Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...
[linux-2.6] / arch / um / kernel / tlb.c
1 /*
2  * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
3  * Licensed under the GPL
4  */
5
6 #include <linux/mm.h>
7 #include <linux/sched.h>
8 #include <asm/pgtable.h>
9 #include <asm/tlbflush.h>
10 #include "as-layout.h"
11 #include "mem_user.h"
12 #include "os.h"
13 #include "skas.h"
14 #include "tlb.h"
15
16 struct host_vm_change {
17         struct host_vm_op {
18                 enum { NONE, MMAP, MUNMAP, MPROTECT } type;
19                 union {
20                         struct {
21                                 unsigned long addr;
22                                 unsigned long len;
23                                 unsigned int prot;
24                                 int fd;
25                                 __u64 offset;
26                         } mmap;
27                         struct {
28                                 unsigned long addr;
29                                 unsigned long len;
30                         } munmap;
31                         struct {
32                                 unsigned long addr;
33                                 unsigned long len;
34                                 unsigned int prot;
35                         } mprotect;
36                 } u;
37         } ops[1];
38         int index;
39         struct mm_id *id;
40         void *data;
41         int force;
42 };
43
44 #define INIT_HVC(mm, force) \
45         ((struct host_vm_change) \
46          { .ops         = { { .type = NONE } }, \
47            .id          = &mm->context.id, \
48            .data        = NULL, \
49            .index       = 0, \
50            .force       = force })
51
52 static int do_ops(struct host_vm_change *hvc, int end,
53                   int finished)
54 {
55         struct host_vm_op *op;
56         int i, ret = 0;
57
58         for (i = 0; i < end && !ret; i++) {
59                 op = &hvc->ops[i];
60                 switch (op->type) {
61                 case MMAP:
62                         ret = map(hvc->id, op->u.mmap.addr, op->u.mmap.len,
63                                   op->u.mmap.prot, op->u.mmap.fd,
64                                   op->u.mmap.offset, finished, &hvc->data);
65                         break;
66                 case MUNMAP:
67                         ret = unmap(hvc->id, op->u.munmap.addr,
68                                     op->u.munmap.len, finished, &hvc->data);
69                         break;
70                 case MPROTECT:
71                         ret = protect(hvc->id, op->u.mprotect.addr,
72                                       op->u.mprotect.len, op->u.mprotect.prot,
73                                       finished, &hvc->data);
74                         break;
75                 default:
76                         printk(KERN_ERR "Unknown op type %d in do_ops\n",
77                                op->type);
78                         break;
79                 }
80         }
81
82         return ret;
83 }
84
85 static int add_mmap(unsigned long virt, unsigned long phys, unsigned long len,
86                     unsigned int prot, struct host_vm_change *hvc)
87 {
88         __u64 offset;
89         struct host_vm_op *last;
90         int fd, ret = 0;
91
92         fd = phys_mapping(phys, &offset);
93         if (hvc->index != 0) {
94                 last = &hvc->ops[hvc->index - 1];
95                 if ((last->type == MMAP) &&
96                    (last->u.mmap.addr + last->u.mmap.len == virt) &&
97                    (last->u.mmap.prot == prot) && (last->u.mmap.fd == fd) &&
98                    (last->u.mmap.offset + last->u.mmap.len == offset)) {
99                         last->u.mmap.len += len;
100                         return 0;
101                 }
102         }
103
104         if (hvc->index == ARRAY_SIZE(hvc->ops)) {
105                 ret = do_ops(hvc, ARRAY_SIZE(hvc->ops), 0);
106                 hvc->index = 0;
107         }
108
109         hvc->ops[hvc->index++] = ((struct host_vm_op)
110                                   { .type       = MMAP,
111                                     .u = { .mmap = { .addr      = virt,
112                                                      .len       = len,
113                                                      .prot      = prot,
114                                                      .fd        = fd,
115                                                      .offset    = offset }
116                            } });
117         return ret;
118 }
119
120 static int add_munmap(unsigned long addr, unsigned long len,
121                       struct host_vm_change *hvc)
122 {
123         struct host_vm_op *last;
124         int ret = 0;
125
126         if (hvc->index != 0) {
127                 last = &hvc->ops[hvc->index - 1];
128                 if ((last->type == MUNMAP) &&
129                    (last->u.munmap.addr + last->u.mmap.len == addr)) {
