wip: frame_allocator working pretty good (?)

core: remove physical allocatory
This commit is contained in:
0x35c 2024-11-19 16:57:19 +01:00
parent e8fd6c55eb
commit 3315d85e0c
14 changed files with 61 additions and 471 deletions

View File

@ -21,9 +21,25 @@
#define GET_PAGE_ADDR(pd_index, pt_index) \ #define GET_PAGE_ADDR(pd_index, pt_index) \
((((uint32_t)pd_index * 1024) + (uint32_t)pt_index) * 4096) ((((uint32_t)pd_index * 1024) + (uint32_t)pt_index) * 4096)
#define GET_FRAME(frame_table, i) (frame_table[i / 8] & (1 << (i % 8)))
#define SET_FRAME(frame_table, i, used) \
do { \
if (used) \
frame_table[i / 8] |= (1 << (i % 8)); \
else \
frame_table[i / 8] &= ~(1 << (i % 8)); \
} while (0)
/*
* len is the total size of the zone (ratio starnakin)
* size is the remaining usable size after allocating
* the struct for the linked list
*/
struct frame_zone { struct frame_zone {
void *addr; void *addr;
uint32_t first_free_frame;
uint32_t *frame_table; uint32_t *frame_table;
uint32_t len;
uint32_t size; uint32_t size;
uint32_t remaining_frames; uint32_t remaining_frames;
struct frame_zone *next; struct frame_zone *next;
@ -40,8 +56,8 @@ extern struct frame_zone *head;
uint32_t *virt_to_phys(uint32_t *virt_addr); uint32_t *virt_to_phys(uint32_t *virt_addr);
void init_memory(multiboot_info_t *mbd, uint32_t magic); void init_memory(multiboot_info_t *mbd, uint32_t magic);
void *alloc_frames(size_t size); void *alloc_frame(void);
int free_frames(void *frame_ptr, size_t size); int free_frame(void *frame_ptr);
void *alloc_pages(size_t size); void *alloc_pages(size_t size);
int free_pages(void *page_ptr, size_t size); int free_pages(void *page_ptr, size_t size);
void init_page_table(uint32_t page_table[1024], uint16_t start); void init_page_table(uint32_t page_table[1024], uint16_t start);

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@ -66,9 +66,9 @@ void kernel_main(multiboot_info_t *mbd, uint32_t magic)
"I see no way to confuse an array of 256 seg:off pairs with a " "I see no way to confuse an array of 256 seg:off pairs with a "
"complex 8*unknown quantity -byte descriptor table. -- Troy " "complex 8*unknown quantity -byte descriptor table. -- Troy "
"Martin 03:50, 22 March 2009 (UTC)\n"); "Martin 03:50, 22 March 2009 (UTC)\n");
alloc_frames(1); /* alloc_frame(); */
/* vmalloc(10); */ /* vmalloc(10); */
/* while (vmalloc(10)) */ while (vmalloc(10))
/* ; */ ;
shell_init(); shell_init();
} }

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@ -8,28 +8,36 @@
#include "string.h" #include "string.h"
#include "utils.h" #include "utils.h"
void *alloc_frames(size_t size) void *alloc_frame(void)
{ {
const uint32_t nb_frames = CEIL(size, PAGE_SIZE); struct frame_zone *it = head;
for (uint32_t i = 0; i < mmap_length; i++) { while (it && !it->remaining_frames)
multiboot_memory_map_t *mmmt = it = it->next;
(multiboot_memory_map_t *)mmap_addr + i; if (it->remaining_frames == 0) {
if (mmmt->type == MULTIBOOT_MEMORY_AVAILABLE) { kprintf(KERN_CRIT "No memory zone available (ratio)\n");
kprintf("type: %d, addr: %p, len: %u, size: %u, \n",
mmmt->type, mmmt->addr, mmmt->len, mmmt->size);
}
PRINT_PTR(mmmt);
}
PRINT_PTR(head);
PRINT_PTR(head->addr);
PRINT_PTR(head->frame_table);
PRINT_UINT(head->size);
PRINT_UINT(head->remaining_frames);
PRINT_PTR(head->next);
return NULL; return NULL;
}
size_t i = it->first_free_frame;
for (; GET_FRAME(it->frame_table, i); i++)
;
it->first_free_frame++;
it->remaining_frames--;
SET_FRAME(it->frame_table, i, 1);
return it->addr + i * PAGE_SIZE;
} }
int free_frames(void *frame_ptr, size_t size) int free_frame(void *frame_ptr)
{ {
struct frame_zone *it = head;
while (it && (frame_ptr < it->addr || frame_ptr >= it->addr + it->len))
it = it->next;
uint32_t index =
(frame_ptr + (it->len - it->size) - it->addr) / PAGE_SIZE;
SET_FRAME(it->frame_table, index, 0);
if (it->first_free_frame > index)
it->first_free_frame = index;
it->remaining_frames++;
return 0; return 0;
} }

