1 /******************************************************************************
2  * xen-x86_64.h
3  *
4  * Guest OS interface to x86 64-bit Xen.
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to
8  * deal in the Software without restriction, including without limitation the
9  * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
10  * sell copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
19  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
21  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
22  * DEALINGS IN THE SOFTWARE.
23  *
24  * Copyright (c) 2004-2006, K A Fraser
25  */
26 
27 #ifndef __XEN_PUBLIC_ARCH_X86_XEN_X86_64_H__
28 #define __XEN_PUBLIC_ARCH_X86_XEN_X86_64_H__
29 
30 /*
31  * Hypercall interface:
32  *  Input:  %rdi, %rsi, %rdx, %r10, %r8, %r9 (arguments 1-6)
33  *  Output: %rax
34  * Access is via hypercall page (set up by guest loader or via a Xen MSR):
35  *  call hypercall_page + hypercall-number * 32
36  * Clobbered: argument registers (e.g., 2-arg hypercall clobbers %rdi,%rsi)
37  */
38 
39 /*
40  * 64-bit segment selectors
41  * These flat segments are in the Xen-private section of every GDT. Since these
42  * are also present in the initial GDT, many OSes will be able to avoid
43  * installing their own GDT.
44  */
45 
46 #define FLAT_RING3_CS32 0xe023  /* GDT index 260 */
47 #define FLAT_RING3_CS64 0xe033  /* GDT index 262 */
48 #define FLAT_RING3_DS32 0xe02b  /* GDT index 261 */
49 #define FLAT_RING3_DS64 0x0000  /* NULL selector */
50 #define FLAT_RING3_SS32 0xe02b  /* GDT index 261 */
51 #define FLAT_RING3_SS64 0xe02b  /* GDT index 261 */
52 
53 #define FLAT_KERNEL_DS64 FLAT_RING3_DS64
54 #define FLAT_KERNEL_DS32 FLAT_RING3_DS32
55 #define FLAT_KERNEL_DS   FLAT_KERNEL_DS64
56 #define FLAT_KERNEL_CS64 FLAT_RING3_CS64
57 #define FLAT_KERNEL_CS32 FLAT_RING3_CS32
58 #define FLAT_KERNEL_CS   FLAT_KERNEL_CS64
59 #define FLAT_KERNEL_SS64 FLAT_RING3_SS64
60 #define FLAT_KERNEL_SS32 FLAT_RING3_SS32
61 #define FLAT_KERNEL_SS   FLAT_KERNEL_SS64
62 
63 #define FLAT_USER_DS64 FLAT_RING3_DS64
64 #define FLAT_USER_DS32 FLAT_RING3_DS32
65 #define FLAT_USER_DS   FLAT_USER_DS64
66 #define FLAT_USER_CS64 FLAT_RING3_CS64
67 #define FLAT_USER_CS32 FLAT_RING3_CS32
68 #define FLAT_USER_CS   FLAT_USER_CS64
69 #define FLAT_USER_SS64 FLAT_RING3_SS64
70 #define FLAT_USER_SS32 FLAT_RING3_SS32
71 #define FLAT_USER_SS   FLAT_USER_SS64
72 
73 #define __HYPERVISOR_VIRT_START 0xFFFF800000000000
74 #define __HYPERVISOR_VIRT_END   0xFFFF880000000000
75 #define __MACH2PHYS_VIRT_START  0xFFFF800000000000
76 #define __MACH2PHYS_VIRT_END    0xFFFF804000000000
77 
78 #ifndef HYPERVISOR_VIRT_START
79 #define HYPERVISOR_VIRT_START xen_mk_ulong(__HYPERVISOR_VIRT_START)
80 #define HYPERVISOR_VIRT_END   xen_mk_ulong(__HYPERVISOR_VIRT_END)
81 #endif
82 
83 #define MACH2PHYS_VIRT_START  xen_mk_ulong(__MACH2PHYS_VIRT_START)
84 #define MACH2PHYS_VIRT_END    xen_mk_ulong(__MACH2PHYS_VIRT_END)
85 #define MACH2PHYS_NR_ENTRIES  ((MACH2PHYS_VIRT_END-MACH2PHYS_VIRT_START)>>3)
86 #ifndef machine_to_phys_mapping
87 #define machine_to_phys_mapping ((unsigned long *)HYPERVISOR_VIRT_START)
88 #endif
89 
90 /*
91  * int HYPERVISOR_set_segment_base(unsigned int which, unsigned long base)
92  *  @which == SEGBASE_*  ;  @base == 64-bit base address
93  * Returns 0 on success.
94  */
95 #define SEGBASE_FS          0
96 #define SEGBASE_GS_USER     1
97 #define SEGBASE_GS_KERNEL   2
98 #define SEGBASE_GS_USER_SEL 3 /* Set user %gs specified in base[15:0] */
99 
100 /*
101  * int HYPERVISOR_iret(void)
102  * All arguments are on the kernel stack, in the following format.
103  * Never returns if successful. Current kernel context is lost.
104  * The saved CS is mapped as follows:
105  *   RING0 -> RING3 kernel mode.
106  *   RING1 -> RING3 kernel mode.
107  *   RING2 -> RING3 kernel mode.
108  *   RING3 -> RING3 user mode.
109  * However RING0 indicates that the guest kernel should return to iteself
110  * directly with
111  *      orb   $3,1*8(%rsp)
112  *      iretq
113  * If flags contains VGCF_in_syscall:
114  *   Restore RAX, RIP, RFLAGS, RSP.
