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|
/*
* linux/arch/i386/entry.S
*
* Copyright (C) 1991, 1992 Linus Torvalds
*/
/*
* entry.S contains the system-call and fault low-level handling routines.
* This also contains the timer-interrupt handler, as well as all interrupts
* and faults that can result in a task-switch.
*
* NOTE: This code handles signal-recognition, which happens every time
* after a timer-interrupt and after each system call.
*
* I changed all the .align's to 4 (16 byte alignment), as that's faster
* on a 486.
*
* Stack layout in 'ret_from_system_call':
* ptrace needs to have all regs on the stack.
* if the order here is changed, it needs to be
* updated in fork.c:copy_process, signal.c:do_signal,
* ptrace.c and ptrace.h
*
* 0(%esp) - %ebx
* 4(%esp) - %ecx
* 8(%esp) - %edx
* C(%esp) - %esi
* 10(%esp) - %edi
* 14(%esp) - %ebp
* 18(%esp) - %eax
* 1C(%esp) - %ds
* 20(%esp) - %es
* 24(%esp) - orig_eax
* 28(%esp) - %eip
* 2C(%esp) - %cs
* 30(%esp) - %eflags
* 34(%esp) - %oldesp
* 38(%esp) - %oldss
*
* "current" is in register %ebx during any slow entries.
*/
#include <linux/sys.h>
#include <linux/linkage.h>
#include <asm/segment.h>
#define ASSEMBLY
#include <asm/smp.h>
EBX = 0x00
ECX = 0x04
EDX = 0x08
ESI = 0x0C
EDI = 0x10
EBP = 0x14
EAX = 0x18
DS = 0x1C
ES = 0x20
ORIG_EAX = 0x24
EIP = 0x28
CS = 0x2C
EFLAGS = 0x30
OLDESP = 0x34
OLDSS = 0x38
CF_MASK = 0x00000001
IF_MASK = 0x00000200
NT_MASK = 0x00004000
VM_MASK = 0x00020000
/*
* these are offsets into the task-struct.
*/
state = 0
counter = 4
priority = 8
signal = 12
blocked = 16
flags = 20
dbgreg6 = 52
dbgreg7 = 56
exec_domain = 60
ENOSYS = 38
#define SAVE_ALL \
cld; \
push %es; \
push %ds; \
pushl %eax; \
pushl %ebp; \
pushl %edi; \
pushl %esi; \
pushl %edx; \
pushl %ecx; \
pushl %ebx; \
movl $(KERNEL_DS),%edx; \
mov %dx,%ds; \
mov %dx,%es;
#define RESTORE_ALL \
popl %ebx; \
popl %ecx; \
popl %edx; \
popl %esi; \
popl %edi; \
popl %ebp; \
popl %eax; \
pop %ds; \
pop %es; \
addl $4,%esp; \
iret
#define GET_CURRENT(reg) \
movl %esp, reg; \
andl $-8192, reg;
ENTRY(lcall7)
pushfl # We get a different stack layout with call gates,
pushl %eax # which has to be cleaned up later..
SAVE_ALL
movl EIP(%esp),%eax # due to call gates, this is eflags, not eip..
movl CS(%esp),%edx # this is eip..
movl EFLAGS(%esp),%ecx # and this is cs..
movl %eax,EFLAGS(%esp) #
movl %edx,EIP(%esp) # Now we move them to their "normal" places
movl %ecx,CS(%esp) #
movl %esp,%ebx
pushl %ebx
andl $-8192,%ebx # GET_CURRENT
movl exec_domain(%ebx),%edx # Get the execution domain
movl 4(%edx),%edx # Get the lcall7 handler for the domain
call *%edx
popl %eax
jmp ret_from_sys_call
#ifdef __SMP__
ALIGN
.globl ret_from_smpfork
ret_from_smpfork:
GET_CURRENT(%ebx)
btrl $0, SYMBOL_NAME(scheduler_lock)
jmp ret_from_sys_call
#endif /* __SMP__ */
/*
* Return to user mode is not as complex as all this looks,
* but we want the default path for a system call return to
* go as quickly as possible which is why some of this is
* less clear than it otherwise should be.
