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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /drivers/s390/cio/cio.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/s390/cio/cio.c')
-rw-r--r--drivers/s390/cio/cio.c758
1 files changed, 758 insertions, 0 deletions
diff --git a/drivers/s390/cio/cio.c b/drivers/s390/cio/cio.c
new file mode 100644
index 0000000000..6127add746
--- /dev/null
+++ b/drivers/s390/cio/cio.c
@@ -0,0 +1,758 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * S/390 common I/O routines -- low level i/o calls
+ *
+ * Copyright IBM Corp. 1999, 2008
+ * Author(s): Ingo Adlung (adlung@de.ibm.com)
+ * Cornelia Huck (cornelia.huck@de.ibm.com)
+ * Arnd Bergmann (arndb@de.ibm.com)
+ * Martin Schwidefsky (schwidefsky@de.ibm.com)
+ */
+
+#define KMSG_COMPONENT "cio"
+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
+
+#include <linux/ftrace.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/device.h>
+#include <linux/kernel_stat.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <asm/cio.h>
+#include <asm/delay.h>
+#include <asm/irq.h>
+#include <asm/irq_regs.h>
+#include <asm/setup.h>
+#include <asm/ipl.h>
+#include <asm/chpid.h>
+#include <asm/airq.h>
+#include <asm/isc.h>
+#include <linux/sched/cputime.h>
+#include <asm/fcx.h>
+#include <asm/nmi.h>
+#include <asm/crw.h>
+#include "cio.h"
+#include "css.h"
+#include "chsc.h"
+#include "ioasm.h"
+#include "io_sch.h"
+#include "blacklist.h"
+#include "cio_debug.h"
+#include "chp.h"
+#include "trace.h"
+
+debug_info_t *cio_debug_msg_id;
+debug_info_t *cio_debug_trace_id;
+debug_info_t *cio_debug_crw_id;
+
+DEFINE_PER_CPU_ALIGNED(struct irb, cio_irb);
+EXPORT_PER_CPU_SYMBOL(cio_irb);
+
+/*
+ * Function: cio_debug_init
+ * Initializes three debug logs for common I/O:
+ * - cio_msg logs generic cio messages
+ * - cio_trace logs the calling of different functions
+ * - cio_crw logs machine check related cio messages
+ */
+static int __init cio_debug_init(void)
+{
+ cio_debug_msg_id = debug_register("cio_msg", 16, 1, 11 * sizeof(long));
+ if (!cio_debug_msg_id)
+ goto out_unregister;
+ debug_register_view(cio_debug_msg_id, &debug_sprintf_view);
+ debug_set_level(cio_debug_msg_id, 2);
+ cio_debug_trace_id = debug_register("cio_trace", 16, 1, 16);
+ if (!cio_debug_trace_id)
+ goto out_unregister;
+ debug_register_view(cio_debug_trace_id, &debug_hex_ascii_view);
+ debug_set_level(cio_debug_trace_id, 2);
+ cio_debug_crw_id = debug_register("cio_crw", 8, 1, 8 * sizeof(long));
+ if (!cio_debug_crw_id)
+ goto out_unregister;
+ debug_register_view(cio_debug_crw_id, &debug_sprintf_view);
+ debug_set_level(cio_debug_crw_id, 4);
+ return 0;
+
+out_unregister:
+ debug_unregister(cio_debug_msg_id);
+ debug_unregister(cio_debug_trace_id);
+ debug_unregister(cio_debug_crw_id);
+ return -1;
+}
+
+arch_initcall (cio_debug_init);
+
+int cio_set_options(struct subchannel *sch, int flags)
