linux/include/asm-generic/5level-fixup.h
Dan Williams 0a9fe8ca84 x86/mm: Validate kernel_physical_mapping_init() PTE population
The usage of __flush_tlb_all() in the kernel_physical_mapping_init()
path is not necessary. In general flushing the TLB is not required when
updating an entry from the !present state. However, to give confidence
in the future removal of TLB flushing in this path, use the new
set_pte_safe() family of helpers to assert that the !present assumption
is true in this path.

[ mingo: Minor readability edits. ]

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Suggested-by: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/154395944177.32119.8524957429632012270.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-12-05 09:03:06 +01:00

45 lines
1.2 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _5LEVEL_FIXUP_H
#define _5LEVEL_FIXUP_H
#define __ARCH_HAS_5LEVEL_HACK
#define __PAGETABLE_P4D_FOLDED 1
#define P4D_SHIFT PGDIR_SHIFT
#define P4D_SIZE PGDIR_SIZE
#define P4D_MASK PGDIR_MASK
#define MAX_PTRS_PER_P4D 1
#define PTRS_PER_P4D 1
#define p4d_t pgd_t
#define pud_alloc(mm, p4d, address) \
((unlikely(pgd_none(*(p4d))) && __pud_alloc(mm, p4d, address)) ? \
NULL : pud_offset(p4d, address))
#define p4d_alloc(mm, pgd, address) (pgd)
#define p4d_offset(pgd, start) (pgd)
#define p4d_none(p4d) 0
#define p4d_bad(p4d) 0
#define p4d_present(p4d) 1
#define p4d_ERROR(p4d) do { } while (0)
#define p4d_clear(p4d) pgd_clear(p4d)
#define p4d_val(p4d) pgd_val(p4d)
#define p4d_populate(mm, p4d, pud) pgd_populate(mm, p4d, pud)
#define p4d_populate_safe(mm, p4d, pud) pgd_populate(mm, p4d, pud)
#define p4d_page(p4d) pgd_page(p4d)
#define p4d_page_vaddr(p4d) pgd_page_vaddr(p4d)
#define __p4d(x) __pgd(x)
#define set_p4d(p4dp, p4d) set_pgd(p4dp, p4d)
#undef p4d_free_tlb
#define p4d_free_tlb(tlb, x, addr) do { } while (0)
#define p4d_free(mm, x) do { } while (0)
#define __p4d_free_tlb(tlb, x, addr) do { } while (0)
#undef p4d_addr_end
#define p4d_addr_end(addr, end) (end)
#endif