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-rw-r--r--arch/x86/include/asm/user.h64
1 files changed, 64 insertions, 0 deletions
diff --git a/arch/x86/include/asm/user.h b/arch/x86/include/asm/user.h
new file mode 100644
index 000000000..413c91746
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+++ b/arch/x86/include/asm/user.h
@@ -0,0 +1,64 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_X86_USER_H
+#define _ASM_X86_USER_H
+
+#ifdef CONFIG_X86_32
+# include <asm/user_32.h>
+#else
+# include <asm/user_64.h>
+#endif
+
+#include <asm/types.h>
+
+struct user_ymmh_regs {
+ /* 16 * 16 bytes for each YMMH-reg */
+ __u32 ymmh_space[64];
+};
+
+struct user_xstate_header {
+ __u64 xfeatures;
+ __u64 reserved1[2];
+ __u64 reserved2[5];
+};
+
+/*
+ * The structure layout of user_xstateregs, used for exporting the
+ * extended register state through ptrace and core-dump (NT_X86_XSTATE note)
+ * interfaces will be same as the memory layout of xsave used by the processor
+ * (except for the bytes 464..511, which can be used by the software) and hence
+ * the size of this structure varies depending on the features supported by the
+ * processor and OS. The size of the structure that users need to use can be
+ * obtained by doing:
+ * cpuid_count(0xd, 0, &eax, &ptrace_xstateregs_struct_size, &ecx, &edx);
+ * i.e., cpuid.(eax=0xd,ecx=0).ebx will be the size that user (debuggers, etc.)
+ * need to use.
+ *
+ * For now, only the first 8 bytes of the software usable bytes[464..471] will
+ * be used and will be set to OS enabled xstate mask (which is same as the
+ * 64bit mask returned by the xgetbv's xCR0). Users (analyzing core dump
+ * remotely, etc.) can use this mask as well as the mask saved in the
+ * xstate_hdr bytes and interpret what states the processor/OS supports
+ * and what states are in modified/initialized conditions for the
+ * particular process/thread.
+ *
+ * Also when the user modifies certain state FP/SSE/etc through the
+ * ptrace interface, they must ensure that the header.xfeatures
+ * bytes[512..519] of the memory layout are updated correspondingly.
+ * i.e., for example when FP state is modified to a non-init state,
+ * header.xfeatures's bit 0 must be set to '1', when SSE is modified to
+ * non-init state, header.xfeatures's bit 1 must to be set to '1', etc.
+ */
+#define USER_XSTATE_FX_SW_WORDS 6
+#define USER_XSTATE_XCR0_WORD 0
+
+struct user_xstateregs {
+ struct {
+ __u64 fpx_space[58];
+ __u64 xstate_fx_sw[USER_XSTATE_FX_SW_WORDS];
+ } i387;
+ struct user_xstate_header header;
+ struct user_ymmh_regs ymmh;
+ /* further processor state extensions go here */
+};
+
+#endif /* _ASM_X86_USER_H */