/*
* Copyright (C) 2001-2005 Jakub Jermar
* Copyright (C) 2005 Sergey Bondari
* 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.
*/
/*
* Locking order
*
* In order to access particular zone, the process must first lock
* the zones.lock, then lock the zone and then unlock the zones.lock.
* This insures, that we can fiddle with the zones in runtime without
* affecting the processes.
*
*/
#include <typedefs.h>
#include <arch/types.h>
#include <mm/frame.h>
#include <mm/as.h>
#include <panic.h>
#include <debug.h>
#include <adt/list.h>
#include <synch/spinlock.h>
#include <arch/asm.h>
#include <arch.h>
#include <print.h>
#include <align.h>
#include <mm/slab.h>
typedef struct {
count_t refcount; /**< tracking of shared frames */
__u8 buddy_order; /**< buddy system block order */
link_t buddy_link; /**< link to the next free block inside one order */
void *parent; /**< If allocated by slab, this points there */
}frame_t;
typedef struct {
SPINLOCK_DECLARE(lock); /**< this lock protects everything below */
pfn_t base; /**< frame_no of the first frame in the frames array */
count_t count; /**< Size of zone */
frame_t *frames; /**< array of frame_t structures in this zone */
count_t free_count; /**< number of free frame_t structures */
count_t busy_count; /**< number of busy frame_t structures */
buddy_system_t * buddy_system; /**< buddy system for the zone */
int flags;
}zone_t;
/*
* The zoneinfo.lock must be locked when accessing zoneinfo structure.
* Some of the attributes in zone_t structures are 'read-only'
*/
struct {
SPINLOCK_DECLARE(lock);
int count;
zone_t *info[ZONES_MAX];
}zones;
/*********************************/
/* Helper functions */
static inline index_t frame_index(zone_t *zone, frame_t *frame)
{
return (index_t)(frame - zone->frames);
}
static inline index_t frame_index_abs(zone_t *zone, frame_t *frame)
{
return (index_t)(frame - zone->frames) + zone->base;
}
static inline int frame_index_valid(zone_t *zone, index_t index)
{
return index >= 0 && index < zone->count;
}
/** Compute pfn_t from frame_t pointer & zone pointer */
static index_t make_frame_index(zone_t *zone, frame_t *frame)
{
return frame - zone->frames;
}
/** Initialize frame structure
*
* Initialize frame structure.
*
* @param frame Frame structure to be initialized.
*/
static void frame_initialize(frame_t *frame)
{
frame->refcount = 1;
frame->buddy_order = 0;
}
/*************************************/
/* Zoneinfo functions */
/**
* Insert-sort zone into zones list
*/
static void zones_add_zone(zone_t *zone)
{
int i;
spinlock_lock(&zones.lock);
/* Try to merge */
if (zone->flags & ZONE_JOIN) {
for (i=0; i < zones.count; i++) {
spinlock_lock(&zones.info[i]->lock);
/* Join forward, join backward */
panic("Not implemented");
spinlock_unlock(&zones.info[i]->lock);
}
spinlock_unlock(&zones.lock);
} else {
if (zones.count+1 == ZONES_MAX)
panic("Maximum zone(%d) count exceeded.", ZONES_MAX);
zones.info[zones.count++] = zone;
}
spinlock_unlock(&zones.lock);
}
/**
* Try to find a zone where can we find the frame
*
* @param hint Start searching in zone 'hint'
* @param lock Lock zone if true
*
* Assume interrupts disable
*/
static zone_t * find_zone_and_lock(pfn_t frame, int *pzone)
{
int i;
int hint = pzone ? *pzone : 0;
zone_t *z;
spinlock_lock(&zones.lock);
if (hint >= zones.count || hint < 0)
hint = 0;
i = hint;
do {
z = zones.info[i];
spinlock_lock(&z->lock);
if (z->base <= frame && z->base + z->count > frame) {
spinlock_unlock(&zones.lock); /* Unlock the global lock */
if (pzone)
*pzone = i;
return z;
}
spinlock_unlock(&z->lock);
i++;
if (i >= zones.count)
i = 0;
} while(i != hint);
spinlock_unlock(&zones.lock);
return NULL;
}
/**
* Find AND LOCK zone that can allocate order frames
*
* Assume interrupts are disabled!!
