14 files changed, 98 insertions, 216 deletions

diff --git a/arch/openrisc/Kconfig b/arch/openrisc/Kconfig
index 05f2ba41ff1a..0ac66f67521f 100644
--- a/arch/openrisc/Kconfig
+++ b/arch/openrisc/Kconfig
@@ -144,7 +144,7 @@ config DEBUG_STACKOVERFLOW
         help
           Make extra checks for space available on stack in some
           critical functions. This will cause kernel to run a bit slower,
-          but will catch most of kernel stack overruns and exit gracefuly.
+          but will catch most of kernel stack overruns and exit gracefully.
 
           Say Y if you are unsure.
 
diff --git a/arch/openrisc/Makefile b/arch/openrisc/Makefile
index 966886c8daf5..4739b8302a58 100644
--- a/arch/openrisc/Makefile
+++ b/arch/openrisc/Makefile
@@ -50,6 +50,6 @@ BUILTIN_DTB := y
 else
 BUILTIN_DTB := n
 endif
-core-$(BUILTIN_DTB) += arch/openrisc/boot/
+core-$(BUILTIN_DTB) += arch/openrisc/boot/dts/
 
 all: vmlinux
diff --git a/arch/openrisc/boot/Makefile b/arch/openrisc/boot/dts/Makefile
index 09958358601a..b092d30d6c23 100644
--- a/arch/openrisc/boot/Makefile
+++ b/arch/openrisc/boot/dts/Makefile
@@ -1,5 +1,3 @@
-
-
 ifneq '$(CONFIG_OPENRISC_BUILTIN_DTB)' '""'
 BUILTIN_DTB := $(patsubst "%",%,$(CONFIG_OPENRISC_BUILTIN_DTB)).dtb.o
 else
@@ -10,6 +8,3 @@ obj-y += $(BUILTIN_DTB)
 clean-files := *.dtb.S
 
 #DTC_FLAGS ?= -p 1024
-
-$(obj)/%.dtb: $(src)/dts/%.dts FORCE
-        $(call if_changed_dep,dtc)
diff --git a/arch/openrisc/include/asm/Kbuild b/arch/openrisc/include/asm/Kbuild
index 78de6805268d..f20d01d9aaf9 100644
--- a/arch/openrisc/include/asm/Kbuild
+++ b/arch/openrisc/include/asm/Kbuild
@@ -32,6 +32,7 @@ generic-y += ipcbuf.h
 generic-y += irq_regs.h
 generic-y += kdebug.h
 generic-y += kmap_types.h
+generic-y += kvm_para.h
 generic-y += local.h
 generic-y += mman.h
 generic-y += module.h
@@ -60,6 +61,7 @@ generic-y += swab.h
 generic-y += termbits.h
 generic-y += termios.h
 generic-y += topology.h
+generic-y += trace_clock.h
 generic-y += types.h
 generic-y += ucontext.h
 generic-y += user.h
diff --git a/arch/openrisc/include/asm/processor.h b/arch/openrisc/include/asm/processor.h
index 43decdbdb2ed..33691380608e 100644
--- a/arch/openrisc/include/asm/processor.h
+++ b/arch/openrisc/include/asm/processor.h
@@ -81,8 +81,6 @@ struct thread_struct {
 #define KSTK_ESP(tsk)   (task_pt_regs(tsk)->sp)
 
 
-extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
-
 void start_thread(struct pt_regs *regs, unsigned long nip, unsigned long sp);
 void release_thread(struct task_struct *);
 unsigned long get_wchan(struct task_struct *p);
diff --git a/arch/openrisc/include/asm/syscalls.h b/arch/openrisc/include/asm/syscalls.h
index 84a978af44d7..8ee816812a9e 100644
--- a/arch/openrisc/include/asm/syscalls.h
+++ b/arch/openrisc/include/asm/syscalls.h
@@ -24,4 +24,11 @@ asmlinkage long sys_or1k_atomic(unsigned long type, unsigned long *v1,
 
