Commit c660b8f9 authored by Linus Torvalds's avatar Linus Torvalds

Merge tag 'xtensa-next-20121101' of git://github.com/czankel/xtensa-linux

Pull Xtensa fixes from Chris Zankel:
 "Some important bug fixes.

  With the change to uapi, there was a bug introduced that results in an
  empty syscall table (mult-inclusion bug).  Switching to the generic
  thread/execve allowed us to fix a bug we had in vfork()."

* tag 'xtensa-next-20121101' of git://github.com/czankel/xtensa-linux:
  xtensa: switch to generic sys_execve()
  xtensa: switch to generic kernel_execve()
  xtensa: switch to generic kernel_thread()
  xtensa: reset windowbase/windowstart when cloning the VM
  xtensa: use physical addresses for bus addresses
  xtensa: allow multi-inclusion for uapi/unistd.h
parents 8c23f406 dc241f2c
......@@ -13,6 +13,8 @@ config XTENSA
select GENERIC_CPU_DEVICES
select MODULES_USE_ELF_RELA
select GENERIC_PCI_IOMAP
select GENERIC_KERNEL_THREAD
select GENERIC_KERNEL_EXECVE
select ARCH_WANT_OPTIONAL_GPIOLIB
help
Xtensa processors are 32-bit RISC machines designed by Tensilica
......
......@@ -62,6 +62,10 @@ static inline void __iomem *ioremap(unsigned long offset, unsigned long size)
static inline void iounmap(volatile void __iomem *addr)
{
}
#define virt_to_bus virt_to_phys
#define bus_to_virt phys_to_virt
#endif /* CONFIG_MMU */
/*
......
......@@ -152,6 +152,7 @@ struct thread_struct {
/* Clearing a0 terminates the backtrace. */
#define start_thread(regs, new_pc, new_sp) \
memset(regs, 0, sizeof(*regs)); \
regs->pc = new_pc; \
regs->ps = USER_PS_VALUE; \
regs->areg[1] = new_sp; \
......@@ -168,9 +169,6 @@ struct mm_struct;
/* Free all resources held by a thread. */
#define release_thread(thread) do { } while(0)
/* Create a kernel thread without removing it from tasklists */
extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
/* Copy and release all segment info associated with a VM */
#define copy_segments(p, mm) do { } while(0)
#define release_segments(mm) do { } while(0)
......
......@@ -10,7 +10,7 @@
struct pt_regs;
struct sigaction;
asmlinkage long xtensa_execve(char*, char**, char**, struct pt_regs*);
asmlinkage long sys_execve(char*, char**, char**, struct pt_regs*);
asmlinkage long xtensa_clone(unsigned long, unsigned long, struct pt_regs*);
asmlinkage long xtensa_ptrace(long, long, long, long);
asmlinkage long xtensa_sigreturn(struct pt_regs*);
......
/*
* include/asm-xtensa/unistd.h
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2001 - 2005 Tensilica Inc.
*/
#ifndef _XTENSA_UNISTD_H
#define _XTENSA_UNISTD_H
#define __ARCH_WANT_SYS_EXECVE
#include <uapi/asm/unistd.h>
/*
* "Conditional" syscalls
*
......@@ -37,3 +30,5 @@
#define __IGNORE_mmap /* use mmap2 */
#define __IGNORE_vfork /* use clone */
#define __IGNORE_fadvise64 /* use fadvise64_64 */
#endif /* _XTENSA_UNISTD_H */
/*
* include/asm-xtensa/unistd.h
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2001 - 2012 Tensilica Inc.
*/
#ifndef _UAPI_XTENSA_UNISTD_H
#if !defined(_UAPI_XTENSA_UNISTD_H) || defined(__SYSCALL)
#define _UAPI_XTENSA_UNISTD_H
#ifndef __SYSCALL
......@@ -272,7 +262,7 @@ __SYSCALL(115, sys_sendmmsg, 4)
#define __NR_clone 116
__SYSCALL(116, xtensa_clone, 5)
#define __NR_execve 117
__SYSCALL(117, xtensa_execve, 3)
__SYSCALL(117, sys_execve, 3)
#define __NR_exit 118
__SYSCALL(118, sys_exit, 1)
#define __NR_exit_group 119
......@@ -759,4 +749,6 @@ __SYSCALL(331, sys_kcmp, 5)
#define SYS_XTENSA_COUNT 5 /* count */
#undef __SYSCALL
#endif /* _UAPI_XTENSA_UNISTD_H */
......@@ -1832,50 +1832,6 @@ ENTRY(system_call)
retw
/*
* Create a kernel thread
*
* int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
* a2 a2 a3 a4
*/
ENTRY(kernel_thread)
entry a1, 16
mov a5, a2 # preserve fn over syscall
mov a7, a3 # preserve args over syscall
movi a3, _CLONE_VM | _CLONE_UNTRACED
movi a2, __NR_clone
or a6, a4, a3 # arg0: flags
mov a3, a1 # arg1: sp
syscall
beq a3, a1, 1f # branch if parent
mov a6, a7 # args
callx4 a5 # fn(args)
movi a2, __NR_exit
syscall # return value of fn(args) still in a6
1: retw
/*
* Do a system call from kernel instead of calling sys_execve, so we end up
* with proper pt_regs.
