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author | Linus Torvalds <torvalds@linux-foundation.org> | 2012-12-12 21:22:13 +0100 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-12-12 21:22:13 +0100 |
commit | 9977d9b379cb77e0f67bd6f4563618106e58e11d (patch) | |
tree | 0191accfddf578edb52c69c933d64521e3dce297 /arch/sh/kernel/process_32.c | |
parent | Merge tag 'boards' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc (diff) | |
parent | do_coredump(): get rid of pt_regs argument (diff) | |
download | linux-9977d9b379cb77e0f67bd6f4563618106e58e11d.tar.xz linux-9977d9b379cb77e0f67bd6f4563618106e58e11d.zip |
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal
Pull big execve/kernel_thread/fork unification series from Al Viro:
"All architectures are converted to new model. Quite a bit of that
stuff is actually shared with architecture trees; in such cases it's
literally shared branch pulled by both, not a cherry-pick.
A lot of ugliness and black magic is gone (-3KLoC total in this one):
- kernel_thread()/kernel_execve()/sys_execve() redesign.
We don't do syscalls from kernel anymore for either kernel_thread()
or kernel_execve():
kernel_thread() is essentially clone(2) with callback run before we
return to userland, the callbacks either never return or do
successful do_execve() before returning.
kernel_execve() is a wrapper for do_execve() - it doesn't need to
do transition to user mode anymore.
As a result kernel_thread() and kernel_execve() are
arch-independent now - they live in kernel/fork.c and fs/exec.c
resp. sys_execve() is also in fs/exec.c and it's completely
architecture-independent.
- daemonize() is gone, along with its parts in fs/*.c
- struct pt_regs * is no longer passed to do_fork/copy_process/
copy_thread/do_execve/search_binary_handler/->load_binary/do_coredump.
- sys_fork()/sys_vfork()/sys_clone() unified; some architectures
still need wrappers (ones with callee-saved registers not saved in
pt_regs on syscall entry), but the main part of those suckers is in
kernel/fork.c now."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (113 commits)
do_coredump(): get rid of pt_regs argument
print_fatal_signal(): get rid of pt_regs argument
ptrace_signal(): get rid of unused arguments
get rid of ptrace_signal_deliver() arguments
new helper: signal_pt_regs()
unify default ptrace_signal_deliver
flagday: kill pt_regs argument of do_fork()
death to idle_regs()
don't pass regs to copy_process()
flagday: don't pass regs to copy_thread()
bfin: switch to generic vfork, get rid of pointless wrappers
xtensa: switch to generic clone()
openrisc: switch to use of generic fork and clone
unicore32: switch to generic clone(2)
score: switch to generic fork/vfork/clone
c6x: sanitize copy_thread(), get rid of clone(2) wrapper, switch to generic clone()
take sys_fork/sys_vfork/sys_clone prototypes to linux/syscalls.h
mn10300: switch to generic fork/vfork/clone
h8300: switch to generic fork/vfork/clone
tile: switch to generic clone()
...
Conflicts:
arch/microblaze/include/asm/Kbuild
Diffstat (limited to 'arch/sh/kernel/process_32.c')
-rw-r--r-- | arch/sh/kernel/process_32.c | 134 |
1 files changed, 20 insertions, 114 deletions
diff --git a/arch/sh/kernel/process_32.c b/arch/sh/kernel/process_32.c index ba7345f37bc9..73eb66fc6253 100644 --- a/arch/sh/kernel/process_32.c +++ b/arch/sh/kernel/process_32.c @@ -68,38 +68,6 @@ void show_regs(struct pt_regs * regs) 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) { @@ -157,10 +125,10 @@ int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu) 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, - struct task_struct *p, struct pt_regs *regs) + unsigned long arg, struct task_struct *p) { struct thread_info *ti = task_thread_info(p); struct pt_regs *childregs; @@ -177,29 +145,35 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, } #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 = *current_pt_regs(); + + if (usp) + 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; } @@ -243,74 +217,6 @@ __switch_to(struct task_struct *prev, struct task_struct *next) return prev; } -asmlinkage int sys_fork(unsigned long r4, unsigned long r5, - unsigned long r6, unsigned long r7, - struct pt_regs __regs) -{ -#ifdef CONFIG_MMU - struct pt_regs *regs = RELOC_HIDE(&__regs, 0); - return do_fork(SIGCHLD, regs->regs[15], regs, 0, NULL, NULL); -#else - /* fork almost works, enough to trick you into looking elsewhere :-( */ - return -EINVAL; -#endif -} - -asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp, - unsigned long parent_tidptr, - unsigned long child_tidptr, - struct pt_regs __regs) -{ - struct pt_regs *regs = RELOC_HIDE(&__regs, 0); - if (!newsp) - newsp = regs->regs[15]; - return do_fork(clone_flags, newsp, regs, 0, - (int __user *)parent_tidptr, - (int __user *)child_tidptr); -} - -/* - * This is trivial, and on the face of it looks like it - * could equally well be done in user mode. - * - * Not so, for quite unobvious reasons - register pressure. - * In user mode vfork() cannot have a stack frame, and if - * done by calling the "clone()" system call directly, you - * do not have enough call-clobbered registers to hold all - * the information you need. - */ -asmlinkage int sys_vfork(unsigned long r4, unsigned long r5, - unsigned long r6, unsigned long r7, - struct pt_regs __regs) -{ - struct pt_regs *regs = RELOC_HIDE(&__regs, 0); - return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->regs[15], regs, - 0, NULL, NULL); -} - -/* - * sys_execve() executes a new program. - */ -asmlinkage int sys_execve(const char __user *ufilename, - const char __user *const __user *uargv, - const char __user *const __user *uenvp, - unsigned long r7, struct pt_regs __regs) -{ - struct pt_regs *regs = RELOC_HIDE(&__regs, 0); - int error; - struct filename *filename; - - filename = getname(ufilename); - error = PTR_ERR(filename); - if (IS_ERR(filename)) - goto out; - - error = do_execve(filename->name, uargv, uenvp, regs); - putname(filename); -out: - return error; -} - unsigned long get_wchan(struct task_struct *p) { unsigned long pc; |