Rev 3207 | Rev 3972 | Go to most recent revision | Blame | Compare with Previous | Last modification | View Log | Download | RSS feed
/*
* 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.
*/
/** @addtogroup genericmm
* @{
*/
/**
* @file
* @brief Physical frame allocator.
*
* This file contains the physical frame allocator and memory zone management.
* The frame allocator is built on top of the buddy allocator.
*
* @see buddy.c
*/
/*
* 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 <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 <synch/mutex.h>
#include <synch/condvar.h>
#include <arch/asm.h>
#include <arch.h>
#include <print.h>
#include <align.h>
#include <mm/slab.h>
#include <bitops.h>
#include <macros.h>
#include <config.h>
typedef struct {
count_t refcount; /**< tracking of shared frames */
uint8_t 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'
*/
typedef struct {
SPINLOCK_DECLARE(lock);
unsigned int count;
zone_t *info[ZONES_MAX];
} zones_t;
static zones_t zones;
/*
* Synchronization primitives used to sleep when there is no memory
* available.
*/
mutex_t mem_avail_mtx;
condvar_t mem_avail_cv;
unsigned long mem_avail_frames = 0; /**< Number of available frames. */
unsigned long mem_avail_gen = 0; /**< Generation counter. */
/********************/
/* 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 < 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.
*
* @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.
*
* @param newzone New zone to be inserted into zone list.
* @return Zone number on success, -1 on error.
*/
static int zones_add_zone(zone_t *newzone)
{
unsigned int i, j;
ipl_t ipl;
zone_t *z;
ipl = interrupts_disable();
spinlock_lock(&zones.lock);
/* Try to merge */
if (zones.count + 1 == ZONES_MAX) {
printf("Maximum zone count %u exceeded!\n", ZONES_MAX);
spinlock_unlock(&zones.lock);
interrupts_restore(ipl);
return -1;
}
for (i = 0; i < zones.count; i++) {
/* Check for overflow */
z = zones.info[i];
if (overlaps(newzone->base, newzone->count, z->base,
z->count)) {
printf("Zones overlap!\n");
return -1;
}
if (newzone->base < z->base)
break;
}
/* Move other zones up */
for (j = i; j < zones.count; j++)
zones.info[j + 1] = zones.info[j];
zones.info[i] = newzone;
zones.count++;
spinlock_unlock(&zones.lock);
interrupts_restore(ipl);
return i;
}
/** Try to find a zone where can we find the frame.
*
* Assume interrupts are disabled.
*
* @param frame Frame number contained in zone.
* @param pzone If not null, it is used as zone hint. Zone index is
* filled into the variable on success.
* @return Pointer to locked zone containing frame.
*/
static zone_t *find_zone_and_lock(pfn_t frame, unsigned int *pzone)
{
unsigned int i;
unsigned int hint = pzone ? *pzone : 0;
zone_t *z;
spinlock_lock(&zones.lock);
if (hint >= zones.count)
hint = 0;
i = hint;
do {
z = zones.info[i];
spinlock_lock(&z->lock);
if (z->base <= frame && z->base + z->count > frame) {
/* Unlock the global lock */
spinlock_unlock(&zones.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;
}
/** @return True if zone can allocate specified order */
static int zone_can_alloc(zone_t *z, uint8_t order)
{
return buddy_system_can_alloc(z->buddy_system, order);
}
/** Find and lock zone that can allocate order frames.
*
* Assume interrupts are disabled.
*
* @param order Size (2^order) of free space we are trying to find.
* @param flags Required flags of the target zone.
* @param pzone Pointer to preferred zone or NULL, on return contains
* zone number.
*/
static zone_t *
find_free_zone_and_lock(uint8_t order, int flags, unsigned int *pzone)
{
unsigned int i;
zone_t *z;
unsigned int hint = pzone ? *pzone : 0;
/* Mask off flags that are not applicable. */
flags &= FRAME_LOW_4_GiB;
spinlock_lock(&zones.lock);
if (hint >= zones.count)
hint = 0;
i = hint;
do {
z = zones.info[i];
spinlock_lock(&z->lock);
/*
* Check whether the zone meets the search criteria.