+{
+ struct io_subchannel_private *priv = to_io_private(sch);
+
+ priv->options.suspend = (flags & DOIO_ALLOW_SUSPEND) != 0;
+ priv->options.prefetch = (flags & DOIO_DENY_PREFETCH) != 0;
+ priv->options.inter = (flags & DOIO_SUPPRESS_INTER) != 0;
+ return 0;
+}
+
+static int
+cio_start_handle_notoper(struct subchannel *sch, __u8 lpm)
+{
+ char dbf_text[15];
+
+ if (lpm != 0)
+ sch->lpm &= ~lpm;
+ else
+ sch->lpm = 0;
+
+ CIO_MSG_EVENT(2, "cio_start: 'not oper' status for "
+ "subchannel 0.%x.%04x!\n", sch->schid.ssid,
+ sch->schid.sch_no);
+
+ if (cio_update_schib(sch))
+ return -ENODEV;
+
+ sprintf(dbf_text, "no%s", dev_name(&sch->dev));
+ CIO_TRACE_EVENT(0, dbf_text);
+ CIO_HEX_EVENT(0, &sch->schib, sizeof (struct schib));
+
+ return (sch->lpm ? -EACCES : -ENODEV);
+}
+
+int
+cio_start_key (struct subchannel *sch, /* subchannel structure */
+ struct ccw1 * cpa, /* logical channel prog addr */
+ __u8 lpm, /* logical path mask */
+ __u8 key) /* storage key */
+{
+ struct io_subchannel_private *priv = to_io_private(sch);
+ union orb *orb = &priv->orb;
+ int ccode;
+
+ CIO_TRACE_EVENT(5, "stIO");
+ CIO_TRACE_EVENT(5, dev_name(&sch->dev));
+
+ memset(orb, 0, sizeof(union orb));
+ /* sch is always under 2G. */
+ orb->cmd.intparm = (u32)virt_to_phys(sch);
+ orb->cmd.fmt = 1;
+
+ orb->cmd.pfch = priv->options.prefetch == 0;
+ orb->cmd.spnd = priv->options.suspend;
+ orb->cmd.ssic = priv->options.suspend && priv->options.inter;
+ orb->cmd.lpm = (lpm != 0) ? lpm : sch->lpm;
+ /*
+ * for 64 bit we always support 64 bit IDAWs with 4k page size only
+ */
+ orb->cmd.c64 = 1;
+ orb->cmd.i2k = 0;
+ orb->cmd.key = key >> 4;
+ /* issue "Start Subchannel" */
+ orb->cmd.cpa = (u32)virt_to_phys(cpa);
+ ccode = ssch(sch->schid, orb);
+
+ /* process condition code */
+ CIO_HEX_EVENT(5, &ccode, sizeof(ccode));
+
+ switch (ccode) {
+ case 0:
+ /*
+ * initialize device status information
+ */
+ sch->schib.scsw.cmd.actl |= SCSW_ACTL_START_PEND;
+ return 0;
+ case 1: /* status pending */
+ case 2: /* busy */
+ return -EBUSY;
+ case 3: /* device/path not operational */
+ return cio_start_handle_notoper(sch, lpm);
+ default:
+ return ccode;
+ }
+}
+EXPORT_SYMBOL_GPL(cio_start_key);
+
+int
+cio_start (struct subchannel *sch, struct ccw1 *cpa, __u8 lpm)
+{
+ return cio_start_key(sch, cpa, lpm, PAGE_DEFAULT_KEY);
+}
+EXPORT_SYMBOL_GPL(cio_start);
+
+/*
+ * resume suspended I/O operation
+ */
+int
+cio_resume (struct subchannel *sch)
+{
+ int ccode;
+
+ CIO_TRACE_EVENT(4, "resIO");
+ CIO_TRACE_EVENT(4, dev_name(&sch->dev));
+
+ ccode = rsch (sch->schid);
+
+ CIO_HEX_EVENT(4, &ccode, sizeof(ccode));
+
+ switch (ccode) {
+ case 0:
+ sch->schib.scsw.cmd.actl |= SCSW_ACTL_RESUME_PEND;
+ return 0;
+ case 1:
+ return -EBUSY;
+ case 2:
+ return -EINVAL;
+ default:
+ /*
+ * useless to wait for request completion
+ * as device is no longer operational !
