Commit dec7305d authored by Max Filippov's avatar Max Filippov
Browse files

xtensa: allow fixmap and kmap span more than one page table 



To support aliasing cache both kmap region sizes are multiplied by the
number of data cache colors. After that expansion page tables that cover
kmap regions may become larger than one page. Correctly allocate and
initialize page tables in this case.

Signed-off-by: default avatarMax Filippov <jcmvbkbc@gmail.com>
parent 22def768

arch/xtensa/mm/mmu.c

+22 −16
Original line number Diff line number Diff line
@@ -18,32 +18,38 @@ 
#include <asm/io.h>



#if defined(CONFIG_HIGHMEM)

static void * __init init_pmd(unsigned long vaddr)

static void * __init init_pmd(unsigned long vaddr, unsigned long n_pages)

{

	pgd_t *pgd = pgd_offset_k(vaddr);

	pmd_t *pmd = pmd_offset(pgd, vaddr);

	pte_t *pte;

	unsigned long i;



	if (pmd_none(*pmd)) {

		unsigned i;

		pte_t *pte = alloc_bootmem_low_pages(PAGE_SIZE);

	n_pages = ALIGN(n_pages, PTRS_PER_PTE);



		for (i = 0; i < 1024; i++)

	pr_debug("%s: vaddr: 0x%08lx, n_pages: %ld\n",

		 __func__, vaddr, n_pages);



	pte = alloc_bootmem_low_pages(n_pages * sizeof(pte_t));



	for (i = 0; i < n_pages; ++i)

		pte_clear(NULL, 0, pte + i);



		set_pmd(pmd, __pmd(((unsigned long)pte) & PAGE_MASK));

		BUG_ON(pte != pte_offset_kernel(pmd, 0));

		pr_debug("%s: vaddr: 0x%08lx, pmd: 0x%p, pte: 0x%p\n",

			 __func__, vaddr, pmd, pte);

		return pte;

	} else {

		return pte_offset_kernel(pmd, 0);

	for (i = 0; i < n_pages; i += PTRS_PER_PTE, ++pmd) {

		pte_t *cur_pte = pte + i;



		BUG_ON(!pmd_none(*pmd));

		set_pmd(pmd, __pmd(((unsigned long)cur_pte) & PAGE_MASK));

		BUG_ON(cur_pte != pte_offset_kernel(pmd, 0));

		pr_debug("%s: pmd: 0x%p, pte: 0x%p\n",

			 __func__, pmd, cur_pte);

	}

	return pte;

}



static void __init fixedrange_init(void)

{

	BUILD_BUG_ON(FIXADDR_SIZE > PMD_SIZE);

	init_pmd(__fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK);

	init_pmd(__fix_to_virt(0), __end_of_fixed_addresses);

}

#endif
@@ -52,7 +58,7 @@ void __init paging_init(void) 
	memset(swapper_pg_dir, 0, PAGE_SIZE);

#ifdef CONFIG_HIGHMEM

	fixedrange_init();

	pkmap_page_table = init_pmd(PKMAP_BASE);

	pkmap_page_table = init_pmd(PKMAP_BASE, LAST_PKMAP);

	kmap_init();

#endif

}

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