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-rw-r--r--arch/xtensa/mm/init.c252
1 files changed, 15 insertions, 237 deletions
diff --git a/arch/xtensa/mm/init.c b/arch/xtensa/mm/init.c
index 8415c76f11c2..b3086f34a8e7 100644
--- a/arch/xtensa/mm/init.c
+++ b/arch/xtensa/mm/init.c
@@ -15,40 +15,24 @@
15 * Kevin Chea 15 * Kevin Chea
16 */ 16 */
17 17
18#include <linux/init.h>
19#include <linux/signal.h>
20#include <linux/sched.h>
21#include <linux/kernel.h> 18#include <linux/kernel.h>
22#include <linux/errno.h> 19#include <linux/errno.h>
23#include <linux/string.h>
24#include <linux/types.h>
25#include <linux/ptrace.h>
26#include <linux/bootmem.h> 20#include <linux/bootmem.h>
27#include <linux/swap.h> 21#include <linux/swap.h>
22#include <linux/mman.h>
23#include <linux/nodemask.h>
24#include <linux/mm.h>
25#include <linux/slab.h>
28 26
29#include <asm/pgtable.h> 27#include <asm/pgtable.h>
30#include <asm/bootparam.h> 28#include <asm/bootparam.h>
31#include <asm/mmu_context.h> 29#include <asm/mmu_context.h>
32#include <asm/tlb.h> 30#include <asm/tlb.h>
33#include <asm/tlbflush.h>
34#include <asm/page.h> 31#include <asm/page.h>
35#include <asm/pgalloc.h> 32#include <asm/pgalloc.h>
36#include <asm/pgtable.h>
37
38 33
39#define DEBUG 0
40 34
41DEFINE_PER_CPU(struct mmu_gather, mmu_gathers); 35DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
42//static DEFINE_SPINLOCK(tlb_lock);
43
44/*
45 * This flag is used to indicate that the page was mapped and modified in
46 * kernel space, so the cache is probably dirty at that address.
47 * If cache aliasing is enabled and the page color mismatches, update_mmu_cache
48 * synchronizes the caches if this bit is set.
49 */
50
51#define PG_cache_clean PG_arch_1
52 36
53/* References to section boundaries */ 37/* References to section boundaries */
54 38
@@ -323,228 +307,22 @@ void show_mem(void)
323 printk("%d free pages\n", free); 307 printk("%d free pages\n", free);
324} 308}
325 309
326/* ------------------------------------------------------------------------- */ 310struct kmem_cache *pgtable_cache __read_mostly;
327
328#if (DCACHE_WAY_SIZE > PAGE_SIZE)
329
330/*
331 * With cache aliasing, the page color of the page in kernel space and user
332 * space might mismatch. We temporarily map the page to a different virtual
333 * address with the same color and clear the page there.
334 */
335
336void clear_user_page(void *kaddr, unsigned long vaddr, struct page* page)
337{
338
339 /* There shouldn't be any entries for this page. */
340
341 __flush_invalidate_dcache_page_phys(__pa(page_address(page)));
342
343 if (!PAGE_COLOR_EQ(vaddr, kaddr)) {
344 unsigned long v, p;
345
346 /* Temporarily map page to DTLB_WAY_DCACHE_ALIAS0. */
347
348 spin_lock(&tlb_lock);
349
350 p = (unsigned long)pte_val((mk_pte(page,PAGE_KERNEL)));
351 kaddr = (void*)PAGE_COLOR_MAP0(vaddr);
352 v = (unsigned long)kaddr | DTLB_WAY_DCACHE_ALIAS0;
353 __asm__ __volatile__("wdtlb %0,%1; dsync" : :"a" (p), "a" (v));
354
355 clear_page(kaddr);
356
357 spin_unlock(&tlb_lock);
358 } else {
359 clear_page(kaddr);
360 }
361
362 /* We need to make sure that i$ and d$ are coherent. */
363
364 clear_bit(PG_cache_clean, &page->flags);
365}
366
367/*
368 * With cache aliasing, we have to make sure that the page color of the page
369 * in kernel space matches that of the virtual user address before we read
370 * the page. If the page color differ, we create a temporary DTLB entry with
371 * the corrent page color and use this 'temporary' address as the source.
372 * We then use the same approach as in clear_user_page and copy the data
373 * to the kernel space and clear the PG_cache_clean bit to synchronize caches
374 * later.
375 *
376 * Note:
377 * Instead of using another 'way' for the temporary DTLB entry, we could
378 * probably use the same entry that points to the kernel address (after
379 * saving the original value and restoring it when we are done).
380 */
381 311
382void copy_user_page(void* to, void* from, unsigned long vaddr, 312static void pgd_ctor(void *addr, struct kmem_cache *cache, unsigned long flags)
383 struct page* to_page)
384{ 313{
385 /* There shouldn't be any entries for the new page. */ 314 pte_t* ptep = (pte_t*)addr;
386 315 int i;
387 __flush_invalidate_dcache_page_phys(__pa(page_address(to_page)));
388
389 spin_lock(&tlb_lock);
390
391 if (!PAGE_COLOR_EQ(vaddr, from)) {
392 unsigned long v, p, t;
393
394 __asm__ __volatile__ ("pdtlb %1,%2; rdtlb1 %0,%1"
395 : "=a"(p), "=a"(t) : "a"(from));
396 from = (void*)PAGE_COLOR_MAP0(vaddr);
397 v = (unsigned long)from | DTLB_WAY_DCACHE_ALIAS0;
398 __asm__ __volatile__ ("wdtlb %0,%1; dsync" ::"a" (p), "a" (v));
399 }
400
401 if (!PAGE_COLOR_EQ(vaddr, to)) {
402 unsigned long v, p;
403
404 p = (unsigned long)pte_val((mk_pte(to_page,PAGE_KERNEL)));
405 to = (void*)PAGE_COLOR_MAP1(vaddr);
406 v = (unsigned long)to | DTLB_WAY_DCACHE_ALIAS1;
407 __asm__ __volatile__ ("wdtlb %0,%1; dsync" ::"a" (p), "a" (v));
408 }
409 copy_page(to, from);
410
411 spin_unlock(&tlb_lock);
412
413 /* We need to make sure that i$ and d$ are coherent. */
414
415 clear_bit(PG_cache_clean, &to_page->flags);
416}
417
418
419
420/*
421 * Any time the kernel writes to a user page cache page, or it is about to
422 * read from a page cache page this routine is called.
