X-Git-Url: https://scm.lunaixsky.com/lunaix-os.git/blobdiff_plain/9461d582084ab8c0d85e8dca1df276945366a84b..87067c7f16425837971f5c1b5fd0fc5338757377:/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 b4ce936..602f793 100644 --- a/lunaix-os/kernel/asm/x86/interrupt.S +++ b/lunaix-os/kernel/asm/x86/interrupt.S @@ -1,79 +1,68 @@ #define __ASM__ #include -#include +#include #include #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 debug_resv: .skip 16 + tmp_store: + .skip 4 #endif .section .bss .align 16 lo_tmp_stack: - .skip 128 + .skip 256 tmp_stack: -.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 FAULT_STACK_SEG_FAULT, no_error_code=0 - - isr_template LUNAIX_SYS_PANIC - isr_template LUNAIX_SYS_CALL - isr_template LUNAIX_SCHED - - 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 - isr_template AHCI_HBA_IV +/* + This perhaps the ugliest part in the project. + It contains code to handle arbitrary depth of + nested interrupt and all those corner cases and + nasty gotchas. + + Be aware the twists, offsets and hidden dependencies! +*/ + +.section .text + .global interrupt_wrapper interrupt_wrapper: /* Stack layout (layout of struct isr_param) - msa: [ss] - [esp] - eflags > offset = 48 + 16 = 64 - cs - eip - err_code - vector > offset = 28 + 16 + 4 = 48 + msa: [ss] > 76 + [esp] > 72 + eflags > 68 + cs > 64 + eip > 60 + err_code > 56 + vector > offset = 52 + [saved_prev_ctx] > offset = 0 + --- esp gs fs es - ds > offset = 7 * 4 = 28 + ds > offset = 7 * 4 = 28 + 4 esi ebp edi edx ecx ebx - lsa: eax > offset = 0 + eax + lsa: depth > offset = 0 las: Least Significant Address msa: Most Significant Address */ cld + + subl $52, %esp pushl %esp subl $16, %esp @@ -90,7 +79,12 @@ pushl %ebx pushl %eax - movl 60(%esp), %eax /* 取出 %cs */ + movl __current, %eax + movl 8(%eax), %eax + incl %eax + pushl %eax # nested intr: current depth + + movl 116(%esp), %eax /* 取出 %cs */ andl $0x3, %eax /* 判断 RPL */ jz 1f @@ -100,11 +94,16 @@ 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 - movl 68(%esp), %ebx # 取出esp - movl %ebx, 84(%eax) # 存入__current->ustack_top + 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 + fxsave (%ebx) + + # 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 124(%esp), %ebx # 取出esp + movl %ebx, 60(%eax) # 存入__current->ustack_top 1: movl %esp, %eax @@ -122,10 +121,18 @@ #ifdef __ASM_INTR_DIAGNOSIS movl %eax, (debug_resv + 8) - movl 56(%esp), %eax - movl %eax, (debug_resv + 4) + movl 48(%esp), %eax + movl 60(%eax), %eax + movl %eax, (debug_resv + 4) # eip #endif - + movl __current, %eax + movl 68(%eax), %eax + + test %eax, %eax # do we have stored x87 context? + jz 1f + fxrstor (%eax) +1: + popl %eax # discard isr_param::depth popl %eax popl %ebx popl %ecx @@ -141,24 +148,40 @@ movl 16(%esp), %esp + 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 + addl $8, %esp - pushl %eax #ifdef __ASM_INTR_DIAGNOSIS - movl 4(%esp), %eax + movl (%esp), %eax movl %eax, debug_resv #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 + movl 4(%esp), %eax andl $3, %eax setnz %al shll $3, %eax - addl $16, %eax + addl $12, %eax addl %esp, %eax movl %eax, (_tss + 4) - popl %eax + movl tmp_store, %eax iret .global switch_to @@ -168,8 +191,8 @@ popl %ebx # next movl __current, %eax - movl 88(%eax), %ecx # __current->pagetable - movl 88(%ebx), %eax # next->pagetable + movl 64(%eax), %ecx # __current->pagetable + movl 64(%ebx), %eax # next->pagetable cmpl %ecx, %eax # if(next->pagtable != __current->pagetable) { jz 1f @@ -194,13 +217,17 @@ 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.ss + pushl $UDATA_SEG # proc_sig->prev_context.proc_regs.ss pushl %eax # esp - pushl 64(%ebx) # proc_sig->prev_context.eflags + + 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 @@ -208,21 +235,4 @@ 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