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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 | /* * arch/ppc/mm/fault.c * * PowerPC version * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) * * Derived from "arch/i386/mm/fault.c" * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds * * Modified by Cort Dougan and Paul Mackerras. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. */ #include <linux/config.h> #include <linux/signal.h> #include <linux/sched.h> #include <linux/kernel.h> #include <linux/errno.h> #include <linux/string.h> #include <linux/types.h> #include <linux/ptrace.h> #include <linux/mman.h> #include <linux/mm.h> #include <linux/interrupt.h> #include <asm/page.h> #include <asm/pgtable.h> #include <asm/mmu.h> #include <asm/mmu_context.h> #include <asm/system.h> #include <asm/uaccess.h> #if defined(CONFIG_XMON) || defined(CONFIG_KGDB) extern void (*debugger)(struct pt_regs *); extern void (*debugger_fault_handler)(struct pt_regs *); extern int (*debugger_dabr_match)(struct pt_regs *); int debugger_kernel_faults = 1; #endif unsigned long htab_reloads = 0; /* updated by head.S:hash_page() */ unsigned long htab_evicts = 0; /* updated by head.S:hash_page() */ unsigned long pte_misses = 0; /* updated by do_page_fault() */ unsigned long pte_errors = 0; /* updated by do_page_fault() */ unsigned int probingmem = 0; extern void die_if_kernel(char *, struct pt_regs *, long); void bad_page_fault(struct pt_regs *, unsigned long); void do_page_fault(struct pt_regs *, unsigned long, unsigned long); /* * The error_code parameter is DSISR for a data fault, SRR1 for * an instruction fault. */ void do_page_fault(struct pt_regs *regs, unsigned long address, unsigned long error_code) { struct vm_area_struct * vma; struct mm_struct *mm = current->mm; /*printk("address: %08lx nip:%08lx code: %08lx %s%s%s%s%s%s\n", address,regs->nip,error_code, (error_code&0x40000000)?"604 tlb&htab miss ":"", (error_code&0x20000000)?"603 tlbmiss ":"", (error_code&0x02000000)?"write ":"", (error_code&0x08000000)?"prot ":"", (error_code&0x80000000)?"I/O ":"", (regs->trap == 0x400)?"instr":"data" );*/ #if defined(CONFIG_XMON) || defined(CONFIG_KGDB) if (debugger_fault_handler && regs->trap == 0x300) { debugger_fault_handler(regs); return; } if (error_code & 0x00400000) { /* DABR match */ if (debugger_dabr_match(regs)) return; } #endif if (in_interrupt()) { static int complained; if (complained < 20) { ++complained; printk("page fault in interrupt handler, addr=%lx\n", address); show_regs(regs); #if defined(CONFIG_XMON) || defined(CONFIG_KGDB) if (debugger_kernel_faults) debugger(regs); #endif } } if (current == NULL) { bad_page_fault(regs, address); return; } down(&mm->mmap_sem); vma = find_vma(mm, address); if (!vma) goto bad_area; if (vma->vm_start <= address) goto good_area; if (!(vma->vm_flags & VM_GROWSDOWN)) goto bad_area; if (expand_stack(vma, address)) goto bad_area; good_area: #ifdef CONFIG_6xx if (error_code & 0x95700000) /* an error such as lwarx to I/O controller space, address matching DABR, eciwx, etc. */ #endif /* CONFIG_6xx */ #ifdef CONFIG_8xx /* The MPC8xx seems to always set 0x80000000, which is * "undefined". Of those that can be set, this is the only * one which seems bad. */ if (error_code & 0x10000000) /* Guarded storage error. */ #endif /* CONFIG_8xx */ goto bad_area; /* a write */ if (error_code & 0x02000000) { if (!(vma->vm_flags & VM_WRITE)) goto bad_area; /* a read */ } else { /* protection fault */ if (error_code & 0x08000000) goto bad_area; if (!