im stoopid and i know it

2 files changed, 257 insertions, 236 deletions

diff --git a/kernel/features/mm.c b/kernel/features/mm.c
index b17d9fc..cde9a94 100644
--- a/kernel/features/mm.c
+++ b/kernel/features/mm.c
@@ -9,21 +9,24 @@
 
 #include <print.h>
 
+static struct page_dir kernel_dir ALIGNED(PAGE_SIZE) = { 0 };
+static struct page_table kernel_tables[256] ALIGNED(PAGE_SIZE) = { 0 };
+
 /**
- * Paging
+ * Lowlevel paging
  */
 
-void paging_disable(void)
+static void paging_disable(void)
 {
 	cr0_set(cr0_get() | 0x7fffffff);
 }
 
-void paging_enable(void)
+static void paging_enable(void)
 {
 	cr0_set(cr0_get() | 0x80000000);
 }
 
-void paging_switch_dir(u32 dir)
+static void paging_switch_dir(u32 dir)
 {
 	assert(dir);
 	cr3_set(dir);
@@ -31,68 +34,131 @@ void paging_switch_dir(u32 dir)
 
 extern void paging_invalidate_tlb(void);
 
+static void page_fault(struct regs *r)
+{
+	// Check error code
+	const char *type = (r->err_code & 4) ? "present" : "non-present";
+	const char *operation = (r->err_code & 2) ? "write" : "read";
+	const char *super = (r->err_code & 1) ? "User" : "Super";
+
+	// Check cr2 address
+	u32 vaddr;
+	__asm__ volatile("movl %%cr2, %%eax" : "=a"(vaddr));
+	struct proc *proc = proc_current();
+	struct page_dir *dir = NULL;
+	if (proc && proc->page_dir) {
+		dir = proc->page_dir;
+		printf("Stack is at %x, entry at %x\n", virtual_to_physical(dir, proc->regs.ebp),
+		       virtual_to_physical(dir, proc->entry));
+	} else {
+		dir = &kernel_dir;
+	}
+	u32 paddr = virtual_to_physical(dir, vaddr);
+
+	// Print!
+	printf("%s process tried to %s a %s page at [vaddr=%x; paddr=%x]\n", super, operation, type,
+	       vaddr, paddr);
+
+	isr_panic(r);
+}
+
 /**
  * Physical
  */
 
 static u32 memory_used = 0;
 static u32 memory_total = 0;
+static u32 best_bet = 0;
 static u8 memory[PAGE_COUNT * PAGE_COUNT / 8] = { 0 };
-#define PHYSICAL_IS_USED(addr)                                                                     \
-	(memory[(u32)(addr) / PAGE_SIZE / 8] & (1 << ((u32)(addr) / PAGE_SIZE % 8)))
 
-#define PHYSICAL_SET_USED(addr)                                                                    \
-	(memory[(u32)(addr) / PAGE_SIZE / 8] |= (1 << ((u32)(addr) / PAGE_SIZE % 8)))
+static u8 physical_page_is_used(u32 addr)
+{
+	u32 page = addr / PAGE_SIZE;
+	return memory[page / 8] & (1 << (page % 8));
+}
+
+static void physical_page_set_used(u32 address)
+{
+	u32 page = address / PAGE_SIZE;
+
+	if (page == best_bet)
+		best_bet++;
 
-#define PHYSICAL_SET_FREE(addr)                                                                    \
-	(memory[(u32)(addr) / PAGE_SIZE / 8] &= ~(1 << ((u32)(addr) / PAGE_SIZE % 8)))
+	memory[page / 8] |= 1 << (page % 8);
+}
 
-u8 physical_is_used(u32 addr, u32 n)
+static void physical_page_set_free(u32 address)
 {
-	for (u32 i = 0; i < n; i++) {
-		if (PHYSICAL_IS_USED(addr + (i * PAGE_SIZE)))
-			return 1;
-	}
-	return 0;
+	u32 page = address / PAGE_SIZE;
+
+	if (page < best_bet)
+		best_bet = page;
+
+	memory[page / 8] &= ~(1 << (page % 8));
 }
 
