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Merge branch 'arch-tile' into no-rebases

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This commit is contained in:
Al Viro 2012-11-16 22:27:38 -05:00
commit 94b237b6b9
17 changed files with 130 additions and 202 deletions
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2
arch/tile/Kconfig
View File

@ -21,6 +21,8 @@ config TILE
select ARCH_HAVE_NMI_SAFE_CMPXCHG
select GENERIC_CLOCKEVENTS
select MODULES_USE_ELF_RELA
select GENERIC_KERNEL_THREAD
select GENERIC_KERNEL_EXECVE
# FIXME: investigate whether we need/want these options.
# select HAVE_IOREMAP_PROT

15
arch/tile/include/asm/compat.h
View File

@ -275,18 +275,14 @@ extern int compat_setup_rt_frame(int sig, struct k_sigaction *ka,
struct compat_sigaction;
struct compat_siginfo;
struct compat_sigaltstack;
long compat_sys_execve(const char __user *path,
compat_uptr_t __user *argv,
compat_uptr_t __user *envp, struct pt_regs *);
long compat_sys_rt_sigaction(int sig, struct compat_sigaction __user *act,
struct compat_sigaction __user *oact,
size_t sigsetsize);
long compat_sys_rt_sigqueueinfo(int pid, int sig,
struct compat_siginfo __user *uinfo);
long compat_sys_rt_sigreturn(struct pt_regs *);
long compat_sys_rt_sigreturn(void);
long compat_sys_sigaltstack(const struct compat_sigaltstack __user *uss_ptr,
struct compat_sigaltstack __user *uoss_ptr,
struct pt_regs *);
struct compat_sigaltstack __user *uoss_ptr);
long compat_sys_truncate64(char __user *filename, u32 dummy, u32 low, u32 high);
long compat_sys_ftruncate64(unsigned int fd, u32 dummy, u32 low, u32 high);
long compat_sys_pread64(unsigned int fd, char __user *ubuf, size_t count,
@ -303,12 +299,7 @@ long compat_sys_fallocate(int fd, int mode,
long compat_sys_sched_rr_get_interval(compat_pid_t pid,
struct compat_timespec __user *interval);
/* These are the intvec_64.S trampolines. */
long _compat_sys_execve(const char __user *path,
const compat_uptr_t __user *argv,
const compat_uptr_t __user *envp);
long _compat_sys_sigaltstack(const struct compat_sigaltstack __user *uss_ptr,
struct compat_sigaltstack __user *uoss_ptr);
/* Assembly trampoline to avoid clobbering r0. */
long _compat_sys_rt_sigreturn(void);
#endif /* _ASM_TILE_COMPAT_H */

1
arch/tile/include/asm/elf.h
View File

@ -148,6 +148,7 @@ extern int arch_setup_additional_pages(struct linux_binprm *bprm,
#define compat_start_thread(regs, ip, usp) do { \
regs->pc = ptr_to_compat_reg((void *)(ip)); \
regs->sp = ptr_to_compat_reg((void *)(usp)); \
single_step_execve(); \
} while (0)
/*

4
arch/tile/include/asm/processor.h
View File

@ -211,6 +211,7 @@ static inline void start_thread(struct pt_regs *regs,
{
regs->pc = pc;
regs->sp = usp;
single_step_execve();
}
/* Free all resources held by a thread. */
@ -239,6 +240,9 @@ unsigned long get_wchan(struct task_struct *p);
#define KSTK_TOP(task) (task_ksp0(task) - STACK_TOP_DELTA)
#define task_pt_regs(task) \
((struct pt_regs *)(task_ksp0(task) - KSTK_PTREGS_GAP) - 1)
#define current_pt_regs() \
((struct pt_regs *)((stack_pointer | (THREAD_SIZE - 1)) - \
(KSTK_PTREGS_GAP - 1)) - 1)
#define task_sp(task) (task_pt_regs(task)->sp)
#define task_pc(task) (task_pt_regs(task)->pc)
/* Aliases for pc and sp (used in fs/proc/array.c) */

