/* $NetBSD: segments.h,v 1.70 2022/05/18 13:56:32 andvar 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 */ /* * 386 Segmentation Data Structures and definitions * William F. Jolitz (william@ernie.berkeley.edu) 6/20/1989 */ #ifndef _I386_SEGMENTS_H_ #define _I386_SEGMENTS_H_ #ifdef _KERNEL_OPT #include "opt_xen.h" #endif /* * Selectors */ #define ISPL(s) ((s) & SEL_RPL) /* what is the priority level of a selector */ #ifndef XENPV #define SEL_KPL 0 /* kernel privilege level */ #else #define SEL_XEN 0 /* Xen privilege level */ #define SEL_KPL 1 /* kernel privilege level */ #endif /* XENPV */ #define SEL_UPL 3 /* user privilege level */ #define SEL_RPL 3 /* requester's privilege level mask */ #ifdef XENPV #define CHK_UPL 2 /* user privilege level mask */ #else #define CHK_UPL SEL_RPL #endif /* XENPV */ #define ISLDT(s) ((s) & SEL_LDT) /* is it local or global */ #define SEL_LDT 4 /* local descriptor table */ #define IOPL_KPL SEL_KPL /* Dynamically allocated TSSs and LDTs start (byte offset) */ #define DYNSEL_START (NGDT << 3) #define IDXSEL(s) (((s) >> 3) & 0x1fff) /* index of selector */ #define IDXSELN(s) (((s) >> 3)) /* index of selector */ #define IDXDYNSEL(s) ((((s) & ~SEL_RPL) - DYNSEL_START) >> 3) #define GSEL(s,r) (((s) << 3) | r) /* a global selector */ #define GSYSSEL(s,r) GSEL(s,r) /* compat with amd64 */ #define GDYNSEL(s,r) ((((s) << 3) + DYNSEL_START) | r | SEL_KPL) #define LSEL(s,r) (((s) << 3) | r | SEL_LDT) /* a local selector */ #define USERMODE(c) (ISPL(c) == SEL_UPL) #define KERNELMODE(c) (ISPL(c) == SEL_KPL) #ifndef _LOCORE #if __GNUC__ == 2 && __GNUC_MINOR__ < 7 #pragma pack(1) #endif /* * Memory and System segment descriptors (both 8 bytes). */ struct 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_xx:2; /* unused */ 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; /* * Gate descriptors (8 bytes). */ struct gate_descriptor { unsigned gd_looffset:16; /* gate offset (lsb) */ unsigned gd_selector:16; /* gate segment selector */ unsigned gd_stkcpy:5; /* number of stack wds to cpy */ unsigned gd_xx:3; /* unused */ unsigned gd_type:5; /* segment type */ unsigned gd_dpl:2; /* segment descriptor priority level */ unsigned gd_p:1; /* segment descriptor present */ unsigned gd_hioffset:16; /* gate offset (msb) */ } __packed; /* * Xen-specific? */ struct ldt_descriptor { __vaddr_t ld_base; uint32_t ld_entries; } __packed; /* * Generic descriptor (8 bytes). */ union descriptor { struct segment_descriptor sd; struct gate_descriptor gd; struct ldt_descriptor ld; uint32_t raw[2]; uint64_t raw64; } __packed; /* * Region descriptors, used to load gdt/idt tables before segments yet exist. */ struct region_descriptor { unsigned rd_limit:16; /* segment extent */ unsigned rd_base:32; /* base address */ } __packed; #if __GNUC__ == 2 && __GNUC_MINOR__ < 7 #pragma pack(4) #endif #ifdef _KERNEL #ifdef XENPV typedef struct trap_info idt_descriptor_t; #else typedef struct gate_descriptor idt_descriptor_t; #endif /* XENPV */ extern union descriptor *gdtstore, *ldtstore; void setgate(struct gate_descriptor *, void *, int, int, int, int); void set_idtgate(idt_descriptor_t *, void *, int, int, int, int); void unset_idtgate(idt_descriptor_t *); void setregion(struct