*
* @param pzone Pointer to preferred zone or NULL, on return contains zone number
*/
static zone_t * find_free_zone_lock(__u8 order, int *pzone)
{
int i;
zone_t *z;
int hint = pzone ? *pzone : 0;
spinlock_lock(&zones.lock);
if (hint >= zones.count)
hint = 0;
i = hint;
do {
z = zones.info[i];
spinlock_lock(&z->lock);
/* Check if the zone has 2^order frames area available */
if (buddy_system_can_alloc(z->buddy_system, order)) {
spinlock_unlock(&zones.lock);
if (pzone)
*pzone = i;
return z;
}
spinlock_unlock(&z->lock);
if (++i >= zones.count)
i = 0;
} while(i != hint);
spinlock_unlock(&zones.lock);
return NULL;
}
/********************************************/
/* Buddy system functions */
/** Buddy system find_block implementation
*
* Find block that is parent of current list.
* That means go to lower addresses, until such block is found
*
* @param order - Order of parent must be different then this parameter!!
*/
static link_t *zone_buddy_find_block(buddy_system_t *b, link_t *child,
__u8 order)
{
frame_t * frame;
zone_t * zone;
index_t index;
frame = list_get_instance(child, frame_t, buddy_link);
zone = (zone_t *) b->data;
index = frame_index(zone, frame);
do {
if (zone->frames[index].buddy_order != order) {
return &zone->frames[index].buddy_link;
}
} while(index-- > 0);
return NULL;
}
/** 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
*/
static link_t * zone_buddy_find_buddy(buddy_system_t *b, link_t * block)
{
frame_t * frame;
zone_t * zone;
index_t index;
bool is_left, is_right;
frame = list_get_instance(block, frame_t, buddy_link);
zone = (zone_t *) b->data;
ASSERT(IS_BUDDY_ORDER_OK(frame_index_abs(zone, frame), frame->buddy_order));
is_left = IS_BUDDY_LEFT_BLOCK_ABS(zone, frame);
is_right = IS_BUDDY_RIGHT_BLOCK_ABS(zone, frame);
ASSERT(is_left ^ is_right);
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
*/
static 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)
*/
static 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
*/
static 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
*/
static __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
*
*/
static 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;
}
/** Buddy system mark_available implementation
*
* @param b Buddy system
* @param block Buddy system block
*
*/
static void zone_buddy_mark_available(buddy_system_t *b, link_t * block) {
frame_t * frame;
frame = list_get_instance(block, frame_t, buddy_link);
frame->refcount = 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,
.mark_available = zone_buddy_mark_available,
.find_block = zone_buddy_find_block
};
/*************************************/
/* Zone functions */
/** Allocate frame in particular zone
*
* Assume zone is locked
*
* @return Frame index in zone
*/
static pfn_t zone_frame_alloc(zone_t *zone,__u8 order, int flags, int *status)
{
pfn_t v;
link_t *tmp;
frame_t *frame;
/* 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 = make_frame_index(zone, frame);
return v;
}
/** Free frame from zone
*
* Assume zone is locked
*/
static void zone_frame_free(zone_t *zone, index_t frame_idx)
{
frame_t *frame;
__u8 order;
frame = &zone->frames[frame_idx];
/* remember frame order */
order = frame->buddy_order;
ASSERT(frame->refcount);
if (!--frame->refcount) {
buddy_system_free(zone->buddy_system, &frame->buddy_link);
}
/* Update zone information. */
zone->free_count += (1 << order);
zone->busy_count -= (1 << order);
}
/** Return frame from zone */
static frame_t * zone_get_frame(zone_t *zone, index_t frame_idx)
{
ASSERT(frame_idx < zone->count);
return &zone->frames[frame_idx];
}
/** Mark frame in zone unavailable to allocation */
static void zone_mark_unavailable(zone_t *zone, index_t frame_idx)
{
frame_t *frame;
link_t *link;
frame = zone_get_frame(zone, frame_idx);
link = buddy_system_alloc_block(zone->buddy_system,
&frame->buddy_link);
ASSERT(link);
zone->free_count--;
}
/** 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 conffram Address of configuration frame
* @param flags Zone flags.
*
* @return Initialized zone.
