Adrian Bunk | 88278ca | 2008-05-19 16:53:02 -0700 | [diff] [blame] | 1 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2 | * fault.c: Page fault handlers for the Sparc. |
| 3 | * |
| 4 | * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu) |
| 5 | * Copyright (C) 1996 Eddie C. Dost (ecd@skynet.be) |
| 6 | * Copyright (C) 1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz) |
| 7 | */ |
| 8 | |
| 9 | #include <asm/head.h> |
| 10 | |
| 11 | #include <linux/string.h> |
| 12 | #include <linux/types.h> |
| 13 | #include <linux/sched.h> |
| 14 | #include <linux/ptrace.h> |
| 15 | #include <linux/mman.h> |
| 16 | #include <linux/threads.h> |
| 17 | #include <linux/kernel.h> |
| 18 | #include <linux/signal.h> |
| 19 | #include <linux/mm.h> |
| 20 | #include <linux/smp.h> |
David S. Miller | a084b66 | 2010-01-20 03:04:14 -0800 | [diff] [blame] | 21 | #include <linux/perf_event.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 22 | #include <linux/interrupt.h> |
| 23 | #include <linux/module.h> |
Christoph Hellwig | 1eeb66a | 2007-05-08 00:27:03 -0700 | [diff] [blame] | 24 | #include <linux/kdebug.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 25 | |
| 26 | #include <asm/system.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 27 | #include <asm/page.h> |
| 28 | #include <asm/pgtable.h> |
| 29 | #include <asm/memreg.h> |
| 30 | #include <asm/openprom.h> |
| 31 | #include <asm/oplib.h> |
| 32 | #include <asm/smp.h> |
| 33 | #include <asm/traps.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 34 | #include <asm/uaccess.h> |
| 35 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 36 | extern int prom_node_root; |
| 37 | |
David S. Miller | 4b17764 | 2010-03-01 00:02:23 -0800 | [diff] [blame] | 38 | int show_unhandled_signals = 1; |
| 39 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 40 | /* At boot time we determine these two values necessary for setting |
| 41 | * up the segment maps and page table entries (pte's). |
| 42 | */ |
| 43 | |
| 44 | int num_segmaps, num_contexts; |
| 45 | int invalid_segment; |
| 46 | |
| 47 | /* various Virtual Address Cache parameters we find at boot time... */ |
| 48 | |
| 49 | int vac_size, vac_linesize, vac_do_hw_vac_flushes; |
| 50 | int vac_entries_per_context, vac_entries_per_segment; |
| 51 | int vac_entries_per_page; |
| 52 | |
David S. Miller | 9f2b2a5 | 2008-05-01 22:28:17 -0700 | [diff] [blame] | 53 | /* Return how much physical memory we have. */ |
| 54 | unsigned long probe_memory(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 55 | { |
David S. Miller | 9f2b2a5 | 2008-05-01 22:28:17 -0700 | [diff] [blame] | 56 | unsigned long total = 0; |
| 57 | int i; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 58 | |
David S. Miller | 9f2b2a5 | 2008-05-01 22:28:17 -0700 | [diff] [blame] | 59 | for (i = 0; sp_banks[i].num_bytes; i++) |
| 60 | total += sp_banks[i].num_bytes; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 61 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 62 | return total; |
| 63 | } |
| 64 | |
| 65 | extern void sun4c_complete_all_stores(void); |
| 66 | |
| 67 | /* Whee, a level 15 NMI interrupt memory error. Let's have fun... */ |
| 68 | asmlinkage void sparc_lvl15_nmi(struct pt_regs *regs, unsigned long serr, |
| 69 | unsigned long svaddr, unsigned long aerr, |
| 70 | unsigned long avaddr) |
| 71 | { |
