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path: root/drivers/s390/cio/device_ops.c
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Diffstat (limited to 'drivers/s390/cio/device_ops.c')
-rw-r--r--drivers/s390/cio/device_ops.c799
1 files changed, 799 insertions, 0 deletions
diff --git a/drivers/s390/cio/device_ops.c b/drivers/s390/cio/device_ops.c
new file mode 100644
index 000000000..f3c417943
--- /dev/null
+++ b/drivers/s390/cio/device_ops.c
@@ -0,0 +1,799 @@
+/*
+ * Copyright IBM Corp. 2002, 2009
+ *
+ * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
+ * Cornelia Huck (cornelia.huck@de.ibm.com)
+ */
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/slab.h>
+#include <linux/list.h>
+#include <linux/device.h>
+#include <linux/delay.h>
+#include <linux/completion.h>
+
+#include <asm/ccwdev.h>
+#include <asm/idals.h>
+#include <asm/chpid.h>
+#include <asm/fcx.h>
+
+#include "cio.h"
+#include "cio_debug.h"
+#include "css.h"
+#include "chsc.h"
+#include "device.h"
+#include "chp.h"
+
+/**
+ * ccw_device_set_options_mask() - set some options and unset the rest
+ * @cdev: device for which the options are to be set
+ * @flags: options to be set
+ *
+ * All flags specified in @flags are set, all flags not specified in @flags
+ * are cleared.
+ * Returns:
+ * %0 on success, -%EINVAL on an invalid flag combination.
+ */
+int ccw_device_set_options_mask(struct ccw_device *cdev, unsigned long flags)
+{
+ /*
+ * The flag usage is mutal exclusive ...
+ */
+ if ((flags & CCWDEV_EARLY_NOTIFICATION) &&
+ (flags & CCWDEV_REPORT_ALL))
+ return -EINVAL;
+ cdev->private->options.fast = (flags & CCWDEV_EARLY_NOTIFICATION) != 0;
+ cdev->private->options.repall = (flags & CCWDEV_REPORT_ALL) != 0;
+ cdev->private->options.pgroup = (flags & CCWDEV_DO_PATHGROUP) != 0;
+ cdev->private->options.force = (flags & CCWDEV_ALLOW_FORCE) != 0;
+ cdev->private->options.mpath = (flags & CCWDEV_DO_MULTIPATH) != 0;
+ return 0;
+}
+
+/**
+ * ccw_device_set_options() - set some options
+ * @cdev: device for which the options are to be set
+ * @flags: options to be set
+ *
+ * All flags specified in @flags are set, the remainder is left untouched.
+ * Returns:
+ * %0 on success, -%EINVAL if an invalid flag combination would ensue.
+ */
+int ccw_device_set_options(struct ccw_device *cdev, unsigned long flags)
+{
+ /*
+ * The flag usage is mutal exclusive ...
+ */
+ if (((flags & CCWDEV_EARLY_NOTIFICATION) &&
+ (flags & CCWDEV_REPORT_ALL)) ||
+ ((flags & CCWDEV_EARLY_NOTIFICATION) &&
+ cdev->private->options.repall) ||
+ ((flags & CCWDEV_REPORT_ALL) &&
+ cdev->private->options.fast))
+ return -EINVAL;
+ cdev->private->options.fast |= (flags & CCWDEV_EARLY_NOTIFICATION) != 0;
+ cdev->private->options.repall |= (flags & CCWDEV_REPORT_ALL) != 0;
+ cdev->private->options.pgroup |= (flags & CCWDEV_DO_PATHGROUP) != 0;
+ cdev->private->options.force |= (flags & CCWDEV_ALLOW_FORCE) != 0;
+ cdev->private->options.mpath |= (flags & CCWDEV_DO_MULTIPATH) != 0;
+ return 0;
+}
+
+/**
+ * ccw_device_clear_options() - clear some options
+ * @cdev: device for which the options are to be cleared
+ * @flags: options to be cleared
+ *
+ * All flags specified in @flags are cleared, the remainder is left untouched.