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@ -53,10 +53,11 @@ static void add_frame_node(multiboot_memory_map_t *mmmt)
init_page_table(frame_zones_page_table, 0); init_page_table(frame_zones_page_table, 0);
page_directory[1022] = page_directory[1022] =
((uint32_t)frame_zones_page_table - HEAP_END) | 0x03; ((uint32_t)frame_zones_page_table - HEAP_END) | 0x03;
frame_zones_page_table[index++] = frame_zones_page_table[index] =
((uint32_t)zone & PAGE_MASK) | INIT_FLAGS; ((uint32_t)zone & PAGE_MASK) | INIT_FLAGS;
struct frame_zone *current = struct frame_zone *current =
(struct frame_zone *)GET_PAGE_ADDR(1022, 0); (struct frame_zone *)GET_PAGE_ADDR(1022, index++);
memset(current, 0, sizeof(struct frame_zone)); memset(current, 0, sizeof(struct frame_zone));
current->addr = (void *)mmmt->addr; current->addr = (void *)mmmt->addr;
current->frame_table = (uint32_t *)current + sizeof(struct frame_zone); current->frame_table = (uint32_t *)current + sizeof(struct frame_zone);
@ -68,16 +69,18 @@ static void add_frame_node(multiboot_memory_map_t *mmmt)
frame_zones_page_table[index] = frame_zones_page_table[index] =
((uint32_t)zone + PAGE_SIZE & PAGE_MASK) | INIT_FLAGS; ((uint32_t)zone + PAGE_SIZE & PAGE_MASK) | INIT_FLAGS;
// glhf reading this bozo // glhf reading this bozo
current->len = mmmt->len;
current->size = (mmmt->len - (sizeof(struct frame_zone) + current->size = (mmmt->len - (sizeof(struct frame_zone) +
(mmmt->len / PAGE_SIZE) / 32)); (mmmt->len / PAGE_SIZE) / 32));
current->remaining_frames = current->size / PAGE_SIZE; current->remaining_frames = current->size / PAGE_SIZE;
current->first_free_frame = 0;
current->next = NULL; current->next = NULL;
struct frame_zone *it = head; if (!head) {
if (!it) {
head = current; head = current;
return; return;
} }
struct frame_zone *it = head;
while (it->next) while (it->next)
it = it->next; it = it->next;
it->next = current; it->next = current;

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@ -46,11 +46,10 @@ void *alloc_pages(size_t size)
return NULL; return NULL;
} }
for (size_t i = index; i - (size_t)index < nb_pages; i++) { for (size_t i = index; i - (size_t)index < nb_pages; i++) {
void *frame = alloc_frames(PAGE_SIZE); void *frame = alloc_frame();
if (!frame) { if (!frame) {
for (size_t j = index; j < i; j++) for (size_t j = index; j < i; j++)
free_frames((void *)(page_table[j] >> 12), free_frame((void *)(page_table[j] >> 12));
PAGE_SIZE);
return NULL; return NULL;
} }
page_table[i] = ((uint32_t)frame & PAGE_MASK) | INIT_FLAGS; page_table[i] = ((uint32_t)frame & PAGE_MASK) | INIT_FLAGS;
@ -83,7 +82,7 @@ int free_pages(void *page_ptr, size_t size)
kprintf(KERN_WARNING "Page already free\n"); kprintf(KERN_WARNING "Page already free\n");
return -2; return -2;
} }
free_frames((void *)(page_table[i] & PAGE_MASK), PAGE_SIZE); free_frame((void *)(page_table[i] & PAGE_MASK));
page_table[i] = i << 12; page_table[i] = i << 12;
} }

