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6#include <linux/mm.h>
7#include <linux/module.h>
8#include <linux/sched/signal.h>
9
10#include <asm/tlbflush.h>
11#include <as-layout.h>
12#include <mem_user.h>
13#include <os.h>
14#include <skas.h>
15#include <kern_util.h>
16
17struct host_vm_change {
18 struct host_vm_op {
19 enum { NONE, MMAP, MUNMAP, MPROTECT } type;
20 union {
21 struct {
22 unsigned long addr;
23 unsigned long len;
24 unsigned int prot;
25 int fd;
26 __u64 offset;
27 } mmap;
28 struct {
29 unsigned long addr;
30 unsigned long len;
31 } munmap;
32 struct {
33 unsigned long addr;
34 unsigned long len;
35 unsigned int prot;
36 } mprotect;
37 } u;
38 } ops[1];
39 int userspace;
40 int index;
41 struct mm_struct *mm;
42 void *data;
43 int force;
44};
45
46#define INIT_HVC(mm, force, userspace) \
47 ((struct host_vm_change) \
48 { .ops = { { .type = NONE } }, \
49 .mm = mm, \
50 .data = NULL, \
51 .userspace = userspace, \
52 .index = 0, \
53 .force = force })
54
55static void report_enomem(void)
56{
57 printk(KERN_ERR "UML ran out of memory on the host side! "
58 "This can happen due to a memory limitation or "
59 "vm.max_map_count has been reached.\n");
60}
61
62static int do_ops(struct host_vm_change *hvc, int end,
63 int finished)
64{
65 struct host_vm_op *op;
66 int i, ret = 0;
67
68 for (i = 0; i < end && !ret; i++) {
69 op = &hvc->ops[i];
70 switch (op->type) {
71 case MMAP:
72 if (hvc->userspace)
73 ret = map(&hvc->mm->context.id, op->u.mmap.addr,
74 op->u.mmap.len, op->u.mmap.prot,
75 op->u.mmap.fd,
76 op->u.mmap.offset, finished,
77 &hvc->data);
78 else
79 map_memory(op->u.mmap.addr, op->u.mmap.offset,
80 op->u.mmap.len, 1, 1, 1);
81 break;
82 case MUNMAP:
83 if (hvc->userspace)
84 ret = unmap(&hvc->mm->context.id,
85 op->u.munmap.addr,
86 op->u.munmap.len, finished,
87 &hvc->data);
88 else
89 ret = os_unmap_memory(
90 (void *) op->u.munmap.addr,
91 op->u.munmap.len);
92
93 break;
94 case MPROTECT:
95 if (hvc->userspace)
96 ret = protect(&hvc->mm->context.id,
97 op->u.mprotect.addr,
98 op->u.mprotect.len,
99 op->u.mprotect.prot,
100 finished, &hvc->data);
101 else
102 ret = os_protect_memory(
103 (void *) op->u.mprotect.addr,
104 op->u.mprotect.len,
105 1, 1, 1);
106 break;
107 default:
108 printk(KERN_ERR "Unknown op type %d in do_ops\n",
109 op->type);
110 BUG();
111 break;
112 }
113 }
114
115 if (ret == -ENOMEM)
116 report_enomem();
117
118 return ret;
119}
120
121static int add_mmap(unsigned long virt, unsigned long phys, unsigned long len,
122 unsigned int prot, struct host_vm_change *hvc)
123{
124 __u64 offset;
125 struct host_vm_op *last;
126 int fd = -1, ret = 0;
127
128 if (hvc->userspace)
129 fd = phys_mapping(phys, &offset);
130 else
131 offset = phys;
132 if (hvc->index != 0) {
133 last = &hvc->ops[hvc->index - 1];
134 if ((last->type == MMAP) &&
135 (last->u.mmap.addr + last->u.mmap.len == virt) &&
136 (last->u.mmap.prot == prot) && (last->u.mmap.fd == fd) &&
137 (last->u.mmap.offset + last->u.mmap.len == offset)) {
138 last->u.mmap.len += len;
139 return 0;
140 }
141 }
142
143 if (hvc->index == ARRAY_SIZE(hvc->ops)) {
144 ret = do_ops(hvc, ARRAY_SIZE(hvc->ops), 0);
145 hvc->index = 0;
146 }
147
148 hvc->ops[hvc->index++] = ((struct host_vm_op)
149 { .type = MMAP,
150 .u = { .mmap = { .addr = virt,
151 .len = len,
152 .prot = prot,
153 .fd = fd,
154 .offset = offset }
155 } });
156 return ret;
157}
158
159static int add_munmap(unsigned long addr, unsigned long len,
160 struct host_vm_change *hvc)
161{
