pmap.h revision 1.11
1 /* $NetBSD: pmap.h,v 1.11 2001/07/28 18:12:44 chris Exp $ */ 2 3 /* 4 * Copyright (c) 1994,1995 Mark Brinicombe. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by Mark Brinicombe 18 * 4. The name of the author may not be used to endorse or promote products 19 * derived from this software without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 #ifndef _ARM32_PMAP_H_ 34 #define _ARM32_PMAP_H_ 35 36 #include <machine/cpufunc.h> 37 #include <machine/pte.h> 38 39 /* 40 * a pmap describes a processes' 4GB virtual address space. this 41 * virtual address space can be broken up into 4096 1MB regions which 42 * are described by PDEs in the PDP. the PDEs are defined as follows: 43 * 44 * (ranges are inclusive -> exclusive, just like vm_map_entry start/end) 45 * (the following assumes that KERNBASE is 0xf0000000) 46 * 47 * PDE#s VA range usage 48 * 0->3835 0x0 -> 0xefc00000 user address space 49 * 3836->3839 0xefc00000-> recursive mapping of PDP (used for 50 * 0xf0000000 linear mapping of PTPs) 51 * 3840->3851 0xf0000000-> kernel text address space (constant 52 * 0xf0c00000 across all pmap's/processes) 53 * 3852->3855 0xf0c00000-> "alternate" recursive PDP mapping 54 * 0xf1000000 (for other pmaps) 55 * 3856->4095 0xf1000000-> KVM and device mappings, constant 56 * 0x00000000 across all pmaps 57 * 58 * The maths works out that to then map each 1MB block into 4k pages requires 59 * 256 entries, of 4 bytes each, totaling 1k per 1MB. However as we use 4k 60 * pages we allocate 4 PDE's at a time, allocating the same access permissions 61 * to them all. This means we only need 1024 entries in the page table page 62 * table, IE we use 1 4k page to linearly map all the other page tables used. 63 */ 64 65 66 67 /* 68 * Data structures used by pmap 69 */ 70 71 /* 72 * Structure that describes a Level 1 page table and the flags 73 * associated with it. 74 */ 75 struct l1pt { 76 SIMPLEQ_ENTRY(l1pt) pt_queue; /* Queue pointers */ 77 struct pglist pt_plist; /* Allocated page list */ 78 vaddr_t pt_va; /* Allocated virtual address */ 79 int pt_flags; /* Flags */ 80 }; 81 #define PTFLAG_STATIC 1 /* Statically allocated */ 82 #define PTFLAG_KPT 2 /* Kernel pt's are mapped */ 83 #define PTFLAG_CLEAN 4 /* L1 is clean */ 84 85 /* 86 * The pmap structure itself. 87 */ 88 struct pmap { 89 pd_entry_t *pm_pdir; /* KVA of page directory */ 90 struct l1pt *pm_l1pt; /* L1 descriptor */ 91 paddr_t pm_pptpt; /* PA of pt's page table */ 92 vaddr_t pm_vptpt; /* VA of pt's page table */ 93 short pm_count; /* pmap reference count */ 94 struct simplelock pm_lock; /* lock on pmap */ 95 struct pmap_statistics pm_stats; /* pmap statistics */ 96 }; 97 98 typedef struct pmap *pmap_t; 99 100 /* 101 * For each struct vm_page, there is a list of all currently valid virtual 102 * mappings of that page. An entry is a pv_entry_t, the list is pv_table. 103 */ 104 typedef struct pv_entry { 105 struct pv_entry *pv_next; /* next pv_entry */ 106 struct pmap *pv_pmap; /* pmap where mapping lies */ 107 vaddr_t pv_va; /* virtual address for mapping */ 108 int pv_flags; /* flags */ 109 } *pv_entry_t; 110 111 /* 112 * A pv_page_info struture looks like this. It is used to contain status 113 * information for pv_entry freelists. 