#define __ASM__
#include <arch/x86/interrupts.h>
-#include <lunaix/common.h>
+#include <arch/x86/i386_asm.h>
+#include <arch/x86/tss.h>
#include <lunaix/syscall.h>
#define __ASM_INTR_DIAGNOSIS
.section .bss
.align 16
lo_tmp_stack:
- .skip 128
+ .skip 256
tmp_stack:
/*
*/
+#define regsize 4
+
+/* stack layout: saved interrupt context */
+ .struct 0
+idepth:
+ .struct idepth + regsize
+ieax:
+ .struct ieax + regsize
+iebx:
+ .struct iebx + regsize
+iecx:
+ .struct iecx + regsize
+iedx:
+ .struct iedx + regsize
+iedi:
+ .struct iedi + regsize
+iebp:
+ .struct iebp + regsize
+iesi:
+ .struct iesi + regsize
+ids:
+ .struct ids + regsize
+ies:
+ .struct ies + regsize
+ifs:
+ .struct ifs + regsize
+igs:
+ .struct igs + regsize
+iesp:
+ .struct iesp + regsize
+isave_prev:
+ .struct isave_prev + regsize
+ivec:
+ .struct ivec + regsize
+iecode:
+ .struct iecode + regsize
+ieip:
+ .struct ieip + regsize
+ics:
+ .struct ics + regsize
+ieflags:
+ .struct ieflags + regsize
+iuesp:
+ .struct iuesp + regsize
+iuss:
+
+
+/* stack layout: execution (flow-control) state context */
+ .struct 0
+exsave_prev:
+ .struct exsave_prev + regsize
+exvec:
+ .struct exvec + regsize
+execode:
+ .struct execode + regsize
+exeip:
+ .struct exeip + regsize
+excs:
+ .struct excs + regsize
+exeflags:
+ .struct exeflags + regsize
+exuesp:
+ .struct exuesp + regsize
+exuss:
+
+/* struct layout: critical section of struct proc_info */
+ .struct 0
+proc_pid:
+ .struct proc_pid + regsize
+proc_parent:
+ .struct proc_parent + regsize
+proc_intr_ctx:
+ .struct proc_intr_ctx + regsize
+proc_ustack_top:
+ .struct proc_ustack_top + regsize
+proc_page_table:
+ .struct proc_page_table + regsize
+proc_fxstate:
+
.section .text
.global interrupt_wrapper
interrupt_wrapper:
/*
Stack layout (layout of struct isr_param)
- msa: [ss] > 76
- [esp] > 72
- eflags > 68
- cs > 64
- eip > 60
- err_code > 56
- vector > offset = 52
+ msa: [ss] > 76 -> 28
+ [esp] > 72 -> 24
+ eflags > 68 -> 20
+ cs > 64 -> 16
+ eip > 60 -> 12
+ err_code > 56 -> 8
+ vector > offset = 52 -> 4
[saved_prev_ctx] > offset = 0
---
- esp
+ esp > 12 * 4 = 48
gs
fs
es
- ds > offset = 7 * 4 = 28 + 4
+ ds > offset = 8 * 4 = 32
esi
ebp
edi
*/
cld
- subl $52, %esp
+ subl $4, %esp
pushl %esp
subl $16, %esp
pushl %eax
movl __current, %eax
- movl 8(%eax), %eax
+ movl proc_intr_ctx(%eax), %eax
incl %eax
pushl %eax # nested intr: current depth
- movl 116(%esp), %eax /* 取出 %cs */
+ movl ics(%esp), %eax /* 取出 %cs */
andl $0x3, %eax /* 判断 RPL */
jz 1f
movw %ax, %ds
movw %ax, %es
- # 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
+ # FIXME: Save x87 context to user stack, rather than kernel's memory.
