB, 1,
              device->modeset_byte);
    ccw = tape_ccw_repeat(ccw, BACKSPACEBLOCK, mt_count);
    ccw = tape_ccw_end(ccw, NOP, 0, NULL);

    /* execute it */
    rc = tape_do_io(device, request);
    if (rc == 0 && request->rescnt > 0) {
        DBF_LH(3, "BSR over tapemark\n");
        rc = 1;
    }
    tape_free_request(request);

    return rc;
}

/*
 * MTWEOF: Write 'count' file marks at the current position.
 */
int
tape_std_mtweof(struct tape_device *device, int mt_count)
{
    struct tape_request *request;
    struct ccw1 *ccw;

    request = tape_alloc_request(mt_count + 2, 0);
    if (IS_ERR(request))
        return PTR_ERR(request);
    request->op = TO_WTM;
    /* setup ccws */
    ccw = tape_ccw_cc(request->cpaddr, MODE_SET_DB, 1,
              device->modeset_byte);
    ccw = tape_ccw_repeat(ccw, WRITETAPEMARK, mt_count);
    ccw = tape_ccw_end(ccw, NOP, 0, NULL);

    /* execute it */
    return tape_do_io_free(device, request);
}

/*
 * MTBSFM: Backward space over 'count' file marks.
 * The tape is positioned at the BOT (Begin Of Tape) side of the
 * last skipped file mark.
 */
int
tape_std_mtbsfm(struct tape_device *device, int mt_count)
{
    struct tape_request *request;
    struct ccw1 *ccw;

    request = tape_alloc_request(mt_count + 2, 0);
    if (IS_ERR(request))
        return PTR_ERR(request);
    request->op = TO_BSF;
    /* setup ccws */
    ccw = tape_ccw_cc(request->cpaddr, MODE_SET_DB, 1,
              device->modeset_byte);
    ccw = tape_ccw_repeat(ccw, BACKSPACEFILE, mt_count);
    ccw = tape_ccw_end(ccw, NOP, 0, NULL);

    /* execute it */
    return tape_do_io_free(device, request);
}

/*
 * MTBSF: Backward space over 'count' file marks. The tape is positioned at
 * the EOT (End of Tape) side of the last skipped file mark.
 */
int
tape_std_mtbsf(struct tape_device *device, int mt_count)
{
    struct tape_request *request;
    struct ccw1 *ccw;
    int rc;

    request = tape_alloc_request(mt_count + 2, 0);
    if (IS_ERR(request))
        return PTR_ERR(request);
    request->op = TO_BSF;
    /* setup ccws */
    ccw = tape_ccw_cc(request->cpaddr, MODE_SET_DB, 1,
              device->modeset_byte);
    ccw = tape_ccw_repeat(ccw, BACKSPACEFILE, mt_count);
    ccw = tape_ccw_end(ccw, NOP, 0, NULL);
    /* execute it */
    rc = tape_do_io_free(device, request);
    if (rc == 0) {
        rc = tape_mtop(device, MTFSR, 1);
        if (rc > 0)
            rc = 0;
    }
    return rc;
}

/*
 * MTFSFM: Forward space over 'count' file marks.
 * The tape is positioned at the BOT (Begin Of Tape) side
 * of the last skipped file mark.
 */
int
tape_std_mtfsfm(struct tape_device *device, int mt_count)
{
    struct tape_request *request;
    struct ccw1 *ccw;
    int rc;

    request = tape_alloc_request(mt_count + 2, 0);
    if (IS_ERR(request))
        return PTR_ERR(request);
    request->op = TO_FSF;
    /* setup ccws */
    ccw = tape_ccw_cc(request->cpaddr, MODE_SET_DB, 1,
              device->modeset_byte);
    ccw = tape_ccw_repeat(ccw, FORSPACEFILE, mt_count);
    ccw = tape_ccw_end(ccw, NOP, 0, NULL);
    /* execute it */
    rc = tape_do_io_free(device, request);
    if (rc == 0) {
        rc = tape_mtop(device, MTBSR, 1);
        if (rc > 0)
            rc = 0;
    }

    return rc;
}

/*
 * MTREW: Rewind the tape.
 */
int
tape_std_mtrew(struct tape_device *device, int mt_count)
{
    struct tape_request *request;

    request = tape_alloc_request(3, 0);
    if (IS_ERR(request))
        return PTR_ERR(request);
    request->op = TO_REW;
    /* setup ccws */
    tape_ccw_cc(request->cpaddr, MODE_SET_DB, 1,
            device->modeset_byte);
    tape_ccw_cc(request->cpaddr + 1, REWIND, 0, NULL);
    tape_ccw_end(request->cpaddr + 2, NOP, 0, NULL);

