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/*
* Copyright (c) 2001-2005 Jakub Jermar
* Copyright (c) 2005 Sergey Bondari
* Copyright (c) 2009 Martin Decky
* 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
*/
#include <arch/types.h>
#include <mm/frame.h>
#include <mm/as.h>
#include <panic.h>
#include <debug.h>
#include <adt/list.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>
zones_t zones;
/*
* Synchronization primitives used to sleep when there is no memory
* available.
*/
mutex_t mem_avail_mtx;
condvar_t mem_avail_cv;
size_t mem_avail_req = 0; /**< Number of frames requested. */
size_t mem_avail_gen = 0; /**< Generation counter. */
/********************/
/* Helper functions */
/********************/
static inline size_t frame_index(zone_t *zone, frame_t *frame)
{
return (size_t) (frame - zone->frames);
}
static inline size_t frame_index_abs(zone_t *zone, frame_t *frame)
{
return (size_t) (frame - zone->frames) + zone->base;
}
static inline bool frame_index_valid(zone_t *zone, size_t index)
{
return (index < zone->count);
}
static inline size_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;
}
/*******************/
/* Zones functions */
/*******************/
/** Insert-sort zone into zones list.
*
* Assume interrupts are disabled and zones lock is
* locked.
*
* @param base Base frame of the newly inserted zone.
* @param count Number of frames of the newly inserted zone.
*
* @return Zone number on success, -1 on error.
*
*/
static size_t zones_insert_zone(pfn_t base, size_t count)
{
if (zones.count + 1 == ZONES_MAX) {
printf("Maximum zone count %u exceeded!\n", ZONES_MAX);
return (size_t) -1;
}
size_t i;
for (i = 0; i < zones.count; i++) {
/* Check for overlap */
if (overlaps(base, count,
zones.info[i].base, zones.info[i].count)) {
printf("Zones overlap!\n");
return (size_t) -1;
}
if (base < zones.info[i].base)
break;
}
/* Move other zones up */
size_t j;
for (j = zones.count; j > i; j--) {
zones.info[j] = zones.info[j - 1];
zones.info[j].buddy_system->data =
(void *) &zones.info[j - 1];
}
zones.count++;
return i;
}
/** Get total available frames.
*
* Assume interrupts are disabled and zones lock is
* locked.
*
* @return Total number of available frames.
*
*/
#ifdef CONFIG_DEBUG
static size_t total_frames_free(void)
{
size_t total = 0;
size_t i;
for (i = 0; i < zones.count; i++)
total += zones.info[i].free_count;
return total;
}
#endif
/** Find a zone with a given frames.
*
* Assume interrupts are disabled and zones lock is
* locked.
*
* @param frame Frame number contained in zone.
* @param count Number of frames to look for.
* @param hint Used as zone hint.
*
* @return Zone index or -1 if not found.
*
*/
size_t find_zone(pfn_t frame, size_t count, size_t hint)
{
if (hint >= zones.count)
hint = 0;
size_t i = hint;
do {
if ((zones.info[i].base <= frame)
&& (zones.info[i].base + zones.info[i].count >= frame + count))
return i;
i++;
if (i >= zones.count)
i = 0;
} while (i != hint);
return (size_t) -1;
}
/** @return True if zone can allocate specified order */
static bool zone_can_alloc(zone_t *zone, uint8_t order)
{
return (zone_flags_available(zone->flags)
&& buddy_system_can_alloc(zone->buddy_system, order));
}
/** Find a zone that can allocate order frames.
*
* Assume interrupts are disabled and zones lock is
* locked.
*
* @param order Size (2^order) of free space we are trying to find.
* @param flags Required flags of the target zone.
* @param hind Preferred zone.
*
*/
static size_t find_free_zone(uint8_t order, zone_flags_t flags, size_t hint)
{
if (hint >= zones.count)
hint = 0;
size_t i = hint;
do {
/*
* Check whether the zone meets the search criteria.
*/
if ((zones.info[i].flags & flags) == flags) {
/*
* Check if the zone has 2^order frames area available.
