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The include/linux/pgtable.h is going to be the home of generic page table manipulation functions. Start with moving asm-generic/pgtable.h to include/linux/pgtable.h and make the latter include asm/pgtable.h. Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Cain <bcain@codeaurora.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Zankel <chris@zankel.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Ungerer <gerg@linux-m68k.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Ley Foon Tan <ley.foon.tan@intel.com> Cc: Mark Salter <msalter@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Matt Turner <mattst88@gmail.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Nick Hu <nickhu@andestech.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vincent Chen <deanbo422@gmail.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Will Deacon <will@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: http://lkml.kernel.org/r/20200514170327.31389-3-rppt@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
46 lines
1.1 KiB
C
46 lines
1.1 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* Copyright (c) 2010-2011, The Linux Foundation. All rights reserved.
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*/
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/*
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* Support for user memory access from kernel. This will
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* probably be inlined for performance at some point, but
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* for ease of debug, and to a lesser degree for code size,
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* we implement here as subroutines.
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*/
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#include <linux/types.h>
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#include <linux/uaccess.h>
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#include <linux/pgtable.h>
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/*
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* For clear_user(), exploit previously defined copy_to_user function
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* and the fact that we've got a handy zero page defined in kernel/head.S
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*
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* dczero here would be even faster.
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*/
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__kernel_size_t __clear_user_hexagon(void __user *dest, unsigned long count)
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{
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long uncleared;
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while (count > PAGE_SIZE) {
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uncleared = raw_copy_to_user(dest, &empty_zero_page, PAGE_SIZE);
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if (uncleared)
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return count - (PAGE_SIZE - uncleared);
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count -= PAGE_SIZE;
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dest += PAGE_SIZE;
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}
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if (count)
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count = raw_copy_to_user(dest, &empty_zero_page, count);
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return count;
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}
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unsigned long clear_user_hexagon(void __user *dest, unsigned long count)
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{
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if (!access_ok(dest, count))
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return count;
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else
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return __clear_user_hexagon(dest, count);
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}
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