| 72 | sun4c_complete_all_stores(); |
| 73 | printk("FAULT: NMI received\n"); |
| 74 | printk("SREGS: Synchronous Error %08lx\n", serr); |
| 75 | printk(" Synchronous Vaddr %08lx\n", svaddr); |
| 76 | printk(" Asynchronous Error %08lx\n", aerr); |
| 77 | printk(" Asynchronous Vaddr %08lx\n", avaddr); |
| 78 | if (sun4c_memerr_reg) |
| 79 | printk(" Memory Parity Error %08lx\n", *sun4c_memerr_reg); |
| 80 | printk("REGISTER DUMP:\n"); |
| 81 | show_regs(regs); |
| 82 | prom_halt(); |
| 83 | } |
| 84 | |
| 85 | static void unhandled_fault(unsigned long, struct task_struct *, |
| 86 | struct pt_regs *) __attribute__ ((noreturn)); |
| 87 | |
| 88 | static void unhandled_fault(unsigned long address, struct task_struct *tsk, |
| 89 | struct pt_regs *regs) |
| 90 | { |
| 91 | if((unsigned long) address < PAGE_SIZE) { |
| 92 | printk(KERN_ALERT |
| 93 | "Unable to handle kernel NULL pointer dereference\n"); |
| 94 | } else { |
| 95 | printk(KERN_ALERT "Unable to handle kernel paging request " |
| 96 | "at virtual address %08lx\n", address); |
| 97 | } |
| 98 | printk(KERN_ALERT "tsk->{mm,active_mm}->context = %08lx\n", |
| 99 | (tsk->mm ? tsk->mm->context : tsk->active_mm->context)); |
| 100 | printk(KERN_ALERT "tsk->{mm,active_mm}->pgd = %08lx\n", |
| 101 | (tsk->mm ? (unsigned long) tsk->mm->pgd : |
| 102 | (unsigned long) tsk->active_mm->pgd)); |
| 103 | die_if_kernel("Oops", regs); |
| 104 | } |
| 105 | |
| 106 | asmlinkage int lookup_fault(unsigned long pc, unsigned long ret_pc, |
| 107 | unsigned long address) |
| 108 | { |
| 109 | struct pt_regs regs; |
| 110 | unsigned long g2; |
| 111 | unsigned int insn; |
| 112 | int i; |
| 113 | |
| 114 | i = search_extables_range(ret_pc, &g2); |
| 115 | switch (i) { |
| 116 | case 3: |
| 117 | /* load & store will be handled by fixup */ |
| 118 | return 3; |
| 119 | |
| 120 | case 1: |
| 121 | /* store will be handled by fixup, load will bump out */ |
| 122 | /* for _to_ macros */ |
| 123 | insn = *((unsigned int *) pc); |
| 124 | if ((insn >> 21) & 1) |
| 125 | return 1; |
| 126 | break; |
| 127 | |
| 128 | case 2: |
| 129 | /* load will be handled by fixup, store will bump out */ |
| 130 | /* for _from_ macros */ |
| 131 | insn = *((unsigned int *) pc); |
| 132 | if (!((insn >> 21) & 1) || ((insn>>19)&0x3f) == 15) |
| 133 | return 2; |
| 134 | break; |
| 135 | |
| 136 | default: |
| 137 | break; |
| 138 | }; |
| 139 | |
| 140 | memset(®s, 0, sizeof (regs)); |
| 141 | regs.pc = pc; |
| 142 | regs.npc = pc + 4; |
| 143 | __asm__ __volatile__( |
| 144 | "rd %%psr, %0\n\t" |
| 145 | "nop\n\t" |
| 146 | "nop\n\t" |
| 147 | "nop\n" : "=r" (regs.psr)); |
| 148 | unhandled_fault(address, current, ®s); |
| 149 | |
| 150 | /* Not reached */ |
| 151 | return 0; |
| 152 | } |
| 153 | |
David S. Miller | 4b17764 | 2010-03-01 00:02:23 -0800 | [diff] [blame] | 154 | static inline void |
| 155 | show_signal_msg(struct pt_regs *regs, int sig, int code, |
| 156 | unsigned long address, struct task_struct *tsk) |
| 157 | { |
| 158 | if (!unhandled_signal(tsk, sig)) |
| 159 | return; |
| 160 | |
| 161 | if (!printk_ratelimit()) |
| 162 | return; |
| 163 | |
| 164 | printk("%s%s[%d]: segfault at %lx ip %p (rpc %p) sp %p error %x", |
| 165 | task_pid_nr(tsk) > 1 ? KERN_INFO : KERN_EMERG, |
| 166 | tsk->comm, task_pid_nr(tsk), address, |
| 167 | (void *)regs->pc, (void *)regs->u_regs[UREG_I7], |
