/* $NetBSD: segments.h,v 1.38 2021/04/17 20:12:55 rillig Exp $ */ /* * Copyright (c) 1990 The Regents of the University of California. * All rights reserved. * * This code is derived from software contributed to Berkeley by * William Jolitz. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)segments.h 7.1 (Berkeley) 5/9/91 */ /* * Copyright (c) 1995, 1997 * Charles M. Hannum. All rights reserved. * Copyright (c) 1989, 1990 William F. Jolitz * * This code is derived from software contributed to Berkeley by * William Jolitz. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)segments.h 7.1 (Berkeley) 5/9/91 */ /* * Adapted for NetBSD/amd64 by fvdl@wasabisystems.com. */ /* * 386 Segmentation Data Structures and definitions * William F. Jolitz (william@ernie.berkeley.edu) 6/20/1989 */ #ifndef _AMD64_SEGMENTS_H_ #define _AMD64_SEGMENTS_H_ #ifdef __x86_64__ #ifdef _KERNEL_OPT #include "opt_xen.h" #endif /* * Selectors */ #define ISPL(s) ((s) & SEL_RPL) /* what is the priority level of a selector */ #ifdef XENPV #define SEL_KPL 3 /* kernel privilege level */ #define SEL_XPL 0 /* Xen Hypervisor privilege level */ #else #define SEL_KPL 0 /* kernel privilege level */ #endif #define SEL_UPL 3 /* user privilege level */ #define SEL_RPL 3 /* requester's privilege level mask */ #define ISLDT(s) ((s) & SEL_LDT) /* is it local or global */ #define SEL_LDT 4 /* local descriptor table */ #ifdef XENPV #define IOPL_KPL 1 #else #define IOPL_KPL SEL_KPL #endif /* Dynamically allocated TSSs and LDTs start (byte offset) */ #define SYSSEL_START (NGDT_MEM << 3) #define DYNSEL_START (SYSSEL_START + (NGDT_SYS << 4)) /* * These define the index not from the start of the GDT, but from * the part of the GDT that they're allocated from. * First NGDT_MEM entries are 8-byte descriptors for CS and DS. * Next NGDT_SYS entries are 16-byte descriptors defining LDTs. * * The rest is 16-byte descriptors for TSS and LDT. */ #define IDXSEL(s) (((s) >> 3) & 0x1fff) #define IDXDYNSEL(s) ((((s) & ~SEL_RPL) - DYNSEL_START) >> 4) #define GSEL(s,r) (((s) << 3) | r) #define GSYSSEL(s,r) ((((s) << 4) + SYSSEL_START) | r) #define GDYNSEL(s,r) ((((s) << 4) + DYNSEL_START) | r | SEL_KPL) #define LSEL(s,r) ((s) | r | SEL_LDT) #define USERMODE(c) (ISPL(c) == SEL_UPL) #ifdef XENPV /* * As KPL == UPL, Xen emulate interrupt in kernel context by pushing * a fake CS with XPL privilege */ #define KERNELMODE(c) (ISPL(c) == SEL_XPL) #else #define KERNELMODE(c) (ISPL(c) == SEL_KPL) #endif #ifndef _LOCORE /* * Memory and System segment descriptors */ /* * System segment descriptor (16 bytes): used for TSS and LDT. */ struct sys_segment_descriptor { uint64_t sd_lolimit:16; /* segment extent (lsb) */ uint64_t sd_lobase:24; /* segment base address (lsb) */ uint64_t sd_type:5; /* segment type */ uint64_t sd_dpl:2; /* segment descriptor priority level */ uint64_t sd_p:1; /* segment descriptor present */ uint64_t sd_hilimit:4; /* segment extent (msb) */ uint64_t sd_xx1:3; /* avl, long and def32 (not used) */ uint64_t sd_gran:1; /* limit granularity (byte/page) */ uint64_t sd_hibase:40; /* segment base address (msb) */ uint64_t sd_xx2:8; /* reserved */ uint64_t sd_zero:5; /* must be zero */ uint64_t sd_xx3:19; /* reserved */ } __packed; /* * Memory segment descriptor (8 bytes): used for cs, ds, etc. */ struct mem_segment_descriptor { unsigned sd_lolimit:16; /* segment extent (lsb) */ unsigned sd_lobase:24; /* segment base address (lsb) */ unsigned sd_type:5; /* segment type */ unsigned sd_dpl:2; /* segment descriptor priority level */ unsigned sd_p:1; /* segment