xref: /netbsd-src/sys/arch/amd64/include/segments.h (revision 1ffa7b76c40339c17a0fb2a09fac93f287cfc046)
1 /*	$NetBSD: segments.h,v 1.1 2003/04/26 18:39:47 fvdl Exp $	*/
2 
3 /*-
4  * Copyright (c) 1995, 1997
5  *	Charles M. Hannum.  All rights reserved.
6  * Copyright (c) 1989, 1990 William F. Jolitz
7  * Copyright (c) 1990 The Regents of the University of California.
8  * All rights reserved.
9  *
10  * This code is derived from software contributed to Berkeley by
11  * William Jolitz.
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  * 1. Redistributions of source code must retain the above copyright
17  *    notice, this list of conditions and the following disclaimer.
18  * 2. Redistributions in binary form must reproduce the above copyright
19  *    notice, this list of conditions and the following disclaimer in the
20  *    documentation and/or other materials provided with the distribution.
21  * 3. All advertising materials mentioning features or use of this software
22  *    must display the following acknowledgement:
23  *	This product includes software developed by the University of
24  *	California, Berkeley and its contributors.
25  * 4. Neither the name of the University nor the names of its contributors
26  *    may be used to endorse or promote products derived from this software
27  *    without specific prior written permission.
28  *
29  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
30  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
31  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
32  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
33  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
34  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
35  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
36  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
37  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
38  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
39  * SUCH DAMAGE.
40  *
41  *	@(#)segments.h	7.1 (Berkeley) 5/9/91
42  */
43 
44 /*
45  * Adapted for NetBSD/amd64 by fvdl@wasabisystems.com.
46  */
47 
48 /*
49  * 386 Segmentation Data Structures and definitions
50  *	William F. Jolitz (william@ernie.berkeley.edu) 6/20/1989
51  */
52 
53 #ifndef _AMD64_SEGMENTS_H_
54 #define _AMD64_SEGMENTS_H_
55 
56 /*
57  * Selectors
58  */
59 
60 #define	ISPL(s)		((s) & SEL_RPL)	/* what is the priority level of a selector */
61 #define	SEL_KPL		0		/* kernel privilege level */
62 #define	SEL_UPL		3		/* user privilege level */
63 #define	SEL_RPL		3		/* requester's privilege level mask */
64 #define	ISLDT(s)	((s) & SEL_LDT)	/* is it local or global */
65 #define	SEL_LDT		4		/* local descriptor table */
66 
67 /* Dynamically allocated TSSs and LDTs start (byte offset) */
68 #define SYSSEL_START	(NGDT_MEM << 3)
69 #define DYNSEL_START	(SYSSEL_START + (NGDT_SYS << 4))
70 
71 /*
72  * These define the index not from the start of the GDT, but from
73  * the part of the GDT that they're allocated from.
74  * First NGDT_MEM entries are 8-byte descriptors for CS and DS.
75  * Next NGDT_SYS entries are 16-byte descriptors defining LDTs.
76  *
77  * The rest is 16-byte descriptors for TSS and LDT.
78  */
79 
80 #define	IDXSEL(s)	(((s) >> 3) & 0x1fff)
81 #define IDXDYNSEL(s)	((((s) & ~SEL_RPL) - DYNSEL_START) >> 4)
82 
83 #define	GSEL(s,r)	(((s) << 3) | r)
84 #define	GSYSSEL(s,r)	((((s) << 4) + SYSSEL_START) | r)
85 #define GDYNSEL(s,r)	((((s) << 4) + DYNSEL_START) | r | SEL_KPL)
86 
87 #define LSEL(s,r)	((s) | r | SEL_LDT)
88 
89 #define	USERMODE(c, f)		(ISPL(c) == SEL_UPL)
90 #define	KERNELMODE(c, f)	(ISPL(c) == SEL_KPL)
91 
92 #ifndef _LOCORE
93 
94 /*
95  * Memory and System segment descriptors
96  */
97 
98 /*
99  * Below is used for TSS and LDT.
