/*
* 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.
*/
#include <typedefs.h>
#include <arch/types.h>
#include <mm/heap.h>
#include <mm/frame.h>
#include <mm/vm.h>
#include <panic.h>
#include <debug.h>
#include <list.h>
#include <synch/spinlock.h>
#include <arch/asm.h>
#include <arch.h>
#include <print.h>
#include <align.h>
spinlock_t zone_head_lock; /**< this lock protects zone_head list */
link_t zone_head; /**< list of all zones in the system */
/** Blacklist containing non-available areas of memory.
*
* This blacklist is used to exclude frames that cannot be allocated
* (e.g. kernel memory) from available memory map.
*/
region_t zone_blacklist[ZONE_BLACKLIST_SIZE];
count_t zone_blacklist_count = 0;
static struct buddy_system_operations zone_buddy_system_operations = {
.find_buddy = zone_buddy_find_buddy,
.bisect = zone_buddy_bisect,
.coalesce = zone_buddy_coalesce,
.set_order = zone_buddy_set_order,
.get_order = zone_buddy_get_order,
.mark_busy = zone_buddy_mark_busy,
};
/** Initialize physical memory management
*
* Initialize physical memory managemnt.
*/
void frame_init(void)
{
if (config.cpu_active == 1) {
zone_init();
frame_region_not_free(KA2PA(config.base), config.kernel_size);
}
frame_arch_init();
}
/** Allocate power-of-two frames of physical memory.
*
* @param flags Flags for host zone selection and address processing.
* @param order Allocate exactly 2^order frames.
*
* @return Allocated frame.
*/
__address frame_alloc(int flags, __u8 order)
{
ipl_t ipl;
link_t *cur, *tmp;
zone_t *z;
zone_t *zone = NULL;
frame_t *frame = NULL;
__address v;
loop:
ipl = interrupts_disable();
spinlock_lock(&zone_head_lock);
/*
* First, find suitable frame zone.
*/
for (cur = zone_head.next; cur != &zone_head; cur = cur->next) {
z = list_get_instance(cur, zone_t, link);
spinlock_lock(&z->lock);
/* Check if the zone has 2^order frames area available */
if (buddy_system_can_alloc(z->buddy_system, order)) {
zone = z;
break;
}
spinlock_unlock(&z->lock);
}
if (!zone) {
if (flags & FRAME_PANIC)
panic("Can't allocate frame.\n");
/*
* TODO: Sleep until frames are available again.
*/
spinlock_unlock(&zone_head_lock);
interrupts_restore(ipl);
panic("Sleep not implemented.\n");
goto loop;
}
/* Allocate frames from zone buddy system */
tmp = buddy_system_alloc(zone->buddy_system, order);
ASSERT(tmp);
/* Update zone information. */
zone->free_count -= (1 << order);
zone->busy_count += (1 << order);
/* Frame will be actually a first frame of the block. */
frame = list_get_instance(tmp, frame_t, buddy_link);
/* get frame address */
v = FRAME2ADDR(zone, frame);
spinlock_unlock(&zone->lock);
spinlock_unlock(&zone_head_lock);
interrupts_restore(ipl);
if (flags & FRAME_KA)
v = PA2KA(v);
return v;
}
/** Free a frame.
*
* Find respective frame structrue for supplied addr.
* Decrement frame reference count.
* If it drops to zero, move the frame structure to free list.
*
* @param addr Address of the frame to be freed. It must be a multiple of FRAME_SIZE.
*/
void frame_free(__address addr)
{
ipl_t ipl;
link_t *cur;
zone_t *z;
zone_t *zone = NULL;
frame_t *frame;
ASSERT(addr % FRAME_SIZE == 0);
ipl = interrupts_disable();
spinlock_lock(&zone_head_lock);
/*
* First, find host frame zone for addr.
*/
for (cur = zone_head.next; cur != &zone_head; cur = cur->next) {
z = list_get_instance(cur, zone_t, link);
spinlock_lock(&z->lock);
if (IS_KA(addr))
addr = KA2PA(addr);
/*
* Check if addr belongs to z.