    /* execute it */
    return tape_do_io_free(device, request);
}

/*
 * MTOFFL: Rewind the tape and put the drive off-line.
 * Implement 'rewind unload'
 */
int
tape_std_mtoffl(struct tape_device *device, int mt_count)
{
    struct tape_request *request;

    request = tape_alloc_request(3, 0);
    if (IS_ERR(request))
        return PTR_ERR(request);
    request->op = TO_RUN;
    /* setup ccws */
    tape_ccw_cc(request->cpaddr, MODE_SET_DB, 1, device->modeset_byte);
    tape_ccw_cc(request->cpaddr + 1, REWIND_UNLOAD, 0, NULL);
    tape_ccw_end(request->cpaddr + 2, NOP, 0, NULL);

    /* execute it */
    return tape_do_io_free(device, request);
}

/*
 * MTNOP: 'No operation'.
 */
int
tape_std_mtnop(struct tape_device *device, int mt_count)
{
    struct tape_request *request;

    request = tape_alloc_request(2, 0);
    if (IS_ERR(request))
        return PTR_ERR(request);
    request->op = TO_NOP;
    /* setup ccws */
    tape_ccw_cc(request->cpaddr, MODE_SET_DB, 1, device->modeset_byte);
    tape_ccw_end(request->cpaddr + 1, NOP, 0, NULL);
    /* execute it */
    return tape_do_io_free(device, request);
}

/*
 * MTEOM: positions at the end of the portion of the tape already used
 * for recordind data. MTEOM positions after the last file mark, ready for
 * appending another file.
 */
int
tape_std_mteom(struct tape_device *device, int mt_count)
{
    int rc;

    /*
     * Seek from the beginning of tape (rewind).
     */
    if ((rc = tape_mtop(device, MTREW, 1)) < 0)
        return rc;

    /*
     * The logical end of volume is given by two sewuential tapemarks.
     * Look for this by skipping to the next file (over one tapemark)
     * and then test for another one (fsr returns 1 if a tapemark was
     * encountered).
     */
    do {
        if ((rc = tape_mtop(device, MTFSF, 1)) < 0)
            return rc;
        if ((rc = tape_mtop(device, MTFSR, 1)) < 0)
            return rc;
    } while (rc == 0);

    return tape_mtop(device, MTBSR, 1);
}

/*
 * MTRETEN: Retension the tape, i.e. forward space to end of tape and rewind.
 */
int
tape_std_mtreten(struct tape_device *device, int mt_count)
{
    struct tape_request *request;

    request = tape_alloc_request(4, 0);
    if (IS_ERR(request))
        return PTR_ERR(request);
    request->op = TO_FSF;
    /* setup ccws */
    tape_ccw_cc(request->cpaddr, MODE_SET_DB, 1, device->modeset_byte);
    tape_ccw_cc(request->cpaddr + 1,FORSPACEFILE, 0, NULL);
    tape_ccw_cc(request->cpaddr + 2, NOP, 0, NULL);
    tape_ccw_end(request->cpaddr + 3, CCW_CMD_TIC, 0, request->cpaddr);
    /* execute it, MTRETEN rc gets ignored */
    tape_do_io_interruptible(device, request);
    tape_free_request(request);
    return tape_mtop(device, MTREW, 1);
}

/*
 * MTERASE: erases the tape.
 */
int
tape_std_mterase(struct tape_device *device, int mt_count)
{
    struct tape_request *request;

    request = tape_alloc_request(6, 0);
    if (IS_ERR(request))
        return PTR_ERR(request);
    request->op = TO_DSE;
    /* setup ccws */
    tape_ccw_cc(request->cpaddr, MODE_SET_DB, 1, device->modeset_byte);
    tape_ccw_cc(request->cpaddr + 1, REWIND, 0, NULL);
    tape_ccw_cc(request->cpaddr + 2, ERASE_GAP, 0, NULL);
    tape_ccw_cc(request->cpaddr + 3, DATA_SEC_ERASE, 0, NULL);
    tape_ccw_cc(request->cpaddr + 4, REWIND, 0, NULL);
    tape_ccw_end(request->cpaddr + 5, NOP, 0, NULL);

    /* execute it */
    return tape_do_io_free(device, request);
}

/*
 * MTUNLOAD: Rewind the tape and unload it.
 */
int
tape_std_mtunload(struct tape_device *device, int mt_count)
{
    return tape_mtop(device, MTOFFL, mt_count);
}