-void physical_set_used(u32 addr, u32 n)
+static void physical_set_used(struct memory_range range)
 {
-	for (u32 i = 0; i < n; i++) {
-		if (!PHYSICAL_IS_USED(addr + (i * PAGE_SIZE))) {
+	assert(PAGE_ALIGNED(range.base) && PAGE_ALIGNED(range.size));
+
+	for (u32 i = 0; i < range.size / PAGE_SIZE; i++) {
+		u32 addr = range.base + i * PAGE_SIZE;
+		if (!physical_page_is_used(addr)) {
 			memory_used += PAGE_SIZE;
-			PHYSICAL_SET_USED(addr + (i * PAGE_SIZE));
+			physical_page_set_used(addr);
 		}
 	}
 }
 
-void physical_set_free(u32 addr, u32 n)
+static void physical_set_free(struct memory_range range)
 {
-	for (u32 i = 0; i < n; i++) {
-		if (PHYSICAL_IS_USED(addr + (i * PAGE_SIZE))) {
+	assert(PAGE_ALIGNED(range.base) && PAGE_ALIGNED(range.size));
+
+	for (u32 i = 0; i < range.size / PAGE_SIZE; i++) {
+		u32 addr = range.base + i * PAGE_SIZE;
+
+		if (physical_page_is_used(addr)) {
 			memory_used -= PAGE_SIZE;
-			PHYSICAL_SET_FREE(addr + (i * PAGE_SIZE));
+			physical_page_set_free(addr);
 		}
 	}
 }
 
-u32 physical_alloc(u32 n)
+static u8 physical_is_used(struct memory_range range)
 {
-	for (u32 i = 0; i < (memory_total / PAGE_SIZE); i++) {
-		u32 addr = i * PAGE_SIZE;
-		if (!physical_is_used(addr, n)) {
-			physical_set_used(addr, n);
-			return addr;
+	assert(PAGE_ALIGNED(range.base) && PAGE_ALIGNED(range.size));
+
+	for (u32 i = 0; i < range.size / PAGE_SIZE; i++) {
+		u32 addr = range.base + i * PAGE_SIZE;
+
+		if (physical_page_is_used(addr))
+			return 1;
+	}
+
+	return 0;
+}
+
+static struct memory_range physical_alloc(u32 size)
+{
+	assert(PAGE_ALIGNED(size));
+
+	for (u32 i = best_bet; i < ((memory_total - size) / PAGE_SIZE); i++) {
+		struct memory_range range = memory_range(i * PAGE_SIZE, size);
+
+		if (!physical_is_used(range)) {
+			physical_set_used(range);
+			return range;
 		}
 	}
 
 	panic("Out of physical memory!\n");
-	return 0;
+	return memory_range(0, 0);
 }
 
-void physical_free(u32 addr, u32 n)
+static void physical_free(struct memory_range range)
 {
-	physical_set_free(addr, n);
+	assert(PAGE_ALIGNED(range.base) && PAGE_ALIGNED(range.size));
+	physical_set_free(range);
 }
 
 /**
@@ -102,9 +168,6 @@ void physical_free(u32 addr, u32 n)
 #define PDI(vaddr) ((vaddr) >> 22)
 #define PTI(vaddr) (((vaddr) >> 12) & 0x03ff)
 
-static struct page_dir kernel_dir ALIGNED(PAGE_SIZE) = { 0 };
-static struct page_table kernel_tables[256] ALIGNED(PAGE_SIZE) = { 0 };
-
 u8 virtual_present(struct page_dir *dir, u32 vaddr)
 {
 	u32 pdi = PDI(vaddr);
@@ -116,10 +179,8 @@ u8 virtual_present(struct page_dir *dir, u32 vaddr)
 
 	struct page_table *table = (struct page_table *)(dir_entry->bits.address * PAGE_SIZE);
 	union page_table_entry *table_entry = &table->entries[pti];
-	if (!table_entry->bits.present)
-		return 0;
 
-	return 1;
+	return !table_entry->bits.present;
 }
 
 u32 virtual_to_physical(struct page_dir *dir, u32 vaddr)
@@ -139,10 +200,9 @@ u32 virtual_to_physical(struct page_dir *dir, u32 vaddr)
 	return (table_entry->bits.address * PAGE_SIZE) + (vaddr & (PAGE_SIZE - 1));
 }
 
