sh: switch to generic kernel_thread()/kernel_execve()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index babc2b8..8451317 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -40,6 +40,8 @@
select GENERIC_STRNLEN_USER
select HAVE_MOD_ARCH_SPECIFIC if DWARF_UNWINDER
select MODULES_USE_ELF_RELA
+ select GENERIC_KERNEL_THREAD
+ select GENERIC_KERNEL_EXECVE
help
The SuperH is a RISC processor targeted for use in embedded systems
and consumer electronics; it was also used in the Sega Dreamcast
diff --git a/arch/sh/include/asm/processor_32.h b/arch/sh/include/asm/processor_32.h
index b6311fd..b1320d5 100644
--- a/arch/sh/include/asm/processor_32.h
+++ b/arch/sh/include/asm/processor_32.h
@@ -126,11 +126,6 @@
/* Free all resources held by a thread. */
extern void release_thread(struct task_struct *);
-/*
- * create a kernel thread without removing it from tasklists
- */
-extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
-
/* Copy and release all segment info associated with a VM */
#define copy_segments(p, mm) do { } while(0)
#define release_segments(mm) do { } while(0)
diff --git a/arch/sh/include/asm/processor_64.h b/arch/sh/include/asm/processor_64.h
index cd6029f..1ee8946 100644
--- a/arch/sh/include/asm/processor_64.h
+++ b/arch/sh/include/asm/processor_64.h
@@ -159,11 +159,6 @@
/* Free all resources held by a thread. */
extern void release_thread(struct task_struct *);
-/*
- * create a kernel thread without removing it from tasklists
- */
-extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
-
/* Copy and release all segment info associated with a VM */
#define copy_segments(p, mm) do { } while (0)
diff --git a/arch/sh/kernel/Makefile b/arch/sh/kernel/Makefile
index 88571ff..f259b37 100644
--- a/arch/sh/kernel/Makefile
+++ b/arch/sh/kernel/Makefile
@@ -16,7 +16,7 @@
machvec.o nmi_debug.o process.o \
process_$(BITS).o ptrace.o ptrace_$(BITS).o \
reboot.o return_address.o \
- setup.o signal_$(BITS).o sys_sh.o sys_sh$(BITS).o \
+ setup.o signal_$(BITS).o sys_sh.o \
syscalls_$(BITS).o time.o topology.o traps.o \
traps_$(BITS).o unwinder.o
@@ -25,6 +25,7 @@
obj-$(CONFIG_HAS_IOPORT) += ioport.o
endif
+obj-$(CONFIG_SUPERH32) += sys_sh32.o
obj-y += cpu/
obj-$(CONFIG_VSYSCALL) += vsyscall/
obj-$(CONFIG_SMP) += smp.o
diff --git a/arch/sh/kernel/cpu/sh5/entry.S b/arch/sh/kernel/cpu/sh5/entry.S
index 7e605b9..0c8d037 100644
--- a/arch/sh/kernel/cpu/sh5/entry.S
+++ b/arch/sh/kernel/cpu/sh5/entry.S
@@ -1228,6 +1228,25 @@
pta ret_from_syscall, tr0
blink tr0, ZERO
+.global ret_from_kernel_thread
+ret_from_kernel_thread:
+
+ movi schedule_tail,r5
+ ori r5, 1, r5
+ ptabs r5, tr0
+ blink tr0, LINK
+
+ ld.q SP, FRAME_R(2), r2
+ ld.q SP, FRAME_R(3), r3
+ ptabs r3, tr0
+ blink tr0, LINK
+
+ ld.q SP, FRAME_S(FSPC), r2
+ addi r2, 4, r2 /* Move PC, being pre-execution event */
+ st.q SP, FRAME_S(FSPC), r2
+ pta ret_from_syscall, tr0
+ blink tr0, ZERO
+
syscall_allowed:
/* Use LINK to deflect the exit point, default is syscall_ret */
pta syscall_ret, tr0
diff --git a/arch/sh/kernel/entry-common.S b/arch/sh/kernel/entry-common.S
index b96489d..9b6e4be 100644
--- a/arch/sh/kernel/entry-common.S
+++ b/arch/sh/kernel/entry-common.S
@@ -297,6 +297,19 @@
mov r0, r4
bra syscall_exit
nop
+
+ .align 2
+ .globl ret_from_kernel_thread
+ret_from_kernel_thread:
+ mov.l 1f, r8
+ jsr @r8
+ mov r0, r4
+ mov.l @(OFF_R5,r15), r5 ! fn
+ jsr @r5
+ mov.l @(OFF_R4,r15), r4 ! arg
+ bra syscall_exit
+ nop
+
.align 2
1: .long schedule_tail
diff --git a/arch/sh/kernel/process_32.c b/arch/sh/kernel/process_32.c
index ba7345f..b55070b 100644
--- a/arch/sh/kernel/process_32.c
+++ b/arch/sh/kernel/process_32.c
@@ -68,38 +68,6 @@
show_code(regs);
}
-/*
- * Create a kernel thread
- */
-__noreturn void kernel_thread_helper(void *arg, int (*fn)(void *))
-{
- do_exit(fn(arg));
-}
-
-/* Don't use this in BL=1(cli). Or else, CPU resets! */
-int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
-{
- struct pt_regs regs;
- int pid;
-
- memset(®s, 0, sizeof(regs));
- regs.regs[4] = (unsigned long)arg;
- regs.regs[5] = (unsigned long)fn;
-
- regs.pc = (unsigned long)kernel_thread_helper;
