linux-stable/arch/x86/include/asm/page_64.h
Mike Rapoport (IBM) e5080a9677 mm, arch: add generic implementation of pfn_valid() for FLATMEM
Every architecture that supports FLATMEM memory model defines its own
version of pfn_valid() that essentially compares a pfn to max_mapnr.

Use mips/powerpc version implemented as static inline as a generic
implementation of pfn_valid() and drop its per-architecture definitions.

[rppt@kernel.org: fix the generic pfn_valid()]
  Link: https://lkml.kernel.org/r/Y9lg7R1Yd931C+y5@kernel.org
Link: https://lkml.kernel.org/r/20230129124235.209895-5-rppt@kernel.org
Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Guo Ren <guoren@kernel.org>		[csky]
Acked-by: Huacai Chen <chenhuacai@loongson.cn>	[LoongArch]
Acked-by: Stafford Horne <shorne@gmail.com>	[OpenRISC]
Acked-by: Michael Ellerman <mpe@ellerman.id.au>	[powerpc]
Reviewed-by: David Hildenbrand <david@redhat.com>
Tested-by: Conor Dooley <conor.dooley@microchip.com>
Cc: Brian Cain <bcain@quicinc.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-09 16:51:41 -08:00

102 lines
2.8 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_PAGE_64_H
#define _ASM_X86_PAGE_64_H
#include <asm/page_64_types.h>
#ifndef __ASSEMBLY__
#include <asm/cpufeatures.h>
#include <asm/alternative.h>
#include <linux/kmsan-checks.h>
/* duplicated to the one in bootmem.h */
extern unsigned long max_pfn;
extern unsigned long phys_base;
extern unsigned long page_offset_base;
extern unsigned long vmalloc_base;
extern unsigned long vmemmap_base;
static __always_inline unsigned long __phys_addr_nodebug(unsigned long x)
{
unsigned long y = x - __START_KERNEL_map;
/* use the carry flag to determine if x was < __START_KERNEL_map */
x = y + ((x > y) ? phys_base : (__START_KERNEL_map - PAGE_OFFSET));
return x;
}
#ifdef CONFIG_DEBUG_VIRTUAL
extern unsigned long __phys_addr(unsigned long);
extern unsigned long __phys_addr_symbol(unsigned long);
#else
#define __phys_addr(x) __phys_addr_nodebug(x)
#define __phys_addr_symbol(x) \
((unsigned long)(x) - __START_KERNEL_map + phys_base)
#endif
#define __phys_reloc_hide(x) (x)
void clear_page_orig(void *page);
void clear_page_rep(void *page);
void clear_page_erms(void *page);
static inline void clear_page(void *page)
{
/*
* Clean up KMSAN metadata for the page being cleared. The assembly call
* below clobbers @page, so we perform unpoisoning before it.
*/
kmsan_unpoison_memory(page, PAGE_SIZE);
alternative_call_2(clear_page_orig,
clear_page_rep, X86_FEATURE_REP_GOOD,
clear_page_erms, X86_FEATURE_ERMS,
"=D" (page),
"0" (page)
: "cc", "memory", "rax", "rcx");
}
void copy_page(void *to, void *from);
#ifdef CONFIG_X86_5LEVEL
/*
* User space process size. This is the first address outside the user range.
* There are a few constraints that determine this:
*
* On Intel CPUs, if a SYSCALL instruction is at the highest canonical
* address, then that syscall will enter the kernel with a
* non-canonical return address, and SYSRET will explode dangerously.
* We avoid this particular problem by preventing anything
* from being mapped at the maximum canonical address.
*
* On AMD CPUs in the Ryzen family, there's a nasty bug in which the
* CPUs malfunction if they execute code from the highest canonical page.
* They'll speculate right off the end of the canonical space, and
* bad things happen. This is worked around in the same way as the
* Intel problem.
*
* With page table isolation enabled, we map the LDT in ... [stay tuned]
*/
static __always_inline unsigned long task_size_max(void)
{
unsigned long ret;
alternative_io("movq %[small],%0","movq %[large],%0",
X86_FEATURE_LA57,
"=r" (ret),
[small] "i" ((1ul << 47)-PAGE_SIZE),
[large] "i" ((1ul << 56)-PAGE_SIZE));
return ret;
}
#endif /* CONFIG_X86_5LEVEL */
#endif /* !__ASSEMBLY__ */
#ifdef CONFIG_X86_VSYSCALL_EMULATION
# define __HAVE_ARCH_GATE_AREA 1
#endif
#endif /* _ASM_X86_PAGE_64_H */