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author | Linus Torvalds <torvalds@linux-foundation.org> | 2012-12-12 12:22:13 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-12-12 12:22:13 -0800 |
commit | 9977d9b379cb77e0f67bd6f4563618106e58e11d (patch) | |
tree | 0191accfddf578edb52c69c933d64521e3dce297 /arch/mips/kernel/process.c | |
parent | cf4af01221579a4e895f43dbfc47598fbfc5a731 (diff) | |
parent | 541880d9a2c7871f6370071d55aa6662d329c51e (diff) | |
download | linux-9977d9b379cb77e0f67bd6f4563618106e58e11d.tar.bz2 |
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/mips/kernel/process.c')
-rw-r--r-- | arch/mips/kernel/process.c | 64 |
1 files changed, 23 insertions, 41 deletions
diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c index e9a5fd7277f4..38097652d62d 100644 --- a/arch/mips/kernel/process.c +++ b/arch/mips/kernel/process.c @@ -84,6 +84,7 @@ void __noreturn cpu_idle(void) } asmlinkage void ret_from_fork(void); +asmlinkage void ret_from_kernel_thread(void); void start_thread(struct pt_regs * regs, unsigned long pc, unsigned long sp) { @@ -113,10 +114,10 @@ void flush_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; + struct pt_regs *childregs, *regs = current_pt_regs(); unsigned long childksp; p->set_child_tid = p->clear_child_tid = NULL; @@ -136,19 +137,30 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, childregs = (struct pt_regs *) childksp - 1; /* Put the stack after the struct pt_regs. */ childksp = (unsigned long) childregs; + p->thread.cp0_status = read_c0_status() & ~(ST0_CU2|ST0_CU1); + if (unlikely(p->flags & PF_KTHREAD)) { + unsigned long status = p->thread.cp0_status; + memset(childregs, 0, sizeof(struct pt_regs)); + ti->addr_limit = KERNEL_DS; + p->thread.reg16 = usp; /* fn */ + p->thread.reg17 = arg; + p->thread.reg29 = childksp; + p->thread.reg31 = (unsigned long) ret_from_kernel_thread; +#if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX) + status = (status & ~(ST0_KUP | ST0_IEP | ST0_IEC)) | + ((status & (ST0_KUC | ST0_IEC)) << 2); +#else + status |= ST0_EXL; +#endif + childregs->cp0_status = status; + return 0; + } *childregs = *regs; childregs->regs[7] = 0; /* Clear error flag */ - childregs->regs[2] = 0; /* Child gets zero as return value */ + childregs->regs[29] = usp; + ti->addr_limit = USER_DS; - if (childregs->cp0_status & ST0_CU0) { - childregs->regs[28] = (unsigned long) ti; - childregs->regs[29] = childksp; - ti->addr_limit = KERNEL_DS; - } else { - childregs->regs[29] = usp; - ti->addr_limit = USER_DS; - } p->thread.reg29 = (unsigned long) childregs; p->thread.reg31 = (unsigned long) ret_from_fork; @@ -156,7 +168,6 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, * New tasks lose permission to use the fpu. This accelerates context * switching for most programs since they don't use the fpu. */ - p->thread.cp0_status = read_c0_status() & ~(ST0_CU2|ST0_CU1); childregs->cp0_status &= ~(ST0_CU2|ST0_CU1); #ifdef CONFIG_MIPS_MT_SMTC @@ -222,35 +233,6 @@ int dump_task_fpu(struct task_struct *t, elf_fpregset_t *fpr) } /* - * Create a kernel thread - */ -static void __noreturn kernel_thread_helper(void *arg, int (*fn)(void *)) -{ - do_exit(fn(arg)); -} - -long kernel_thread(int (*fn)(void *), void *arg, unsigned long flags) -{ - struct pt_regs regs; - - memset(®s, 0, sizeof(regs)); - - regs.regs[4] = (unsigned long) arg; - regs.regs[5] = (unsigned long) fn; - regs.cp0_epc = (unsigned long) kernel_thread_helper; - regs.cp0_status = read_c0_status(); -#if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX) - regs.cp0_status = (regs.cp0_status & ~(ST0_KUP | ST0_IEP | ST0_IEC)) | - ((regs.cp0_status & (ST0_KUC | ST0_IEC)) << 2); -#else - regs.cp0_status |= ST0_EXL; -#endif - - /* Ok, create the new process.. */ - return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, ®s, 0, NULL, NULL); -} - -/* * */ struct mips_frame_info { |