+ */
+void ccw_device_clear_options(struct ccw_device *cdev, unsigned long flags)
+{
+ cdev->private->options.fast &= (flags & CCWDEV_EARLY_NOTIFICATION) == 0;
+ cdev->private->options.repall &= (flags & CCWDEV_REPORT_ALL) == 0;
+ cdev->private->options.pgroup &= (flags & CCWDEV_DO_PATHGROUP) == 0;
+ cdev->private->options.force &= (flags & CCWDEV_ALLOW_FORCE) == 0;
+ cdev->private->options.mpath &= (flags & CCWDEV_DO_MULTIPATH) == 0;
+}
+
+/**
+ * ccw_device_is_pathgroup - determine if paths to this device are grouped
+ * @cdev: ccw device
+ *
+ * Return non-zero if there is a path group, zero otherwise.
+ */
+int ccw_device_is_pathgroup(struct ccw_device *cdev)
+{
+ return cdev->private->flags.pgroup;
+}
+EXPORT_SYMBOL(ccw_device_is_pathgroup);
+
+/**
+ * ccw_device_is_multipath - determine if device is operating in multipath mode
+ * @cdev: ccw device
+ *
+ * Return non-zero if device is operating in multipath mode, zero otherwise.
+ */
+int ccw_device_is_multipath(struct ccw_device *cdev)
+{
+ return cdev->private->flags.mpath;
+}
+EXPORT_SYMBOL(ccw_device_is_multipath);
+
+/**
+ * ccw_device_clear() - terminate I/O request processing
+ * @cdev: target ccw device
+ * @intparm: interruption parameter; value is only used if no I/O is
+ * outstanding, otherwise the intparm associated with the I/O request
+ * is returned
+ *
+ * ccw_device_clear() calls csch on @cdev's subchannel.
+ * Returns:
+ * %0 on success,
+ * -%ENODEV on device not operational,
+ * -%EINVAL on invalid device state.
+ * Context:
+ * Interrupts disabled, ccw device lock held
+ */
+int ccw_device_clear(struct ccw_device *cdev, unsigned long intparm)
+{
+ struct subchannel *sch;
+ int ret;
+
+ if (!cdev || !cdev->dev.parent)
+ return -ENODEV;
+ sch = to_subchannel(cdev->dev.parent);
+ if (!sch->schib.pmcw.ena)
+ return -EINVAL;
+ if (cdev->private->state == DEV_STATE_NOT_OPER)
+ return -ENODEV;
+ if (cdev->private->state != DEV_STATE_ONLINE &&
+ cdev->private->state != DEV_STATE_W4SENSE)
+ return -EINVAL;
+
+ ret = cio_clear(sch);
+ if (ret == 0)
+ cdev->private->intparm = intparm;
+ return ret;
+}
+
+/**
+ * ccw_device_start_key() - start a s390 channel program with key
+ * @cdev: target ccw device
+ * @cpa: logical start address of channel program
+ * @intparm: user specific interruption parameter; will be presented back to
+ * @cdev's interrupt handler. Allows a device driver to associate
+ * the interrupt with a particular I/O request.
+ * @lpm: defines the channel path to be used for a specific I/O request. A
+ * value of 0 will make cio use the opm.
+ * @key: storage key to be used for the I/O
+ * @flags: additional flags; defines the action to be performed for I/O
+ * processing.
+ *
+ * Start a S/390 channel program. When the interrupt arrives, the
+ * IRQ handler is called, either immediately, delayed (dev-end missing,
+ * or sense required) or never (no IRQ handler registered).
+ * Returns:
+ * %0, if the operation was successful;
+ * -%EBUSY, if the device is busy, or status pending;
+ * -%EACCES, if no path specified in @lpm is operational;
+ * -%ENODEV, if the device is not operational.
