From 9f142941c380b5a7a5aa7a92f65b8f9020e67a96 Mon Sep 17 00:00:00 2001
From: 0x35c <>
Date: Wed, 12 Nov 2025 16:02:52 +0100
Subject: [PATCH] wip: separate allocators into a kernel one and a user one

---
 headers/memory.h                      |  6 +-
 src/interrupt/handler.c               |  2 -
 src/kpanic.c                          |  8 +--
 src/memory/{phys => kern}/allocator.c |  6 +-
 src/memory/{phys => kern}/info.c      |  0
 src/memory/{phys => kern}/kfree.c     |  2 +-
 src/memory/{phys => kern}/kmalloc.c   |  0
 src/memory/{phys => kern}/krealloc.c  |  0
 src/memory/{phys => kern}/ksize.c     |  0
 src/memory/kern/page.c                | 92 +++++++++++++++++++++++++++
 src/memory/load_pd.s                  | 19 +++---
 src/memory/memory.c                   |  2 +-
 src/memory/page_directory.c           |  2 +-
 src/memory/page_table.c               |  3 +-
 src/memory/paging.s                   | 21 +++---
 src/memory/virt/allocator.c           |  5 +-
 src/memory/{ => virt}/page.c          |  5 +-
 src/memory/virt/vfree.c               |  2 +-
 src/multiboot.c                       |  4 +-
 src/multitasking/fork.c               |  2 +-
 src/multitasking/process.c            | 10 +--
 src/multitasking/thread.c             | 14 ++--
 22 files changed, 149 insertions(+), 56 deletions(-)
 rename src/memory/{phys => kern}/allocator.c (94%)
 rename src/memory/{phys => kern}/info.c (100%)
 rename src/memory/{phys => kern}/kfree.c (98%)
 rename src/memory/{phys => kern}/kmalloc.c (100%)
 rename src/memory/{phys => kern}/krealloc.c (100%)
 rename src/memory/{phys => kern}/ksize.c (100%)
 create mode 100644 src/memory/kern/page.c
 rename src/memory/{ => virt}/page.c (93%)

diff --git a/headers/memory.h b/headers/memory.h
index a46420a..6316a2e 100644
--- a/headers/memory.h
+++ b/headers/memory.h
@@ -59,8 +59,10 @@ void init_memory(multiboot_info_t *mbd, uint32_t magic);
 void *alloc_frame(void);
 int free_frame(void *frame_ptr);
 int8_t add_single_page(void *frame);
-void *alloc_pages(size_t size, void **phys_addr);
-int free_pages(void *page_ptr, size_t size);
+void *kalloc_pages(size_t size, void **phys_addr);
+void *valloc_pages(size_t size, void **phys_addr);
+int kfree_pages(void *page_ptr, size_t size);
+int vfree_pages(void *page_ptr, size_t size);
 void init_page_table(uint32_t page_table[1024], uint16_t start);
 int16_t add_page_table(uint16_t pd_index);
 void switch_pd(uint32_t *pd, uint32_t *cr3);
diff --git a/src/interrupt/handler.c b/src/interrupt/handler.c
index 1ab1436..8b77f9c 100644
--- a/src/interrupt/handler.c
+++ b/src/interrupt/handler.c
@@ -36,8 +36,6 @@ void isr_handler(struct registers *regs)
 {
 	uint8_t i = 0;
 	while (i < ARRAY_SIZE(faults)) {
-		if (i == 6)
-			reboot();
 		if (i == regs->int_no)
 			kpanic("interrupt: %s\n", faults[i]);
 		i++;
diff --git a/src/kpanic.c b/src/kpanic.c
index 9ff1f7a..31637c2 100644
--- a/src/kpanic.c
+++ b/src/kpanic.c
@@ -23,10 +23,10 @@ __attribute__((noreturn)) void kpanic(const char *format, ...)
 	va_end(va);
 
