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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.c241
1 files changed, 211 insertions, 30 deletions
diff --git a/drivers/s390/cio/device_ops.c b/drivers/s390/cio/device_ops.c
index 14eba854b15..7fd2dadc329 100644
--- a/drivers/s390/cio/device_ops.c
+++ b/drivers/s390/cio/device_ops.c
@@ -25,6 +25,16 @@
#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)
{
/*
@@ -40,6 +50,15 @@ int ccw_device_set_options_mask(struct ccw_device *cdev, unsigned long flags)
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)
{
/*
@@ -59,6 +78,13 @@ int ccw_device_set_options(struct ccw_device *cdev, unsigned long flags)
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;
@@ -67,8 +93,22 @@ void ccw_device_clear_options(struct ccw_device *cdev, unsigned long flags)
cdev->private->options.force &= (flags & CCWDEV_ALLOW_FORCE) == 0;
}
-int
-ccw_device_clear(struct ccw_device *cdev, unsigned long intparm)
+/**
+ * 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;
@@ -89,10 +129,33 @@ ccw_device_clear(struct ccw_device *cdev, unsigned long intparm)
return ret;
}
-int
-ccw_device_start_key(struct ccw_device *cdev, struct ccw1 *cpa,
- unsigned long intparm, __u8 lpm, __u8 key,
- unsigned long flags)
+/**
+ * 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;
@@ -135,11 +198,38 @@ ccw_device_start_key(struct ccw_device *cdev, struct ccw1 *cpa,
return ret;
}
-
-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)
+/**
+ * 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;
@@ -152,18 +242,67 @@ ccw_device_start_timeout_key(struct ccw_device *cdev, struct ccw1 *cpa,
return ret;
}
-int
-ccw_device_start(struct ccw_device *cdev, struct ccw1 *cpa,
- unsigned long intparm, __u8 lpm, unsigned long flags)
+/**
+ * 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);
}
-int
-ccw_device_start_timeout(struct ccw_device *cdev, struct ccw1 *cpa,
- unsigned long intparm, __u8 lpm, unsigned long flags,
- int expires)
+/**
+ * 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,
@@ -171,8 +310,23 @@ ccw_device_start_timeout(struct ccw_device *cdev, struct ccw1 *cpa,
}
-int
-ccw_device_halt(struct ccw_device *cdev, unsigned long intparm)
+/**
+ * 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;
@@ -193,8 +347,20 @@ ccw_device_halt(struct ccw_device *cdev, unsigned long intparm)
return ret;
}
-int
-ccw_device_resume(struct ccw_device *cdev)
+/**
+ * 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;
@@ -260,11 +426,21 @@ ccw_device_call_handler(struct ccw_device *cdev)
return 1;
}
-/*
- * Search for CIW command in extended sense data.
+/**
+ * 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)
+struct ciw *ccw_device_get_ciw(struct ccw_device *cdev, __u32 ct)
{
int ciw_cnt;
@@ -276,8 +452,14 @@ ccw_device_get_ciw(struct ccw_device *cdev, __u32 ct)
return NULL;
}
-__u8
-ccw_device_get_path_mask(struct ccw_device *cdev)
+/**
+ * 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;
@@ -357,8 +539,7 @@ out_unlock:
return ret;
}
-void *
-ccw_device_get_chp_desc(struct ccw_device *cdev, int chp_no)
+void *ccw_device_get_chp_desc(struct ccw_device *cdev, int chp_no)
{
struct subchannel *sch;
struct chp_id chpid;