regression: elf loading

[lunaix-os.git] / lunaix-os / kernel / asm / x86 / interrupt.S

diff --git a/lunaix-os/kernel/asm/x86/interrupt.S b/lunaix-os/kernel/asm/x86/interrupt.S
index 62c9ec512630270ec3215451ea7e33eca587244d..2961f3b7d89f50a8f01677abbf1d452bc972b323 100644 (file)
--- a/lunaix-os/kernel/asm/x86/interrupt.S
+++ b/lunaix-os/kernel/asm/x86/interrupt.S
@@ -4,17 +4,6 @@
 #include <lunaix/syscall.h>
 #define __ASM_INTR_DIAGNOSIS
 
-.macro isr_template vector, no_error_code=1
-    .global _asm_isr\vector
-    .type _asm_isr\vector, @function
-    _asm_isr\vector:
-        .if \no_error_code
-            pushl $0x0
-        .endif
-        pushl $\vector
-        jmp interrupt_wrapper
-.endm
-
 #ifdef __ASM_INTR_DIAGNOSIS
 .section .bss
     .global debug_resv
@@ -22,21 +11,14 @@
         .skip 16
 #endif
 
-.section .text
-    isr_template FAULT_DIVISION_ERROR
-    isr_template FAULT_GENERAL_PROTECTION, no_error_code=0
-    isr_template FAULT_PAGE_FAULT, no_error_code=0
-
-    isr_template LUNAIX_SYS_PANIC
-    isr_template LUNAIX_SYS_CALL
-
-    isr_template APIC_ERROR_IV
-    isr_template APIC_LINT0_IV
-    isr_template APIC_TIMER_IV
-    isr_template APIC_SPIV_IV
-    isr_template RTC_TIMER_IV
-    isr_template PC_KBD_IV
+.section .bss
+    .align 16
+    lo_tmp_stack:
+        .skip 128
+    tmp_stack:
 
+.section .text
+    .global interrupt_wrapper
     interrupt_wrapper:
         /*
          Stack layout (layout of struct isr_param)
@@ -92,7 +74,12 @@
 
         # 保存用户栈顶指针。这是因为我们允许系统调用内进行上下文切换，而这样一来，我们就失去了用户栈的信息，
         # 这样一来，就无法设置信号上下文。这主要是为了实现了pause()而做的准备
-        movl (__current), %eax  
+        movl (__current), %eax
+
+        # 保存x87FPU的状态
+        movl 92(%eax), %ebx
+        fxsave (%ebx)
+
         movl 68(%esp), %ebx     # 取出esp
         movl %ebx, 84(%eax)     # 存入__current->ustack_top
 
@@ -104,11 +91,24 @@
 
         call intr_handler
 
+        movl (%esp), %eax
+
     .global soft_iret
     soft_iret:
-        cli
-        popl %esp
+        movl %eax, %esp
 
+#ifdef __ASM_INTR_DIAGNOSIS
+        movl %eax, (debug_resv + 8)
+        movl 56(%esp), %eax
+        movl %eax, (debug_resv + 4)
+#endif
+        movl (__current), %eax
+        movl 92(%eax), %eax
+        
+        test %eax, %eax     # do we have stored x87 context?
+        jz 1f 
+        fxrstor (%eax)      
+1:
         popl %eax
         popl %ebx
         popl %ecx
@@ -126,23 +126,62 @@
 
         addl $8, %esp
 
-#ifdef __ASM_INTR_DIAGNOSIS
         pushl %eax
+#ifdef __ASM_INTR_DIAGNOSIS
         movl 4(%esp), %eax
         movl %eax, debug_resv
-        popl %eax
 #endif
+        # 处理TSS.ESP的一些边界条件。如果是正常iret（即从内核模式*优雅地*退出）
+        # 那么TSS.ESP0应该为iret进行弹栈后，%esp的值。
+        # 所以这里的边界条件是：如返回用户模式，iret会额外弹出8个字节（ss,esp）
+        movl 8(%esp), %eax
+        andl $3, %eax
+        setnz %al
+        shll $3, %eax
+        addl $16, %eax
+        addl %esp, %eax
+        movl %eax, (_tss + 4)
+        popl %eax
         iret
 
+    .global switch_to
+    switch_to:
+        # 约定
+        # arg1: 目标进程PCB地址 (next
+
+        popl %ebx               # next
+        movl __current, %eax    
+        movl 88(%eax), %ecx     # __current->pagetable
+        movl 88(%ebx), %eax     # next->pagetable
+        
+        cmpl %ecx, %eax         # if(next->pagtable != __current->pagetable) {
+        jz 1f
+        movl %eax, %cr3         #   cpu_lcr3(next->pagetable)
+                                # }
+    1:
+        movl %ebx, __current    # __current = next
+
+        # 我们已经处在了新的地址空间，为了避免影响其先前的栈布局
+        # 需要使用一个临时的栈空间
+        movl $tmp_stack, %esp
+        call signal_dispatch    # kernel/signal.c
+
+        test %eax, %eax         # do we have signal to handle?
+        jz 1f
+        jmp handle_signal
+    1:
+        leal 8(%ebx), %eax
+        jmp soft_iret
+
+    .global handle_signal
     handle_signal:
         # 注意1：任何对proc_sig的布局改动，都须及时的保证这里的一致性！
         # 注意2：handle_signal在调用之前，须确保proc_sig已经写入用户栈！
-        popl %eax               # arg1: addr of proc_sig structure in user stack
-        leal 8(%eax), %ebx
+        leal 8(%eax), %ebx      # arg1 in %eax: addr of proc_sig structure in user stack
 
-        pushl 72(%ebx)          # proc_sig->prev_context.ss
+        pushl $UDATA_SEG        # proc_sig->prev_context.proc_regs.ss
         pushl %eax              # esp
-        pushl 64(%ebx)          # proc_sig->prev_context.eflags
+        pushl 64(%ebx)          # proc_sig->prev_context.proc_regs.eflags
         pushl $UCODE_SEG        # cs
         pushl $sig_wrapper      # eip for sig wrapper
 
@@ -154,6 +193,7 @@
 
         iret  
 
+.section .usrtext
     sig_wrapper:                # in user mode
         movl %esp, %eax
         and $0xfffffff0, %esp