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@ -9,7 +9,7 @@ void init_page_table(uint32_t page_table[1024], uint16_t start)
int16_t add_page_table(uint16_t pd_index) int16_t add_page_table(uint16_t pd_index)
{ {
void *frame = alloc_frames(PAGE_SIZE); void *frame = alloc_frame();
if (!frame) if (!frame)
return -1; return -1;
page_table_default[PT_START + pd_index] = page_table_default[PT_START + pd_index] =

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@ -1,65 +0,0 @@
#include "alloc.h"
#include "kprintf.h"
#include "memory.h"
#include <stdint.h>
Zone *kzones[3];
static void add_zone(Zone *zone, block_type_t type)
{
// We put the zone at the beginning of the list
if (kzones[type]) {
zone->next = kzones[type];
kzones[type]->prev = zone;
}
kzones[type] = zone;
}
static void new_block(Zone *zone, uint32_t zone_size)
{
Block *new_block = (Block *)align_mem((uint32_t)zone + sizeof(Zone));
// Metadata
new_block->in_use = false;
new_block->size = zone_size - sizeof(Zone) - sizeof(Block);
new_block->sub_size = new_block->size;
new_block->ptr = (Block *)((uint32_t)new_block + sizeof(Block));
new_block->zone = zone;
// Init future linked lists
new_block->prev = NULL;
new_block->prev_free = NULL;
new_block->prev_used = NULL;
new_block->next = NULL;
new_block->next_free = NULL;
new_block->next_used = NULL;
if (zone->free) {
zone->free->prev = new_block;
zone->free->prev_free = new_block;
new_block->next = zone->free;
new_block->next_free = zone->free;
}
zone->free = new_block;
}
int new_kzone(block_type_t type, uint32_t size)
{
void *heap = alloc_frames(size);
if (heap == NULL) {
kprintf(KERN_ERR "error: alloc_frames failed\n");
return (-1);
}
Zone *zone = (Zone *)heap;
zone->type = type;
zone->size = size;
zone->used = NULL;
zone->next = NULL;
zone->prev = NULL;
new_block(zone, size);
add_zone(heap, type);
return (0);
}

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@ -1,50 +0,0 @@
#include "alloc.h"
#include "kprintf.h"
#include <stdint.h>
// FULL_INFO is to display (or not) both used and unused blocks
#define FULL_INFO 1
void show_kalloc_mem(void)
{
char *const kzones_name[3] = {"TINY", "SMALL", "LARGE"};
uint32_t total_size = 0;
for (block_type_t type = 0; type < 3; ++type) {
int count = 0;
for (Zone *zone_it = kzones[type]; zone_it != NULL;
zone_it = zone_it->next) {
#if FULL_INFO
if (zone_it->free)
kprintf("---------- AVAILABLE %s [n°%d - %p] "
"----------\n",
kzones_name[type], count, zone_it);
for (Block *block_it = zone_it->free; block_it != NULL;
block_it = block_it->next_free) {
kprintf("%p - %p : %u bytes\n", block_it->ptr,
(uint32_t)block_it->ptr +
block_it->sub_size + sizeof(Block),
block_it->sub_size);
}
if (zone_it->free)
kprintf("\n");
#endif
if (zone_it->used)
kprintf("---------- IN_USE %s [n°%d - %p] "
"----------\n",
kzones_name[type], count, zone_it);
for (Block *block_it = zone_it->used; block_it != NULL;
block_it = block_it->next_used) {
kprintf("%p - %p : %u bytes\n", block_it->ptr,
(uint32_t)block_it->ptr +
block_it->sub_size + sizeof(Block),
block_it->sub_size);
total_size += block_it->sub_size;
}
if (zone_it->used)
kprintf("\n");
count++;
}
}
kprintf("Total: %u\n", total_size);
}

