1/* $NetBSD: segments.h,v 1.28 2016/09/02 08:52:12 maxv Exp $ */
2
3/*-
4 * Copyright (c) 1990 The Regents of the University of California.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * William Jolitz.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 *
34 * @(#)segments.h 7.1 (Berkeley) 5/9/91
35 */
36
37/*-
38 * Copyright (c) 1995, 1997
39 * Charles M. Hannum. All rights reserved.
40 * Copyright (c) 1989, 1990 William F. Jolitz
41 *
42 * This code is derived from software contributed to Berkeley by
43 * William Jolitz.
44 *
45 * Redistribution and use in source and binary forms, with or without
46 * modification, are permitted provided that the following conditions
47 * are met:
48 * 1. Redistributions of source code must retain the above copyright
49 * notice, this list of conditions and the following disclaimer.
50 * 2. Redistributions in binary form must reproduce the above copyright
51 * notice, this list of conditions and the following disclaimer in the
52 * documentation and/or other materials provided with the distribution.
53 * 3. All advertising materials mentioning features or use of this software
54 * must display the following acknowledgement:
55 * This product includes software developed by the University of
56 * California, Berkeley and its contributors.
57 * 4. Neither the name of the University nor the names of its contributors
58 * may be used to endorse or promote products derived from this software
59 * without specific prior written permission.
60 *
61 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
62 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
63 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
64 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
65 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
66 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
67 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
68 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
69 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
70 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
71 * SUCH DAMAGE.
72 *
73 * @(#)segments.h 7.1 (Berkeley) 5/9/91
74 */
75
76/*
77 * Adapted for NetBSD/amd64 by fvdl@wasabisystems.com.
78 */
79
80/*
81 * 386 Segmentation Data Structures and definitions
82 * William F. Jolitz (william@ernie.berkeley.edu) 6/20/1989
83 */
84
85#ifndef _AMD64_SEGMENTS_H_
86#define _AMD64_SEGMENTS_H_
87
88#ifdef __x86_64__
89
90#ifdef _KERNEL_OPT
91#include "opt_xen.h"
92#endif
93
94/*
95 * Selectors
96 */
97
98#define ISPL(s) ((s) & SEL_RPL) /* what is the priority level of a selector */
99#ifdef XEN
100#define SEL_KPL 3 /* kernel privilege level */
101#define SEL_XPL 0 /* Xen Hypervisor privilege level */
102#else
103#define SEL_KPL 0 /* kernel privilege level */
104#endif
105#define SEL_UPL 3 /* user privilege level */
106#define SEL_RPL 3 /* requester's privilege level mask */
107#define ISLDT(s) ((s) & SEL_LDT) /* is it local or global */
108#define SEL_LDT 4 /* local descriptor table */
109
110/* Dynamically allocated TSSs and LDTs start (byte offset) */
111#define SYSSEL_START (NGDT_MEM << 3)
112#define DYNSEL_START (SYSSEL_START + (NGDT_SYS << 4))
113
114/*
115 * These define the index not from the start of the GDT, but from
116 * the part of the GDT that they're allocated from.
117 * First NGDT_MEM entries are 8-byte descriptors for CS and DS.
118 * Next NGDT_SYS entries are 16-byte descriptors defining LDTs.
119 *
120 * The rest is 16-byte descriptors for TSS and LDT.
121 */
122
123#define IDXSEL(s) (((s) >> 3) & 0x1fff)
124#define IDXDYNSEL(s) ((((s) & ~SEL_RPL) - DYNSEL_START) >> 4)
125
126#define GSEL(s,r) (((s) << 3) | r)
127#define GSYSSEL(s,r) ((((s) << 4) + SYSSEL_START) | r)
128#define GDYNSEL(s,r) ((((s) << 4) + DYNSEL_START) | r | SEL_KPL)
129
130#define LSEL(s,r) ((s) | r | SEL_LDT)
131
132#define USERMODE(c, f) (ISPL(c) == SEL_UPL)
133#ifdef XEN
134/*
135 * As KPL == UPL, Xen emulate interrupt in kernel context by pushing
136 * a fake CS with XPL privilege
137 */
138#define KERNELMODE(c, f) (ISPL(c) == SEL_XPL)
139#else
140#define KERNELMODE(c, f) (ISPL(c) == SEL_KPL)
141#endif
142
143#ifndef _LOCORE
144
145/*
146 * Memory and System segment descriptors
147 */
148
149/*
150 * System segment descriptor (16 bytes): used for TSS and LDT.
