LXR linux/arch/x86/include/asm/user.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef _ASM_X86_USER_H
   3#define _ASM_X86_USER_H
   4
   5#ifdef CONFIG_X86_32
   6# include <asm/user_32.h>
   7#else
   8# include <asm/user_64.h>
   9#endif
  10
  11#include <asm/types.h>
  12
  13struct user_ymmh_regs {
  14        /* 16 * 16 bytes for each YMMH-reg */
  15        __u32 ymmh_space[64];
  16};
  17
  18struct user_xstate_header {
  19        __u64 xfeatures;
  20        __u64 reserved1[2];
  21        __u64 reserved2[5];
  22};
  23
  24/*
  25 * The structure layout of user_xstateregs, used for exporting the
  26 * extended register state through ptrace and core-dump (NT_X86_XSTATE note)
  27 * interfaces will be same as the memory layout of xsave used by the processor
  28 * (except for the bytes 464..511, which can be used by the software) and hence
  29 * the size of this structure varies depending on the features supported by the
  30 * processor and OS. The size of the structure that users need to use can be
  31 * obtained by doing:
  32 *     cpuid_count(0xd, 0, &eax, &ptrace_xstateregs_struct_size, &ecx, &edx);
  33 * i.e., cpuid.(eax=0xd,ecx=0).ebx will be the size that user (debuggers, etc.)
  34 * need to use.
  35 *
  36 * For now, only the first 8 bytes of the software usable bytes[464..471] will
  37 * be used and will be set to OS enabled xstate mask (which is same as the
  38 * 64bit mask returned by the xgetbv's xCR0).  Users (analyzing core dump
  39 * remotely, etc.) can use this mask as well as the mask saved in the
  40 * xstate_hdr bytes and interpret what states the processor/OS supports
  41 * and what states are in modified/initialized conditions for the
  42 * particular process/thread.
  43 *
  44 * Also when the user modifies certain state FP/SSE/etc through the
  45 * ptrace interface, they must ensure that the header.xfeatures
  46 * bytes[512..519] of the memory layout are updated correspondingly.
  47 * i.e., for example when FP state is modified to a non-init state,
  48 * header.xfeatures's bit 0 must be set to '1', when SSE is modified to
  49 * non-init state, header.xfeatures's bit 1 must to be set to '1', etc.
  50 */
  51#define USER_XSTATE_FX_SW_WORDS 6
  52#define USER_XSTATE_XCR0_WORD   0
  53
  54struct user_xstateregs {
  55        struct {
  56                __u64 fpx_space[58];
  57                __u64 xstate_fx_sw[USER_XSTATE_FX_SW_WORDS];
  58        } i387;
  59        struct user_xstate_header header;
  60        struct user_ymmh_regs ymmh;
  61        /* further processor state extensions go here */
  62};
  63
  64#endif /* _ASM_X86_USER_H */
  65