*/
ENTRY(system_call)
pushl %eax # save orig_eax
SAVE_ALL
GET_CURRENT(%ebx)
cmpl $(NR_syscalls),%eax
jae badsys
testb $0x20,flags(%ebx) # PF_TRACESYS
jne tracesys
call SYMBOL_NAME(sys_call_table)(,%eax,4)
movl %eax,EAX(%esp) # save the return value
ALIGN
.globl ret_from_sys_call
.globl ret_from_intr
ret_from_sys_call:
movl SYMBOL_NAME(bh_mask),%eax
andl SYMBOL_NAME(bh_active),%eax
jne handle_bottom_half
ret_with_reschedule:
cmpl $0,SYMBOL_NAME(need_resched)
jne reschedule
movl blocked(%ebx),%eax
movl %eax,%esi # save blocked in %esi for signal handling
notl %eax
andl signal(%ebx),%eax
jne signal_return
RESTORE_ALL
ALIGN
signal_return:
testl $(VM_MASK),EFLAGS(%esp)
pushl %esp
jne v86_signal_return
pushl %esi
call SYMBOL_NAME(do_signal)
addl $8,%esp
RESTORE_ALL
ALIGN
v86_signal_return:
call SYMBOL_NAME(save_v86_state)
movl %eax,%esp
pushl %eax
pushl %esi
call SYMBOL_NAME(do_signal)
addl $8,%esp
RESTORE_ALL
ALIGN
tracesys:
movl $-ENOSYS,EAX(%esp)
call SYMBOL_NAME(syscall_trace)
movl ORIG_EAX(%esp),%eax
call SYMBOL_NAME(sys_call_table)(,%eax,4)
movl %eax,EAX(%esp) # save the return value
call SYMBOL_NAME(syscall_trace)
jmp ret_from_sys_call
badsys:
movl $-ENOSYS,EAX(%esp)
jmp ret_from_sys_call
ALIGN
ret_from_exception:
movl SYMBOL_NAME(bh_mask),%eax
andl SYMBOL_NAME(bh_active),%eax
jne handle_bottom_half
ALIGN
ret_from_intr:
GET_CURRENT(%ebx)
movl EFLAGS(%esp),%eax # mix EFLAGS and CS
movb CS(%esp),%al
testl $(VM_MASK | 3),%eax # return to VM86 mode or non-supervisor?
jne ret_with_reschedule
RESTORE_ALL
ALIGN
handle_bottom_half:
pushl $ret_from_intr
jmp SYMBOL_NAME(do_bottom_half)
ALIGN
reschedule:
pushl $ret_from_sys_call
jmp SYMBOL_NAME(schedule) # test
ENTRY(divide_error)
pushl $0 # no error code
pushl $ SYMBOL_NAME(do_divide_error)
ALIGN
error_code:
push %ds
pushl %eax
xorl %eax,%eax
pushl %ebp
pushl %edi
pushl %esi
pushl %edx
decl %eax # eax = -1
pushl %ecx
pushl %ebx
xorl %ecx,%ecx # zero ecx
cld
mov %es,%cx # get the lower order bits of es
xchgl %eax, ORIG_EAX(%esp) # orig_eax (get the error code. )
movl %esp,%edx
xchgl %ecx, ES(%esp) # get the address and save es.