*/
if (zone_can_alloc(&zones.info[i], order))
return i;
}
i++;
if (i >= zones.count)
i = 0;
} while (i != hint);
return (size_t) -1;
}
/**************************/
/* 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 *buddy, link_t *child,
uint8_t order)
{
frame_t *frame = list_get_instance(child, frame_t, buddy_link);
zone_t *zone = (zone_t *) buddy->data;
size_t 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 buddy 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 *buddy, link_t *block)
{
frame_t *frame = list_get_instance(block, frame_t, buddy_link);
zone_t *zone = (zone_t *) buddy->data;
ASSERT(IS_BUDDY_ORDER_OK(frame_index_abs(zone, frame),
frame->buddy_order));
bool is_left = IS_BUDDY_LEFT_BLOCK_ABS(zone, frame);
size_t index;
if (is_left) {
index = (frame_index(zone, frame)) +
(1 << frame->buddy_order);
} else { /* 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 buddy Buddy system.
* @param block Block to bisect.
*
* @return Right block.
*
*/
static link_t *zone_buddy_bisect(buddy_system_t *buddy, link_t *block)
{
frame_t *frame_l = list_get_instance(block, frame_t, buddy_link);
frame_t *frame_r = (frame_l + (1 << (frame_l->buddy_order - 1)));
return &frame_r->buddy_link;
}
/** Buddy system coalesce implementation.
*
* @param buddy 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 *buddy, link_t *block_1,
link_t *block_2)
{
frame_t *frame1 = list_get_instance(block_1, frame_t, buddy_link);
frame_t *frame2 = list_get_instance(block_2, frame_t, buddy_link);
return ((frame1 < frame2) ? block_1 : block_2);
}
/** Buddy system set_order implementation.
*
* @param buddy Buddy system.
* @param block Buddy system block.
* @param order Order to set.
*
*/
static void zone_buddy_set_order(buddy_system_t *buddy, link_t *block,
uint8_t order)
{
list_get_instance(block, frame_t, buddy_link)->buddy_order = order;
}
/** Buddy system get_order implementation.
*
* @param buddy Buddy system.
* @param block Buddy system block.
*
* @return Order of block.
*
*/
static uint8_t zone_buddy_get_order(buddy_system_t *buddy, link_t *block)
{
return list_get_instance(block, frame_t, buddy_link)->buddy_order;
}
/** Buddy system mark_busy implementation.
*
* @param buddy Buddy system.
* @param block Buddy system block.
*
*/
static void zone_buddy_mark_busy(buddy_system_t *buddy, link_t * block)
{
list_get_instance(block, frame_t, buddy_link)->refcount = 1;
}
/** Buddy system mark_available implementation.
*
* @param buddy Buddy system.
* @param block Buddy system block.
*/
static void zone_buddy_mark_available(buddy_system_t *buddy, link_t *block)
{
list_get_instance(block, frame_t, buddy_link)->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 and is available for allocation.
* 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)
{
ASSERT(zone_flags_available(zone->flags));
/* Allocate frames from zone buddy system */
link_t *link = buddy_system_alloc(zone->buddy_system, order);
ASSERT(link);
/* Update zone information. */
zone->free_count -= (1 << order);
zone->busy_count += (1 << order);
/* Frame will be actually a first frame of the block. */
frame_t *frame = list_get_instance(link, frame_t, buddy_link);
/* Get frame address */
return make_frame_index(zone, frame);
}
/** Free frame from zone.
*
* Assume zone is locked and is available for deallocation.
*
* @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, size_t frame_idx)
{
ASSERT(zone_flags_available(zone->flags));
frame_t *frame = &zone->frames[frame_idx];
/* Remember frame order */
uint8_t 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, size_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, size_t frame_idx)
{
ASSERT(zone_flags_available(zone->flags));
frame_t *frame = zone_get_frame(zone, frame_idx);
if (frame->refcount)
return;
link_t *link __attribute__ ((unused));
link = buddy_system_alloc_block(zone->buddy_system,
&frame->buddy_link);
ASSERT(link);
zone->free_count--;
}
/** Merge two zones.
*
* Expect buddy to point to space at least zone_conf_size large.
* Assume z1 & z2 are locked and compatible and zones lock is
* locked.
