* 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_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_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_WORK_SVC = (_TIF_SIGPENDING | _TIF_NEED_RESCHED | \
+ _TIF_RESTART_SVC | _TIF_SINGLE_STEP )
_TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_NEED_RESCHED)
#define BASED(name) name-system_call(%r13)
lh %r7,0x8a # get svc number from lowcore
sysc_enter:
GET_THREAD_INFO # load pointer to task_struct to R9
+sysc_do_svc:
sla %r7,2 # *4 and test for svc 0
- bnz BASED(sysc_do_restart) # svc number > 0
+ bnz BASED(sysc_nr_ok) # svc number > 0
# svc 0: system call number in %r1
cl %r1,BASED(.Lnr_syscalls)
- bnl BASED(sysc_do_restart)
+ 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.
- bo BASED(sysc_tracesys)
+ 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
bz BASED(sysc_leave) # there is no work to do
#
# One of the work bits is on. Find out which one.
-# Checked are: _TIF_SIGPENDING and _TIF_NEED_RESCHED
#
sysc_work:
tm __TI_flags+3(%r9),_TIF_NEED_RESCHED
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)
#
lm %r2,%r6,SP_R2(%r15) # load svc arguments
b BASED(sysc_do_restart) # restart svc
+#
+# _TIF_SINGLE_STEP is set, call do_debugger_trap
+#
+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_debugger_trap
+
__critical_end:
#
st %r2,SP_R2(%r15) # store return value
sysc_tracenogo:
tm __TI_flags+3(%r9),(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT)
- bno BASED(sysc_return)
+ bz BASED(sysc_return)
l %r1,BASED(.Ltrace)
la %r2,SP_PTREGS(%r15) # load pt_regs
la %r3,1
pgm_per_std:
SAVE_ALL __LC_PGM_OLD_PSW,__LC_SAVE_AREA,1
GET_THREAD_INFO
- mvc __THREAD_per+__PER_atmid(2,%r9),__LC_PER_ATMID
- mvc __THREAD_per+__PER_address(4,%r9),__LC_PER_ADDRESS
- mvc __THREAD_per+__PER_access_id(1,%r9),__LC_PER_ACCESS_ID
+ 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
la %r4,0x7f
l %r3,__LC_PGM_ILC # load program interruption code
nr %r4,%r3 # clear per-event-bit and ilc
#
pgm_svcper:
SAVE_ALL __LC_SVC_OLD_PSW,__LC_SAVE_AREA,1
- lh %r7,0x8a # get svc number from lowcore
- stosm 24(%r15),0x03 # reenable interrupts
- GET_THREAD_INFO # load pointer to task_struct to R9
- mvc __THREAD_per+__PER_atmid(2,%r9),__LC_PER_ATMID
- mvc __THREAD_per+__PER_address(4,%r9),__LC_PER_ADDRESS
- mvc __THREAD_per+__PER_access_id(1,%r9),__LC_PER_ACCESS_ID
- sla %r7,2 # *4 and test for svc 0
- bnz BASED(pgm_svcstd) # svc number > 0 ?
- # svc 0: system call number in %r1
- cl %r1,BASED(.Lnr_syscalls)
- bnl BASED(pgm_svcstd)
- lr %r7,%r1 # copy svc number to %r7
- sla %r7,2 # *4
-pgm_svcstd:
- tm __TI_flags+3(%r9),(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT)
- l %r8,sys_call_table-system_call(%r7,%r13) # get system call addr.
- bo BASED(pgm_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 !!
-
-pgm_svcret:
- tm __TI_flags+3(%r9),_TIF_SIGPENDING
- bno BASED(pgm_svcper_nosig)
- la %r2,SP_PTREGS(%r15) # load pt_regs
- sr %r3,%r3 # clear *oldset
- l %r1,BASED(.Ldo_signal)
- basr %r14,%r1 # call do_signal
-
-pgm_svcper_nosig:
- mvi SP_TRAP+3(%r15),0x28 # set trap indication to pgm check
- la %r2,SP_PTREGS(15) # 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_debugger_trap
-#
-# call trace before and after sys_call
-#
-pgm_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(pgm_svc_nogo)
- l %r7,SP_R2(%r15) # strace changed the syscall
- sll %r7,2
- l %r8,sys_call_table-system_call(%r7,%r13)
-pgm_svc_go:
- 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
-pgm_svc_nogo:
- tm __TI_flags+3(%r9),(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT)
- bno BASED(pgm_svcret)
- l %r1,BASED(.Ltrace)
- la %r2,SP_PTREGS(%r15) # load pt_regs
- la %r3,1
- la %r14,BASED(pgm_svcret)
- br %r1
+ lh %r7,0x8a # get svc number from lowcore
+ GET_THREAD_INFO # load pointer to task_struct to R9
+ 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 24(%r15),0x03 # reenable interrupts
+ b BASED(sysc_do_svc)
/*
* IO interrupt handler routine