pushl %eax # push the error code
pushl %edx
movl $(KERNEL_DS),%edx
mov %dx,%ds
mov %dx,%es
GET_CURRENT(%ebx)
call *%ecx
addl $8,%esp
jmp ret_from_exception
ENTRY(coprocessor_error)
pushl $0
pushl $ SYMBOL_NAME(do_coprocessor_error)
jmp error_code
ENTRY(device_not_available)
pushl $-1 # mark this as an int
SAVE_ALL
GET_CURRENT(%ebx)
pushl $ret_from_exception
movl %cr0,%eax
testl $0x4,%eax # EM (math emulation bit)
je SYMBOL_NAME(math_state_restore)
pushl $0 # temporary storage for ORIG_EIP
call SYMBOL_NAME(math_emulate)
addl $4,%esp
ret
ENTRY(debug)
pushl $0
pushl $ SYMBOL_NAME(do_debug)
jmp error_code
ENTRY(nmi)
pushl $0
pushl $ SYMBOL_NAME(do_nmi)
jmp error_code
ENTRY(int3)
pushl $0
pushl $ SYMBOL_NAME(do_int3)
jmp error_code
ENTRY(overflow)
pushl $0
pushl $ SYMBOL_NAME(do_overflow)
jmp error_code
ENTRY(bounds)
pushl $0
pushl $ SYMBOL_NAME(do_bounds)
jmp error_code
ENTRY(invalid_op)
pushl $0
pushl $ SYMBOL_NAME(do_invalid_op)
jmp error_code
ENTRY(coprocessor_segment_overrun)
pushl $0
pushl $ SYMBOL_NAME(do_coprocessor_segment_overrun)
jmp error_code
ENTRY(reserved)
pushl $0
pushl $ SYMBOL_NAME(do_reserved)
jmp error_code
ENTRY(double_fault)
pushl $ SYMBOL_NAME(do_double_fault)
jmp error_code
ENTRY(invalid_TSS)
pushl $ SYMBOL_NAME(do_invalid_TSS)
jmp error_code
ENTRY(segment_not_present)
pushl $ SYMBOL_NAME(do_segment_not_present)
jmp error_code
ENTRY(stack_segment)
pushl $ SYMBOL_NAME(do_stack_segment)
jmp error_code
ENTRY(general_protection)
pushl $ SYMBOL_NAME(do_general_protection)
jmp error_code
ENTRY(alignment_check)
pushl $ SYMBOL_NAME(do_alignment_check)
jmp error_code
ENTRY(page_fault)
pushl $ SYMBOL_NAME(do_page_fault)
jmp error_code
ENTRY(spurious_interrupt_bug)
pushl $0
pushl $ SYMBOL_NAME(do_spurious_interrupt_bug)
jmp error_code
.data
ENTRY(sys_call_table)
.long SYMBOL_NAME(sys_setup) /* 0 */
.long SYMBOL_NAME(sys_exit)
.long SYMBOL_NAME(sys_fork)
.long SYMBOL_NAME(sys_read)
.long SYMBOL_NAME(sys_write)
.long SYMBOL_NAME(sys_open) /* 5 */
.long SYMBOL_NAME(sys_close)
.long SYMBOL_NAME(sys_waitpid)
.long SYMBOL_NAME(sys_creat)
.long SYMBOL_NAME(sys_link)
.long SYMBOL_NAME(sys_unlink) /* 10 */
.long SYMBOL_NAME(sys_execve)
.long SYMBOL_NAME(sys_chdir)
.long SYMBOL_NAME(sys_time)
.long SYMBOL_NAME(sys_mknod)
.long SYMBOL_NAME(sys_chmod) /* 15 */
.long SYMBOL_NAME(sys_chown)
.long SYMBOL_NAME(sys_break)
.long SYMBOL_NAME(sys_stat)
.long SYMBOL_NAME(sys_lseek)
.long SYMBOL_NAME(sys_getpid) /* 20 */
.long SYMBOL_NAME(sys_mount)
.long SYMBOL_NAME(sys_umount)