*/
static zone_t * zone_construct(pfn_t start, count_t count,
zone_t *z, int flags)
{
int i;
__u8 max_order;
spinlock_initialize(&z->lock, "zone_lock");
z->base = start;
z->count = count;
z->flags = flags;
z->free_count = count;
z->busy_count = 0;
/*
* Compute order for buddy system, initialize
*/
for (max_order = 0; count >> max_order; max_order++)
;
z->buddy_system = (buddy_system_t *)&z[1];
buddy_system_create(z->buddy_system, max_order,
&zone_buddy_system_operations,
(void *) z);
/* Allocate frames _after_ the conframe */
/* Check sizes */
z->frames = (frame_t *)((void *)z->buddy_system+buddy_conf_size(max_order));
for (i = 0; i<count; i++) {
frame_initialize(&z->frames[i]);
}
/* Stuffing frames */
for (i = 0; i < count; i++) {
z->frames[i].refcount = 0;
buddy_system_free(z->buddy_system, &z->frames[i].buddy_link);
}
return z;
}
/** Compute configuration data size for zone */
__address zone_conf_size(pfn_t start, count_t count)
{
int size = sizeof(zone_t) + count*sizeof(frame_t);
int max_order;
for (max_order = 0; count >> max_order; max_order++)
;
size += buddy_conf_size(max_order);
return size;
}
/** Create and add zone to system
*
* @param confframe Where configuration frame is supposed to be.
* Always check, that we will not disturb the kernel and possibly init.
* If confframe is given _outside_ this zone, it is expected,
* that the area is already marked BUSY and big enough
* to contain zone_conf_size() amount of data
*/
void zone_create(pfn_t start, count_t count, pfn_t confframe, int flags)
{
zone_t *z;
__address addr,endaddr;
count_t confcount;
int i;
/* Theoretically we could have here 0, practically make sure
* nobody tries to do that. If some platform requires, remove
* the assert
*/
ASSERT(confframe);
/* If conframe is supposed to be inside our zone, then make sure
* it does not span kernel & init
*/
confcount = SIZE2FRAMES(zone_conf_size(start,count));
if (confframe >= start && confframe < start+count) {
for (;confframe < start+count;confframe++) {
addr = PFN2ADDR(confframe);
endaddr = PFN2ADDR (confframe + confcount);
if (overlaps(addr, endaddr, KA2PA(config.base),
KA2PA(config.base+config.kernel_size)))
continue;
if (config.init_addr)
if (overlaps(addr,endaddr,
KA2PA(config.init_addr),
KA2PA(config.init_addr+config.init_size)))
continue;
break;
}
if (confframe >= start+count)
panic("Cannot find configuration data for zone.");
}
z = zone_construct(start, count, (zone_t *)PA2KA(PFN2ADDR(confframe)), flags);
zones_add_zone(z);
/* If confdata in zone, mark as unavailable */
if (confframe >= start && confframe < start+count)
for (i=confframe; i<confframe+confcount; i++) {
zone_mark_unavailable(z, i - z->base);
}
}
/***************************************/
/* Frame functions */
/** Set parent of frame */
void frame_set_parent(pfn_t pfn, void *data, int hint)
{
zone_t *zone = find_zone_and_lock(pfn, &hint);
ASSERT(zone);
zone_get_frame(zone, pfn-zone->base)->parent = data;
spinlock_unlock(&zone->lock);
}
void * frame_get_parent(pfn_t pfn, int hint)
{
zone_t *zone = find_zone_and_lock(pfn, &hint);
void *res;
ASSERT(zone);
res = zone_get_frame(zone, pfn - zone->base)->parent;
spinlock_unlock(&zone->lock);
return res;
}
/** 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.
* @param pzone Preferred zone
*
* @return Allocated frame.
*/
pfn_t frame_alloc_generic(__u8 order, int flags, int * status, int *pzone)
{
ipl_t ipl;
int freed;
pfn_t v;
zone_t *zone;
loop:
ipl = interrupts_disable();
/*
* First, find suitable frame zone.