| 168 | (void *)regs->u_regs[UREG_FP], code); |
| 169 | |
| 170 | print_vma_addr(KERN_CONT " in ", regs->pc); |
| 171 | |
| 172 | printk(KERN_CONT "\n"); |
| 173 | } |
| 174 | |
| 175 | static void __do_fault_siginfo(int code, int sig, struct pt_regs *regs, |
| 176 | unsigned long addr) |
| 177 | { |
| 178 | siginfo_t info; |
| 179 | |
| 180 | info.si_signo = sig; |
| 181 | info.si_code = code; |
| 182 | info.si_errno = 0; |
| 183 | info.si_addr = (void __user *) addr; |
| 184 | info.si_trapno = 0; |
| 185 | |
| 186 | if (unlikely(show_unhandled_signals)) |
| 187 | show_signal_msg(regs, sig, info.si_code, |
| 188 | addr, current); |
| 189 | |
| 190 | force_sig_info (sig, &info, current); |
| 191 | } |
| 192 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 193 | extern unsigned long safe_compute_effective_address(struct pt_regs *, |
| 194 | unsigned int); |
| 195 | |
| 196 | static unsigned long compute_si_addr(struct pt_regs *regs, int text_fault) |
| 197 | { |
| 198 | unsigned int insn; |
| 199 | |
| 200 | if (text_fault) |
| 201 | return regs->pc; |
| 202 | |
| 203 | if (regs->psr & PSR_PS) { |
| 204 | insn = *(unsigned int *) regs->pc; |
| 205 | } else { |
| 206 | __get_user(insn, (unsigned int *) regs->pc); |
| 207 | } |
| 208 | |
| 209 | return safe_compute_effective_address(regs, insn); |
| 210 | } |
| 211 | |
David S. Miller | 4b17764 | 2010-03-01 00:02:23 -0800 | [diff] [blame] | 212 | static noinline void do_fault_siginfo(int code, int sig, struct pt_regs *regs, |
| 213 | int text_fault) |
| 214 | { |
| 215 | unsigned long addr = compute_si_addr(regs, text_fault); |
| 216 | |
| 217 | __do_fault_siginfo(code, sig, regs, addr); |
| 218 | } |
| 219 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 220 | asmlinkage void do_sparc_fault(struct pt_regs *regs, int text_fault, int write, |
| 221 | unsigned long address) |
| 222 | { |
| 223 | struct vm_area_struct *vma; |
| 224 | struct task_struct *tsk = current; |
| 225 | struct mm_struct *mm = tsk->mm; |
| 226 | unsigned int fixup; |
| 227 | unsigned long g2; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 228 | int from_user = !(regs->psr & PSR_PS); |
David S. Miller | 4b17764 | 2010-03-01 00:02:23 -0800 | [diff] [blame] | 229 | int fault, code; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 230 | |
| 231 | if(text_fault) |
| 232 | address = regs->pc; |
| 233 | |
| 234 | /* |
| 235 | * We fault-in kernel-space virtual memory on-demand. The |
| 236 | * 'reference' page table is init_mm.pgd. |
| 237 | * |
| 238 | * NOTE! We MUST NOT take any locks for this case. We may |
| 239 | * be in an interrupt or a critical region, and should |
| 240 | * only copy the information from the master page table, |
| 241 | * nothing more. |
| 242 | */ |
David S. Miller | c816be7 | 2011-03-09 13:00:47 -0800 | [diff] [blame] | 243 | code = SEGV_MAPERR; |
Adrian Bunk | 5110bd2 | 2008-08-31 20:59:37 -0700 | [diff] [blame] | 244 | if (!ARCH_SUN4C && address >= TASK_SIZE) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 245 | goto vmalloc_fault; |
| 246 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 247 | /* |
| 248 | * If we're in an interrupt or have no user |
| 249 | * context, we must not take the fault.. |
| 250 | */ |
| 251 | if (in_atomic() || !mm) |
| 252 | goto no_context; |
| 253 | |
David S. Miller | a084b66 | 2010-01-20 03:04:14 -0800 | [diff] [blame] | 254 | perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, 0, regs, address); |