- regs.sr = SR_MD;
-#if defined(CONFIG_SH_FPU)
- regs.sr |= SR_FD;
-#endif
-
- /* Ok, create the new process.. */
- pid = do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0,
- ®s, 0, NULL, NULL);
-
- return pid;
-}
-EXPORT_SYMBOL(kernel_thread);
-
void start_thread(struct pt_regs *regs, unsigned long new_pc,
unsigned long new_sp)
{
@@ -157,9 +125,10 @@
EXPORT_SYMBOL(dump_fpu);
asmlinkage void ret_from_fork(void);
+asmlinkage void ret_from_kernel_thread(void);
int copy_thread(unsigned long clone_flags, unsigned long usp,
- unsigned long unused,
+ unsigned long arg,
struct task_struct *p, struct pt_regs *regs)
{
struct thread_info *ti = task_thread_info(p);
@@ -177,29 +146,34 @@
}
#endif
- childregs = task_pt_regs(p);
- *childregs = *regs;
+ memset(p->thread.ptrace_bps, 0, sizeof(p->thread.ptrace_bps));
- if (user_mode(regs)) {
- childregs->regs[15] = usp;
- ti->addr_limit = USER_DS;
- } else {
- childregs->regs[15] = (unsigned long)childregs;
+ childregs = task_pt_regs(p);
+ p->thread.sp = (unsigned long) childregs;
+ if (unlikely(p->flags & PF_KTHREAD)) {
+ memset(childregs, 0, sizeof(struct pt_regs));
+ p->thread.pc = (unsigned long) ret_from_kernel_thread;
+ childregs->regs[4] = arg;
+ childregs->regs[5] = usp;
+ childregs->sr = SR_MD;
+#if defined(CONFIG_SH_FPU)
+ childregs->sr |= SR_FD;
+#endif
ti->addr_limit = KERNEL_DS;
ti->status &= ~TS_USEDFPU;
p->fpu_counter = 0;
+ return 0;
}
+ *childregs = *regs;
+
+ childregs->regs[15] = usp;
+ ti->addr_limit = USER_DS;
if (clone_flags & CLONE_SETTLS)
childregs->gbr = childregs->regs[0];
childregs->regs[0] = 0; /* Set return value for child */
-
- p->thread.sp = (unsigned long) childregs;
p->thread.pc = (unsigned long) ret_from_fork;
-
- memset(p->thread.ptrace_bps, 0, sizeof(p->thread.ptrace_bps));
-
return 0;
}
diff --git a/arch/sh/kernel/process_64.c b/arch/sh/kernel/process_64.c
index 98a709f..fd338b0 100644
--- a/arch/sh/kernel/process_64.c
+++ b/arch/sh/kernel/process_64.c
@@ -285,39 +285,6 @@
}
/*
- * Create a kernel thread
- */
-__noreturn void kernel_thread_helper(void *arg, int (*fn)(void *))
-{
- do_exit(fn(arg));
-}
-
-/*
- * This is the mechanism for creating a new kernel thread.
- *
- * NOTE! Only a kernel-only process(ie the swapper or direct descendants
- * who haven't done an "execve()") should use this: it will work within
- * a system call from a "real" process, but the process memory space will
- * not be freed until both the parent and the child have exited.
- */
-int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
-{
- struct pt_regs regs;
-
- memset(®s, 0, sizeof(regs));
- regs.regs[2] = (unsigned long)arg;
- regs.regs[3] = (unsigned long)fn;
-
- regs.pc = (unsigned long)kernel_thread_helper;
- regs.sr = (1 << 30);
-
- /* Ok, create the new process.. */
- return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0,
- ®s, 0, NULL, NULL);
-}
-EXPORT_SYMBOL(kernel_thread);
-
-/*
* Free current thread data structures etc..
*/
void exit_thread(void)
@@ -401,15 +368,17 @@
EXPORT_SYMBOL(dump_fpu);
asmlinkage void ret_from_fork(void);
+asmlinkage void ret_from_kernel_thread(void);
int copy_thread(unsigned long clone_flags, unsigned long usp,
- unsigned long unused,
+ unsigned long arg,
struct task_struct *p, struct pt_regs *regs)
{
struct pt_regs *childregs;
#ifdef CONFIG_SH_FPU
- if(last_task_used_math == current) {
+ /* can't happen for a kernel thread */
+ if (last_task_used_math == current) {
enable_fpu();
save_fpu(current);
disable_fpu();
@@ -419,7 +388,17 @@
#endif
/* Copy from sh version */
childregs = (struct pt_regs *)(THREAD_SIZE + task_stack_page(p)) - 1;
+ p->thread.sp = (unsigned long) childregs;
+ if (unlikely(p->flags & PF_KTHREAD)) {
+ memset(childregs, 0, sizeof(struct pt_regs));
+ childregs->regs[2] = (unsigned long)arg;
+ childregs->regs[3] = (unsigned long)fn;
+ childregs->sr = (1 << 30); /* not user_mode */
+ childregs->sr |= SR_FD; /* Invalidate FPU flag */
+ p->thread.pc = (unsigned long) ret_from_kernel_thread;
+ return 0;
+ }
*childregs = *regs;
/*
@@ -428,19 +407,12 @@
* 32-bit wide and context switch must take care
* of NEFF sign extension.