5
arch/tile/include/asm/switch_to.h
View File

@ -68,7 +68,10 @@ extern unsigned long get_switch_to_pc(void);
/* Support function for forking a new task. */
void ret_from_fork(void);
/* Called from ret_from_fork() when a new process starts up. */
/* Support function for forking a new kernel thread. */
void ret_from_kernel_thread(void *fn, void *arg);
/* Called from ret_from_xxx() when a new process starts up. */
struct task_struct *sim_notify_fork(struct task_struct *prev);
#endif /* !__ASSEMBLY__ */

20
arch/tile/include/asm/syscalls.h
View File

@ -51,8 +51,7 @@ long sys_cacheflush(unsigned long addr, unsigned long len,
#ifndef __tilegx__
/* mm/fault.c */
long sys_cmpxchg_badaddr(unsigned long address, struct pt_regs *);
long _sys_cmpxchg_badaddr(unsigned long address);
long sys_cmpxchg_badaddr(unsigned long address);
#endif
#ifdef CONFIG_COMPAT
@ -63,14 +62,23 @@ long sys_truncate64(const char __user *path, loff_t length);
long sys_ftruncate64(unsigned int fd, loff_t length);
#endif
/* Provide versions of standard syscalls that use current_pt_regs(). */
long sys_clone(unsigned long clone_flags, unsigned long newsp,
void __user *parent_tid, void __user *child_tid);
long sys_execve(const char __user *filename,
const char __user *const __user *argv,
const char __user *const __user *envp);
long sys_rt_sigreturn(void);
long sys_sigaltstack(const stack_t __user *, stack_t __user *);
#define sys_clone sys_clone
#define sys_execve sys_execve
#define sys_rt_sigreturn sys_rt_sigreturn
#define sys_sigaltstack sys_sigaltstack
/* These are the intvec*.S trampolines. */
long _sys_sigaltstack(const stack_t __user *, stack_t __user *);
long _sys_rt_sigreturn(void);
long _sys_clone(unsigned long clone_flags, unsigned long newsp,
void __user *parent_tid, void __user *child_tid);
long _sys_execve(const char __user *filename,
const char __user *const __user *argv,
const char __user *const __user *envp);
#include <asm-generic/syscalls.h>

1
arch/tile/include/asm/unistd.h
View File

@ -16,4 +16,5 @@
#define __ARCH_WANT_SYS_LLSEEK
#endif
#define __ARCH_WANT_SYS_NEWFSTATAT
#define __ARCH_WANT_SYS_EXECVE
#include <uapi/asm/unistd.h>

5
arch/tile/kernel/compat.c
View File

@ -102,10 +102,9 @@ long compat_sys_sched_rr_get_interval(compat_pid_t pid,
#define compat_sys_fadvise64_64 sys32_fadvise64_64
#define compat_sys_readahead sys32_readahead
/* Call the trampolines to manage pt_regs where necessary. */
#define compat_sys_execve _compat_sys_execve
#define compat_sys_sigaltstack _compat_sys_sigaltstack
/* Call the assembly trampolines where necessary. */
#define compat_sys_rt_sigreturn _compat_sys_rt_sigreturn
#undef sys_clone
#define sys_clone _sys_clone
/*

10
arch/tile/kernel/compat_signal.c
View File

@ -197,8 +197,7 @@ int copy_siginfo_from_user32(siginfo_t *to, struct compat_siginfo __user *from)
}
long compat_sys_sigaltstack(const struct compat_sigaltstack __user *uss_ptr,
struct compat_sigaltstack __user *uoss_ptr,
struct pt_regs *regs)
struct compat_sigaltstack __user *uoss_ptr)
{
stack_t uss, uoss;
int ret;
@ -219,7 +218,7 @@ long compat_sys_sigaltstack(const struct compat_sigaltstack __user *uss_ptr,
set_fs(KERNEL_DS);
ret = do_sigaltstack(uss_ptr ? (stack_t __user __force *)&uss : NULL,
(stack_t __user __force *)&uoss,
(unsigned long)compat_ptr(regs->sp));
(unsigned long)compat_ptr(current_pt_regs()->sp));
set_fs(seg);
if (ret >= 0 && uoss_ptr) {
if (!access_ok(VERIFY_WRITE, uoss_ptr, sizeof(*uoss_ptr)) ||
@ -232,8 +231,9 @@ long compat_sys_sigaltstack(const struct compat_sigaltstack __user *uss_ptr,
}
/* The assembly shim for this function arranges to ignore the return value. */
long compat_sys_rt_sigreturn(struct pt_regs *regs)
long compat_sys_rt_sigreturn(void)
{
struct pt_regs *regs = current_pt_regs();
struct compat_rt_sigframe __user *frame =
(struct compat_rt_sigframe __user *) compat_ptr(regs->sp);
sigset_t set;
@ -248,7 +248,7 @@ long compat_sys_rt_sigreturn(struct pt_regs *regs)
if (restore_sigcontext(regs, &frame->uc.uc_mcontext))
goto badframe;
if (compat_sys_sigaltstack(&frame->uc.uc_stack, NULL, regs) != 0)
if (compat_sys_sigaltstack(&frame->uc.uc_stack, NULL) != 0)
goto badframe;
return 0;