*/
if ((addr >= z->base) && (addr <= z->base + (z->free_count + z->busy_count) * FRAME_SIZE)) {
zone = z;
break;
}
spinlock_unlock(&z->lock);
}
ASSERT(zone != NULL);
frame = ADDR2FRAME(zone, addr);
ASSERT(frame->refcount);
if (!--frame->refcount) {
buddy_system_free(zone->buddy_system, &frame->buddy_link);
}
/* Update zone information. */
zone->free_count += (1 << frame->buddy_order);
zone->busy_count -= (1 << frame->buddy_order);
spinlock_unlock(&zone->lock);
spinlock_unlock(&zone_head_lock);
interrupts_restore(ipl);
}
/** Mark frame region not free.
*
* Mark frame region not free.
*
* @param base Base address of non-available region.
* @param size Size of non-available region.
*/
void frame_region_not_free(__address base, size_t size)
{
index_t index;
index = zone_blacklist_count++;
/* Force base to the nearest lower address frame boundary. */
base &= ~(FRAME_SIZE - 1);
/* Align size to frame boundary. */
size = ALIGN(size, FRAME_SIZE);
ASSERT(zone_blacklist_count <= ZONE_BLACKLIST_SIZE);
zone_blacklist[index].base = base;
zone_blacklist[index].size = size;
}
/** Initialize zonekeeping
*
* Initialize zonekeeping.
*/
void zone_init(void)
{
spinlock_initialize(&zone_head_lock, "zone_head_lock");
list_initialize(&zone_head);
}
/** Create frame zones in region of available memory.
*
* Avoid any black listed areas of non-available memory.
* Assume that the black listed areas cannot overlap
* one another or cross available memory region boundaries.
*
* @param base Base address of available memory region.
* @param size Size of the region.
*/
void zone_create_in_region(__address base, size_t size) {
int i;
zone_t * z;
__address s;
size_t sz;
ASSERT(base % FRAME_SIZE == 0);
ASSERT(size % FRAME_SIZE == 0);
if (!size)
return;
for (i = 0; i < zone_blacklist_count; i++) {
if (zone_blacklist[i].base >= base && zone_blacklist[i].base < base + size) {
s = base; sz = zone_blacklist[i].base - base;
ASSERT(base != s || sz != size);
zone_create_in_region(s, sz);
s = zone_blacklist[i].base + zone_blacklist[i].size;
sz = (base + size) - (zone_blacklist[i].base + zone_blacklist[i].size);
ASSERT(base != s || sz != size);
zone_create_in_region(s, sz);
return;
}
}
z = zone_create(base, size, 0);
if (!z) {
panic("Cannot allocate zone (%dB).\n", size);
}
zone_attach(z);
}
/** Create frame zone
*
* Create new frame zone.
*
* @param start Physical address of the first frame within the zone.
* @param size Size of the zone. Must be a multiple of FRAME_SIZE.
* @param flags Zone flags.
*
* @return Initialized zone.
*/
zone_t * zone_create(__address start, size_t size, int flags)
{
zone_t *z;
count_t cnt;
int i;
__u8 max_order;
ASSERT(start % FRAME_SIZE == 0);
ASSERT(size % FRAME_SIZE == 0);
cnt = size / FRAME_SIZE;
z = (zone_t *) early_malloc(sizeof(zone_t));
if (z) {
link_initialize(&z->link);
spinlock_initialize(&z->lock, "zone_lock");
z->base = start;
z->flags = flags;
z->free_count = cnt;
z->busy_count = 0;
z->frames = (frame_t *) early_malloc(cnt * sizeof(frame_t));
if (!z->frames) {
early_free(z);
return NULL;
}
for (i = 0; i<cnt; i++) {
frame_initialize(&z->frames[i], z);
}
/*
* Create buddy system for the zone
*/
for (max_order = 0; cnt >> max_order; max_order++)
;
z->buddy_system = buddy_system_create(max_order, &zone_buddy_system_operations, (void *) z);
/* Stuffing frames */
for (i = 0; i<cnt; i++) {
z->frames[i].refcount = 0;
buddy_system_free(z->buddy_system, &z->frames[i].buddy_link);
}
}
return z;
}
/** Attach frame zone
*
* Attach frame zone to zone list.