+ * Context:
+ * Interrupts disabled, ccw device lock held
+ */
+int ccw_device_start_key(struct ccw_device *cdev, struct ccw1 *cpa,
+ unsigned long intparm, __u8 lpm, __u8 key,
+ unsigned long flags)
+{
+ struct subchannel *sch;
+ int ret;
+
+ if (!cdev || !cdev->dev.parent)
+ return -ENODEV;
+ sch = to_subchannel(cdev->dev.parent);
+ if (!sch->schib.pmcw.ena)
+ return -EINVAL;
+ if (cdev->private->state == DEV_STATE_NOT_OPER)
+ return -ENODEV;
+ if (cdev->private->state == DEV_STATE_VERIFY) {
+ /* Remember to fake irb when finished. */
+ if (!cdev->private->flags.fake_irb) {
+ cdev->private->flags.fake_irb = FAKE_CMD_IRB;
+ cdev->private->intparm = intparm;
+ return 0;
+ } else
+ /* There's already a fake I/O around. */
+ return -EBUSY;
+ }
+ if (cdev->private->state != DEV_STATE_ONLINE ||
+ ((sch->schib.scsw.cmd.stctl & SCSW_STCTL_PRIM_STATUS) &&
+ !(sch->schib.scsw.cmd.stctl & SCSW_STCTL_SEC_STATUS)) ||
+ cdev->private->flags.doverify)
+ return -EBUSY;
+ ret = cio_set_options (sch, flags);
+ if (ret)
+ return ret;
+ /* Adjust requested path mask to exclude unusable paths. */
+ if (lpm) {
+ lpm &= sch->lpm;
+ if (lpm == 0)
+ return -EACCES;
+ }
+ ret = cio_start_key (sch, cpa, lpm, key);
+ switch (ret) {
+ case 0:
+ cdev->private->intparm = intparm;
+ break;
+ case -EACCES:
+ case -ENODEV:
+ dev_fsm_event(cdev, DEV_EVENT_VERIFY);
+ break;
+ }
+ return ret;
+}
+
+/**
+ * ccw_device_start_timeout_key() - start a s390 channel program with timeout and key
+ * @cdev: target ccw device
+ * @cpa: logical start address of channel program
+ * @intparm: user specific interruption parameter; will be presented back to
+ * @cdev's interrupt handler. Allows a device driver to associate
+ * the interrupt with a particular I/O request.
+ * @lpm: defines the channel path to be used for a specific I/O request. A
+ * value of 0 will make cio use the opm.
+ * @key: storage key to be used for the I/O
+ * @flags: additional flags; defines the action to be performed for I/O
+ * processing.
+ * @expires: timeout value in jiffies
+ *
+ * Start a S/390 channel program. When the interrupt arrives, the
+ * IRQ handler is called, either immediately, delayed (dev-end missing,
+ * or sense required) or never (no IRQ handler registered).
+ * This function notifies the device driver if the channel program has not
+ * completed during the time specified by @expires. If a timeout occurs, the
+ * channel program is terminated via xsch, hsch or csch, and the device's
+ * interrupt handler will be called with an irb containing ERR_PTR(-%ETIMEDOUT).
+ * Returns:
+ * %0, if the operation was successful;
+ * -%EBUSY, if the device is busy, or status pending;
+ * -%EACCES, if no path specified in @lpm is operational;
+ * -%ENODEV, if the device is not operational.
+ * Context:
+ * Interrupts disabled, ccw device lock held
+ */
+int ccw_device_start_timeout_key(struct ccw_device *cdev, struct ccw1 *cpa,
+ unsigned long intparm, __u8 lpm, __u8 key,
+ unsigned long flags, int expires)
+{
+ int ret;
+
+ if (!cdev)
+ return -ENODEV;
+ ccw_device_set_timeout(cdev, expires);
+ ret = ccw_device_start_key(cdev, cpa, intparm, lpm, key, flags);
+ if (ret != 0)
+ ccw_device_set_timeout(cdev, 0);
+ return ret;
+}
+
+/**
+ * ccw_device_start() - start a s390 channel program
+ * @cdev: target ccw device
+ * @cpa: logical start address of channel program
+ * @intparm: user specific interruption parameter; will be presented back to
+ * @cdev's interrupt handler. Allows a device driver to associate
+ * the interrupt with a particular I/O request.