*
* @param z1 First zone to merge.
* @param z2 Second zone to merge.
* @param old_z1 Original date of the first zone.
* @param buddy Merged zone buddy.
*
*/
static void zone_merge_internal(size_t z1, size_t z2, zone_t *old_z1, buddy_system_t *buddy)
{
ASSERT(zone_flags_available(zones.info[z1].flags));
ASSERT(zone_flags_available(zones.info[z2].flags));
ASSERT(zones.info[z1].flags == zones.info[z2].flags);
ASSERT(zones.info[z1].base < zones.info[z2].base);
ASSERT(!overlaps(zones.info[z1].base, zones.info[z1].count,
zones.info[z2].base, zones.info[z2].count));
/* Difference between zone bases */
pfn_t base_diff = zones.info[z2].base - zones.info[z1].base;
zones.info[z1].count = base_diff + zones.info[z2].count;
zones.info[z1].free_count += zones.info[z2].free_count;
zones.info[z1].busy_count += zones.info[z2].busy_count;
zones.info[z1].buddy_system = buddy;
uint8_t order = fnzb(zones.info[z1].count);
buddy_system_create(zones.info[z1].buddy_system, order,
&zone_buddy_system_operations, (void *) &zones.info[z1]);
zones.info[z1].frames =
(frame_t *) ((uint8_t *) zones.info[z1].buddy_system
+ buddy_conf_size(order));
/* This marks all frames busy */
size_t i;
for (i = 0; i < zones.info[z1].count; i++)
frame_initialize(&zones.info[z1].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, clearing
* 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 < old_z1->count; i++)
zones.info[z1].frames[i] = old_z1->frames[i];
for (i = 0; i < zones.info[z2].count; i++)
zones.info[z1].frames[base_diff + i]
= zones.info[z2].frames[i];
i = 0;
while (i < zones.info[z1].count) {
if (zones.info[z1].frames[i].refcount) {
/* Skip busy frames */
i += 1 << zones.info[z1].frames[i].buddy_order;
} else {
/* Free frames, set refcount = 1
* (all free frames have refcount == 0, we need not
* to check the order)
*/
zones.info[z1].frames[i].refcount = 1;
zones.info[z1].frames[i].buddy_order = 0;
i++;
}
}
/* Add free blocks from the original zone z1 */
while (zone_can_alloc(old_z1, 0)) {
/* Allocate from the original zone */
pfn_t frame_idx = zone_frame_alloc(old_z1, 0);
/* Free the frame from the merged zone */
frame_t *frame = &zones.info[z1].frames[frame_idx];
frame->refcount = 0;
buddy_system_free(zones.info[z1].buddy_system, &frame->buddy_link);
}
/* Add free blocks from the original zone z2 */
while (zone_can_alloc(&zones.info[z2], 0)) {
/* Allocate from the original zone */
pfn_t frame_idx = zone_frame_alloc(&zones.info[z2], 0);
/* Free the frame from the merged zone */
frame_t *frame = &zones.info[z1].frames[base_diff + frame_idx];
frame->refcount = 0;
buddy_system_free(zones.info[z1].buddy_system, &frame->buddy_link);
}
}
/** Return old configuration frames into the zone.
*
* We have two cases:
* - The configuration data is outside the zone
* -> do nothing (perhaps call frame_free?)
* - The configuration data was created by zone_create
* or updated by reduce_region -> free every frame
*
* @param znum The actual zone where freeing should occur.
* @param pfn Old zone configuration frame.
* @param count Old zone frame count.
*
*/
static void return_config_frames(size_t znum, pfn_t pfn, size_t count)
{
ASSERT(zone_flags_available(zones.info[znum].flags));
size_t cframes = SIZE2FRAMES(zone_conf_size(count));
if ((pfn < zones.info[znum].base)
|| (pfn >= zones.info[znum].base + zones.info[znum].count))
return;
frame_t *frame __attribute__ ((unused));
frame = &zones.info[znum].frames[pfn - zones.info[znum].base];
ASSERT(!frame->buddy_order);
size_t i;
for (i = 0; i < cframes; i++) {
zones.info[znum].busy_count++;
zone_frame_free(&zones.info[znum],
pfn - zones.info[znum].base + i);
}
}
/** Reduce allocated block to count of order 0 frames.