*
* @param zone Zone to be attached.
*/
void zone_attach(zone_t *zone)
{
ipl_t ipl;
ipl = interrupts_disable();
spinlock_lock(&zone_head_lock);
list_append(&zone->link, &zone_head);
spinlock_unlock(&zone_head_lock);
interrupts_restore(ipl);
}
/** Initialize frame structure
*
* Initialize frame structure.
*
* @param frame Frame structure to be initialized.
* @param zone Host frame zone.
*/
void frame_initialize(frame_t *frame, zone_t *zone)
{
frame->refcount = 1;
frame->buddy_order = 0;
}
/** Buddy system find_buddy implementation
*
* @param b Buddy system.
* @param block Block for which buddy should be found
*
* @return Buddy for given block if found
*/
link_t * zone_buddy_find_buddy(buddy_system_t *b, link_t * block) {
frame_t * frame;
zone_t * zone;
count_t index;
bool is_left, is_right;
frame = list_get_instance(block, frame_t, buddy_link);
zone = (zone_t *) b->data;
is_left = IS_BUDDY_LEFT_BLOCK(zone, frame);
is_right = !is_left;
/*
* test left buddy
*/
if (is_left) {
index = (FRAME_INDEX(zone, frame)) + (1 << frame->buddy_order);
} else if (is_right) {
index = (FRAME_INDEX(zone, frame)) - (1 << frame->buddy_order);
}
if (FRAME_INDEX_VALID(zone, index)) {
if ( zone->frames[index].buddy_order == frame->buddy_order &&
zone->frames[index].refcount == 0) {
return &zone->frames[index].buddy_link;
}
}
return NULL;
}
/** Buddy system bisect implementation
*
* @param b Buddy system.
* @param block Block to bisect
*
* @return right block
*/
link_t * zone_buddy_bisect(buddy_system_t *b, link_t * block) {
frame_t * frame_l, * frame_r;
frame_l = list_get_instance(block, frame_t, buddy_link);
frame_r = (frame_l + (1 << (frame_l->buddy_order - 1)));
return &frame_r->buddy_link;
}
/** Buddy system coalesce implementation
*
* @param b Buddy system.
* @param block_1 First block
* @param block_2 First block's buddy
*
* @return Coalesced block (actually block that represents lower address)
*/
link_t * zone_buddy_coalesce(buddy_system_t *b, link_t * block_1, link_t * block_2) {
frame_t * frame1, * frame2;
frame1 = list_get_instance(block_1, frame_t, buddy_link);
frame2 = list_get_instance(block_2, frame_t, buddy_link);
return frame1 < frame2 ? block_1 : block_2;
}
/** Buddy system set_order implementation
*
* @param b Buddy system.
* @param block Buddy system block
* @param order Order to set
*/
void zone_buddy_set_order(buddy_system_t *b, link_t * block, __u8 order) {
frame_t * frame;
frame = list_get_instance(block, frame_t, buddy_link);
frame->buddy_order = order;
}
/** Buddy system get_order implementation
*
* @param b Buddy system.
* @param block Buddy system block
*
* @return Order of block
*/
__u8 zone_buddy_get_order(buddy_system_t *b, link_t * block) {
frame_t * frame;
frame = list_get_instance(block, frame_t, buddy_link);
return frame->buddy_order;
}
/** Buddy system mark_busy implementation
*
* @param b Buddy system
* @param block Buddy system block
*
*/
void zone_buddy_mark_busy(buddy_system_t *b, link_t * block) {
frame_t * frame;
frame = list_get_instance(block, frame_t, buddy_link);
frame->refcount = 1;
}