*
* int kernel_execve(const char *fname, char *const argv[], charg *const envp[])
* a2 a2 a3 a4
*/
ENTRY(kernel_execve)
entry a1, 16
mov a6, a2 # arg0 is in a6
movi a2, __NR_execve
syscall
retw
/*
* Task switch.
*
......@@ -1958,3 +1914,16 @@ ENTRY(ret_from_fork)
j common_exception_return
/*
* Kernel thread creation helper
* On entry, set up by copy_thread: a2 = thread_fn, a3 = thread_fn arg
* left from _switch_to: a6 = prev
*/
ENTRY(ret_from_kernel_thread)
call4 schedule_tail
mov a6, a3
callx4 a2
j common_exception_return
ENDPROC(ret_from_kernel_thread)
......@@ -45,6 +45,7 @@
#include <asm/regs.h>
extern void ret_from_fork(void);
extern void ret_from_kernel_thread(void);
struct task_struct *current_set[NR_CPUS] = {&init_task, };
......@@ -158,18 +159,30 @@ int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
/*
* Copy thread.
*
* There are two modes in which this function is called:
* 1) Userspace thread creation,
* regs != NULL, usp_thread_fn is userspace stack pointer.
* It is expected to copy parent regs (in case CLONE_VM is not set
* in the clone_flags) and set up passed usp in the childregs.
* 2) Kernel thread creation,
* regs == NULL, usp_thread_fn is the function to run in the new thread
* and thread_fn_arg is its parameter.
* childregs are not used for the kernel threads.
*
* The stack layout for the new thread looks like this:
*
* +------------------------+ <- sp in childregs (= tos)
* +------------------------+
* | childregs |
* +------------------------+ <- thread.sp = sp in dummy-frame
* | dummy-frame | (saved in dummy-frame spill-area)
* +------------------------+
*
* We create a dummy frame to return to ret_from_fork:
* a0 points to ret_from_fork (simulating a call4)
* We create a dummy frame to return to either ret_from_fork or
* ret_from_kernel_thread:
* a0 points to ret_from_fork/ret_from_kernel_thread (simulating a call4)
* sp points to itself (thread.sp)
* a2, a3 are unused.
* a2, a3 are unused for userspace threads,
* a2 points to thread_fn, a3 holds thread_fn arg for kernel threads.
*
* Note: This is a pristine frame, so we don't need any spill region on top of
* childregs.
......@@ -185,43 +198,63 @@ int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
* involved. Much simpler to just not copy those live frames across.
*/
int copy_thread(unsigned long clone_flags, unsigned long usp,
unsigned long unused,
struct task_struct * p, struct pt_regs * regs)
int copy_thread(unsigned long clone_flags, unsigned long usp_thread_fn,
unsigned long thread_fn_arg,
struct task_struct *p, struct pt_regs *unused)
{
struct pt_regs *childregs;
unsigned long tos;
int user_mode = user_mode(regs);
struct pt_regs *childregs = task_pt_regs(p);
#if (XTENSA_HAVE_COPROCESSORS || XTENSA_HAVE_IO_PORTS)
struct thread_info *ti;
#endif
/* Set up new TSS. */
tos = (unsigned long)task_stack_page(p) + THREAD_SIZE;
if (user_mode)
childregs = (struct pt_regs*)(tos - PT_USER_SIZE);
else
childregs = (struct pt_regs*)tos - 1;
/* This does not copy all the regs. In a bout of brilliance or madness,
ARs beyond a0-a15 exist past the end of the struct. */
*childregs = *regs;
/* Create a call4 dummy-frame: a0 = 0, a1 = childregs. */
*((int*)childregs - 3) = (unsigned long)childregs;
*((int*)childregs - 4) = 0;
childregs->areg[2] = 0;
p->set_child_tid = p->clear_child_tid = NULL;
p->thread.ra = MAKE_RA_FOR_CALL((unsigned long)ret_from_fork, 0x1);
p->thread.sp = (unsigned long)childregs;
if (user_mode(regs)) {
if (!(p->flags & PF_KTHREAD)) {
struct pt_regs *regs = current_pt_regs();
unsigned long usp = usp_thread_fn ?
usp_thread_fn : regs->areg[1];
p->thread.ra = MAKE_RA_FOR_CALL(
(unsigned long)ret_from_fork, 0x1);
/* This does not copy all the regs.