11
arch/tile/kernel/entry.S
View File

@ -27,17 +27,6 @@ STD_ENTRY(current_text_addr)
{ move r0, lr; jrp lr }
STD_ENDPROC(current_text_addr)
/*
* Implement execve(). The i386 code has a note that forking from kernel
* space results in no copy on write until the execve, so we should be
* careful not to write to the stack here.
*/
STD_ENTRY(kernel_execve)
moveli TREG_SYSCALL_NR_NAME, __NR_execve
swint1
jrp lr
STD_ENDPROC(kernel_execve)
/*
* We don't run this function directly, but instead copy it to a page
* we map into every user process. See vdso_setup().

29
arch/tile/kernel/intvec_32.S
View File

@ -1291,6 +1291,21 @@ STD_ENTRY(ret_from_fork)
}
STD_ENDPROC(ret_from_fork)
STD_ENTRY(ret_from_kernel_thread)
jal sim_notify_fork
jal schedule_tail
FEEDBACK_REENTER(ret_from_fork)
{
move r0, r31
jalr r30
}
FEEDBACK_REENTER(ret_from_kernel_thread)
{
movei r30, 0 /* not an NMI */
j .Lresume_userspace /* jump into middle of interrupt_return */
}
STD_ENDPROC(ret_from_kernel_thread)
/*
* Code for ill interrupt.
*/
@ -1437,15 +1452,6 @@ STD_ENTRY_LOCAL(bad_intr)
panic "Unhandled interrupt %#x: PC %#lx"
STD_ENDPROC(bad_intr)
/* Put address of pt_regs in reg and jump. */
#define PTREGS_SYSCALL(x, reg) \
STD_ENTRY(_##x); \
{ \
PTREGS_PTR(reg, PTREGS_OFFSET_BASE); \
j x \
}; \
STD_ENDPROC(_##x)
/*
* Special-case sigreturn to not write r0 to the stack on return.
* This is technically more efficient, but it also avoids difficulties
@ -1461,12 +1467,9 @@ STD_ENTRY_LOCAL(bad_intr)
}; \
STD_ENDPROC(_##x)
PTREGS_SYSCALL(sys_execve, r3)
PTREGS_SYSCALL(sys_sigaltstack, r2)
PTREGS_SYSCALL_SIGRETURN(sys_rt_sigreturn, r0)
PTREGS_SYSCALL(sys_cmpxchg_badaddr, r1)
/* Save additional callee-saves to pt_regs, put address in r4 and jump. */
/* Save additional callee-saves to pt_regs and jump to standard function. */
STD_ENTRY(_sys_clone)
push_extra_callee_saves r4
j sys_clone

