sync with c; .text is implied

e97519a6 · rsc · ba6cd8a6 · e97519a6 · e97519a6 · e97519a6
--- a/bootasm.S
+++ b/bootasm.S
@@ -5,15 +5,16 @@
 # memory at physical address 0x7c00 and starts executing in real mode
 # with %cs=0 %ip=7c00.

-.set CSEG32, 0x8         # kernel code segment selector
-.set DSEG32, 0x10        # kernel data segment selector
-.set CR0_PE, 0x1         # protected mode enable flag
+#define SEG_KCODE 1  // kernel code
+#define SEG_KDATA 2  // kernel data+stack
+#define SEG_KCPU  3  // kernel per-cpu data
+
+#define CR0_PE    1  // protected mode enable bit

 .code16                       # Assemble for 16-bit mode
 .globl start
 start:
  cli                         # Disable interrupts
-  cld                         # String operations increment

  # Set up the important data segment registers (DS, ES, SS).
  xorw    %ax,%ax             # Segment number zero
@@ -53,18 +54,19 @@ seta20.2:
  
  # Jump to next instruction, but in 32-bit code segment.
  # Switches processor into 32-bit mode.
-  ljmp    $CSEG32, $start32
+  ljmp    $(SEG_KCODE<<3), $start32

 .code32                       # Assemble for 32-bit mode
 start32:
  # Set up the protected-mode data segment registers
-  movw    $DSEG32, %ax            # Our data segment selector
+  movw    $(SEG_KDATA<<3), %ax    # Our data segment selector
  movw    %ax, %ds                # -> DS: Data Segment
  movw    %ax, %es                # -> ES: Extra Segment
+  movw    %ax, %ss                # -> SS: Stack Segment
+  movw    $(SEG_KCPU<<3), %ax     # Our per-cpu segment selector
  movw    %ax, %fs                # -> FS
  movw    %ax, %gs                # -> GS
-  movw    %ax, %ss                # -> SS: Stack Segment
-  
+
  # Set up the stack pointer and call into C.
  movl    $start, %esp
  call    bootmain
@@ -85,7 +87,8 @@ gdt:
  SEG_NULLASM                             # null seg
  SEG_ASM(STA_X|STA_R, 0x0, 0xffffffff)   # code seg
  SEG_ASM(STA_W, 0x0, 0xffffffff)         # data seg
+  SEG_ASM(STA_W, 0x100, 0xffffffff)       # per-cpu data seg; 0x100 is okay for now

 gdtdesc:
-  .word   0x17                            # sizeof(gdt) - 1
+  .word   0x1f                            # sizeof(gdt) - 1
  .long   gdt                             # address gdt
--- a/trapasm.S
+++ b/trapasm.S
-.text
-
-.set SEG_KDATA_SEL, 0x10   # selector for SEG_KDATA
+#define SEG_KCODE 1  // kernel code
+#define SEG_KDATA 2  // kernel data+stack
+#define SEG_KCPU  3  // kernel per-cpu data

  # vectors.S sends all traps here.
 .globl alltraps
@@ -12,10 +12,16 @@ alltraps:
  pushl %gs
  pushal
  
-  # Set up data segments.
-  movl $SEG_KDATA_SEL, %eax
-  movw %ax,%ds
-  movw %ax,%es
+  # Set up data and per-cpu segments.
+  # Can find out KDATA from %ss.
+  # Assume that KCPU is KDATA+1.
+  movw $(SEG_KDATA<<3), %ax
+  movw %ss, %ax
+  movw %ax, %ds
+  movw %ax, %es
+  movw $(SEG_KCPU<<3), %ax
+  movw %ax, %fs
+  movw %ax, %gs

  # Call trap(tf), where tf=%esp
  pushl %esp

--- a/vectors.pl
+++ b/vectors.pl
@@ -7,7 +7,6 @@

 print "# generated by vectors.pl - do not edit\n";
 print "# handlers\n";
-print ".text\n";
 print ".globl alltraps\n";
 for(my $i = 0; $i < 256; $i++){
    print ".globl vector$i\n";
@@ -29,7 +28,6 @@ for(my $i = 0; $i < 256; $i++){

 # sample output:
 #   # handlers
-#   .text
 #   .globl alltraps
 #   .globl vector0
 #   vector0: