tape_3590.c

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	case TAPE390_CRYPT_SET:
		return tape_3592_ioctl_crypt_set(device, arg);
	case TAPE390_CRYPT_QUERY:
		return tape_3592_ioctl_crypt_query(device, arg);
	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(struct work_struct *work)
{
	struct work_handler_data *p =
		container_of(work, struct work_handler_data, work);

	switch (p->op) {
	case TO_MSEN:
		tape_3590_sense_medium(p->device);
		break;
	case TO_READ_ATTMSG:
		tape_3590_read_attmsg(p->device);
		break;
	case TO_CRYPT_ON:
		tape_3592_enable_crypt(p->device);
		break;
	case TO_CRYPT_OFF:
		tape_3592_disable_crypt(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->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;
	unsigned off;
	char *dst;
	struct bio_vec *bv;
	struct req_iterator iter;

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

	rq_for_each_segment(bv, req, iter)
		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_segment(bv, req, iter) {
		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

static void tape_3590_med_state_set(struct tape_device *device,
				    struct tape_3590_med_sense *sense)
{
	struct tape390_crypt_info *c_info;

	c_info = &TAPE_3590_CRYPT_INFO(device);

	DBF_EVENT(6, "medium state: %x:%x\n", sense->macst, sense->masst);
	switch (sense->macst) {
	case 0x04:
	case 0x05:
	case 0x06:
		tape_med_state_set(device, MS_UNLOADED);
		TAPE_3590_CRYPT_INFO(device).medium_status = 0;
		return;
	case 0x08:
	case 0x09:
		tape_med_state_set(device, MS_LOADED);
		break;
	default:
		tape_med_state_set(device, MS_UNKNOWN);
		return;
	}
	c_info->medium_status |= TAPE390_MEDIUM_LOADED_MASK;
	if (sense->flags & MSENSE_CRYPT_MASK) {
		PRINT_INFO("Medium is encrypted (%04x)\n", sense->flags);
		c_info->medium_status |= TAPE390_MEDIUM_ENCRYPTED_MASK;
	} else	{
		DBF_EVENT(6, "Medium is not encrypted %04x\n", sense->flags);
		c_info->medium_status &= ~TAPE390_MEDIUM_ENCRYPTED_MASK;
	}
}

/*
 * 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_disc_data *disc_data;

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

	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);
		tape_3590_schedule_work(device, TO_CRYPT_OFF);
		break;
	case TO_MSEN:
		tape_3590_med_state_set(device, request->cpdata);
		break;
	case TO_CRYPT_ON:
		TAPE_3590_CRYPT_INFO(device).status
			|= TAPE390_CRYPT_ON_MASK;
		*(device->modeset_byte) |= 0x03;
		break;
	case TO_CRYPT_OFF:
		TAPE_3590_CRYPT_INFO(device).status
			&= ~TAPE390_CRYPT_ON_MASK;
		*(device->modeset_byte) &= ~0x03;
		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:
	case TO_SIZE:
	case TO_KEKL_SET:
	case TO_KEKL_QUERY:
	case TO_RDC:
		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 */
		DBF_EVENT(3, "unsol.irq! tape ready: %08x\n", device->cdev_id);
	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);
	}
	/* check medium state */
	tape_3590_schedule_work(device, TO_MSEN);
	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;
	}
}