+ */
+ return -ENODEV;
+ }
+}
+EXPORT_SYMBOL_GPL(cio_resume);
+
+/*
+ * halt I/O operation
+ */
+int
+cio_halt(struct subchannel *sch)
+{
+ int ccode;
+
+ if (!sch)
+ return -ENODEV;
+
+ CIO_TRACE_EVENT(2, "haltIO");
+ CIO_TRACE_EVENT(2, dev_name(&sch->dev));
+
+ /*
+ * Issue "Halt subchannel" and process condition code
+ */
+ ccode = hsch (sch->schid);
+
+ CIO_HEX_EVENT(2, &ccode, sizeof(ccode));
+
+ switch (ccode) {
+ case 0:
+ sch->schib.scsw.cmd.actl |= SCSW_ACTL_HALT_PEND;
+ return 0;
+ case 1: /* status pending */
+ case 2: /* busy */
+ return -EBUSY;
+ default: /* device not operational */
+ return -ENODEV;
+ }
+}
+EXPORT_SYMBOL_GPL(cio_halt);
+
+/*
+ * Clear I/O operation
+ */
+int
+cio_clear(struct subchannel *sch)
+{
+ int ccode;
+
+ if (!sch)
+ return -ENODEV;
+
+ CIO_TRACE_EVENT(2, "clearIO");
+ CIO_TRACE_EVENT(2, dev_name(&sch->dev));
+
+ /*
+ * Issue "Clear subchannel" and process condition code
+ */
+ ccode = csch (sch->schid);
+
+ CIO_HEX_EVENT(2, &ccode, sizeof(ccode));
+
+ switch (ccode) {
+ case 0:
+ sch->schib.scsw.cmd.actl |= SCSW_ACTL_CLEAR_PEND;
+ return 0;
+ default: /* device not operational */
+ return -ENODEV;
+ }
+}
+EXPORT_SYMBOL_GPL(cio_clear);
+
+/*
+ * Function: cio_cancel
+ * Issues a "Cancel Subchannel" on the specified subchannel
+ * Note: We don't need any fancy intparms and flags here
+ * since xsch is executed synchronously.
+ * Only for common I/O internal use as for now.
+ */
+int
+cio_cancel (struct subchannel *sch)
+{
+ int ccode;
+
+ if (!sch)
+ return -ENODEV;
+
+ CIO_TRACE_EVENT(2, "cancelIO");
+ CIO_TRACE_EVENT(2, dev_name(&sch->dev));
+
+ ccode = xsch (sch->schid);
+
+ CIO_HEX_EVENT(2, &ccode, sizeof(ccode));
+
+ switch (ccode) {
+ case 0: /* success */
+ /* Update information in scsw. */
+ if (cio_update_schib(sch))
+ return -ENODEV;
+ return 0;
+ case 1: /* status pending */
+ return -EBUSY;
+ case 2: /* not applicable */
+ return -EINVAL;
+ default: /* not oper */
+ return -ENODEV;
+ }
+}
+EXPORT_SYMBOL_GPL(cio_cancel);
+
+/**
+ * cio_cancel_halt_clear - Cancel running I/O by performing cancel, halt
+ * and clear ordinally if subchannel is valid.
+ * @sch: subchannel on which to perform the cancel_halt_clear operation
+ * @iretry: the number of the times remained to retry the next operation
+ *
+ * This should be called repeatedly since halt/clear are asynchronous
+ * operations. We do one try with cio_cancel, three tries with cio_halt,
+ * 255 tries with cio_clear. The caller should initialize @iretry with
+ * the value 255 for its first call to this, and keep using the same
+ * @iretry in the subsequent calls until it gets a non -EBUSY return.
+ *
+ * Returns 0 if device now idle, -ENODEV for device not operational,
+ * -EBUSY if an interrupt is expected (either from halt/clear or from a
+ * status pending), and -EIO if out of retries.
+ */
+int cio_cancel_halt_clear(struct subchannel *sch, int *iretry)
+{
+ int ret;
+
+ if (cio_update_schib(sch))
+ return -ENODEV;
+ if (!sch->schib.pmcw.ena)
+ /* Not operational -> done. */
+ return 0;
+ /* Stage 1: cancel io. */
+ if (!(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_HALT_PEND) &&
+ !(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_CLEAR_PEND)) {
+ if (!scsw_is_tm(&sch->schib.scsw)) {
+ ret = cio_cancel(sch);
+ if (ret != -EINVAL)
+ return ret;
+ }
+ /*
+ * Cancel io unsuccessful or not applicable (transport mode).
+ * Continue with asynchronous instructions.