151 */
152struct sys_segment_descriptor {
153 uint64_t sd_lolimit:16; /* segment extent (lsb) */
154 uint64_t sd_lobase:24; /* segment base address (lsb) */
155 uint64_t sd_type:5; /* segment type */
156 uint64_t sd_dpl:2; /* segment descriptor priority level */
157 uint64_t sd_p:1; /* segment descriptor present */
158 uint64_t sd_hilimit:4; /* segment extent (msb) */
159 uint64_t sd_xx1:3; /* avl, long and def32 (not used) */
160 uint64_t sd_gran:1; /* limit granularity (byte/page) */
161 uint64_t sd_hibase:40; /* segment base address (msb) */
162 uint64_t sd_xx2:8; /* reserved */
163 uint64_t sd_zero:5; /* must be zero */
164 uint64_t sd_xx3:19; /* reserved */
165} __packed;
166
167/*
168 * Memory segment descriptor (8 bytes): used for cs, ds, etc.
169 */
170struct mem_segment_descriptor {
171 unsigned sd_lolimit:16; /* segment extent (lsb) */
172 unsigned sd_lobase:24; /* segment base address (lsb) */
173 unsigned sd_type:5; /* segment type */
174 unsigned sd_dpl:2; /* segment descriptor priority level */
175 unsigned sd_p:1; /* segment descriptor present */
176 unsigned sd_hilimit:4; /* segment extent (msb) */
177 unsigned sd_avl:1; /* available */
178 unsigned sd_long:1; /* long mode */
179 unsigned sd_def32:1; /* default 32 vs 16 bit size */
180 unsigned sd_gran:1; /* limit granularity (byte/page) */
181 unsigned sd_hibase:8; /* segment base address (msb) */
182} __packed;
183
184/*
185 * Common part of the above structures. Used to walk descriptor tables.
186 */
187struct common_segment_descriptor {
188 unsigned sdc_lolimit:16;
189 unsigned sdc_lobase:24;
190 unsigned sdc_type:5;
191 unsigned sdc_other:19;
192} __packed;
193
194/*
195 * Gate descriptors (16 bytes).
196 */
197struct gate_descriptor {
198 uint64_t gd_looffset:16;/* gate offset (lsb) */
199 uint64_t gd_selector:16;/* gate segment selector */
200 uint64_t gd_ist:3; /* IST select */
201 uint64_t gd_xx1:5; /* reserved */
202 uint64_t gd_type:5; /* segment type */
203 uint64_t gd_dpl:2; /* segment descriptor priority level */
204 uint64_t gd_p:1; /* segment descriptor present */
205 uint64_t gd_hioffset:48;/* gate offset (msb) */
206 uint64_t gd_xx2:8; /* reserved */
207 uint64_t gd_zero:5; /* must be zero */
208 uint64_t gd_xx3:19; /* reserved */
209} __packed;
210
211/*
212 * Generic descriptor (8 bytes). Note: it does not include system segment
213 * descriptors and gate descriptors, since these are 16-byte-long.
214 */
215union descriptor {
216 struct mem_segment_descriptor sd;
217 uint32_t raw[2];
218 uint64_t raw64;
219} __packed;
220
221/*
222 * Region descriptors, used to load gdt/idt tables before segments yet exist.