*/
if ((z->flags & flags) == flags) {
/*
* Check if the zone has 2^order frames area available.
*/
if (zone_can_alloc(z, 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,
uint8_t 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,
uint8_t 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 uint8_t 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 buddy_system_operations_t 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.
* Panics if allocation is impossible.
*
* @param zone Zone to allocate from.
* @param order Allocate exactly 2^order frames.
*
* @return Frame index in zone.
*
*/
static pfn_t zone_frame_alloc(zone_t *zone, uint8_t order)
{
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.
*
* @param zone Pointer to zone from which the frame is to be freed.
* @param frame_idx Frame index relative to zone.
*/
static void zone_frame_free(zone_t *zone, index_t frame_idx)
{
frame_t *frame;
uint8_t 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);
if (frame->refcount)
return;
link = buddy_system_alloc_block(zone->buddy_system,
&frame->buddy_link);
ASSERT(link);
zone->free_count--;
mutex_lock(&mem_avail_mtx);
mem_avail_frames--;
mutex_unlock(&mem_avail_mtx);
}
/** Join two zones.
*
* Expect zone_t *z to point to space at least zone_conf_size large.
*
* Assume z1 & z2 are locked.
*
* @param z Target zone structure pointer.
* @param z1 Zone to merge.
* @param z2 Zone to merge.
*/
static void _zone_merge(zone_t *z, zone_t *z1, zone_t *z2)
{
uint8_t max_order;
unsigned int i;
int z2idx;
pfn_t frame_idx;
frame_t *frame;
ASSERT(!overlaps(z1->base, z1->count, z2->base, z2->count));
ASSERT(z1->base < z2->base);
spinlock_initialize(&z->lock, "zone_lock");
z->base = z1->base;
z->count = z2->base + z2->count - z1->base;
z->flags = z1->flags & z2->flags;
z->free_count = z1->free_count + z2->free_count;
z->busy_count = z1->busy_count + z2->busy_count;
max_order = fnzb(z->count);
z->buddy_system = (buddy_system_t *) &z[1];
buddy_system_create(z->buddy_system, max_order,
&zone_buddy_system_operations, (void *) z);
z->frames = (frame_t *)((uint8_t *) z->buddy_system +
buddy_conf_size(max_order));
for (i = 0; i < z->count; i++) {
/* This marks all frames busy */
frame_initialize(&z->frames[i]);
}
/* Copy frames from both zones to preserve full frame orders,
* parents etc. Set all free frames with refcount=0 to 1, because
* we add all free frames to buddy allocator later again, clear
* order to 0. Don't set busy frames with refcount=0, as they
* will not be reallocated during merge and it would make later
* problems with allocation/free.
*/
for (i = 0; i < z1->count; i++)
z->frames[i] = z1->frames[i];
for (i = 0; i < z2->count; i++) {
z2idx = i + (z2->base - z1->base);
z->frames[z2idx] = z2->frames[i];
}
i = 0;
while (i < z->count) {
if (z->frames[i].refcount) {
/* skip busy frames */
i += 1 << z->frames[i].buddy_order;
} else { /* Free frames, set refcount=1 */
/* All free frames have refcount=0, we need not
* to check the order */
z->frames[i].refcount = 1;
z->frames[i].buddy_order = 0;
i++;
}
}
/* Add free blocks from the 2 original zones */
while (zone_can_alloc(z1, 0)) {
frame_idx = zone_frame_alloc(z1, 0);
frame = &z->frames[frame_idx];
frame->refcount = 0;
buddy_system_free(z->buddy_system, &frame->buddy_link);
}
while (zone_can_alloc(z2, 0)) {
frame_idx = zone_frame_alloc(z2, 0);
frame = &z->frames[frame_idx + (z2->base - z1->base)];
frame->refcount = 0;
buddy_system_free(z->buddy_system, &frame->buddy_link);
}
}
/** Return old configuration frames into the zone.
*
* We have several cases
* - the conf. data is outside of zone -> exit, shall we call frame_free??