+ * @lpm: defines the channel path to be used for a specific I/O request. A
+ * value of 0 will make cio use the opm.
+ * @flags: additional flags; defines the action to be performed for I/O
+ * processing.
+ *
+ * Start a S/390 channel program. When the interrupt arrives, the
+ * IRQ handler is called, either immediately, delayed (dev-end missing,
+ * or sense required) or never (no IRQ handler registered).
+ * Returns:
+ * %0, if the operation was successful;
+ * -%EBUSY, if the device is busy, or status pending;
+ * -%EACCES, if no path specified in @lpm is operational;
+ * -%ENODEV, if the device is not operational.
+ * Context:
+ * Interrupts disabled, ccw device lock held
+ */
+int ccw_device_start(struct ccw_device *cdev, struct ccw1 *cpa,
+ unsigned long intparm, __u8 lpm, unsigned long flags)
+{
+ return ccw_device_start_key(cdev, cpa, intparm, lpm,
+ PAGE_DEFAULT_KEY, flags);
+}
+
+/**
+ * ccw_device_start_timeout() - start a s390 channel program with timeout
+ * @cdev: target ccw device
+ * @cpa: logical start address of channel program
+ * @intparm: user specific interruption parameter; will be presented back to
+ * @cdev's interrupt handler. Allows a device driver to associate
+ * the interrupt with a particular I/O request.
+ * @lpm: defines the channel path to be used for a specific I/O request. A
+ * value of 0 will make cio use the opm.
+ * @flags: additional flags; defines the action to be performed for I/O
+ * processing.
+ * @expires: timeout value in jiffies
+ *
+ * Start a S/390 channel program. When the interrupt arrives, the
+ * IRQ handler is called, either immediately, delayed (dev-end missing,
+ * or sense required) or never (no IRQ handler registered).
+ * This function notifies the device driver if the channel program has not
+ * completed during the time specified by @expires. If a timeout occurs, the
+ * channel program is terminated via xsch, hsch or csch, and the device's
+ * interrupt handler will be called with an irb containing ERR_PTR(-%ETIMEDOUT).
+ * Returns:
+ * %0, if the operation was successful;
+ * -%EBUSY, if the device is busy, or status pending;
+ * -%EACCES, if no path specified in @lpm is operational;
+ * -%ENODEV, if the device is not operational.
+ * Context:
+ * Interrupts disabled, ccw device lock held
+ */
+int ccw_device_start_timeout(struct ccw_device *cdev, struct ccw1 *cpa,
+ unsigned long intparm, __u8 lpm,
+ unsigned long flags, int expires)
+{
+ return ccw_device_start_timeout_key(cdev, cpa, intparm, lpm,
+ PAGE_DEFAULT_KEY, flags,
+ expires);
+}
+
+
+/**
+ * ccw_device_halt() - halt I/O request processing
+ * @cdev: target ccw device
+ * @intparm: interruption parameter; value is only used if no I/O is
+ * outstanding, otherwise the intparm associated with the I/O request
+ * is returned
+ *
+ * ccw_device_halt() calls hsch on @cdev's subchannel.
+ * Returns:
+ * %0 on success,
+ * -%ENODEV on device not operational,
+ * -%EINVAL on invalid device state,
+ * -%EBUSY on device busy or interrupt pending.