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@ -1,116 +0,0 @@
#include "alloc.h"
#include "kprintf.h"
#include "memory.h"
#include <stdint.h>
static void remove_used(Block *to_free)
{
Block *left = to_free->prev_used;
Block *right = to_free->next_used;
to_free->next_used = NULL;
to_free->prev_used = NULL;
if (!left && !right) {
to_free->zone->used = NULL;
return;
}
if (!left)
to_free->zone->used = right;
else
left->next_used = right;
if (right)
right->prev_used = left;
}
/*
* If all the blocks of the zone have been kfreed,
* we can unmap the zone and delete it from the list of kzones
*/
static int unmap_zone(Zone *zone)
{
int err = 0;
block_type_t type = zone->type;
Zone *left = zone->prev;
Zone *right = zone->next;
zone->prev = NULL;
zone->next = NULL;
if (!left && !right) {
kzones[type] = NULL;
goto unmap;
}
if (!left)
kzones[type] = right;
else
left->next = right;
if (right)
right->prev = left;
unmap:
err = free_frames((void *)zone, zone->size);
if (err)
kprintf(KERN_ERR "error: munmap failed\n");
return (err);
}
/*
* If the newly kfreed block is next to another previously
* kfreed block, merge both of these and update the size
*/
static Block *merge_blocks(Block *left, Block *right)
{
if (right->next)
right->next->prev = left;
if (right->next_free) {
right->next_free->prev_free = left;
left->next_free = right->next_free;
}
left->next = right->next;
left->size += right->size + sizeof(Block);
return (left);
}
// Simply add the new block to the list of available blocks
static int add_available(Block *available, Block *merged)
{
Zone *zone = available->zone;
if (merged != zone->free && available != zone->free)
available->next_free = zone->free;
if (zone->free)
zone->free->prev_free = available;
zone->free = available;
if (zone->type == LARGE)
return (unmap_zone(zone));
return (0);
}
/*
* ptr: pointer to kfree, if the pointer is invalid the kfree()
* function will have an undefined behavior (most likely segfault)
*
* First, we remove the block from the list of in_use blocks
* Then, we check if the block needs to be merged with another
* neighboring block, if so we replace the previous block by the
* newly merged block
* Finally, we add the block to the list of available blocks
*/
void kfree(void *ptr)
{
if (ptr == NULL)
return;
Block *to_free = (Block *)((uint32_t)ptr - sizeof(Block));
Block *to_merge = NULL;
to_free->in_use = false;
remove_used(to_free);
if (to_free->prev && !to_free->prev->in_use) {
to_merge = to_free;
to_free = merge_blocks(to_free->prev, to_free);
}
if (to_free->next && !to_free->next->in_use) {
to_merge = to_free->next;
to_free = merge_blocks(to_free, to_free->next);
}
int err = add_available(to_free, to_merge);
if (err)
kprintf(KERN_ERR "kfree: fatal error\n");
}

