diff options
Diffstat (limited to 'arch/hexagon/kernel')
| -rw-r--r-- | arch/hexagon/kernel/process.c | 102 | ||||
| -rw-r--r-- | arch/hexagon/kernel/signal.c | 4 | ||||
| -rw-r--r-- | arch/hexagon/kernel/syscall.c | 44 | ||||
| -rw-r--r-- | arch/hexagon/kernel/vm_entry.S | 4 |
4 files changed, 39 insertions, 115 deletions
diff --git a/arch/hexagon/kernel/process.c b/arch/hexagon/kernel/process.c index 9f6d7411b574..cfbc52bd5227 100644 --- a/arch/hexagon/kernel/process.c +++ b/arch/hexagon/kernel/process.c @@ -26,33 +26,6 @@ #include <linux/slab.h> /* - * Kernel thread creation. The desired kernel function is "wrapped" - * in the kernel_thread_helper function, which does cleanup - * afterwards. - */ -static void __noreturn kernel_thread_helper(void *arg, int (*fn)(void *)) -{ - do_exit(fn(arg)); -} - -int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags) -{ - struct pt_regs regs; - - memset(®s, 0, sizeof(regs)); - /* - * Yes, we're exploting illicit knowledge of the ABI here. - */ - regs.r00 = (unsigned long) arg; - regs.r01 = (unsigned long) fn; - pt_set_elr(®s, (unsigned long)kernel_thread_helper); - pt_set_kmode(®s); - - return do_fork(flags|CLONE_VM|CLONE_UNTRACED, 0, ®s, 0, NULL, NULL); -} -EXPORT_SYMBOL(kernel_thread); - -/* * Program thread launch. Often defined as a macro in processor.h, * but we're shooting for a small footprint and it's not an inner-loop * performance-critical operation. @@ -114,7 +87,7 @@ unsigned long thread_saved_pc(struct task_struct *tsk) * Copy architecture-specific thread state */ int copy_thread(unsigned long clone_flags, unsigned long usp, - unsigned long unused, struct task_struct *p, + unsigned long arg, struct task_struct *p, struct pt_regs *regs) { struct thread_info *ti = task_thread_info(p); @@ -125,61 +98,50 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, childregs = (struct pt_regs *) (((unsigned long) ti + THREAD_SIZE) - sizeof(*childregs)); - memcpy(childregs, regs, sizeof(*childregs)); ti->regs = childregs; /* * Establish kernel stack pointer and initial PC for new thread + * Note that unlike the usual situation, we do not copy the + * parent's callee-saved here; those are in pt_regs and whatever + * we leave here will be overridden on return to userland. */ ss = (struct hexagon_switch_stack *) ((unsigned long) childregs - sizeof(*ss)); ss->lr = (unsigned long)ret_from_fork; p->thread.switch_sp = ss; - - /* If User mode thread, set pt_reg stack pointer as per parameter */ - if (user_mode(childregs)) { - pt_set_rte_sp(childregs, usp); - - /* Child sees zero return value */ - childregs->r00 = 0; - - /* - * The clone syscall has the C signature: - * int [r0] clone(int flags [r0], - * void *child_frame [r1], - * void *parent_tid [r2], - * void *child_tid [r3], - * void *thread_control_block [r4]); - * ugp is used to provide TLS support. - */ - if (clone_flags & CLONE_SETTLS) - childregs->ugp = childregs->r04; - - /* - * Parent sees new pid -- not necessary, not even possible at - * this point in the fork process - * Might also want to set things like ti->addr_limit - */ - } else { - /* - * If kernel thread, resume stack is kernel stack base. - * Note that this is pointer arithmetic on pt_regs * - */ - pt_set_rte_sp(childregs, (unsigned long)(childregs + 1)); - /* - * We need the current thread_info fast path pointer - * set up in pt_regs. The register to be used is - * parametric for assembler code, but the mechanism - * doesn't drop neatly into C. Needs to be fixed. - */ - childregs->THREADINFO_REG = (unsigned long) ti; + if (unlikely(p->flags & PF_KTHREAD)) { + memset(childregs, 0, sizeof(struct