# 保存x87FPU的状态
- movl 68(%eax), %ebx
+ movl proc_fxstate(%eax), %ebx
fxsave (%ebx)
- movl 124(%esp), %ebx # 取出esp
- movl %ebx, 60(%eax) # 存入__current->ustack_top
+ # 保存用户栈顶指针。因为我们允许同级中断的产生，所以需要该手段跟踪用户栈的地址。
+ movl iuesp(%esp), %ebx # 取出esp
+ movl %ebx, proc_ustack_top(%eax) # 存入__current->ustack_top
1:
movl %esp, %eax
#ifdef __ASM_INTR_DIAGNOSIS
movl %eax, (debug_resv + 8)
- movl 48(%esp), %eax
- movl 60(%eax), %eax
+ movl iesp(%esp), %eax
+ movl exeip(%eax), %eax
movl %eax, (debug_resv + 4) # eip
#endif
movl __current, %eax
- movl 68(%eax), %eax
+ movl proc_fxstate(%eax), %eax
test %eax, %eax # do we have stored x87 context?
jz 1f
- fxrstor (%eax)
+ fxrstor (%eax)
+
1:
popl %eax # discard isr_param::depth
popl %eax
movl %eax, tmp_store
movl __current, %eax
+
+
# nested intr: restore saved context
- popl 8(%eax) # depth
- popl 12(%eax) # eax
- popl 16(%eax) # ebx
- popl 20(%eax) # ecx
- popl 24(%eax) # edx
- popl 28(%eax) # edi
- popl 32(%eax) # ebp
- popl 36(%eax) # esi
- popl 40(%eax) # ds
- popl 44(%eax) # es
- popl 48(%eax) # fs
- popl 52(%eax) # gs
- popl 56(%eax) # esp
+ popl proc_intr_ctx(%eax)
addl $8, %esp
shll $3, %eax
addl $12, %eax
addl %esp, %eax
- movl %eax, (_tss + 4)
+ movl %eax, (_tss + tss_esp0_off)
movl tmp_store, %eax
+
iret
.global switch_to
popl %ebx # next
movl __current, %eax
- movl 64(%eax), %ecx # __current->pagetable
- movl 64(%ebx), %eax # next->pagetable
+ movl proc_page_table(%eax), %ecx # __current->pagetable
+ movl proc_page_table(%ebx), %eax # next->pagetable
cmpl %ecx, %eax # if(next->pagtable != __current->pagetable) {
jz 1f
# 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
+
+ # 更新 tss
+ movl proc_intr_ctx(%ebx), %eax # proc->intr_ctx
+ movl iesp(%eax), %eax # intr_ctx->esp
+ movl %eax, (tss_esp0_off + _tss)
+
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
+ movl proc_intr_ctx(%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！
- leal 8(%eax), %ebx # arg1 in %eax: addr of proc_sig structure in user stack
+ # arg1 in %eax: addr of proc_sig structure in user stack
+ leal 12(%eax), %ebx # %ebx = &proc_sig->prev_context
pushl $UDATA_SEG # proc_sig->prev_context.proc_regs.ss
pushl %eax # esp
+
movl 48(%ebx), %ebx
pushl 68(%ebx) # proc_sig->prev_context.proc_regs.execp->eflags
+
pushl $UCODE_SEG # cs
- pushl $sig_wrapper # eip for sig wrapper
+ pushl 4(%eax) # %eip = proc_sig->sigact
movw $UDATA_SEG, %cx # switch data seg to user mode
movw %cx, %es
movw %cx, %fs
movw %cx, %gs
- iret
-
-.section .usrtext
- sig_wrapper: # in user mode
- movl %esp, %eax
- and $0xfffffff0, %esp
- subl $8, %esp
- pushl %eax # Addr to proc_sig structure
- pushl 4(%eax) # proc_sig->sig_num ---- 16 bytes aligned
-
- call *(%eax) # invoke signal handler
-
- # invoke the sigreturn syscall to exit the signal wrapper
- movl $__SYSCALL_sigreturn, %eax
- movl 4(%esp), %ebx
- int $LUNAIX_SYS_CALL
-
- ud2 # never reach!
\ No newline at end of file
+ iret
\ No newline at end of file
git://scm.lunaixsky.com / lunaix-os.git / blobdiff