*
* The allocated block needs 2^order frames. Reduce all frames
* in the 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 znum Zone.
* @param frame_idx Index the first frame of the block.
* @param count Allocated frames in block.
*
*/
static void zone_reduce_region(size_t znum, pfn_t frame_idx, size_t count)
{
ASSERT(zone_flags_available(zones.info[znum].flags));
ASSERT(frame_idx + count < zones.info[znum].count);
uint8_t order = zones.info[znum].frames[frame_idx].buddy_order;
ASSERT((size_t) (1 << order) >= count);
/* Reduce all blocks to order 0 */
size_t i;
for (i = 0; i < (size_t) (1 << order); i++) {
frame_t *frame = &zones.info[znum].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 < (size_t) (1 << order); i++)
zone_frame_free(&zones.info[znum], i + frame_idx);
}
/** Merge zones z1 and z2.
*
* The merged zones must be 2 zones with no zone existing in between
* (which means that z2 = z1 + 1). Both zones must be available zones
* with the same flags.
*
* 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 :-/
*
* The function uses
*
*/
bool zone_merge(size_t z1, size_t z2)
{
ipl_t ipl = interrupts_disable();
spinlock_lock(&zones.lock);
bool ret = true;
/* We can join only 2 zones with none existing inbetween,
* the zones have to be available and with the same
* set of flags
*/
if ((z1 >= zones.count) || (z2 >= zones.count)
|| (z2 - z1 != 1)
|| (!zone_flags_available(zones.info[z1].flags))
|| (!zone_flags_available(zones.info[z2].flags))
|| (zones.info[z1].flags != zones.info[z2].flags)) {
ret = false;
goto errout;
}
pfn_t cframes = SIZE2FRAMES(zone_conf_size(
zones.info[z2].base - zones.info[z1].base
+ zones.info[z2].count));
uint8_t order;
if (cframes == 1)
order = 0;
else
order = fnzb(cframes - 1) + 1;
/* Allocate merged zone data inside one of the zones */
pfn_t pfn;
if (zone_can_alloc(&zones.info[z1], order)) {
pfn = zones.info[z1].base + zone_frame_alloc(&zones.info[z1], order);
} else if (zone_can_alloc(&zones.info[z2], order)) {
pfn = zones.info[z2].base + zone_frame_alloc(&zones.info[z2], order);
} else {
ret = false;
goto errout;
}
/* Preserve original data from z1 */
zone_t old_z1 = zones.info[z1];
old_z1.buddy_system->data = (void *) &old_z1;
/* Do zone merging */
buddy_system_t *buddy = (buddy_system_t *) PA2KA(PFN2ADDR(pfn));
zone_merge_internal(z1, z2, &old_z1, buddy);
/* Free unneeded config frames */
zone_reduce_region(z1, pfn - zones.info[z1].base, cframes);
/* Subtract zone information from busy frames */
zones.info[z1].busy_count -= cframes;
/* Free old zone information */
return_config_frames(z1,
ADDR2PFN(KA2PA((uintptr_t) old_z1.frames)), old_z1.count);
return_config_frames(z1,
ADDR2PFN(KA2PA((uintptr_t) zones.info[z2].frames)),
zones.info[z2].count);
/* Move zones down */
size_t i;
for (i = z2 + 1; i < zones.count; i++) {
zones.info[i - 1] = zones.info[i];
zones.info[i - 1].buddy_system->data =
(void *) &zones.info[i - 1];
}
zones.count--;
errout:
spinlock_unlock(&zones.lock);
interrupts_restore(ipl);
return ret;
}
/** Merge all mergeable zones into one big zone.
*
* It is reasonable to do this on systems where
* BIOS reports parts in chunks, so that we could
* have 1 zone (it's faster).
*
*/
void zone_merge_all(void)
{
size_t i = 0;
while (i < zones.count) {
if (!zone_merge(i, i + 1))
i++;
}
}
/** Create new frame zone.
