diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/sh/mm/fault.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'arch/sh/mm/fault.c')
-rw-r--r-- | arch/sh/mm/fault.c | 374 |
1 files changed, 374 insertions, 0 deletions
diff --git a/arch/sh/mm/fault.c b/arch/sh/mm/fault.c new file mode 100644 index 000000000000..7abba2161da6 --- /dev/null +++ b/arch/sh/mm/fault.c | |||
@@ -0,0 +1,374 @@ | |||
1 | /* $Id: fault.c,v 1.14 2004/01/13 05:52:11 kkojima Exp $ | ||
2 | * | ||
3 | * linux/arch/sh/mm/fault.c | ||
4 | * Copyright (C) 1999 Niibe Yutaka | ||
5 | * Copyright (C) 2003 Paul Mundt | ||
6 | * | ||
7 | * Based on linux/arch/i386/mm/fault.c: | ||
8 | * Copyright (C) 1995 Linus Torvalds | ||
9 | */ | ||
10 | |||
11 | #include <linux/signal.h> | ||
12 | #include <linux/sched.h> | ||
13 | #include <linux/kernel.h> | ||
14 | #include <linux/errno.h> | ||
15 | #include <linux/string.h> | ||
16 | #include <linux/types.h> | ||
17 | #include <linux/ptrace.h> | ||
18 | #include <linux/mman.h> | ||
19 | #include <linux/mm.h> | ||
20 | #include <linux/smp.h> | ||
21 | #include <linux/smp_lock.h> | ||
22 | #include <linux/interrupt.h> | ||
23 | #include <linux/module.h> | ||
24 | |||
25 | #include <asm/system.h> | ||
26 | #include <asm/io.h> | ||
27 | #include <asm/uaccess.h> | ||
28 | #include <asm/pgalloc.h> | ||
29 | #include <asm/mmu_context.h> | ||
30 | #include <asm/cacheflush.h> | ||
31 | #include <asm/kgdb.h> | ||
32 | |||
33 | extern void die(const char *,struct pt_regs *,long); | ||
34 | |||
35 | /* | ||
36 | * This routine handles page faults. It determines the address, | ||
37 | * and the problem, and then passes it off to one of the appropriate | ||
38 | * routines. | ||
39 | */ | ||
40 | asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long writeaccess, | ||
41 | unsigned long address) | ||
42 | { | ||
43 | struct task_struct *tsk; | ||
44 | struct mm_struct *mm; | ||
45 | struct vm_area_struct * vma; | ||
46 | unsigned long page; | ||
47 | |||
48 | #ifdef CONFIG_SH_KGDB | ||
49 | if (kgdb_nofault && kgdb_bus_err_hook) | ||
50 | kgdb_bus_err_hook(); | ||
51 | #endif | ||
52 | |||
53 | tsk = current; | ||
54 | mm = tsk->mm; | ||
55 | |||
56 | /* | ||
57 | * If we're in an interrupt or have no user | ||
58 | * context, we must not take the fault.. | ||
59 | */ | ||
60 | if (in_atomic() || !mm) | ||
61 | goto no_context; | ||
62 | |||
63 | down_read(&mm->mmap_sem); | ||
64 | |||
65 | vma = find_vma(mm, address); | ||
66 | if (!vma) | ||
67 | goto bad_area; | ||
68 | if (vma->vm_start <= address) | ||
69 | goto good_area; | ||
70 | if (!(vma->vm_flags & VM_GROWSDOWN)) | ||
71 | goto bad_area; | ||
72 | if (expand_stack(vma, address)) | ||
73 | goto bad_area; | ||
74 | /* | ||
75 | * Ok, we have a good vm_area for this memory access, so | ||
76 | * we can handle it.. | ||
77 | */ | ||
78 | good_area: | ||
79 | if (writeaccess) { | ||
80 | if (!(vma->vm_flags & VM_WRITE)) | ||
81 | goto bad_area; | ||
82 | } else { | ||
83 | if (!(vma->vm_flags & (VM_READ | VM_EXEC))) | ||
