diff options
| author | David S. Miller <davem@davemloft.net> | 2014-09-26 21:19:46 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2014-10-05 16:53:38 -0700 |
| commit | ac55c768143aa34cc3789c4820cbb0809a76fd9c (patch) | |
| tree | f6bb7af5b71e7935169a778e3f7e7694fbd1416f /arch/sparc/mm | |
| parent | 473ad7f4fb005d1bb727e4ef27d370d28703a062 (diff) | |
sparc64: Switch to 4-level page tables.
This has become necessary with chips that support more than 43-bits
of physical addressing.
Based almost entirely upon a patch by Bob Picco.
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Bob Picco <bob.picco@oracle.com>
Diffstat (limited to 'arch/sparc/mm')
| -rw-r--r-- | arch/sparc/mm/init_64.c | 31 |
1 files changed, 27 insertions, 4 deletions
diff --git a/arch/sparc/mm/init_64.c b/arch/sparc/mm/init_64.c index bd08ed49bba..091f846e619 100644 --- a/arch/sparc/mm/init_64.c +++ b/arch/sparc/mm/init_64.c @@ -1390,6 +1390,13 @@ static unsigned long __ref kernel_map_range(unsigned long pstart, pmd_t *pmd; pte_t *pte; + if (pgd_none(*pgd)) { + pud_t *new; + + new = __alloc_bootmem(PAGE_SIZE, PAGE_SIZE, PAGE_SIZE); + alloc_bytes += PAGE_SIZE; + pgd_populate(&init_mm, pgd, new); + } pud = pud_offset(pgd, vstart); if (pud_none(*pud)) { pmd_t *new; @@ -1856,7 +1863,12 @@ static void __init sun4v_linear_pte_xor_finalize(void) /* paging_init() sets up the page tables */ static unsigned long last_valid_pfn; -pgd_t swapper_pg_dir[PTRS_PER_PGD]; + +/* These must be page aligned in order to not trigger the + * alignment tests of pgd_bad() and pud_bad(). + */ +pgd_t swapper_pg_dir[PTRS_PER_PGD] __attribute__ ((aligned (PAGE_SIZE))); +static pud_t swapper_pud_dir[PTRS_PER_PUD] __attribute__ ((aligned (PAGE_SIZE))); static void sun4u_pgprot_init(void); static void sun4v_pgprot_init(void); @@ -1911,6 +1923,8 @@ void __init paging_init(void) { unsigned long end_pfn, shift, phys_base; unsigned long real_end, i; + pud_t *pud; + pmd_t *pmd; int node; setup_page_offset(); @@ -2008,9 +2022,18 @@ void __init paging_init(void) memset(swapper_low_pmd_dir, 0, sizeof(swapper_low_pmd_dir)); - /* Now can init the kernel/bad page tables. */ - pud_set(pud_offset(&swapper_pg_dir[0], 0), - swapper_low_pmd_dir + (shift / sizeof(pgd_t))); + /* The kernel page tables we publish into what the rest of the + * world sees must be adjusted so that they see the PAGE_OFFSET + * address of these in-kerenel data structures. However right + * here we must access them from the kernel image side, because + * the trap tables haven't been taken over and therefore we cannot + * take TLB misses in the PAGE_OFFSET linear mappings yet. + */ + pud = swapper_pud_dir + (shift / sizeof(pud_t)); + pgd_set(&swapper_pg_dir[0], pud); + + pmd = swapper_low_pmd_dir + (shift / sizeof(pmd_t)); + pud_set(&swapper_pud_dir[0], pmd); inherit_prom_mappings(); |