/* * arch/s390/kernel/entry.S * S390 low-level entry points. * * S390 version * Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com), * Hartmut Penner (hp@de.ibm.com), * Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com), */ #include #include #include #include #include #include #include #include #include #include #include /* * Stack layout for the system_call stack entry. * The first few entries are identical to the user_regs_struct. */ SP_PTREGS = STACK_FRAME_OVERHEAD SP_ARGS = STACK_FRAME_OVERHEAD + __PT_ARGS SP_PSW = STACK_FRAME_OVERHEAD + __PT_PSW SP_R0 = STACK_FRAME_OVERHEAD + __PT_GPRS SP_R1 = STACK_FRAME_OVERHEAD + __PT_GPRS + 4 SP_R2 = STACK_FRAME_OVERHEAD + __PT_GPRS + 8 SP_R3 = STACK_FRAME_OVERHEAD + __PT_GPRS + 12 SP_R4 = STACK_FRAME_OVERHEAD + __PT_GPRS + 16 SP_R5 = STACK_FRAME_OVERHEAD + __PT_GPRS + 20 SP_R6 = STACK_FRAME_OVERHEAD + __PT_GPRS + 24 SP_R7 = STACK_FRAME_OVERHEAD + __PT_GPRS + 28 SP_R8 = STACK_FRAME_OVERHEAD + __PT_GPRS + 32 SP_R9 = STACK_FRAME_OVERHEAD + __PT_GPRS + 36 SP_R10 = STACK_FRAME_OVERHEAD + __PT_GPRS + 40 SP_R11 = STACK_FRAME_OVERHEAD + __PT_GPRS + 44 SP_R12 = STACK_FRAME_OVERHEAD + __PT_GPRS + 48 SP_R13 = STACK_FRAME_OVERHEAD + __PT_GPRS + 52 SP_R14 = STACK_FRAME_OVERHEAD + __PT_GPRS + 56 SP_R15 = STACK_FRAME_OVERHEAD + __PT_GPRS + 60 SP_ORIG_R2 = STACK_FRAME_OVERHEAD + __PT_ORIG_GPR2 SP_ILC = STACK_FRAME_OVERHEAD + __PT_ILC SP_TRAP = STACK_FRAME_OVERHEAD + __PT_TRAP SP_SIZE = STACK_FRAME_OVERHEAD + __PT_SIZE _TIF_WORK_SVC = (_TIF_SIGPENDING | _TIF_NEED_RESCHED | \ _TIF_RESTART_SVC | _TIF_SINGLE_STEP ) _TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_NEED_RESCHED) STACK_SHIFT = PAGE_SHIFT + THREAD_ORDER STACK_SIZE = 1 << STACK_SHIFT #define BASED(name) name-system_call(%r13) /* * Register usage in interrupt handlers: * R9 - pointer to current task structure * R13 - pointer to literal pool * R14 - return register for function calls * R15 - kernel stack pointer */ .macro STORE_TIMER lc_offset #ifdef CONFIG_VIRT_CPU_ACCOUNTING stpt \lc_offset #endif .endm #ifdef CONFIG_VIRT_CPU_ACCOUNTING .macro UPDATE_VTIME lc_from,lc_to,lc_sum lm %r10,%r11,\lc_from sl %r10,\lc_to sl %r11,\lc_to+4 bc 3,BASED(0f) sl %r10,BASED(.Lc_1) 0: al %r10,\lc_sum al %r11,\lc_sum+4 bc 12,BASED(1f) al %r10,BASED(.Lc_1) 1: stm %r10,%r11,\lc_sum .endm #endif .macro SAVE_ALL_BASE savearea stm %r12,%r15,\savearea l %r13,__LC_SVC_NEW_PSW+4 # load &system_call to %r13 .endm .macro SAVE_ALL psworg,savearea,sync la %r12,\psworg .if \sync tm \psworg+1,0x01 # test problem state bit bz BASED(2f) # skip stack setup save l %r15,__LC_KERNEL_STACK # problem state -> load ksp .else tm \psworg+1,0x01 # test problem state bit bnz BASED(1f) # from user -> load async stack clc \psworg+4(4),BASED(.Lcritical_end) bhe BASED(0f) clc \psworg+4(4),BASED(.Lcritical_start) bl BASED(0f) l %r14,BASED(.Lcleanup_critical) basr %r14,%r14 tm 0(%r12),0x01 # retest problem state after cleanup bnz BASED(1f) 0: l %r14,__LC_ASYNC_STACK # are we already on the async stack ? slr %r14,%r15 sra %r14,STACK_SHIFT be BASED(2f) 1: l %r15,__LC_ASYNC_STACK .endif #ifdef