130                         last->u.munmap.len += len;
131                         return 0;
132                 }
133         }
134
135         if (hvc->index == ARRAY_SIZE(hvc->ops)) {
136                 ret = do_ops(hvc, ARRAY_SIZE(hvc->ops), 0);
137                 hvc->index = 0;
138         }
139
140         hvc->ops[hvc->index++] = ((struct host_vm_op)
141                                   { .type       = MUNMAP,
142                                     .u = { .munmap = { .addr    = addr,
143                                                        .len     = len } } });
144         return ret;
145 }
146
147 static int add_mprotect(unsigned long addr, unsigned long len,
148                         unsigned int prot, struct host_vm_change *hvc)
149 {
150         struct host_vm_op *last;
151         int ret = 0;
152
153         if (hvc->index != 0) {
154                 last = &hvc->ops[hvc->index - 1];
155                 if ((last->type == MPROTECT) &&
156                    (last->u.mprotect.addr + last->u.mprotect.len == addr) &&
157                    (last->u.mprotect.prot == prot)) {
158                         last->u.mprotect.len += len;
159                         return 0;
160                 }
161         }
162
163         if (hvc->index == ARRAY_SIZE(hvc->ops)) {
164                 ret = do_ops(hvc, ARRAY_SIZE(hvc->ops), 0);
165                 hvc->index = 0;
166         }
167
168         hvc->ops[hvc->index++] = ((struct host_vm_op)
169                                   { .type       = MPROTECT,
170                                     .u = { .mprotect = { .addr  = addr,
171                                                          .len   = len,
172                                                          .prot  = prot } } });
173         return ret;
174 }
175
176 #define ADD_ROUND(n, inc) (((n) + (inc)) & ~((inc) - 1))
177
178 static inline int update_pte_range(pmd_t *pmd, unsigned long addr,
179                                    unsigned long end,
180                                    struct host_vm_change *hvc)
181 {
182         pte_t *pte;
183         int r, w, x, prot, ret = 0;
184
185         pte = pte_offset_kernel(pmd, addr);
186         do {
187                 if ((addr >= STUB_START) && (addr < STUB_END))
188                         continue;
189
190                 r = pte_read(*pte);
191                 w = pte_write(*pte);
192                 x = pte_exec(*pte);
193                 if (!pte_young(*pte)) {
194                         r = 0;
195                         w = 0;
196                 } else if (!pte_dirty(*pte))
197                         w = 0;
198
199                 prot = ((r ? UM_PROT_READ : 0) | (w ? UM_PROT_WRITE : 0) |
200                         (x ? UM_PROT_EXEC : 0));
201                 if (hvc->force || pte_newpage(*pte)) {
202                         if (pte_present(*pte))
203                                 ret = add_mmap(addr, pte_val(*pte) & PAGE_MASK,
204                                                PAGE_SIZE, prot, hvc);
205                         else
206                                 ret = add_munmap(addr, PAGE_SIZE, hvc);
207                 } else if (pte_newprot(*pte))
208                         ret = add_mprotect(addr, PAGE_SIZE, prot, hvc);
209                 *pte = pte_mkuptodate(*pte);
210         } while (pte++, addr += PAGE_SIZE, ((addr < end) && !ret));
211         return ret;
212 }
213
214 static inline int update_pmd_range(pud_t *pud, unsigned long addr,
215                                    unsigned long end,
216                                    struct host_vm_change *hvc)
217 {
218         pmd_t *pmd;
219         unsigned long next;
220         int ret = 0;
221
222         pmd = pmd_offset(pud, addr);
223         do {
224                 next = pmd_addr_end(addr, end);
225                 if (!pmd_present(*pmd)) {
226                         if (hvc->force || pmd_newpage(*pmd)) {
227                                 ret = add_munmap(addr, next - addr, hvc);
228                                 pmd_mkuptodate(*pmd);
229                         }
230                 }
231                 else ret = update_pte_range(pmd, addr, next, hvc);
232         } while (pmd++, addr = next, ((addr < end) && !ret));
233         return ret;
234 }
235
236 static inline int update_pud_range(pgd_t *pgd, unsigned long addr,
237                                    unsigned long end,
238                                    struct host_vm_change *hvc)
239 {
240         pud_t *pud;
241         unsigned long next;
242         int ret = 0;
243
244         pud = pud_offset(pgd, addr);
245         do {
246                 next = pud_addr_end(addr, end);
247                 if (!pud_present(*pud)) {
248                         if (hvc->force || pud_newpage(*pud)) {
249                                 ret = add_munmap(addr, next - addr, hvc);
250                                 pud_mkuptodate(*pud);
251                         }
252                 }