(vma->vm_flags & (VM_READ | VM_EXEC))) goto bad_area; } handle_mm_fault(current, vma, address, error_code & 0x02000000); up(&mm->mmap_sem); /* * keep track of tlb+htab misses that are good addrs but * just need pte's created via handle_mm_fault() * -- Cort */ pte_misses++; return; bad_area: up(&mm->mmap_sem); pte_errors++; bad_page_fault(regs, address); } void bad_page_fault(struct pt_regs *regs, unsigned long address) { unsigned long fixup; if (user_mode(regs)) { force_sig(SIGSEGV, current); return; } /* Are we prepared to handle this fault? */ if ((fixup = search_exception_table(regs->nip)) != 0) { regs->nip = fixup; return; } /* kernel has accessed a bad area */ show_regs(regs); print_backtrace( (unsigned long *)regs->gpr[1] ); #if defined(CONFIG_XMON) || defined(CONFIG_KGDB) if (debugger_kernel_faults) debugger(regs); #endif panic("kernel access of bad area pc %lx lr %lx address %lX tsk %s/%d", regs->nip,regs->link,address,current->comm,current->pid); } #ifdef CONFIG_8xx /* * I need a va to pte function for the MPC8xx so I can set the cache * attributes on individual pages used by the Communication Processor * Module. */ pte_t *va_to_pte(struct task_struct *tsk, unsigned long address) { pgd_t *dir; pmd_t *pmd; pte_t *pte; dir = pgd_offset(tsk->mm, address & PAGE_MASK); if (dir) { pmd = pmd_offset(dir, address & PAGE_MASK); if (pmd && pmd_present(*pmd)) { pte = pte_offset(pmd, address & PAGE_MASK); if (pte && pte_present(*pte)) { return(pte); } } else { return (0); } } else { return (0); } return (0); } unsigned long va_to_phys(unsigned long address) { pgd_t *dir; pmd_t *pmd; pte_t *pte; dir = pgd_offset(current->mm, address & PAGE_MASK); if (dir) { pmd = pmd_offset(dir, address & PAGE_MASK); if (pmd && pmd_present(*pmd)) { pte = pte_offset(pmd, address & PAGE_MASK); if (pte && pte_present(*pte)) { return(pte_page(*pte) | (address & ~(PAGE_MASK-1))); } } else { return (0); } } else { return (0); } return (0); } void print_8xx_pte(struct mm_struct *mm, unsigned long addr) { pgd_t * pgd; pmd_t * pmd; pte_t * pte; printk(" pte @ 0x%8lx: ", addr); pgd = pgd_offset(mm, addr & PAGE_MASK); if (pgd) { pmd = pmd_offset(pgd, addr & PAGE_MASK); if (pmd && pmd_present(*pmd)) { pte = pte_offset(pmd, addr & PAGE_MASK); if (pte) { printk(" (0x%08lx)->(0x%08lx)->0x%08lx\n", (long)pgd, (long)pte, (long)pte_val(*pte)); #define pp ((long)pte_val(*pte)) printk(" RPN: %05x PP: %x SPS: %x SH: %x " "CI: %x v: %x\n", pp>>12, /* rpn */ (pp>>10)&3, /* pp */ (pp>>3)&1, /* small */ (pp>>2)&1, /* shared */ (pp>>1)&1, /* cache inhibit */ pp&1 /* valid */ ); #undef pp } else { printk("no pte\n"); } } else { printk("no pmd\n"); } } else { printk("no pgd\n"); } } int get_8xx_pte(struct mm_struct *mm, unsigned long addr) { pgd_t * pgd; pmd_t * pmd; pte_t * pte; int retval = 0; pgd = pgd_offset(mm, addr & PAGE_MASK); if (pgd) { pmd = pmd_offset(pgd, addr & PAGE_MASK); if (pmd && pmd_present(*pmd)) { pte = pte_offset(pmd, addr & PAGE_MASK); if (pte) { retval = (int)pte_val(*pte); } } } return(retval); } #endif /* CONFIG_8xx */ #if 0 /* * Misc debugging functions. Please leave them here. -- Cort */ void print_pte(struct _PTE p) { printk( "%08x %08x vsid: %06x h: %01x api: %02x rpn: %05x rcwimg: %d%d%d%d%d%d pp: %02x\n", *((unsigned long *)(&p)), *((long *)&p+1), p.vsid, p.h, p.api, p.rpn, p.r,p.c,p.w,p.i,p.m,p.g,p.pp); } /* * Search the hw hash table for a mapping to the given physical * address. -- Cort */ unsigned long htab_phys_to_va(unsigned long address) { extern PTE *Hash, *Hash_end; PTE *ptr; for ( ptr = Hash ; ptr < Hash_end ; ptr++ ) { if ( ptr->rpn == (address>>12) ) printk("phys %08lX -> va ???\n", address); } } #endif |