-void memory_alloc_identity(struct page_dir *dir, u32 flags, u32 *out);
-void virtual_map(struct page_dir *dir, u32 vaddr, u32 paddr, u32 n, u8 user)
+void virtual_map(struct page_dir *dir, struct memory_range prange, u32 vaddr, u32 flags)
 {
-	for (u32 i = 0; i < n; i++) {
+	for (u32 i = 0; i < prange.size / PAGE_SIZE; i++) {
 		u32 offset = i * PAGE_SIZE;
 		u32 pdi = PDI(vaddr + offset);
 		u32 pti = PTI(vaddr + offset);
@@ -150,41 +210,42 @@ void virtual_map(struct page_dir *dir, u32 vaddr, u32 paddr, u32 n, u8 user)
 		union page_dir_entry *dir_entry = &dir->entries[pdi];
 		struct page_table *table =
 			(struct page_table *)(dir_entry->bits.address * PAGE_SIZE);
-		union page_table_entry *table_entry = &table->entries[pti];
 
 		if (!dir_entry->bits.present) {
-			memory_alloc_identity(dir, MEMORY_CLEAR, (u32 *)&table);
+			table = memory_alloc_identity(dir, MEMORY_CLEAR);
 			dir_entry->bits.present = 1;
 			dir_entry->bits.writable = 1;
-			dir_entry->bits.user = user;
-			dir_entry->bits.address = (u32)table >> 12;
+			dir_entry->bits.user = 1;
+			dir_entry->bits.address = (u32)(table) >> 12;
 		}
 
+		union page_table_entry *table_entry = &table->entries[pti];
 		table_entry->bits.present = 1;
 		table_entry->bits.writable = 1;
-		table_entry->bits.user = user;
-		table_entry->bits.address = (paddr + offset) >> 12;
+		table_entry->bits.user = flags & MEMORY_USER;
+		table_entry->bits.address = (prange.base + offset) >> 12;
 	}
 
 	paging_invalidate_tlb();
 }
 
-struct memory_range virtual_alloc(struct page_dir *dir, struct memory_range physical_range,
-				  u32 flags)
+struct memory_range virtual_alloc(struct page_dir *dir, struct memory_range prange, u32 flags)
 {
-	u8 is_user = flags & MEMORY_USER;
+	u8 user = flags & MEMORY_USER;
 	u32 vaddr = 0;
 	u32 size = 0;
-	for (u32 i = (is_user ? 256 : 1) * PAGE_COUNT;
-	     i < (is_user ? PAGE_COUNT : 256) * PAGE_COUNT; i++) {
+
+	for (u32 i = (user ? 256 : 1) * PAGE_COUNT; i < (user ? PAGE_COUNT : 256) * PAGE_COUNT;
+	     i++) {
 		u32 addr = i * PAGE_SIZE;
 		if (!virtual_present(dir, addr)) {
 			if (size == 0)
 				vaddr = addr;
+
 			size += PAGE_SIZE;
-			if (size == physical_range.size) {
-				virtual_map(dir, vaddr, physical_range.base,
-					    physical_range.size / PAGE_SIZE, is_user);
+
+			if (size == prange.size) {
+				virtual_map(dir, prange, vaddr, flags);
 				return memory_range(vaddr, size);
 			}
 		} else {
@@ -196,15 +257,18 @@ struct memory_range virtual_alloc(struct page_dir *dir, struct memory_range phys
 	return memory_range(0, 0);
 }
 
-void virtual_free(struct page_dir *dir, struct memory_range virtual_range)
+void virtual_free(struct page_dir *dir, struct memory_range vrange)
 {
-	for (u32 i = 0; i < virtual_range.size / PAGE_SIZE; i++) {
+	for (u32 i = 0; i < vrange.size / PAGE_SIZE; i++) {
 		u32 offset = i * PAGE_SIZE;
 
-		u32 pdi = PDI(virtual_range.base + offset);
-		u32 pti = PTI(virtual_range.base + offset);
+		u32 pdi = PDI(vrange.base + offset);
+		u32 pti = PTI(vrange.base + offset);
 
 		union page_dir_entry *dir_entry = &dir->entries[pdi];
+		if (!dir_entry->bits.present)
+			continue;
+
 		struct page_table *table =
 			(struct page_table *)(dir_entry->bits.address * PAGE_SIZE);
 		union page_table_entry *table_entry = &table->entries[pti];
@@ -216,181 +280,165 @@ void virtual_free(struct page_dir *dir, struct memory_range virtual_range)
 	paging_invalidate_tlb();
 }
 