CONFIG_CHECK_STACK b BASED(3f) 2: tml %r15,STACK_SIZE - CONFIG_STACK_GUARD bz BASED(stack_overflow) 3: #endif 2: s %r15,BASED(.Lc_spsize) # make room for registers & psw mvc SP_PSW(8,%r15),0(%r12) # move user PSW to stack la %r12,\psworg st %r2,SP_ORIG_R2(%r15) # store original content of gpr 2 icm %r12,12,__LC_SVC_ILC stm %r0,%r11,SP_R0(%r15) # store gprs %r0-%r11 to kernel stack st %r12,SP_ILC(%r15) mvc SP_R12(16,%r15),\savearea # move %r12-%r15 to stack la %r12,0 st %r12,__SF_BACKCHAIN(%r15) # clear back chain .endm .macro RESTORE_ALL sync mvc __LC_RETURN_PSW(8),SP_PSW(%r15) # move user PSW to lowcore .if !\sync ni __LC_RETURN_PSW+1,0xfd # clear wait state bit .endif lm %r0,%r15,SP_R0(%r15) # load gprs 0-15 of user STORE_TIMER __LC_EXIT_TIMER lpsw __LC_RETURN_PSW # back to caller .endm /* * Scheduler resume function, called by switch_to * gpr2 = (task_struct *) prev * gpr3 = (task_struct *) next * Returns: * gpr2 = prev */ .globl __switch_to __switch_to: basr %r1,0 __switch_to_base: tm __THREAD_per(%r3),0xe8 # new process is using per ? bz __switch_to_noper-__switch_to_base(%r1) # if not we're fine stctl %c9,%c11,__SF_EMPTY(%r15) # We are using per stuff clc __THREAD_per(12,%r3),__SF_EMPTY(%r15) be __switch_to_noper-__switch_to_base(%r1) # we got away w/o bashing TLB's lctl %c9,%c11,__THREAD_per(%r3) # Nope we didn't __switch_to_noper: stm %r6,%r15,__SF_GPRS(%r15)# store __switch_to registers of prev task st %r15,__THREAD_ksp(%r2) # store kernel stack to prev->tss.ksp l %r15,__THREAD_ksp(%r3) # load kernel stack from next->tss.ksp lm %r6,%r15,__SF_GPRS(%r15)# load __switch_to registers of next task st %r3,__LC_CURRENT # __LC_CURRENT = current task struct lctl %c4,%c4,__TASK_pid(%r3) # load pid to control reg. 4 l %r3,__THREAD_info(%r3) # load thread_info from task struct st %r3,__LC_THREAD_INFO ahi %r3,STACK_SIZE st %r3,__LC_KERNEL_STACK # __LC_KERNEL_STACK = new kernel stack br %r14 __critical_start: /* * SVC interrupt handler routine. System calls are synchronous events and * are executed with interrupts enabled. */ .globl system_call system_call: STORE_TIMER __LC_SYNC_ENTER_TIMER sysc_saveall: SAVE_ALL_BASE __LC_SAVE_AREA SAVE_ALL __LC_SVC_OLD_PSW,__LC_SAVE_AREA,1 lh %r7,0x8a # get svc number from lowcore #ifdef CONFIG_VIRT_CPU_ACCOUNTING sysc_vtime: tm SP_PSW+1(%r15),0x01 # interrupting from user ? bz BASED(sysc_do_svc) UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER sysc_stime: UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER sysc_update: mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER #endif sysc_do_svc: l %r9,__LC_THREAD_INFO # load pointer to thread_info struct sla %r7,2 # *4 and test for svc 0 bnz BASED(sysc_nr_ok) # svc number > 0 # svc 0: system call number in %r1 cl %r1,BASED(.Lnr_syscalls) bnl BASED(sysc_nr_ok) lr %r7,%r1 # copy svc number to %r7 sla %r7,2 # *4 sysc_nr_ok: mvc SP_ARGS(4,%r15),SP_R7(%r15) sysc_do_restart: tm __TI_flags+3(%r9),(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT) l %r8,sys_call_table-system_call(%r7,%r13) # get system call addr. bnz BASED(sysc_tracesys) basr %r14,%r8 # call