*/
zone = find_free_zone_lock(order,pzone);
/* If no memory, reclaim some slab memory,
if it does not help, reclaim all */
if (!zone && !(flags & FRAME_NO_RECLAIM)) {
freed = slab_reclaim(0);
if (freed)
zone = find_free_zone_lock(order,pzone);
if (!zone) {
freed = slab_reclaim(SLAB_RECLAIM_ALL);
if (freed)
zone = find_free_zone_lock(order,pzone);
}
}
if (!zone) {
if (flags & FRAME_PANIC)
panic("Can't allocate frame.\n");
/*
* TODO: Sleep until frames are available again.
*/
interrupts_restore(ipl);
if (flags & FRAME_ATOMIC) {
ASSERT(status != NULL);
if (status)
*status = FRAME_NO_MEMORY;
return NULL;
}
panic("Sleep not implemented.\n");
goto loop;
}
v = zone_frame_alloc(zone,order,flags,status);
v += zone->base;
spinlock_unlock(&zone->lock);
interrupts_restore(ipl);
if (status)
*status = FRAME_OK;
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 frame Frame no to be freed.
*/
void frame_free(pfn_t pfn)
{
ipl_t ipl;
zone_t *zone;
ipl = interrupts_disable();
/*
* First, find host frame zone for addr.
*/
zone = find_zone_and_lock(pfn,NULL);
ASSERT(zone);
zone_frame_free(zone, pfn-zone->base);
spinlock_unlock(&zone->lock);
interrupts_restore(ipl);
}
/** Mark given range unavailable in frame zones */
void frame_mark_unavailable(pfn_t start, count_t count)
{
int i;
zone_t *zone;
int prefzone = 0;
for (i=0; i<count; i++) {
zone = find_zone_and_lock(start+i,&prefzone);
if (!zone) /* PFN not found */
continue;
zone_mark_unavailable(zone, start+i-zone->base);
spinlock_unlock(&zone->lock);
}
}
/** Initialize physical memory management
*
* Initialize physical memory managemnt.
*/
void frame_init(void)
{
if (config.cpu_active == 1) {
zones.count = 0;
spinlock_initialize(&zones.lock,"zones_glob_lock");
}
/* Tell the architecture to create some memory */
frame_arch_init();
if (config.cpu_active == 1) {
frame_mark_unavailable(ADDR2PFN(KA2PA(config.base)),
SIZE2FRAMES(config.kernel_size));
if (config.init_size > 0)
frame_mark_unavailable(ADDR2PFN(KA2PA(config.init_addr)),
SIZE2FRAMES(config.init_size));
}
}
/** Prints list of zones
*
*/
void zone_print_list(void) {
zone_t *zone = NULL;
int i;
ipl_t ipl;
ipl = interrupts_disable();
spinlock_lock(&zones.lock);
printf("Base address\tFree Frames\tBusy Frames\n"); printf("------------\t-----------\t-----------\n"); for (i=0;i<zones.count;i++) {
zone = zones.info[i];
spinlock_lock(&zone->lock);
printf("%L\t%d\t\t%d\n",PFN2ADDR
(zone
->base
), zone->free_count, zone->busy_count);
spinlock_unlock(&zone->lock);
}
spinlock_unlock(&zones.lock);
interrupts_restore(ipl);
}
/** Prints zone details
*
* @param base Zone base address
*/
void zone_print_one(int znum) {
zone_t *zone = NULL;
ipl_t ipl;
ipl = interrupts_disable();
spinlock_lock(&zones.lock);
if (znum >= zones.count || znum < 0) {
printf("Zone number out of bounds.\n"); spinlock_unlock(&zones.lock);
interrupts_restore(ipl);
return;
}
zone = zones.info[znum];
spinlock_lock(&zone->lock);
printf("Memory zone information\n\n"); printf("Zone base address: %P\n", PFN2ADDR
(zone
->base
)); printf("Zone size: %d frames (%dK)\n", zone
->count
, ((zone
->count
) * FRAME_SIZE
) >> 10); printf("Allocated space: %d frames (%dK)\n", zone
->busy_count
, (zone
->busy_count
* FRAME_SIZE
) >> 10); printf("Available space: %d (%dK)\n", zone
->free_count
, (zone
->free_count
* FRAME_SIZE
) >> 10);
printf("\nBuddy allocator structures:\n\n"); buddy_system_structure_print(zone->buddy_system, FRAME_SIZE);
spinlock_unlock(&zone->lock);
spinlock_unlock(&zones.lock);
interrupts_restore(ipl);
}