-/**
- * Memory wrapper
- */
-
-extern u32 kernel_start;
-extern u32 kernel_end;
-
-struct memory_range memory_range_from_address(u32 base, u32 size)
+struct page_dir *virtual_create_dir(void)
 {
-	u32 align = PAGE_SIZE - base % PAGE_SIZE;
+	struct page_dir *dir = memory_alloc(&kernel_dir, sizeof(*dir), MEMORY_CLEAR);
 
-	if (base % PAGE_SIZE == 0) {
-		align = 0;
-	}
+	for (u32 i = 0; i < 256; i++) {
+		union page_dir_entry *dir_entry = &dir->entries[i];
 
-	base += align;
-	size -= align;
+		dir_entry->bits.user = 0;
+		dir_entry->bits.writable = 1;
+		dir_entry->bits.present = 1;
+		dir_entry->bits.address = (u32)&kernel_tables[i] / PAGE_SIZE;
+	}
 
-	size -= size % PAGE_SIZE;
+	return dir;
+}
 
-	return memory_range(base, size);
+struct page_dir *virtual_kernel_dir(void)
+{
+	return &kernel_dir;
 }
 
-struct memory_range memory_range_around_address(u32 base, u32 size)
+void virtual_destroy_dir(struct page_dir *dir)
 {
-	u32 align = base % PAGE_SIZE;
+	assert(dir != &kernel_dir);
 
-	base -= align;
-	size += align;
+	for (u32 i = 256; i < PAGE_COUNT; i++) {
+		union page_dir_entry *dir_entry = &dir->entries[i];
+		if (dir_entry->bits.present) {
+			struct page_table *table =
+				(struct page_table *)(dir_entry->bits.address * PAGE_SIZE);
+			for (u32 j = 0; j < PAGE_COUNT; j++) {
+				union page_table_entry *table_entry = &table->entries[j];
+				if (table_entry->bits.present) {
+					u32 paddr = table_entry->bits.address * PAGE_SIZE;
+					physical_free(memory_range(paddr, PAGE_SIZE));
+				}
+			}
 
-	size += PAGE_SIZE - size % PAGE_SIZE;
+			memory_free(&kernel_dir, memory_range((u32)table, sizeof(*table)));
+		}
+	}
 
-	return memory_range(base, size);
+	memory_free(&kernel_dir, memory_range((u32)dir, sizeof(*dir)));
 }
 
-static struct memory_range kernel_memory_range(void)
-{
-	return memory_range_around_address((u32)&kernel_start,
-					   (u32)&kernel_end - (u32)&kernel_start);
-}
+/**
+ * Memory wrappers
+ */
 
-void memory_map_identity(struct page_dir *dir, struct memory_range range, u32 flags)
+void *memory_alloc(struct page_dir *dir, u32 size, u32 flags)
 {
-	assert(PAGE_ALIGNED(range.base) && PAGE_ALIGNED(range.size));
+	assert(PAGE_ALIGNED(size));
 
-	u32 page_count = range.size / PAGE_SIZE;
-	physical_set_used(range.base, page_count);
-	virtual_map(dir, range.base, range.base, page_count, flags & MEMORY_USER);
-
-	if (flags & MEMORY_CLEAR)
-		memset((void *)range.base, 0, range.size);
-}
+	if (!size)
+		return 0;
 
-void memory_map(struct page_dir *dir, struct memory_range range, u32 flags)
-{
-	assert(PAGE_ALIGNED(range.base) && PAGE_ALIGNED(range.size));
+	struct memory_range prange = physical_alloc(size);
+	if (prange.size == 0)
+		return 0;
 
-	for (u32 i = 0; i < range.size / PAGE_SIZE; i++) {
-		u32 vaddr = range.base + i * PAGE_SIZE;
-		if (!virtual_present(dir, vaddr)) {
-			u32 paddr = physical_alloc(1);
-			virtual_map(dir, vaddr, paddr, 1, flags & MEMORY_USER);
-		}
+	u32 vaddr = virtual_alloc(dir, prange, flags).base;
+	if (!vaddr) {
+		physical_free(prange);
+		return 0;
 	}
 
 	if (flags & MEMORY_CLEAR)
-		memset((void *)range.base, 0, range.size);
+		memset((void *)vaddr, 0, size);
+
+	return (void *)vaddr;
 }
 
