hc
2024-10-12 a5969cabbb4660eab42b6ef0412cbbd1200cf14d
kernel/arch/x86/include/asm/fpu/xstate.h
....@@ -2,9 +2,11 @@
22 #ifndef __ASM_X86_XSAVE_H
33 #define __ASM_X86_XSAVE_H
44
5
-#include <linux/types.h>
6
-#include <asm/processor.h>
75 #include <linux/uaccess.h>
6
+#include <linux/types.h>
7
+
8
+#include <asm/processor.h>
9
+#include <asm/user.h>
810
911 /* Bit 63 of XCR0 is reserved for future expansion */
1012 #define XFEATURE_MASK_EXTEND (~(XFEATURE_MASK_FPSSE | (1ULL << 63)))
....@@ -19,19 +21,53 @@
1921 #define XSAVE_YMM_SIZE 256
2022 #define XSAVE_YMM_OFFSET (XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET)
2123
22
-/* Supervisor features */
23
-#define XFEATURE_MASK_SUPERVISOR (XFEATURE_MASK_PT)
24
+#define XSAVE_ALIGNMENT 64
2425
25
-/* All currently supported features */
26
-#define XCNTXT_MASK (XFEATURE_MASK_FP | \
27
- XFEATURE_MASK_SSE | \
28
- XFEATURE_MASK_YMM | \
29
- XFEATURE_MASK_OPMASK | \
30
- XFEATURE_MASK_ZMM_Hi256 | \
31
- XFEATURE_MASK_Hi16_ZMM | \
32
- XFEATURE_MASK_PKRU | \
33
- XFEATURE_MASK_BNDREGS | \
34
- XFEATURE_MASK_BNDCSR)
26
+/* All currently supported user features */
27
+#define XFEATURE_MASK_USER_SUPPORTED (XFEATURE_MASK_FP | \
28
+ XFEATURE_MASK_SSE | \
29
+ XFEATURE_MASK_YMM | \
30
+ XFEATURE_MASK_OPMASK | \
31
+ XFEATURE_MASK_ZMM_Hi256 | \
32
+ XFEATURE_MASK_Hi16_ZMM | \
33
+ XFEATURE_MASK_PKRU | \
34
+ XFEATURE_MASK_BNDREGS | \
35
+ XFEATURE_MASK_BNDCSR)
36
+
37
+/* All currently supported supervisor features */
38
+#define XFEATURE_MASK_SUPERVISOR_SUPPORTED (XFEATURE_MASK_PASID)
39
+
40
+/*
41
+ * A supervisor state component may not always contain valuable information,
42
+ * and its size may be huge. Saving/restoring such supervisor state components
43
+ * at each context switch can cause high CPU and space overhead, which should
44
+ * be avoided. Such supervisor state components should only be saved/restored
45
+ * on demand. The on-demand dynamic supervisor features are set in this mask.
46
+ *
47
+ * Unlike the existing supported supervisor features, a dynamic supervisor
48
+ * feature does not allocate a buffer in task->fpu, and the corresponding
49
+ * supervisor state component cannot be saved/restored at each context switch.
50
+ *
51
+ * To support a dynamic supervisor feature, a developer should follow the
52
+ * dos and don'ts as below:
53
+ * - Do dynamically allocate a buffer for the supervisor state component.
54
+ * - Do manually invoke the XSAVES/XRSTORS instruction to save/restore the
55
+ * state component to/from the buffer.
56
+ * - Don't set the bit corresponding to the dynamic supervisor feature in
57
+ * IA32_XSS at run time, since it has been set at boot time.
58
+ */
59
+#define XFEATURE_MASK_DYNAMIC (XFEATURE_MASK_LBR)
60
+
61
+/*
62
+ * Unsupported supervisor features. When a supervisor feature in this mask is
63
+ * supported in the future, move it to the supported supervisor feature mask.
64
+ */
65
+#define XFEATURE_MASK_SUPERVISOR_UNSUPPORTED (XFEATURE_MASK_PT)
66
+
67
+/* All supervisor states including supported and unsupported states. */
68
+#define XFEATURE_MASK_SUPERVISOR_ALL (XFEATURE_MASK_SUPERVISOR_SUPPORTED | \
69
+ XFEATURE_MASK_DYNAMIC | \
70
+ XFEATURE_MASK_SUPERVISOR_UNSUPPORTED)
3571
3672 #ifdef CONFIG_X86_64
3773 #define REX_PREFIX "0x48, "
....@@ -39,22 +75,45 @@
3975 #define REX_PREFIX
4076 #endif
4177
42
-extern u64 xfeatures_mask;
78
+extern u64 xfeatures_mask_all;
79
+
80
+static inline u64 xfeatures_mask_supervisor(void)
81
+{
82
+ return xfeatures_mask_all & XFEATURE_MASK_SUPERVISOR_SUPPORTED;
83
+}
84
+
85
+static inline u64 xfeatures_mask_user(void)
86
+{
87
+ return xfeatures_mask_all & XFEATURE_MASK_USER_SUPPORTED;
88
+}
89
+
90
+static inline u64 xfeatures_mask_dynamic(void)
91
+{
92
+ if (!boot_cpu_has(X86_FEATURE_ARCH_LBR))
93
+ return XFEATURE_MASK_DYNAMIC & ~XFEATURE_MASK_LBR;
94
+
95
+ return XFEATURE_MASK_DYNAMIC;
96
+}
97
+
4398 extern u64 xstate_fx_sw_bytes[USER_XSTATE_FX_SW_WORDS];
4499
45100 extern void __init update_regset_xstate_info(unsigned int size,
46101 u64 xstate_mask);
47102
48
-void fpu__xstate_clear_all_cpu_caps(void);
49
-void *get_xsave_addr(struct xregs_state *xsave, int xstate);
50
-const void *get_xsave_field_ptr(int xstate_field);
103
+void *get_xsave_addr(struct xregs_state *xsave, int xfeature_nr);
104
+const void *get_xsave_field_ptr(int xfeature_nr);
51105 int using_compacted_format(void);
52
-int copy_xstate_to_kernel(void *kbuf, struct xregs_state *xsave, unsigned int offset, unsigned int size);
53
-int copy_xstate_to_user(void __user *ubuf, struct xregs_state *xsave, unsigned int offset, unsigned int size);
106
+int xfeature_size(int xfeature_nr);
107
+struct membuf;
108
+void copy_xstate_to_kernel(struct membuf to, struct xregs_state *xsave);
54109 int copy_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf);
55110 int copy_user_to_xstate(struct xregs_state *xsave, const void __user *ubuf);
111
+void copy_supervisor_to_kernel(struct xregs_state *xsave);
112
+void copy_dynamic_supervisor_to_kernel(struct xregs_state *xstate, u64 mask);
113
+void copy_kernel_to_dynamic_supervisor(struct xregs_state *xstate, u64 mask);
114
+
56115
57116 /* Validate an xstate header supplied by userspace (ptrace or sigreturn) */
58
-extern int validate_xstate_header(const struct xstate_header *hdr);
117
+int validate_user_xstate_header(const struct xstate_header *hdr);
59118
60119 #endif