From 9d0e59a34116f5ee48efc9a397fb09aaedc3b2f0 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Mon, 30 Apr 2007 09:57:40 -0600 Subject: [PATCH] [VOYAGER] Use modern techniques to setup and teardown low identiy mappings. This is a trivial and hopefully obviously correct patch to setup and teardown the identity mappings the way the rest of arch/i386 does. My new page table setup code will break some assumptions below so this is my attempt to keep voyager working. Signed-off-by: Eric W. Biederman Signed-off-by: James Bottomley --- arch/i386/mach-voyager/voyager_smp.c | 36 ++++------------------------ 1 file changed, 5 insertions(+), 31 deletions(-) diff --git a/arch/i386/mach-voyager/voyager_smp.c b/arch/i386/mach-voyager/voyager_smp.c index a126baeaa423..535fb9e754fb 100644 --- a/arch/i386/mach-voyager/voyager_smp.c +++ b/arch/i386/mach-voyager/voyager_smp.c @@ -536,15 +536,6 @@ do_boot_cpu(__u8 cpu) & ~( voyager_extended_vic_processors & voyager_allowed_boot_processors); - /* For the 486, we can't use the 4Mb page table trick, so - * must map a region of memory */ -#ifdef CONFIG_M486 - int i; - unsigned long *page_table_copies = (unsigned long *) - __get_free_page(GFP_KERNEL); -#endif - pgd_t orig_swapper_pg_dir0; - /* This is an area in head.S which was used to set up the * initial kernel stack. We need to alter this to give the * booting CPU a new stack (taken from its idle process) */ @@ -595,24 +586,11 @@ do_boot_cpu(__u8 cpu) VDEBUG(("VOYAGER SMP: Booting CPU%d at 0x%lx[%x:%x], stack %p\n", cpu, (unsigned long)hijack_source.val, hijack_source.idt.Segment, hijack_source.idt.Offset, stack_start.esp)); - /* set the original swapper_pg_dir[0] to map 0 to 4Mb transparently - * (so that the booting CPU can find start_32 */ - orig_swapper_pg_dir0 = swapper_pg_dir[0]; -#ifdef CONFIG_M486 - if(page_table_copies == NULL) - panic("No free memory for 486 page tables\n"); - for(i = 0; i < PAGE_SIZE/sizeof(unsigned long); i++) - page_table_copies[i] = (i * PAGE_SIZE) - | _PAGE_RW | _PAGE_USER | _PAGE_PRESENT; - ((unsigned long *)swapper_pg_dir)[0] = - ((virt_to_phys(page_table_copies)) & PAGE_MASK) - | _PAGE_RW | _PAGE_USER | _PAGE_PRESENT; -#else - ((unsigned long *)swapper_pg_dir)[0] = - (virt_to_phys(pg0) & PAGE_MASK) - | _PAGE_RW | _PAGE_USER | _PAGE_PRESENT; -#endif + /* init lowmem identity mapping */ + clone_pgd_range(swapper_pg_dir, swapper_pg_dir + USER_PGD_PTRS, + min_t(unsigned long, KERNEL_PGD_PTRS, USER_PGD_PTRS)); + flush_tlb_all(); if(quad_boot) { printk("CPU %d: non extended Quad boot\n", cpu); @@ -655,11 +633,7 @@ do_boot_cpu(__u8 cpu) udelay(100); } /* reset the page table */ - swapper_pg_dir[0] = orig_swapper_pg_dir0; - local_flush_tlb(); -#ifdef CONFIG_M486 - free_page((unsigned long)page_table_copies); -#endif + zap_low_mappings(); if (cpu_booted_map) { VDEBUG(("CPU%d: Booted successfully, back in CPU %d\n",