* - the conf. data was created by zone_create or
* updated with reduce_region -> free every frame
*
* @param newzone The actual zone where freeing should occur.
* @param oldzone Pointer to old zone configuration data that should
* be freed from new zone.
*/
static void return_config_frames(zone_t *newzone, zone_t *oldzone)
{
pfn_t pfn;
frame_t *frame;
count_t cframes;
unsigned int i;
pfn = ADDR2PFN((uintptr_t)KA2PA(oldzone));
cframes = SIZE2FRAMES(zone_conf_size(oldzone->count));
if (pfn < newzone->base || pfn >= newzone->base + newzone->count)
return;
frame = &newzone->frames[pfn - newzone->base];
ASSERT(!frame->buddy_order);
for (i = 0; i < cframes; i++) {
newzone->busy_count++;
zone_frame_free(newzone, pfn+i-newzone->base);
}
}
/** Reduce allocated block to count of order 0 frames.
*
* The allocated block need 2^order frames of space. Reduce all frames
* in block to order 0 and free the unneeded frames. This means, that
* when freeing the previously allocated block starting with frame_idx,
* you have to free every frame.
*
* @param zone
* @param frame_idx Index to block.
* @param count Allocated space in block.
*/
static void zone_reduce_region(zone_t *zone, pfn_t frame_idx, count_t count)
{
count_t i;
uint8_t order;
frame_t *frame;
ASSERT(frame_idx + count < zone->count);
order = zone->frames[frame_idx].buddy_order;
ASSERT((count_t) (1 << order) >= count);
/* Reduce all blocks to order 0 */
for (i = 0; i < (count_t) (1 << order); i++) {
frame = &zone->frames[i + frame_idx];
frame->buddy_order = 0;
if (!frame->refcount)
frame->refcount = 1;
ASSERT(frame->refcount == 1);
}
/* Free unneeded frames */
for (i = count; i < (count_t) (1 << order); i++) {
zone_frame_free(zone, i + frame_idx);
}
}
/** Merge zones z1 and z2.
*
* - the zones must be 2 zones with no zone existing in between,
* which means that z2 = z1+1
*
* - When you create a new zone, the frame allocator configuration does
* not to be 2^order size. Once the allocator is running it is no longer
* possible, merged configuration data occupies more space :-/
*/
void zone_merge(unsigned int z1, unsigned int z2)
{
ipl_t ipl;
zone_t *zone1, *zone2, *newzone;
unsigned int cframes;
uint8_t order;
unsigned int i;
pfn_t pfn;
ipl = interrupts_disable();
spinlock_lock(&zones.lock);
if ((z1 >= zones.count) || (z2 >= zones.count))
goto errout;
/* We can join only 2 zones with none existing inbetween */
if (z2 - z1 != 1)
goto errout;
zone1 = zones.info[z1];
zone2 = zones.info[z2];
spinlock_lock(&zone1->lock);
spinlock_lock(&zone2->lock);
cframes = SIZE2FRAMES(zone_conf_size(zone2->base + zone2->count -
zone1->base));
if (cframes == 1)
order = 0;
else
order = fnzb(cframes - 1) + 1;
/* Allocate zonedata inside one of the zones */
if (zone_can_alloc(zone1, order))
pfn = zone1->base + zone_frame_alloc(zone1, order);
else if (zone_can_alloc(zone2, order))
pfn = zone2->base + zone_frame_alloc(zone2, order);
else
goto errout2;
newzone = (zone_t *) PA2KA(PFN2ADDR(pfn));
_zone_merge(newzone, zone1, zone2);
/* Free unneeded config frames */
zone_reduce_region(newzone, pfn - newzone->base, cframes);
/* Subtract zone information from busy frames */
newzone->busy_count -= cframes;
/* Replace existing zones in zoneinfo list */
zones.info[z1] = newzone;
for (i = z2 + 1; i < zones.count; i++)
zones.info[i - 1] = zones.info[i];
zones.count--;
/* Free old zone information */
return_config_frames(newzone, zone1);
return_config_frames(newzone, zone2);
errout2:
/* Nobody is allowed to enter to zone, so we are safe
* to touch the spinlocks last time */
spinlock_unlock(&zone1->lock);
spinlock_unlock(&zone2->lock);
errout:
spinlock_unlock(&zones.lock);
interrupts_restore(ipl);
}
/** Merge all zones into one big zone.
*
* It is reasonable to do this on systems whose bios reports parts in chunks,
* so that we could have 1 zone (it's faster).
*/
void zone_merge_all(void)
{
int count = zones.count;
while (zones.count > 1 && --count) {
zone_merge(0, 1);
break;
}
}
/** Create new frame zone.
*
* @param start Physical address of the first frame within the zone.
* @param count Count of frames in zone.
* @param z Address of configuration information of zone.
* @param flags Zone flags.
*
* @return Initialized zone.
*/
static void zone_construct(pfn_t start, count_t count, zone_t *z, int flags)
{
unsigned int i;
uint8_t max_order;
spinlock_initialize(&z->lock, "zone_lock");
z->base = start;
z->count = count;
/* Mask off flags that are calculated automatically. */
flags &= ~FRAME_LOW_4_GiB;
/* Determine calculated flags. */
if (z->base + count < (1ULL << (32 - FRAME_WIDTH))) /* 4 GiB */
flags |= FRAME_LOW_4_GiB;
z->flags = flags;
z->free_count = count;
z->busy_count = 0;
/*
* Compute order for buddy system, initialize
*/
max_order = fnzb(count);
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 *)((uint8_t *) 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);
}
}
/** Compute configuration data size for zone.
*
* @param count Size of zone in frames.
* @return Size of zone configuration info (in bytes).
*/
uintptr_t zone_conf_size(count_t count)
{
int size = sizeof(zone_t) + count * sizeof(frame_t);
int max_order;
max_order = fnzb(count);
size += buddy_conf_size(max_order);
return size;
}
/** Create and add zone to system.
*
* @param start First frame number (absolute).
* @param count Size of zone in frames.
* @param confframe Where configuration frames are supposed to be.
* Automatically checks, 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. If the confframe is
* inside the area, the zone free frame information is
* modified not to include it.
*
* @return Zone number or -1 on error.
*/
int zone_create(pfn_t start, count_t count, pfn_t confframe, int flags)
{
zone_t *z;
uintptr_t addr;
count_t confcount;
unsigned int i;
int znum;
/* 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(count));
if (confframe >= start && confframe < start + count) {
for (; confframe < start + count; confframe++) {
addr = PFN2ADDR(confframe);
if (overlaps(addr, PFN2ADDR(confcount),
KA2PA(config.base), config.kernel_size))
continue;
if (overlaps(addr, PFN2ADDR(confcount),
KA2PA(config.stack_base), config.stack_size))
continue;
bool overlap = false;
count_t i;
for (i = 0; i < init.cnt; i++)
if (overlaps(addr, PFN2ADDR(confcount),
KA2PA(init.tasks[i].addr),
init.tasks[i].size)) {
overlap = true;
break;
}
if (overlap)
continue;
break;
}
if (confframe >= start + count)
panic("Cannot find configuration data for zone.");
}
z = (zone_t *) PA2KA(PFN2ADDR(confframe));
zone_construct(start, count, z, flags);
znum = zones_add_zone(z);
if (znum == -1)
return -1;
mutex_lock(&mem_avail_mtx);
mem_avail_frames += count;
mutex_unlock(&mem_avail_mtx);
/* 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);
}
return znum;
}
/***************************************/
/* Frame functions */
/** Set parent of frame. */
void frame_set_parent(pfn_t pfn, void *data, unsigned 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, unsigned 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 order Allocate exactly 2^order frames.
* @param flags Flags for host zone selection and address processing.
* @param pzone Preferred zone.
*
* @return Physical address of the allocated frame.
*
*/
void *frame_alloc_generic(uint8_t order, int flags, unsigned int *pzone)
{
ipl_t ipl;
int freed;
pfn_t v;
zone_t *zone;
unsigned long gen = 0;
loop:
ipl = interrupts_disable();
/*
* First, find suitable frame zone.