*
* @param zone Zone to construct.
* @param buddy Address of buddy system configuration information.
* @param start Physical address of the first frame within the zone.
* @param count Count of frames in zone.
* @param flags Zone flags.
*
* @return Initialized zone.
*
*/
static void zone_construct(zone_t *zone, buddy_system_t *buddy, pfn_t start, size_t count, zone_flags_t flags)
{
zone->base = start;
zone->count = count;
zone->flags = flags;
zone->free_count = count;
zone->busy_count = 0;
zone->buddy_system = buddy;
if (zone_flags_available(flags)) {
/*
* Compute order for buddy system and initialize
*/
uint8_t order = fnzb(count);
buddy_system_create(zone->buddy_system, order,
&zone_buddy_system_operations, (void *) zone);
/* Allocate frames _after_ the confframe */
/* Check sizes */
zone->frames = (frame_t *) ((uint8_t *) zone->buddy_system +
buddy_conf_size(order));
size_t i;
for (i = 0; i < count; i++)
frame_initialize(&zone->frames[i]);
/* Stuffing frames */
for (i = 0; i < count; i++) {
zone->frames[i].refcount = 0;
buddy_system_free(zone->buddy_system, &zone->frames[i].buddy_link);
}
} else
zone->frames = NULL;
}
/** 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(size_t count)
{
return (count * sizeof(frame_t) + buddy_conf_size(fnzb(count)));
}
/** 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.
*
*/
size_t zone_create(pfn_t start, size_t count, pfn_t confframe, zone_flags_t flags)
{
ipl_t ipl = interrupts_disable();
spinlock_lock(&zones.lock);
if (zone_flags_available(flags)) { /* Create available zone */
/* Theoretically we could have NULL here, practically make sure
* nobody tries to do that. If some platform requires, remove
* the assert
*/
ASSERT(confframe != NULL);
/* If confframe is supposed to be inside our zone, then make sure
* it does not span kernel & init
*/
size_t confcount = SIZE2FRAMES(zone_conf_size(count));
if ((confframe >= start) && (confframe < start + count)) {
for (; confframe < start + count; confframe++) {
uintptr_t 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;
size_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.");
}
size_t znum = zones_insert_zone(start, count);
if (znum == (size_t) -1) {
spinlock_unlock(&zones.lock);
interrupts_restore(ipl);
return (size_t) -1;
}
buddy_system_t *buddy = (buddy_system_t *) PA2KA(PFN2ADDR(confframe));
zone_construct(&zones.info[znum], buddy, start, count, flags);
/* If confdata in zone, mark as unavailable */
if ((confframe >= start) && (confframe < start + count)) {
size_t i;
for (i = confframe; i < confframe + confcount; i++)
zone_mark_unavailable(&zones.info[znum],
i - zones.info[znum].base);
}
spinlock_unlock(&zones.lock);
interrupts_restore(ipl);
return znum;
}
/* Non-available zone */
size_t znum = zones_insert_zone(start, count);
if (znum == (size_t) -1) {
spinlock_unlock(&zones.lock);
interrupts_restore(ipl);
return (size_t) -1;
}
zone_construct(&zones.info[znum], NULL, start, count, flags);
spinlock_unlock(&zones.lock);
interrupts_restore(ipl);
return znum;
}
/*******************/
/* Frame functions */
/*******************/
/** Set parent of frame. */
void frame_set_parent(pfn_t pfn, void *data, size_t hint)
{
ipl_t ipl = interrupts_disable();
spinlock_lock(&zones.lock);
size_t znum = find_zone(pfn, 1, hint);
ASSERT(znum != (size_t) -1);
zone_get_frame(&zones.info[znum],
pfn - zones.info[znum].base)->parent = data;
spinlock_unlock(&zones.lock);
interrupts_restore(ipl);
}
void *frame_get_parent(pfn_t pfn, size_t hint)
{
ipl_t ipl = interrupts_disable();
spinlock_lock(&zones.lock);
size_t znum = find_zone(pfn, 1, hint);
ASSERT(znum != (size_t) -1);
void *res = zone_get_frame(&zones.info[znum],
pfn - zones.info[znum].base)->parent;
spinlock_unlock(&zones.lock);
interrupts_restore(ipl);
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, frame_flags_t flags, size_t *pzone)
{
size_t size = ((size_t) 1) << order;
ipl_t ipl;
size_t hint = pzone ? (*pzone) : 0;
loop:
ipl = interrupts_disable();
spinlock_lock(&zones.lock);
/*
* First, find suitable frame zone.