+ * Context:
+ * Interrupts disabled, ccw device lock held
+ */
+int ccw_device_halt(struct ccw_device *cdev, unsigned long intparm)
+{
+ struct subchannel *sch;
+ int ret;
+
+ if (!cdev || !cdev->dev.parent)
+ return -ENODEV;
+ sch = to_subchannel(cdev->dev.parent);
+ if (!sch->schib.pmcw.ena)
+ return -EINVAL;
+ if (cdev->private->state == DEV_STATE_NOT_OPER)
+ return -ENODEV;
+ if (cdev->private->state != DEV_STATE_ONLINE &&
+ cdev->private->state != DEV_STATE_W4SENSE)
+ return -EINVAL;
+
+ ret = cio_halt(sch);
+ if (ret == 0)
+ cdev->private->intparm = intparm;
+ return ret;
+}
+
+/**
+ * ccw_device_resume() - resume channel program execution
+ * @cdev: target ccw device
+ *
+ * ccw_device_resume() calls rsch on @cdev's subchannel.
+ * Returns:
+ * %0 on success,
+ * -%ENODEV on device not operational,
+ * -%EINVAL on invalid device state,
+ * -%EBUSY on device busy or interrupt pending.
+ * Context:
+ * Interrupts disabled, ccw device lock held
+ */
+int ccw_device_resume(struct ccw_device *cdev)
+{
+ struct subchannel *sch;
+
+ if (!cdev || !cdev->dev.parent)
+ return -ENODEV;
+ sch = to_subchannel(cdev->dev.parent);
+ if (!sch->schib.pmcw.ena)
+ return -EINVAL;
+ if (cdev->private->state == DEV_STATE_NOT_OPER)
+ return -ENODEV;
+ if (cdev->private->state != DEV_STATE_ONLINE ||
+ !(sch->schib.scsw.cmd.actl & SCSW_ACTL_SUSPENDED))
+ return -EINVAL;
+ return cio_resume(sch);
+}
+
+/*
+ * Pass interrupt to device driver.
+ */
+int
+ccw_device_call_handler(struct ccw_device *cdev)
+{
+ unsigned int stctl;
+ int ending_status;
+
+ /*
+ * we allow for the device action handler if .
+ * - we received ending status
+ * - the action handler requested to see all interrupts
+ * - we received an intermediate status
+ * - fast notification was requested (primary status)
+ * - unsolicited interrupts
+ */
+ stctl = scsw_stctl(&cdev->private->irb.scsw);
+ ending_status = (stctl & SCSW_STCTL_SEC_STATUS) ||
+ (stctl == (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND)) ||
+ (stctl == SCSW_STCTL_STATUS_PEND);
+ if (!ending_status &&
+ !cdev->private->options.repall &&
+ !(stctl & SCSW_STCTL_INTER_STATUS) &&
+ !(cdev->private->options.fast &&
+ (stctl & SCSW_STCTL_PRIM_STATUS)))
+ return 0;
+
+ /* Clear pending timers for device driver initiated I/O. */
+ if (ending_status)
+ ccw_device_set_timeout(cdev, 0);
+ /*
+ * Now we are ready to call the device driver interrupt handler.
+ */
+ if (cdev->handler)
+ cdev->handler(cdev, cdev->private->intparm,
+ &cdev->private->irb);
+
+ /*
+ * Clear the old and now useless interrupt response block.
+ */
+ memset(&cdev->private->irb, 0, sizeof(struct irb));
+
+ return 1;
+}
+
+/**
+ * ccw_device_get_ciw() - Search for CIW command in extended sense data.
+ * @cdev: ccw device to inspect
+ * @ct: command type to look for
+ *
+ * During SenseID, command information words (CIWs) describing special
+ * commands available to the device may have been stored in the extended
+ * sense data. This function searches for CIWs of a specified command
+ * type in the extended sense data.
+ * Returns:
+ * %NULL if no extended sense data has been stored or if no CIW of the
+ * specified command type could be found,
+ * else a pointer to the CIW of the specified command type.
+ */
+struct ciw *ccw_device_get_ciw(struct ccw_device *cdev, __u32 ct)
+{
+ int ciw_cnt;
+
+ if (cdev->private->flags.esid == 0)
+ return NULL;
+ for (ciw_cnt = 0; ciw_cnt < MAX_CIWS; ciw_cnt++)
+ if (cdev->private->senseid.ciw[ciw_cnt].ct == ct)
+ return cdev->private->senseid.ciw + ciw_cnt;
+ return NULL;
+}
+
+/**
+ * ccw_device_get_path_mask() - get currently available paths
+ * @cdev: ccw device to be queried
+ * Returns:
+ * %0 if no subchannel for the device is available,
+ * else the mask of currently available paths for the ccw device's subchannel.
