xref: /linux/arch/x86/include/asm/xen/interface_64.h (revision 06d07429858317ded2db7986113a9e0129cd599b)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_X86_XEN_INTERFACE_64_H
3 #define _ASM_X86_XEN_INTERFACE_64_H
4 
5 /*
6  * 64-bit segment selectors
7  * These flat segments are in the Xen-private section of every GDT. Since these
8  * are also present in the initial GDT, many OSes will be able to avoid
9  * installing their own GDT.
10  */
11 
12 #define FLAT_RING3_CS32 0xe023  /* GDT index 260 */
13 #define FLAT_RING3_CS64 0xe033  /* GDT index 261 */
14 #define FLAT_RING3_DS32 0xe02b  /* GDT index 262 */
15 #define FLAT_RING3_DS64 0x0000  /* NULL selector */
16 #define FLAT_RING3_SS32 0xe02b  /* GDT index 262 */
17 #define FLAT_RING3_SS64 0xe02b  /* GDT index 262 */
18 
19 #define FLAT_KERNEL_DS64 FLAT_RING3_DS64
20 #define FLAT_KERNEL_DS32 FLAT_RING3_DS32
21 #define FLAT_KERNEL_DS   FLAT_KERNEL_DS64
22 #define FLAT_KERNEL_CS64 FLAT_RING3_CS64
23 #define FLAT_KERNEL_CS32 FLAT_RING3_CS32
24 #define FLAT_KERNEL_CS   FLAT_KERNEL_CS64
25 #define FLAT_KERNEL_SS64 FLAT_RING3_SS64
26 #define FLAT_KERNEL_SS32 FLAT_RING3_SS32
27 #define FLAT_KERNEL_SS   FLAT_KERNEL_SS64
28 
29 #define FLAT_USER_DS64 FLAT_RING3_DS64
30 #define FLAT_USER_DS32 FLAT_RING3_DS32
31 #define FLAT_USER_DS   FLAT_USER_DS64
32 #define FLAT_USER_CS64 FLAT_RING3_CS64
33 #define FLAT_USER_CS32 FLAT_RING3_CS32
34 #define FLAT_USER_CS   FLAT_USER_CS64
35 #define FLAT_USER_SS64 FLAT_RING3_SS64
36 #define FLAT_USER_SS32 FLAT_RING3_SS32
37 #define FLAT_USER_SS   FLAT_USER_SS64
38 
39 #define __HYPERVISOR_VIRT_START 0xFFFF800000000000
40 #define __HYPERVISOR_VIRT_END   0xFFFF880000000000
41 #define __MACH2PHYS_VIRT_START  0xFFFF800000000000
42 #define __MACH2PHYS_VIRT_END    0xFFFF804000000000
43 #define __MACH2PHYS_SHIFT       3
44 
45 /*
46  * int HYPERVISOR_set_segment_base(unsigned int which, unsigned long base)
47  *  @which == SEGBASE_*  ;  @base == 64-bit base address
48  * Returns 0 on success.
49  */
50 #define SEGBASE_FS          0
51 #define SEGBASE_GS_USER     1
52 #define SEGBASE_GS_KERNEL   2
53 #define SEGBASE_GS_USER_SEL 3 /* Set user %gs specified in base[15:0] */
54 
55 /*
56  * int HYPERVISOR_iret(void)
57  * All arguments are on the kernel stack, in the following format.
58  * Never returns if successful. Current kernel context is lost.
59  * The saved CS is mapped as follows:
60  *   RING0 -> RING3 kernel mode.
61  *   RING1 -> RING3 kernel mode.
62  *   RING2 -> RING3 kernel mode.
63  *   RING3 -> RING3 user mode.
64  * However RING0 indicates that the guest kernel should return to itself
65  * directly with
66  *      orb   $3,1*8(%rsp)
67  *      iretq
68  * If flags contains VGCF_in_syscall:
69  *   Restore RAX, RIP, RFLAGS, RSP.
70  *   Discard R11, RCX, CS, SS.
71  * Otherwise:
72  *   Restore RAX, R11, RCX, CS:RIP, RFLAGS, SS:RSP.
73  * All other registers are saved on hypercall entry and restored to user.
74  */
75 /* Guest exited in SYSCALL context? Return to guest with SYSRET? */
76 #define _VGCF_in_syscall 8
77 #define VGCF_in_syscall  (1<<_VGCF_in_syscall)
78 #define VGCF_IN_SYSCALL  VGCF_in_syscall
79 
80 #ifndef __ASSEMBLY__
81 
82 struct iret_context {
83     /* Top of stack (%rsp at point of hypercall). */
84     uint64_t rax, r11, rcx, flags, rip, cs, rflags, rsp, ss;
85     /* Bottom of iret stack frame. */
86 };
87 
88 #if defined(__GNUC__) && !defined(__STRICT_ANSI__)
89 /* Anonymous union includes both 32- and 64-bit names (e.g., eax/rax). */
90 #define __DECL_REG(name) union { \
91     uint64_t r ## name, e ## name; \
92     uint32_t _e ## name; \
93 }
94 #else
95 /* Non-gcc sources must always use the proper 64-bit name (e.g., rax). */
96 #define __DECL_REG(name) uint64_t r ## name
97 #endif
98 
99 struct cpu_user_regs {
100     uint64_t r15;
101     uint64_t r14;
102     uint64_t r13;
103     uint64_t r12;
104     __DECL_REG(bp);
105     __DECL_REG(bx);
106     uint64_t r11;
107     uint64_t r10;
108     uint64_t r9;
109     uint64_t r8;
110     __DECL_REG(ax);
111     __DECL_REG(cx);
112     __DECL_REG(dx);
113     __DECL_REG(si);
114     __DECL_REG(di);
115     uint32_t error_code;    /* private */
116     uint32_t entry_vector;  /* private */
117     __DECL_REG(ip);
118     uint16_t cs, _pad0[1];
119     uint8_t  saved_upcall_mask;
120     uint8_t  _pad1[3];
121     __DECL_REG(flags);      /* rflags.IF == !saved_upcall_mask */
122     __DECL_REG(sp);
123     uint16_t ss, _pad2[3];
124     uint16_t es, _pad3[3];
125     uint16_t ds, _pad4[3];
126     uint16_t fs, _pad5[3]; /* Non-zero => takes precedence over fs_base.     */
127     uint16_t gs, _pad6[3]; /* Non-zero => takes precedence over gs_base_usr. */
128 };
129 DEFINE_GUEST_HANDLE_STRUCT(cpu_user_regs);
130 
131 #undef __DECL_REG
132 
133 #define xen_pfn_to_cr3(pfn) ((unsigned long)(pfn) << 12)
134 #define xen_cr3_to_pfn(cr3) ((unsigned long)(cr3) >> 12)
135 
136 struct arch_vcpu_info {
137     unsigned long cr2;
138     unsigned long pad; /* sizeof(vcpu_info_t) == 64 */
139 };
140 
141 typedef unsigned long xen_callback_t;
142 
143 #define XEN_CALLBACK(__cs, __rip)				\
144 	((unsigned long)(__rip))
145 
146 #endif /* !__ASSEMBLY__ */
147 
148 
149 #endif /* _ASM_X86_XEN_INTERFACE_64_H */
150