100  */
101 struct sys_segment_descriptor {
102 /*BITFIELDTYPE*/ u_int64_t sd_lolimit:16;/* segment extent (lsb) */
103 /*BITFIELDTYPE*/ u_int64_t sd_lobase:24;/* segment base address (lsb) */
104 /*BITFIELDTYPE*/ u_int64_t sd_type:5;	/* segment type */
105 /*BITFIELDTYPE*/ u_int64_t sd_dpl:2;	/* segment descriptor priority level */
106 /*BITFIELDTYPE*/ u_int64_t sd_p:1;	/* segment descriptor present */
107 /*BITFIELDTYPE*/ u_int64_t sd_hilimit:4;/* segment extent (msb) */
108 /*BITFIELDTYPE*/ u_int64_t sd_xx1:3;	/* avl, long and def32 (not used) */
109 /*BITFIELDTYPE*/ u_int64_t sd_gran:1;	/* limit granularity (byte/page) */
110 /*BITFIELDTYPE*/ u_int64_t sd_hibase:40;/* segment base address (msb) */
111 /*BITFIELDTYPE*/ u_int64_t sd_xx2:8;	/* reserved */
112 /*BITFIELDTYPE*/ u_int64_t sd_zero:5;	/* must be zero */
113 /*BITFIELDTYPE*/ u_int64_t sd_xx3:19;	/* reserved */
114 } __attribute__((packed));
115 
116 /*
117  * Below is used for cs, ds, etc.
118  */
119 struct mem_segment_descriptor {
120 	unsigned sd_lolimit:16;         /* segment extent (lsb) */
121 	unsigned sd_lobase:24;          /* segment base address (lsb) */
122 	unsigned sd_type:5;             /* segment type */
123 	unsigned sd_dpl:2;              /* segment descriptor priority level */
124 	unsigned sd_p:1;                /* segment descriptor present */
125 	unsigned sd_hilimit:4;          /* segment extent (msb) */
126 	unsigned sd_avl:1;		/* available */
127 	unsigned sd_long:1;		/* long mode */
128 	unsigned sd_def32:1;            /* default 32 vs 16 bit size */
129 	unsigned sd_gran:1;             /* limit granularity (byte/page) */
130 	unsigned sd_hibase:8;           /* segment base address (msb) */
131 } __attribute__((packed));
132 
133 /*
134  * Gate descriptors (e.g. indirect descriptors)
135  */
136 struct gate_descriptor {
137 /*BITFIELDTYPE*/ u_int64_t gd_looffset:16;/* gate offset (lsb) */
138 /*BITFIELDTYPE*/ u_int64_t gd_selector:16;/* gate segment selector */
139 /*BITFIELDTYPE*/ u_int64_t gd_ist:3;	/* IST select */
140 /*BITFIELDTYPE*/ u_int64_t gd_xx1:5;	/* reserved */
141 /*BITFIELDTYPE*/ u_int64_t gd_type:5;	/* segment type */
142 /*BITFIELDTYPE*/ u_int64_t gd_dpl:2;	/* segment descriptor priority level */
143 /*BITFIELDTYPE*/ u_int64_t gd_p:1;	/* segment descriptor present */
144 /*BITFIELDTYPE*/ u_int64_t gd_hioffset:48;/* gate offset (msb) */
145 /*BITFIELDTYPE*/ u_int64_t gd_xx2:8;	/* reserved */
146 /*BITFIELDTYPE*/ u_int64_t gd_zero:5;	/* must be zero */
147 /*BITFIELDTYPE*/ u_int64_t gd_xx3:19;	/* reserved */
148 } __attribute__((packed));
149 
150 /*
151  * region descriptors, used to load gdt/idt tables before segments yet exist.