 	uint32_t faulting_address;
-	// __asm__ __volatile__("mov %%cr2, %0" : "=r"(faulting_address));
-	// kprintf("fault at address: %p\n", faulting_address);
-	/* for (int i = 16; i < 32; i++) */
-	/* 	kprintf("%p\n", page_table1[i]); */
+	__asm__ __volatile__("mov %%cr2, %0" : "=r"(faulting_address));
+	kprintf("fault at address: %p\n", faulting_address);
+	// for (int i = 16; i < 32; i++)
+	// 	kprintf("%p\n", page_table1[i]);
 	// show_valloc_mem();
 	/* kprintf("\n\n"); */
 	/* print_stack(); */
diff --git a/src/memory/phys/allocator.c b/src/memory/kern/allocator.c
similarity index 94%
rename from src/memory/phys/allocator.c
rename to src/memory/kern/allocator.c
index 560ff75..cfb905e 100644
--- a/src/memory/phys/allocator.c
+++ b/src/memory/kern/allocator.c
@@ -1,9 +1,8 @@
 #include "alloc.h"
 #include "assert.h"
-#include "kpanic.h"
 #include "kprintf.h"
 #include "memory.h"
-#include "process.h"
+#include "string.h"
 
 Zone *kzones[3];
 
@@ -50,11 +49,12 @@ static void new_block(Zone *zone, uint32_t zone_size)
 int new_kzone(block_type_t type, uint32_t size)
 {
 	// assert(current_task->pid);
-	void *heap = alloc_frame();
+	void *heap = kalloc_pages(size, NULL);
 	if (heap == NULL) {
 		kprintf(KERN_ERR "error: alloc_frame failed\n");
 		return (-1);
 	}
+	memset(heap, 0, size);
 
 	Zone *zone = (Zone *)heap;
 	zone->type = type;
diff --git a/src/memory/phys/info.c b/src/memory/kern/info.c
similarity index 100%
rename from src/memory/phys/info.c
rename to src/memory/kern/info.c
diff --git a/src/memory/phys/kfree.c b/src/memory/kern/kfree.c
similarity index 98%
rename from src/memory/phys/kfree.c
rename to src/memory/kern/kfree.c
index 6002bc3..7d52c8f 100644
--- a/src/memory/phys/kfree.c
+++ b/src/memory/kern/kfree.c
@@ -47,7 +47,7 @@ static int unmap_zone(Zone *zone)
 	if (right)
 		right->prev = left;
 unmap:
-	err = free_pages((void *)zone, zone->size);
+	err = kfree_pages((void *)zone, zone->size);
 	if (err)
 		kprintf(KERN_ERR "error: munmap failed\n");
 	return (err);
diff --git a/src/memory/phys/kmalloc.c b/src/memory/kern/kmalloc.c
similarity index 100%
rename from src/memory/phys/kmalloc.c
rename to src/memory/kern/kmalloc.c
diff --git a/src/memory/phys/krealloc.c b/src/memory/kern/krealloc.c
similarity index 100%
rename from src/memory/phys/krealloc.c
rename to src/memory/kern/krealloc.c
diff --git a/src/memory/phys/ksize.c b/src/memory/kern/ksize.c
similarity index 100%
rename from src/memory/phys/ksize.c
rename to src/memory/kern/ksize.c
diff --git a/src/memory/kern/page.c b/src/memory/kern/page.c
new file mode 100644
index 0000000..51cb559
--- /dev/null
+++ b/src/memory/kern/page.c
@@ -0,0 +1,92 @@
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+
+#include "assert.h"
+#include "kprintf.h"
+#include "memory.h"
+#include "process.h"
+#include "string.h"
+#include "utils.h"
+
+static int16_t find_next_block(size_t nb_pages, uint16_t *pd_index_ptr,
+                               uint32_t **page_table_ptr)
+{
+
+	for (*pd_index_ptr = 769; *pd_index_ptr < 1021; (*pd_index_ptr)++) {
+		if (current_pd[(*pd_index_ptr)] == 0x02) {
+			if (add_page_table(*pd_index_ptr) < 0)
+				return -2;
+		}
+		*page_table_ptr = (uint32_t *)GET_PAGE_ADDR(769, *pd_index_ptr);
+		for (uint16_t i = 0; i + nb_pages - 1 < PT_SIZE; i++) {
+			uint16_t j;
+			for (j = 0; (*page_table_ptr)[i + j] >> 12 == i + j &&
+			            j < nb_pages;
+			     j++)
+				;
+			if (j == nb_pages)
+				return i;
+			i += j;
+		}
+	}
+	return -1;
+}
+
+void *kalloc_pages(size_t size, void **phys_addr)
+{
+	const uint32_t nb_pages = CEIL(size, PAGE_SIZE);
+	uint16_t pd_index;
+	uint32_t *page_table;
+	const int16_t index = find_next_block(nb_pages, &pd_index, &page_table);
+
+	if (index < 0) {
+		kprintf(KERN_CRIT "%d: Not enough pages (max: %d)\n", index,
+		        PT_SIZE);
+		return NULL;
+	}
+	for (size_t i = index; i - (size_t)index < nb_pages; i++) {
+		void *frame = alloc_frame();
+		if (!frame) {
+			for (size_t j = index; j < i; j++)
+				free_frame((void *)(page_table[j] & PAGE_MASK));
+			return NULL;
+		}
+		if (phys_addr)
+			*phys_addr = frame;
+		page_table[i] = ((uint32_t)frame & PAGE_MASK) | INIT_FLAGS;
+	}
+	return (void *)GET_PAGE_ADDR(pd_index, index);
+}
+
+int kfree_pages(void *page_ptr, size_t size)
+{
+	const uint32_t page_addr = (uint32_t)page_ptr;
+	const uint32_t nb_pages = CEIL(size, PAGE_SIZE);
+	const uint32_t page_index = page_addr / PAGE_SIZE;
+	const uint32_t pd_index = page_index / PD_SIZE;
+	const uint32_t pt_index = page_index % PD_SIZE;
+
+	if ((uint32_t)pd_index > 0x300) {
+		kprintf(KERN_WARNING "Address out of range\n");
+		return -1;
+	} else if (page_addr % PAGE_SIZE) {
+		kprintf(KERN_WARNING "Invalid address\n");
+		return -1;
+	} else if (pt_index + nb_pages > PT_SIZE) {
+		kprintf(KERN_WARNING "Invalid number of frames\n");
+		return -1;
+	}
+	uint32_t *page_table =
+	    (uint32_t *)GET_PAGE_ADDR(0, PT_START + pd_index);
+	for (uint16_t i = pt_index; i < pt_index + nb_pages; i++) {
+		if (page_table[i] >> 12 == i) {
+			kprintf(KERN_WARNING "Page already free\n");
+			return -2;
+		}
+		free_frame((void *)(page_table[i] & PAGE_MASK));
+		page_table[i] = i << 12;
+	}
+
+	return 0;
+}
diff --git a/src/memory/load_pd.s b/src/memory/load_pd.s
index bffd31d..ec340f8 100644
--- a/src/memory/load_pd.s
+++ b/src/memory/load_pd.s
@@ -1,12 +1,13 @@
 .intel_syntax noprefix
 