region_descriptor *, void *, size_t); void setsegment(struct segment_descriptor *, const void *, size_t, int, int, int, int); void unsetgate(struct gate_descriptor *); void update_descriptor(union descriptor *, union descriptor *); 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 *); #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 */ #define SDTYPE(p) (((const struct segment_descriptor *)(p))->sd_type) /* is memory segment descriptor pointer ? */ #define ISMEMSDP(s) (SDTYPE(s) >= SDT_MEMRO && \ SDTYPE(s) <= SDT_MEMERAC) /* is 286 gate descriptor pointer ? */ #define IS286GDP(s) (SDTYPE(s) >= SDT_SYS286CGT && \ SDTYPE(s) < SDT_SYS286TGT) /* is 386 gate descriptor pointer ? */ #define IS386GDP(s) (SDTYPE(s) >= SDT_SYS386CGT && \ SDTYPE(s) < SDT_SYS386TGT) /* is gate descriptor pointer ? */ #define ISGDP(s) (IS286GDP(s) || IS386GDP(s)) /* is segment descriptor pointer ? */ #define ISSDP(s) (ISMEMSDP(s) || !ISGDP(s)) /* is system segment descriptor pointer ? */ #define ISSYSSDP(s) (!ISMEMSDP(s) && !ISGDP(s)) /* * 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 NRSVIDT 32 /* reserved entries for CPU exceptions */ /* * Entries in the Global Descriptor Table (GDT). * * NB: If you change GBIOSCODE/GBIOSDATA, you *must* rebuild arch/i386/ * bioscall/biostramp.inc, as that relies on GBIOSCODE/GBIOSDATA and a * normal kernel build does not rebuild it (it's merely included whole- * sale from i386/bioscall.s) * * Also, note that the GEXTBIOSDATA_SEL selector is special, as it maps * to the value 0x0040 (when created as a KPL global selector). Some * BIOSes reference the extended BIOS data area at segment 0040 in a non * relocatable fashion (even when in protected mode); mapping the zero page * via the GEXTBIOSDATA_SEL allows these buggy BIOSes to continue to work * under NetBSD. * * The order if the first 5 descriptors is special; the sysenter/sysexit * instructions depend on 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 GLDT_SEL 5 /* Default LDT descriptor */ #define GCPU_SEL 6 /* per-CPU segment */ #define GEXTBIOSDATA_SEL 8 /* magic to catch BIOS refs to EBDA */ #define GAPM32CODE_SEL 9 /* 3 APM segments must be consecutive */ #define GAPM16CODE_SEL 10 /* and in the specified order: code32 */ #define GAPMDATA_SEL 11 /* code16 and then data per APM spec */ #define GBIOSCODE_SEL 12 #define GBIOSDATA_SEL 13 #define GPNPBIOSCODE_SEL 14 #define GPNPBIOSDATA_SEL 15 #define GPNPBIOSSCRATCH_SEL 16 #define GPNPBIOSTRAMP_SEL 17 #define GTRAPTSS_SEL 18 #define GIPITSS_SEL 19 #define GUCODEBIG_SEL 20 /* User code with executable stack */ #define GUFS_SEL 21 /* Per-thread %fs */ #define GUGS_SEL 22 /* Per-thread %gs */ #define NGDT 23 /* * Entries in the Local Descriptor Table (LDT). * DO NOT ADD KERNEL DATA/CODE SEGMENTS TO THIS TABLE. */ #define LSYS5CALLS_SEL 0 /* iBCS system call gate */ #define LSYS5SIGR_SEL 1 /* iBCS sigreturn gate */ #define LUCODE_SEL 2 /* User code descriptor */ #define LUDATA_SEL 3 /* User data descriptor */ #define LSOL26CALLS_SEL 4 /* Solaris 2.6 system call gate */ #define LUCODEBIG_SEL 5 /* User code with executable stack */ #define LBSDICALLS_SEL 16 /* BSDI system call gate */ #define NLDT 17 #endif /* _I386_SEGMENTS_H_ */