| 255 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 256 | down_read(&mm->mmap_sem); |
| 257 | |
| 258 | /* |
| 259 | * The kernel referencing a bad kernel pointer can lock up |
| 260 | * a sun4c machine completely, so we must attempt recovery. |
| 261 | */ |
| 262 | if(!from_user && address >= PAGE_OFFSET) |
| 263 | goto bad_area; |
| 264 | |
| 265 | vma = find_vma(mm, address); |
| 266 | if(!vma) |
| 267 | goto bad_area; |
| 268 | if(vma->vm_start <= address) |
| 269 | goto good_area; |
| 270 | if(!(vma->vm_flags & VM_GROWSDOWN)) |
| 271 | goto bad_area; |
| 272 | if(expand_stack(vma, address)) |
| 273 | goto bad_area; |
| 274 | /* |
| 275 | * Ok, we have a good vm_area for this memory access, so |
| 276 | * we can handle it.. |
| 277 | */ |
| 278 | good_area: |
David S. Miller | 4b17764 | 2010-03-01 00:02:23 -0800 | [diff] [blame] | 279 | code = SEGV_ACCERR; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 280 | if(write) { |
| 281 | if(!(vma->vm_flags & VM_WRITE)) |
| 282 | goto bad_area; |
| 283 | } else { |
| 284 | /* Allow reads even for write-only mappings */ |
| 285 | if(!(vma->vm_flags & (VM_READ | VM_EXEC))) |
| 286 | goto bad_area; |
| 287 | } |
| 288 | |
| 289 | /* |
| 290 | * If for any reason at all we couldn't handle the fault, |
| 291 | * make sure we exit gracefully rather than endlessly redo |
| 292 | * the fault. |
| 293 | */ |
Linus Torvalds | d06063c | 2009-04-10 09:01:23 -0700 | [diff] [blame] | 294 | fault = handle_mm_fault(mm, vma, address, write ? FAULT_FLAG_WRITE : 0); |
Nick Piggin | 83c5407 | 2007-07-19 01:47:05 -0700 | [diff] [blame] | 295 | if (unlikely(fault & VM_FAULT_ERROR)) { |
| 296 | if (fault & VM_FAULT_OOM) |
| 297 | goto out_of_memory; |
| 298 | else if (fault & VM_FAULT_SIGBUS) |
| 299 | goto do_sigbus; |
| 300 | BUG(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 301 | } |
David S. Miller | a084b66 | 2010-01-20 03:04:14 -0800 | [diff] [blame] | 302 | if (fault & VM_FAULT_MAJOR) { |
Nick Piggin | 83c5407 | 2007-07-19 01:47:05 -0700 | [diff] [blame] | 303 | current->maj_flt++; |
David S. Miller | a084b66 | 2010-01-20 03:04:14 -0800 | [diff] [blame] | 304 | perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ, 1, 0, |
| 305 | regs, address); |
| 306 | } else { |
Nick Piggin | 83c5407 | 2007-07-19 01:47:05 -0700 | [diff] [blame] | 307 | current->min_flt++; |
David S. Miller | a084b66 | 2010-01-20 03:04:14 -0800 | [diff] [blame] | 308 | perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, 1, 0, |
| 309 | regs, address); |
| 310 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 311 | up_read(&mm->mmap_sem); |
| 312 | return; |
| 313 | |
| 314 | /* |
| 315 | * Something tried to access memory that isn't in our memory map.. |
| 316 | * Fix it, but check if it's kernel or user first.. |
| 317 | */ |
| 318 | bad_area: |
| 319 | up_read(&mm->mmap_sem); |
| 320 | |
| 321 | bad_area_nosemaphore: |
| 322 | /* User mode accesses just cause a SIGSEGV */ |
David S. Miller | 4b17764 | 2010-03-01 00:02:23 -0800 | [diff] [blame] | 323 | if (from_user) { |
| 324 | do_fault_siginfo(code, SIGSEGV, regs, text_fault); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 325 | return; |
| 326 | } |
| 327 | |
| 328 | /* Is this in ex_table? */ |
| 329 | no_context: |
| 330 | g2 = regs->u_regs[UREG_G2]; |
