1 /* 2 * Copyright © 2008 Ingo Molnar 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License as published by 6 * the Free Software Foundation; either version 2 of the License, or 7 * (at your option) any later version. 8 * 9 * This program is distributed in the hope that it will be useful, but 10 * WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 12 * General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License along 15 * with this program; if not, write to the Free Software Foundation, Inc., 16 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. 17 */ 18 19 #include <asm/iomap.h> 20 #include <linux/module.h> 21 22 /* Map 'pfn' using fixed map 'type' and protections 'prot' 23 */ 24 void * 25 iomap_atomic_prot_pfn(unsigned long pfn, enum km_type type, pgprot_t prot) 26 { 27 enum fixed_addresses idx; 28 unsigned long vaddr; 29 30 pagefault_disable(); 31 32 idx = type + KM_TYPE_NR*smp_processor_id(); 33 vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx); 34 set_pte(kmap_pte-idx, pfn_pte(pfn, prot)); 35 arch_flush_lazy_mmu_mode(); 36 37 return (void*) vaddr; 38 } 39 EXPORT_SYMBOL_GPL(iomap_atomic_prot_pfn); 40 41 void 42 iounmap_atomic(void *kvaddr, enum km_type type) 43 { 44 unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK; 45 enum fixed_addresses idx = type + KM_TYPE_NR*smp_processor_id(); 46 47 /* 48 * Force other mappings to Oops if they'll try to access this pte 49 * without first remap it. Keeping stale mappings around is a bad idea 50 * also, in case the page changes cacheability attributes or becomes 51 * a protected page in a hypervisor. 52 */ 53 if (vaddr == __fix_to_virt(FIX_KMAP_BEGIN+idx)) 54 kpte_clear_flush(kmap_pte-idx, vaddr); 55 56 arch_flush_lazy_mmu_mode(); 57 pagefault_enable(); 58 } 59 EXPORT_SYMBOL_GPL(iounmap_atomic); 60