.long SYMBOL_NAME(sys_setuid)
.long SYMBOL_NAME(sys_getuid)
.long SYMBOL_NAME(sys_stime) /* 25 */
.long SYMBOL_NAME(sys_ptrace)
.long SYMBOL_NAME(sys_alarm)
.long SYMBOL_NAME(sys_fstat)
.long SYMBOL_NAME(sys_pause)
.long SYMBOL_NAME(sys_utime) /* 30 */
.long SYMBOL_NAME(sys_stty)
.long SYMBOL_NAME(sys_gtty)
.long SYMBOL_NAME(sys_access)
.long SYMBOL_NAME(sys_nice)
.long SYMBOL_NAME(sys_ftime) /* 35 */
.long SYMBOL_NAME(sys_sync)
.long SYMBOL_NAME(sys_kill)
.long SYMBOL_NAME(sys_rename)
.long SYMBOL_NAME(sys_mkdir)
.long SYMBOL_NAME(sys_rmdir) /* 40 */
.long SYMBOL_NAME(sys_dup)
.long SYMBOL_NAME(sys_pipe)
.long SYMBOL_NAME(sys_times)
.long SYMBOL_NAME(sys_prof)
.long SYMBOL_NAME(sys_brk) /* 45 */
.long SYMBOL_NAME(sys_setgid)
.long SYMBOL_NAME(sys_getgid)
.long SYMBOL_NAME(sys_signal)
.long SYMBOL_NAME(sys_geteuid)
.long SYMBOL_NAME(sys_getegid) /* 50 */
.long SYMBOL_NAME(sys_acct)
.long SYMBOL_NAME(sys_phys)
.long SYMBOL_NAME(sys_lock)
.long SYMBOL_NAME(sys_ioctl)
.long SYMBOL_NAME(sys_fcntl) /* 55 */
.long SYMBOL_NAME(sys_mpx)
.long SYMBOL_NAME(sys_setpgid)
.long SYMBOL_NAME(sys_ulimit)
.long SYMBOL_NAME(sys_olduname)
.long SYMBOL_NAME(sys_umask) /* 60 */
.long SYMBOL_NAME(sys_chroot)
.long SYMBOL_NAME(sys_ustat)
.long SYMBOL_NAME(sys_dup2)
.long SYMBOL_NAME(sys_getppid)
.long SYMBOL_NAME(sys_getpgrp) /* 65 */
.long SYMBOL_NAME(sys_setsid)
.long SYMBOL_NAME(sys_sigaction)
.long SYMBOL_NAME(sys_sgetmask)
.long SYMBOL_NAME(sys_ssetmask)
.long SYMBOL_NAME(sys_setreuid) /* 70 */
.long SYMBOL_NAME(sys_setregid)
.long SYMBOL_NAME(sys_sigsuspend)
.long SYMBOL_NAME(sys_sigpending)
.long SYMBOL_NAME(sys_sethostname)
.long SYMBOL_NAME(sys_setrlimit) /* 75 */
.long SYMBOL_NAME(sys_getrlimit)
.long SYMBOL_NAME(sys_getrusage)
.long SYMBOL_NAME(sys_gettimeofday)
.long SYMBOL_NAME(sys_settimeofday)
.long SYMBOL_NAME(sys_getgroups) /* 80 */
.long SYMBOL_NAME(sys_setgroups)
.long SYMBOL_NAME(old_select)
.long SYMBOL_NAME(sys_symlink)
.long SYMBOL_NAME(sys_lstat)
.long SYMBOL_NAME(sys_readlink) /* 85 */
.long SYMBOL_NAME(sys_uselib)
.long SYMBOL_NAME(sys_swapon)
.long SYMBOL_NAME(sys_reboot)
.long SYMBOL_NAME(old_readdir)
.long SYMBOL_NAME(old_mmap) /* 90 */
.long SYMBOL_NAME(sys_munmap)
.long SYMBOL_NAME(sys_truncate)
.long SYMBOL_NAME(sys_ftruncate)
.long SYMBOL_NAME(sys_fchmod)
.long SYMBOL_NAME(sys_fchown) /* 95 */
.long SYMBOL_NAME(sys_getpriority)
.long SYMBOL_NAME(sys_setpriority)
.long SYMBOL_NAME(sys_profil)
.long SYMBOL_NAME(sys_statfs)
