source: mainline/kernel/arch/ia32/src/mm/page.c@ 7e752b2

/*
 * Copyright (c) 2001-2004 Jakub Jermar
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup ia32mm
 * @{
 */
/** @file
 */

#include <arch/mm/page.h>
#include <genarch/mm/page_pt.h>
#include <arch/mm/frame.h>
#include <mm/frame.h>
#include <mm/page.h>
#include <mm/as.h>
#include <typedefs.h>
#include <align.h>
#include <config.h>
#include <func.h>
#include <arch/interrupt.h>
#include <arch/asm.h>
#include <debug.h>
#include <memstr.h>
#include <print.h>
#include <interrupt.h>

void page_arch_init(void)
{
        uintptr_t cur;
        int flags;
        
        if (config.cpu_active == 1) {
                page_mapping_operations = &pt_mapping_operations;
        
                /*
                 * PA2KA(identity) mapping for all frames until last_frame.
                 */
                page_table_lock(AS_KERNEL, true);
                for (cur = 0; cur < last_frame; cur += FRAME_SIZE) {
                        flags = PAGE_CACHEABLE | PAGE_WRITE;
                        if ((PA2KA(cur) >= config.base) && (PA2KA(cur) < config.base + config.kernel_size))
                                flags |= PAGE_GLOBAL;
                        page_mapping_insert(AS_KERNEL, PA2KA(cur), cur, flags);
                }
                page_table_unlock(AS_KERNEL, true);
                
                exc_register(14, "page_fault", true, (iroutine_t) page_fault);
                write_cr3((uintptr_t) AS_KERNEL->genarch.page_table);
        } else
                write_cr3((uintptr_t) AS_KERNEL->genarch.page_table);
        
        paging_on();
}


uintptr_t hw_map(uintptr_t physaddr, size_t size)
{
        if (last_frame + ALIGN_UP(size, PAGE_SIZE) > KA2PA(KERNEL_ADDRESS_SPACE_END_ARCH))
                panic("Unable to map physical memory %p (%zu bytes).",
                    (void *) physaddr, size);
        
        uintptr_t virtaddr = PA2KA(last_frame);
        pfn_t i;
        page_table_lock(AS_KERNEL, true);
        for (i = 0; i < ADDR2PFN(ALIGN_UP(size, PAGE_SIZE)); i++) {
                uintptr_t addr = PFN2ADDR(i);
                page_mapping_insert(AS_KERNEL, virtaddr + addr, physaddr + addr, PAGE_NOT_CACHEABLE | PAGE_WRITE);
        }
        page_table_unlock(AS_KERNEL, true);
        
        last_frame = ALIGN_UP(last_frame + size, FRAME_SIZE);
        
        return virtaddr;
}

void page_fault(unsigned int n __attribute__((unused)), istate_t *istate)
{
        uintptr_t page;
        pf_access_t access;
        
        page = read_cr2();
                
        if (istate->error_word & PFERR_CODE_RSVD)
                panic("Reserved bit set in page directory.");
        
        if (istate->error_word & PFERR_CODE_RW)
                access = PF_ACCESS_WRITE;
        else
                access = PF_ACCESS_READ;
        
        if (as_page_fault(page, access, istate) == AS_PF_FAULT) {
                fault_if_from_uspace(istate, "Page fault: %#x.", page);
                panic_memtrap(istate, access, page, NULL);
        }
}

/** @}
 */