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@ -1,152 +0,0 @@
#include "alloc.h"
#include "debug.h"
#include "kprintf.h"
#include <stdint.h>
/*
* Find first available (not in_use) block
* in a zone matching the size we need
*/
static Block *find_block(Zone *head, uint32_t size)
{
for (Zone *zone_it = head; zone_it != NULL; zone_it = zone_it->next) {
for (Block *block_it = zone_it->free; block_it != NULL;
block_it = block_it->next_free) {
assert(!block_it->in_use);
if (size <= block_it->size) {
assert(block_it->zone == zone_it);
return (block_it);
}
}
}
return (NULL);
}
// PARTIALLY DEPRECATED
/*
* This will split the newly allocated block to use
* the remaining bytes for a new block
* This is our linked list of blocks
* ... -> [5] -> [6] -> ...
* After the allocation, this will become
* ... -> [5] -> [new] -> [6] -> ...
*
* For an example of [5].size = 32 and requiring a kmalloc of 10
* Let's say the metadata takes a size of 2:
* ... -> [metadata][data][remaining size] -> [6]
* ^ ^ ^
* 2 10 20
*
* So now our block [new] will become:
* [5] -> [metadata][available data] -> [6]
* ^ ^
* 2 18
* We can see that it now has its own metadata and available
* data and it points towards [6]
*/
static void frag_block(Zone *zone, Block *old_block, uint32_t size)
{
Block *new_block = (Block *)align_mem((uint32_t)old_block + size);
assert(!(new_block >=
(Block *)((uint32_t)zone + get_zone_size(zone->type))));
// Newly created block metadata
new_block->size = old_block->size - size;
new_block->sub_size = new_block->size;
new_block->in_use = false;
new_block->ptr = (void *)((uint32_t)new_block + sizeof(Block));
new_block->zone = zone;
new_block->prev = old_block;
new_block->next = old_block->next;
old_block->next = new_block;
new_block->prev_used = NULL;
new_block->next_used = NULL;
new_block->prev_free = old_block->prev_free;
new_block->next_free = old_block->next_free;
if (zone->free == old_block)
zone->free = new_block;
old_block->next_free = NULL;
old_block->prev_free = NULL;
// Newly in_use block metadata
old_block->in_use = true;
old_block->size = size - sizeof(Block);
old_block->sub_size = old_block->size;
if (zone->used == NULL) {
zone->used = old_block;
return;
}
old_block->prev_used = NULL;
old_block->next_used = zone->used;
zone->used->prev_used = old_block;
zone->used = old_block;
}
// Set the block to use and unset free
static void save_block(Zone *head, Block *block, Zone *zone)
{
zone->free = NULL;
block->in_use = true;
if (head->used) {
head->used->prev_used = block;
head->used->prev = block;
block->next = head->used;
block->next_used = head->used;
}
head->used = block;
}
/*
* size: size needed by the user to get allocated
*
* First, we init the allocator if it's the first time
* Then we search if there is an available block in all
* the kzones currently mapped
* If no block has been found (NULL), we create 1 new zone of
* the corresponding type
* We then search again for an available block (should not be NULL)
* Finally, if type == LARGE, we just have to change the block to used
* else, we frag the block to use just what's needed
*
* ptr: returns the aligned pointer of the block (after the metadata)
*/
void *kmalloc(uint32_t size)
{
void *ptr = NULL;
if (size == 0) {
kprintf(KERN_WARNING "kmalloc: can't kmalloc(0)\n");
return NULL;
}
// Find the zone we need to search
block_type_t type = get_type(size);
Zone *head = kzones[type];
// Find an available block in a zone of type "type"
Block *available = find_block(head, size);
if (available == NULL) {
uint32_t full_size;
if (type == LARGE)
full_size = size + sizeof(Block) + sizeof(Zone);
else
full_size = get_zone_size(type);
if (new_kzone(type, full_size) == -1)
return NULL;
head = kzones[type];
available = find_block(head, size);
}
assert(available != NULL);
if (type == LARGE)
save_block(head, available, available->zone);
else
frag_block(available->zone, available, size + sizeof(Block));
ptr = available->ptr;
return ptr;
}

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@ -1,37 +0,0 @@
#include "alloc.h"
#include "string.h"
#include <stdint.h>
// Prototype for kfree and kmalloc
void kfree(void *ptr);
void *kmalloc(uint32_t size);
/*
* ptr: block to resize (undefined behavior if invalid)
* size: size needed by the user to get kreallocated
*
* If we have a size <= to the previous size, we don't have
* to do anything, we just change sub_size for info purposes
* and return the same pointer
* Else, we allocate a new block and copy the content of
* the previous block in the new one and kfree the old block
*
* ptr: returns the aligned pointer of the kreallocated block
*/
void *krealloc(void *ptr, uint32_t size)
{
void *new_ptr = NULL;
if (ptr == NULL)
return NULL;
Block *block = (Block *)((uint32_t)ptr - sizeof(Block));
if (block->size >= size) {
block->sub_size = size;
return (ptr);
}
new_ptr = kmalloc(size);
if (new_ptr == NULL)
return NULL;
memmove(new_ptr, ptr, block->size);
kfree(ptr);
return (new_ptr);
}

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@ -1,9 +0,0 @@
#include "alloc.h"
#include <stdint.h>
uint32_t ksize(void *ptr)
{
Block *meta_data = (Block *)((uint32_t)ptr - sizeof(Block));
return meta_data->sub_size;
}

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@ -32,6 +32,6 @@ void *vrealloc(void *ptr, uint32_t size)
if (new_ptr == NULL) if (new_ptr == NULL)
return NULL; return NULL;
memmove(new_ptr, ptr, block->size); memmove(new_ptr, ptr, block->size);
kfree(ptr); vfree(ptr);
return (new_ptr); return (new_ptr);
} }

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@ -4,13 +4,6 @@
void heap_cmd(char *arg) void heap_cmd(char *arg)
{ {
if (!arg) (void)arg;
kprintf(KERN_INFO "You must specify an argument (phys/virt)\n");
else if (!strcmp(arg, "phys"))
show_kalloc_mem();
else if (!strcmp(arg, "virt"))
show_valloc_mem(); show_valloc_mem();
else
kprintf(KERN_INFO "%s: invalid argument to heap (phys/virt)\n",
arg);
} }