253                 else ret = update_pmd_range(pud, addr, next, hvc);
254         } while (pud++, addr = next, ((addr < end) && !ret));
255         return ret;
256 }
257
258 void fix_range_common(struct mm_struct *mm, unsigned long start_addr,
259                       unsigned long end_addr, int force)
260 {
261         pgd_t *pgd;
262         struct host_vm_change hvc;
263         unsigned long addr = start_addr, next;
264         int ret = 0;
265
266         hvc = INIT_HVC(mm, force);
267         pgd = pgd_offset(mm, addr);
268         do {
269                 next = pgd_addr_end(addr, end_addr);
270                 if (!pgd_present(*pgd)) {
271                         if (force || pgd_newpage(*pgd)) {
272                                 ret = add_munmap(addr, next - addr, &hvc);
273                                 pgd_mkuptodate(*pgd);
274                         }
275                 }
276                 else ret = update_pud_range(pgd, addr, next, &hvc);
277         } while (pgd++, addr = next, ((addr < end_addr) && !ret));
278
279         if (!ret)
280                 ret = do_ops(&hvc, hvc.index, 1);
281
282         /* This is not an else because ret is modified above */
283         if (ret) {
284                 printk(KERN_ERR "fix_range_common: failed, killing current "
285                        "process\n");
286                 force_sig(SIGKILL, current);
287         }
288 }
289
290 int flush_tlb_kernel_range_common(unsigned long start, unsigned long end)
291 {
292         struct mm_struct *mm;
293         pgd_t *pgd;
294         pud_t *pud;
295         pmd_t *pmd;
296         pte_t *pte;
297         unsigned long addr, last;
298         int updated = 0, err;
299
300         mm = &init_mm;
301         for (addr = start; addr < end;) {
302                 pgd = pgd_offset(mm, addr);
303                 if (!pgd_present(*pgd)) {
304                         last = ADD_ROUND(addr, PGDIR_SIZE);
305                         if (last > end)
306                                 last = end;
307                         if (pgd_newpage(*pgd)) {
308                                 updated = 1;
309                                 err = os_unmap_memory((void *) addr,
310                                                       last - addr);
311                                 if (err < 0)
312                                         panic("munmap failed, errno = %d\n",
313                                               -err);
314                         }
315                         addr = last;
316                         continue;
317                 }
318
319                 pud = pud_offset(pgd, addr);
320                 if (!pud_present(*pud)) {
321                         last = ADD_ROUND(addr, PUD_SIZE);
322                         if (last > end)
323                                 last = end;
324                         if (pud_newpage(*pud)) {
325                                 updated = 1;
326                                 err = os_unmap_memory((void *) addr,
327                                                       last - addr);
328                                 if (err < 0)
329                                         panic("munmap failed, errno = %d\n",
330                                               -err);
331                         }
332                         addr = last;
333                         continue;
334                 }
335
336                 pmd = pmd_offset(pud, addr);
337                 if (!pmd_present(*pmd)) {
338                         last = ADD_ROUND(addr, PMD_SIZE);
339                         if (last > end)
340                                 last = end;
341                         if (pmd_newpage(*pmd)) {
342                                 updated = 1;
343                                 err = os_unmap_memory((void *) addr,
344                                                       last - addr);
345                                 if (err < 0)
346                                         panic("munmap failed, errno = %d\n",
347                                               -err);
348                         }
349                         addr = last;
350                         continue;
351                 }
352
353                 pte = pte_offset_kernel(pmd, addr);
354                 if (!pte_present(*pte) || pte_newpage(*pte)) {
355                         updated = 1;
356                         err = os_unmap_memory((void *) addr,
357                                               PAGE_SIZE);
358                         if (err < 0)
359                                 panic("munmap failed, errno = %d\n",
360                                       -err);
361                         if (pte_present(*pte))
362                                 map_memory(addr,
363                                            pte_val(*pte) & PAGE_MASK,
364                                            PAGE_SIZE, 1, 1, 1);
365                 }
366                 else if (pte_newprot(*pte)) {