.long SYMBOL_NAME(sys_fstatfs) /* 100 */
.long SYMBOL_NAME(sys_ioperm)
.long SYMBOL_NAME(sys_socketcall)
.long SYMBOL_NAME(sys_syslog)
.long SYMBOL_NAME(sys_setitimer)
.long SYMBOL_NAME(sys_getitimer) /* 105 */
.long SYMBOL_NAME(sys_newstat)
.long SYMBOL_NAME(sys_newlstat)
.long SYMBOL_NAME(sys_newfstat)
.long SYMBOL_NAME(sys_uname)
.long SYMBOL_NAME(sys_iopl) /* 110 */
.long SYMBOL_NAME(sys_vhangup)
.long SYMBOL_NAME(sys_idle)
.long SYMBOL_NAME(sys_vm86old)
.long SYMBOL_NAME(sys_wait4)
.long SYMBOL_NAME(sys_swapoff) /* 115 */
.long SYMBOL_NAME(sys_sysinfo)
.long SYMBOL_NAME(sys_ipc)
.long SYMBOL_NAME(sys_fsync)
.long SYMBOL_NAME(sys_sigreturn)
.long SYMBOL_NAME(sys_clone) /* 120 */
.long SYMBOL_NAME(sys_setdomainname)
.long SYMBOL_NAME(sys_newuname)
.long SYMBOL_NAME(sys_modify_ldt)
.long SYMBOL_NAME(sys_adjtimex)
.long SYMBOL_NAME(sys_mprotect) /* 125 */
.long SYMBOL_NAME(sys_sigprocmask)
.long SYMBOL_NAME(sys_create_module)
.long SYMBOL_NAME(sys_init_module)
.long SYMBOL_NAME(sys_delete_module)
.long SYMBOL_NAME(sys_get_kernel_syms) /* 130 */
.long SYMBOL_NAME(sys_quotactl)
.long SYMBOL_NAME(sys_getpgid)
.long SYMBOL_NAME(sys_fchdir)
.long SYMBOL_NAME(sys_bdflush)
.long SYMBOL_NAME(sys_sysfs) /* 135 */
.long SYMBOL_NAME(sys_personality)
.long SYMBOL_NAME(sys_ni_syscall) /* for afs_syscall */
.long SYMBOL_NAME(sys_setfsuid)
.long SYMBOL_NAME(sys_setfsgid)
.long SYMBOL_NAME(sys_llseek) /* 140 */
.long SYMBOL_NAME(sys_getdents)
.long SYMBOL_NAME(sys_select)
.long SYMBOL_NAME(sys_flock)
.long SYMBOL_NAME(sys_msync)
.long SYMBOL_NAME(sys_readv) /* 145 */
.long SYMBOL_NAME(sys_writev)
.long SYMBOL_NAME(sys_getsid)
.long SYMBOL_NAME(sys_fdatasync)
.long SYMBOL_NAME(sys_sysctl)
.long SYMBOL_NAME(sys_mlock) /* 150 */
.long SYMBOL_NAME(sys_munlock)
.long SYMBOL_NAME(sys_mlockall)
.long SYMBOL_NAME(sys_munlockall)
.long SYMBOL_NAME(sys_sched_setparam)
.long SYMBOL_NAME(sys_sched_getparam) /* 155 */
.long SYMBOL_NAME(sys_sched_setscheduler)
.long SYMBOL_NAME(sys_sched_getscheduler)
.long SYMBOL_NAME(sys_sched_yield)
.long SYMBOL_NAME(sys_sched_get_priority_max)
.long SYMBOL_NAME(sys_sched_get_priority_min) /* 160 */
.long SYMBOL_NAME(sys_sched_rr_get_interval)
.long SYMBOL_NAME(sys_nanosleep)
.long SYMBOL_NAME(sys_mremap)
.long SYMBOL_NAME(sys_setresuid)
.long SYMBOL_NAME(sys_getresuid) /* 165 */
.long SYMBOL_NAME(sys_vm86)
.long SYMBOL_NAME(sys_query_module)
.long SYMBOL_NAME(sys_poll)
.long SYMBOL_NAME(sys_nfsservctl)
.rept NR_syscalls-169
.long SYMBOL_NAME(sys_ni_syscall)
.endr
|