152  */
153 struct region_descriptor {
154 	u_int16_t rd_limit;		/* segment extent */
155 	u_int64_t rd_base;		/* base address  */
156 } __attribute__((packed));
157 
158 #ifdef _KERNEL
159 #if 0
160 extern struct sys_segment_descriptor *ldt;
161 #endif
162 extern struct gate_descriptor *idt;
163 extern char *gdtstore;
164 extern char *ldtstore;
165 
166 void setgate __P((struct gate_descriptor *, void *, int, int, int, int));
167 void unsetgate __P((struct gate_descriptor *));
168 void setregion __P((struct region_descriptor *, void *, u_int16_t));
169 void set_sys_segment __P((struct sys_segment_descriptor *, void *, size_t,
170 			  int, int, int));
171 void set_mem_segment __P((struct mem_segment_descriptor *, void *, size_t,
172 			  int, int, int, int, int));
173 int idt_vec_alloc __P((int, int));
174 void idt_vec_set __P((int, void (*)(void)));
175 void idt_vec_free __P((int));
176 void cpu_init_idt __P((void));
177 
178 #endif /* _KERNEL */
179 
180 #endif /* !_LOCORE */
181 
182 /* system segments and gate types */
183 #define	SDT_SYSNULL	 0	/* system null */
184 #define	SDT_SYS286TSS	 1	/* system 286 TSS available */
185 #define	SDT_SYSLDT	 2	/* system local descriptor table */
186 #define	SDT_SYS286BSY	 3	/* system 286 TSS busy */
187 #define	SDT_SYS286CGT	 4	/* system 286 call gate */
188 #define	SDT_SYSTASKGT	 5	/* system task gate */
189 #define	SDT_SYS286IGT	 6	/* system 286 interrupt gate */
190 #define	SDT_SYS286TGT	 7	/* system 286 trap gate */
191 #define	SDT_SYSNULL2	 8	/* system null again */
192 #define	SDT_SYS386TSS	 9	/* system 386 TSS available */
193 #define	SDT_SYSNULL3	10	/* system null again */
194 #define	SDT_SYS386BSY	11	/* system 386 TSS busy */
195 #define	SDT_SYS386CGT	12	/* system 386 call gate */
196 #define	SDT_SYSNULL4	13	/* system null again */
197 #define	SDT_SYS386IGT	14	/* system 386 interrupt gate */
198 #define	SDT_SYS386TGT	15	/* system 386 trap gate */
199 
200 /* memory segment types */
201 #define	SDT_MEMRO	16	/* memory read only */
202 #define	SDT_MEMROA	17	/* memory read only accessed */
203 #define	SDT_MEMRW	18	/* memory read write */
204 #define	SDT_MEMRWA	19	/* memory read write accessed */
205 #define	SDT_MEMROD	20	/* memory read only expand dwn limit */
206 #define	SDT_MEMRODA	21	/* memory read only expand dwn limit accessed */
207 #define	SDT_MEMRWD	22	/* memory read write expand dwn limit */
208 #define	SDT_MEMRWDA	23	/* memory read write expand dwn limit acessed */
209 #define	SDT_MEME	24	/* memory execute only */
210 #define	SDT_MEMEA	25	/* memory execute only accessed */
211 #define	SDT_MEMER	26	/* memory execute read */
212 #define	SDT_MEMERA	27	/* memory execute read accessed */
213 #define	SDT_MEMEC	28	/* memory execute only conforming */
214 #define	SDT_MEMEAC	29	/* memory execute only accessed conforming */
215 #define	SDT_MEMERC	30	/* memory execute read conforming */
216 #define	SDT_MEMERAC	31	/* memory execute read accessed conforming */
217 
218 /* is memory segment descriptor pointer ? */