84 | goto bad_area; | ||
85 | } | ||
86 | |||
87 | /* | ||
88 | * If for any reason at all we couldn't handle the fault, | ||
89 | * make sure we exit gracefully rather than endlessly redo | ||
90 | * the fault. | ||
91 | */ | ||
92 | survive: | ||
93 | switch (handle_mm_fault(mm, vma, address, writeaccess)) { | ||
94 | case VM_FAULT_MINOR: | ||
95 | tsk->min_flt++; | ||
96 | break; | ||
97 | case VM_FAULT_MAJOR: | ||
98 | tsk->maj_flt++; | ||
99 | break; | ||
100 | case VM_FAULT_SIGBUS: | ||
101 | goto do_sigbus; | ||
102 | case VM_FAULT_OOM: | ||
103 | goto out_of_memory; | ||
104 | default: | ||
105 | BUG(); | ||
106 | } | ||
107 | |||
108 | up_read(&mm->mmap_sem); | ||
109 | return; | ||
110 | |||
111 | /* | ||
112 | * Something tried to access memory that isn't in our memory map.. | ||
113 | * Fix it, but check if it's kernel or user first.. | ||
114 | */ | ||
115 | bad_area: | ||
116 | up_read(&mm->mmap_sem); | ||
117 | |||
118 | if (user_mode(regs)) { | ||
119 | tsk->thread.address = address; | ||
120 | tsk->thread.error_code = writeaccess; | ||
121 | force_sig(SIGSEGV, tsk); | ||
122 | return; | ||
123 | } | ||
124 | |||
125 | no_context: | ||
126 | /* Are we prepared to handle this kernel fault? */ | ||
127 | if (fixup_exception(regs)) | ||
128 | return; | ||
129 | |||
130 | /* | ||
131 | * Oops. The kernel tried to access some bad page. We'll have to | ||
132 | * terminate things with extreme prejudice. | ||
133 | * | ||
134 | */ | ||
135 | if (address < PAGE_SIZE) | ||
136 | printk(KERN_ALERT "Unable to handle kernel NULL pointer dereference"); | ||
137 | else | ||
138 | printk(KERN_ALERT "Unable to handle kernel paging request"); | ||
139 | printk(" at virtual address %08lx\n", address); | ||
140 | printk(KERN_ALERT "pc = %08lx\n", regs->pc); | ||
141 | asm volatile("mov.l %1, %0" | ||
142 | : "=r" (page) | ||
143 | : "m" (__m(MMU_TTB))); | ||
144 | if (page) { | ||
145 | page = ((unsigned long *) page)[address >> 22]; | ||
146 | printk(KERN_ALERT "*pde = %08lx\n", page); | ||
147 | if (page & _PAGE_PRESENT) { | ||
148 | page &= PAGE_MASK; | ||
149 | address &= 0x003ff000; | ||
150 | page = ((unsigned long *) __va(page))[address >> PAGE_SHIFT]; | ||
151 | printk(KERN_ALERT "*pte = %08lx\n", page); | ||
152 | } | ||
153 | } | ||
154 | die("Oops", regs, writeaccess); | ||
155 | do_exit(SIGKILL); | ||
156 | |||
157 | /* | ||
158 | * We ran out of memory, or some other thing happened to us that made | ||
159 | * us unable to handle the page fault gracefully. | ||
160 | */ | ||
161 | out_of_memory: | ||
162 | up_read(&mm->mmap_sem); | ||
163 | if (current->pid == 1) { | ||
164 | yield(); | ||
165 | down_read(&mm->mmap_sem); | ||
166 | goto survive; | ||
167 | } | ||
168 | printk("VM: killing process %s\n", tsk->comm); | ||
169 | if (user_mode(regs)) | ||
170 | do_exit(SIGKILL); | ||
171 | goto no_context; | ||
172 | |||
173 | do_sigbus: | ||
174 | up_read(&mm->mmap_sem); | ||
175 | |||
176 | /* | ||
177 | * Send a sigbus, regardless of whether we were in kernel | ||
178 | * or user mode. | ||
