xref: /openbmc/linux/arch/x86/include/asm/user.h (revision b96fc2f3)
1 #ifndef _ASM_X86_USER_H
2 #define _ASM_X86_USER_H
3 
4 #ifdef CONFIG_X86_32
5 # include <asm/user_32.h>
6 #else
7 # include <asm/user_64.h>
8 #endif
9 
10 #include <asm/types.h>
11 
12 struct user_ymmh_regs {
13 	/* 16 * 16 bytes for each YMMH-reg */
14 	__u32 ymmh_space[64];
15 };
16 
17 struct user_xstate_header {
18 	__u64 xfeatures;
19 	__u64 reserved1[2];
20 	__u64 reserved2[5];
21 };
22 
23 /*
24  * The structure layout of user_xstateregs, used for exporting the
25  * extended register state through ptrace and core-dump (NT_X86_XSTATE note)
26  * interfaces will be same as the memory layout of xsave used by the processor
27  * (except for the bytes 464..511, which can be used by the software) and hence
28  * the size of this structure varies depending on the features supported by the
29  * processor and OS. The size of the structure that users need to use can be
30  * obtained by doing:
31  *     cpuid_count(0xd, 0, &eax, &ptrace_xstateregs_struct_size, &ecx, &edx);
32  * i.e., cpuid.(eax=0xd,ecx=0).ebx will be the size that user (debuggers, etc.)
33  * need to use.
34  *
35  * For now, only the first 8 bytes of the software usable bytes[464..471] will
36  * be used and will be set to OS enabled xstate mask (which is same as the
37  * 64bit mask returned by the xgetbv's xCR0).  Users (analyzing core dump
38  * remotely, etc.) can use this mask as well as the mask saved in the
39  * xstate_hdr bytes and interpret what states the processor/OS supports
40  * and what states are in modified/initialized conditions for the
41  * particular process/thread.
42  *
43  * Also when the user modifies certain state FP/SSE/etc through the
44  * ptrace interface, they must ensure that the header.xfeatures
45  * bytes[512..519] of the memory layout are updated correspondingly.
46  * i.e., for example when FP state is modified to a non-init state,
47  * header.xfeatures's bit 0 must be set to '1', when SSE is modified to
48  * non-init state, header.xfeatures's bit 1 must to be set to '1', etc.
49  */
50 #define USER_XSTATE_FX_SW_WORDS 6
51 #define USER_XSTATE_XCR0_WORD	0
52 
53 struct user_xstateregs {
54 	struct {
55 		__u64 fpx_space[58];
56 		__u64 xstate_fx_sw[USER_XSTATE_FX_SW_WORDS];
57 	} i387;
58 	struct user_xstate_header header;
59 	struct user_ymmh_regs ymmh;
60 	/* further processor state extensions go here */
61 };
62 
63 #endif /* _ASM_X86_USER_H */
64