/* * kmap/page table map and unmap support routines * * Copyright 1999,2000 Hewlett-Packard Company * Copyright 2000 John Marvin <jsm at hp.com> * Copyright 2000 Grant Grundler <grundler at parisc-linux.org> * Copyright 2000 Philipp Rumpf <prumpf@tux.org> * * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ /* ** Stolen mostly from arch/parisc/kernel/pci-dma.c */ #include <linux/types.h> #include <linux/mm.h> #include <linux/string.h> #include <linux/pci.h> #include <linux/slab.h> #include <linux/vmalloc.h> #include <asm/uaccess.h> #include <asm/pgalloc.h> #include <asm/io.h> #include <asm/page.h> /* get_order */ #undef flush_cache_all #define flush_cache_all flush_all_caches typedef void (*pte_iterator_t) (pte_t * pte, unsigned long arg); #if 0 /* XXX This routine could be used with iterate_page() to replace * unmap_uncached_page() and save a little code space but I didn't * do that since I'm not certain whether this is the right path. -PB */ static void unmap_cached_pte(pte_t * pte, unsigned long addr, unsigned long arg) { pte_t page = *pte; pte_clear(&init_mm, addr, pte); if (!pte_none(page)) { if (pte_present(page)) { unsigned long map_nr = pte_pagenr(page); if (map_nr < max_mapnr) __free_page(mem_map + map_nr); } else { printk(KERN_CRIT "Whee.. Swapped out page in kernel page table\n"); } } } #endif /* These two routines should probably check a few things... */ static void set_uncached(pte_t * pte, unsigned long arg) { pte_val(*pte) |= _PAGE_NO_CACHE; } static void set_cached(pte_t * pte, unsigned long arg) { pte_val(*pte) &= ~_PAGE_NO_CACHE; } static inline void iterate_pte(pmd_t * pmd, unsigned long address, unsigned long size, pte_iterator_t op, unsigned long arg) { pte_t *pte; unsigned long end; if (pmd_none(*pmd)) return; if (pmd_bad(*pmd)) { pmd_ERROR(*pmd); pmd_clear(pmd); return; } pte = pte_offset(pmd, address); address &= ~PMD_MASK; end = address + size; if (end > PMD_SIZE) end = PMD_SIZE; do { op(pte, arg); address += PAGE_SIZE; pte++; } while (address < end); } static inline void iterate_pmd(pgd_t * dir, unsigned long address, unsigned long size, pte_iterator_t op, unsigned long arg) { pmd_t *pmd; unsigned long end; if (pgd_none(*dir)) return; if (pgd_bad(*dir)) { pgd_ERROR(*dir); pgd_clear(dir); return; } pmd = pmd_offset(dir, address); address &= ~PGDIR_MASK; end = address + size; if (end > PGDIR_SIZE) end = PGDIR_SIZE; do { iterate_pte(pmd, address, end - address, op, arg); address = (address + PMD_SIZE) & PMD_MASK; pmd++; } while (address < end); } static void iterate_pages(unsigned long address, unsigned long size, pte_iterator_t op, unsigned long arg) { pgd_t *dir; unsigned long end = address + size; dir = pgd_offset_k(address); flush_cache_all(); do { iterate_pmd(dir, address, end - address, op, arg); address = (address + PGDIR_SIZE) & PGDIR_MASK; dir++; } while (address && (address < end)); flush_tlb_all(); } void kernel_set_cachemode(unsigned long vaddr, unsigned long size, int what) { switch (what) { case IOMAP_FULL_CACHING: iterate_pages(vaddr, size, set_cached, 0); flush_tlb_range(NULL, vaddr, size); break; case IOMAP_NOCACHE_SER: iterate_pages(vaddr, size, set_uncached, 0); flush_tlb_range(NULL, vaddr, size); break; default: printk(KERN_CRIT "kernel_set_cachemode mode %d not understood\n", what); break; } }