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https://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson
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e28cbf2293
On an architecture that supports 32-bit compat we need to override the reported machine in uname with the 32-bit value. Instead of doing this separately in every architecture introduce a COMPAT_UTS_MACHINE define in <asm/compat.h> and apply it directly in sys_newuname(). Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Jeff Dike <jdike@addtoit.com> Cc: Hirokazu Takata <takata@linux-m32r.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: James Morris <jmorris@namei.org> Cc: Andreas Schwab <schwab@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
103 lines
2.6 KiB
C
103 lines
2.6 KiB
C
/*
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* Copyright (C) 2003 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
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* Copyright 2003 PathScale, Inc.
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*
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* Licensed under the GPL
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*/
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#include "linux/linkage.h"
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#include "linux/personality.h"
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#include "linux/utsname.h"
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#include "asm/prctl.h" /* XXX This should get the constants from libc */
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#include "asm/uaccess.h"
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#include "os.h"
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long arch_prctl(struct task_struct *task, int code, unsigned long __user *addr)
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{
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unsigned long *ptr = addr, tmp;
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long ret;
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int pid = task->mm->context.id.u.pid;
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/*
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* With ARCH_SET_FS (and ARCH_SET_GS is treated similarly to
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* be safe), we need to call arch_prctl on the host because
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* setting %fs may result in something else happening (like a
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* GDT or thread.fs being set instead). So, we let the host
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* fiddle the registers and thread struct and restore the
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* registers afterwards.
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*
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* So, the saved registers are stored to the process (this
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* needed because a stub may have been the last thing to run),
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* arch_prctl is run on the host, then the registers are read
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* back.
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*/
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switch (code) {
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case ARCH_SET_FS:
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case ARCH_SET_GS:
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ret = restore_registers(pid, ¤t->thread.regs.regs);
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if (ret)
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return ret;
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break;
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case ARCH_GET_FS:
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case ARCH_GET_GS:
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/*
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* With these two, we read to a local pointer and
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* put_user it to the userspace pointer that we were
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* given. If addr isn't valid (because it hasn't been
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* faulted in or is just bogus), we want put_user to
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* fault it in (or return -EFAULT) instead of having
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* the host return -EFAULT.
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*/
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ptr = &tmp;
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}
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ret = os_arch_prctl(pid, code, ptr);
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if (ret)
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return ret;
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switch (code) {
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case ARCH_SET_FS:
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current->thread.arch.fs = (unsigned long) ptr;
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ret = save_registers(pid, ¤t->thread.regs.regs);
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break;
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case ARCH_SET_GS:
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ret = save_registers(pid, ¤t->thread.regs.regs);
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break;
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case ARCH_GET_FS:
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ret = put_user(tmp, addr);
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break;
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case ARCH_GET_GS:
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ret = put_user(tmp, addr);
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break;
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}
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return ret;
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}
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long sys_arch_prctl(int code, unsigned long addr)
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{
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return arch_prctl(current, code, (unsigned long __user *) addr);
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}
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long sys_clone(unsigned long clone_flags, unsigned long newsp,
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void __user *parent_tid, void __user *child_tid)
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{
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long ret;
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if (!newsp)
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newsp = UPT_SP(¤t->thread.regs.regs);
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current->thread.forking = 1;
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ret = do_fork(clone_flags, newsp, ¤t->thread.regs, 0, parent_tid,
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child_tid);
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current->thread.forking = 0;
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return ret;
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}
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void arch_switch_to(struct task_struct *to)
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{
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if ((to->thread.arch.fs == 0) || (to->mm == NULL))
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return;
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arch_prctl(to, ARCH_SET_FS, (void __user *) to->thread.arch.fs);
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}
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