*/
zone = find_free_zone_and_lock(order, flags, 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_and_lock(order, flags, pzone);
if (!zone) {
freed = slab_reclaim(SLAB_RECLAIM_ALL);
if (freed)
zone = find_free_zone_and_lock(order, flags,
pzone);
}
}
if (!zone) {
/*
* Sleep until some frames are available again.
*/
if (flags & FRAME_ATOMIC) {
interrupts_restore(ipl);
return 0;
}
#ifdef CONFIG_DEBUG
unsigned long avail;
mutex_lock(&mem_avail_mtx);
avail = mem_avail_frames;
mutex_unlock(&mem_avail_mtx);
printf("Thread %" PRIu64 " waiting for %u frames, "
"%u available.\n", THREAD->tid, 1ULL << order, avail);
#endif
mutex_lock(&mem_avail_mtx);
while ((mem_avail_frames < (1ULL << order)) ||
gen == mem_avail_gen)
condvar_wait(&mem_avail_cv, &mem_avail_mtx);
gen = mem_avail_gen;
mutex_unlock(&mem_avail_mtx);
#ifdef CONFIG_DEBUG
mutex_lock(&mem_avail_mtx);
avail = mem_avail_frames;
mutex_unlock(&mem_avail_mtx);
printf("Thread %" PRIu64 " woken up, %u frames available.\n",
THREAD->tid, avail);
#endif
interrupts_restore(ipl);
goto loop;
}
v = zone_frame_alloc(zone, order);
v += zone->base;
spinlock_unlock(&zone->lock);
mutex_lock(&mem_avail_mtx);
mem_avail_frames -= (1ULL << order);
mutex_unlock(&mem_avail_mtx);
interrupts_restore(ipl);
if (flags & FRAME_KA)
return (void *)PA2KA(PFN2ADDR(v));
return (void *)PFN2ADDR(v);
}
/** Free a frame.
*
* Find respective frame structure for supplied physical frame address.
* Decrement frame reference count.
* If it drops to zero, move the frame structure to free list.
*
* @param frame Physical Address of of the frame to be freed.
*/
void frame_free(uintptr_t frame)
{
ipl_t ipl;
zone_t *zone;
pfn_t pfn = ADDR2PFN(frame);
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);
/*
* Signal that some memory has been freed.
*/
mutex_lock(&mem_avail_mtx);
mem_avail_frames++;
mem_avail_gen++;
condvar_broadcast(&mem_avail_cv);
mutex_unlock(&mem_avail_mtx);
interrupts_restore(ipl);
}
/** Add reference to frame.
*
* Find respective frame structure for supplied PFN and
* increment frame reference count.
*
* @param pfn Frame number of the frame to be freed.
*/
void frame_reference_add(pfn_t pfn)
{
ipl_t ipl;
zone_t *zone;
frame_t *frame;
ipl = interrupts_disable();
/*
* First, find host frame zone for addr.
