0,0 → 1,304 |
/* |
* Copyright (C) 2001-2006 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. |
*/ |
|
/* |
* This file contains address space manipulation functions. |
* Roughly speaking, this is a higher-level client of |
* Virtual Address Translation (VAT) subsystem. |
*/ |
|
#include <mm/as.h> |
#include <mm/page.h> |
#include <mm/frame.h> |
#include <mm/tlb.h> |
#include <mm/heap.h> |
#include <arch/mm/page.h> |
#include <genarch/mm/page_pt.h> |
#include <arch/mm/asid.h> |
#include <arch/mm/as.h> |
#include <arch/types.h> |
#include <typedefs.h> |
#include <synch/spinlock.h> |
#include <config.h> |
#include <list.h> |
#include <panic.h> |
#include <arch/asm.h> |
#include <debug.h> |
#include <memstr.h> |
#include <arch.h> |
#include <print.h> |
|
#define KAS_START_INDEX PTL0_INDEX(KERNEL_ADDRESS_SPACE_START) |
#define KAS_END_INDEX PTL0_INDEX(KERNEL_ADDRESS_SPACE_END) |
#define KAS_INDICES (1+(KAS_END_INDEX-KAS_START_INDEX)) |
|
/* |
* Here we assume that PFN (Physical Frame Numbers) space |
* is smaller than the width of index_t. UNALLOCATED_PFN |
* can be then used to mark mappings wich were not |
* allocated a physical frame. |
*/ |
#define UNALLOCATED_PFN ((index_t) -1) |
|
/** Create address space. */ |
/* |
* FIXME: this interface must be meaningful for all possible VAT |
* (Virtual Address Translation) mechanisms. |
*/ |
as_t *as_create(pte_t *ptl0) |
{ |
as_t *as; |
|
as = (as_t *) malloc(sizeof(as_t)); |
if (as) { |
spinlock_initialize(&as->lock, "as_lock"); |
list_initialize(&as->as_area_head); |
|
as->asid = asid_get(); |
|
as->ptl0 = ptl0; |
if (!as->ptl0) { |
pte_t *src_ptl0, *dst_ptl0; |
|
src_ptl0 = (pte_t *) PA2KA((__address) GET_PTL0_ADDRESS()); |
dst_ptl0 = (pte_t *) frame_alloc(FRAME_KA | FRAME_PANIC, ONE_FRAME, NULL); |
|
// memsetb((__address) dst_ptl0, PAGE_SIZE, 0); |
// memcpy((void *) &dst_ptl0[KAS_START_INDEX], (void *) &src_ptl0[KAS_START_INDEX], KAS_INDICES); |
|
memcpy((void *) dst_ptl0,(void *) src_ptl0, PAGE_SIZE); |
|
as->ptl0 = (pte_t *) KA2PA((__address) dst_ptl0); |
} |
} |
|
return as; |
} |
|
/** Create address space area of common attributes. |
* |
* The created address space area is added to the target address space. |
* |
* @param as Target address space. |
* @param type Type of area. |
* @param size Size of area in multiples of PAGE_SIZE. |
* @param base Base address of area. |
* |
* @return Address space area on success or NULL on failure. |
*/ |
as_area_t *as_area_create(as_t *as, as_area_type_t type, size_t size, __address base) |
{ |
ipl_t ipl; |
as_area_t *a; |
|
if (base % PAGE_SIZE) |
panic("addr not aligned to a page boundary"); |
|
ipl = interrupts_disable(); |
spinlock_lock(&as->lock); |
|
/* |
* TODO: test as_area which is to be created doesn't overlap with an existing one. |
*/ |
|
a = (as_area_t *) malloc(sizeof(as_area_t)); |
if (a) { |
int i; |
|
a->mapping = (index_t *) malloc(size * sizeof(index_t)); |
if (!a->mapping) { |
free(a); |
spinlock_unlock(&as->lock); |
interrupts_restore(ipl); |
return NULL; |
} |
|
for (i=0; i<size; i++) { |
/* |
* Frames will be allocated on-demand by |
* as_page_fault(). |
*/ |
a->mapping[i] = UNALLOCATED_PFN; |
} |
|
spinlock_initialize(&a->lock, "as_area_lock"); |
|