423 *
424 * Note:
425 * The kernel currently only provides one architecture bit in the page
426 * flags that we use for I$/D$ coherency. Maybe, in future, we can
427 * use a sepearte bit for deferred dcache aliasing:
428 * If the page is not mapped yet, we only need to set a flag,
429 * if mapped, we need to invalidate the page.
430 */
431// FIXME: we probably need this for WB caches not only for Page Coloring..
432
433void flush_dcache_page(struct page *page)
434{
435 unsigned long addr = __pa(page_address(page));
436 struct address_space *mapping = page_mapping(page);
437
438 __flush_invalidate_dcache_page_phys(addr);
439
440 if (!test_bit(PG_cache_clean, &page->flags))
441 return;
442
443 /* If this page hasn't been mapped, yet, handle I$/D$ coherency later.*/
444#if 0
445 if (mapping && !mapping_mapped(mapping))
446 clear_bit(PG_cache_clean, &page->flags);
447 else
448#endif
449 __invalidate_icache_page_phys(addr);
450}
451
452void flush_cache_range(struct vm_area_struct* vma, unsigned long s,
453 unsigned long e)
454{
455 __flush_invalidate_cache_all();
456}
457
458void flush_cache_page(struct vm_area_struct* vma, unsigned long address,
459 unsigned long pfn)
460{
461 struct page *page = pfn_to_page(pfn);
462
463 /* Remove any entry for the old mapping. */
464
465 if (current->active_mm == vma->vm_mm) {
466 unsigned long addr = __pa(page_address(page));
467 __flush_invalidate_dcache_page_phys(addr);
468 if ((vma->vm_flags & VM_EXEC) != 0)
469 __invalidate_icache_page_phys(addr);
470 } else {
471 BUG();
472 }
473}
474
475#endif /* (DCACHE_WAY_SIZE > PAGE_SIZE) */
476
477
478pte_t* pte_alloc_one_kernel (struct mm_struct* mm, unsigned long addr)
479{
480 pte_t* pte = (pte_t*)__get_free_pages(GFP_KERNEL|__GFP_REPEAT, 0);
481 if (likely(pte)) {
482 pte_t* ptep = (pte_t*)(pte_val(*pte) + PAGE_OFFSET);
483 int i;
484 for (i = 0; i < 1024; i++, ptep++)
485 pte_clear(mm, addr, ptep);
486 }
487 return pte;
488}
489
490struct page* pte_alloc_one(struct mm_struct *mm, unsigned long addr)
491{
492 struct page *page;
493
494 page = alloc_pages(GFP_KERNEL | __GFP_REPEAT, 0);
495
496 if (likely(page)) {
497 pte_t* ptep = kmap_atomic(page, KM_USER0);
498 int i;
499 316
500 for (i = 0; i < 1024; i++, ptep++) 317 for (i = 0; i < 1024; i++, ptep++)
501 pte_clear(mm, addr, ptep); 318 pte_clear(NULL, 0, ptep);
502 319
503 kunmap_atomic(ptep, KM_USER0);
504 }
505 return page;
506} 320}
507 321
508 322void __init pgtable_cache_init(void)
509/*
510 * Handle D$/I$ coherency.
511 *
512 * Note:
513 * We only have one architecture bit for the page flags, so we cannot handle
514 * cache aliasing, yet.
515 */
516
517void
518update_mmu_cache(struct vm_area_struct * vma, unsigned long addr, pte_t pte)
519{ 323{
520 unsigned long pfn = pte_pfn(pte); 324 pgtable_cache = kmem_cache_create("pgd",
521 struct page *page; 325 PAGE_SIZE, PAGE_SIZE,
522 unsigned long vaddr = addr & PAGE_MASK; 326 SLAB_HWCACHE_ALIGN,
523 327 pgd_ctor);
524 if (!pfn_valid(pfn))
525 return;
526
527 page = pfn_to_page(pfn);
528
529 invalidate_itlb_mapping(addr);
530 invalidate_dtlb_mapping(addr);
531
532 /* We have a new mapping. Use it. */
533
534 write_dtlb_entry(pte, dtlb_probe(addr));
535
536 /* If the processor can execute from this page, synchronize D$/I$. */
537
538 if ((vma->vm_flags & VM_EXEC) != 0) {
539
540 write_itlb_entry(pte, itlb_probe(addr));
541
542 /* Synchronize caches, if not clean. */
543
544 if (!test_and_set_bit(PG_cache_clean, &page->flags)) {
545 __flush_dcache_page(vaddr);
546 __invalidate_icache_page(vaddr);
547 }
548 }
549} 328}
550