Kernel: Make better use of the multiboot info.

Define the multiboot info struct properly so we don't have to grab at byte
offsets in the memory access checker code. Also print kernel command line
in init().

1 files changed, 4 insertions, 24 deletions

diff --git a/Kernel/Process.cpp b/Kernel/Process.cpp
index d8d7767241..5b84737ac2 100644
--- a/Kernel/Process.cpp
+++ b/Kernel/Process.cpp
@@ -25,6 +25,7 @@
 #include <Kernel/SharedMemory.h>
 #include <Kernel/ProcessTracer.h>
 #include <Kernel/FileSystem/Custody.h>
+#include <Kernel/Multiboot.h>
 
 //#define DEBUG_POLL_SELECT
 //#define DEBUG_IO
@@ -1433,33 +1434,12 @@ enum class KernelMemoryCheckResult {
     AccessDenied
 };
 
-// FIXME: Nothing about this is really super...
-// This structure is only present at offset 28 in the main multiboot info struct
-// if bit 5 of offset 0 (flags) is set.  We're just assuming that the flag is set.
-//
-// Also, there's almost certainly a better way to get that information here than
-// a global set by boot.S
-//
-// Also I'm not 100% sure any of this is correct...
-
-struct mb_elf {
-    uint32_t num;
-    uint32_t size;
-    uint32_t addr;
-    uint32_t shndx;
-};
-
-extern "C" {
-void* multiboot_ptr;
-}
-
 static KernelMemoryCheckResult check_kernel_memory_access(LinearAddress laddr, bool is_write)
 {
-	// FIXME: It would be better to have a proper structure for this...
-    auto* sections = (const mb_elf*)((const byte*)multiboot_ptr + 28);
+    auto& sections = multiboot_info_ptr->u.elf_sec;
 
-    auto* kernel_program_headers = (Elf32_Phdr*)(sections->addr);
-    for (unsigned i = 0; i < sections->num; ++i) {
+    auto* kernel_program_headers = (Elf32_Phdr*)(sections.addr);
+    for (unsigned i = 0; i < sections.num; ++i) {
         auto& segment = kernel_program_headers[i];
         if (segment.p_type != PT_LOAD || !segment.p_vaddr || !segment.p_memsz)
             continue;