367                         updated = 1;
368                         os_protect_memory((void *) addr, PAGE_SIZE, 1, 1, 1);
369                 }
370                 addr += PAGE_SIZE;
371         }
372         return updated;
373 }
374
375 void flush_tlb_page(struct vm_area_struct *vma, unsigned long address)
376 {
377         pgd_t *pgd;
378         pud_t *pud;
379         pmd_t *pmd;
380         pte_t *pte;
381         struct mm_struct *mm = vma->vm_mm;
382         void *flush = NULL;
383         int r, w, x, prot, err = 0;
384         struct mm_id *mm_id;
385
386         address &= PAGE_MASK;
387         pgd = pgd_offset(mm, address);
388         if (!pgd_present(*pgd))
389                 goto kill;
390
391         pud = pud_offset(pgd, address);
392         if (!pud_present(*pud))
393                 goto kill;
394
395         pmd = pmd_offset(pud, address);
396         if (!pmd_present(*pmd))
397                 goto kill;
398
399         pte = pte_offset_kernel(pmd, address);
400
401         r = pte_read(*pte);
402         w = pte_write(*pte);
403         x = pte_exec(*pte);
404         if (!pte_young(*pte)) {
405                 r = 0;
406                 w = 0;
407         } else if (!pte_dirty(*pte)) {
408                 w = 0;
409         }
410
411         mm_id = &mm->context.id;
412         prot = ((r ? UM_PROT_READ : 0) | (w ? UM_PROT_WRITE : 0) |
413                 (x ? UM_PROT_EXEC : 0));
414         if (pte_newpage(*pte)) {
415                 if (pte_present(*pte)) {
416                         unsigned long long offset;
417                         int fd;
418
419                         fd = phys_mapping(pte_val(*pte) & PAGE_MASK, &offset);
420                         err = map(mm_id, address, PAGE_SIZE, prot, fd, offset,
421                                   1, &flush);
422                 }
423                 else err = unmap(mm_id, address, PAGE_SIZE, 1, &flush);
424         }
425         else if (pte_newprot(*pte))
426                 err = protect(mm_id, address, PAGE_SIZE, prot, 1, &flush);
427
428         if (err)
429                 goto kill;
430
431         *pte = pte_mkuptodate(*pte);
432
433         return;
434
435 kill:
436         printk(KERN_ERR "Failed to flush page for address 0x%lx\n", address);
437         force_sig(SIGKILL, current);
438 }
439
440 pgd_t *pgd_offset_proc(struct mm_struct *mm, unsigned long address)
441 {
442         return pgd_offset(mm, address);
443 }
444
445 pud_t *pud_offset_proc(pgd_t *pgd, unsigned long address)
446 {
447         return pud_offset(pgd, address);
448 }
449
450 pmd_t *pmd_offset_proc(pud_t *pud, unsigned long address)
451 {
452         return pmd_offset(pud, address);
453 }
454
455 pte_t *pte_offset_proc(pmd_t *pmd, unsigned long address)
456 {
457         return pte_offset_kernel(pmd, address);
458 }
459
460 pte_t *addr_pte(struct task_struct *task, unsigned long addr)
461 {
462         pgd_t *pgd = pgd_offset(task->mm, addr);
463         pud_t *pud = pud_offset(pgd, addr);
464         pmd_t *pmd = pmd_offset(pud, addr);
465
466         return pte_offset_map(pmd, addr);
467 }
468
469 void flush_tlb_all(void)
470 {
471         flush_tlb_mm(current->mm);
472 }
473
474 void flush_tlb_kernel_range(unsigned long start, unsigned long end)
475 {
476         flush_tlb_kernel_range_common(start, end);
477 }
478
479 void flush_tlb_kernel_vm(void)
480 {
481         flush_tlb_kernel_range_common(start_vm, end_vm);
482 }
483
484 void __flush_tlb_one(unsigned long addr)
485 {
486         flush_tlb_kernel_range_common(addr, addr + PAGE_SIZE);
487 }
488
489 static void fix_range(struct mm_struct *mm, unsigned long start_addr,
490                       unsigned long end_addr, int force)
491 {
492         fix_range_common(mm, start_addr, end_addr, force);
493 }
494
495 void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
496                      unsigned long end)
497 {
498         if (vma->vm_mm == NULL)
499                 flush_tlb_kernel_range_common(start, end);
500         else fix_range(vma->vm_mm, start, end, 0);
501 }
502
503 void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start,
504                         unsigned long end)
505 {
506         /*
507          * Don't bother flushing if this address space is about to be
508          * destroyed.
509          */
510         if (atomic_read(&mm->mm_users) == 0)
511                 return;
512
513         fix_range(mm, start, end, 0);
514 }
515
516 void flush_tlb_mm(struct mm_struct *mm)
517 {
518         struct vm_area_struct *vma = mm->mmap;
519
520         while (vma != NULL) {
521                 fix_range(mm, vma->vm_start, vma->vm_end, 0);
522                 vma = vma->vm_next;
523         }
524 }
525
526 void force_flush_all(void)
527 {
528         struct mm_struct *mm = current->mm;
529         struct vm_area_struct *vma = mm->mmap;
530
531         while (vma != NULL) {
532                 fix_range(mm, vma->vm_start, vma->vm_end, 1);
533                 vma = vma->vm_next;
534         }
535 }