Sam Ravnborg | 0157141 | 2009-01-06 12:52:41 -0800 | [diff] [blame] | 331 | if (!from_user) { |
| 332 | fixup = search_extables_range(regs->pc, &g2); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 333 | if (fixup > 10) { /* Values below are reserved for other things */ |
| 334 | extern const unsigned __memset_start[]; |
| 335 | extern const unsigned __memset_end[]; |
| 336 | extern const unsigned __csum_partial_copy_start[]; |
| 337 | extern const unsigned __csum_partial_copy_end[]; |
| 338 | |
| 339 | #ifdef DEBUG_EXCEPTIONS |
| 340 | printk("Exception: PC<%08lx> faddr<%08lx>\n", regs->pc, address); |
| 341 | printk("EX_TABLE: insn<%08lx> fixup<%08x> g2<%08lx>\n", |
| 342 | regs->pc, fixup, g2); |
| 343 | #endif |
| 344 | if ((regs->pc >= (unsigned long)__memset_start && |
| 345 | regs->pc < (unsigned long)__memset_end) || |
| 346 | (regs->pc >= (unsigned long)__csum_partial_copy_start && |
| 347 | regs->pc < (unsigned long)__csum_partial_copy_end)) { |
| 348 | regs->u_regs[UREG_I4] = address; |
| 349 | regs->u_regs[UREG_I5] = regs->pc; |
| 350 | } |
| 351 | regs->u_regs[UREG_G2] = g2; |
| 352 | regs->pc = fixup; |
| 353 | regs->npc = regs->pc + 4; |
| 354 | return; |
| 355 | } |
| 356 | } |
| 357 | |
| 358 | unhandled_fault (address, tsk, regs); |
| 359 | do_exit(SIGKILL); |
| 360 | |
| 361 | /* |
| 362 | * We ran out of memory, or some other thing happened to us that made |
| 363 | * us unable to handle the page fault gracefully. |
| 364 | */ |
| 365 | out_of_memory: |
| 366 | up_read(&mm->mmap_sem); |
David S. Miller | a923c28 | 2009-08-02 19:17:15 -0700 | [diff] [blame] | 367 | if (from_user) { |
| 368 | pagefault_out_of_memory(); |
| 369 | return; |
| 370 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 371 | goto no_context; |
| 372 | |
| 373 | do_sigbus: |
| 374 | up_read(&mm->mmap_sem); |
David S. Miller | 4b17764 | 2010-03-01 00:02:23 -0800 | [diff] [blame] | 375 | do_fault_siginfo(BUS_ADRERR, SIGBUS, regs, text_fault); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 376 | if (!from_user) |
| 377 | goto no_context; |
| 378 | |
| 379 | vmalloc_fault: |
| 380 | { |
| 381 | /* |
| 382 | * Synchronize this task's top level page-table |
| 383 | * with the 'reference' page table. |
| 384 | */ |
| 385 | int offset = pgd_index(address); |
| 386 | pgd_t *pgd, *pgd_k; |
| 387 | pmd_t *pmd, *pmd_k; |
| 388 | |
| 389 | pgd = tsk->active_mm->pgd + offset; |
| 390 | pgd_k = init_mm.pgd + offset; |
| 391 | |
| 392 | if (!pgd_present(*pgd)) { |
| 393 | if (!pgd_present(*pgd_k)) |
| 394 | goto bad_area_nosemaphore; |
| 395 | pgd_val(*pgd) = pgd_val(*pgd_k); |
| 396 | return; |
| 397 | } |
| 398 | |
| 399 | pmd = pmd_offset(pgd, address); |
| 400 | pmd_k = pmd_offset(pgd_k, address); |
| 401 | |
| 402 | if (pmd_present(*pmd) || !pmd_present(*pmd_k)) |
| 403 | goto bad_area_nosemaphore; |
| 404 | *pmd = *pmd_k; |
| 405 | return; |
| 406 | } |
| 407 | } |
| 408 | |
| 409 | asmlinkage void do_sun4c_fault(struct pt_regs *regs, int text_fault, int write, |
| 410 | unsigned long address) |
| 411 | { |
| 412 | extern void sun4c_update_mmu_cache(struct vm_area_struct *, |
Russell King | 4b3073e | 2009-12-18 16:40:18 +0000 | [diff] [blame] | 413 | unsigned long,pte_t *); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 414 | extern pte_t *sun4c_pte_offset_kernel(pmd_t *,unsigned long); |
| 415 | struct task_struct *tsk = current; |
