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 */
55