-.text
-.global load_page_directory
+.section .text
+	.global load_page_directory
+
 load_page_directory:
-push ebp
-mov ebp, esp
-mov eax, [esp + 8]
-mov cr3, eax
-mov esp, ebp
-pop ebp
-ret
+	push ebp
+	mov ebp, esp
+	mov eax, [esp + 8]
+	mov cr3, eax
+	mov esp, ebp
+	pop ebp
+	ret
diff --git a/src/memory/memory.c b/src/memory/memory.c
index 1aebc63..6ae92d7 100644
--- a/src/memory/memory.c
+++ b/src/memory/memory.c
@@ -113,7 +113,7 @@ static void init_frame_zones(void)
 
 void init_memory(multiboot_info_t *mbd, uint32_t magic)
 {
-	for (uint16_t i = 0; i < 0x300; i++)
+	for (uint16_t i = 769; i < 1021; i++)
 		kernel_pd[i] = 0x02;
 	init_page_table(page_table_default, 0);
 	kernel_pd[0] = ((uint32_t)page_table_default - HEAP_END) | 0x03;
diff --git a/src/memory/page_directory.c b/src/memory/page_directory.c
index 1699b9b..3e96b0a 100644
--- a/src/memory/page_directory.c
+++ b/src/memory/page_directory.c
@@ -4,4 +4,4 @@ void init_page_directory(uint32_t page_directory[1024])
 {
 	for (uint16_t i = 0; i < 0x300; i++)
 		page_directory[i] = 0x02;
-}
\ No newline at end of file
+}
diff --git a/src/memory/page_table.c b/src/memory/page_table.c
index 9085ca3..916830a 100644
--- a/src/memory/page_table.c
+++ b/src/memory/page_table.c
@@ -1,6 +1,5 @@
-#include "assert.h"
-#include "kprintf.h"
 #include "memory.h"
+
 void init_page_table(uint32_t page_table[1024], uint16_t start)
 {
 	for (uint16_t i = start; i < 1024; i++)
diff --git a/src/memory/paging.s b/src/memory/paging.s
index 10d62d3..354fd8c 100644
--- a/src/memory/paging.s
+++ b/src/memory/paging.s
@@ -1,13 +1,14 @@
 .intel_syntax noprefix
 