*/
size_t znum = find_free_zone(order,
FRAME_TO_ZONE_FLAGS(flags), hint);
/* If no memory, reclaim some slab memory,
if it does not help, reclaim all */
if ((znum == (size_t) -1) && (!(flags & FRAME_NO_RECLAIM))) {
spinlock_unlock(&zones.lock);
interrupts_restore(ipl);
size_t freed = slab_reclaim(0);
ipl = interrupts_disable();
spinlock_lock(&zones.lock);
if (freed > 0)
znum = find_free_zone(order,
FRAME_TO_ZONE_FLAGS(flags), hint);
if (znum == (size_t) -1) {
spinlock_unlock(&zones.lock);
interrupts_restore(ipl);
freed = slab_reclaim(SLAB_RECLAIM_ALL);
ipl = interrupts_disable();
spinlock_lock(&zones.lock);
if (freed > 0)
znum = find_free_zone(order,
FRAME_TO_ZONE_FLAGS(flags), hint);
}
}
if (znum == (size_t) -1) {
if (flags & FRAME_ATOMIC) {
spinlock_unlock(&zones.lock);
interrupts_restore(ipl);
return NULL;
}
#ifdef CONFIG_DEBUG
size_t avail = total_frames_free();
#endif
spinlock_unlock(&zones.lock);
interrupts_restore(ipl);
/*
* Sleep until some frames are available again.
*/
#ifdef CONFIG_DEBUG
printf("Thread %" PRIu64 " waiting for %" PRIs " frames, "
"%" PRIs " available.\n", THREAD->tid, size, avail);
#endif
mutex_lock(&mem_avail_mtx);
if (mem_avail_req > 0)
mem_avail_req = min(mem_avail_req, size);
else
mem_avail_req = size;
size_t gen = mem_avail_gen;
while (gen == mem_avail_gen)
condvar_wait(&mem_avail_cv, &mem_avail_mtx);
mutex_unlock(&mem_avail_mtx);
#ifdef CONFIG_DEBUG
printf("Thread %" PRIu64 " woken up.\n", THREAD->tid);
#endif
goto loop;
}
pfn_t pfn = zone_frame_alloc(&zones.info[znum], order)
+ zones.info[znum].base;
spinlock_unlock(&zones.lock);
interrupts_restore(ipl);
if (pzone)
*pzone = znum;
if (flags & FRAME_KA)
return (void *) PA2KA(PFN2ADDR(pfn));
return (void *) PFN2ADDR(pfn);
}
/** 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 = interrupts_disable();
spinlock_lock(&zones.lock);
/*
* First, find host frame zone for addr.
*/
pfn_t pfn = ADDR2PFN(frame);
size_t znum = find_zone(pfn, 1, NULL);
ASSERT(znum != (size_t) -1);
zone_frame_free(&zones.info[znum], pfn - zones.info[znum].base);
spinlock_unlock(&zones.lock);
interrupts_restore(ipl);
/*
* Signal that some memory has been freed.
*/
mutex_lock(&mem_avail_mtx);
if (mem_avail_req > 0)
mem_avail_req--;
if (mem_avail_req == 0) {
mem_avail_gen++;
condvar_broadcast(&mem_avail_cv);
}
mutex_unlock(&mem_avail_mtx);
}
/** 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 = interrupts_disable();
spinlock_lock(&zones.lock);
/*
* First, find host frame zone for addr.
