refactor, new arch dirs, (wip) page alloc on write, hsv screen (convert to userspace later), other fixes

1 files changed, 74 insertions, 8 deletions

diff --git a/src/arch/amd64/paging.c b/src/arch/amd64/paging.c
index 604e0a0..1c1c56c 100644
--- a/src/arch/amd64/paging.c
+++ b/src/arch/amd64/paging.c
@@ -45,7 +45,8 @@ struct pde {
 // PAGE TABLE ENTRY
 struct pte {
 	uint64_t flags              : 9;
-	uint64_t                    : 3;
+	uint64_t loaded             : 1;
+	uint64_t                    : 2;
 	uint64_t address            : 40;
 	uint64_t                    : 7;
 	uint64_t protection_key     : 4;
@@ -69,7 +70,7 @@ static struct pde   *pd_mapped   = (void *) (uintptr_t) 0x202000;
 static struct pte   *pt_mapped   = (void *) (uintptr_t) 0x203000;
 
 static inline void invlpg(void *addr) {
-	__asm volatile("invlpg (%0)" ::"r" (addr) : "memory");
+	__asm__ volatile("invlpg (%0)" ::"r" (addr) : "memory");
 }
 
 static void load_addr(void *phys_addr) {
@@ -297,6 +298,7 @@ static void unmap_page(
 
 	page->address = 0;
 	page->flags = 0;
+	page->loaded = 0;
 
 	try_unmap_pt();
 
@@ -360,6 +362,7 @@ static void unmap_pages(
 
 		page->address = 0;
 		page->flags = 0;
+		page->loaded = 0;
 
 	}
 
@@ -369,6 +372,31 @@ static void unmap_pages(
 	return;
 }
 
+static struct pte *get_page(
+		struct pml4e *root,
+		void *virt
+) {
+	struct pdpte *pdpt;
+	struct pde   *pd;
+	struct pte   *pt;
+	struct pte   *page;
+
+	unsigned int df = 0;
+
+	if (select_pdpt(virt, df, root, &pdpt, false))
+		return NULL;
+
+	if (select_pd(virt, df, pdpt, &pd, false))
+		return NULL;
+
+	if (select_pt(virt, df, pd, &pt, false))
+		return NULL;
+
+	select_page(virt, pt, &page);
+
+	return page;
+}
+
 static int map_page(
 		struct pml4e *root,
 		void *virt,
@@ -382,6 +410,9 @@ static int map_page(
 
 	unsigned int df = F_WRITEABLE;
 
+	if (phys == NULL)
+		df = 0; // alloc page on fault
+
 	if (select_pdpt(virt, df, root, &pdpt, true))
 		return 1;
 
@@ -393,9 +424,16 @@ static int map_page(
 
 	select_page(virt, pt, &page);
 
-	page->address = (uint64_t)phys >> 12;
-	page->flags = F_PRESENT | flags;
-	invlpg(virt);
+	if (phys) {
+		page->flags = F_PRESENT | flags;
+		page->address = (uint64_t)phys >> 12;
+		page->loaded = 1;
+		invlpg(virt);
+	} else {
+		page->flags = flags;
+		page->address = 0;
+		page->loaded = 0;
+	}
 
 	return 0;
 }
@@ -424,6 +462,9 @@ static int map_pages(
 
 	unsigned int df = F_WRITEABLE;
 
+	if (phys_start == NULL)
+		df = 0; // alloc page on fault
+
 	long i;
 	for (i = 0; i < page_count; i++) {
 
@@ -454,15 +495,22 @@ static int map_pages(
 
 		select_page(virt, pt, &page);
 
-		page->address = (uint64_t)phys >> 12;
-		page->flags = F_PRESENT | flags;
+		if (phys_start) {
+			page->flags = F_PRESENT | flags;
+			page->address = (uint64_t)phys >> 12;
+			page->loaded = 1;
+		} else {
+			page->flags = flags;
+			page->address = 0;
+			page->loaded = 0;
+		}
 
 		if (flags & F_GLOBAL)
 			invlpg(virt);
 
 	}
 
-	__asm volatile("mov %cr3, %rax; mov %rax, %cr3;");
+	__asm__ volatile("mov %cr3, %rax; mov %rax, %cr3;");
 
 	return 0;
 
@@ -575,3 +623,21 @@ int kunmap_page(void *virt_addr) {
 	unmap_page(kernel_pml4, virt_addr);
 	return 0;
 }
+
+int kload_page(void *virt_addr) {
+	struct pte *page = get_page(kernel_pml4, virt_addr);
+	if (page == NULL)
+		return -1;
+	if (page->loaded)
+		return -1;
+	void *phys = alloc_phys_page();
+	kprintf("0x%p\n", phys);
+	if (phys == NULL)
+		return -2;
+	page->loaded = 1;
+	page->address = (uint64_t)phys >> 12;
+	page->flags |= F_PRESENT | F_WRITEABLE;
+	invlpg(virt_addr);
+	__asm__ volatile ("movq %cr3, %rax; movq %rax, %cr3;");
+	return 0;
+}