linux-hardened/include/asm-s390/cmb.h
Cornelia Huck 94bb063312 [S390] rework of channel measurement facility.
Fixes for several channel measurement facility bugs:
* Blocks copied from the hardware might not be consistent. Solve this
  by moving the copying into idle state and repeating the copying.
* avg_sample_interval changed with every read, even though no new block
  was available. Solve this by storing a timestamp when the last new
  block was received.
* Several locking issues.
* Measurements were not reenabled after a disconnected device became
  available again.
* Remove #defines for ioctls that were never implemented.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-06-29 15:08:41 +02:00

94 lines
2.6 KiB
C

#ifndef S390_CMB_H
#define S390_CMB_H
/**
* struct cmbdata -- channel measurement block data for user space
*
* @size: size of the stored data
* @ssch_rsch_count: XXX
* @sample_count:
* @device_connect_time:
* @function_pending_time:
* @device_disconnect_time:
* @control_unit_queuing_time:
* @device_active_only_time:
* @device_busy_time:
* @initial_command_response_time:
*
* all values are stored as 64 bit for simplicity, especially
* in 32 bit emulation mode. All time values are normalized to
* nanoseconds.
* Currently, two formats are known, which differ by the size of
* this structure, i.e. the last two members are only set when
* the extended channel measurement facility (first shipped in
* z990 machines) is activated.
* Potentially, more fields could be added, which results in a
* new ioctl number.
**/
struct cmbdata {
__u64 size;
__u64 elapsed_time;
/* basic and exended format: */
__u64 ssch_rsch_count;
__u64 sample_count;
__u64 device_connect_time;
__u64 function_pending_time;
__u64 device_disconnect_time;
__u64 control_unit_queuing_time;
__u64 device_active_only_time;
/* extended format only: */
__u64 device_busy_time;
__u64 initial_command_response_time;
};
/* enable channel measurement */
#define BIODASDCMFENABLE _IO(DASD_IOCTL_LETTER,32)
/* enable channel measurement */
#define BIODASDCMFDISABLE _IO(DASD_IOCTL_LETTER,33)
/* read channel measurement data */
#define BIODASDREADALLCMB _IOWR(DASD_IOCTL_LETTER,33,struct cmbdata)
#ifdef __KERNEL__
struct ccw_device;
/**
* enable_cmf() - switch on the channel measurement for a specific device
* @cdev: The ccw device to be enabled
* returns 0 for success or a negative error value.
*
* Context:
* non-atomic
**/
extern int enable_cmf(struct ccw_device *cdev);
/**
* disable_cmf() - switch off the channel measurement for a specific device
* @cdev: The ccw device to be disabled
* returns 0 for success or a negative error value.
*
* Context:
* non-atomic
**/
extern int disable_cmf(struct ccw_device *cdev);
/**
* cmf_read() - read one value from the current channel measurement block
* @cmf: the channel to be read
* @index: the name of the value that is read
*
* Context:
* any
**/
extern u64 cmf_read(struct ccw_device *cdev, int index);
/**
* cmf_readall() - read one value from the current channel measurement block
* @cmf: the channel to be read
* @data: a pointer to a data block that will be filled
*
* Context:
* any
**/
extern int cmf_readall(struct ccw_device *cdev, struct cmbdata*data);
extern void cmf_reset(struct ccw_device *cdev);
#endif /* __KERNEL__ */
#endif /* S390_CMB_H */