link_initialize(&a->link); |
a->type = type; |
a->size = size; |
a->base = base; |
|
list_append(&a->link, &as->as_area_head); |
|
} |
|
spinlock_unlock(&as->lock); |
interrupts_restore(ipl); |
|
return a; |
} |
|
/** Load mapping for address space area. |
* |
* Initialize a->mapping. |
* |
* @param a Target address space area. |
* @param pfn Array of frame numbers. Number of elements must match with a->mapping. |
*/ |
void as_area_load_mapping(as_area_t *a, index_t *pfn) |
{ |
ipl_t ipl; |
int i; |
|
ipl = interrupts_disable(); |
spinlock_lock(&a->lock); |
|
for (i = 0; i < a->size; i++) { |
ASSERT(a->mapping[i] == UNALLOCATED_PFN); |
a->mapping[i] = pfn[i]; |
} |
|
spinlock_unlock(&a->lock); |
interrupts_restore(ipl); |
} |
|
/** Handle page fault within the current address space. |
* |
* This is the high-level page fault handler. |
* Interrupts are assumed disabled. |
* |
* @param page Faulting page. |
* |
* @return 0 on page fault, 1 if address space operation |
*/ |
int as_page_fault(__address page) |
{ |
int flags; |
link_t *cur; |
as_area_t *a, *area = NULL; |
index_t vpn; |
__address frame; |
|
ASSERT(AS); |
spinlock_lock(&AS->lock); |
|
/* |
* Search this areas of this address space for presence of 'page'. |
*/ |
for (cur = AS->as_area_head.next; cur != &AS->as_area_head; cur = cur->next) { |
a = list_get_instance(cur, as_area_t, link); |
spinlock_lock(&a->lock); |
|
if ((page >= a->base) && (page < a->base + a->size * PAGE_SIZE)) { |
|
/* |
* We found the area containing 'page'. |
* TODO: access checking |
*/ |
|
vpn = (page - a->base) / PAGE_SIZE; |
area = a; |
break; |
} |
|
spinlock_unlock(&a->lock); |
} |
|
if (!area) { |
/* |
* No area contained mapping for 'page'. |
* Signal page fault to low-level handler. |
*/ |
spinlock_unlock(&AS->lock); |
return 0; |
} |
|
/* |
* Note: area->lock is held. |
*/ |
|
/* |
* Decide if a frame needs to be allocated. |
* If so, allocate it and adjust area->mapping map. |
*/ |
if (area->mapping[vpn] == UNALLOCATED_PFN) { |
frame = frame_alloc(0, ONE_FRAME, NULL); |
memsetb(frame, FRAME_SIZE, 0); |
area->mapping[vpn] = frame / FRAME_SIZE; |
} else { |
frame = area->mapping[vpn] * FRAME_SIZE; |
} |
|
switch (area->type) { |
case AS_AREA_TEXT: |
flags = PAGE_EXEC | PAGE_READ | PAGE_USER | PAGE_PRESENT | PAGE_CACHEABLE; |
break; |
case AS_AREA_DATA: |
case AS_AREA_STACK: |
flags = PAGE_READ | PAGE_WRITE | PAGE_USER | PAGE_PRESENT | PAGE_CACHEABLE; |
break; |
default: |
panic("unexpected as_area_type_t %d", area->type); |
} |
|
/* |
* Map 'page' to 'frame'. |
* Note that TLB shootdown is not attempted as only new information is being |
* inserted into page tables. |
*/ |
page_mapping_insert(page, AS->asid, frame, flags, (__address) AS->ptl0); |
|
spinlock_unlock(&area->lock); |
spinlock_unlock(&AS->lock); |
|
return 1; |
} |
|
/** Install address space on CPU. |
* |
* @param as Address space. |
*/ |
void as_install(as_t *as) |
{ |
ipl_t ipl; |
|
ipl = interrupts_disable(); |
spinlock_lock(&as->lock); |
ASSERT(as->ptl0); |
SET_PTL0_ADDRESS(as->ptl0); |
spinlock_unlock(&as->lock); |
interrupts_restore(ipl); |
|
/* |
* Perform architecture-specific steps. |
* (e.g. invalidate TLB, install ASID etc.) |
*/ |
as_install_arch(as); |
|
AS = as; |
} |