*/
size_t znum = find_zone(pfn, 1, NULL);
ASSERT(znum != (size_t) -1);
zones.info[znum].frames[pfn - zones.info[znum].base].refcount++;
spinlock_unlock(&zones.lock);
interrupts_restore(ipl);
}
/** Mark given range unavailable in frame zones. */
void frame_mark_unavailable(pfn_t start, size_t count)
{
ipl_t ipl = interrupts_disable();
spinlock_lock(&zones.lock);
size_t i;
for (i = 0; i < count; i++) {
size_t znum = find_zone(start + i, 1, 0);
if (znum == (size_t) -1) /* PFN not found */
continue;
zone_mark_unavailable(&zones.info[znum],
start + i - zones.info[znum].base);
}
spinlock_unlock(&zones.lock);
interrupts_restore(ipl);
}
/** 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));
size_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)
{
ipl_t ipl = interrupts_disable();
spinlock_lock(&zones.lock);
uint64_t total = 0;
size_t i;
for (i = 0; i < zones.count; i++)
total += (uint64_t) FRAMES2SIZE(zones.info[i].count);
spinlock_unlock(&zones.lock);
interrupts_restore(ipl);
return total;
}
/** Prints list of zones. */
void zone_print_list(void)
{
#ifdef __32_BITS__
printf("# base address frames flags free frames busy frames\n");
printf("-- ------------ ------------ -------- ------------ ------------\n");
#endif
#ifdef __64_BITS__
printf("# base address frames flags 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).
*/
size_t i;
for (i = 0;; i++) {
ipl_t ipl = interrupts_disable();
spinlock_lock(&zones.lock);
if (i >= zones.count) {
spinlock_unlock(&zones.lock);
interrupts_restore(ipl);
break;
}
uintptr_t base = PFN2ADDR(zones.info[i].base);
size_t count = zones.info[i].count;
zone_flags_t flags = zones.info[i].flags;
size_t free_count = zones.info[i].free_count;
size_t busy_count = zones.info[i].busy_count;
spinlock_unlock(&zones.lock);
interrupts_restore(ipl);
bool available = zone_flags_available(flags);
printf("%-2" PRIs, i);
#ifdef __32_BITS__
printf(" %10p", base);
#endif
#ifdef __64_BITS__
printf(" %18p", base);
#endif
printf(" %12" PRIs " %c%c%c ", count,
available ? 'A' : ' ',
(flags & ZONE_RESERVED) ? 'R' : ' ',
(flags & ZONE_FIRMWARE) ? 'F' : ' ');
if (available)
printf("%12" PRIs " %12" PRIs,
free_count, busy_count);
printf("\n");
}
}
/** Prints zone details.
*
* @param num Zone base address or zone number.
*
*/
void zone_print_one(size_t num)
{
ipl_t ipl = interrupts_disable();
spinlock_lock(&zones.lock);
size_t znum = (size_t) -1;
size_t i;
for (i = 0; i < zones.count; i++) {
if ((i == num) || (PFN2ADDR(zones.info[i].base) == num)) {
znum = i;
break;
}
}
if (znum == (size_t) -1) {
spinlock_unlock(&zones.lock);
interrupts_restore(ipl);
printf("Zone not found.\n");
return;
}
uintptr_t base = PFN2ADDR(zones.info[i].base);
zone_flags_t flags = zones.info[i].flags;
size_t count = zones.info[i].count;
size_t free_count = zones.info[i].free_count;
size_t busy_count = zones.info[i].busy_count;
spinlock_unlock(&zones.lock);
interrupts_restore(ipl);
bool available = zone_flags_available(flags);
printf("Zone number: %" PRIs "\n", znum);
printf("Zone base address: %p\n", base);
printf("Zone size: %" PRIs " frames (%" PRIs " KiB)\n", count,
SIZE2KB(FRAMES2SIZE(count)));
printf("Zone flags: %c%c%c\n",
available ? 'A' : ' ',
(flags & ZONE_RESERVED) ? 'R' : ' ',
(flags & ZONE_FIRMWARE) ? 'F' : ' ');
if (available) {
printf("Allocated space: %" PRIs " frames (%" PRIs " KiB)\n",
busy_count, SIZE2KB(FRAMES2SIZE(busy_count)));
printf("Available space: %" PRIs " frames (%" PRIs " KiB)\n",
free_count, SIZE2KB(FRAMES2SIZE(free_count)));
}
}
/** @}
*/