115  *   Discard R11, RCX, CS, SS.
116  * Otherwise:
117  *   Restore RAX, R11, RCX, CS:RIP, RFLAGS, SS:RSP.
118  * All other registers are saved on hypercall entry and restored to user.
119  */
120 /* Guest exited in SYSCALL context? Return to guest with SYSRET? */
121 #define _VGCF_in_syscall 8
122 #define VGCF_in_syscall  (1<<_VGCF_in_syscall)
123 #define VGCF_IN_SYSCALL  VGCF_in_syscall
124 
125 #ifndef __ASSEMBLY__
126 
127 struct iret_context {
128     /* Top of stack (%rsp at point of hypercall). */
129     uint64_t rax, r11, rcx, flags, rip, cs, rflags, rsp, ss;
130     /* Bottom of iret stack frame. */
131 };
132 
133 #if defined(__XEN__) || defined(__XEN_TOOLS__)
134 /* Anonymous unions include all permissible names (e.g., al/ah/ax/eax/rax). */
135 #define __DECL_REG_LOHI(which) union { \
136     uint64_t r ## which ## x; \
137     uint32_t e ## which ## x; \
138     uint16_t which ## x; \
139     struct { \
140         uint8_t which ## l; \
141         uint8_t which ## h; \
142     }; \
143 }
144 #define __DECL_REG_LO8(name) union { \
145     uint64_t r ## name; \
146     uint32_t e ## name; \
147     uint16_t name; \
148     uint8_t name ## l; \
149 }
150 #define __DECL_REG_LO16(name) union { \
151     uint64_t r ## name; \
152     uint32_t e ## name; \
153     uint16_t name; \
154 }
155 #define __DECL_REG_HI(num) union { \
156     uint64_t r ## num; \
157     uint32_t r ## num ## d; \
158     uint16_t r ## num ## w; \
159     uint8_t r ## num ## b; \
160 }
161 #elif defined(__GNUC__) && !defined(__STRICT_ANSI__)
162 /* Anonymous union includes both 32- and 64-bit names (e.g., eax/rax). */
163 #define __DECL_REG(name) union { \
164     uint64_t r ## name, e ## name; \
165     uint32_t _e ## name; \
166 }
167 #else
168 /* Non-gcc sources must always use the proper 64-bit name (e.g., rax). */
169 #define __DECL_REG(name) uint64_t r ## name
170 #endif
171 
172 #ifndef __DECL_REG_LOHI
173 #define __DECL_REG_LOHI(name) __DECL_REG(name ## x)
174 #define __DECL_REG_LO8        __DECL_REG
175 #define __DECL_REG_LO16       __DECL_REG
176 #define __DECL_REG_HI(num)    uint64_t r ## num
177 #endif
178 
179 struct cpu_user_regs {
180     __DECL_REG_HI(15);
181     __DECL_REG_HI(14);
182     __DECL_REG_HI(13);
183     __DECL_REG_HI(12);
184     __DECL_REG_LO8(bp);
185     __DECL_REG_LOHI(b);
186     __DECL_REG_HI(11);
187     __DECL_REG_HI(10);
188     __DECL_REG_HI(9);
189     __DECL_REG_HI(8);
190     __DECL_REG_LOHI(a);
191     __DECL_REG_LOHI(c);
192     __DECL_REG_LOHI(d);
193     __DECL_REG_LO8(si);
194     __DECL_REG_LO8(di);
195     uint32_t error_code;    /* private */
196     uint32_t entry_vector;  /* private */
197     __DECL_REG_LO16(ip);
198     uint16_t cs, _pad0[1];
199     uint8_t  saved_upcall_mask;
200     uint8_t  _pad1[3];
201     __DECL_REG_LO16(flags); /* rflags.IF == !saved_upcall_mask */
202     __DECL_REG_LO8(sp);
203     uint16_t ss, _pad2[3];
204     uint16_t es, _pad3[3];
205     uint16_t ds, _pad4[3];
206     uint16_t fs, _pad5[3];
207     uint16_t gs, _pad6[3];
208 };
209 typedef struct cpu_user_regs cpu_user_regs_t;
210 DEFINE_XEN_GUEST_HANDLE(cpu_user_regs_t);
211 
212 #undef __DECL_REG
213 #undef __DECL_REG_LOHI
214 #undef __DECL_REG_LO8
215 #undef __DECL_REG_LO16
216 #undef __DECL_REG_HI
217 
218 #define xen_pfn_to_cr3(pfn) ((unsigned long)(pfn) << 12)
219 #define xen_cr3_to_pfn(cr3) ((unsigned long)(cr3) >> 12)
220 
221 struct arch_vcpu_info {
222     unsigned long cr2;
223     unsigned long pad; /* sizeof(vcpu_info_t) == 64 */
224 };
225 typedef struct arch_vcpu_info arch_vcpu_info_t;
226 
227 typedef unsigned long xen_callback_t;
228 
229 #endif /* !__ASSEMBLY__ */
230 
231 #endif /* __XEN_PUBLIC_ARCH_X86_XEN_X86_64_H__ */
232 
233 /*
234  * Local variables:
235  * mode: C
236  * c-file-style: "BSD"
237  * c-basic-offset: 4
238  * tab-width: 4
239  * indent-tabs-mode: nil
240  * End:
241  */
242