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-rw-r--r--arch/openrisc/kernel/Makefile2
-rw-r--r--arch/openrisc/kernel/asm-offsets.c6
-rw-r--r--arch/openrisc/kernel/entry.S73
-rw-r--r--arch/openrisc/kernel/head.S13
-rw-r--r--arch/openrisc/kernel/idle.c5
-rw-r--r--arch/openrisc/kernel/process.c164
-rw-r--r--arch/openrisc/kernel/signal.c17
-rw-r--r--arch/openrisc/kernel/sys_or32.c57
8 files changed, 102 insertions, 235 deletions
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..d8a455ede5a7 100644
--- a/arch/openrisc/kernel/entry.S
+++ b/arch/openrisc/kernel/entry.S
@@ -201,12 +201,17 @@ EXCEPTION_ENTRY(_bus_fault_handler)
l.nop
/* ---[ 0x300: Data Page Fault exception ]------------------------------- */
+EXCEPTION_ENTRY(_dtlb_miss_page_fault_handler)
+ l.and r5,r5,r0
+ l.j 1f
+ l.nop
EXCEPTION_ENTRY(_data_page_fault_handler)
/* set up parameters for do_page_fault */
+ l.ori r5,r0,0x300 // exception vector
+1:
l.addi r3,r1,0 // pt_regs
/* r4 set be EXCEPTION_HANDLE */ // effective address of fault
- l.ori r5,r0,0x300 // exception vector
/*
* __PHX__: TODO
@@ -276,12 +281,17 @@ EXCEPTION_ENTRY(_data_page_fault_handler)
l.nop
/* ---[ 0x400: Insn Page Fault exception ]------------------------------- */
+EXCEPTION_ENTRY(_itlb_miss_page_fault_handler)
+ l.and r5,r5,r0
+ l.j 1f
+ l.nop
EXCEPTION_ENTRY(_insn_page_fault_handler)
/* set up parameters for do_page_fault */
+ l.ori r5,r0,0x400 // exception vector
+1:
l.addi r3,r1,0 // pt_regs
/* r4 set be EXCEPTION_HANDLE */ // effective address of fault
- l.ori r5,r0,0x400 // exception vector
l.ori r6,r0,0x0 // !write access
/* call fault.c handler in or32/mm/fault.c */
@@ -894,6 +904,16 @@ 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 +935,6 @@ 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 +1044,13 @@ 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_TASK(r3) /* Load 'prev' as schedule_tail arg */
l.jr r9
l.nop
@@ -1076,26 +1081,18 @@ _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
-
ENTRY(sys_rt_sigreturn)
l.j _sys_rt_sigreturn
l.addi r3,r1,0
diff --git a/arch/openrisc/kernel/head.S b/arch/openrisc/kernel/head.S
index 1088b5fca3bd..1d3c9c28ac25 100644
--- a/arch/openrisc/kernel/head.S
+++ b/arch/openrisc/kernel/head.S
@@ -19,6 +19,7 @@
#include <linux/threads.h>
#include <linux/errno.h>
#include <linux/init.h>
+#include <linux/serial_reg.h>
#include <asm/processor.h>
#include <asm/page.h>
#include <asm/mmu.h>
@@ -291,9 +292,9 @@
/* Jump to .init code at _start which lives in the .head section
* and will be discarded after boot.
*/
- LOAD_SYMBOL_2_GPR(r4, _start)
- tophys (r3,r4) /* MMU disabled */
- l.jr r3
+ LOAD_SYMBOL_2_GPR(r15, _start)
+ tophys (r13,r15) /* MMU disabled */
+ l.jr r13
l.nop
/* ---[ 0x200: BUS exception ]------------------------------------------- */
@@ -1069,8 +1070,7 @@ d_pte_not_present:
EXCEPTION_LOAD_GPR4
EXCEPTION_LOAD_GPR5
EXCEPTION_LOAD_GPR6
- l.j _dispatch_do_dpage_fault
- l.nop
+ EXCEPTION_HANDLE(_dtlb_miss_page_fault_handler)
/* ==============================================[ ITLB miss handler ]=== */
ENTRY(itlb_miss_handler)
@@ -1192,8 +1192,7 @@ i_pte_not_present:
EXCEPTION_LOAD_GPR4
EXCEPTION_LOAD_GPR5
EXCEPTION_LOAD_GPR6
- l.j _dispatch_do_ipage_fault
- l.nop
+ EXCEPTION_HANDLE(_itlb_miss_page_fault_handler)
/* ==============================================[ boot tlb handlers ]=== */
diff --git a/arch/openrisc/kernel/idle.c b/arch/openrisc/kernel/idle.c
index 7d618feb1b72..5e8a3b6d6bc6 100644
--- a/arch/openrisc/kernel/idle.c
+++ b/arch/openrisc/kernel/idle.c
@@ -39,11 +39,6 @@
void (*powersave) (void) = NULL;
-static inline void pm_idle(void)
-{
- barrier();
-}
-
void cpu_idle(void)
{
set_thread_flag(TIF_POLLING_NRFLAG);
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..ae167f7e081a 100644
--- a/arch/openrisc/kernel/signal.c
+++ b/arch/openrisc/kernel/signal.c
@@ -33,12 +33,6 @@
#define DEBUG_SIG 0
-asmlinkage long
-_sys_sigaltstack(const stack_t *uss, stack_t *uoss, struct pt_regs *regs)
-{
- return do_sigaltstack(uss, uoss, regs->sp);
-}
-
struct rt_sigframe {
struct siginfo *pinfo;
void *puc;
@@ -84,7 +78,6 @@ 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 +97,8 @@ 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)))
+ if (restore_altstack(&frame->uc.uc_stack))
goto badframe;
- /* It is more difficult to avoid calling this function than to
- call it and ignore errors. */
- do_sigaltstack(&st, NULL, regs->sp);
return regs->gpr[11];
@@ -207,10 +197,7 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
err |= __clear_user(&frame->uc, offsetof(struct ucontext, uc_mcontext));
err |= __put_user(0, &frame->uc.uc_flags);
err |= __put_user(NULL, &frame->uc.uc_link);
- err |= __put_user((void *)current->sas_ss_sp,
- &frame->uc.uc_stack.ss_sp);
- err |= __put_user(sas_ss_flags(regs->sp), &frame->uc.uc_stack.ss_flags);
- err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
+ err |= __save_altstack(&frame->uc.uc_stack, regs->sp);
err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, set->sig[0]);
err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
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
-}
generated by cgit v1.2.3 (git 2.46.0) at 2025-08-22 08:19:10 +0000