+ */
+ *iretry = 3; /* 3 halt retries. */
+ }
+ /* Stage 2: halt io. */
+ if (!(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_CLEAR_PEND)) {
+ if (*iretry) {
+ *iretry -= 1;
+ ret = cio_halt(sch);
+ if (ret != -EBUSY)
+ return (ret == 0) ? -EBUSY : ret;
+ }
+ /* Halt io unsuccessful. */
+ *iretry = 255; /* 255 clear retries. */
+ }
+ /* Stage 3: clear io. */
+ if (*iretry) {
+ *iretry -= 1;
+ ret = cio_clear(sch);
+ return (ret == 0) ? -EBUSY : ret;
+ }
+ /* Function was unsuccessful */
+ return -EIO;
+}
+EXPORT_SYMBOL_GPL(cio_cancel_halt_clear);
+
+static void cio_apply_config(struct subchannel *sch, struct schib *schib)
+{
+ schib->pmcw.intparm = sch->config.intparm;
+ schib->pmcw.mbi = sch->config.mbi;
+ schib->pmcw.isc = sch->config.isc;
+ schib->pmcw.ena = sch->config.ena;
+ schib->pmcw.mme = sch->config.mme;
+ schib->pmcw.mp = sch->config.mp;
+ schib->pmcw.csense = sch->config.csense;
+ schib->pmcw.mbfc = sch->config.mbfc;
+ if (sch->config.mbfc)
+ schib->mba = sch->config.mba;
+}
+
+static int cio_check_config(struct subchannel *sch, struct schib *schib)
+{
+ return (schib->pmcw.intparm == sch->config.intparm) &&
+ (schib->pmcw.mbi == sch->config.mbi) &&
+ (schib->pmcw.isc == sch->config.isc) &&
+ (schib->pmcw.ena == sch->config.ena) &&
+ (schib->pmcw.mme == sch->config.mme) &&
+ (schib->pmcw.mp == sch->config.mp) &&
+ (schib->pmcw.csense == sch->config.csense) &&
+ (schib->pmcw.mbfc == sch->config.mbfc) &&
+ (!sch->config.mbfc || (schib->mba == sch->config.mba));
+}
+
+/*
+ * cio_commit_config - apply configuration to the subchannel
+ */
+int cio_commit_config(struct subchannel *sch)
+{
+ int ccode, retry, ret = 0;
+ struct schib schib;
+ struct irb irb;
+
+ if (stsch(sch->schid, &schib) || !css_sch_is_valid(&schib))
+ return -ENODEV;
+
+ for (retry = 0; retry < 5; retry++) {
+ /* copy desired changes to local schib */
+ cio_apply_config(sch, &schib);
+ ccode = msch(sch->schid, &schib);
+ if (ccode < 0) /* -EIO if msch gets a program check. */
+ return ccode;
+ switch (ccode) {
+ case 0: /* successful */
+ if (stsch(sch->schid, &schib) ||
+ !css_sch_is_valid(&schib))
+ return -ENODEV;
+ if (cio_check_config(sch, &schib)) {
+ /* commit changes from local schib */
+ memcpy(&sch->schib, &schib, sizeof(schib));
+ return 0;
+ }
+ ret = -EAGAIN;
+ break;
+ case 1: /* status pending */
+ ret = -EBUSY;
+ if (tsch(sch->schid, &irb))
+ return ret;
+ break;
+ case 2: /* busy */
+ udelay(100); /* allow for recovery */
+ ret = -EBUSY;
+ break;
+ case 3: /* not operational */
+ return -ENODEV;
+ }
+ }
+ return ret;
+}
+EXPORT_SYMBOL_GPL(cio_commit_config);
+
+/**
+ * cio_update_schib - Perform stsch and update schib if subchannel is valid.
+ * @sch: subchannel on which to perform stsch
+ * Return zero on success, -ENODEV otherwise.
+ */
+int cio_update_schib(struct subchannel *sch)
+{
+ struct schib schib;
+
+ if (stsch(sch->schid, &schib) || !css_sch_is_valid(&schib))
+ return -ENODEV;
+
+ memcpy(&sch->schib, &schib, sizeof(schib));
+ return 0;
+}
+EXPORT_SYMBOL_GPL(cio_update_schib);
+
+/**
+ * cio_enable_subchannel - enable a subchannel.
+ * @sch: subchannel to be enabled
+ * @intparm: interruption parameter to set
+ */
+int cio_enable_subchannel(struct subchannel *sch, u32 intparm)
+{
+ int ret;
+
+ CIO_TRACE_EVENT(2, "ensch");
+ CIO_TRACE_EVENT(2, dev_name(&sch->dev));
+
+ if (sch_is_pseudo_sch(sch))
+ return -EINVAL;
+ if (cio_update_schib(sch))
+ return -ENODEV;
+
+ sch->config.ena = 1;
+ sch->config.isc = sch->isc;
+ sch->config.intparm = intparm;
+
+ ret = cio_commit_config(sch);
+ if (ret == -EIO) {
+ /*
+ * Got a program check in msch. Try without
+ * the concurrent sense bit the next time.