pt_regs)); + /* r24 <- fn, r25 <- arg */ + ss->r2524 = usp | ((u64)arg << 32); + pt_set_kmode(childregs); + return 0; } + memcpy(childregs, regs, sizeof(*childregs)); + ss->r2524 = 0; + + pt_set_rte_sp(childregs, usp); + + /* Child sees zero return value */ + childregs->r00 = 0; + + /* + * The clone syscall has the C signature: + * int [r0] clone(int flags [r0], + * void *child_frame [r1], + * void *parent_tid [r2], + * void *child_tid [r3], + * void *thread_control_block [r4]); + * ugp is used to provide TLS support. + */ + if (clone_flags & CLONE_SETTLS) + childregs->ugp = childregs->r04; /* - * thread_info pointer is pulled out of task_struct "stack" - * field on switch_to. + * Parent sees new pid -- not necessary, not even possible at + * this point in the fork process + * Might also want to set things like ti->addr_limit */ - p->stack = (void *)ti; return 0; } diff --git a/arch/hexagon/kernel/signal.c b/arch/hexagon/kernel/signal.c index 5047b8b879c0..fe0d1373165d 100644 --- a/arch/hexagon/kernel/signal.c +++ b/arch/hexagon/kernel/signal.c @@ -249,14 +249,14 @@ void do_notify_resume(struct pt_regs *regs, unsigned long thread_info_flags) */ asmlinkage int sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss) { - struct pt_regs *regs = current_thread_info()->regs; + struct pt_regs *regs = current_pt_regs(); return do_sigaltstack(uss, uoss, regs->r29); } asmlinkage int sys_rt_sigreturn(void) { - struct pt_regs *regs = current_thread_info()->regs; + struct pt_regs *regs = current_pt_regs(); struct rt_sigframe __user *frame; sigset_t blocked; diff --git a/arch/hexagon/kernel/syscall.c b/arch/hexagon/kernel/syscall.c index 319fa6494f58..d2cc3270af3e 100644 --- a/arch/hexagon/kernel/syscall.c +++ b/arch/hexagon/kernel/syscall.c @@ -35,55 +35,13 @@ * See signal.c for signal-related system call wrappers. */ -asmlinkage int sys_execve(char __user *ufilename, - const char __user *const __user *argv, - const char __user *const __user *envp) -{ - struct pt_regs *pregs = current_thread_info()->regs; - struct filename *filename; - int retval; - - filename = getname(ufilename); - retval = PTR_ERR(filename); - if (IS_ERR(filename)) - return retval; - - retval = do_execve(filename->name, argv, envp, pregs); - putname(filename); - - return retval; -} - asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp, unsigned long parent_tidp, unsigned long child_tidp) { - struct pt_regs *pregs = current_thread_info()->regs; + struct pt_regs *pregs = current_pt_regs(); if (!newsp) newsp = pregs->SP; return do_fork(clone_flags, newsp, pregs, 0, (int __user *)parent_tidp, (int __user *)child_tidp); } - -/* - * Do a system call from the kernel, so as to have a proper pt_regs - * and recycle the sys_execvpe infrustructure. - */ -int kernel_execve(const char *filename, - const char *const argv[], const char *const envp[]) -{ - register unsigned long __a0 asm("r0") = (unsigned long) filename; - register unsigned long __a1 asm("r1") = (unsigned long) argv; - register unsigned long __a2 asm("r2") = (unsigned long) envp; - int retval; - - __asm__ volatile( - " R6 = #%4;\n" - " trap0(#1);\n" - " %0 = R0;\n" - : "=r" (retval) - : "r" (__a0), "r" (__a1), "r" (__a2), "i" (__NR_execve) - ); - - return retval; -} diff --git a/arch/hexagon/kernel/vm_entry.S b/arch/hexagon/kernel/vm_entry.S index cd71673ac259..425e50c694f7 100644 --- a/arch/hexagon/kernel/vm_entry.S +++ b/arch/hexagon/kernel/vm_entry.S @@ -266,4 +266,8 @@ _K_enter_machcheck: .globl ret_from_fork ret_from_fork: call schedule_tail + P0 = cmp.eq(R24, #0); + if P0 jump return_from_syscall + R0 = R25; + callr R24 jump return_from_syscall |