30
arch/tile/kernel/intvec_64.S
View File

@ -1150,6 +1150,21 @@ STD_ENTRY(ret_from_fork)
}
STD_ENDPROC(ret_from_fork)
STD_ENTRY(ret_from_kernel_thread)
jal sim_notify_fork
jal schedule_tail
FEEDBACK_REENTER(ret_from_fork)
{
move r0, r31
jalr r30
}
FEEDBACK_REENTER(ret_from_kernel_thread)
{
movei r30, 0 /* not an NMI */
j .Lresume_userspace /* jump into middle of interrupt_return */
}
STD_ENDPROC(ret_from_kernel_thread)
/* Various stub interrupt handlers and syscall handlers */
STD_ENTRY_LOCAL(_kernel_double_fault)
@ -1166,15 +1181,6 @@ STD_ENTRY_LOCAL(bad_intr)
panic "Unhandled interrupt %#x: PC %#lx"
STD_ENDPROC(bad_intr)
/* Put address of pt_regs in reg and jump. */
#define PTREGS_SYSCALL(x, reg) \
STD_ENTRY(_##x); \
{ \
PTREGS_PTR(reg, PTREGS_OFFSET_BASE); \
j x \
}; \
STD_ENDPROC(_##x)
/*
* Special-case sigreturn to not write r0 to the stack on return.
* This is technically more efficient, but it also avoids difficulties
@ -1190,16 +1196,12 @@ STD_ENTRY_LOCAL(bad_intr)
}; \
STD_ENDPROC(_##x)
PTREGS_SYSCALL(sys_execve, r3)
PTREGS_SYSCALL(sys_sigaltstack, r2)
PTREGS_SYSCALL_SIGRETURN(sys_rt_sigreturn, r0)
#ifdef CONFIG_COMPAT
PTREGS_SYSCALL(compat_sys_execve, r3)
PTREGS_SYSCALL(compat_sys_sigaltstack, r2)
PTREGS_SYSCALL_SIGRETURN(compat_sys_rt_sigreturn, r0)
#endif
/* Save additional callee-saves to pt_regs, put address in r4 and jump. */
/* Save additional callee-saves to pt_regs and jump to standard function. */
STD_ENTRY(_sys_clone)
push_extra_callee_saves r4
j sys_clone