+ */
+ sch->config.csense = 0;
+ ret = cio_commit_config(sch);
+ }
+ CIO_HEX_EVENT(2, &ret, sizeof(ret));
+ return ret;
+}
+EXPORT_SYMBOL_GPL(cio_enable_subchannel);
+
+/**
+ * cio_disable_subchannel - disable a subchannel.
+ * @sch: subchannel to disable
+ */
+int cio_disable_subchannel(struct subchannel *sch)
+{
+ int ret;
+
+ CIO_TRACE_EVENT(2, "dissch");
+ CIO_TRACE_EVENT(2, dev_name(&sch->dev));
+
+ if (sch_is_pseudo_sch(sch))
+ return 0;
+ if (cio_update_schib(sch))
+ return -ENODEV;
+
+ sch->config.ena = 0;
+ ret = cio_commit_config(sch);
+
+ CIO_HEX_EVENT(2, &ret, sizeof(ret));
+ return ret;
+}
+EXPORT_SYMBOL_GPL(cio_disable_subchannel);
+
+/*
+ * do_cio_interrupt() handles all normal I/O device IRQ's
+ */
+static irqreturn_t do_cio_interrupt(int irq, void *dummy)
+{
+ struct tpi_info *tpi_info;
+ struct subchannel *sch;
+ struct irb *irb;
+
+ set_cpu_flag(CIF_NOHZ_DELAY);
+ tpi_info = &get_irq_regs()->tpi_info;
+ trace_s390_cio_interrupt(tpi_info);
+ irb = this_cpu_ptr(&cio_irb);
+ if (!tpi_info->intparm) {
+ /* Clear pending interrupt condition. */
+ inc_irq_stat(IRQIO_CIO);
+ tsch(tpi_info->schid, irb);
+ return IRQ_HANDLED;
+ }
+ sch = phys_to_virt(tpi_info->intparm);
+ spin_lock(sch->lock);
+ /* Store interrupt response block to lowcore. */
+ if (tsch(tpi_info->schid, irb) == 0) {
+ /* Keep subchannel information word up to date. */
+ memcpy (&sch->schib.scsw, &irb->scsw, sizeof (irb->scsw));
+ /* Call interrupt handler if there is one. */
+ if (sch->driver && sch->driver->irq)
+ sch->driver->irq(sch);
+ else
+ inc_irq_stat(IRQIO_CIO);
+ } else
+ inc_irq_stat(IRQIO_CIO);
+ spin_unlock(sch->lock);
+
+ return IRQ_HANDLED;
+}
+
+void __init init_cio_interrupts(void)
+{
+ irq_set_chip_and_handler(IO_INTERRUPT,
+ &dummy_irq_chip, handle_percpu_irq);
+ if (request_irq(IO_INTERRUPT, do_cio_interrupt, 0, "I/O", NULL))
+ panic("Failed to register I/O interrupt\n");
+}
+
+#ifdef CONFIG_CCW_CONSOLE
+static struct subchannel *console_sch;
+static struct lock_class_key console_sch_key;
+
+/*
+ * Use cio_tsch to update the subchannel status and call the interrupt handler
+ * if status had been pending. Called with the subchannel's lock held.
+ */
+void cio_tsch(struct subchannel *sch)
+{
+ struct irb *irb;
+ int irq_context;
+
+ irb = this_cpu_ptr(&cio_irb);
+ /* Store interrupt response block to lowcore. */
+ if (tsch(sch->schid, irb) != 0)
+ /* Not status pending or not operational. */
+ return;
+ memcpy(&sch->schib.scsw, &irb->scsw, sizeof(union scsw));
+ /* Call interrupt handler with updated status. */
+ irq_context = in_interrupt();
+ if (!irq_context) {
+ local_bh_disable();
+ irq_enter();
+ }
+ kstat_incr_irq_this_cpu(IO_INTERRUPT);
+ if (sch->driver && sch->driver->irq)
+ sch->driver->irq(sch);
+ else
+ inc_irq_stat(IRQIO_CIO);
+ if (!irq_context) {
+ irq_exit();
+ _local_bh_enable();
+ }
+}
+
+static int cio_test_for_console(struct subchannel_id schid, void *data)
+{
+ struct schib schib;
+
+ if (stsch(schid, &schib) != 0)
+ return -ENXIO;
+ if ((schib.pmcw.st == SUBCHANNEL_TYPE_IO) && schib.pmcw.dnv &&
+ (schib.pmcw.dev == console_devno)) {
+ console_irq = schid.sch_no;
+ return 1; /* found */
+ }
+ return 0;