* In a bout of brilliance or madness,
* ARs beyond a0-a15 exist past the end of the struct.
*/
*childregs = *regs;
childregs->areg[1] = usp;
childregs->areg[2] = 0;
/* When sharing memory with the parent thread, the child
usually starts on a pristine stack, so we have to reset
windowbase, windowstart and wmask.
(Note that such a new thread is required to always create
an initial call4 frame)
The exception is vfork, where the new thread continues to
run on the parent's stack until it calls execve. This could
be a call8 or call12, which requires a legal stack frame
of the previous caller for the overflow handlers to work.
(Note that it's always legal to overflow live registers).
In this case, ensure to spill at least the stack pointer
of that frame. */
if (clone_flags & CLONE_VM) {
childregs->wmask = 1; /* can't share live windows */
/* check that caller window is live and same stack */
int len = childregs->wmask & ~0xf;
if (regs->areg[1] == usp && len != 0) {
int callinc = (regs->areg[0] >> 30) & 3;
int caller_ars = XCHAL_NUM_AREGS - callinc * 4;
put_user(regs->areg[caller_ars+1],
(unsigned __user*)(usp - 12));
}
childregs->wmask = 1;
childregs->windowstart = 1;
childregs->windowbase = 0;
} else {
int len = childregs->wmask & ~0xf;
memcpy(&childregs->areg[XCHAL_NUM_AREGS - len/4],
......@@ -230,11 +263,19 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
// FIXME: we need to set THREADPTR in thread_info...
if (clone_flags & CLONE_SETTLS)
childregs->areg[2] = childregs->areg[6];
} else {
/* In kernel space, we start a new thread with a new stack. */
childregs->wmask = 1;
childregs->areg[1] = tos;
p->thread.ra = MAKE_RA_FOR_CALL(
(unsigned long)ret_from_kernel_thread, 1);
/* pass parameters to ret_from_kernel_thread:
* a2 = thread_fn, a3 = thread_fn arg
*/
*((int *)childregs - 1) = thread_fn_arg;
*((int *)childregs - 2) = usp_thread_fn;
/* Childregs are only used when we're going to userspace
* in which case start_thread will set them up.
*/
}
#if (XTENSA_HAVE_COPROCESSORS || XTENSA_HAVE_IO_PORTS)
......@@ -330,32 +371,5 @@ long xtensa_clone(unsigned long clone_flags, unsigned long newsp,
void __user *child_tid, long a5,
struct pt_regs *regs)
{
if (!newsp)
newsp = regs->areg[1];
return do_fork(clone_flags, newsp, regs, 0, parent_tid, child_tid);
}
/*
* xtensa_execve() executes a new program.
*/
asmlinkage
long xtensa_execve(const char __user *name,
const char __user *const __user *argv,
const char __user *const __user *envp,
long a3, long a4, long a5,
struct pt_regs *regs)
{
long 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;
}
......@@ -32,10 +32,8 @@ typedef void (*syscall_t)(void);
syscall_t sys_call_table[__NR_syscall_count] /* FIXME __cacheline_aligned */= {
[0 ... __NR_syscall_count - 1] = (syscall_t)&sys_ni_syscall,
#undef __SYSCALL
#define __SYSCALL(nr,symbol,nargs) [ nr ] = (syscall_t)symbol,
#undef __KERNEL_SYSCALLS__
#include <asm/unistd.h>
#include <uapi/asm/unistd.h>
};
asmlinkage long xtensa_shmat(int shmid, char __user *shmaddr, int shmflg)
......@@ -49,7 +47,8 @@ asmlinkage long xtensa_shmat(int shmid, char __user *shmaddr, int shmflg)
return (long)ret;
}
asmlinkage long xtensa_fadvise64_64(int fd, int advice, unsigned long long offset, unsigned long long len)
asmlinkage long xtensa_fadvise64_64(int fd, int advice,
unsigned long long offset, unsigned long long len)
{
return sys_fadvise64_64(fd, offset, len, advice);
}
......
......@@ -43,7 +43,6 @@ EXPORT_SYMBOL(__strncpy_user);
EXPORT_SYMBOL(clear_page);
EXPORT_SYMBOL(copy_page);
EXPORT_SYMBOL(kernel_thread);
EXPORT_SYMBOL(empty_zero_page);
/*
......
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