179 | */ | ||
180 | tsk->thread.address = address; | ||
181 | tsk->thread.error_code = writeaccess; | ||
182 | tsk->thread.trap_no = 14; | ||
183 | force_sig(SIGBUS, tsk); | ||
184 | |||
185 | /* Kernel mode? Handle exceptions or die */ | ||
186 | if (!user_mode(regs)) | ||
187 | goto no_context; | ||
188 | } | ||
189 | |||
190 | /* | ||
191 | * Called with interrupt disabled. | ||
192 | */ | ||
193 | asmlinkage int __do_page_fault(struct pt_regs *regs, unsigned long writeaccess, | ||
194 | unsigned long address) | ||
195 | { | ||
196 | unsigned long addrmax = P4SEG; | ||
197 | pgd_t *dir; | ||
198 | pmd_t *pmd; | ||
199 | pte_t *pte; | ||
200 | pte_t entry; | ||
201 | |||
202 | #ifdef CONFIG_SH_KGDB | ||
203 | if (kgdb_nofault && kgdb_bus_err_hook) | ||
204 | kgdb_bus_err_hook(); | ||
205 | #endif | ||
206 | |||
207 | #ifdef CONFIG_SH_STORE_QUEUES | ||
208 | addrmax = P4SEG_STORE_QUE + 0x04000000; | ||
209 | #endif | ||
210 | |||
211 | if (address >= P3SEG && address < addrmax) | ||
212 | dir = pgd_offset_k(address); | ||
213 | else if (address >= TASK_SIZE) | ||
214 | return 1; | ||
215 | else if (!current->mm) | ||
216 | return 1; | ||
217 | else | ||
218 | dir = pgd_offset(current->mm, address); | ||
219 | |||
220 | pmd = pmd_offset(dir, address); | ||
221 | if (pmd_none(*pmd)) | ||
222 | return 1; | ||
223 | if (pmd_bad(*pmd)) { | ||
224 | pmd_ERROR(*pmd); | ||
225 | pmd_clear(pmd); | ||
226 | return 1; | ||
227 | } | ||
228 | pte = pte_offset_kernel(pmd, address); | ||
229 | entry = *pte; | ||
230 | if (pte_none(entry) || pte_not_present(entry) | ||
231 | || (writeaccess && !pte_write(entry))) | ||
232 | return 1; | ||
233 | |||
234 | if (writeaccess) | ||
235 | entry = pte_mkdirty(entry); | ||
236 | entry = pte_mkyoung(entry); | ||
237 | |||
238 | #ifdef CONFIG_CPU_SH4 | ||
239 | /* | ||
240 | * ITLB is not affected by "ldtlb" instruction. | ||
241 | * So, we need to flush the entry by ourselves. | ||
242 | */ | ||
243 | |||
244 | { | ||
245 | unsigned long flags; | ||
246 | local_irq_save(flags); | ||
247 | __flush_tlb_page(get_asid(), address&PAGE_MASK); | ||
248 | local_irq_restore(flags); | ||
249 | } | ||
250 | #endif | ||
251 | |||
252 | set_pte(pte, entry); | ||
253 | update_mmu_cache(NULL, address, entry); | ||
254 | |||
255 | return 0; | ||
256 | } | ||
257 | |||
258 | void flush_tlb_page(struct vm_area_struct *vma, unsigned long page) | ||
259 | { | ||
260 | if (vma->vm_mm && vma->vm_mm->context != NO_CONTEXT) { | ||
261 | unsigned long flags; | ||
262 | unsigned long asid; | ||
263 | unsigned long saved_asid = MMU_NO_ASID; | ||
264 | |||
265 | asid = vma->vm_mm->context & MMU_CONTEXT_ASID_MASK; | ||
266 | page &= PAGE_MASK; | ||
267 | |||
268 | local_irq_save(flags); | ||
269 | if (vma->vm_mm != current->mm) { | ||
270 | saved_asid = get_asid(); | ||
271 | set_asid(asid); | ||
272 | } | ||
273 | __flush_tlb_page(asid, page); | ||
274 | if (saved_asid != MMU_NO_ASID) | ||
275 | set_asid(saved_asid); | ||
276 | local_irq_restore(flags); | ||
277 | } | ||
278 | } | ||
279 | |||