162 struct host_vm_op *last;
163 int ret = 0;
164
165 if (hvc->index != 0) {
166 last = &hvc->ops[hvc->index - 1];
167 if ((last->type == MUNMAP) &&
168 (last->u.munmap.addr + last->u.mmap.len == addr)) {
169 last->u.munmap.len += len;
170 return 0;
171 }
172 }
173
174 if (hvc->index == ARRAY_SIZE(hvc->ops)) {
175 ret = do_ops(hvc, ARRAY_SIZE(hvc->ops), 0);
176 hvc->index = 0;
177 }
178
179 hvc->ops[hvc->index++] = ((struct host_vm_op)
180 { .type = MUNMAP,
181 .u = { .munmap = { .addr = addr,
182 .len = len } } });
183 return ret;
184}
185
186static int add_mprotect(unsigned long addr, unsigned long len,
187 unsigned int prot, struct host_vm_change *hvc)
188{
189 struct host_vm_op *last;
190 int ret = 0;
191
192 if (hvc->index != 0) {
193 last = &hvc->ops[hvc->index - 1];
194 if ((last->type == MPROTECT) &&
195 (last->u.mprotect.addr + last->u.mprotect.len == addr) &&
196 (last->u.mprotect.prot == prot)) {
197 last->u.mprotect.len += len;
198 return 0;
199 }
200 }
201
202 if (hvc->index == ARRAY_SIZE(hvc->ops)) {
203 ret = do_ops(hvc, ARRAY_SIZE(hvc->ops), 0);
204 hvc->index = 0;
205 }
206
207 hvc->ops[hvc->index++] = ((struct host_vm_op)
208 { .type = MPROTECT,
209 .u = { .mprotect = { .addr = addr,
210 .len = len,
211 .prot = prot } } });
212 return ret;
213}
214
215#define ADD_ROUND(n, inc) (((n) + (inc)) & ~((inc) - 1))
216
217static inline int update_pte_range(pmd_t *pmd, unsigned long addr,
218 unsigned long end,
219 struct host_vm_change *hvc)
220{
221 pte_t *pte;
222 int r, w, x, prot, ret = 0;
223
224 pte = pte_offset_kernel(pmd, addr);
225 do {
226 r = pte_read(*pte);
227 w = pte_write(*pte);
228 x = pte_exec(*pte);
229 if (!pte_young(*pte)) {
230 r = 0;
231 w = 0;
232 } else if (!pte_dirty(*pte))
233 w = 0;
234
235 prot = ((r ? UM_PROT_READ : 0) | (w ? UM_PROT_WRITE : 0) |
236 (x ? UM_PROT_EXEC : 0));
237 if (hvc->force || pte_newpage(*pte)) {
238 if (pte_present(*pte)) {
239 if (pte_newpage(*pte))
240 ret = add_mmap(addr, pte_val(*pte) & PAGE_MASK,
241 PAGE_SIZE, prot, hvc);
242 } else
243 ret = add_munmap(addr, PAGE_SIZE, hvc);
244 } else if (pte_newprot(*pte))
245 ret = add_mprotect(addr, PAGE_SIZE, prot, hvc);
246 *pte = pte_mkuptodate(*pte);
247 } while (pte++, addr += PAGE_SIZE, ((addr < end) && !ret));
248 return ret;
249}
250
251static inline int update_pmd_range(pud_t *pud, unsigned long addr,
252 unsigned long end,
253 struct host_vm_change *hvc)
254{
255 pmd_t *pmd;
256 unsigned long next;
257 int ret = 0;
258
259 pmd = pmd_offset(pud, addr);
260 do {
261 next = pmd_addr_end(addr, end);
262 if (!pmd_present(*pmd)) {
263 if (hvc->force || pmd_newpage(*pmd)) {
264 ret = add_munmap(addr, next - addr, hvc);
265 pmd_mkuptodate(*pmd);
266 }
267 }
268 else ret = update_pte_range(pmd, addr, next, hvc);
269 } while (pmd++, addr = next, ((addr < end) && !ret));
270 return ret;
271}
272
273static inline int update_pud_range(p4d_t *p4d, unsigned long addr,
274 unsigned long end,
275 struct host_vm_change *hvc)
276{
277 pud_t *pud;
278 unsigned long next;
279 int ret = 0;
280
281 pud = pud_offset(p4d, addr);
282 do {
283 next = pud_addr_end(addr, end);
284 if (!pud_present(*pud)) {
285 if (hvc->force || pud_newpage(*pud)) {
286 ret = add_munmap(addr, next - addr, hvc);
287 pud_mkuptodate(*pud);
288 }
289 }
290 else ret = update_pmd_range(pud, addr, next, hvc);
291 } while (pud++, addr = next, ((addr < end) && !ret));
292 return ret;
293}
294
295static inline int update_p4d_range(pgd_t *pgd, unsigned long addr,
296 unsigned long end,
297 struct host_vm_change *hvc)