-.text
-.global enable_paging
+.section .text
+	.global enable_paging
+
 enable_paging:
-push ebp
-mov ebp, esp
-mov eax, cr0
-or eax, 0x80000000
-mov cr0, eax
-mov esp, ebp
-pop ebp
-ret
+	push ebp
+	mov ebp, esp
+	mov eax, cr0
+	or eax, 0x80000000
+	mov cr0, eax
+	mov esp, ebp
+	pop ebp
+	ret
diff --git a/src/memory/virt/allocator.c b/src/memory/virt/allocator.c
index 853cce0..13f7652 100644
--- a/src/memory/virt/allocator.c
+++ b/src/memory/virt/allocator.c
@@ -3,7 +3,7 @@
 #include "kpanic.h"
 #include "kprintf.h"
 #include "memory.h"
-#include "process.h"
+#include "string.h"
 
 Zone *vzones[3];
 
@@ -50,11 +50,12 @@ static void new_block(Zone *zone, uint32_t zone_size)
 int new_vzone(block_type_t type, uint32_t size)
 {
 	// assert(current_task->pid);
-	void *heap = alloc_pages(size, NULL);
+	void *heap = valloc_pages(size, NULL);
 	if (heap == NULL) {
 		kprintf(KERN_ERR "error: alloc_pages failed\n");
 		return (-1);
 	}
+	memset(heap, 0, size);
 
 	Zone *zone = (Zone *)heap;
 	zone->type = type;
diff --git a/src/memory/page.c b/src/memory/virt/page.c
similarity index 93%
rename from src/memory/page.c
rename to src/memory/virt/page.c
index 7a2c412..0c49f05 100644
--- a/src/memory/page.c
+++ b/src/memory/virt/page.c
@@ -33,7 +33,7 @@ static int16_t find_next_block(size_t nb_pages, uint16_t *pd_index_ptr,
 	return -1;
 }
 
-void *alloc_pages(size_t size, void **phys_addr)
+void *valloc_pages(size_t size, void **phys_addr)
 {
 	const uint32_t nb_pages = CEIL(size, PAGE_SIZE);
 	uint16_t pd_index;
@@ -56,11 +56,10 @@ void *alloc_pages(size_t size, void **phys_addr)
 			*phys_addr = frame;
 		page_table[i] = ((uint32_t)frame & PAGE_MASK) | INIT_FLAGS;
 	}
-	memset((void *)GET_PAGE_ADDR(pd_index, index), 0, nb_pages * PAGE_SIZE);
 	return (void *)GET_PAGE_ADDR(pd_index, index);
 }
 
