terrible hack to not overwrite mboot data

2 files changed, 32 insertions, 3 deletions

diff --git a/kernel/mboot/mboot.c b/kernel/mboot/mboot.c
index e4547e7..8163f04 100644
--- a/kernel/mboot/mboot.c
+++ b/kernel/mboot/mboot.c
@@ -5,6 +5,8 @@
 
 static volatile void *mboot = NULL;
 
+extern char kernel_end[];
+
 void mboot_init(long magic, volatile void *ptr)
 {
 	if (magic != MULTIBOOT2_BOOTLOADER_MAGIC)
@@ -12,6 +14,23 @@ void mboot_init(long magic, volatile void *ptr)
 	mboot = ptr;
 }
 
+void *mboot_end(void)
+{
+	if (mboot == NULL)
+		return NULL;
+
+	struct multiboot *info = (struct multiboot *)mboot;
+	uintptr_t mboot_end, initrd_end;
+	size_t initrd_len;
+
+	mboot_end = (uintptr_t)info + info->total_size;
+	initrd_end = (uintptr_t)mboot_get_initrd_phys(&initrd_len);
+	if (initrd_end)
+		initrd_end += initrd_len;
+
+	return (void *)MAX(mboot_end, initrd_end);
+}
+
 void *locate_mboot_table(uint32_t type)
 {
 	if (mboot == NULL)
diff --git a/kernel/mboot/module.c b/kernel/mboot/module.c
index bf15eca..03c5147 100644
--- a/kernel/mboot/module.c
+++ b/kernel/mboot/module.c
@@ -1,4 +1,4 @@
-#include "comus/memory.h"
+#include <comus/memory.h>
 #include <comus/mboot.h>
 
 #include "mboot.h"
@@ -16,7 +16,7 @@ struct multiboot_tag_module {
 static void *mapped_addr = NULL;
 size_t initrd_len;
 
-void *mboot_get_initrd(size_t *len)
+void *mboot_get_initrd_phys(size_t *len)
 {
 	struct multiboot_tag_module *mod;
 	void *tag, *phys;
@@ -36,11 +36,21 @@ void *mboot_get_initrd(size_t *len)
 	phys = (void *)(uintptr_t)mod->mod_start;
 	initrd_len = mod->mod_end - mod->mod_start;
 
+	*len = initrd_len;
+	return phys;
+}
+
+void *mboot_get_initrd(size_t *len)
+{
+	// get phys
+	void *phys = mboot_get_initrd_phys(len);
+	if (phys == NULL)
+		return NULL;
+
 	// map addr
 	mapped_addr = kmapaddr(phys, NULL, initrd_len, F_PRESENT | F_WRITEABLE);
 	if (mapped_addr == NULL)
 		return NULL;
 
-	*len = initrd_len;
 	return mapped_addr;
 }