114 */ 115 struct pv_page; 116 117 struct pv_page_info { 118 TAILQ_ENTRY(pv_page) pgi_list; 119 struct pv_entry *pgi_freelist; 120 int pgi_nfree; 121 }; 122 123 /* 124 * A pv_page itself looks like this. pv_entries are requested from the VM a 125 * pv_page at a time. 126 * 127 * We also define a macro that states the number of pv_entries per page 128 * allocated. 129 */ 130 #define NPVPPG ((NBPG - sizeof(struct pv_page_info)) / sizeof(struct pv_entry)) 131 132 struct pv_page { 133 struct pv_page_info pvp_pgi; 134 struct pv_entry pvp_pv[NPVPPG]; 135 }; 136 137 /* 138 * Page hooks. I'll eliminate these sometime soon :-) 139 * 140 * For speed we store the both the virtual address and the page table 141 * entry address for each page hook. 142 */ 143 typedef struct { 144 vaddr_t va; 145 pt_entry_t *pte; 146 } pagehook_t; 147 148 /* 149 * Physical / virtual address structure. In a number of places (particularly 150 * during bootstrapping) we need to keep track of the physical and virtual 151 * addresses of various pages 152 */ 153 typedef struct { 154 paddr_t pv_pa; 155 vaddr_t pv_va; 156 } pv_addr_t; 157 158 /* 159 * _KERNEL specific macros, functions and prototypes 160 */ 161 162 #ifdef _KERNEL 163 164 /* 165 * Commonly referenced structures 166 */ 167 extern pv_entry_t pv_table; /* Phys to virt mappings, per page. */ 168 extern struct pmap kernel_pmap_store; 169 extern int pmap_debug_level; /* Only exists if PMAP_DEBUG */ 170 171 /* 172 * Macros that we need to export 173 */ 174 #define pmap_kernel() (&kernel_pmap_store) 175 #define pmap_update() /* nothing (yet) */ 176 #define pmap_resident_count(pmap) ((pmap)->pm_stats.resident_count) 177 #define pmap_wired_count(pmap) ((pmap)->pm_stats.wired_count) 178 179 #define pmap_phys_address(ppn) (arm_page_to_byte((ppn))) 180 181 /* 182 * Functions that we need to export 183 */ 184 extern boolean_t pmap_testbit __P((paddr_t, int)); 185 extern void pmap_changebit __P((paddr_t, int, int)); 186 extern vaddr_t pmap_map __P((vaddr_t, vaddr_t, vaddr_t, int)); 187 extern void pmap_procwr __P((struct proc *, vaddr_t, int)); 188 #define PMAP_NEED_PROCWR 189 190 /* 191 * Functions we use internally 192 */ 193 extern void pmap_bootstrap __P((pd_entry_t *, pv_addr_t)); 194 extern void pmap_debug __P((int)); 195 extern int pmap_handled_emulation __P((struct pmap *, vaddr_t)); 196 extern int pmap_modified_emulation __P((struct pmap *, vaddr_t)); 197 extern void pmap_postinit __P((void)); 198 extern pt_entry_t *pmap_pte __P((struct pmap *, vaddr_t)); 199 200 #endif /* _KERNEL */ 201 202 /* 203 * Useful macros and constants 204 */ 205 206 /* Virtual address to page table entry */ 207 #define vtopte(va) \ 208 ((pt_entry_t *)(PROCESS_PAGE_TBLS_BASE + \ 209 (arm_byte_to_page((unsigned int)(va)) << 2))) 210 211 /* Virtual address to physical address */ 212 #define vtophys(va) \ 213 ((*vtopte(va) & PG_FRAME) | ((unsigned int)(va) & ~PG_FRAME)) 214 215 /* L1 and L2 page table macros */ 216 #define pmap_pde(m, v) (&((m)->pm_pdir[((vaddr_t)(v) >> PDSHIFT)&4095])) 217 #define pmap_pte_pa(pte) (*(pte) & PG_FRAME) 218 #define pmap_pde_v(pde) (*(pde) != 0) 219 #define pmap_pte_v(pte) (*(pte) != 0) 220 221 /* Size of the kernel part of the L1 page table */ 222 #define KERNEL_PD_SIZE \ 223 (PD_SIZE - (KERNEL_SPACE_START >> PDSHIFT) * sizeof(pd_entry_t)) 224 225 #endif /* _ARM32_PMAP_H_ */ 226
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