Commit 640710a3 authored by Chris Metcalf's avatar Chris Metcalf
Browse files

tile: add virt_to_kpte() API and clean up and document behavior 



We use virt_to_pte(NULL, va) a lot, which isn't very obvious.
I added virt_to_kpte(va) as a more obvious wrapper function,
that also validates the va as being a kernel adddress.

And, I fixed the semantics of virt_to_pte() so that we handle
the pud and pmd the same way, and we now document the fact that
we handle the final pte level differently.

Signed-off-by: default avatarChris Metcalf <cmetcalf@tilera.com>
parent 49cf78ef

arch/tile/include/asm/mmu_context.h

+1 −1
Original line number Diff line number Diff line
@@ -45,7 +45,7 @@ static inline void __install_page_table(pgd_t *pgdir, int asid, pgprot_t prot) 


static inline void install_page_table(pgd_t *pgdir, int asid)

{

	pte_t *ptep = virt_to_pte(NULL, (unsigned long)pgdir);

	pte_t *ptep = virt_to_kpte((unsigned long)pgdir);

	__install_page_table(pgdir, asid, *ptep);

}

arch/tile/include/asm/page.h

+1 −0
Original line number Diff line number Diff line
@@ -328,6 +328,7 @@ static inline int pfn_valid(unsigned long pfn) 


struct mm_struct;

extern pte_t *virt_to_pte(struct mm_struct *mm, unsigned long addr);

extern pte_t *virt_to_kpte(unsigned long kaddr);



#endif /* !__ASSEMBLY__ */

arch/tile/kernel/setup.c

+3 −3
Original line number Diff line number Diff line
@@ -1600,7 +1600,7 @@ void __init setup_per_cpu_areas(void) 


			/* Update the vmalloc mapping and page home. */

			unsigned long addr = (unsigned long)ptr + i;

			pte_t *ptep = virt_to_pte(NULL, addr);

			pte_t *ptep = virt_to_kpte(addr);

			pte_t pte = *ptep;

			BUG_ON(pfn != pte_pfn(pte));

			pte = hv_pte_set_mode(pte, HV_PTE_MODE_CACHE_TILE_L3);
@@ -1609,12 +1609,12 @@ void __init setup_per_cpu_areas(void) 


			/* Update the lowmem mapping for consistency. */

			lowmem_va = (unsigned long)pfn_to_kaddr(pfn);

			ptep = virt_to_pte(NULL, lowmem_va);

			ptep = virt_to_kpte(lowmem_va);

			if (pte_huge(*ptep)) {

				printk(KERN_DEBUG "early shatter of huge page"

				       " at %#lx\n", lowmem_va);

				shatter_pmd((pmd_t *)ptep);

				ptep = virt_to_pte(NULL, lowmem_va);

				ptep = virt_to_kpte(lowmem_va);

				BUG_ON(pte_huge(*ptep));

			}

			BUG_ON(pfn != pte_pfn(*ptep));

arch/tile/mm/homecache.c

+3 −3
Original line number Diff line number Diff line
@@ -200,7 +200,7 @@ void homecache_finv_map_page(struct page *page, int home) 
#else

	va = __fix_to_virt(FIX_HOMECACHE_BEGIN + smp_processor_id());

#endif

	ptep = virt_to_pte(NULL, (unsigned long)va);

	ptep = virt_to_kpte(va);

	pte = pfn_pte(page_to_pfn(page), PAGE_KERNEL);

	__set_pte(ptep, pte_set_home(pte, home));

	homecache_finv_page_va((void *)va, home);
@@ -385,7 +385,7 @@ int page_home(struct page *page) 
		return initial_page_home();

	} else {

		unsigned long kva = (unsigned long)page_address(page);

		return pte_to_home(*virt_to_pte(NULL, kva));

		return pte_to_home(*virt_to_kpte(kva));

	}

}

EXPORT_SYMBOL(page_home);
@@ -404,7 +404,7 @@ void homecache_change_page_home(struct page *page, int order, int home) 
		     NULL, 0);



	for (i = 0; i < pages; ++i, kva += PAGE_SIZE) {

		pte_t *ptep = virt_to_pte(NULL, kva);

		pte_t *ptep = virt_to_kpte(kva);

		pte_t pteval = *ptep;

		BUG_ON(!pte_present(pteval) || pte_huge(pteval));

		__set_pte(ptep, pte_set_home(pteval, home));

arch/tile/mm/init.c

+2 −2
Original line number Diff line number Diff line
@@ -951,7 +951,7 @@ static void mark_w1data_ro(void) 
	BUG_ON((addr & (PAGE_SIZE-1)) != 0);

	for (; addr <= (unsigned long)__w1data_end - 1; addr += PAGE_SIZE) {

		unsigned long pfn = kaddr_to_pfn((void *)addr);

		pte_t *ptep = virt_to_pte(NULL, addr);

		pte_t *ptep = virt_to_kpte(addr);

		BUG_ON(pte_huge(*ptep));   /* not relevant for kdata_huge */

		set_pte_at(&init_mm, addr, ptep, pfn_pte(pfn, PAGE_KERNEL_RO));

	}
@@ -997,7 +997,7 @@ static void free_init_pages(char *what, unsigned long begin, unsigned long end) 
		 */

		int pfn = kaddr_to_pfn((void *)addr);

		struct page *page = pfn_to_page(pfn);

		pte_t *ptep = virt_to_pte(NULL, addr);

		pte_t *ptep = virt_to_kpte(addr);

		if (!initfree) {

			/*

			 * If debugging page accesses then do not free

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