280 | void flush_tlb_range(struct vm_area_struct *vma, unsigned long start, | ||
281 | unsigned long end) | ||
282 | { | ||
283 | struct mm_struct *mm = vma->vm_mm; | ||
284 | |||
285 | if (mm->context != NO_CONTEXT) { | ||
286 | unsigned long flags; | ||
287 | int size; | ||
288 | |||
289 | local_irq_save(flags); | ||
290 | size = (end - start + (PAGE_SIZE - 1)) >> PAGE_SHIFT; | ||
291 | if (size > (MMU_NTLB_ENTRIES/4)) { /* Too many TLB to flush */ | ||
292 | mm->context = NO_CONTEXT; | ||
293 | if (mm == current->mm) | ||
294 | activate_context(mm); | ||
295 | } else { | ||
296 | unsigned long asid = mm->context&MMU_CONTEXT_ASID_MASK; | ||
297 | unsigned long saved_asid = MMU_NO_ASID; | ||
298 | |||
299 | start &= PAGE_MASK; | ||
300 | end += (PAGE_SIZE - 1); | ||
301 | end &= PAGE_MASK; | ||
302 | if (mm != current->mm) { | ||
303 | saved_asid = get_asid(); | ||
304 | set_asid(asid); | ||
305 | } | ||
306 | while (start < end) { | ||
307 | __flush_tlb_page(asid, start); | ||
308 | start += PAGE_SIZE; | ||
309 | } | ||
310 | if (saved_asid != MMU_NO_ASID) | ||
311 | set_asid(saved_asid); | ||
312 | } | ||
313 | local_irq_restore(flags); | ||
314 | } | ||
315 | } | ||
316 | |||
317 | void flush_tlb_kernel_range(unsigned long start, unsigned long end) | ||
318 | { | ||
319 | unsigned long flags; | ||
320 | int size; | ||
321 | |||
322 | local_irq_save(flags); | ||
323 | size = (end - start + (PAGE_SIZE - 1)) >> PAGE_SHIFT; | ||
324 | if (size > (MMU_NTLB_ENTRIES/4)) { /* Too many TLB to flush */ | ||
325 | flush_tlb_all(); | ||
326 | } else { | ||
327 | unsigned long asid = init_mm.context&MMU_CONTEXT_ASID_MASK; | ||
328 | unsigned long saved_asid = get_asid(); | ||
329 | |||
330 | start &= PAGE_MASK; | ||
331 | end += (PAGE_SIZE - 1); | ||
332 | end &= PAGE_MASK; | ||
333 | set_asid(asid); | ||
334 | while (start < end) { | ||
335 | __flush_tlb_page(asid, start); | ||
336 | start += PAGE_SIZE; | ||
337 | } | ||
338 | set_asid(saved_asid); | ||
339 | } | ||
340 | local_irq_restore(flags); | ||
341 | } | ||
342 | |||
343 | void flush_tlb_mm(struct mm_struct *mm) | ||
344 | { | ||
345 | /* Invalidate all TLB of this process. */ | ||
346 | /* Instead of invalidating each TLB, we get new MMU context. */ | ||
347 | if (mm->context != NO_CONTEXT) { | ||
348 | unsigned long flags; | ||
349 | |||
350 | local_irq_save(flags); | ||
351 | mm->context = NO_CONTEXT; | ||
352 | if (mm == current->mm) | ||
353 | activate_context(mm); | ||
354 | local_irq_restore(flags); | ||
355 | } | ||
356 | } | ||
357 | |||
358 | void flush_tlb_all(void) | ||
359 | { | ||
360 | unsigned long flags, status; | ||
361 | |||
362 | /* | ||
363 | * Flush all the TLB. | ||
364 | * | ||
365 | * Write to the MMU control register's bit: | ||
366 | * TF-bit for SH-3, TI-bit for SH-4. | ||
367 | * It's same position, bit #2. | ||
368 | */ | ||
369 | local_irq_save(flags); | ||
370 | status = ctrl_inl(MMUCR); | ||
371 | status |= 0x04; | ||
372 | ctrl_outl(status, MMUCR); | ||
373 | local_irq_restore(flags); | ||
374 | } | ||