298{
299 p4d_t *p4d;
300 unsigned long next;
301 int ret = 0;
302
303 p4d = p4d_offset(pgd, addr);
304 do {
305 next = p4d_addr_end(addr, end);
306 if (!p4d_present(*p4d)) {
307 if (hvc->force || p4d_newpage(*p4d)) {
308 ret = add_munmap(addr, next - addr, hvc);
309 p4d_mkuptodate(*p4d);
310 }
311 } else
312 ret = update_pud_range(p4d, addr, next, hvc);
313 } while (p4d++, addr = next, ((addr < end) && !ret));
314 return ret;
315}
316
317void fix_range_common(struct mm_struct *mm, unsigned long start_addr,
318 unsigned long end_addr, int force)
319{
320 pgd_t *pgd;
321 struct host_vm_change hvc;
322 unsigned long addr = start_addr, next;
323 int ret = 0, userspace = 1;
324
325 hvc = INIT_HVC(mm, force, userspace);
326 pgd = pgd_offset(mm, addr);
327 do {
328 next = pgd_addr_end(addr, end_addr);
329 if (!pgd_present(*pgd)) {
330 if (force || pgd_newpage(*pgd)) {
331 ret = add_munmap(addr, next - addr, &hvc);
332 pgd_mkuptodate(*pgd);
333 }
334 } else
335 ret = update_p4d_range(pgd, addr, next, &hvc);
336 } while (pgd++, addr = next, ((addr < end_addr) && !ret));
337
338 if (!ret)
339 ret = do_ops(&hvc, hvc.index, 1);
340
341
342 if (ret) {
343 struct mm_id *mm_idp = ¤t->mm->context.id;
344
345 printk(KERN_ERR "fix_range_common: failed, killing current "
346 "process: %d\n", task_tgid_vnr(current));
347 mm_idp->kill = 1;
348 }
349}
350
351static int flush_tlb_kernel_range_common(unsigned long start, unsigned long end)
352{
353 struct mm_struct *mm;
354 pgd_t *pgd;
355 p4d_t *p4d;
356 pud_t *pud;
357 pmd_t *pmd;
358 pte_t *pte;
359 unsigned long addr, last;
360 int updated = 0, err = 0, force = 0, userspace = 0;
361 struct host_vm_change hvc;
362
363 mm = &init_mm;
364 hvc = INIT_HVC(mm, force, userspace);
365 for (addr = start; addr < end;) {
366 pgd = pgd_offset(mm, addr);
367 if (!pgd_present(*pgd)) {
368 last = ADD_ROUND(addr, PGDIR_SIZE);
369 if (last > end)
370 last = end;
371 if (pgd_newpage(*pgd)) {
372 updated = 1;
373 err = add_munmap(addr, last - addr, &hvc);
374 if (err < 0)
375 panic("munmap failed, errno = %d\n",
376 -err);
377 }
378 addr = last;
379 continue;
380 }
381
382 p4d = p4d_offset(pgd, addr);
383 if (!p4d_present(*p4d)) {
384 last = ADD_ROUND(addr, P4D_SIZE);
385 if (last > end)
386 last = end;
387 if (p4d_newpage(*p4d)) {
388 updated = 1;
389 err = add_munmap(addr, last - addr, &hvc);
390 if (err < 0)
391 panic("munmap failed, errno = %d\n",
392 -err);
393 }
394 addr = last;
395 continue;
396 }
397
398 pud = pud_offset(p4d, addr);
399 if (!pud_present(*pud)) {
400 last = ADD_ROUND(addr, PUD_SIZE);
401 if (last > end)
402 last = end;
403 if (pud_newpage(*pud)) {
404 updated = 1;
405 err = add_munmap(addr, last - addr, &hvc);
406 if (err < 0)
407 panic("munmap failed, errno = %d\n",
408 -err);
409 }
410 addr = last;
411 continue;
412 }
413
414 pmd = pmd_offset(pud, addr);
415 if (!pmd_present(*pmd)) {
416 last = ADD_ROUND(addr, PMD_SIZE);
417 if (last > end)
418 last = end;
419 if (pmd_newpage(*pmd)) {
420 updated = 1;
421 err = add_munmap(addr, last - addr, &hvc);
422 if (err < 0)
423 panic("munmap failed, errno = %d\n",
424 -err);
425 }
426 addr = last;
427 continue;
428 }
429
430 pte = pte_offset_kernel(pmd, addr);
431 if (!pte_present(*pte) || pte_newpage(*pte)) {
432 updated = 1;
433 err = add_munmap(addr, PAGE_SIZE, &hvc);
434 if (err < 0)
435 panic("munmap failed, errno = %d\n",
436 -err);
437 if (pte_present(*pte))
438 err = add_mmap(addr, pte_val(*pte) & PAGE_MASK,
439 PAGE_SIZE, 0, &hvc);
440 }
441 else if (pte_newprot(*pte)) {