/*
 * MTCOMPRESSION: used to enable compression.
 * Sets the IDRC on/off.
 */
int
tape_std_mtcompression(struct tape_device *device, int mt_count)
{
    struct tape_request *request;

    if (mt_count < 0 || mt_count > 1) {
        DBF_EXCEPTION(6, "xcom parm\n");
        return -EINVAL;
    }
    request = tape_alloc_request(2, 0);
    if (IS_ERR(request))
        return PTR_ERR(request);
    request->op = TO_NOP;
    /* setup ccws */
    if (mt_count == 0)
        *device->modeset_byte &= ~0x08;
    else
        *device->modeset_byte |= 0x08;
    tape_ccw_cc(request->cpaddr, MODE_SET_DB, 1, device->modeset_byte);
    tape_ccw_end(request->cpaddr + 1, NOP, 0, NULL);
    /* execute it */
    return tape_do_io_free(device, request);
}

/*
 * Read Block
 */
struct tape_request *
tape_std_read_block(struct tape_device *device, size_t count)
{
    struct tape_request *request;

    /*
     * We have to alloc 4 ccws in order to be able to transform request
     * into a read backward request in error case.
     */
    request = tape_alloc_request(4, 0);
    if (IS_ERR(request)) {
        DBF_EXCEPTION(6, "xrbl fail");
        return request;
    }
    request->op = TO_RFO;
    tape_ccw_cc(request->cpaddr, MODE_SET_DB, 1, device->modeset_byte);
    tape_ccw_end_idal(request->cpaddr + 1, READ_FORWARD,
              device->char_data.idal_buf);
    DBF_EVENT(6, "xrbl ccwg\n");
    return request;
}

/*
 * Read Block backward transformation function.
 */
void
tape_std_read_backward(struct tape_device *device, struct tape_request *request)
{
    /*
     * 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);
    tape_ccw_cc_idal(request->cpaddr + 1, READ_BACKWARD,
             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");}

/*
 * Write Block
 */
struct tape_request *
tape_std_write_block(struct tape_device *device, size_t count)
{
    struct tape_request *request;

    request = tape_alloc_request(2, 0);
    if (IS_ERR(request)) {
        DBF_EXCEPTION(6, "xwbl fail\n");
        return request;
    }
    request->op = TO_WRI;
    tape_ccw_cc(request->cpaddr, MODE_SET_DB, 1, device->modeset_byte);
    tape_ccw_end_idal(request->cpaddr + 1, WRITE_CMD,
              device->char_data.idal_buf);
    DBF_EVENT(6, "xwbl ccwg\n");
    return request;
}

/*
 * This routine is called by frontend after an ENOSP on write
 */
void
tape_std_process_eov(struct tape_device *device)
{
    /*
     * End of volume: We have to backspace the last written record, then
     * we TRY to write a tapemark and then backspace over the written TM
     */
    if (tape_mtop(device, MTBSR, 1) == 0 &&
        tape_mtop(device, MTWEOF, 1) == 0) {
        tape_mtop(device, MTBSR, 1);
    }
}

EXPORT_SYMBOL(tape_std_assign);
EXPORT_SYMBOL(tape_std_unassign);
EXPORT_SYMBOL(tape_std_display);
EXPORT_SYMBOL(tape_std_read_block_id);
EXPORT_SYMBOL(tape_std_mtload);
EXPORT_SYMBOL(tape_std_mtsetblk);
EXPORT_SYMBOL(tape_std_mtreset);
EXPORT_SYMBOL(tape_std_mtfsf);
EXPORT_SYMBOL(tape_std_mtfsr);
EXPORT_SYMBOL(tape_std_mtbsr);
EXPORT_SYMBOL(tape_std_mtweof);
EXPORT_SYMBOL(tape_std_mtbsfm);
EXPORT_SYMBOL(tape_std_mtbsf);
EXPORT_SYMBOL(tape_std_mtfsfm);
EXPORT_SYMBOL(tape_std_mtrew);
EXPORT_SYMBOL(tape_std_mtoffl);
EXPORT_SYMBOL(tape_std_mtnop);
EXPORT_SYMBOL(tape_std_mteom);
EXPORT_SYMBOL(tape_std_mtreten);
EXPORT_SYMBOL(tape_std_mterase);
EXPORT_SYMBOL(tape_std_mtunload);
EXPORT_SYMBOL(tape_std_mtcompression);
EXPORT_SYMBOL(tape_std_read_block);
EXPORT_SYMBOL(tape_std_read_backward);
EXPORT_SYMBOL(tape_std_write_block);
EXPORT_SYMBOL(tape_std_process_eov);