223 */
224struct region_descriptor {
225 uint16_t rd_limit; /* segment extent */
226 uint64_t rd_base; /* base address */
227} __packed;
228
229#ifdef _KERNEL
230#ifdef XEN
231extern struct trap_info *idt;
232#else
233extern struct gate_descriptor *idt;
234#endif
235extern char *gdtstore;
236extern char *ldtstore;
237
238void setgate(struct gate_descriptor *, void *, int, int, int, int);
239void unsetgate(struct gate_descriptor *);
240void setregion(struct region_descriptor *, void *, uint16_t);
241void set_sys_segment(struct sys_segment_descriptor *, void *, size_t,
242 int, int, int);
243void set_mem_segment(struct mem_segment_descriptor *, void *, size_t,
244 int, int, int, int, int);
245void cpu_init_idt(void);
246void update_descriptor(void *, void *);
247
248#if !defined(XEN)
249void idt_vec_reserve(int);
250int idt_vec_alloc(int, int);
251void idt_vec_set(int, void (*)(void));
252void idt_vec_free(int);
253#endif
254
255struct lwp;
256void cpu_fsgs_zero(struct lwp *);
257void cpu_fsgs_reload(struct lwp *, int, int);
258
259#endif /* _KERNEL */
260
261#endif /* !_LOCORE */
262
263/* system segments and gate types */
264#define SDT_SYSNULL 0 /* system null */
265#define SDT_SYS286TSS 1 /* system 286 TSS available */
266#define SDT_SYSLDT 2 /* system local descriptor table */
267#define SDT_SYS286BSY 3 /* system 286 TSS busy */
268#define SDT_SYS286CGT 4 /* system 286 call gate */
269#define SDT_SYSTASKGT 5 /* system task gate */
270#define SDT_SYS286IGT 6 /* system 286 interrupt gate */
271#define SDT_SYS286TGT 7 /* system 286 trap gate */
272#define SDT_SYSNULL2 8 /* system null again */
273#define SDT_SYS386TSS 9 /* system 386 TSS available */
274#define SDT_SYSNULL3 10 /* system null again */
275#define SDT_SYS386BSY 11 /* system 386 TSS busy */
276#define SDT_SYS386CGT 12 /* system 386 call gate */
277#define SDT_SYSNULL4 13 /* system null again */
278#define SDT_SYS386IGT 14 /* system 386 interrupt gate */
279#define SDT_SYS386TGT 15 /* system 386 trap gate */
280
281/* memory segment types */
282#define SDT_MEMRO 16 /* memory read only */
283#define SDT_MEMROA 17 /* memory read only accessed */
284#define SDT_MEMRW 18 /* memory read write */
285#define SDT_MEMRWA 19 /* memory read write accessed */
286#define SDT_MEMROD 20 /* memory read only expand dwn limit */
287#define SDT_MEMRODA 21 /* memory read only expand dwn limit accessed */
288#define SDT_MEMRWD 22 /* memory read write expand dwn limit */
289#define SDT_MEMRWDA 23 /* memory read write expand dwn limit accessed */
290#define SDT_MEME 24 /* memory execute only */
291#define SDT_MEMEA 25 /* memory execute only accessed */
292#define SDT_MEMER 26 /* memory execute read */
293#define SDT_MEMERA 27 /* memory execute read accessed */
294#define SDT_MEMEC 28 /* memory execute only conforming */
295#define SDT_MEMEAC 29 /* memory execute only accessed conforming */
296#define SDT_MEMERC 30 /* memory execute read conforming */
297#define SDT_MEMERAC 31 /* memory execute read accessed conforming */
298
299/* is memory segment descriptor pointer ? */
300#define ISMEMSDP(s) ((s->d_type) >= SDT_MEMRO && \
301 (s->d_type) <= SDT_MEMERAC)
302
303/* is 286 gate descriptor pointer ? */
304#define IS286GDP(s) ((s->d_type) >= SDT_SYS286CGT && \
305 (s->d_type) < SDT_SYS286TGT)
306
307/* is 386 gate descriptor pointer ? */
308#define IS386GDP(s) ((s->d_type) >= SDT_SYS386CGT && \
309 (s->d_type) < SDT_SYS386TGT)
310
311/* is gate descriptor pointer ? */
312#define ISGDP(s) (IS286GDP(s) || IS386GDP(s))
313
314/* is segment descriptor pointer ? */
315#define ISSDP(s) (ISMEMSDP(s) || !ISGDP(s))
316
317/* is system segment descriptor pointer ? */
318#define ISSYSSDP(s) (!ISMEMSDP(s) && !ISGDP(s))
319
320/*
321 * Segment Protection Exception code bits
322 */
323#define SEGEX_EXT 0x01 /* recursive or externally induced */
324#define SEGEX_IDT 0x02 /* interrupt descriptor table */
325#define SEGEX_TI 0x04 /* local descriptor table */
326
327/*
328 * Entries in the Interrupt Descriptor Table (IDT)
329 */
330#define NIDT 256
331#define NCPUIDT 32 /* reserved entries for CPU exceptions */
332
333/*
334 * Entries in the Global Descriptor Table (GDT)
335 * The code and data descriptors must come first. There
336 * are NGDT_MEM of them.