174
arch/tile/kernel/process.c
View File

@ -157,18 +157,50 @@ void arch_release_thread_info(struct thread_info *info)
static void save_arch_state(struct thread_struct *t);
int copy_thread(unsigned long clone_flags, unsigned long sp,
unsigned long stack_size,
struct task_struct *p, struct pt_regs *regs)
unsigned long arg,
struct task_struct *p, struct pt_regs *unused)
{
struct pt_regs *childregs;
struct pt_regs *childregs = task_pt_regs(p);
unsigned long ksp;
unsigned long *callee_regs;
/*
* When creating a new kernel thread we pass sp as zero.
* Assign it to a reasonable value now that we have the stack.
* Set up the stack and stack pointer appropriately for the
* new child to find itself woken up in __switch_to().
* The callee-saved registers must be on the stack to be read;
* the new task will then jump to assembly support to handle
* calling schedule_tail(), etc., and (for userspace tasks)
* returning to the context set up in the pt_regs.
*/
if (sp == 0 && regs->ex1 == PL_ICS_EX1(KERNEL_PL, 0))
sp = KSTK_TOP(p);
ksp = (unsigned long) childregs;
ksp -= C_ABI_SAVE_AREA_SIZE; /* interrupt-entry save area */
((long *)ksp)[0] = ((long *)ksp)[1] = 0;
ksp -= CALLEE_SAVED_REGS_COUNT * sizeof(unsigned long);
callee_regs = (unsigned long *)ksp;
ksp -= C_ABI_SAVE_AREA_SIZE; /* __switch_to() save area */
((long *)ksp)[0] = ((long *)ksp)[1] = 0;
p->thread.ksp = ksp;
/* Record the pid of the task that created this one. */
p->thread.creator_pid = current->pid;
if (unlikely(p->flags & PF_KTHREAD)) {
/* kernel thread */
memset(childregs, 0, sizeof(struct pt_regs));
memset(&callee_regs[2], 0,
(CALLEE_SAVED_REGS_COUNT - 2) * sizeof(unsigned long));
callee_regs[0] = sp; /* r30 = function */
callee_regs[1] = arg; /* r31 = arg */
childregs->ex1 = PL_ICS_EX1(KERNEL_PL, 0);
p->thread.pc = (unsigned long) ret_from_kernel_thread;
return 0;
}
/*
* Start new thread in ret_from_fork so it schedules properly
* and then return from interrupt like the parent.
*/
p->thread.pc = (unsigned long) ret_from_fork;
/*
* Do not clone step state from the parent; each thread
@ -176,52 +208,27 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
*/
task_thread_info(p)->step_state = NULL;
/*
* Start new thread in ret_from_fork so it schedules properly
* and then return from interrupt like the parent.
*/
p->thread.pc = (unsigned long) ret_from_fork;
/* Save user stack top pointer so we can ID the stack vm area later. */
p->thread.usp0 = sp;
/* Record the pid of the process that created this one. */
p->thread.creator_pid = current->pid;
/*
* Copy the registers onto the kernel stack so the
* return-from-interrupt code will reload it into registers.
*/
childregs = task_pt_regs(p);
*childregs = *regs;
*childregs = *current_pt_regs();
childregs->regs[0] = 0; /* return value is zero */
childregs->sp = sp; /* override with new user stack pointer */
if (sp)
childregs->sp = sp; /* override with new user stack pointer */
memcpy(callee_regs, &childregs->regs[CALLEE_SAVED_FIRST_REG],
CALLEE_SAVED_REGS_COUNT * sizeof(unsigned long));
/* Save user stack top pointer so we can ID the stack vm area later. */
p->thread.usp0 = childregs->sp;
/*
* If CLONE_SETTLS is set, set "tp" in the new task to "r4",
* which is passed in as arg #5 to sys_clone().
*/
if (clone_flags & CLONE_SETTLS)
childregs->tp = regs->regs[4];
childregs->tp = childregs->regs[4];
/*
* Copy the callee-saved registers from the passed pt_regs struct
* into the context-switch callee-saved registers area.
* This way when we start the interrupt-return sequence, the
* callee-save registers will be correctly in registers, which
* is how we assume the compiler leaves them as we start doing
* the normal return-from-interrupt path after calling C code.
* Zero out the C ABI save area to mark the top of the stack.
*/
ksp = (unsigned long) childregs;
ksp -= C_ABI_SAVE_AREA_SIZE; /* interrupt-entry save area */
((long *)ksp)[0] = ((long *)ksp)[1] = 0;
ksp -= CALLEE_SAVED_REGS_COUNT * sizeof(unsigned long);
memcpy((void *)ksp, &regs->regs[CALLEE_SAVED_FIRST_REG],
CALLEE_SAVED_REGS_COUNT * sizeof(unsigned long));
ksp -= C_ABI_SAVE_AREA_SIZE; /* __switch_to() save area */
((long *)ksp)[0] = ((long *)ksp)[1] = 0;
p->thread.ksp = ksp;
#if CHIP_HAS_TILE_DMA()
/*
@ -578,61 +585,13 @@ int do_work_pending(struct pt_regs *regs, u32 thread_info_flags)
}
/* Note there is an implicit fifth argument if (clone_flags & CLONE_SETTLS). */
SYSCALL_DEFINE5(clone, unsigned long, clone_flags, unsigned long, newsp,
void __user *, parent_tidptr, void __user *, child_tidptr,
struct pt_regs *, regs)
SYSCALL_DEFINE4(clone, unsigned long, clone_flags, unsigned long, newsp,
void __user *, parent_tidptr, void __user *, child_tidptr)
{
if (!newsp)
newsp = regs->sp;
return do_fork(clone_flags, newsp, regs, 0,
return do_fork(clone_flags, newsp, current_pt_regs(), 0,
parent_tidptr, child_tidptr);
}
/*
* sys_execve() executes a new program.
*/
SYSCALL_DEFINE4(execve, const char __user *, path,
const char __user *const __user *, argv,
const char __user *const __user *, envp,
struct pt_regs *, regs)
{
long error;
struct filename *filename;
filename = getname(path);
error = PTR_ERR(filename);
if (IS_ERR(filename))
goto out;
error = do_execve(filename->name, argv, envp, regs);
putname(filename);
if (error == 0)
single_step_execve();
out:
return error;
}
#ifdef CONFIG_COMPAT
long compat_sys_execve(const char __user *path,
compat_uptr_t __user *argv,
compat_uptr_t __user *envp,
struct pt_regs *regs)
{
long error;
struct filename *filename;
filename = getname(path);
error = PTR_ERR(filename);
if (IS_ERR(filename))
goto out;
error = compat_do_execve(filename->name, argv, envp, regs);
putname(filename);
if (error == 0)
single_step_execve();
out:
return error;
}
#endif
unsigned long get_wchan(struct task_struct *p)
{
struct KBacktraceIterator kbt;
@ -650,37 +609,6 @@ unsigned long get_wchan(struct task_struct *p)
return 0;
}
/*
* We pass in lr as zero (cleared in kernel_thread) and the caller
* part of the backtrace ABI on the stack also zeroed (in copy_thread)
* so that backtraces will stop with this function.
* Note that we don't use r0, since copy_thread() clears it.
*/
static void start_kernel_thread(int dummy, int (*fn)(int), int 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.ex1 = PL_ICS_EX1(KERNEL_PL, 0); /* run at kernel PL, no ICS */
regs.pc = (long) start_kernel_thread;
regs.flags = PT_FLAGS_CALLER_SAVES; /* need to restore r1 and r2 */
regs.regs[1] = (long) fn; /* function pointer */
regs.regs[2] = (long) arg; /* parameter register */
/* Ok, create the new process.. */
return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, &regs,
0, NULL, NULL);
}
EXPORT_SYMBOL(kernel_thread);
/* Flush thread state. */
void flush_thread(void)
{

