arch/s390/include/uapi/asm/cmb.h

   1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
   2 #ifndef _UAPIS390_CMB_H
   3 #define _UAPIS390_CMB_H
   4
   5 #include <linux/types.h>
   6
   7 /**
   8  * struct cmbdata - channel measurement block data for user space
   9  * @size: size of the stored data
  10  * @elapsed_time: time since last sampling
  11  * @ssch_rsch_count: number of ssch and rsch
  12  * @sample_count: number of samples
  13  * @device_connect_time: time of device connect
  14  * @function_pending_time: time of function pending
  15  * @device_disconnect_time: time of device disconnect
  16  * @control_unit_queuing_time: time of control unit queuing
  17  * @device_active_only_time: time of device active only
  18  * @device_busy_time: time of device busy (ext. format)
  19  * @initial_command_response_time: initial command response time (ext. format)
  20  *
  21  * All values are stored as 64 bit for simplicity, especially
  22  * in 32 bit emulation mode. All time values are normalized to
  23  * nanoseconds.
  24  * Currently, two formats are known, which differ by the size of
  25  * this structure, i.e. the last two members are only set when
  26  * the extended channel measurement facility (first shipped in
  27  * z990 machines) is activated.
  28  * Potentially, more fields could be added, which would result in a
  29  * new ioctl number.
  30  */
  31 struct cmbdata {
  32         __u64 size;
  33         __u64 elapsed_time;
  34  /* basic and exended format: */
  35         __u64 ssch_rsch_count;
  36         __u64 sample_count;
  37         __u64 device_connect_time;
  38         __u64 function_pending_time;
  39         __u64 device_disconnect_time;
  40         __u64 control_unit_queuing_time;
  41         __u64 device_active_only_time;
  42  /* extended format only: */
  43         __u64 device_busy_time;
  44         __u64 initial_command_response_time;
  45 };
  46
  47 /* enable channel measurement */
  48 #define BIODASDCMFENABLE        _IO(DASD_IOCTL_LETTER, 32)
  49 /* enable channel measurement */
  50 #define BIODASDCMFDISABLE       _IO(DASD_IOCTL_LETTER, 33)
  51 /* read channel measurement data */
  52 #define BIODASDREADALLCMB       _IOWR(DASD_IOCTL_LETTER, 33, struct cmbdata)
  53
  54 #endif /* _UAPIS390_CMB_H */