sys_xxxx st %r2,SP_R2(%r15) # store return value (change R2 on stack) # ATTENTION: check sys_execve_glue before # changing anything here !! sysc_return: tm SP_PSW+1(%r15),0x01 # returning to user ? bno BASED(sysc_leave) tm __TI_flags+3(%r9),_TIF_WORK_SVC bnz BASED(sysc_work) # there is work to do (signals etc.) sysc_leave: RESTORE_ALL 1 # # recheck if there is more work to do # sysc_work_loop: tm __TI_flags+3(%r9),_TIF_WORK_SVC bz BASED(sysc_leave) # there is no work to do # # One of the work bits is on. Find out which one. # sysc_work: tm __TI_flags+3(%r9),_TIF_NEED_RESCHED bo BASED(sysc_reschedule) tm __TI_flags+3(%r9),_TIF_SIGPENDING bo BASED(sysc_sigpending) tm __TI_flags+3(%r9),_TIF_RESTART_SVC bo BASED(sysc_restart) tm __TI_flags+3(%r9),_TIF_SINGLE_STEP bo BASED(sysc_singlestep) b BASED(sysc_leave) # # _TIF_NEED_RESCHED is set, call schedule # sysc_reschedule: l %r1,BASED(.Lschedule) la %r14,BASED(sysc_work_loop) br %r1 # call scheduler # # _TIF_SIGPENDING is set, call do_signal # sysc_sigpending: ni __TI_flags+3(%r9),255-_TIF_SINGLE_STEP # clear TIF_SINGLE_STEP la %r2,SP_PTREGS(%r15) # load pt_regs sr %r3,%r3 # clear *oldset l %r1,BASED(.Ldo_signal) basr %r14,%r1 # call do_signal tm __TI_flags+3(%r9),_TIF_RESTART_SVC bo BASED(sysc_restart) tm __TI_flags+3(%r9),_TIF_SINGLE_STEP bo BASED(sysc_singlestep) b BASED(sysc_leave) # out of here, do NOT recheck # # _TIF_RESTART_SVC is set, set up registers and restart svc # sysc_restart: ni __TI_flags+3(%r9),255-_TIF_RESTART_SVC # clear TIF_RESTART_SVC l %r7,SP_R2(%r15) # load new svc number sla %r7,2 mvc SP_R2(4,%r15),SP_ORIG_R2(%r15) # restore first argument lm %r2,%r6,SP_R2(%r15) # load svc arguments b BASED(sysc_do_restart) # restart svc # # _TIF_SINGLE_STEP is set, call do_single_step # sysc_singlestep: ni __TI_flags+3(%r9),255-_TIF_SINGLE_STEP # clear TIF_SINGLE_STEP mvi SP_TRAP+1(%r15),0x28 # set trap indication to pgm check la %r2,SP_PTREGS(%r15) # address of register-save area l %r1,BASED(.Lhandle_per) # load adr. of per handler la %r14,BASED(sysc_return) # load adr. of system return br %r1 # branch to do_single_step __critical_end: # # call trace before and after sys_call # sysc_tracesys: l %r1,BASED(.Ltrace) la %r2,SP_PTREGS(%r15) # load pt_regs la %r3,0 srl %r7,2 st %r7,SP_R2(%r15) basr %r14,%r1 clc SP_R2(4,%r15),BASED(.Lnr_syscalls) bnl BASED(sysc_tracenogo) l %r7,SP_R2(%r15) # strace might have changed the sll %r7,2 # system call l %r8,sys_call_table-system_call(%r7,%r13) sysc_tracego: lm %r3,%r6,SP_R3(%r15) l %r2,SP_ORIG_R2(%r15) basr %r14,%r8 # call sys_xxx st %r2,SP_R2(%r15) # store return value sysc_tracenogo: tm __TI_flags+3(%r9),(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT) bz BASED(sysc_return) l %r1,BASED(.Ltrace) la %r2,SP_PTREGS(%r15) # load pt_regs la %r3,1 la %r14,BASED(sysc_return) br %r1 # # a new process exits the kernel with ret_from_fork # .globl ret_from_fork ret_from_fork: l %r13,__LC_SVC_NEW_PSW+4 l %r9,__LC_THREAD_INFO # load pointer to thread_info struct tm SP_PSW+1(%r15),0x01 # forking a kernel thread ? bo BASED(0f) st %r15,SP_R15(%r15) # store stack pointer