xref: /openbmc/linux/arch/s390/include/uapi/asm/cmb.h (revision 4f6cce39)
1 #ifndef _UAPIS390_CMB_H
2 #define _UAPIS390_CMB_H
3 
4 #include <linux/types.h>
5 
6 /**
7  * struct cmbdata - channel measurement block data for user space
8  * @size: size of the stored data
9  * @elapsed_time: time since last sampling
10  * @ssch_rsch_count: number of ssch and rsch
11  * @sample_count: number of samples
12  * @device_connect_time: time of device connect
13  * @function_pending_time: time of function pending
14  * @device_disconnect_time: time of device disconnect
15  * @control_unit_queuing_time: time of control unit queuing
16  * @device_active_only_time: time of device active only
17  * @device_busy_time: time of device busy (ext. format)
18  * @initial_command_response_time: initial command response time (ext. format)
19  *
20  * All values are stored as 64 bit for simplicity, especially
21  * in 32 bit emulation mode. All time values are normalized to
22  * nanoseconds.
23  * Currently, two formats are known, which differ by the size of
24  * this structure, i.e. the last two members are only set when
25  * the extended channel measurement facility (first shipped in
26  * z990 machines) is activated.
27  * Potentially, more fields could be added, which would result in a
28  * new ioctl number.
29  */
30 struct cmbdata {
31 	__u64 size;
32 	__u64 elapsed_time;
33  /* basic and exended format: */
34 	__u64 ssch_rsch_count;
35 	__u64 sample_count;
36 	__u64 device_connect_time;
37 	__u64 function_pending_time;
38 	__u64 device_disconnect_time;
39 	__u64 control_unit_queuing_time;
40 	__u64 device_active_only_time;
41  /* extended format only: */
42 	__u64 device_busy_time;
43 	__u64 initial_command_response_time;
44 };
45 
46 /* enable channel measurement */
47 #define BIODASDCMFENABLE	_IO(DASD_IOCTL_LETTER, 32)
48 /* enable channel measurement */
49 #define BIODASDCMFDISABLE	_IO(DASD_IOCTL_LETTER, 33)
50 /* read channel measurement data */
51 #define BIODASDREADALLCMB	_IOWR(DASD_IOCTL_LETTER, 33, struct cmbdata)
52 
53 #endif /* _UAPIS390_CMB_H */
54