xref: /linux/arch/x86/include/asm/xen/interface_64.h (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
1 #ifndef _ASM_X86_XEN_INTERFACE_64_H
2 #define _ASM_X86_XEN_INTERFACE_64_H
3 
4 /*
5  * 64-bit segment selectors
6  * These flat segments are in the Xen-private section of every GDT. Since these
7  * are also present in the initial GDT, many OSes will be able to avoid
8  * installing their own GDT.
9  */
10 
11 #define FLAT_RING3_CS32 0xe023  /* GDT index 260 */
12 #define FLAT_RING3_CS64 0xe033  /* GDT index 261 */
13 #define FLAT_RING3_DS32 0xe02b  /* GDT index 262 */
14 #define FLAT_RING3_DS64 0x0000  /* NULL selector */
15 #define FLAT_RING3_SS32 0xe02b  /* GDT index 262 */
16 #define FLAT_RING3_SS64 0xe02b  /* GDT index 262 */
17 
18 #define FLAT_KERNEL_DS64 FLAT_RING3_DS64
19 #define FLAT_KERNEL_DS32 FLAT_RING3_DS32
20 #define FLAT_KERNEL_DS   FLAT_KERNEL_DS64
21 #define FLAT_KERNEL_CS64 FLAT_RING3_CS64
22 #define FLAT_KERNEL_CS32 FLAT_RING3_CS32
23 #define FLAT_KERNEL_CS   FLAT_KERNEL_CS64
24 #define FLAT_KERNEL_SS64 FLAT_RING3_SS64
25 #define FLAT_KERNEL_SS32 FLAT_RING3_SS32
26 #define FLAT_KERNEL_SS   FLAT_KERNEL_SS64
27 
28 #define FLAT_USER_DS64 FLAT_RING3_DS64
29 #define FLAT_USER_DS32 FLAT_RING3_DS32
30 #define FLAT_USER_DS   FLAT_USER_DS64
31 #define FLAT_USER_CS64 FLAT_RING3_CS64
32 #define FLAT_USER_CS32 FLAT_RING3_CS32
33 #define FLAT_USER_CS   FLAT_USER_CS64
34 #define FLAT_USER_SS64 FLAT_RING3_SS64
35 #define FLAT_USER_SS32 FLAT_RING3_SS32
36 #define FLAT_USER_SS   FLAT_USER_SS64
37 
38 #define __HYPERVISOR_VIRT_START 0xFFFF800000000000
39 #define __HYPERVISOR_VIRT_END   0xFFFF880000000000
40 #define __MACH2PHYS_VIRT_START  0xFFFF800000000000
41 #define __MACH2PHYS_VIRT_END    0xFFFF804000000000
42 #define __MACH2PHYS_SHIFT       3
43 
44 /*
45  * int HYPERVISOR_set_segment_base(unsigned int which, unsigned long base)
46  *  @which == SEGBASE_*  ;  @base == 64-bit base address
47  * Returns 0 on success.
48  */
49 #define SEGBASE_FS          0
50 #define SEGBASE_GS_USER     1
51 #define SEGBASE_GS_KERNEL   2
52 #define SEGBASE_GS_USER_SEL 3 /* Set user %gs specified in base[15:0] */
53 
54 /*
55  * int HYPERVISOR_iret(void)
56  * All arguments are on the kernel stack, in the following format.
57  * Never returns if successful. Current kernel context is lost.
58  * The saved CS is mapped as follows:
59  *   RING0 -> RING3 kernel mode.
60  *   RING1 -> RING3 kernel mode.
61  *   RING2 -> RING3 kernel mode.
62  *   RING3 -> RING3 user mode.
63  * However RING0 indicates that the guest kernel should return to iteself
64  * directly with
65  *      orb   $3,1*8(%rsp)
66  *      iretq
67  * If flags contains VGCF_in_syscall:
68  *   Restore RAX, RIP, RFLAGS, RSP.
69  *   Discard R11, RCX, CS, SS.
70  * Otherwise:
71  *   Restore RAX, R11, RCX, CS:RIP, RFLAGS, SS:RSP.
72  * All other registers are saved on hypercall entry and restored to user.
73  */
74 /* Guest exited in SYSCALL context? Return to guest with SYSRET? */
75 #define _VGCF_in_syscall 8
76 #define VGCF_in_syscall  (1<<_VGCF_in_syscall)
77 #define VGCF_IN_SYSCALL  VGCF_in_syscall
78 
79 #ifndef __ASSEMBLY__
80 
81 struct iret_context {
82     /* Top of stack (%rsp at point of hypercall). */
83     uint64_t rax, r11, rcx, flags, rip, cs, rflags, rsp, ss;
84     /* Bottom of iret stack frame. */
85 };
86 
87 #if defined(__GNUC__) && !defined(__STRICT_ANSI__)
88 /* Anonymous union includes both 32- and 64-bit names (e.g., eax/rax). */
89 #define __DECL_REG(name) union { \
90     uint64_t r ## name, e ## name; \
91     uint32_t _e ## name; \
92 }
93 #else
94 /* Non-gcc sources must always use the proper 64-bit name (e.g., rax). */
95 #define __DECL_REG(name) uint64_t r ## name
96 #endif
97 
98 struct cpu_user_regs {
99     uint64_t r15;
100     uint64_t r14;
101     uint64_t r13;
102     uint64_t r12;
103     __DECL_REG(bp);
104     __DECL_REG(bx);
105     uint64_t r11;
106     uint64_t r10;
107     uint64_t r9;
108     uint64_t r8;
109     __DECL_REG(ax);
110     __DECL_REG(cx);
111     __DECL_REG(dx);
112     __DECL_REG(si);
113     __DECL_REG(di);
114     uint32_t error_code;    /* private */
115     uint32_t entry_vector;  /* private */
116     __DECL_REG(ip);
117     uint16_t cs, _pad0[1];
118     uint8_t  saved_upcall_mask;
119     uint8_t  _pad1[3];
120     __DECL_REG(flags);      /* rflags.IF == !saved_upcall_mask */
121     __DECL_REG(sp);
122     uint16_t ss, _pad2[3];
123     uint16_t es, _pad3[3];
124     uint16_t ds, _pad4[3];
125     uint16_t fs, _pad5[3]; /* Non-zero => takes precedence over fs_base.     */
126     uint16_t gs, _pad6[3]; /* Non-zero => takes precedence over gs_base_usr. */
127 };
128 DEFINE_GUEST_HANDLE_STRUCT(cpu_user_regs);
129 
130 #undef __DECL_REG
131 
132 #define xen_pfn_to_cr3(pfn) ((unsigned long)(pfn) << 12)
133 #define xen_cr3_to_pfn(cr3) ((unsigned long)(cr3) >> 12)
134 
135 struct arch_vcpu_info {
136     unsigned long cr2;
137     unsigned long pad; /* sizeof(vcpu_info_t) == 64 */
138 };
139 
140 typedef unsigned long xen_callback_t;
141 
142 #define XEN_CALLBACK(__cs, __rip)				\
143 	((unsigned long)(__rip))
144 
145 #endif /* !__ASSEMBLY__ */
146 
147 
148 #endif /* _ASM_X86_XEN_INTERFACE_64_H */
149