-void memory_alloc_identity(struct page_dir *dir, u32 flags, u32 *out)
+void *memory_alloc_identity(struct page_dir *dir, u32 flags)
 {
 	for (u32 i = 1; i < 256 * PAGE_COUNT; i++) {
-		u32 addr = i * PAGE_SIZE;
-		if (!virtual_present(dir, addr) && !physical_is_used(addr, 1)) {
-			physical_set_used(addr, 1);
-			virtual_map(dir, addr, addr, 1, flags & MEMORY_USER);
+		struct memory_range range = memory_range(i * PAGE_SIZE, PAGE_SIZE);
 
+		if (!virtual_present(dir, range.base) && !physical_is_used(range)) {
+			physical_set_used(range);
+			virtual_map(dir, range, range.base, flags);
 			if (flags & MEMORY_CLEAR)
-				memset((void *)addr, 0, PAGE_SIZE);
-
-			*out = addr;
-
-			return;
+				memset((void *)range.base, 0, PAGE_SIZE);
+			return (void *)range.base;
 		}
 	}
 
-	*out = 0;
-	panic("Out of memory!\n");
-}
-
-void memory_alloc(struct page_dir *dir, u32 size, u32 flags, u32 *out)
-{
-	assert(size && PAGE_ALIGNED(size));
-	*out = 0;
-
-	u32 page_count = size / PAGE_SIZE;
-	u32 paddr = physical_alloc(page_count);
-	assert(paddr);
-	u32 vaddr = virtual_alloc(dir, memory_range(paddr, size), flags).base;
-	assert(vaddr);
-	if (flags & MEMORY_CLEAR)
-		memset((void *)vaddr, 0, page_count * PAGE_SIZE);
-	*out = vaddr;
+	return 0;
 }
 
-void memory_free(struct page_dir *dir, struct memory_range range)
+void memory_free(struct page_dir *dir, struct memory_range vrange)
 {
-	assert(PAGE_ALIGNED(range.base) && PAGE_ALIGNED(range.size));
+	assert(PAGE_ALIGNED(vrange.base) && PAGE_ALIGNED(vrange.size));
 
-	for (u32 i = 0; i < range.size / PAGE_SIZE; i++) {
-		u32 vaddr = range.base + i * PAGE_SIZE;
+	for (u32 i = 0; i < vrange.size / PAGE_SIZE; i++) {
+		u32 vaddr = vrange.base + i * PAGE_SIZE;
 		if (virtual_present(dir, vaddr)) {
-			physical_free(virtual_to_physical(dir, vaddr), 1);
-			virtual_free(dir, memory_range(vaddr, PAGE_SIZE));
+			struct memory_range page_prange =
+				memory_range(virtual_to_physical(dir, vaddr), PAGE_SIZE);
+			struct memory_range page_vrange = memory_range(vaddr, PAGE_SIZE);
+			physical_free(page_prange);
+			virtual_free(dir, page_vrange);
 		}
 	}
 }
 
-struct page_dir *memory_dir_create(void)
+void memory_map_identity(struct page_dir *dir, struct memory_range prange, u32 flags)
 {
-	struct page_dir *dir = NULL;
-	memory_alloc(&kernel_dir, sizeof(*dir), MEMORY_CLEAR, (u32 *)&dir);
-	memset(dir, 0, sizeof(*dir));
+	assert(PAGE_ALIGNED(prange.base) && PAGE_ALIGNED(prange.size));
 
-	for (u32 i = 0; i < 256; i++) {
-		union page_dir_entry *entry = &dir->entries[i];
-		entry->bits.present = 1;
-		entry->bits.writable = 1;
-		entry->bits.user = 0;
-		entry->bits.address = (u32)&kernel_tables[i] / PAGE_SIZE;
-	}
+	physical_set_used(prange);
+	virtual_map(dir, prange, prange.base, flags);
+	if (flags & MEMORY_CLEAR)
+		memset((void *)prange.base, 0, prange.size);
+}
 
-	return dir;
+void memory_switch_dir(struct page_dir *dir)
+{
+	paging_switch_dir(virtual_to_physical(&kernel_dir, (u32)dir));
 }
 
-void memory_dir_destroy(struct page_dir *dir)
+struct memory_range memory_range_from(u32 base, u32 size)
 {
-	for (u32 i = 256; i < PAGE_COUNT; i++) {
-		union page_dir_entry *dir_entry = &dir->entries[i];
-		if (dir_entry->bits.present) {
-			struct page_table *table =
-				(struct page_table *)(dir_entry->bits.address * PAGE_SIZE);
-			for (u32 j = 0; j < PAGE_COUNT; j++) {
-				union page_table_entry *table_entry = &table->entries[j];
-				if (table_entry->bits.present)
-					physical_free(table_entry->bits.address * PAGE_SIZE, 1);
-			}
+	u32 align = PAGE_SIZE - base % PAGE_SIZE;
 