*/
zone = find_zone_and_lock(pfn, NULL);
ASSERT(zone);
frame = &zone->frames[pfn - zone->base];
frame->refcount++;
spinlock_unlock(&zone->lock);
interrupts_restore(ipl);
}
/** Mark given range unavailable in frame zones. */
void frame_mark_unavailable(pfn_t start, count_t count)
{
unsigned int i;
zone_t *zone;
unsigned 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. */
void frame_init(void)
{
if (config.cpu_active == 1) {
zones.count = 0;
spinlock_initialize(&zones.lock, "zones.lock");
mutex_initialize(&mem_avail_mtx, MUTEX_ACTIVE);
condvar_initialize(&mem_avail_cv);
}
/* 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));
frame_mark_unavailable(ADDR2PFN(KA2PA(config.stack_base)),
SIZE2FRAMES(config.stack_size));
count_t i;
for (i = 0; i < init.cnt; i++) {
pfn_t pfn = ADDR2PFN(KA2PA(init.tasks[i].addr));
frame_mark_unavailable(pfn,
SIZE2FRAMES(init.tasks[i].size));
}
if (ballocs.size)
frame_mark_unavailable(ADDR2PFN(KA2PA(ballocs.base)),
SIZE2FRAMES(ballocs.size));
/* Black list first frame, as allocating NULL would
* fail in some places */
frame_mark_unavailable(0, 1);
}
}
/** Return total size of all zones. */
uint64_t zone_total_size(void)
{
zone_t *zone = NULL;
unsigned int i;
ipl_t ipl;
uint64_t total = 0;
ipl = interrupts_disable();
spinlock_lock(&zones.lock);
for (i = 0; i < zones.count; i++) {
zone = zones.info[i];
spinlock_lock(&zone->lock);
total += (uint64_t) FRAMES2SIZE(zone->count);
spinlock_unlock(&zone->lock);
}
spinlock_unlock(&zones.lock);
interrupts_restore(ipl);
return total;
}
/** Prints list of zones. */
void zone_print_list(void)
{
zone_t *zone = NULL;
unsigned int i;
ipl_t ipl;
#ifdef __32_BITS__
printf("# base address free frames busy frames\n");
printf("-- ------------ ------------ ------------\n");
#endif
#ifdef __64_BITS__
printf("# base address free frames busy frames\n");
printf("-- -------------------- ------------ ------------\n");
#endif
/*
* Because printing may require allocation of memory, we may not hold
* the frame allocator locks when printing zone statistics. Therefore,
* we simply gather the statistics under the protection of the locks and
* print the statistics when the locks have been released.
*
* When someone adds/removes zones while we are printing the statistics,
* we may end up with inaccurate output (e.g. a zone being skipped from
* the listing).
*/
for (i = 0; ; i++) {
uintptr_t base;
count_t free_count;
count_t busy_count;
ipl = interrupts_disable();
spinlock_lock(&zones.lock);
if (i >= zones.count) {
spinlock_unlock(&zones.lock);
interrupts_restore(ipl);
break;
}
zone = zones.info[i];
spinlock_lock(&zone->lock);
base = PFN2ADDR(zone->base);
free_count = zone->free_count;
busy_count = zone->busy_count;
spinlock_unlock(&zone->lock);
spinlock_unlock(&zones.lock);
interrupts_restore(ipl);
#ifdef __32_BITS__
printf("%-2u %10p %12" PRIc " %12" PRIc "\n", i, base,
free_count, busy_count);
#endif
#ifdef __64_BITS__
printf("%-2u %18p %12" PRIc " %12" PRIc "\n", i, base,
free_count, busy_count);
#endif
}
}
/** Prints zone details.
*
* @param num Zone base address or zone number.
*/
void zone_print_one(unsigned int num)
{
zone_t *zone = NULL;
ipl_t ipl;
unsigned int i;
uintptr_t base;
count_t count;
count_t busy_count;
count_t free_count;
ipl = interrupts_disable();
spinlock_lock(&zones.lock);
for (i = 0; i < zones.count; i++) {
if ((i == num) || (PFN2ADDR(zones.info[i]->base) == num)) {
zone = zones.info[i];
break;
}
}
if (!zone) {
spinlock_unlock(&zones.lock);
interrupts_restore(ipl);
printf("Zone not found.\n");
return;
}
spinlock_lock(&zone->lock);
base = PFN2ADDR(zone->base);
count = zone->count;
busy_count = zone->busy_count;
free_count = zone->free_count;
spinlock_unlock(&zone->lock);
spinlock_unlock(&zones.lock);
interrupts_restore(ipl);
printf("Zone base address: %p\n", base);
printf("Zone size: %" PRIc " frames (%" PRIs " KiB)\n", count,
SIZE2KB(FRAMES2SIZE(count)));
printf("Allocated space: %" PRIc " frames (%" PRIs " KiB)\n",
busy_count, SIZE2KB(FRAMES2SIZE(busy_count)));
printf("Available space: %" PRIc " frames (%" PRIs " KiB)\n",
free_count, SIZE2KB(FRAMES2SIZE(free_count)));
}
/** @}
*/