1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __ASM_X86_XSAVE_H
3#define __ASM_X86_XSAVE_H
4
5#include <linux/uaccess.h>
6#include <linux/types.h>
7
8#include <asm/processor.h>
9#include <asm/user.h>
10
11/* Bit 63 of XCR0 is reserved for future expansion */
12#define XFEATURE_MASK_EXTEND	(~(XFEATURE_MASK_FPSSE | (1ULL << 63)))
13
14#define XSTATE_CPUID		0x0000000d
15
16#define FXSAVE_SIZE	512
17
18#define XSAVE_HDR_SIZE	    64
19#define XSAVE_HDR_OFFSET    FXSAVE_SIZE
20
21#define XSAVE_YMM_SIZE	    256
22#define XSAVE_YMM_OFFSET    (XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET)
23
24#define XSAVE_ALIGNMENT     64
25
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)
71
72#ifdef CONFIG_X86_64
73#define REX_PREFIX	"0x48, "
74#else
75#define REX_PREFIX
76#endif
77
78extern u64 xfeatures_mask_all;
79
80static inline u64 xfeatures_mask_supervisor(void)
81{
82	return xfeatures_mask_all & XFEATURE_MASK_SUPERVISOR_SUPPORTED;
83}
84
85static inline u64 xfeatures_mask_user(void)
86{
87	return xfeatures_mask_all & XFEATURE_MASK_USER_SUPPORTED;
88}
89
90static 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
98extern u64 xstate_fx_sw_bytes[USER_XSTATE_FX_SW_WORDS];
99
100extern void __init update_regset_xstate_info(unsigned int size,
101					     u64 xstate_mask);
102
103void *get_xsave_addr(struct xregs_state *xsave, int xfeature_nr);
104const void *get_xsave_field_ptr(int xfeature_nr);
105int using_compacted_format(void);
106int xfeature_size(int xfeature_nr);
107struct membuf;
108void copy_xstate_to_kernel(struct membuf to, struct xregs_state *xsave);
109int copy_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf);
110int copy_user_to_xstate(struct xregs_state *xsave, const void __user *ubuf);
111void copy_supervisor_to_kernel(struct xregs_state *xsave);
112void copy_dynamic_supervisor_to_kernel(struct xregs_state *xstate, u64 mask);
113void copy_kernel_to_dynamic_supervisor(struct xregs_state *xstate, u64 mask);
114
115
116/* Validate an xstate header supplied by userspace (ptrace or sigreturn) */
117int validate_user_xstate_header(const struct xstate_header *hdr);
118
119#endif
120