337 *
338 * Then come the predefined LDT (and possibly TSS) descriptors.
339 * There are NGDT_SYS of them.
340 */
341#define GNULL_SEL 0 /* Null descriptor */
342#define GCODE_SEL 1 /* Kernel code descriptor */
343#define GDATA_SEL 2 /* Kernel data descriptor */
344#define GUCODE_SEL 3 /* User code descriptor */
345#define GUDATA_SEL 4 /* User data descriptor */
346#define GAPM32CODE_SEL 5
347#define GAPM16CODE_SEL 6
348#define GAPMDATA_SEL 7
349#define GBIOSCODE_SEL 8
350#define GBIOSDATA_SEL 9
351#define GPNPBIOSCODE_SEL 10
352#define GPNPBIOSDATA_SEL 11
353#define GPNPBIOSSCRATCH_SEL 12
354#define GPNPBIOSTRAMP_SEL 13
355#define GUCODE32_SEL 14
356#define GUDATA32_SEL 15
357#define GUFS_SEL 16 /* 32-bit Per-thread %fs */
358#define GUGS_SEL 17 /* 32-bit Per-thread %gs */
359#define NGDT_MEM 18
360
361#define GLDT_SEL 0 /* Default LDT descriptor */
362#define NGDT_SYS 1
363
364#define GDT_ADDR_MEM(s,i) \
365 ((struct mem_segment_descriptor *)((s) + ((i) << 3)))
366#define GDT_ADDR_SYS(s,i) \
367 ((struct sys_segment_descriptor *)((s) + (((i) << 4) + SYSSEL_START)))
368
369/*
370 * Byte offsets in the Local Descriptor Table (LDT)
371 * Strange order because of syscall/sysret insns
372 */
373#define LSYS5CALLS_SEL 0 /* iBCS system call gate */
374/* 8 second half */
375#define LSOL26CALLS_SEL 32 /* Solaris 2.6 system call gate */
376/* 40 second half */
377#define LUCODE32_SEL 48 /* 32 bit user code descriptor */
378#define LUDATA_SEL 56 /* User data descriptor */
379#define LUCODE_SEL 64 /* User code descriptor */
380#define LUDATA32_SEL 72 /* 32 bit user data descriptor (needed?)*/
381#define LBSDICALLS_SEL 128 /* BSDI system call gate */
382/* 136 second half */
383
384#define LDT_SIZE 144
385
386#define LSYSRETBASE_SEL LUCODE32_SEL
387
388/*
389 * Checks for valid user selectors. If USER_LDT ever gets implemented
390 * for amd64, these must check the ldt length and SEL_UPL if a user
391 * ldt is active.
392 */
393#define VALID_USER_DSEL32(s) \
394 (((s) & 0xffff) == GSEL(GUDATA32_SEL, SEL_UPL) || \
395 ((s) & 0xffff) == LSEL(LUDATA32_SEL, SEL_UPL))
396#define VALID_USER_CSEL32(s) \
397 ((s) == GSEL(GUCODE32_SEL, SEL_UPL) || (s) == LSEL(LUCODE32_SEL, SEL_UPL))
398#define VALID_USER_FSEL32(s) \
399 (((s) & 0xffff) == GSEL(GUFS_SEL, SEL_UPL))
400#define VALID_USER_GSEL32(s) \
401 (((s) & 0xffff) == GSEL(GUGS_SEL, SEL_UPL))
402
403#define VALID_USER_CSEL(s) \
404 ((s) == GSEL(GUCODE_SEL, SEL_UPL) || (s) == LSEL(LUCODE_SEL, SEL_UPL))
405#define VALID_USER_DSEL(s) \
406 ((s) == GSEL(GUDATA_SEL, SEL_UPL) || (s) == LSEL(LUDATA_SEL, SEL_UPL))
407
408#else /* __x86_64__ */
409
410#include <i386/segments.h>
411
412#endif /* __x86_64__ */
413
414#endif /* _AMD64_SEGMENTS_H_ */
415