 #include <asm-generic/syscalls.h>
 
+asmlinkage long __sys_clone(unsigned long clone_flags, unsigned long newsp,
+                        void __user *parent_tid, void __user *child_tid, int tls);
+asmlinkage long __sys_fork(void);
+
+#define sys_clone __sys_clone
+#define sys_fork __sys_fork
+
 #endif /* __ASM_OPENRISC_SYSCALLS_H */
diff --git a/arch/openrisc/include/uapi/asm/kvm_para.h b/arch/openrisc/include/uapi/asm/kvm_para.h
deleted file mode 100644
index 14fab8f0b957..000000000000
--- a/arch/openrisc/include/uapi/asm/kvm_para.h
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/kvm_para.h>
diff --git a/arch/openrisc/include/uapi/asm/unistd.h b/arch/openrisc/include/uapi/asm/unistd.h
index 437bdbb61b14..ce40b71df006 100644
--- a/arch/openrisc/include/uapi/asm/unistd.h
+++ b/arch/openrisc/include/uapi/asm/unistd.h
@@ -20,6 +20,9 @@
 
 #define sys_mmap2 sys_mmap_pgoff
 
+#define __ARCH_WANT_SYS_FORK
+#define __ARCH_WANT_SYS_CLONE
+
 #include <asm-generic/unistd.h>
 
 #define __NR_or1k_atomic __NR_arch_specific_syscall
diff --git a/arch/openrisc/kernel/Makefile b/arch/openrisc/kernel/Makefile
index e1ee0fa2bbda..35f92ce51c24 100644
--- a/arch/openrisc/kernel/Makefile
+++ b/arch/openrisc/kernel/Makefile
@@ -5,7 +5,7 @@
 extra-y := head.o vmlinux.lds
 
 obj-y   := setup.o idle.o or32_ksyms.o process.o dma.o \
-           traps.o time.o irq.o entry.o ptrace.o signal.o sys_or32.o \
+           traps.o time.o irq.o entry.o ptrace.o signal.o \
            sys_call_table.o
 
 obj-$(CONFIG_MODULES)           += module.o
diff --git a/arch/openrisc/kernel/asm-offsets.c b/arch/openrisc/kernel/asm-offsets.c
index 1a242a0d7583..ddb736855863 100644
--- a/arch/openrisc/kernel/asm-offsets.c
+++ b/arch/openrisc/kernel/asm-offsets.c
@@ -34,15 +34,11 @@
 #include <linux/mm.h>
 #include <linux/io.h>
 #include <linux/thread_info.h>
+#include <linux/kbuild.h>
 #include <asm/page.h>
 #include <asm/pgtable.h>
 #include <asm/processor.h>
 
-#define DEFINE(sym, val) \
-                asm volatile("\n->" #sym " %0 " #val : : "i" (val))
-
-#define BLANK() asm volatile("\n->" : : )
-
 int main(void)
 {
         /* offsets into the task_struct */
diff --git a/arch/openrisc/kernel/entry.S b/arch/openrisc/kernel/entry.S
index ddfcaa828b0e..5e5b30601bbf 100644
--- a/arch/openrisc/kernel/entry.S
+++ b/arch/openrisc/kernel/entry.S
@@ -894,6 +894,16 @@ ENTRY(ret_from_fork)
         l.jal   schedule_tail
          l.nop
 
+        /* Check if we are a kernel thread */
+        l.sfeqi r20,0
+        l.bf    1f
+         l.nop
+
+        /* ...we are a kernel thread so invoke the requested callback */
+        l.jalr  r20
+         l.or   r3,r22,r0
+
+1:
         /* _syscall_returns expect r11 to contain return value */
         l.lwz   r11,PT_GPR11(r1)
 
@@ -915,26 +925,6 @@ ENTRY(ret_from_fork)
         l.j     _syscall_return
          l.nop
 
-/* Since syscalls don't save call-clobbered registers, the args to
- * kernel_thread_helper will need to be passed through callee-saved
- * registers and copied to the parameter registers when the thread
- * begins running.
- *
- * See arch/openrisc/kernel/process.c:
- * The args are passed as follows:
- *   arg1 (r3) : passed in r20
- *   arg2 (r4) : passed in r22
- */
-
-ENTRY(_kernel_thread_helper)
-        l.or    r3,r20,r0
-        l.or    r4,r22,r0
-        l.movhi r31,hi(kernel_thread_helper)
-        l.ori   r31,r31,lo(kernel_thread_helper)
-        l.jr    r31
-         l.nop
-
-
 /* ========================================================[ switch ] === */
 
 /*
@@ -1044,8 +1034,13 @@ ENTRY(_switch)
         /* Unwind stack to pre-switch state */
         l.addi  r1,r1,(INT_FRAME_SIZE)
 
