Change do_trap() to be a single table-driven function instead of
inlining it into many different fault handlers, saving about 1k of memory.
-- Brian Gerst
diff -urN linux-2.5.59-bk1/arch/i386/kernel/entry.S linux-b2/arch/i386/kernel/entry.S --- linux-2.5.59-bk1/arch/i386/kernel/entry.S 2003-02-07 14:46:13.000000000 -0500 +++ linux-b2/arch/i386/kernel/entry.S 2003-02-07 14:58:25.000000000 -0500 @@ -404,26 +404,55 @@ /* The include is where all of the SMP etc. interrupts come from */ #include "entry_arch.h" -ENTRY(divide_error) - pushl $0 # no error code - pushl $do_divide_error +#define TRAP(name,nr) \ +ENTRY(name) \ + pushl $0; \ + pushl $nr; \ + jmp error_code + +#define TRAP_CODE(name,nr) \ +ENTRY(name) \ + pushl $nr; \ + jmp error_code + +TRAP(divide_error,0) +TRAP(debug,1) +TRAP(int3,3) +TRAP(overflow,4) +TRAP(bounds,5) +TRAP(invalid_op,6) +TRAP_CODE(double_fault,8) +TRAP(coprocessor_segment_overrun,9) +TRAP_CODE(invalid_TSS,10) +TRAP_CODE(segment_not_present,11) +TRAP_CODE(stack_segment,12) +TRAP_CODE(general_protection,13) +TRAP_CODE(page_fault,14) +TRAP(spurious_interrupt_bug,15) +TRAP(coprocessor_error,16) +TRAP_CODE(alignment_check,17) +#ifdef CONFIG_X86_MCE +TRAP(machine_check,18) +#else +#define do_machine_check 0 +#endif +TRAP(simd_coprocessor_error,19) + ALIGN error_code: pushl %ds pushl %eax - xorl %eax, %eax pushl %ebp pushl %edi pushl %esi pushl %edx - decl %eax # eax = -1 pushl %ecx pushl %ebx cld movl %es, %ecx movl ORIG_EAX(%esp), %esi # get the error code - movl ES(%esp), %edi # get the function address - movl %eax, ORIG_EAX(%esp) + movl ES(%esp), %edi # get the trap number + movl %edi, ORIG_EAX(%esp) movl %ecx, ES(%esp) movl %esp, %edx pushl %esi # push the error code @@ -431,20 +460,10 @@ movl $(__USER_DS), %edx movl %edx, %ds movl %edx, %es - call *%edi + call *trap_table(,%edi,4) addl $8, %esp jmp ret_from_exception -ENTRY(coprocessor_error) - pushl $0 - pushl $do_coprocessor_error - jmp error_code - -ENTRY(simd_coprocessor_error) - pushl $0 - pushl $do_simd_coprocessor_error - jmp error_code - ENTRY(device_not_available) pushl $-1 # mark this as an int SAVE_ALL @@ -460,11 +479,6 @@ addl $4, %esp jmp ret_from_exception -ENTRY(debug) - pushl $0 - pushl $do_debug - jmp error_code - ENTRY(nmi) pushl %eax SAVE_ALL @@ -475,72 +489,29 @@ addl $8, %esp RESTORE_ALL -ENTRY(int3) - pushl $0 - pushl $do_int3 - jmp error_code - -ENTRY(overflow) - pushl $0 - pushl $do_overflow - jmp error_code - -ENTRY(bounds) - pushl $0 - pushl $do_bounds - jmp error_code - -ENTRY(invalid_op) - pushl $0 - pushl $do_invalid_op - jmp error_code - -ENTRY(coprocessor_segment_overrun) - pushl $0 - pushl $do_coprocessor_segment_overrun - jmp error_code - -ENTRY(double_fault) - pushl $do_double_fault - jmp error_code - -ENTRY(invalid_TSS) - pushl $do_invalid_TSS - jmp error_code - -ENTRY(segment_not_present) - pushl $do_segment_not_present - jmp error_code - -ENTRY(stack_segment) - pushl $do_stack_segment - jmp error_code - -ENTRY(general_protection) - pushl $do_general_protection - jmp error_code - -ENTRY(alignment_check) - pushl $do_alignment_check - jmp error_code - -ENTRY(page_fault) - pushl $do_page_fault - jmp error_code - -#ifdef CONFIG_X86_MCE -ENTRY(machine_check) - pushl $0 - pushl $do_machine_check - jmp error_code -#endif - -ENTRY(spurious_interrupt_bug) - pushl $0 - pushl $do_spurious_interrupt_bug - jmp error_code - .data +ENTRY(trap_table) + .long do_trap /* divide */ + .long do_debug + .long 0 /* nmi */ + .long do_trap /* int3 */ + .long do_trap /* overflow */ + .long do_trap /* bounds */ + .long do_trap /* invalid op */ + .long 0 /* device not available */ + .long do_trap /* double fault */ + .long do_trap /* coprocessor segment */ + .long do_trap /* invalid TSS */ + .long do_trap /* segment not present */ + .long do_trap /* stack segment */ + .long do_trap /* general protection */ + .long do_page_fault + .long do_spurious_interrupt_bug + .long do_coprocessor_error + .long do_trap /* alignment check */ + .long do_machine_check + .long do_simd_coprocessor_error + ENTRY(sys_call_table) .long sys_restart_syscall /* 0 - old "setup()" system call, used for restarting */ .long sys_exit diff -urN linux-2.5.59-bk1/arch/i386/kernel/traps.c linux-b2/arch/i386/kernel/traps.c --- linux-2.5.59-bk1/arch/i386/kernel/traps.c 2003-01-13 16:20:57.000000000 -0500 +++ linux-b2/arch/i386/kernel/traps.c 2003-02-07 14:58:25.000000000 -0500 @@ -258,126 +258,82 @@ do_exit(SIGSEGV); } -static inline void die_if_kernel(const char * str, struct pt_regs * regs, long err) +static void siginfo_intdiv(siginfo_t *info) { - if (!(regs->eflags & VM_MASK) && !(3 & regs->xcs)) - die(str, regs, err); + info->si_code = FPE_INTDIV; } -static inline unsigned long get_cr2(void) +static void siginfo_illopn(siginfo_t *info) { - unsigned long address; + info->si_code = ILL_ILLOPN; +} - /* get the address */ - __asm__("movl %%cr2,%0":"=r" (address)); - return address; +static void siginfo_adraln(siginfo_t *info) +{ + info->si_code = BUS_ADRALN; + /* Is this correct? */ + __asm__("movl %%cr2,%0" : "=r" (info->si_addr)); } -static inline void do_trap(int trapnr, int signr, char *str, int vm86, - struct pt_regs * regs, long error_code, siginfo_t *info) +static struct trap_info { + int signr; + char *name; + void (*siginfo)(siginfo_t *); +} trap_info[] = { + [ 0] = { SIGFPE, "divide error", siginfo_intdiv }, + [ 3] = { SIGTRAP, "int3", NULL }, + [ 4] = { SIGSEGV, "overflow", NULL }, + [ 5] = { SIGSEGV, "bounds", NULL }, + [ 6] = { SIGILL, "invalid operand", siginfo_illopn }, + [ 8] = { SIGSEGV, "double fault", NULL }, + [ 9] = { SIGFPE, "coprocessor segment overrun", NULL }, + [10] = { SIGSEGV, "invalid TSS", NULL }, + [11] = { SIGBUS, "segment not present", NULL }, + [12] = { SIGBUS, "stack segment", NULL }, + [13] = { SIGSEGV, "general protection fault", NULL }, + [17] = { SIGBUS, "alignment check", siginfo_adraln }, + [19] = { SIGSEGV, "cache flush denied", NULL }, +}; + +asmlinkage void do_trap(struct pt_regs * regs, long error_code) { - if (regs->eflags & VM_MASK) { - if (vm86) - goto vm86_trap; - goto trap_signal; - } + int trapnr = regs->orig_eax; + struct trap_info *info = &trap_info[trapnr]; + + if (regs->eflags & VM_MASK) + goto vm86_trap; if (!(regs->xcs & 3)) goto kernel_trap; trap_signal: { struct task_struct *tsk = current; + siginfo_t siginfo; tsk->thread.error_code = error_code; tsk->thread.trap_no = trapnr; - if (info) - force_sig_info(signr, info, tsk); - else - force_sig(signr, tsk); + siginfo.si_signo = info->signr; + siginfo.si_errno = 0; + siginfo.si_code = __SI_FAULT; + siginfo.si_addr = (void *) regs->eip; + if (info->siginfo) + info->siginfo(&siginfo); + force_sig_info(info->signr, &siginfo, tsk); return; } kernel_trap: { if (!fixup_exception(regs)) - die(str, regs, error_code); + die(info->name, regs, error_code); return; } vm86_trap: { - int ret = handle_vm86_trap((struct kernel_vm86_regs *) regs, error_code, trapnr); - if (ret) goto trap_signal; + if (handle_vm86_trap((struct kernel_vm86_regs *) regs, error_code, trapnr)); + goto trap_signal; return; } } -#define DO_ERROR(trapnr, signr, str, name) \ -asmlinkage void do_##name(struct pt_regs * regs, long error_code) \ -{ \ - do_trap(trapnr, signr, str, 0, regs, error_code, NULL); \ -} - -#define DO_ERROR_INFO(trapnr, signr, str, name, sicode, siaddr) \ -asmlinkage void do_##name(struct pt_regs * regs, long error_code) \ -{ \ - siginfo_t info; \ - info.si_signo = signr; \ - info.si_errno = 0; \ - info.si_code = sicode; \ - info.si_addr = (void *)siaddr; \ - do_trap(trapnr, signr, str, 0, regs, error_code, &info); \ -} - -#define DO_VM86_ERROR(trapnr, signr, str, name) \ -asmlinkage void do_##name(struct pt_regs * regs, long error_code) \ -{ \ - do_trap(trapnr, signr, str, 1, regs, error_code, NULL); \ -} - -#define DO_VM86_ERROR_INFO(trapnr, signr, str, name, sicode, siaddr) \ -asmlinkage void do_##name(struct pt_regs * regs, long error_code) \ -{ \ - siginfo_t info; \ - info.si_signo = signr; \ - info.si_errno = 0; \ - info.si_code = sicode; \ - info.si_addr = (void *)siaddr; \ - do_trap(trapnr, signr, str, 1, regs, error_code, &info); \ -} - -DO_VM86_ERROR_INFO( 0, SIGFPE, "divide error", divide_error, FPE_INTDIV, regs->eip) -DO_VM86_ERROR( 3, SIGTRAP, "int3", int3) -DO_VM86_ERROR( 4, SIGSEGV, "overflow", overflow) -DO_VM86_ERROR( 5, SIGSEGV, "bounds", bounds) -DO_ERROR_INFO( 6, SIGILL, "invalid operand", invalid_op, ILL_ILLOPN, regs->eip) -DO_VM86_ERROR( 7, SIGSEGV, "device not available", device_not_available) -DO_ERROR( 8, SIGSEGV, "double fault", double_fault) -DO_ERROR( 9, SIGFPE, "coprocessor segment overrun", coprocessor_segment_overrun) -DO_ERROR(10, SIGSEGV, "invalid TSS", invalid_TSS) -DO_ERROR(11, SIGBUS, "segment not present", segment_not_present) -DO_ERROR(12, SIGBUS, "stack segment", stack_segment) -DO_ERROR_INFO(17, SIGBUS, "alignment check", alignment_check, BUS_ADRALN, get_cr2()) - -asmlinkage void do_general_protection(struct pt_regs * regs, long error_code) -{ - if (regs->eflags & VM_MASK) - goto gp_in_vm86; - - if (!(regs->xcs & 3)) - goto gp_in_kernel; - - current->thread.error_code = error_code; - current->thread.trap_no = 13; - force_sig(SIGSEGV, current); - return; - -gp_in_vm86: - handle_vm86_fault((struct kernel_vm86_regs *) regs, error_code); - return; - -gp_in_kernel: - if (!fixup_exception(regs)) - die("general protection fault", regs, error_code); -} - static void mem_parity_error(unsigned char reason, struct pt_regs * regs) { printk("Uhhuh. NMI received. Dazed and confused, but trying to continue\n"); @@ -703,15 +659,7 @@ * Handle strange cache flush from user space exception * in all other cases. This is undocumented behaviour. */ - if (regs->eflags & VM_MASK) { - handle_vm86_fault((struct kernel_vm86_regs *)regs, - error_code); - return; - } - die_if_kernel("cache flush denied", regs, error_code); - current->thread.trap_no = 19; - current->thread.error_code = error_code; - force_sig(SIGSEGV, current); + do_trap(regs, error_code); } } diff -urN linux-2.5.59-bk1/arch/i386/kernel/vm86.c linux-b2/arch/i386/kernel/vm86.c --- linux-2.5.59-bk1/arch/i386/kernel/vm86.c 2003-01-13 16:20:56.000000000 -0500 +++ linux-b2/arch/i386/kernel/vm86.c 2003-02-07 15:07:05.000000000 -0500 @@ -502,6 +502,22 @@ int handle_vm86_trap(struct kernel_vm86_regs * regs, long error_code, int trapno) { + switch(trapno) { + case 13: + case 19: + handle_vm86_fault(regs, error_code); + return 0; + case 0: + case 1: + case 3: + case 4: + case 5: + case 7: + break; + default: + return 1; + }; + if (VMPI.is_vm86pus) { if ( (trapno==3) || (trapno==1) ) return_to_32bit(regs, VM86_TRAP + (trapno << 8)); diff -urN linux-2.5.59-bk1/arch/i386/mm/fault.c linux-b2/arch/i386/mm/fault.c --- linux-2.5.59-bk1/arch/i386/mm/fault.c 2003-01-13 16:20:57.000000000 -0500 +++ linux-b2/arch/i386/mm/fault.c 2003-02-07 14:58:25.000000000 -0500 @@ -136,7 +136,7 @@ console_loglevel = loglevel_save; } -asmlinkage void do_invalid_op(struct pt_regs *, unsigned long); +asmlinkage void do_trap(struct pt_regs *, unsigned long); /* * This routine handles page faults. It determines the address, @@ -302,7 +302,8 @@ nr = (address - idt_descr.address) >> 3; if (nr == 6) { - do_invalid_op(regs, 0); + regs->orig_eax = 6; + do_trap(regs, 0); return; } }
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This archive was generated by hypermail 2b29 : Sat Feb 15 2003 - 22:00:19 EST