+ */
+__u8 ccw_device_get_path_mask(struct ccw_device *cdev)
+{
+ struct subchannel *sch;
+
+ if (!cdev->dev.parent)
+ return 0;
+
+ sch = to_subchannel(cdev->dev.parent);
+ return sch->lpm;
+}
+
+struct stlck_data {
+ struct completion done;
+ int rc;
+};
+
+void ccw_device_stlck_done(struct ccw_device *cdev, void *data, int rc)
+{
+ struct stlck_data *sdata = data;
+
+ sdata->rc = rc;
+ complete(&sdata->done);
+}
+
+/*
+ * Perform unconditional reserve + release.
+ */
+int ccw_device_stlck(struct ccw_device *cdev)
+{
+ struct subchannel *sch = to_subchannel(cdev->dev.parent);
+ struct stlck_data data;
+ u8 *buffer;
+ int rc;
+
+ /* Check if steal lock operation is valid for this device. */
+ if (cdev->drv) {
+ if (!cdev->private->options.force)
+ return -EINVAL;
+ }
+ buffer = kzalloc(64, GFP_DMA | GFP_KERNEL);
+ if (!buffer)
+ return -ENOMEM;
+ init_completion(&data.done);
+ data.rc = -EIO;
+ spin_lock_irq(sch->lock);
+ rc = cio_enable_subchannel(sch, (u32) (addr_t) sch);
+ if (rc)
+ goto out_unlock;
+ /* Perform operation. */
+ cdev->private->state = DEV_STATE_STEAL_LOCK,
+ ccw_device_stlck_start(cdev, &data, &buffer[0], &buffer[32]);
+ spin_unlock_irq(sch->lock);
+ /* Wait for operation to finish. */
+ if (wait_for_completion_interruptible(&data.done)) {
+ /* Got a signal. */
+ spin_lock_irq(sch->lock);
+ ccw_request_cancel(cdev);
+ spin_unlock_irq(sch->lock);
+ wait_for_completion(&data.done);
+ }
+ rc = data.rc;
+ /* Check results. */
+ spin_lock_irq(sch->lock);
+ cio_disable_subchannel(sch);
+ cdev->private->state = DEV_STATE_BOXED;
+out_unlock:
+ spin_unlock_irq(sch->lock);
+ kfree(buffer);
+
+ return rc;
+}
+
+/**
+ * chp_get_chp_desc - return newly allocated channel-path descriptor
+ * @cdev: device to obtain the descriptor for
+ * @chp_idx: index of the channel path
+ *
+ * On success return a newly allocated copy of the channel-path description
+ * data associated with the given channel path. Return %NULL on error.
+ */
+struct channel_path_desc *ccw_device_get_chp_desc(struct ccw_device *cdev,
+ int chp_idx)
+{
+ struct subchannel *sch;
+ struct chp_id chpid;
+
+ sch = to_subchannel(cdev->dev.parent);
+ chp_id_init(&chpid);
+ chpid.id = sch->schib.pmcw.chpid[chp_idx];
+ return chp_get_chp_desc(chpid);
+}
+
+/**
+ * ccw_device_get_id - obtain a ccw device id
+ * @cdev: device to obtain the id for
+ * @dev_id: where to fill in the values
+ */
+void ccw_device_get_id(struct ccw_device *cdev, struct ccw_dev_id *dev_id)
+{
+ *dev_id = cdev->private->dev_id;
+}
+EXPORT_SYMBOL(ccw_device_get_id);
+
+/**
+ * ccw_device_tm_start_key - perform start function
+ * @cdev: ccw device on which to perform the start function
+ * @tcw: transport-command word to be started
+ * @intparm: user defined parameter to be passed to the interrupt handler
+ * @lpm: mask of paths to use
+ * @key: storage key to use for storage access
+ *
+ * Start the tcw on the given ccw device. Return zero on success, non-zero
+ * otherwise.
