1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | #ifndef _ASM_X86_SPECCTRL_H_ |
3 | #define _ASM_X86_SPECCTRL_H_ |
4 | |
5 | #include <linux/thread_info.h> |
6 | #include <asm/nospec-branch.h> |
7 | |
8 | /* |
9 | * On VMENTER we must preserve whatever view of the SPEC_CTRL MSR |
10 | * the guest has, while on VMEXIT we restore the host view. This |
11 | * would be easier if SPEC_CTRL were architecturally maskable or |
12 | * shadowable for guests but this is not (currently) the case. |
13 | * Takes the guest view of SPEC_CTRL MSR as a parameter and also |
14 | * the guest's version of VIRT_SPEC_CTRL, if emulated. |
15 | */ |
16 | extern void x86_virt_spec_ctrl(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl, bool guest); |
17 | |
18 | /** |
19 | * x86_spec_ctrl_set_guest - Set speculation control registers for the guest |
20 | * @guest_spec_ctrl: The guest content of MSR_SPEC_CTRL |
21 | * @guest_virt_spec_ctrl: The guest controlled bits of MSR_VIRT_SPEC_CTRL |
22 | * (may get translated to MSR_AMD64_LS_CFG bits) |
23 | * |
24 | * Avoids writing to the MSR if the content/bits are the same |
25 | */ |
26 | static inline |
27 | void x86_spec_ctrl_set_guest(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl) |
28 | { |
29 | x86_virt_spec_ctrl(guest_spec_ctrl, guest_virt_spec_ctrl, true); |
30 | } |
31 | |
32 | /** |
33 | * x86_spec_ctrl_restore_host - Restore host speculation control registers |
34 | * @guest_spec_ctrl: The guest content of MSR_SPEC_CTRL |
35 | * @guest_virt_spec_ctrl: The guest controlled bits of MSR_VIRT_SPEC_CTRL |
36 | * (may get translated to MSR_AMD64_LS_CFG bits) |
37 | * |
38 | * Avoids writing to the MSR if the content/bits are the same |
39 | */ |
40 | static inline |
41 | void x86_spec_ctrl_restore_host(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl) |
42 | { |
43 | x86_virt_spec_ctrl(guest_spec_ctrl, guest_virt_spec_ctrl, false); |
44 | } |
45 | |
46 | /* AMD specific Speculative Store Bypass MSR data */ |
47 | extern u64 x86_amd_ls_cfg_base; |
48 | extern u64 x86_amd_ls_cfg_ssbd_mask; |
49 | |
50 | static inline u64 ssbd_tif_to_spec_ctrl(u64 tifn) |
51 | { |
52 | BUILD_BUG_ON(TIF_SSBD < SPEC_CTRL_SSBD_SHIFT); |
53 | return (tifn & _TIF_SSBD) >> (TIF_SSBD - SPEC_CTRL_SSBD_SHIFT); |
54 | } |
55 | |
56 | static inline u64 stibp_tif_to_spec_ctrl(u64 tifn) |
57 | { |
58 | BUILD_BUG_ON(TIF_SPEC_IB < SPEC_CTRL_STIBP_SHIFT); |
59 | return (tifn & _TIF_SPEC_IB) >> (TIF_SPEC_IB - SPEC_CTRL_STIBP_SHIFT); |
60 | } |
61 | |
62 | static inline unsigned long ssbd_spec_ctrl_to_tif(u64 spec_ctrl) |
63 | { |
64 | BUILD_BUG_ON(TIF_SSBD < SPEC_CTRL_SSBD_SHIFT); |
65 | return (spec_ctrl & SPEC_CTRL_SSBD) << (TIF_SSBD - SPEC_CTRL_SSBD_SHIFT); |
66 | } |
67 | |
68 | static inline unsigned long stibp_spec_ctrl_to_tif(u64 spec_ctrl) |
69 | { |
70 | BUILD_BUG_ON(TIF_SPEC_IB < SPEC_CTRL_STIBP_SHIFT); |
71 | return (spec_ctrl & SPEC_CTRL_STIBP) << (TIF_SPEC_IB - SPEC_CTRL_STIBP_SHIFT); |
72 | } |
73 | |
74 | static inline u64 ssbd_tif_to_amd_ls_cfg(u64 tifn) |
75 | { |
76 | return (tifn & _TIF_SSBD) ? x86_amd_ls_cfg_ssbd_mask : 0ULL; |
77 | } |
78 | |
79 | #ifdef CONFIG_SMP |
80 | extern void speculative_store_bypass_ht_init(void); |
81 | #else |
82 | static inline void speculative_store_bypass_ht_init(void) { } |
83 | #endif |
84 | |
85 | extern void speculation_ctrl_update(unsigned long tif); |
86 | extern void speculation_ctrl_update_current(void); |
87 | |
88 | #endif |
89 | |