-        /* Return via the link-register back to where we 'came from', where that can be
-         * either schedule() or return_from_fork()... */
+        /* Return via the link-register back to where we 'came from', where
+         * that may be either schedule(), ret_from_fork(), or
+         * ret_from_kernel_thread().  If we are returning to a new thread,
+         * we are expected to have set up the arg to schedule_tail already,
+         * hence we do so here unconditionally:
+         */
+        l.lwz   r3,TI_STACK(r3)         /* Load 'prev' as schedule_tail arg */
         l.jr    r9
          l.nop
 
@@ -1076,22 +1071,18 @@ _fork_save_extra_regs_and_call:
         l.jr    r29
          l.sw    PT_GPR28(r1),r28
 
-ENTRY(sys_clone)
-        l.movhi r29,hi(_sys_clone)
-        l.ori   r29,r29,lo(_sys_clone)
+ENTRY(__sys_clone)
+        l.movhi r29,hi(sys_clone)
+        l.ori   r29,r29,lo(sys_clone)
         l.j     _fork_save_extra_regs_and_call
          l.addi r7,r1,0
 
-ENTRY(sys_fork)
-        l.movhi r29,hi(_sys_fork)
-        l.ori   r29,r29,lo(_sys_fork)
+ENTRY(__sys_fork)
+        l.movhi r29,hi(sys_fork)
+        l.ori   r29,r29,lo(sys_fork)
         l.j     _fork_save_extra_regs_and_call
          l.addi r3,r1,0
 
-ENTRY(sys_execve)
-        l.j     _sys_execve
-         l.addi r6,r1,0
-
 ENTRY(sys_sigaltstack)
         l.j     _sys_sigaltstack
          l.addi r5,r1,0
diff --git a/arch/openrisc/kernel/process.c b/arch/openrisc/kernel/process.c
index c35f3ab1a8d3..00c233bf0d06 100644
--- a/arch/openrisc/kernel/process.c
+++ b/arch/openrisc/kernel/process.c
@@ -109,66 +109,83 @@ void release_thread(struct task_struct *dead_task)
  */
 extern asmlinkage void ret_from_fork(void);
 
+/*
+ * copy_thread
+ * @clone_flags: flags
+ * @usp: user stack pointer or fn for kernel thread
+ * @arg: arg to fn for kernel thread; always NULL for userspace thread
+ * @p: the newly created task
+ * @regs: CPU context to copy for userspace thread; always NULL for kthread
+ *
+ * At the top of a newly initialized kernel stack are two stacked pt_reg
+ * structures.  The first (topmost) is the userspace context of the thread.
+ * The second is the kernelspace context of the thread.
+ *
+ * A kernel thread will not be returning to userspace, so the topmost pt_regs
+ * struct can be uninitialized; it _does_ need to exist, though, because
+ * a kernel thread can become a userspace thread by doing a kernel_execve, in
+ * which case the topmost context will be initialized and used for 'returning'
+ * to userspace.
+ *
+ * The second pt_reg struct needs to be initialized to 'return' to
+ * ret_from_fork.  A kernel thread will need to set r20 to the address of
+ * a function to call into (with arg in r22); userspace threads need to set
+ * r20 to NULL in which case ret_from_fork will just continue a return to
+ * userspace.
+ *
+ * A kernel thread 'fn' may return; this is effectively what happens when
+ * kernel_execve is called.  In that case, the userspace pt_regs must have
+ * been initialized (which kernel_execve takes care of, see start_thread
+ * below); ret_from_fork will then continue its execution causing the
+ * 'kernel thread' to return to userspace as a userspace thread.
+ */
+
 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 pt_regs *childregs;
+        struct pt_regs *userregs;
         struct pt_regs *kregs;
         unsigned long sp = (unsigned long)task_stack_page(p) + THREAD_SIZE;
-        struct thread_info *ti;
         unsigned long top_of_kernel_stack;
 
         top_of_kernel_stack = sp;
 
         p->set_child_tid = p->clear_child_tid = NULL;
 
-        /* Copy registers */
-        /* redzone */
-        sp -= STACK_FRAME_OVERHEAD;
+        /* Locate userspace context on stack... */
+        sp -= STACK_FRAME_OVERHEAD;     /* redzone */
         sp -= sizeof(struct pt_regs);
-        childregs = (struct pt_regs *)sp;
+        userregs = (struct pt_regs *) sp;
 