*/
- if (user_mode(regs)) {
- childregs->regs[15] = neff_sign_extend(usp);
- p->thread.uregs = childregs;
- } else {
- childregs->regs[15] =
- neff_sign_extend((unsigned long)task_stack_page(p) +
- THREAD_SIZE);
- }
+ childregs->regs[15] = neff_sign_extend(usp);
+ p->thread.uregs = childregs;
childregs->regs[9] = 0; /* Set return value for child */
childregs->sr |= SR_FD; /* Invalidate FPU flag */
- p->thread.sp = (unsigned long) childregs;
p->thread.pc = (unsigned long) ret_from_fork;
return 0;
diff --git a/arch/sh/kernel/sys_sh32.c b/arch/sh/kernel/sys_sh32.c
index f56b6fe5..497bab3 100644
--- a/arch/sh/kernel/sys_sh32.c
+++ b/arch/sh/kernel/sys_sh32.c
@@ -60,27 +60,3 @@
(u64)len0 << 32 | len1, advice);
#endif
}
-
-#if defined(CONFIG_CPU_SH2) || defined(CONFIG_CPU_SH2A)
-#define SYSCALL_ARG3 "trapa #0x23"
-#else
-#define SYSCALL_ARG3 "trapa #0x13"
-#endif
-
-/*
- * Do a system call from kernel instead of calling sys_execve so we
- * end up with proper pt_regs.
- */
-int kernel_execve(const char *filename,
- const char *const argv[],
- const char *const envp[])
-{
- register long __sc0 __asm__ ("r3") = __NR_execve;
- register long __sc4 __asm__ ("r4") = (long) filename;
- register long __sc5 __asm__ ("r5") = (long) argv;
- register long __sc6 __asm__ ("r6") = (long) envp;
- __asm__ __volatile__ (SYSCALL_ARG3 : "=z" (__sc0)
- : "0" (__sc0), "r" (__sc4), "r" (__sc5), "r" (__sc6)
- : "memory");
- return __sc0;
-}
diff --git a/arch/sh/kernel/sys_sh64.c b/arch/sh/kernel/sys_sh64.c
deleted file mode 100644
index c5a38c4..0000000
--- a/arch/sh/kernel/sys_sh64.c
+++ /dev/null
@@ -1,50 +0,0 @@
-/*
- * arch/sh/kernel/sys_sh64.c
- *
- * Copyright (C) 2000, 2001 Paolo Alberelli
- *
- * This file contains various random system calls that
- * have a non-standard calling sequence on the Linux/SH5
- * platform.
- *
- * This file is subject to the terms and conditions of the GNU General Public
- * License. See the file "COPYING" in the main directory of this archive
- * for more details.
- */
-#include <linux/errno.h>
-#include <linux/rwsem.h>
-#include <linux/sched.h>
-#include <linux/mm.h>
-#include <linux/fs.h>
-#include <linux/smp.h>
-#include <linux/sem.h>
-#include <linux/msg.h>
-#include <linux/shm.h>
-#include <linux/stat.h>
-#include <linux/mman.h>
-#include <linux/file.h>
-#include <linux/syscalls.h>
-#include <linux/ipc.h>
-#include <asm/uaccess.h>
-#include <asm/ptrace.h>
-#include <asm/unistd.h>
-
-/*
- * Do a system call from kernel instead of calling sys_execve so we
- * end up with proper pt_regs.
- */
-int kernel_execve(const char *filename,
- const char *const argv[],
- const char *const envp[])
-{
- register unsigned long __sc0 __asm__ ("r9") = ((0x13 << 16) | __NR_execve);
- register unsigned long __sc2 __asm__ ("r2") = (unsigned long) filename;
- register unsigned long __sc3 __asm__ ("r3") = (unsigned long) argv;
- register unsigned long __sc4 __asm__ ("r4") = (unsigned long) envp;
- __asm__ __volatile__ ("trapa %1 !\t\t\t execve(%2,%3,%4)"
- : "=r" (__sc0)
- : "r" (__sc0), "r" (__sc2), "r" (__sc3), "r" (__sc4) );
- __asm__ __volatile__ ("!dummy %0 %1 %2 %3"
- : : "r" (__sc0), "r" (__sc2), "r" (__sc3), "r" (__sc4) : "memory");
- return __sc0;
-}