-int free_pages(void *page_ptr, size_t size)
+int vfree_pages(void *page_ptr, size_t size)
 {
 	const uint32_t page_addr = (uint32_t)page_ptr;
 	const uint32_t nb_pages = CEIL(size, PAGE_SIZE);
diff --git a/src/memory/virt/vfree.c b/src/memory/virt/vfree.c
index 70a3dcf..36bff8c 100644
--- a/src/memory/virt/vfree.c
+++ b/src/memory/virt/vfree.c
@@ -47,7 +47,7 @@ static int unmap_zone(Zone *zone)
 	if (right)
 		right->prev = left;
 unmap:
-	err = free_pages((void *)zone, zone->size);
+	err = vfree_pages((void *)zone, zone->size);
 	if (err)
 		kprintf(KERN_ERR "error: munmap failed\n");
 	return (err);
diff --git a/src/multiboot.c b/src/multiboot.c
index ee9ec16..32fff32 100644
--- a/src/multiboot.c
+++ b/src/multiboot.c
@@ -38,8 +38,8 @@ static void init_vbe(multiboot_info_t *mbd_virt)
 		    ((mbd_virt->framebuffer_addr + i * PAGE_SIZE) & PAGE_MASK) |
 		    INIT_FLAGS;
 	}
-	kernel_pd[800] = ((uint32_t)vbe_page_table - HEAP_END) | 0x03;
-	display.buff = (uint32_t *)GET_PAGE_ADDR(800, 0) +
+	kernel_pd[1021] = ((uint32_t)vbe_page_table - HEAP_END) | 0x03;
+	display.buff = (uint32_t *)GET_PAGE_ADDR(1021, 0) +
 	               (mbd_virt->framebuffer_addr % PAGE_SIZE);
 	display.height = mbd_virt->framebuffer_height;
 	display.width = mbd_virt->framebuffer_width;
diff --git a/src/multitasking/fork.c b/src/multitasking/fork.c
index 6a11c5b..e9d583c 100644
--- a/src/multitasking/fork.c
+++ b/src/multitasking/fork.c
@@ -10,7 +10,7 @@ static struct tcb *thread_clone(struct tcb *thread)
 	if (!new_tcb)
 		return NULL;
 	new_tcb->tid = thread->tid;
-	new_tcb->esp0 = alloc_pages(STACK_SIZE, NULL);
+	new_tcb->esp0 = kalloc_pages(STACK_SIZE, NULL);
 	if (!new_tcb->esp0) {
 		delete_thread(new_tcb);
 		return NULL;
diff --git a/src/multitasking/process.c b/src/multitasking/process.c
index eac4a0c..775fda0 100644
--- a/src/multitasking/process.c
+++ b/src/multitasking/process.c
@@ -9,16 +9,16 @@
 struct pcb *create_process(uid_t uid)
 {
 	static pid_t pid = 1;
-	struct pcb *new_pcb = vmalloc(sizeof(struct pcb));
+	struct pcb *new_pcb = kmalloc(sizeof(struct pcb));
 	if (!new_pcb)
 		return NULL;
 	new_pcb->uid = uid;
 	new_pcb->pid = pid++;
 	new_pcb->tid = 1;
 
-	new_pcb->heap = alloc_pages(4096, &new_pcb->cr3);
+	new_pcb->heap = kalloc_pages(4096, &new_pcb->cr3);
 	if (!new_pcb->heap) {
-		vfree(new_pcb);
+		kfree(new_pcb);
 		return NULL;
 	}
 	memcpy(new_pcb->heap, current_pd, 4096);
@@ -48,8 +48,8 @@ void remove_process(struct pcb *pcb)
 	struct pcb *left = pcb->prev;
 	struct pcb *right = pcb->next;
 	if (pcb->heap)
-		free_pages(pcb->heap, 4096);
+		kfree_pages(pcb->heap, 4096);
 	left->next = right;
 	right->prev = left;
-	vfree(pcb);
+	kfree(pcb);
 }
diff --git a/src/multitasking/thread.c b/src/multitasking/thread.c
index 1f8d4e7..978da94 100644
--- a/src/multitasking/thread.c
+++ b/src/multitasking/thread.c
@@ -10,12 +10,12 @@
 
 struct tcb *create_thread(struct pcb *process, void (*entry)(void))
 {
-	struct tcb *new_tcb = vmalloc(sizeof(struct tcb));
+	struct tcb *new_tcb = kmalloc(sizeof(struct tcb));
 	if (!new_tcb)
 		return NULL;
 	new_tcb->tid = process->tid++;
 
-	new_tcb->esp0 = alloc_pages(STACK_SIZE, NULL);
+	new_tcb->esp0 = kalloc_pages(STACK_SIZE, NULL);
 	if (!new_tcb->esp0) {
 		vfree(new_tcb);
 		return NULL;
@@ -46,9 +46,9 @@ struct tcb *create_thread(struct pcb *process, void (*entry)(void))
 	new_tcb->process = process;
 	new_tcb->state = NEW;
 
-	struct list *new_node = vmalloc(sizeof(struct list));
+	struct list *new_node = kmalloc(sizeof(struct list));
 	if (!new_node) {
-		free_pages(new_tcb->esp0, STACK_SIZE);
+		kfree_pages(new_tcb->esp0, STACK_SIZE);
 		vfree(new_tcb);
 		return NULL;
 	}
@@ -68,13 +68,13 @@ struct tcb *create_thread(struct pcb *process, void (*entry)(void))
 
 void delete_thread(struct tcb *thread)
 {
-	vfree(thread->esp0);
+	kfree(thread->esp0);
 	struct list *it = thread->process->thread_list;
 	assert(it);
 	while (it->next && it->next->content != thread)
 		it = it->next;
 	struct list *to_free = it;
 	it->next = it->next->next;
-	vfree(to_free);
-	vfree(thread);
+	kfree(to_free);
+	kfree(thread);
 }