-        /* Copy parent registers */
-        *childregs = *regs;
+        /* ...and kernel context */
+        sp -= STACK_FRAME_OVERHEAD;     /* redzone */
+        sp -= sizeof(struct pt_regs);
+        kregs = (struct pt_regs *)sp;
 
-        if ((childregs->sr & SPR_SR_SM) == 1) {
-                /* for kernel thread, set `current_thread_info'
-                 * and stackptr in new task
-                 */
-                childregs->sp = (unsigned long)task_stack_page(p) + THREAD_SIZE;
-                childregs->gpr[10] = (unsigned long)task_thread_info(p);
+        if (unlikely(p->flags & PF_KTHREAD)) {
+                memset(kregs, 0, sizeof(struct pt_regs));
+                kregs->gpr[20] = usp; /* fn, kernel thread */
+                kregs->gpr[22] = arg;
         } else {
-                childregs->sp = usp;
-        }
-
-        childregs->gpr[11] = 0; /* Result from fork() */
+                *userregs = *current_pt_regs();
 
-        /*
-         * The way this works is that at some point in the future
-         * some task will call _switch to switch to the new task.
-         * That will pop off the stack frame created below and start
-         * the new task running at ret_from_fork.  The new task will
-         * do some house keeping and then return from the fork or clone
-         * system call, using the stack frame created above.
-         */
-        /* redzone */
-        sp -= STACK_FRAME_OVERHEAD;
-        sp -= sizeof(struct pt_regs);
-        kregs = (struct pt_regs *)sp;
+                if (usp)
+                        userregs->sp = usp;
+                userregs->gpr[11] = 0;  /* Result from fork() */
 
-        ti = task_thread_info(p);
-        ti->ksp = sp;
+                kregs->gpr[20] = 0;     /* Userspace thread */
+        }
 
-        /* kregs->sp must store the location of the 'pre-switch' kernel stack
-         * pointer... for a newly forked process, this is simply the top of
-         * the kernel stack.
+        /*
+         * _switch wants the kernel stack page in pt_regs->sp so that it
+         * can restore it to thread_info->ksp... see _switch for details.
          */
         kregs->sp = top_of_kernel_stack;
-        kregs->gpr[3] = (unsigned long)current; /* arg to schedule_tail */
-        kregs->gpr[10] = (unsigned long)task_thread_info(p);
         kregs->gpr[9] = (unsigned long)ret_from_fork;
 
+        task_thread_info(p)->ksp = (unsigned long)kregs;
+
         return 0;
 }
 
@@ -177,16 +194,14 @@ copy_thread(unsigned long clone_flags, unsigned long usp,
  */
 void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long sp)
 {
-        unsigned long sr = regs->sr & ~SPR_SR_SM;
+        unsigned long sr = mfspr(SPR_SR) & ~SPR_SR_SM;
 
         set_fs(USER_DS);
-        memset(regs->gpr, 0, sizeof(regs->gpr));
+        memset(regs, 0, sizeof(struct pt_regs));
 
         regs->pc = pc;
         regs->sr = sr;
         regs->sp = sp;
-
-/*      printk("start thread, ksp = %lx\n", current_thread_info()->ksp);*/
 }
 
 /* Fill in the fpu structure for a core dump.  */
@@ -237,74 +252,9 @@ void dump_elf_thread(elf_greg_t *dest, struct pt_regs* regs)
         dest[35] = 0;
 }
 
-extern void _kernel_thread_helper(void);
-
-void __noreturn kernel_thread_helper(int (*fn) (void *), void *arg)
-{
-        do_exit(fn(arg));
-}
-
-/*
- * Create a kernel thread.
- */
-int kernel_thread(int (*fn) (void *), void *arg, unsigned long flags)
-{
-        struct pt_regs regs;
-
-        memset(&regs, 0, sizeof(regs));
-
-        regs.gpr[20] = (unsigned long)fn;
-        regs.gpr[22] = (unsigned long)arg;
-        regs.sr = mfspr(SPR_SR);
-        regs.pc = (unsigned long)_kernel_thread_helper;
-
-        return do_fork(flags | CLONE_VM | CLONE_UNTRACED,
-                       0, &regs, 0, NULL, NULL);
-}
-
-/*
- * sys_execve() executes a new program.
- */
-asmlinkage long _sys_execve(const char __user *name,
-                            const char __user * const __user *argv,
-                            const char __user * const __user *envp,
-                            struct pt_regs *regs)
-{
-        int error;
-        struct filename *filename;
-
-        filename = getname(name);
-        error = PTR_ERR(filename);
-
-        if (IS_ERR(filename))
-                goto out;
-
-        error = do_execve(filename->name, argv, envp, regs);
-        putname(filename);
-
-out:
-        return error;
-}
-
 unsigned long get_wchan(struct task_struct *p)
 {
         /* TODO */
 
