Split RAM initialization into function.

[pintos-anon] / src / threads / init.c

diff --git a/src/threads/init.c b/src/threads/init.c
index 3eb45add76b9a74a4828648974a83fde4ae7f00a..63ec7fa94a36ffe3f0d027d21f3f1eedd1b84096 100644 (file)
--- a/src/threads/init.c
+++ b/src/threads/init.c
@@ -7,6 +7,7 @@
 #include "io.h"
 #include "kbd.h"
 #include "lib.h"
+#include "loader.h"
 #include "malloc.h"
 #include "mmu.h"
 #include "paging.h"
@@ -18,6 +19,7 @@
 #include "vga.h"
 #ifdef FILESYS
 #include "filesys.h"
+#include "disk.h"
 #endif
 
 /* Size of kernel static code and data, in 4 kB pages. */
@@ -26,54 +28,53 @@ size_t kernel_pages;
 /* Amount of physical memory, in 4 kB pages. */
 size_t ram_pages;
 
+static void ram_init (void);
 static void gdt_init (void);
+static void argv_init (void);
 void power_off (void);
 
 static void
 main_thread (void *aux UNUSED) 
 {
-  thread_execute ("a.out");
+  disk_init ();
+
+#ifdef FILESYS
+  filesys_init (true);
+#endif
+  filesys_self_test ();
 }
 
 int
 main (void)
 {
-  extern char _text, _end, __bss_start;
   struct thread *t;
 
-  /* Clear out the BSS segment. */
-  memset (&__bss_start, 0, &_end - &__bss_start);
-
+  /* Initialize components needed by printk() very early. */
+  ram_init ();
   vga_init ();
   serial_init ();
+  printk ("Booting cnachos86...\n");
 
   /* Calculate how much RAM the kernel uses, and find out from
      the bootloader how much RAM this machine has. */
-  kernel_pages = (&_end - &_text + 4095) / 4096;
-  ram_pages = *(uint32_t *) (0x7e00 - 8);
-
-  printk ("Initializing nachos-x86, %d kB RAM detected.\n",
-          ram_pages * 4);
+  printk ("ram: detected %'d kB main memory.\n", ram_pages * 4);
 
   /* Memory from the end of the kernel through the end of memory
      is free.  Give it to the page allocator. */
-  palloc_init ((void *) (KERN_BASE + kernel_pages * PGSIZE),
-               (void *) (PHYS_BASE + ram_pages * PGSIZE));
+  palloc_init (ptov (LOADER_KERN_BASE + kernel_pages * PGSIZE),
+               ptov (ram_pages * PGSIZE));
   paging_init ();
   gdt_init ();
 
   malloc_init ();
   random_init ();
 
+  argv_init ();
+
   intr_init ();
   timer_init ();
   kbd_init ();
 
-#ifdef FILESYS
-  filesys_init (false);
-  filesys_self_test ();
-#endif
-
   thread_init ();
 
   t = thread_create ("main", main_thread, NULL);
@@ -94,13 +95,13 @@ make_seg_desc (uint32_t base,
   uint32_t e0 = ((limit & 0xffff)             /* Limit 15:0. */
                  | (base << 16));             /* Base 15:0. */
   uint32_t e1 = (((base >> 16) & 0xff)        /* Base 23:16. */
-                 | ( system << 12)  /* 0=system, 1=code/data. */
-                 | ( type << 8)     /* Segment type. */
+                 | (system << 12)             /* 0=system, 1=code/data. */
+                 | (type << 8)                /* Segment type. */
                  | (dpl << 13)                /* Descriptor privilege. */
                  | (1 << 15)                  /* Present. */
                  | (limit & 0xf0000)          /* Limit 16:19. */
                  | (1 << 22)                  /* 32-bit segment. */
-                 | ( granularity << 23) /* Byte/page granularity. */
+                 | (granularity << 23)        /* Byte/page granularity. */
                  | (base & 0xff000000));      /* Base 31:24. */
   return e0 | ((uint64_t) e1 << 32);
 }
@@ -120,9 +121,10 @@ make_data_desc (int dpl)
 }
 
 static uint64_t
-make_tss_desc (uint32_t base)
+make_tss_desc (void *vaddr)
 {
-  return make_seg_desc (base, 0x67, SYS_SYSTEM, TYPE_TSS_32_A, 0, GRAN_BYTE);
+  return make_seg_desc ((uint32_t) vaddr,
+                        0x67, SYS_SYSTEM, TYPE_TSS_32_A, 0, GRAN_BYTE);
 }
 
 uint64_t gdt[SEL_CNT];
@@ -150,13 +152,38 @@ gdt_init (void)
   gdt[SEL_KDSEG / sizeof *gdt] = make_data_desc (0);
   gdt[SEL_UCSEG / sizeof *gdt] = make_code_desc (3);
   gdt[SEL_UDSEG / sizeof *gdt] = make_data_desc (3);
-  gdt[SEL_TSS / sizeof *gdt] = make_tss_desc (vtop (tss));
+  gdt[SEL_TSS / sizeof *gdt] = make_tss_desc (tss);
 
   /* Load GDTR, TR. */
   gdtr_operand = make_dtr_operand (sizeof gdt - 1, gdt);
   asm volatile ("lgdt %0" :: "m" (gdtr_operand));
   asm volatile ("ltr %w0" :: "r" (SEL_TSS));
 }
+
+static void
+ram_init (void) 
+{
+  /* Start and end of kernel image,
+     and start and end of BSS segment.
+     These are created by kernel.lds. */
+  extern char _start, _end;
+  extern char _start_bss, _end_bss;
+
+  /* The "BSS" is a segment that should be initialized to zeros.
+     It isn't actually stored on disk or zeroed by the kernel
+     loader, so we have to zero it ourselves. */
+  memset (&_start_bss, 0, &_end_bss - &_start_bss);
+
+  /* Calculate how much RAM the kernel uses, and find out from
+     the bootloader how much RAM this machine has. */
+  kernel_pages = (&_end - &_start + 4095) / 4096;
+  ram_pages = *(uint32_t *) (LOADER_BASE + LOADER_RAM_PAGES);
+}
+
+void
+argv_init (void) 
+{
+}
 \f
 void
 power_off (void)