xref: /openbmc/linux/arch/s390/include/asm/vdso.h (revision 5a5525b0)
1b2441318SGreg Kroah-Hartman /* SPDX-License-Identifier: GPL-2.0 */
2b020632eSMartin Schwidefsky #ifndef __S390_VDSO_H__
3b020632eSMartin Schwidefsky #define __S390_VDSO_H__
4b020632eSMartin Schwidefsky 
5b020632eSMartin Schwidefsky /* Default link addresses for the vDSOs */
6b020632eSMartin Schwidefsky #define VDSO32_LBASE	0
7b020632eSMartin Schwidefsky #define VDSO64_LBASE	0
8b020632eSMartin Schwidefsky 
913c6680aSMartin Schwidefsky #define VDSO_VERSION_STRING	LINUX_2.6.29
10b020632eSMartin Schwidefsky 
11b020632eSMartin Schwidefsky #ifndef __ASSEMBLY__
12b020632eSMartin Schwidefsky 
13b020632eSMartin Schwidefsky /*
14c742b31cSMartin Schwidefsky  * Note about the vdso_data and vdso_per_cpu_data structures:
15b020632eSMartin Schwidefsky  *
16c742b31cSMartin Schwidefsky  * NEVER USE THEM IN USERSPACE CODE DIRECTLY. The layout of the
17b020632eSMartin Schwidefsky  * structure is supposed to be known only to the function in the vdso
18b020632eSMartin Schwidefsky  * itself and may change without notice.
19b020632eSMartin Schwidefsky  */
20b020632eSMartin Schwidefsky 
21b020632eSMartin Schwidefsky struct vdso_data {
22b020632eSMartin Schwidefsky 	__u64 tb_update_count;		/* Timebase atomicity ctr	0x00 */
23b020632eSMartin Schwidefsky 	__u64 xtime_tod_stamp;		/* TOD clock for xtime		0x08 */
24b020632eSMartin Schwidefsky 	__u64 xtime_clock_sec;		/* Kernel time			0x10 */
25b020632eSMartin Schwidefsky 	__u64 xtime_clock_nsec;		/*				0x18 */
26b7eacb59SMartin Schwidefsky 	__u64 xtime_coarse_sec;		/* Coarse kernel time		0x20 */
27b7eacb59SMartin Schwidefsky 	__u64 xtime_coarse_nsec;	/*				0x28 */
28b7eacb59SMartin Schwidefsky 	__u64 wtom_clock_sec;		/* Wall to monotonic clock	0x30 */
29b7eacb59SMartin Schwidefsky 	__u64 wtom_clock_nsec;		/*				0x38 */
30b7eacb59SMartin Schwidefsky 	__u64 wtom_coarse_sec;		/* Coarse wall to monotonic	0x40 */
31b7eacb59SMartin Schwidefsky 	__u64 wtom_coarse_nsec;		/*				0x48 */
32b7eacb59SMartin Schwidefsky 	__u32 tz_minuteswest;		/* Minutes west of Greenwich	0x50 */
33b7eacb59SMartin Schwidefsky 	__u32 tz_dsttime;		/* Type of dst correction	0x54 */
34b7eacb59SMartin Schwidefsky 	__u32 ectg_available;		/* ECTG instruction present	0x58 */
35b7eacb59SMartin Schwidefsky 	__u32 tk_mult;			/* Mult. used for xtime_nsec	0x5c */
36b7eacb59SMartin Schwidefsky 	__u32 tk_shift;			/* Shift used for xtime_nsec	0x60 */
3775c7b6f3SMartin Schwidefsky 	__u32 ts_dir;			/* TOD steering direction	0x64 */
3875c7b6f3SMartin Schwidefsky 	__u64 ts_end;			/* TOD steering end		0x68 */
39c742b31cSMartin Schwidefsky };
40c742b31cSMartin Schwidefsky 
41c742b31cSMartin Schwidefsky struct vdso_per_cpu_data {
42c742b31cSMartin Schwidefsky 	__u64 ectg_timer_base;
43c742b31cSMartin Schwidefsky 	__u64 ectg_user_time;
445a5525b0SHeiko Carstens 	/*
455a5525b0SHeiko Carstens 	 * Note: node_id and cpu_nr must be at adjacent memory locations.
465a5525b0SHeiko Carstens 	 * VDSO userspace must read both values with a single instruction.
475a5525b0SHeiko Carstens 	 */
485a5525b0SHeiko Carstens 	union {
495a5525b0SHeiko Carstens 		__u64 getcpu_val;
505a5525b0SHeiko Carstens 		struct {
51249c543bSMartin Schwidefsky 			__u32 node_id;
525a5525b0SHeiko Carstens 			__u32 cpu_nr;
535a5525b0SHeiko Carstens 		};
545a5525b0SHeiko Carstens 	};
55b020632eSMartin Schwidefsky };
56b020632eSMartin Schwidefsky 
57b020632eSMartin Schwidefsky extern struct vdso_data *vdso_data;
583c6153e8SHeiko Carstens extern struct vdso_data boot_vdso_data;
59b020632eSMartin Schwidefsky 
60608796ffSMartin Schwidefsky void vdso_alloc_boot_cpu(struct lowcore *lowcore);
61c667aeacSHeiko Carstens int vdso_alloc_per_cpu(struct lowcore *lowcore);
62c667aeacSHeiko Carstens void vdso_free_per_cpu(struct lowcore *lowcore);
63c742b31cSMartin Schwidefsky 
64b020632eSMartin Schwidefsky #endif /* __ASSEMBLY__ */
65b020632eSMartin Schwidefsky #endif /* __S390_VDSO_H__ */
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