-			memory_free(&kernel_dir, memory_range((u32)table, sizeof(*table)));
-		}
+	if (base % PAGE_SIZE == 0) {
+		align = 0;
 	}
-	memory_free(&kernel_dir, memory_range((u32)dir, sizeof(*dir)));
+
+	base += align;
+	size -= align;
+
+	size -= size % PAGE_SIZE;
+
+	return memory_range(base, size);
 }
 
-void memory_dir_switch(struct page_dir *dir)
+struct memory_range memory_range_around(u32 base, u32 size)
 {
-	paging_switch_dir(virtual_to_physical(&kernel_dir, (u32)dir));
+	u32 align = base % PAGE_SIZE;
+
+	base -= align;
+	size += align;
+
+	size += PAGE_SIZE - size % PAGE_SIZE;
+
+	return memory_range(base, size);
 }
 
-struct page_dir *memory_kernel_dir(void)
+extern u32 kernel_start;
+extern u32 kernel_end;
+static struct memory_range kernel_memory_range(void)
 {
-	return &kernel_dir;
+	return memory_range_around((u32)&kernel_start, (u32)&kernel_end - (u32)&kernel_start);
 }
 
-void memory_initialize(struct mem_info *mem_info)
+void memory_install(struct mem_info *mem_info)
 {
-	for (u32 i = 0; i < 256; i++) {
-		union page_dir_entry *entry = &kernel_dir.entries[i];
-		entry->bits.present = 1;
-		entry->bits.writable = 1;
-		entry->bits.user = 0;
-		entry->bits.address = (u32)&kernel_tables[i] / PAGE_SIZE;
-	}
+	heap_init(HEAP_START);
 
-	// Detect memory using E820 memory map
 	for (struct mmap_boot *p = mem_info->start; (u32)(p - mem_info->start) < mem_info->size;
 	     p++) {
 		if (p->hbase || !p->acpi || !p->type)
@@ -402,13 +450,21 @@ void memory_initialize(struct mem_info *mem_info)
 
 		/* printf("Memory region: %x-%x\n", p->lbase, p->lbase + size); */
 		if (p->type == MEMORY_AVAILABLE) {
-			physical_set_free(p->lbase, size / PAGE_SIZE);
+			physical_set_free(memory_range_around(p->lbase, size / PAGE_SIZE));
 			memory_total += size;
 		} else if (p->type == MEMORY_DEFECT) {
 			printf("Defect memory at 0x%x-0x%x!\n", p->lbase, p->lbase + size);
 		}
 	}
 
+	for (u32 i = 0; i < 256; i++) {
+		union page_dir_entry *dir_entry = &kernel_dir.entries[i];
+		dir_entry->bits.present = 1;
+		dir_entry->bits.writable = 1;
+		dir_entry->bits.user = 0;
+		dir_entry->bits.address = (u32)&kernel_tables[i] / PAGE_SIZE;
+	}
+
 	memory_used = 0;
 	printf("Detected memory: %dKiB (%dMiB)\n", memory_total >> 10, memory_total >> 20);
 
@@ -416,56 +472,23 @@ void memory_initialize(struct mem_info *mem_info)
 	memory_map_identity(&kernel_dir, kernel_memory_range(), MEMORY_NONE);
 
 	// Map kernel stack
-	memory_map_identity(&kernel_dir,
-			    memory_range_around_address(STACK_START - STACK_SIZE, STACK_SIZE),
+	memory_map_identity(&kernel_dir, memory_range_around(STACK_START - STACK_SIZE, STACK_SIZE),
 			    MEMORY_NONE);
 
 	// Map kernel heap
-	memory_map_identity(&kernel_dir, memory_range_around_address(HEAP_START, HEAP_INIT_SIZE),
+	memory_map_identity(&kernel_dir, memory_range_around(HEAP_START, HEAP_INIT_SIZE),
 			    MEMORY_NONE);
 
 	// TODO: Triple fault prevention? Probably bootloader stuff or something
-	memory_map_identity(&kernel_dir, memory_range_around_address(0x7000, 0x1000), MEMORY_NONE);
+	memory_map_identity(&kernel_dir, memory_range_around(0x7000, 0x1000), MEMORY_NONE);
 