219 #define ISMEMSDP(s)	((s->d_type) >= SDT_MEMRO && \
220 			 (s->d_type) <= SDT_MEMERAC)
221 
222 /* is 286 gate descriptor pointer ? */
223 #define IS286GDP(s)	((s->d_type) >= SDT_SYS286CGT && \
224 			 (s->d_type) < SDT_SYS286TGT)
225 
226 /* is 386 gate descriptor pointer ? */
227 #define IS386GDP(s)	((s->d_type) >= SDT_SYS386CGT && \
228 			 (s->d_type) < SDT_SYS386TGT)
229 
230 /* is gate descriptor pointer ? */
231 #define ISGDP(s)	(IS286GDP(s) || IS386GDP(s))
232 
233 /* is segment descriptor pointer ? */
234 #define ISSDP(s)	(ISMEMSDP(s) || !ISGDP(s))
235 
236 /* is system segment descriptor pointer ? */
237 #define ISSYSSDP(s)	(!ISMEMSDP(s) && !ISGDP(s))
238 
239 /*
240  * Segment Protection Exception code bits
241  */
242 #define	SEGEX_EXT	0x01	/* recursive or externally induced */
243 #define	SEGEX_IDT	0x02	/* interrupt descriptor table */
244 #define	SEGEX_TI	0x04	/* local descriptor table */
245 
246 /*
247  * Entries in the Interrupt Descriptor Table (IDT)
248  */
249 #define	NIDT	256
250 #define	NRSVIDT	32		/* reserved entries for cpu exceptions */
251 
252 /*
253  * Entries in the Global Descriptor Table (GDT)
254  * The code and data descriptors must come first. There
255  * are NGDT_MEM of them.
256  *
257  * Then come the predefined LDT (and possibly TSS) descriptors.
258  * There are NGDT_SYS of them.
259  */
260 #define	GNULL_SEL	0	/* Null descriptor */
261 #define	GCODE_SEL	1	/* Kernel code descriptor */
262 #define	GDATA_SEL	2	/* Kernel data descriptor */
263 #define	GUCODE_SEL	3	/* User code descriptor */
264 #define	GUDATA_SEL	4	/* User data descriptor */
265 #define	GAPM32CODE_SEL	5
266 #define	GAPM16CODE_SEL	6
267 #define	GAPMDATA_SEL	7
268 #define	GBIOSCODE_SEL	8
269 #define	GBIOSDATA_SEL	9
270 #define GPNPBIOSCODE_SEL 10
271 #define GPNPBIOSDATA_SEL 11
272 #define GPNPBIOSSCRATCH_SEL 12
273 #define GPNPBIOSTRAMP_SEL 13
274 #define GUCODE32_SEL	14
275 #define GUDATA32_SEL	15
276 #define NGDT_MEM 16
277 
278 #define	GLDT_SEL	0	/* Default LDT descriptor */
279 #define NGDT_SYS	1
280 
281 #define GDT_SYS_OFFSET	(NGDT_MEM << 3)
282 
283 #define GDT_ADDR_MEM(s,i)	\
284     ((struct mem_segment_descriptor *)((s) + ((i) << 3)))
285 #define GDT_ADDR_SYS(s,i)	\
286    ((struct sys_segment_descriptor *)((s) + (((i) << 4) + SYSSEL_START)))
287 
288 /*
289  * Byte offsets in the Local Descriptor Table (LDT)
290  * Strange order because of syscall/sysret insns
291  */
292 #define	LSYS5CALLS_SEL	0	/* iBCS system call gate */
293 #define LUCODE32_SEL	8	/* 32 bit user code descriptor */
294 #define	LUDATA_SEL	16	/* User data descriptor */
295 #define	LUCODE_SEL	24	/* User code descriptor */
296 #define	LSOL26CALLS_SEL	32	/* Solaris 2.6 system call gate */
297 #define LUDATA32_SEL	56	/* 32 bit user data descriptor (needed?)*/
298 #define	LBSDICALLS_SEL	128	/* BSDI system call gate */
299 
300 #define LDT_SIZE	144
301 
302 #define LSYSRETBASE_SEL	LUCODE32_SEL
303 
304 #endif /* _AMD64_SEGMENTS_H_ */
305