for new kthread 0: l %r1,BASED(.Lschedtail) basr %r14,%r1 stosm __SF_EMPTY(%r15),0x03 # reenable interrupts b BASED(sysc_return) # # clone, fork, vfork, exec and sigreturn need glue, # because they all expect pt_regs as parameter, # but are called with different parameter. # return-address is set up above # sys_clone_glue: la %r2,SP_PTREGS(%r15) # load pt_regs l %r1,BASED(.Lclone) br %r1 # branch to sys_clone sys_fork_glue: la %r2,SP_PTREGS(%r15) # load pt_regs l %r1,BASED(.Lfork) br %r1 # branch to sys_fork sys_vfork_glue: la %r2,SP_PTREGS(%r15) # load pt_regs l %r1,BASED(.Lvfork) br %r1 # branch to sys_vfork sys_execve_glue: la %r2,SP_PTREGS(%r15) # load pt_regs l %r1,BASED(.Lexecve) lr %r12,%r14 # save return address basr %r14,%r1 # call sys_execve ltr %r2,%r2 # check if execve failed bnz 0(%r12) # it did fail -> store result in gpr2 b 4(%r12) # SKIP ST 2,SP_R2(15) after BASR 14,8 # in system_call/sysc_tracesys sys_sigreturn_glue: la %r2,SP_PTREGS(%r15) # load pt_regs as parameter l %r1,BASED(.Lsigreturn) br %r1 # branch to sys_sigreturn sys_rt_sigreturn_glue: la %r2,SP_PTREGS(%r15) # load pt_regs as parameter l %r1,BASED(.Lrt_sigreturn) br %r1 # branch to sys_sigreturn # # sigsuspend and rt_sigsuspend need pt_regs as an additional # parameter and they have to skip the store of %r2 into the # user register %r2 because the return value was set in # sigsuspend and rt_sigsuspend already and must not be overwritten! # sys_sigsuspend_glue: lr %r5,%r4 # move mask back lr %r4,%r3 # move history1 parameter lr %r3,%r2 # move history0 parameter la %r2,SP_PTREGS(%r15) # load pt_regs as first parameter l %r1,BASED(.Lsigsuspend) la %r14,4(%r14) # skip store of return value br %r1 # branch to sys_sigsuspend sys_rt_sigsuspend_glue: lr %r4,%r3 # move sigsetsize parameter lr %r3,%r2 # move unewset parameter la %r2,SP_PTREGS(%r15) # load pt_regs as first parameter l %r1,BASED(.Lrt_sigsuspend) la %r14,4(%r14) # skip store of return value br %r1 # branch to sys_rt_sigsuspend sys_sigaltstack_glue: la %r4,SP_PTREGS(%r15) # load pt_regs as parameter l %r1,BASED(.Lsigaltstack) br %r1 # branch to sys_sigreturn /* * Program check handler routine */ .globl pgm_check_handler pgm_check_handler: /* * First we need to check for a special case: * Single stepping an instruction that disables the PER event mask will * cause a PER event AFTER the mask has been set. Example: SVC or LPSW. * For a single stepped SVC the program check handler gets control after * the SVC new PSW has been loaded. But we want to execute the SVC first and * then handle the PER event. Therefore we update the SVC old PSW to point * to the pgm_check_handler and branch to the SVC handler after we checked * if we have to load the kernel stack register. * For every other possible cause for PER event without the PER mask set * we just ignore the PER event (FIXME: is there anything we have to do * for LPSW?). */ STORE_TIMER __LC_SYNC_ENTER_TIMER SAVE_ALL_BASE __LC_SAVE_AREA tm __LC_PGM_INT_CODE+1,0x80 # check whether we got a per exception bnz BASED(pgm_per) # got per exception -> special case SAVE_ALL __LC_PGM_OLD_PSW,__LC_SAVE_AREA,1 #ifdef CONFIG_VIRT_CPU_ACCOUNTING tm SP_PSW+1(%r15),0x01 # interrupting from user ? bz BASED(pgm_no_vtime) UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER pgm_no_vtime: #endif l %r9,__LC_THREAD_INFO # load pointer to thread_info struct l %r3,__LC_PGM_ILC # load program interruption code la %r8,0x7f nr %r8,%r3 pgm_do_call: l %r7,BASED(.Ljump_table) sll %r8,2 l %r7,0(%r8,%r7) # load address of handler routine la %r2,SP_PTREGS(%r15) # address of register-save area la %r14,BASED(sysc_return) br %r7 # branch to interrupt-handler # # handle per exception # pgm_per: tm __LC_PGM_OLD_PSW,0x40 # test if per event recording is on bnz BASED(pgm_per_std) # ok, normal per event from user space # ok its one of the special cases, now we need to find out which one clc __LC_PGM_OLD_PSW(8),__LC_SVC_NEW_PSW be BASED(pgm_svcper) # no interesting special case, ignore PER event lm %r12,%r15,__LC_SAVE_AREA lpsw 0x28 # # Normal per exception # pgm_per_std: SAVE_ALL __LC_PGM_OLD_PSW,__LC_SAVE_AREA,1 #ifdef CONFIG_VIRT_CPU_ACCOUNTING tm SP_PSW+1(%r15),0x01 # interrupting from user ? bz BASED(pgm_no_vtime2) UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER pgm_no_vtime2: #endif l %r9,__LC_THREAD_INFO # load pointer to thread_info struct l %r1,__TI_task(%r9) mvc __THREAD_per+__PER_atmid(2,%r1),__LC_PER_ATMID mvc __THREAD_per+__PER_address(4,%r1),__LC_PER_ADDRESS mvc __THREAD_per+__PER_access_id(1,%r1),__LC_PER_ACCESS_ID oi __TI_flags+3(%r9),_TIF_SINGLE_STEP # set TIF_SINGLE_STEP l %r3,__LC_PGM_ILC # load program interruption code la %r8,0x7f nr %r8,%r3 # clear per-event-bit and ilc be BASED(sysc_return) # only per or per+check ? b BASED(pgm_do_call) # # it was a single stepped SVC that is causing all the trouble # pgm_svcper: SAVE_ALL __LC_SVC_OLD_PSW,__LC_SAVE_AREA,1 #ifdef CONFIG_VIRT_CPU_ACCOUNTING tm SP_PSW+1(%r15),0x01 # interrupting from user ? bz BASED(pgm_no_vtime3) UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER pgm_no_vtime3: #endif lh %r7,0x8a # get svc number from lowcore l %r9,__LC_THREAD_INFO # load pointer to thread_info struct l %r1,__TI_task(%r9) mvc __THREAD_per+__PER_atmid(2,%r1),__LC_PER_ATMID mvc __THREAD_per+__PER_address(4,%r1),__LC_PER_ADDRESS mvc __THREAD_per+__PER_access_id(1,%r1),__LC_PER_ACCESS_ID oi __TI_flags+3(%r9),_TIF_SINGLE_STEP # set TIF_SINGLE_STEP stosm __SF_EMPTY(%r15),0x03 # reenable interrupts b BASED(sysc_do_svc) /* * IO interrupt handler routine */ .globl io_int_handler io_int_handler: STORE_TIMER __LC_ASYNC_ENTER_TIMER stck __LC_INT_CLOCK SAVE_ALL_BASE __LC_SAVE_AREA+16 SAVE_ALL __LC_IO_OLD_PSW,__LC_SAVE_AREA+16,0 #ifdef CONFIG_VIRT_CPU_ACCOUNTING tm SP_PSW+1(%r15),0x01 # interrupting from user ? bz BASED(io_no_vtime) UPDATE_VTIME __LC_EXIT_TIMER,__LC_ASYNC_ENTER_TIMER,__LC_USER_TIMER UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER mvc __LC_LAST_UPDATE_TIMER(8),__LC_ASYNC_ENTER_TIMER io_no_vtime: #endif l %r9,__LC_THREAD_INFO # load pointer to thread_info struct l %r1,BASED(.Ldo_IRQ) # load address of do_IRQ la %r2,SP_PTREGS(%r15) # address of register-save area basr %r14,%r1 # branch to standard irq handler io_return: tm SP_PSW+1(%r15),0x01 # returning to user ? #ifdef CONFIG_PREEMPT bno BASED(io_preempt) # no -> check for preemptive scheduling #else bno BASED(io_leave) # no-> skip resched & signal #endif tm __TI_flags+3(%r9),_TIF_WORK_INT bnz BASED(io_work) # there is work to do (signals etc.) io_leave: RESTORE_ALL 0 #ifdef CONFIG_PREEMPT io_preempt: icm %r0,15,__TI_precount(%r9) bnz BASED(io_leave) l %r1,SP_R15(%r15) s %r1,BASED(.Lc_spsize) mvc SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15) xc __SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1) # clear back chain lr %r15,%r1 io_resume_loop: tm __TI_flags+3(%r9),_TIF_NEED_RESCHED bno BASED(io_leave) mvc __TI_precount(4,%r9),BASED(.Lc_pactive) stosm __SF_EMPTY(%r15),0x03 # reenable interrupts l %r1,BASED(.Lschedule) basr %r14,%r1 # call schedule stnsm __SF_EMPTY(%r15),0xfc # disable I/O and ext. interrupts xc __TI_precount(4,%r9),__TI_precount(%r9) b BASED(io_resume_loop) #endif # # switch to kernel stack, then check the TIF bits # io_work: l %r1,__LC_KERNEL_STACK s %r1,BASED(.Lc_spsize) mvc SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15) xc __SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1) # clear back chain lr %r15,%r1 # # One of the work bits is on. Find out which one. # Checked are: _TIF_SIGPENDING and _TIF_NEED_RESCHED # io_work_loop: tm __TI_flags+3(%r9),_TIF_NEED_RESCHED bo BASED(io_reschedule) tm __TI_flags+3(%r9),_TIF_SIGPENDING bo BASED(io_sigpending) b BASED(io_leave) # # _TIF_NEED_RESCHED is set, call schedule # io_reschedule: l %r1,BASED(.Lschedule) stosm __SF_EMPTY(%r15),0x03 # reenable interrupts basr %r14,%r1 # call scheduler stnsm __SF_EMPTY(%r15),0xfc # disable I/O and ext. interrupts tm __TI_flags+3(%r9),_TIF_WORK_INT bz BASED(io_leave) # there is no work to do b BASED(io_work_loop) # # _TIF_SIGPENDING is set, call do_signal # io_sigpending: stosm __SF_EMPTY(%r15),0x03 # reenable interrupts la %r2,SP_PTREGS(%r15) # load pt_regs sr %r3,%r3 # clear *oldset l %r1,BASED(.Ldo_signal) basr %r14,%r1 # call do_signal stnsm __SF_EMPTY(%r15),0xfc # disable I/O and ext. interrupts b BASED(io_leave) # out of here, do NOT recheck /* * External interrupt handler routine */ .globl ext_int_handler ext_int_handler: STORE_TIMER __LC_ASYNC_ENTER_TIMER stck __LC_INT_CLOCK SAVE_ALL_BASE __LC_SAVE_AREA+16 SAVE_ALL __LC_EXT_OLD_PSW,__LC_SAVE_AREA+16,0 #ifdef CONFIG_VIRT_CPU_ACCOUNTING tm SP_PSW+1(%r15),0x01 # interrupting from user ? bz BASED(ext_no_vtime) UPDATE_VTIME __LC_EXIT_TIMER,__LC_ASYNC_ENTER_TIMER,__LC_USER_TIMER UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER mvc __LC_LAST_UPDATE_TIMER(8),__LC_ASYNC_ENTER_TIMER ext_no_vtime: #endif l %r9,__LC_THREAD_INFO # load pointer to thread_info struct la %r2,SP_PTREGS(%r15) # address of register-save area lh %r3,__LC_EXT_INT_CODE # get interruption code l %r1,BASED(.Ldo_extint) basr %r14,%r1 b BASED(io_return) /* * Machine check handler routines */ .globl mcck_int_handler mcck_int_handler: STORE_TIMER __LC_ASYNC_ENTER_TIMER SAVE_ALL_BASE __LC_SAVE_AREA+32 SAVE_ALL __LC_MCK_OLD_PSW,__LC_SAVE_AREA+32,0 #ifdef CONFIG_VIRT_CPU_ACCOUNTING tm SP_PSW+1(%r15),0x01 # interrupting from user ? bz BASED(mcck_no_vtime) UPDATE_VTIME __LC_EXIT_TIMER,__LC_ASYNC_ENTER_TIMER,__LC_USER_TIMER UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER mvc __LC_LAST_UPDATE_TIMER(8),__LC_ASYNC_ENTER_TIMER mcck_no_vtime: #endif l %r1,BASED(.Ls390_mcck) basr %r14,%r1 # call machine check handler mcck_return: RESTORE_ALL 0 #ifdef CONFIG_SMP /* * Restart interruption handler, kick starter for additional CPUs */ .globl restart_int_handler restart_int_handler: l %r15,__LC_SAVE_AREA+60 # load ksp lctl %c0,%c15,__LC_CREGS_SAVE_AREA # get new ctl regs lam %a0,%a15,__LC_AREGS_SAVE_AREA lm %r6,%r15,__SF_GPRS(%r15) # load registers from clone stosm __SF_EMPTY(%r15),0x04 # now we can turn dat on basr %r14,0 l %r14,restart_addr-.(%r14) br %r14 # branch to start_secondary restart_addr: .long start_secondary #else /* * If we do not run with SMP enabled, let the new CPU crash ... */ .globl restart_int_handler restart_int_handler: basr %r1,0 restart_base: lpsw restart_crash-restart_base(%r1) .align 8 restart_crash: .long 0x000a0000,0x00000000 restart_go: #endif #ifdef CONFIG_CHECK_STACK /* * The synchronous or the asynchronous stack overflowed. We are dead. * No need to properly save the registers, we are going to panic anyway. * Setup a pt_regs so that show_trace can provide a good call trace. */ stack_overflow: l %r15,__LC_PANIC_STACK # change to panic stack sl %r15,BASED(.Lc_spsize) mvc SP_PSW(8,%r15),0(%r12) # move user PSW to stack stm %r0,%r11,SP_R0(%r15) # store gprs %r0-%r11 to kernel stack la %r1,__LC_SAVE_AREA ch %r12,BASED(.L0x020) # old psw addr == __LC_SVC_OLD_PSW ? be BASED(0f) ch %r12,BASED(.L0x028) # old psw addr == __LC_PGM_OLD_PSW ? be BASED(0f) la %r1,__LC_SAVE_AREA+16 0: mvc SP_R12(16,%r15),0(%r1) # move %r12-%r15 to stack xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) # clear back chain l %r1,BASED(1f) # branch to kernel_stack_overflow la %r2,SP_PTREGS(%r15) # load pt_regs br %r1 1: .long kernel_stack_overflow #endif cleanup_table_system_call: .long system_call + 0x80000000, sysc_do_svc + 0x80000000 cleanup_table_sysc_return: .long sysc_return + 0x80000000, sysc_leave + 0x80000000 cleanup_table_sysc_leave: .long sysc_leave + 0x80000000, sysc_work_loop + 0x80000000 cleanup_table_sysc_work_loop: .long sysc_work_loop + 0x80000000, sysc_reschedule + 0x80000000 cleanup_critical: clc 4(4,%r12),BASED(cleanup_table_system_call) bl BASED(0f) clc 4(4,%r12),BASED(cleanup_table_system_call+4) bl BASED(cleanup_system_call) 0: clc 4(4,%r12),BASED(cleanup_table_sysc_return) bl BASED(0f) clc 4(4,%r12),BASED(cleanup_table_sysc_return+4) bl BASED(cleanup_sysc_return) 0: clc 4(4,%r12),BASED(cleanup_table_sysc_leave) bl BASED(0f) clc 4(4,%r12),BASED(cleanup_table_sysc_leave+4) bl BASED(cleanup_sysc_leave) 0: clc 4(4,%r12),BASED(cleanup_table_sysc_work_loop) bl BASED(0f) clc 4(4,%r12),BASED(cleanup_table_sysc_work_loop+4) bl BASED(cleanup_sysc_leave) 0: br %r14 cleanup_system_call: mvc __LC_RETURN_PSW(8),0(%r12) #ifdef CONFIG_VIRT_CPU_ACCOUNTING clc __LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn+4) bh BASED(0f) mvc __LC_SYNC_ENTER_TIMER(8),__LC_ASYNC_ENTER_TIMER 0: clc __LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn+8) bhe BASED(cleanup_vtime) #endif clc __LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn) bh BASED(0f) mvc __LC_SAVE_AREA(16),__LC_SAVE_AREA+16 0: st %r13,__LC_SAVE_AREA+20 SAVE_ALL __LC_SVC_OLD_PSW,__LC_SAVE_AREA,1 st %r15,__LC_SAVE_AREA+28 lh %r7,0x8a #ifdef CONFIG_VIRT_CPU_ACCOUNTING cleanup_vtime: clc __LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn+12) bhe BASED(cleanup_stime) tm SP_PSW+1(%r15),0x01 # interrupting from user ? bz BASED(cleanup_novtime) UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER cleanup_stime: clc __LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn+16) bh BASED(cleanup_update) UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER cleanup_update: mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER cleanup_novtime: #endif mvc __LC_RETURN_PSW+4(4),BASED(cleanup_table_system_call+4) la %r12,__LC_RETURN_PSW br %r14 cleanup_system_call_insn: .long sysc_saveall + 0x80000000 #ifdef CONFIG_VIRT_CPU_ACCOUNTING .long system_call + 0x80000000 .long sysc_vtime + 0x80000000 .long sysc_stime + 0x80000000 .long sysc_update + 0x80000000 #endif cleanup_sysc_return: mvc __LC_RETURN_PSW(4),0(%r12) mvc __LC_RETURN_PSW+4(4),BASED(cleanup_table_sysc_return) la %r12,__LC_RETURN_PSW br %r14 cleanup_sysc_leave: clc 4(4,%r12),BASED(cleanup_sysc_leave_insn) be BASED(0f) #ifdef CONFIG_VIRT_CPU_ACCOUNTING mvc __LC_EXIT_TIMER(8),__LC_ASYNC_ENTER_TIMER clc 4(4,%r12),BASED(cleanup_sysc_leave_insn+4) be BASED(0f) #endif mvc __LC_RETURN_PSW(8),SP_PSW(%r15) mvc __LC_SAVE_AREA+16(16),SP_R12(%r15) lm %r0,%r11,SP_R0(%r15) l %r15,SP_R15(%r15) 0: la %r12,__LC_RETURN_PSW br %r14 cleanup_sysc_leave_insn: #ifdef CONFIG_VIRT_CPU_ACCOUNTING .long sysc_leave + 14 + 0x80000000 #endif .long sysc_leave + 10 + 0x80000000 /* * Integer constants */ .align 4 .Lc_spsize: .long SP_SIZE .Lc_overhead: .long STACK_FRAME_OVERHEAD .Lc_pactive: .long PREEMPT_ACTIVE .Lnr_syscalls: .long NR_syscalls .L0x018: .short 0x018 .L0x020: .short 0x020 .L0x028: .short 0x028 .L0x030: .short 0x030 .L0x038: .short 0x038 .Lc_1: .long 1 /* * Symbol constants */ .Ls390_mcck: .long s390_do_machine_check .Ldo_IRQ: .long do_IRQ .Ldo_extint: .long do_extint .Ldo_signal: .long do_signal .Lhandle_per: .long do_single_step .Ljump_table: .long pgm_check_table .Lschedule: .long schedule .Lclone: .long sys_clone .Lexecve: .long sys_execve .Lfork: .long sys_fork .Lrt_sigreturn:.long sys_rt_sigreturn .Lrt_sigsuspend: .long sys_rt_sigsuspend .Lsigreturn: .long sys_sigreturn .Lsigsuspend: .long sys_sigsuspend .Lsigaltstack: .long sys_sigaltstack .Ltrace: .long syscall_trace .Lvfork: .long sys_vfork .Lschedtail: .long schedule_tail .Lcritical_start: .long __critical_start + 0x80000000 .Lcritical_end: .long __critical_end + 0x80000000 .Lcleanup_critical: .long cleanup_critical #define SYSCALL(esa,esame,emu) .long esa .globl sys_call_table sys_call_table: #include "syscalls.S" #undef SYSCALL