+}
+
+static int cio_get_console_sch_no(void)
+{
+ struct subchannel_id schid;
+ struct schib schib;
+
+ init_subchannel_id(&schid);
+ if (console_irq != -1) {
+ /* VM provided us with the irq number of the console. */
+ schid.sch_no = console_irq;
+ if (stsch(schid, &schib) != 0 ||
+ (schib.pmcw.st != SUBCHANNEL_TYPE_IO) || !schib.pmcw.dnv)
+ return -1;
+ console_devno = schib.pmcw.dev;
+ } else if (console_devno != -1) {
+ /* At least the console device number is known. */
+ for_each_subchannel(cio_test_for_console, NULL);
+ }
+ return console_irq;
+}
+
+struct subchannel *cio_probe_console(void)
+{
+ struct subchannel_id schid;
+ struct subchannel *sch;
+ struct schib schib;
+ int sch_no, ret;
+
+ sch_no = cio_get_console_sch_no();
+ if (sch_no == -1) {
+ pr_warn("No CCW console was found\n");
+ return ERR_PTR(-ENODEV);
+ }
+ init_subchannel_id(&schid);
+ schid.sch_no = sch_no;
+ ret = stsch(schid, &schib);
+ if (ret)
+ return ERR_PTR(-ENODEV);
+
+ sch = css_alloc_subchannel(schid, &schib);
+ if (IS_ERR(sch))
+ return sch;
+
+ lockdep_set_class(sch->lock, &console_sch_key);
+ isc_register(CONSOLE_ISC);
+ sch->config.isc = CONSOLE_ISC;
+ sch->config.intparm = (u32)virt_to_phys(sch);
+ ret = cio_commit_config(sch);
+ if (ret) {
+ isc_unregister(CONSOLE_ISC);
+ put_device(&sch->dev);
+ return ERR_PTR(ret);
+ }
+ console_sch = sch;
+ return sch;
+}
+
+int cio_is_console(struct subchannel_id schid)
+{
+ if (!console_sch)
+ return 0;
+ return schid_equal(&schid, &console_sch->schid);
+}
+
+void cio_register_early_subchannels(void)
+{
+ int ret;
+
+ if (!console_sch)
+ return;
+
+ ret = css_register_subchannel(console_sch);
+ if (ret)
+ put_device(&console_sch->dev);
+}
+#endif /* CONFIG_CCW_CONSOLE */
+
+/**
+ * cio_tm_start_key - perform start function
+ * @sch: subchannel on which to perform the start function
+ * @tcw: transport-command word to be started
+ * @lpm: mask of paths to use
+ * @key: storage key to use for storage access
+ *
+ * Start the tcw on the given subchannel. Return zero on success, non-zero
+ * otherwise.
+ */
+int cio_tm_start_key(struct subchannel *sch, struct tcw *tcw, u8 lpm, u8 key)
+{
+ int cc;
+ union orb *orb = &to_io_private(sch)->orb;
+
+ memset(orb, 0, sizeof(union orb));
+ orb->tm.intparm = (u32)virt_to_phys(sch);
+ orb->tm.key = key >> 4;
+ orb->tm.b = 1;
+ orb->tm.lpm = lpm ? lpm : sch->lpm;
+ orb->tm.tcw = (u32)virt_to_phys(tcw);
+ cc = ssch(sch->schid, orb);
+ switch (cc) {
+ case 0:
+ return 0;
+ case 1:
+ case 2:
+ return -EBUSY;
+ default:
+ return cio_start_handle_notoper(sch, lpm);
+ }
+}
+EXPORT_SYMBOL_GPL(cio_tm_start_key);
+
+/**
+ * cio_tm_intrg - perform interrogate function
+ * @sch: subchannel on which to perform the interrogate function
+ *
+ * If the specified subchannel is running in transport-mode, perform the
+ * interrogate function. Return zero on success, non-zero otherwie.
+ */
+int cio_tm_intrg(struct subchannel *sch)
+{
+ int cc;
+
+ if (!to_io_private(sch)->orb.tm.b)
+ return -EINVAL;
+ cc = xsch(sch->schid);
+ switch (cc) {
+ case 0:
+ case 2:
+ return 0;
+ case 1:
+ return -EBUSY;
+ default:
+ return -ENODEV;
+ }
+}
+EXPORT_SYMBOL_GPL(cio_tm_intrg);