descriptor present */ unsigned sd_hilimit:4; /* segment extent (msb) */ unsigned sd_avl:1; /* available */ unsigned sd_long:1; /* long mode */ unsigned sd_def32:1; /* default 32 vs 16 bit size */ unsigned sd_gran:1; /* limit granularity (byte/page) */ unsigned sd_hibase:8; /* segment base address (msb) */ } __packed; /* * Common part of the above structures. Used to walk descriptor tables. */ struct common_segment_descriptor { unsigned sdc_lolimit:16; unsigned sdc_lobase:24; unsigned sdc_type:5; unsigned sdc_other:19; } __packed; /* * Gate descriptors (16 bytes). */ struct gate_descriptor { uint64_t gd_looffset:16;/* gate offset (lsb) */ uint64_t gd_selector:16;/* gate segment selector */ uint64_t gd_ist:3; /* IST select */ uint64_t gd_xx1:5; /* reserved */ uint64_t gd_type:5; /* segment type */ uint64_t gd_dpl:2; /* segment descriptor priority level */ uint64_t gd_p:1; /* segment descriptor present */ uint64_t gd_hioffset:48;/* gate offset (msb) */ uint64_t gd_xx2:8; /* reserved */ uint64_t gd_zero:5; /* must be zero */ uint64_t gd_xx3:19; /* reserved */ } __packed; /* * Generic descriptor (8 bytes). Note: it does not include system segment * descriptors and gate descriptors, since these are 16-byte-long. */ union descriptor { struct mem_segment_descriptor sd; uint32_t raw[2]; uint64_t raw64; } __packed; /* * Region descriptors, used to load gdt/idt tables before segments yet exist. */ struct region_descriptor { uint16_t rd_limit; /* segment extent */ uint64_t rd_base; /* base address */ } __packed; #ifdef _KERNEL #ifdef XENPV typedef struct trap_info idt_descriptor_t; #else typedef struct gate_descriptor idt_descriptor_t; #endif /* XENPV */ extern char *gdtstore; extern char *ldtstore; void setgate(struct gate_descriptor *, void *, int, int, int, int); void unsetgate(struct gate_descriptor *); void set_idtgate(idt_descriptor_t *, void *, int, int, int, int); void unset_idtgate(idt_descriptor_t *); void setregion(struct region_descriptor *, void *, uint16_t); void set_sys_segment(struct sys_segment_descriptor *, void *, size_t, int, int, int); void set_mem_segment(struct mem_segment_descriptor *, void *, size_t, int, int, int, int, int); void update_descriptor(void *, void *); struct idt_vec; void idt_vec_reserve(struct idt_vec *, int); int idt_vec_alloc(struct idt_vec *, int, int); void idt_vec_set(struct idt_vec *, int, void (*)(void)); void idt_vec_free(struct idt_vec *, int); void idt_vec_init_cpu_md(struct idt_vec *, cpuid_t); bool idt_vec_is_pcpu(void); struct idt_vec * idt_vec_ref(struct idt_vec *); struct lwp; void cpu_segregs64_zero(struct lwp *); void cpu_segregs32_zero(struct lwp *); void cpu_fsgs_reload(struct lwp *, int, int); #endif /* _KERNEL */ #endif /* !_LOCORE */ /* system segments and gate types */ #define SDT_SYSNULL 0 /* system null */ #define SDT_SYS286TSS 1 /* system 286 TSS available */ #define SDT_SYSLDT 2 /* system local descriptor table */ #define SDT_SYS286BSY 3 /* system 286 TSS busy */ #define SDT_SYS286CGT 4 /* system 286 call gate */ #define SDT_SYSTASKGT 5 /* system task gate */ #define SDT_SYS286IGT 6 /* system 286 interrupt gate */ #define SDT_SYS286TGT 7 /* system 286 trap gate */ #define SDT_SYSNULL2 8 /* system null again */ #define SDT_SYS386TSS 9 /* system 386 TSS available */ #define SDT_SYSNULL3 10 /* system null again */ #define SDT_SYS386BSY 11 /* system 386 TSS busy */ #define SDT_SYS386CGT 12 /* system 386 call gate */ #define SDT_SYSNULL4 13 /* system null again */ #define SDT_SYS386IGT 14 /* system 386 interrupt gate */ #define SDT_SYS386TGT 15 /* system 386 trap gate */ /* memory segment types */ #define SDT_MEMRO 16 /* memory read only */ #define SDT_MEMROA 17 /* memory read only accessed */ #define SDT_MEMRW 18 /* memory read write */ #define SDT_MEMRWA 19 /* memory read write accessed */ #define SDT_MEMROD 20 /* memory read only expand dwn limit */ #define SDT_MEMRODA 21 /* memory read only expand dwn limit accessed */ #define SDT_MEMRWD 22 /* memory read write expand dwn limit */ #define SDT_MEMRWDA 23 /* memory read write expand dwn limit accessed */ #define SDT_MEME 24 /* memory execute only */ #define SDT_MEMEA 25 /* memory execute only accessed */ #define SDT_MEMER 26 /* memory execute read */ #define SDT_MEMERA 27 /* memory execute read accessed */ #define SDT_MEMEC 28 /* memory execute only conforming */ #define SDT_MEMEAC 29 /* memory execute only accessed conforming */ #define SDT_MEMERC 30 /* memory execute read conforming */ #define SDT_MEMERAC 31 /* memory execute read accessed conforming */ /* * Segment Protection Exception code bits */ #define SEGEX_EXT 0x01 /* recursive or externally induced */ #define SEGEX_IDT 0x02 /* interrupt descriptor table */ #define SEGEX_TI 0x04 /* local descriptor table */ /* * Entries in the Interrupt Descriptor Table (IDT) */ #define NIDT 256 #define NCPUIDT 32 /* reserved entries for CPU exceptions */ /* * Entries in the Global Descriptor Table (GDT) * The code and data descriptors must come first. There * are NGDT_MEM of them. * * Then come the predefined LDT (and possibly TSS) descriptors. * There are NGDT_SYS of them. */ #define GNULL_SEL 0 /* Null descriptor */ #define GCODE_SEL 1 /* Kernel code descriptor */ #define GDATA_SEL 2 /* Kernel data descriptor */ #define GUCODE_SEL 3 /* User code descriptor */ #define GUDATA_SEL 4 /* User data descriptor */ #define GAPM32CODE_SEL 5 #define GAPM16CODE_SEL 6 #define GAPMDATA_SEL 7 #define GBIOSCODE_SEL 8 #define GBIOSDATA_SEL 9 #define GPNPBIOSCODE_SEL 10 #define GPNPBIOSDATA_SEL 11 #define GPNPBIOSSCRATCH_SEL 12 #define GPNPBIOSTRAMP_SEL 13 #define GUCODE32_SEL 14 #define GUDATA32_SEL 15 #define GUFS_SEL 16 /* 32-bit Per-thread %fs */ #define GUGS_SEL 17 /* 32-bit Per-thread %gs */ #define NGDT_MEM 18 #define GLDT_SEL 0 /* Default LDT descriptor */ #define NGDT_SYS 1 #define GDT_ADDR_MEM(s,i) \ ((struct mem_segment_descriptor *)((s) + ((i) << 3))) #define GDT_ADDR_SYS(s,i) \ ((struct sys_segment_descriptor *)((s) + (((i) << 4) + SYSSEL_START))) /* * Byte offsets in the Local Descriptor Table (LDT) * Strange order because of syscall/sysret insns */ #define LUCODE32_SEL 48 /* 32 bit user code descriptor */ #define LUDATA_SEL 56 /* User data descriptor */ #define LUCODE_SEL 64 /* User code descriptor */ #define LUDATA32_SEL 72 /* 32 bit user data descriptor (needed?)*/ #define LDT_SIZE 80 #define LSYSRETBASE_SEL LUCODE32_SEL /* * Checks for valid user selectors. */ #define VALID_USER_DSEL32(s) \ (((s) & 0xffff) == GSEL(GUDATA32_SEL, SEL_UPL) || \ ((s) & 0xffff) == LSEL(LUDATA32_SEL, SEL_UPL)) #define VALID_USER_CSEL32(s) \ ((s) == GSEL(GUCODE32_SEL, SEL_UPL) || (s) == LSEL(LUCODE32_SEL, SEL_UPL)) #define VALID_USER_FSEL32(s) \ (((s) & 0xffff) == GSEL(GUFS_SEL, SEL_UPL)) #define VALID_USER_GSEL32(s) \ (((s) & 0xffff) == GSEL(GUGS_SEL, SEL_UPL)) #define VALID_USER_CSEL(s) \ ((s) == GSEL(GUCODE_SEL, SEL_UPL) || (s) == LSEL(LUCODE_SEL, SEL_UPL)) #define VALID_USER_DSEL(s) \ ((s) == GSEL(GUDATA_SEL, SEL_UPL) || (s) == LSEL(LUDATA_SEL, SEL_UPL)) #else /* __x86_64__ */ #include <i386/segments.h> #endif /* __x86_64__ */ #endif /* _AMD64_SEGMENTS_H_ */