| 416 | struct mm_struct *mm = tsk->mm; |
| 417 | pgd_t *pgdp; |
| 418 | pte_t *ptep; |
| 419 | |
| 420 | if (text_fault) { |
| 421 | address = regs->pc; |
| 422 | } else if (!write && |
| 423 | !(regs->psr & PSR_PS)) { |
| 424 | unsigned int insn, __user *ip; |
| 425 | |
| 426 | ip = (unsigned int __user *)regs->pc; |
| 427 | if (!get_user(insn, ip)) { |
| 428 | if ((insn & 0xc1680000) == 0xc0680000) |
| 429 | write = 1; |
| 430 | } |
| 431 | } |
| 432 | |
| 433 | if (!mm) { |
| 434 | /* We are oopsing. */ |
| 435 | do_sparc_fault(regs, text_fault, write, address); |
| 436 | BUG(); /* P3 Oops already, you bitch */ |
| 437 | } |
| 438 | |
| 439 | pgdp = pgd_offset(mm, address); |
| 440 | ptep = sun4c_pte_offset_kernel((pmd_t *) pgdp, address); |
| 441 | |
| 442 | if (pgd_val(*pgdp)) { |
| 443 | if (write) { |
| 444 | if ((pte_val(*ptep) & (_SUN4C_PAGE_WRITE|_SUN4C_PAGE_PRESENT)) |
| 445 | == (_SUN4C_PAGE_WRITE|_SUN4C_PAGE_PRESENT)) { |
| 446 | unsigned long flags; |
| 447 | |
| 448 | *ptep = __pte(pte_val(*ptep) | _SUN4C_PAGE_ACCESSED | |
| 449 | _SUN4C_PAGE_MODIFIED | |
| 450 | _SUN4C_PAGE_VALID | |
| 451 | _SUN4C_PAGE_DIRTY); |
| 452 | |
| 453 | local_irq_save(flags); |
| 454 | if (sun4c_get_segmap(address) != invalid_segment) { |
| 455 | sun4c_put_pte(address, pte_val(*ptep)); |
| 456 | local_irq_restore(flags); |
| 457 | return; |
| 458 | } |
| 459 | local_irq_restore(flags); |
| 460 | } |
| 461 | } else { |
| 462 | if ((pte_val(*ptep) & (_SUN4C_PAGE_READ|_SUN4C_PAGE_PRESENT)) |
| 463 | == (_SUN4C_PAGE_READ|_SUN4C_PAGE_PRESENT)) { |
| 464 | unsigned long flags; |
| 465 | |
| 466 | *ptep = __pte(pte_val(*ptep) | _SUN4C_PAGE_ACCESSED | |
| 467 | _SUN4C_PAGE_VALID); |
| 468 | |
| 469 | local_irq_save(flags); |
| 470 | if (sun4c_get_segmap(address) != invalid_segment) { |
| 471 | sun4c_put_pte(address, pte_val(*ptep)); |
| 472 | local_irq_restore(flags); |
| 473 | return; |
| 474 | } |
| 475 | local_irq_restore(flags); |
| 476 | } |
| 477 | } |
| 478 | } |
| 479 | |
| 480 | /* This conditional is 'interesting'. */ |
| 481 | if (pgd_val(*pgdp) && !(write && !(pte_val(*ptep) & _SUN4C_PAGE_WRITE)) |
| 482 | && (pte_val(*ptep) & _SUN4C_PAGE_VALID)) |
| 483 | /* Note: It is safe to not grab the MMAP semaphore here because |
| 484 | * we know that update_mmu_cache() will not sleep for |
| 485 | * any reason (at least not in the current implementation) |
| 486 | * and therefore there is no danger of another thread getting |
| 487 | * on the CPU and doing a shrink_mmap() on this vma. |
| 488 | */ |
| 489 | sun4c_update_mmu_cache (find_vma(current->mm, address), address, |
Russell King | 4b3073e | 2009-12-18 16:40:18 +0000 | [diff] [blame] | 490 | ptep); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 491 | else |
| 492 | do_sparc_fault(regs, text_fault, write, address); |
| 493 | } |
| 494 | |
| 495 | /* This always deals with user addresses. */ |
Adrian Bunk | 50215d6 | 2008-06-05 11:41:51 -0700 | [diff] [blame] | 496 | static void force_user_fault(unsigned long address, int write) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 497 | { |
| 498 | struct vm_area_struct *vma; |
| 499 | struct task_struct *tsk = current; |
| 500 | struct mm_struct *mm = tsk->mm; |
David S. Miller | 4b17764 | 2010-03-01 00:02:23 -0800 | [diff] [blame] | 501 | int code; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 502 | |