         return 0;
 }
-
-int kernel_execve(const char *filename, char *const argv[], char *const envp[])
-{
-        register long __res asm("r11") = __NR_execve;
-        register long __a asm("r3") = (long)(filename);
-        register long __b asm("r4") = (long)(argv);
-        register long __c asm("r5") = (long)(envp);
-        __asm__ volatile ("l.sys 1"
-                          : "=r" (__res), "=r"(__a), "=r"(__b), "=r"(__c)
-                          : "0"(__res), "1"(__a), "2"(__b), "3"(__c)
-                          : "r6", "r7", "r8", "r12", "r13", "r15",
-                            "r17", "r19", "r21", "r23", "r25", "r27",
-                            "r29", "r31");
-        __asm__ volatile ("l.nop");
-        return __res;
-}
diff --git a/arch/openrisc/kernel/signal.c b/arch/openrisc/kernel/signal.c
index 30110297f4f9..ddedc8a77861 100644
--- a/arch/openrisc/kernel/signal.c
+++ b/arch/openrisc/kernel/signal.c
@@ -84,7 +84,6 @@ asmlinkage long _sys_rt_sigreturn(struct pt_regs *regs)
 {
         struct rt_sigframe *frame = (struct rt_sigframe __user *)regs->sp;
         sigset_t set;
-        stack_t st;
 
         /*
          * Since we stacked the signal on a dword boundary,
@@ -104,11 +103,10 @@ asmlinkage long _sys_rt_sigreturn(struct pt_regs *regs)
         if (restore_sigcontext(regs, &frame->uc.uc_mcontext))
                 goto badframe;
 
-        if (__copy_from_user(&st, &frame->uc.uc_stack, sizeof(st)))
-                goto badframe;
         /* It is more difficult to avoid calling this function than to
            call it and ignore errors.  */
-        do_sigaltstack(&st, NULL, regs->sp);
+        if (do_sigaltstack(&frame->uc.uc_stack, NULL, regs->sp) == -EFAULT)
+                goto badframe;
 
         return regs->gpr[11];
 
diff --git a/arch/openrisc/kernel/sys_or32.c b/arch/openrisc/kernel/sys_or32.c
deleted file mode 100644
index 57060084c0cc..000000000000
--- a/arch/openrisc/kernel/sys_or32.c
+++ /dev/null
@@ -1,57 +0,0 @@
-/*
- * OpenRISC sys_or32.c
- *
- * Linux architectural port borrowing liberally from similar works of
- * others.  All original copyrights apply as per the original source
- * declaration.
- *
- * Modifications for the OpenRISC architecture:
- * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
- * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
- *
- *      This program is free software; you can redistribute it and/or
- *      modify it under the terms of the GNU General Public License
- *      as published by the Free Software Foundation; either version
- *      2 of the License, or (at your option) any later version.
- *
- * This file contains various random system calls that
- * have a non-standard calling sequence on some platforms.
- * Since we don't have to do any backwards compatibility, our
- * versions are done in the most "normal" way possible.
- */
-
-#include <linux/errno.h>
-#include <linux/syscalls.h>
-#include <linux/mm.h>
-
-#include <asm/syscalls.h>
-
-/* These are secondary entry points as the primary entry points are defined in
- * entry.S where we add the 'regs' parameter value
- */
-
-asmlinkage long _sys_clone(unsigned long clone_flags, unsigned long newsp,
-                           int __user *parent_tid, int __user *child_tid,
-                           struct pt_regs *regs)
-{
-        long ret;
-
-        /* FIXME: Is alignment necessary? */
-        /* newsp = ALIGN(newsp, 4); */
-
-        if (!newsp)
-                newsp = regs->sp;
-
-        ret = do_fork(clone_flags, newsp, regs, 0, parent_tid, child_tid);
-
-        return ret;
-}
-
-asmlinkage int _sys_fork(struct pt_regs *regs)
-{
-#ifdef CONFIG_MMU
-        return do_fork(SIGCHLD, regs->sp, regs, 0, NULL, NULL);
-#else
-        return -EINVAL;
-#endif
-}