9
arch/tile/kernel/signal.c
View File

@ -37,10 +37,10 @@
#define DEBUG_SIG 0
SYSCALL_DEFINE3(sigaltstack, const stack_t __user *, uss,
stack_t __user *, uoss, struct pt_regs *, regs)
SYSCALL_DEFINE2(sigaltstack, const stack_t __user *, uss,
stack_t __user *, uoss)
{
return do_sigaltstack(uss, uoss, regs->sp);
return do_sigaltstack(uss, uoss, current_pt_regs()->sp);
}
@ -83,8 +83,9 @@ void signal_fault(const char *type, struct pt_regs *regs,
}
/* The assembly shim for this function arranges to ignore the return value. */
SYSCALL_DEFINE1(rt_sigreturn, struct pt_regs *, regs)
SYSCALL_DEFINE0(rt_sigreturn)
{
struct pt_regs *regs = current_pt_regs();
struct rt_sigframe __user *frame =
(struct rt_sigframe __user *)(regs->sp);
sigset_t set;

9
arch/tile/kernel/sys.c
View File

@ -106,14 +106,11 @@ SYSCALL_DEFINE6(mmap, unsigned long, addr, unsigned long, len,
#define sys_readahead sys32_readahead
#endif
/* Call the trampolines to manage pt_regs where necessary. */
#define sys_execve _sys_execve
#define sys_sigaltstack _sys_sigaltstack
/* Call the assembly trampolines where necessary. */
#undef sys_rt_sigreturn
#define sys_rt_sigreturn _sys_rt_sigreturn
#undef sys_clone
#define sys_clone _sys_clone
#ifndef __tilegx__
#define sys_cmpxchg_badaddr _sys_cmpxchg_badaddr
#endif
/*
* Note that we can't include <linux/unistd.h> here since the header

5
arch/tile/mm/fault.c
View File

@ -70,9 +70,10 @@ static noinline void force_sig_info_fault(const char *type, int si_signo,
* Synthesize the fault a PL0 process would get by doing a word-load of
* an unaligned address or a high kernel address.
*/
SYSCALL_DEFINE2(cmpxchg_badaddr, unsigned long, address,
struct pt_regs *, regs)
SYSCALL_DEFINE1(cmpxchg_badaddr, unsigned long, address)
{
struct pt_regs *regs = current_pt_regs();
if (address >= PAGE_OFFSET)
force_sig_info_fault("atomic segfault", SIGSEGV, SEGV_MAPERR,
address, INT_DTLB_MISS, current, regs);

2
include/linux/compat.h
View File

@ -286,10 +286,8 @@ asmlinkage ssize_t compat_sys_pwritev(unsigned long fd,
int compat_do_execve(const char *filename, const compat_uptr_t __user *argv,
const compat_uptr_t __user *envp, struct pt_regs *regs);
#ifdef __ARCH_WANT_SYS_EXECVE
asmlinkage long compat_sys_execve(const char __user *filename, const compat_uptr_t __user *argv,
const compat_uptr_t __user *envp);
#endif
asmlinkage long compat_sys_select(int n, compat_ulong_t __user *inp,
compat_ulong_t __user *outp, compat_ulong_t __user *exp,