David S. Miller | 4b17764 | 2010-03-01 00:02:23 -0800 | [diff] [blame] | 503 | code = SEGV_MAPERR; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 504 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 505 | down_read(&mm->mmap_sem); |
| 506 | vma = find_vma(mm, address); |
| 507 | if(!vma) |
| 508 | goto bad_area; |
| 509 | if(vma->vm_start <= address) |
| 510 | goto good_area; |
| 511 | if(!(vma->vm_flags & VM_GROWSDOWN)) |
| 512 | goto bad_area; |
| 513 | if(expand_stack(vma, address)) |
| 514 | goto bad_area; |
| 515 | good_area: |
David S. Miller | 4b17764 | 2010-03-01 00:02:23 -0800 | [diff] [blame] | 516 | code = SEGV_ACCERR; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 517 | if(write) { |
| 518 | if(!(vma->vm_flags & VM_WRITE)) |
| 519 | goto bad_area; |
| 520 | } else { |
| 521 | if(!(vma->vm_flags & (VM_READ | VM_EXEC))) |
| 522 | goto bad_area; |
| 523 | } |
Linus Torvalds | d06063c | 2009-04-10 09:01:23 -0700 | [diff] [blame] | 524 | switch (handle_mm_fault(mm, vma, address, write ? FAULT_FLAG_WRITE : 0)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 525 | case VM_FAULT_SIGBUS: |
| 526 | case VM_FAULT_OOM: |
| 527 | goto do_sigbus; |
| 528 | } |
| 529 | up_read(&mm->mmap_sem); |
| 530 | return; |
| 531 | bad_area: |
| 532 | up_read(&mm->mmap_sem); |
David S. Miller | 4b17764 | 2010-03-01 00:02:23 -0800 | [diff] [blame] | 533 | __do_fault_siginfo(code, SIGSEGV, tsk->thread.kregs, address); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 534 | return; |
| 535 | |
| 536 | do_sigbus: |
| 537 | up_read(&mm->mmap_sem); |
David S. Miller | 4b17764 | 2010-03-01 00:02:23 -0800 | [diff] [blame] | 538 | __do_fault_siginfo(BUS_ADRERR, SIGBUS, tsk->thread.kregs, address); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 539 | } |
| 540 | |
David S. Miller | 9088333 | 2010-09-23 22:06:47 -0700 | [diff] [blame] | 541 | static void check_stack_aligned(unsigned long sp) |
| 542 | { |
| 543 | if (sp & 0x7UL) |
| 544 | force_sig(SIGILL, current); |
| 545 | } |
| 546 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 547 | void window_overflow_fault(void) |
| 548 | { |
| 549 | unsigned long sp; |
| 550 | |
| 551 | sp = current_thread_info()->rwbuf_stkptrs[0]; |
| 552 | if(((sp + 0x38) & PAGE_MASK) != (sp & PAGE_MASK)) |
| 553 | force_user_fault(sp + 0x38, 1); |
| 554 | force_user_fault(sp, 1); |
David S. Miller | 9088333 | 2010-09-23 22:06:47 -0700 | [diff] [blame] | 555 | |
| 556 | check_stack_aligned(sp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 557 | } |
| 558 | |
| 559 | void window_underflow_fault(unsigned long sp) |
| 560 | { |
| 561 | if(((sp + 0x38) & PAGE_MASK) != (sp & PAGE_MASK)) |
| 562 | force_user_fault(sp + 0x38, 0); |
| 563 | force_user_fault(sp, 0); |
David S. Miller | 9088333 | 2010-09-23 22:06:47 -0700 | [diff] [blame] | 564 | |
| 565 | check_stack_aligned(sp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 566 | } |
| 567 | |
| 568 | void window_ret_fault(struct pt_regs *regs) |
| 569 | { |
| 570 | unsigned long sp; |
| 571 | |
| 572 | sp = regs->u_regs[UREG_FP]; |
| 573 | if(((sp + 0x38) & PAGE_MASK) != (sp & PAGE_MASK)) |
| 574 | force_user_fault(sp + 0x38, 0); |
| 575 | force_user_fault(sp, 0); |
David S. Miller | 9088333 | 2010-09-23 22:06:47 -0700 | [diff] [blame] | 576 | |
| 577 | check_stack_aligned(sp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 578 | } |