+ */
+int ccw_device_tm_start_key(struct ccw_device *cdev, struct tcw *tcw,
+ unsigned long intparm, u8 lpm, u8 key)
+{
+ struct subchannel *sch;
+ int rc;
+
+ sch = to_subchannel(cdev->dev.parent);
+ if (!sch->schib.pmcw.ena)
+ return -EINVAL;
+ if (cdev->private->state == DEV_STATE_VERIFY) {
+ /* Remember to fake irb when finished. */
+ if (!cdev->private->flags.fake_irb) {
+ cdev->private->flags.fake_irb = FAKE_TM_IRB;
+ cdev->private->intparm = intparm;
+ return 0;
+ } else
+ /* There's already a fake I/O around. */
+ return -EBUSY;
+ }
+ if (cdev->private->state != DEV_STATE_ONLINE)
+ return -EIO;
+ /* Adjust requested path mask to exclude unusable paths. */
+ if (lpm) {
+ lpm &= sch->lpm;
+ if (lpm == 0)
+ return -EACCES;
+ }
+ rc = cio_tm_start_key(sch, tcw, lpm, key);
+ if (rc == 0)
+ cdev->private->intparm = intparm;
+ return rc;
+}
+EXPORT_SYMBOL(ccw_device_tm_start_key);
+
+/**
+ * ccw_device_tm_start_timeout_key - perform start function
+ * @cdev: ccw device on which to perform the start function
+ * @tcw: transport-command word to be started
+ * @intparm: user defined parameter to be passed to the interrupt handler
+ * @lpm: mask of paths to use
+ * @key: storage key to use for storage access
+ * @expires: time span in jiffies after which to abort request
+ *
+ * Start the tcw on the given ccw device. Return zero on success, non-zero
+ * otherwise.
+ */
+int ccw_device_tm_start_timeout_key(struct ccw_device *cdev, struct tcw *tcw,
+ unsigned long intparm, u8 lpm, u8 key,
+ int expires)
+{
+ int ret;
+
+ ccw_device_set_timeout(cdev, expires);
+ ret = ccw_device_tm_start_key(cdev, tcw, intparm, lpm, key);
+ if (ret != 0)
+ ccw_device_set_timeout(cdev, 0);
+ return ret;
+}
+EXPORT_SYMBOL(ccw_device_tm_start_timeout_key);
+
+/**
+ * ccw_device_tm_start - perform start function
+ * @cdev: ccw device on which to perform the start function
+ * @tcw: transport-command word to be started
+ * @intparm: user defined parameter to be passed to the interrupt handler
+ * @lpm: mask of paths to use
+ *
+ * Start the tcw on the given ccw device. Return zero on success, non-zero
+ * otherwise.
+ */
+int ccw_device_tm_start(struct ccw_device *cdev, struct tcw *tcw,
+ unsigned long intparm, u8 lpm)
+{
+ return ccw_device_tm_start_key(cdev, tcw, intparm, lpm,
+ PAGE_DEFAULT_KEY);
+}
+EXPORT_SYMBOL(ccw_device_tm_start);
+
+/**
+ * ccw_device_tm_start_timeout - perform start function
+ * @cdev: ccw device on which to perform the start function
+ * @tcw: transport-command word to be started
+ * @intparm: user defined parameter to be passed to the interrupt handler
+ * @lpm: mask of paths to use
+ * @expires: time span in jiffies after which to abort request
+ *
+ * Start the tcw on the given ccw device. Return zero on success, non-zero
+ * otherwise.