 	// Unmap NULL byte/page
-	virtual_free(&kernel_dir, memory_range(0, PAGE_SIZE));
-	physical_set_used(0, 1);
+	struct memory_range zero = memory_range(0, PAGE_SIZE);
+	virtual_free(&kernel_dir, zero);
+	physical_set_used(zero);
 
-	memory_dir_switch(&kernel_dir);
+	memory_switch_dir(&kernel_dir);
 	paging_enable();
-}
 
-static void page_fault(struct regs *r)
-{
-	// Check error code
-	const char *type = (r->err_code & 4) ? "present" : "non-present";
-	const char *operation = (r->err_code & 2) ? "write" : "read";
-	const char *super = (r->err_code & 1) ? "User" : "Super";
-
-	// Check cr2 address
-	u32 vaddr;
-	__asm__ volatile("movl %%cr2, %%eax" : "=a"(vaddr));
-	struct proc *proc = proc_current();
-	struct page_dir *dir = NULL;
-	if (proc && proc->page_dir) {
-		dir = proc->page_dir;
-		printf("Stack is at %x, entry at %x\n", virtual_to_physical(dir, proc->regs.ebp),
-		       virtual_to_physical(dir, proc->entry));
-	} else {
-		dir = &kernel_dir;
-	}
-	u32 paddr = virtual_to_physical(dir, vaddr);
-
-	// Print!
-	printf("%s process tried to %s a %s page at [vaddr=%x; paddr=%x]\n", super, operation, type,
-	       vaddr, paddr);
-
-	isr_panic(r);
-}
-
-void paging_install(struct mem_info *mem_info)
-{
-	memory_initialize(mem_info);
-	heap_init(HEAP_START);
 	isr_install_handler(14, page_fault);
 }
diff --git a/kernel/inc/mm.h b/kernel/inc/mm.h
index e680ab7..6d3714d 100644
--- a/kernel/inc/mm.h
+++ b/kernel/inc/mm.h
@@ -6,12 +6,15 @@
 #include <boot.h>
 #include <def.h>
 
+struct memory_range {
+	u32 base;
+	u32 size;
+};
+
 /**
  * Physical
  */
 
-u32 physical_alloc(u32 n);
-
 /**
  * Virtual
  */
@@ -66,10 +69,11 @@ struct page_dir {
 } PACKED;
 
 u32 virtual_to_physical(struct page_dir *dir, u32 vaddr);
-void virtual_map(struct page_dir *dir, u32 vaddr, u32 paddr, u32 n, u8 user);
+void virtual_map(struct page_dir *dir, struct memory_range prange, u32 vaddr, u32 flags);
 struct memory_range virtual_alloc(struct page_dir *dir, struct memory_range physical_range,
 				  u32 flags);
-void paging_install(struct mem_info *mem_info);
+struct page_dir *virtual_create_dir(void);
+struct page_dir *virtual_kernel_dir(void);
 
 /**
  * Memory wrappers
@@ -80,19 +84,13 @@ void paging_install(struct mem_info *mem_info);
 #define MEMORY_CLEAR (1 << 1)
 #define memory_range(base, size) ((struct memory_range){ (base), (size) })
 
-struct memory_range {
-	u32 base;
-	u32 size;
-};
-
-struct memory_range memory_range_from_address(u32 base, u32 size);
-struct memory_range memory_range_around_address(u32 base, u32 size);
+struct memory_range memory_range_from(u32 base, u32 size);
+struct memory_range memory_range_around(u32 base, u32 size);
 
-struct page_dir *memory_dir_create(void);
-void memory_dir_switch(struct page_dir *dir);
-// TODO: Remove these wrappers completely?
-/* void memory_alloc(struct page_dir *dir, u32 size, u32 flags, u32 *out); */
-/* void memory_map(struct page_dir *dir, struct memory_range range, u32 flags); */
-struct page_dir *memory_kernel_dir(void);
+void memory_install(struct mem_info *mem_info);
+void *memory_alloc(struct page_dir *dir, u32 size, u32 flags);
+void *memory_alloc_identity(struct page_dir *dir, u32 flags);
+void memory_free(struct page_dir *dir, struct memory_range vrange);
+void memory_switch_dir(struct page_dir *dir);
 
 #endif