amd64: barely boot into kernel code

1 files changed, 0 insertions, 206 deletions

diff --git a/src/kernel/arch/i386/pagedir.c b/src/kernel/arch/i386/pagedir.c
deleted file mode 100644
index e607cc7..0000000
--- a/src/kernel/arch/i386/pagedir.c
+++ /dev/null
@@ -1,206 +0,0 @@
-#include <kernel/arch/generic.h>
-#include <kernel/mem/alloc.h>
-#include <shared/mem.h>
-#include <stdint.h>
-
-/* <heat> nitpick: I highly recommend you dont use bitfields for paging
- *        structures
- * <heat> you can't change them atomically and the way they're layed out
- *        in memory is implementation defined iirc
- */
-struct pagetable_entry {
-	uint32_t present   : 1;
-	uint32_t writeable : 1;
-	uint32_t user      : 1;
-	uint32_t writethru : 1;
-	uint32_t uncached  : 1;
-	uint32_t dirty     : 1;
-	uint32_t always0   : 1; // memory type thing?
-	uint32_t global    : 1;
-	uint32_t _unused   : 3;
-	uint32_t address   : 21;
-};
-
-struct pagedir_entry {
-	uint32_t present   : 1;
-	uint32_t _writeable: 1; // don't use! not checked by multiple functions here
-	uint32_t _user     : 1; // ^
-	uint32_t writethru : 1;
-	uint32_t uncached  : 1;
-	uint32_t accessed  : 1;
-	uint32_t always0   : 1;
-	uint32_t large     : 1; // 4 MiB instead of 4 KiB
-	uint32_t _unused   : 3;
-	uint32_t address   : 21;
-} __attribute__((packed));
-
-struct pagedir {
-	struct pagedir_entry e[1024];
-} __attribute__((packed));
-
-
-struct pagedir *pagedir_new(void) {
-	struct pagedir *dir = page_alloc(1);
-	for (int i = 0; i < 1024; i++)
-		dir->e[i].present = 0;
-	return dir;
-}
-
-void pagedir_free(struct pagedir *dir) {
-	// assumes all user pages are unique and can be freed
-	struct pagetable_entry *pt;
-	void *page;
-
-	for (int i = 0; i < 1024; i++) {
-		if (!dir->e[i].present) continue;
-
-		pt = (void*)(dir->e[i].address << 11);
-
-		for (int j = 0; j < 1024; j++) {
-			if (!pt[j].present) continue;
-			if (!pt[j].user)    continue;
-
-			page = (void*)(pt[j].address << 11);
-			page_free(page, 1);
-		}
-		page_free(pt, 1);
-	}
-	page_free(dir, 1);
-}
-
-static struct pagetable_entry*
-get_entry(struct pagedir *dir, const void __user *virt) {
-	uint32_t pd_idx = ((uintptr_t)virt) >> 22;
-	uint32_t pt_idx = ((uintptr_t)virt) >> 12 & 0x03FF;
-	struct pagetable_entry *pagetable;
-
-	if (!dir->e[pd_idx].present) return NULL;
-
-	pagetable = (void*)(dir->e[pd_idx].address << 11);
-	return &pagetable[pt_idx];
-}
-
-void *pagedir_unmap(struct pagedir *dir, void __user *virt) {
-	void *phys = pagedir_virt2phys(dir, virt, false, false);
-	struct pagetable_entry *page = get_entry(dir, virt);
-	page->present = false;
-	return phys;
-}
-
-void pagedir_map(struct pagedir *dir, void __user *virt, void *phys,
-                 bool user, bool writeable)
-{
-	uintptr_t virt_cast = (uintptr_t) virt;
-	uint32_t pd_idx = virt_cast >> 22;
-	uint32_t pt_idx = virt_cast >> 12 & 0x03FF;
-	struct pagetable_entry *pagetable;
-
-	if (dir->e[pd_idx].present) {
-		pagetable = (void*) (dir->e[pd_idx].address << 11);
-	} else {
-		pagetable = page_alloc(1);
-		for (int i = 0; i < 1024; i++)
-			pagetable[i].present = 0;
-
-		dir->e[pd_idx] = (struct pagedir_entry) {
-			.present   = 1,
-			._writeable= 1,
-			._user     = 1,
-			.writethru = 1,
-			.uncached  = 0,
-			.accessed  = 0,
-			.always0   = 0,
-			.large     = 0,
-			._unused   = 0,
-			.address   = (uintptr_t) pagetable >> 11
-		};
-	}
-
-	pagetable[pt_idx] = (struct pagetable_entry) {
-		.present   = 1,
-		.writeable = writeable,
-		.user      = user,
-		.writethru = 1,
-		.uncached  = 0,
-		.dirty     = 0,
-		.always0   = 0,
-		.global    = 0,
-		._unused   = 0,
-		.address   = (uintptr_t) phys >> 11
-	};
-}
-
-void pagedir_switch(struct pagedir *dir) {
-	asm volatile("mov %0, %%cr3;" : : "r" (dir) : "memory");
-}
-
-// creates a new pagedir with exact copies of the user pages
-struct pagedir *pagedir_copy(const struct pagedir *orig) {
-	struct pagedir *clone = page_alloc(1);
-	struct pagetable_entry *orig_pt, *clone_pt;
-	void *orig_page, *clone_page;
-
-	for (int i = 0; i < 1024; i++) {
-		clone->e[i] = orig->e[i];
-		if (!orig->e[i].present) continue;
-
-		orig_pt = (void*)(orig->e[i].address << 11);
-		clone_pt = page_alloc(1);
-		clone->e[i].address = (uintptr_t) clone_pt >> 11;
-
-		for (int j = 0; j < 1024; j++) {
-			clone_pt[j] = orig_pt[j];
-			if (!orig_pt[j].present) continue;
-			if (!orig_pt[j].user)    continue;
-			// i could use .global?
-
-			orig_page = (void*)(orig_pt[j].address << 11);
-			clone_page = page_alloc(1);
-			clone_pt[j].address = (uintptr_t) clone_page >> 11;
-
-			memcpy(clone_page, orig_page, PAGE_SIZE);
-		}
-	}
-
-	return clone;
-}
-
-bool pagedir_iskern(struct pagedir *dir, const void __user *virt) {
-	struct pagetable_entry *page = get_entry(dir, virt);
-	return page && page->present && !page->user;
-}
-
-void *pagedir_virt2phys(struct pagedir *dir, const void __user *virt,
-                        bool user, bool writeable)
-{
-	struct pagetable_entry *page;
-	uintptr_t phys;
-	page = get_entry(dir, virt);
-	if (!page || !page->present) return NULL;
-	if (user && !page->user) return NULL;
-	if (writeable && !page->writeable) return NULL;
-
-	phys  = page->address << 11;
-	phys |= ((uintptr_t)virt) & 0xFFF;
-	return (void*)phys;
-}
-
-void __user *pagedir_findfree(struct pagedir *dir, char __user *start, size_t len) {
-	struct pagetable_entry *page;
-	char __user *iter;
-	start = (userptr_t)(((uintptr_t __force)start + PAGE_MASK) & ~PAGE_MASK); // round up to next page
-	iter = start;
-
-	while (iter < (char __user *)0xFFF00000) { // TODO better boundary
-		page = get_entry(dir, iter);
-		if (page && page->present) {
-			start = iter + PAGE_SIZE;
-		} else {
-			if ((size_t)(iter + PAGE_SIZE - start) >= len)
-				return start;
-		}
-		iter += PAGE_SIZE;
-	}
-
-	return NULL;
-}