Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S
new file mode 100644
index 0000000..c0e09b3
--- /dev/null
+++ b/arch/s390/kernel/entry.S
@@ -0,0 +1,868 @@
+/*
+ * 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 <linux/sys.h>
+#include <linux/linkage.h>
+#include <linux/config.h>
+#include <asm/cache.h>
+#include <asm/lowcore.h>
+#include <asm/errno.h>
+#include <asm/ptrace.h>
+#include <asm/thread_info.h>
+#include <asm/offsets.h>
+#include <asm/unistd.h>
+#include <asm/page.h>
+
+/*
+ * 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
+