442 updated = 1;
443 err = add_mprotect(addr, PAGE_SIZE, 0, &hvc);
444 }
445 addr += PAGE_SIZE;
446 }
447 if (!err)
448 err = do_ops(&hvc, hvc.index, 1);
449
450 if (err < 0)
451 panic("flush_tlb_kernel failed, errno = %d\n", err);
452 return updated;
453}
454
455void flush_tlb_page(struct vm_area_struct *vma, unsigned long address)
456{
457 pgd_t *pgd;
458 p4d_t *p4d;
459 pud_t *pud;
460 pmd_t *pmd;
461 pte_t *pte;
462 struct mm_struct *mm = vma->vm_mm;
463 void *flush = NULL;
464 int r, w, x, prot, err = 0;
465 struct mm_id *mm_id;
466
467 address &= PAGE_MASK;
468
469 pgd = pgd_offset(mm, address);
470 if (!pgd_present(*pgd))
471 goto kill;
472
473 p4d = p4d_offset(pgd, address);
474 if (!p4d_present(*p4d))
475 goto kill;
476
477 pud = pud_offset(p4d, address);
478 if (!pud_present(*pud))
479 goto kill;
480
481 pmd = pmd_offset(pud, address);
482 if (!pmd_present(*pmd))
483 goto kill;
484
485 pte = pte_offset_kernel(pmd, address);
486
487 r = pte_read(*pte);
488 w = pte_write(*pte);
489 x = pte_exec(*pte);
490 if (!pte_young(*pte)) {
491 r = 0;
492 w = 0;
493 } else if (!pte_dirty(*pte)) {
494 w = 0;
495 }
496
497 mm_id = &mm->context.id;
498 prot = ((r ? UM_PROT_READ : 0) | (w ? UM_PROT_WRITE : 0) |
499 (x ? UM_PROT_EXEC : 0));
500 if (pte_newpage(*pte)) {
501 if (pte_present(*pte)) {
502 unsigned long long offset;
503 int fd;
504
505 fd = phys_mapping(pte_val(*pte) & PAGE_MASK, &offset);
506 err = map(mm_id, address, PAGE_SIZE, prot, fd, offset,
507 1, &flush);
508 }
509 else err = unmap(mm_id, address, PAGE_SIZE, 1, &flush);
510 }
511 else if (pte_newprot(*pte))
512 err = protect(mm_id, address, PAGE_SIZE, prot, 1, &flush);
513
514 if (err) {
515 if (err == -ENOMEM)
516 report_enomem();
517
518 goto kill;
519 }
520
521 *pte = pte_mkuptodate(*pte);
522
523 return;
524
525kill:
526 printk(KERN_ERR "Failed to flush page for address 0x%lx\n", address);
527 force_sig(SIGKILL);
528}
529
530void flush_tlb_all(void)
531{
532
533
534
535
536 if (atomic_read(¤t->mm->mm_users) == 0)
537 return;
538
539 flush_tlb_mm(current->mm);
540}
541
542void flush_tlb_kernel_range(unsigned long start, unsigned long end)
543{
544 flush_tlb_kernel_range_common(start, end);
545}
546
547void flush_tlb_kernel_vm(void)
548{
549 flush_tlb_kernel_range_common(start_vm, end_vm);
550}
551
552void __flush_tlb_one(unsigned long addr)
553{
554 flush_tlb_kernel_range_common(addr, addr + PAGE_SIZE);
555}
556
557static void fix_range(struct mm_struct *mm, unsigned long start_addr,
558 unsigned long end_addr, int force)
559{
560
561
562
563
564 if (atomic_read(&mm->mm_users) == 0)
565 return;
566
567 fix_range_common(mm, start_addr, end_addr, force);
568}
569
570void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
571 unsigned long end)
572{
573 if (vma->vm_mm == NULL)
574 flush_tlb_kernel_range_common(start, end);
575 else fix_range(vma->vm_mm, start, end, 0);
576}
577EXPORT_SYMBOL(flush_tlb_range);
578
579void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start,
580 unsigned long end)
581{
582 fix_range(mm, start, end, 0);
583}
584
585void flush_tlb_mm(struct mm_struct *mm)
586{
587 struct vm_area_struct *vma = mm->mmap;
588
589 while (vma != NULL) {
590 fix_range(mm, vma->vm_start, vma->vm_end, 0);
591 vma = vma->vm_next;
592 }
593}
594
595void force_flush_all(void)
596{
597 struct mm_struct *mm = current->mm;
598 struct vm_area_struct *vma = mm->mmap;
599
600 while (vma != NULL) {
601 fix_range(mm, vma->vm_start, vma->vm_end, 1);
602 vma = vma->vm_next;
603 }
604}
605