+ */
+int ccw_device_tm_start_timeout(struct ccw_device *cdev, struct tcw *tcw,
+ unsigned long intparm, u8 lpm, int expires)
+{
+ return ccw_device_tm_start_timeout_key(cdev, tcw, intparm, lpm,
+ PAGE_DEFAULT_KEY, expires);
+}
+EXPORT_SYMBOL(ccw_device_tm_start_timeout);
+
+/**
+ * ccw_device_get_mdc - accumulate max data count
+ * @cdev: ccw device for which the max data count is accumulated
+ * @mask: mask of paths to use
+ *
+ * Return the number of 64K-bytes blocks all paths at least support
+ * for a transport command. Return values <= 0 indicate failures.
+ */
+int ccw_device_get_mdc(struct ccw_device *cdev, u8 mask)
+{
+ struct subchannel *sch = to_subchannel(cdev->dev.parent);
+ struct channel_path *chp;
+ struct chp_id chpid;
+ int mdc = 0, i;
+
+ /* Adjust requested path mask to excluded varied off paths. */
+ if (mask)
+ mask &= sch->lpm;
+ else
+ mask = sch->lpm;
+
+ chp_id_init(&chpid);
+ for (i = 0; i < 8; i++) {
+ if (!(mask & (0x80 >> i)))
+ continue;
+ chpid.id = sch->schib.pmcw.chpid[i];
+ chp = chpid_to_chp(chpid);
+ if (!chp)
+ continue;
+
+ mutex_lock(&chp->lock);
+ if (!chp->desc_fmt1.f) {
+ mutex_unlock(&chp->lock);
+ return 0;
+ }
+ if (!chp->desc_fmt1.r)
+ mdc = 1;
+ mdc = mdc ? min_t(int, mdc, chp->desc_fmt1.mdc) :
+ chp->desc_fmt1.mdc;
+ mutex_unlock(&chp->lock);
+ }
+
+ return mdc;
+}
+EXPORT_SYMBOL(ccw_device_get_mdc);
+
+/**
+ * ccw_device_tm_intrg - perform interrogate function
+ * @cdev: ccw device on which to perform the interrogate function
+ *
+ * Perform an interrogate function on the given ccw device. Return zero on
+ * success, non-zero otherwise.
+ */
+int ccw_device_tm_intrg(struct ccw_device *cdev)
+{
+ struct subchannel *sch = to_subchannel(cdev->dev.parent);
+
+ if (!sch->schib.pmcw.ena)
+ return -EINVAL;
+ if (cdev->private->state != DEV_STATE_ONLINE)
+ return -EIO;
+ if (!scsw_is_tm(&sch->schib.scsw) ||
+ !(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_START_PEND))
+ return -EINVAL;
+ return cio_tm_intrg(sch);
+}
+EXPORT_SYMBOL(ccw_device_tm_intrg);
+
+/**
+ * ccw_device_get_schid - obtain a subchannel id
+ * @cdev: device to obtain the id for
+ * @schid: where to fill in the values
+ */
+void ccw_device_get_schid(struct ccw_device *cdev, struct subchannel_id *schid)
+{
+ struct subchannel *sch = to_subchannel(cdev->dev.parent);
+
+ *schid = sch->schid;
+}
+EXPORT_SYMBOL_GPL(ccw_device_get_schid);
+
+MODULE_LICENSE("GPL");
+EXPORT_SYMBOL(ccw_device_set_options_mask);
+EXPORT_SYMBOL(ccw_device_set_options);
+EXPORT_SYMBOL(ccw_device_clear_options);
+EXPORT_SYMBOL(ccw_device_clear);
+EXPORT_SYMBOL(ccw_device_halt);
+EXPORT_SYMBOL(ccw_device_resume);
+EXPORT_SYMBOL(ccw_device_start_timeout);
+EXPORT_SYMBOL(ccw_device_start);
+EXPORT_SYMBOL(ccw_device_start_timeout_key);
+EXPORT_SYMBOL(ccw_device_start_key);
+EXPORT_SYMBOL(ccw_device_get_ciw);
+EXPORT_SYMBOL(ccw_device_get_path_mask);
+EXPORT_SYMBOL_GPL(ccw_device_get_chp_desc);